WO2001077575A1

WO2001077575A1 - Portable illumination device

Info

Publication number: WO2001077575A1
Application number: PCT/US2001/011168
Authority: WO
Inventors: David M. Allen
Original assignee: Allen David M
Priority date: 2000-04-05
Filing date: 2001-04-04
Publication date: 2001-10-18
Also published as: AU2001253190A1

Abstract

A portable illumination device (10) includes a miniature, unitary housing (12) adapted to enclose a flashlight lamp (16) having electrical contacts or leads (32, 34) in switchable connection to a discoid battery (14). The housing (12) is formed of impact-resistant material and defines a battery compartment (18) and lamp socket (20) integrally formed within the housing (12). The battery compartment is dimensioned to receive at least one discoid battery (14), and the lamp socket (20) is positioned within the housing (12) forward of the battery compartment and dimensioned to receive a contact- or lead-bearing end (24) of the flashlight lamp (16). Electrical connections and a switching device electrically interconnects the battery (14) and lamp (16) to modulate power delivery to the lamp (16). A water resistant battery cap (64) and seating collar (100) for the lamp may optionally be included in the design. A microprocessor may be added or substituted for the switch to control one or more modes of operation of the device (10).

Description

PORTABLE ILLUMINATION DEVICE

BACKGROUND OF THE INVENTION

The instant invention relates generally to portable illumination devices. More specifically, the invention relates to miniature, hand-held flashlight devices for personal convenience, entertainment, security and professional use.

Hand-held illumination devices, such as portable lanterns and flashlights, have long been in use for a variety of purposes and come in numerous different designs. The most common portable lighting device is the conventional flashlight. The typical flashlight design incorporates a cylindrical battery housing adapted to hold one or more standard dry cell batteries. Coupled to one end of the battery housing is a lamp assembly. The lamp is ordinarily secured in a separate housing threadedly connected with the battery housing. The lamp is generally positioned so that one electrical contact or lead of the lamp is held in electrical connection with one terminal of the battery. A switch, most often located on the battery housing, regulates operation of the lamp by electrically connecting or disconnecting a second battery terminal to a second contact or lead of the lamp. Alternative switch designs move the lamp into electrical connection with a lead extending from the second battery terminal, for example by threading the lamp housing more tightly onto the battery housing to advance the lamp closer to the lead. The lamp housing generally includes a conical, mirrored reflector to focus light from the lamp in a narrow output beam, as well as a clear lamp cover to shield the lamp from impact and moisture.

Additional hand-held illumination devices have been developed with the goal of achieving a miniaturized construction, to offer improved convenience of storage and transport and thereby facilitate a larger range of uses. Thus, a variety of more recent flashlight designs have been developed or proposed that incorporate components having a reduced size compared to conventional flashlight components, including smaller batteries and battery housings, lamps and lamp housings, and switching and electrical connecting components. Portable lights of this "miniaturized" type have been developed or proposed for a variety of uses. These uses largely overlap with conventional flashlight uses, for example, to provide emergency illumination in the event of power failures, automobile breakdowns, etc., security and convenience illumination for home, auto, and outdoor use, and professional uses incidental to such occupations as fire safety and rescue, marine transportation and commerce, home and commercial security, and military and police work.

Existing miniature flashlight devices, commonly referred to as "pocket" and "keychain" flashlights, have been employed for these and additional uses, and are found in two principal design configurations. One principal design is a "pen-light" design incorporating the same general structural features as conventional flashlights. Thus, a variety of pocket-sized flashlights are available that include a small, cylindrical battery housing to enclose one or more small, cylindrical dry-cell batteries (typically AA- or AAA-cells). These designs also feature a miniature lamp housing with reflector and a conventional on/off switching mechanism. The switch may be a simple, thumb-actuated switch located on the battery housing or may be operated by repositioning (e.g., rotating or telescoping) the lamp housing relative to the battery housing.

A second principal design for keychain flashlights incorporates a modified flashlight body adapted to hold disc- or coin-shaped batteries, such as are commonly used to power watches, hearing aids and other miniature portable electronic devices. These miniature flashlights generally have a flattened body as disclosed in U.S. Design Patent No. 375,372, issued November 5, 1996 to Allen; U.S. Design Patent No. 321,785, issued November 26, 1991 to Garrity; U.S. Design Patent No. 380,566, issued July 1, 1997 to Chen, which may be constructed to serve as both a battery enclosure and lamp housing (see, e.g., U.S. Patent No. 5,386,351, issued January 31, 1995 to Tabor). Among these designs, Tabor, U.S. Patent No. 5,386,351, discloses a miniature convenience flashlight having a flattened, elongate body construction and a lamp and switch design specifically adapted for use with a single, discoid battery. The body is of a two-part, polymeric construction with a case portion adapted to seat the battery and receive and retain elongate leads for electrically connecting the lamp and battery. A front end of the case portion has three lead-retaining, parallel spaced ribs, while the back end of the case has two parallel battery-locating ribs, all projecting inwardly. The body also includes a cover portion that mates with the case portion and snaps together therewith to enclose the battery and lamp in a sandwich-type mounting configuration. The lamp, which is sandwiched between front-end portions of the elongate case and cover, is surrounded by an integral hood portion of the cover which is oriented to direct illumination normal to the cover to facilitate use of the flashlight when it is mounted on a hand-held remote control device. The lamp is connected to the battery by elongate leads that extend through the retaining ribs at the front end of the case toward the rear where the battery is located. The leads diverge rearwardly toward opposing, upper and lower positions adjacent the opposing terminals of the battery.

Switching of the Tabor flashlight device is achieved by a simple, on/off push-button switch which incorporates a separate, push-button element adapted to fit within an aperture in the case portion of the body and to seat upon an annular recess in the case surrounding the aperture. The button has legs that function like springs to keep the button positioned outwardly away from the lower battery terminal and the lower lamp lead which is juxtaposed between the button and lower battery terminal. When the button is depressed, the legs flex and allow the button to advance the lower lamp lead into contact with the lower battery terminal, thereby closing a circuit to switch the lamp on. Release of the push-button automatically move reopens the circuit and shuts the lamp off. Prior designs for miniature flashlights, including the Tabor design briefly described above, suffer from a number of drawbacks and/or fail to provide a range of desired features that are contemplated within the instant invention. For example, certain existing miniature flashlight designs feature an excessive number of parts, or they otherwise impose undue materials and labor costs for manufacturing and assembly. Likewise, many existing mini-flashlight designs are excessively vulnerable to wear or breakage, or fail to provide sufficient protection against moisture and other adverse environmental conditions. Yet additional drawbacks of previous mini-flashlight designs include substantial difficulties for disassembly to replace batteries, as well as costly and/or unreliable switching systems having a limited range of switching functions.

SUMMARY OF THE INVENTION It is therefore an object of the instant invention to provide a portable illumination device that provides for improved storage, transport, and handling over conventional flashlights and previously described miniaturized flashlights.

It is a further object of the invention to provide a miniature flashlight having a flattened body construction adapted for improved housing and securing of discoid batteries and miniaturized lamps, such as a monochromatic or polychromatic light emitting diode (LED) lamp, and which is produced with minimal attendant manufacturing and assembly costs.

It is a related object of the invention to satisfy the above objects in a miniature flashlight having a housing specially adapted for moisture and dust resistance, particularly to shield battery and electrical connector components of the flashlight from adverse environmental conditions. Similarly, it is a related object of the invention to provide a miniature flashlight that provides for fast and simple battery replacement with minimal attendant manufacturing and assembly costs.

It is another object of the invention to satisfy the above objects in a miniature flashlight that incorporates specially-constructed housing, lamp and electrical components mutually designed to optimize the functional range and reliability of the lighting device.

It is yet another object of the invention to fulfill the above objects in a miniature flashlight that incorporates novel housing and switching features to increase the range of operation modes and uses for the flashlight with minimal attendant manufacturing and assembly costs.

The invention fulfills these objects and satisfies additional objects and advantages that will become apparent from the description and drawings below.

The instant invention provides a novel, miniature flashlight featuring a compact, unitary housing adapted to enclose a battery and miniaturized lamp. Enclosed within or integrated with the housing are electrical connector elements (posts, wires, leads) that electrically connect the contacts or leads of the lamp to battery terminals of opposite polarity to complete an electrical circuit supplying power from the battery to the lamp. Also enclosed within or integrated with the housing is a switch electrically interconnected between the battery and lamp to modulate power delivery from the battery to the lamp.

The housing of the flashlight is formed of impact-resistant material and defines a battery compartment and a lamp socket, each integrally formed within the housing. In preferred embodiments, the battery compartment is sized and dimensioned to receive at least one disc or button-shaped battery. The lamp socket is positioned within the housing forward of the battery compartment and is sized and dimensioned to receive a contact- or lead-bearing end of the flashlight lamp within the socket.

In specific embodiments of the invention, the battery compartment is defined by a closed ceiling of the housing which has an internal seating surface to seat the discoid battery. The battery compartment is further defined by a generally circular sidewall that extends downward from the ceiling and retains the edges of the battery or batteries within the compartment. Opposite the ceiling, the battery compartment opens at a lower perimeter rim of the sidewall to permit placement and removal of the battery within the compartment. In conjunction with this design, the flashlight features a battery compartment cover or similar closure mechanism that is removably connected to the housing to provide for water-resistant closure and access to the battery compartment.

In more detailed aspects of the invention, the unitary flashlight housing further includes an electrical contact or lead port adapted to receive the electrical connector elements that electrically interconnect the battery terminals and lamp contacts or leads. The electrical contact or lead port is typically formed as a direct opening in the circular sidewall of the battery compartment interconnecting the battery compartment and the lamp socket to allow for the electrical contacts or leads to pass therethrough. Preferably, the electrical contact or lead port is directly interposed between the lamp socket and a forward end of the battery compartment. The electrical contact or lead port is alternatively formed as a direct opening in the circular sidewall of the battery compartment interconnecting the battery compartment and the lamp socket to allow for the lamp and the electrical contacts or leads to pass therethrough. Such a configuration allows the lamp to be inserted through the battery compartment and the port and into the lamp socket.

In other detailed aspects of the invention, the switch that modulates power delivery from the battery to the lamp is a momentary contact switch that includes a flexible ceiling or ceiling member that is manually depressible in a downward direction. This manual depression forces downward deflection of a flexible contact or lead disposed between the ceiling and a flat conductive terminal of the battery and electrically connected to the lamp. This deflection results in a contact being formed between the flexible contact or lead and the battery terminal and complete a power circuit to the lamp. Release of manual pressure on the flexible ceiling or ceiling member causes it to return to a non-deflected position along with the flexible contact or lead, which breaks the contact and turns the lamp off. In more detailed embodiments, the switch incorporates a thin- walled, flexible ceiling member that is an ovate or circular diaphragm integrally formed and centrally disposed within the ceiling. In an alternative embodiment, the switch is a multi-position on-off switch. In other embodiments of the invention, the portable lighting device as summarized above, incorporates a flexible collar interposed between the lamp and lamp socket. The collar is made of a resilient material and is sized and dimensioned to secure the lamp within the socket and to form an effective, water-resistant seal between the lamp and housing. In more detailed aspects, the flexible collar is elongated or adjustable to surround the lamp where it extends from the lamp socket forward of the housing to reduce radial light emission from the lamp. In an alternative embodiment, the collar acts as a shield to prevent radial emission of light. In yet another embodiment, the flashlight comprises a shaped accessory piece which diffuses light from the lamp . In additional embodiments of the invention, the portable lighting device as summarized above includes a multiple function control element as the switch or a component thereof. The multi-function control element has a selectable control mechanism to connect and disconnect power from the battery to the lamp and to select between a plurality of operation modes of the lamp. In certain embodiments, the selectable control means includes a manual switch to control an on-off mode of the lamp and a control circuit, such an analog control circuit, to control a second operation mode of the lamp. For example, the second operation mode may be a flashing mode or stroboscopic mode, and the control circuit may comprise a conventional analog flasher circuit electrically connected to the lamp. In alternative embodiments, the portable lighting device of the invention includes a multiple function control element as above, wherein the selectable control mechanism includes a microprocessor control unit. The microprocessor is functional to control one or more operation modes of the lamp. For example, selectable lamp operation modes controlled by the microprocessor may include one or more of the following: an on- off switched mode; a flashing mode; a stroboscopic mode; a brightening mode; a dimming mode; and/or an auto-off mode. In more detailed aspects, the microprocessor further controls a cycle rate or intensity of the lamp within one or more selected operation mode(s). In exemplary embodiments, the microprocessor controls a brightening or dimming mode having at least two selectable lamp intensity options, a flashing mode having at least two selectable lamp flashing rate options, a stroboscopic mode optionally having an adjustable flashing rate, a multi-color stroboscopic mode, and/or an auto-off mode functional to automatically terminate power to the lamp after a predetermined time of operation. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 provides an exploded perspective view of a miniature flashlight incorporating the concepts of the invention. Figure 2 is a perspective illustration of a unitary housing of a miniature flashlight employing the concepts of the invention.

Figure 3 is a mid-longitudinal sectional view of a miniature flashlight employing the concepts of the invention.

Figure 4 is a longitudinal sectional view of a miniature flashlight employing the concepts of the invention and provided with an optional microprocessor control cassette.

Figure 5 a illustrates an optional microprocessor control cassette adapted for incorporation within a miniature flashlight of the invention.

Figure 5b illustrates an alternative embodiment of a connector strap. Figures 6A and B illustrate an optional microprocessor control cassette and polychromatic lamp.

Figures 7A-C illustrate an optional novelty accessory for use with a flashlight.

Figure 8 is an exploded perspective view of a partially assembled miniature flashlight incorporating the concepts of the invention, including an accessory piece.

Figure 9 is another exploded perspective view of a partially assembled miniature flashlight, including an accessory piece.

Figure 10 is a mid- longitudinal sectional view of a miniature flashlight showing an accessory piece attached to the miniature flashlight.

DESCRIPTION OF THE SPECIFIC EMBODIMENTS

As shown in Figure 1 , the present invention is directed to a novel miniature flashlight 10 which has a compact flashlight housing 12 adapted to enclose at least one miniaturized battery 14 and to secure a miniaturized lamp 16 in electrical connection with the battery. The housing is formed of an impact-resistant material, such as a molded resilient polymer, and may be constructed from multiple components that are welded, interlocked or otherwise integrated to form the housing. However, in a preferred embodiment of the invention, the housing is a unitary structure which typically comprises a single formed or molded body. In more detailed embodiments, the body is formed as a unitary molded thermoplastic body.

A preferred flashlight housing 12 adapted for use within the invention defines at least two internal receptacles or compartments, namely a battery compartment 18 and a lamp socket 20, which are typically integrally formed within the housing (see, e.g., Figs. 1 and 2). In certain embodiments, the battery compartment is sized and dimensioned to receive at least one disc- or button-shaped battery 14. In more detailed aspects, the battery compartment is sized and dimensioned to securely receive one 3 volt, 2032, or two three volt 2016, discoid lithium batteries having dimensions of 20 mm X 3.2 mm or 20 mm X 1.6 mm, respectively.

The lamp socket 20 is positioned within the housing forward (i.e., following the direction of arrow 22 in Fig. 1) of the battery compartment 18 and is sized and dimensioned to receive a contact- or lead-bearing end 24 of the flashlight lamp 16 within the socket. The socket thus has a generally cylindrical side wall 26 to retain the lamp, a rear retaining wall 28 to seat the lamp in a position fully inserted within the socket, and an aperture defined by a generally circular front rim of the socket sidewall.

To interconnect the battery 14 and the lamp 16, the invention incorporates electrical connector elements, for example posts, wires, or leads, that electrically connect contacts or leads of the lamp to battery terminals of opposite polarity to complete an electrical circuit that supplies power from the battery to the lamp. For example, as shown in Figure 3, in one embodiment the invention incorporates electrical connector elements, that electrically connect two contacts or leads 32, 34 of the lamp to two battery terminals 36, 38 of opposite polarity to complete an electrical circuit that supplies power from the battery to the lamp. These electrical connector elements may be continuous leads extending from the lamp in the form of wires or posts, or may be separate elements, such as wire leads, posts, terminals, traces within a printed circuit board or microprocessor, etc., that connect to separate contacts or leads from the lamp and establish continuous or intermittent electrical connections to and from the battery terminals. The electrical connector elements may run internal or external to the housing 12, or they may pass through portions of the housing or be embedded in a wall or other structure of the housing. Alternatively, the electrical connector elements may be integrated within a separate structure attached to or enclosed within the housing, such as a printed circuit board.

In another embodiment, an electrical connector element, interconnecting a battery terminal and a switch or microprocessor, has internal ends 139 that are moveable between connected and disconnected states. In a connected position, current flows along the electrical connector element to the switch or microprocessor. In a disconnected state, the flow of power along the connector element is interrupted. One of the internal ends is typically biased, such as by tension, in the connected position. For example, an end can be biased by using a conductive material having memory or by use of a mechanical element, such as a spring. To keep the element in the disconnected position, a nonconductive material 141, such as a plastic tab, can be inserted between the internal ends of the connector element, such as, for example, to prevent drain on a battery during storage of the flashlight. The nonconductive material 141 can be conveniently removed when the use of the flashlight is desired.

The lamp 16 for use within the miniature flashlight of the invention can be any of a wide range of suitable lamp designs, including single and multiple filament incandescent lamps, light-emitting diodes (LEDs), and laser-emitting illumination devices (coupled with a collimator incorporated within the housing). In preferred embodiments of the invention, an LED lamp is used. The lamp can be any of a wide range of colors, including white, red, yellow, blue, turquoise, green, orange, amber, as well as any other colors or combinations thereof.

In other preferred aspects of the invention, the battery compartment 18 is formed as a uniquely-shaped and dimensioned recess within the housing 12 defined by a closed top wall or ceiling 40 of the housing and a generally circular (i.e., in cross-section) sidewall 42 that extends downward (arrow 44, Fig. 2) from the ceiling and retains top and bottom edges 46, 48 of the battery or batteries from sliding around within the compartment. The battery compartment optionally includes one or more internal seating surface(s) 50 to seat the battery 14 when the battery is inserted into the compartment. The seating surface(s) may simply represent an undecorated inner surface of the ceiling 40 or may be formed as one or more post(s), ridge(s) or other suitable surface feature(s) extending from the ceiling to secure the battery from dislocating or rocking upward or downward within the compartment. In one preferred embodiment, the battery seating surface represents a bottom ridge of a partition 52 extending downward from the ceiling that is generally circular or oval in cross-section. The partition may be a solid surface feature extending from the inner surface of the ceiling. Alternatively, the partition may be formed as a valley or fold 54 in the ceiling wall, e.g., as shown from an exterior surface 56 of the ceiling wall in Fig. 1. In a preferred embodiment depicted in Fig. 2, the partition defines a generally circular or oval sub-compartment 58 within a top-central portion of the battery compartment.

To allow for removal and replacement of the battery 14 within the battery compartment 18, the compartment is provided with an access opening 60 defined by a lower perimeter rim 62 of the battery compartment sidewall 42 opposite the closed ceiling 40. At the same time, in order to securely enclose the battery within the compartment the invention provides a removable battery compartment cover, or similar closure mechanism, that is removably connected to the housing to provide for water-resistant closure and access to the battery compartment. In certain embodiments, the compartment closure mechanism comprises a removable battery compartment cap 64 which can be engaged with or secured to the housing to provide a water resistant closure for the battery compartment. Preferably, the cap is sealably engaged with the housing by a circumferential ridge 66 extending from a perimeter edge 68 of the cap which seats within a circumferential cap-seating groove 70 molded or milled in the sidewall 42 of the battery compartment. The cap-seating groove is sized and dimensioned to securely receive the circumferential ridge of the battery compartment cap and form a water-resistant seal therewith, thus providing for secure closure of the battery compartment. To facilitate removal of the battery compartment cap 64, an optional release tab 72 may be provided extending from the perimeter edge of the cap and sized and dimensioned to fit within a tab recess 74 in the housing adjacent the battery compartment opening.

In certain detailed aspects of the invention, an exterior surface of the housing 12 is molded or worked to provide a smooth surface for stamping, engraving or otherwise imprinting an ornamental or informational design, logo, or trademark to facilitate use and sale of the miniature flashlight 10 as a novelty item or trade issue item to generate consumer goodwill. In one embodiment, the battery compartment cap 64 is provided with a smooth exterior surface 75 for this purpose (see, e.g., Fig. 3). Alternatively, any other external surface of the housing of sufficient size, e.g., between about 1-3 cm, may be rendered during or after manufacture of the housing to provide a smooth surface for decoration. Alternatively, the surface may be decorated or imprinted during manufacture of the flashlight. The surface of the housing 12 and/or battery compartment cap 64 can also be relieved to provide a surface for labeling.

Yet another optional feature of the miniature flashlight of the invention is an attachment ring 76 connected to or integrated within the housing for securing a keyring or lanyard to the flashlight or otherwise tethering or securing the flashlight to a secondary article. As depicted in Figs. 1 and 2, the attachment ring is preferably molded as an integral part of the housing to facilitate manufacturing and provide sufficient strength for the attachment. Ideally, the attachment ring is located at a rear end of the housing, opposite the lamp socket 20. With this construction in mind, it is further desired to orient the optional release tab 72 of the battery compartment cap to extend rearward toward the attachment ring and to locate the tab recess 74 in the housing adjacent the open attachment ring. This design facilitates access to the release tab through the attachment ring opening using a fine screw driver or like tool.

Turning now to the electrical components of the flashlight, the unitary housing 12 described above preferably fully encases the electrical connector elements that connect the lamp contacts or leads to the battery terminals 36, 38. To achieve this construction, the flashlight housing preferably includes an electrical contact or lead port 78 formed as a direct opening through the circular sidewall 42 of the battery compartment 18 and rear retaining wall 28 of the lamp socket 20 interconnecting the battery compartment and lamp socket 20. This port is sized and dimensioned to receive electrical contacts or leads extending from the lamp and to provide for their passage into the battery compartment to complete the electrical connections with the battery. Typically, the electrical connectors are simple leads 32, 34, for example conductive wires or posts, integrally formed with the lamp and continuous with the lamp filament that extend rearward from the lamp into the battery compartment to directly contact the battery terminals. The electrical contact or lead port is preferably directly interposed between the lamp socket and forward end of the battery compartment.

In another embodiment, the electrical contact or lead port 78 is typically formed as an opening in the circular sidewall of the battery compartment interconnecting the battery compartment and the lamp socket 20 to allow for the lamp 16 and the electrical contacts or leads to pass therethrough. Referring to Figures 8 and 9, electrical connectors 32, 34 are electrically connected to electrical connector elements 138 on a control cassette 126. Referring to Figure 9, the assembled lamp 16-control cassette 126 is then inserted into battery compartment 18 such that lamp 16 is inserted into and/or through lead port 78 and into the lamp socket 20. The assembled lamp 16-control cassette 126 can optionally include a locking device 17 to prevent rotation or lateral movement of lamp 16 when connected to control cassette 126. Referring to Figure 8, locking device 17 is typically made of resilient material, such as a resilient plastic. The locking device 17 typically has a slot 19 formed partially across its radius. Slot 19 is adapted to fit over electrical connectors 32, 34, such as by sliding the locking device 17 over those connectors. The outer diameter of the locking device 17 usually securely engages (such as by a compression fit) the inner surface of lead port 78 and/or lamp socket 20 to prevent rotation or lateral movement of the lamp 16.

In a preferred embodiment of the invention, the electrical connection between the battery 14 and lamp 16 is formed by a first elongate lead 32 and a second elongate lead 34 extending from the lamp 16 rearward through the lead port 78 into the battery compartment 18 to contact the two battery terminals 36, 38 (see, e.g., Figs. 1 and 3). The first lead is positioned and secured within the battery compartment to form a contact with a first conductive terminal 36 of the battery, and the second lead is positioned and secured in the compartment to form a switchable contact with a second conductive terminal 38 of the battery. In more detailed aspects, the first elongate lead extends through the contact or lead port and is reflected laterally against the circular sidewall 42 of the battery compartment to securely position the first lead at the forward end of the compartment to contact the first conductive terminal at a front- facing, lower perimeter edge 80 of the battery (see, e.g., Figs. 2 and 3).

Optionally, a first lead stanchion 82 may be provided to retain the first lead 32 in a secure position near the lower perimeter rim 62 of the battery compartment 18. As shown in Figure 2, the first lead stanchion is in the form of a post or revetment protruding from the circular side wall 42 that prevents upward deflection of the first lead toward the battery compartment ceiling 40. This stanchion configuration to secure the first lead position within the compartment is particularly desirable when two batteries are employed in the flashlight. As noted above, an optional battery configuration is to use two discoid (e.g., coin-shaped) coin cells — with a top cell adjacent the ceiling seated on a battery seating surface 50 and a bottom cell stacked below the first cell in the same orientation, e.g., with both negative terminals facing upward. In this configuration, the first battery terminal 36 for connection to the first lamp lead 32 is located at the front- facing lower perimeter edge 80 of the bottom cell, and the second terminal 38 is at the flat upper surface of the top cell. The stanchion then, functions to engage a reflected contact end 84 of the first elongate lead to prevent upward movement of the first lead contact end toward the ceiling of the housing — holding the lead in contact with the first terminal and preventing a short by aberrant contact with other surfaces of the top or bottom cells.

In the general preferred embodiment described above, having a first lead

32 that contacts a front- facing lower perimeter edge 80 of the single or bottom-positioned battery 14, the second lead 34 is positioned and secured in the compartment to form a switchable contact with the second conductive terminal 38, which is disposed at the flat upper surface of the single or the top-positioned battery. In more detailed aspects, the second elongate lead 34 extends through the contact or lead port 78 rearward into the battery compartment adjacent the ceiling 40 of the housing 18 and is positioned and secured to form an intermittent, switchable contact with the second terminal. Positioning the second lead relative to the second conductive terminal may be accomplished by providing a suitably malleable lead element (e.g., a wire or post of suitable gauge) to allow for deformation of the lead element during assembly to follow a predetermined path from the lamp 16 through the lead port to a position adjacent the second terminal. To ensure that the second lead is securely maintained in this desired position, the lead element has sufficient stiffness to hold a flexible contact end 84 of the lead in place, i.e., in a rest position proximal to the second terminal and preferably medially disposed relative thereto. At the same time, the lead element has sufficient flexibility and memory to allow for manual deflection of the flexible contact end (see below) from the rest position to move the lead end in contact with the second conductive terminal, whereafter upon release of manual deflective pressure the lead will return to substantially the same rest position out of contact with the terminal.

In more detailed embodiments, a second lead-positioning element 86 may be provided to further secure a flexible contact end 84 of the second lead 34 in a rest position approximately centered above the second battery terminal 38 (see, e.g., Figs. 2 and 3). The lead-positioning element is typically formed as one or more posts or ridges extending downward from the ceiling 40 of the housing 12 at approximately a central position of the ceiling. Preferably, it is formed as a v- or bridge-shaped element as shown in Fig. 2, so that the end of the lead seats in a central groove or on a central span 88 of the positioning element and is straddled and secured against lateral displacement by paired lateral ridges or posts 90. Thus constructed, the second lead positioning element functions not only to secure the lead end in position, but also as part of an alternate switching mechanism for the flashlight, as discussed in further detail below.

The portable lighting device of the invention may incorporate a variety of useful switches adapted to meet the above-stated objectives of cost efficiency, ease of operation, and diversity and flexibility of function. The basic function of the switch is to modulate power delivery from the battery to the lamp. However, this general function can be readily achieved using different configurations and sources for electrical connection and control.

In one preferred embodiment of the invention, the switch is a momentary contact switch that includes a flexible ceiling 40 or ceiling member of the housing 12 that is manually depressible in a downward direction. This depression forces downward deflection of the flexible contact end 84 of the second elongate lead 34 to form the switchable contact with the second conductive terminal 38 of the battery. To achieve this purpose, at least a central portion of the ceiling is flexible and subject to downward deflection by a height of at least 0.25-0.5 mm, preferably between 0.5-1.0 mm or greater, when the central portion of the ceiling is engaged and depressed manually, e.g., by engagement and flexure of a person's thumb or forefinger. Typically, the downward deflective movement is translated to the second lead via the second lead-positioning element 86 that extends downward from the ceiling and is centered above the second battery terminal 38, e.g., by downward deflective contact from the central span 88 of the positioning element forcing the contact end of the lead downward. Release of manual pressure on the flexible ceiling or ceiling member causes the ceiling and positioning element to return to a non-deflected position, along with the flexible contact or lead, which breaks the contact and turns the lamp off.

To facilitate the foregoing switching design, flexibility may be imparted to the entire ceiling 40 by choice of appropriate materials, e.g., by choosing suitably flexible thermoplastics. However, the goal of providing a durable and impact resistant housing 12 render it more preferable to provide flexibility to only a portion of the ceiling, for example by using different materials or conditions to achieve lesser hardness and greater flexibility in the central portion versus the perimeter of the ceiling or remainder of the housing. Alternatively, the thickness of a medial wall portion 92 of the ceiling may be selected to achieve flexibility for the portion of the ceiling overlying the second lead 34, while a perimeter wall portion 94 of the ceiling may be selected to have a greater thickness for increased durability and impact resistance (see, e.g., Fig. 3).

Thus, as shown in Fig. 1, a preferred embodiment of the invention incorporates a thin-walled diaphragm 96 as an integral member of the ceiling. The diaphragm is typically ovate or circular and disposed centrally above the second conductive terminal of the battery 38. It is flanked around its perimeter by a thicker walled portion 94 of the ceiling, and is optionally segregated therefrom by a valley or fold 54 in the ceiling wall. Preferably, the diaphragm is recessed relative to the surrounding perimeter wall portion of the ceiling, e.g., by having a thinner walled construction as described above, to prevent inadvertent actuation of the switch, for example when the light is stowed adjacent an object that impinges against the ceiling.

The valley or fold 54 that structurally outlines the diaphragm 96 facilitates visual recognition of the diaphragm as a depressible switch "button". Unlike separate button elements known in the art, the diaphragm of the instant invention is an integral part of the housing 12, which design provides for improved efficiency of manufacturing and increased water-and dust-resistance of the flashlight interior. In addition, employment of a valley or fold to structurally outline the diaphragm provides an alternate means to increase flexibility of the diaphragm to facilitate depression of the second lead contact end 84 against the second battery terminal 38. Without further reducing the wall thickness of the diaphragm, depression of the diaphragm may be facilitated by flexure, or separation, of the opposing valley or fold walls. As noted above, the valley or fold outlining the diaphragm may also serve the functions of providing an internal seating surface 50 to seat the battery 14 when the battery is inserted into the battery compartment 18, and to define a generally circular or oval sub-compartment 58 within a top-central portion of the battery compartment to house one or more additional components of the flashlight. In various embodiments of the invention, all or a portion of the flexible ceiling or diaphragm 96 is decorated with a rugose or ridged exterior surface to enhance manual engageability and flexibility of the ceiling, ceiling member or diaphragm. For example, as shown in Fig. 1, the exterior surface of the diaphragm may be molded or milled to bear concentric grooves and ridges 98 that reduce the surface tension of the center wall portion 92 of the ceiling to enhance flexibility, and also allow for improved gripping of the surface by the user's thumb or forefinger.

In certain embodiments of the invention, the miniature flashlight is equipped with a flexible ring, sleeve, or collar 100 that at least partially surrounds a sidewall 102 portion the lamp 16 and is interposed between the lamp and the cylindrical sidewall 26 of the lamp socket 20 (see, e.g., Figs. 1 and 3). The ring, sleeve or collar is formed of a resilient material, for example a thermoplastic or rubber material, and is sized and dimensioned to surround at least a portion of the lamp sidewall and to fit within the cylindrical sidewall of the socket to secure the lamp snugly within the socket. Preferably, the ring, sleeve or collar is compressible to form an effective, water-resistant seal between the ring, sleeve or collar and housing by way of a compression fitting, wherein the ring, sleeve or collar has approximately the same compressibility to form the seal as is provided by a conventional rubber, plastic or Teflon ring seal. In more detailed aspects, the flexible ring or collar seats within a circumferential groove 104 molded or milled in the sidewall of the socket which is sized and dimensioned to receive a perimeter portion of the ring or a perimeter ridge 106 extending from the sleeve or collar. When a sleeve or collar is used, the perimeter ridge is positioned on the sleeve or collar so that it seats within the circumferential groove in the socket sidewall when the sleeve or collar is fully inserted into the socket so that a rear seating end 108 of the sleeve or collar seats against a collar seating abutment 110 recessed in the socket.

In one embodiment, the sleeve or collar 100 that partially or fully surrounds the sidewall 102 of the lamp 16 allows for shielding of lateral light emission from the lamp (see, e.g., Figs. 1 and 3). This is particularly useful when the flashlight is employed for covert illumination, for example in the context of police work or to provide illumination in theaters or other darkened public venues without discourtesy to others. For use in these contexts, the sleeve or collar may be selected in a variety of lengths to partially or fully surround the lamp sidewall. To optimize this utility, the collar is opaque and is sized or adjustable to fully surround the sidewall and/or a distal tip 112 of the lamp, so that light is only emitted in a forward direction from a distal aperture 114 of the collar. To provide for adjustability in the collar length, the collar may be constructed of multiple elements with at least one distal element adapted to telescope relative to a proximal element that remains engaged in the socket. Alternatively, the aperture-bearing end of the collar may be adjusted relative to the distal tip of the lamp by sliding the collar forward or backward within the lamp socket.

In other detailed aspects of the invention, the flexible sleeve or collar 100 seats flush with, or extends only slightly (e.g., 1-5 mm) from, a front face 115 of the housing (see, e.g., Fig. 4). A front end 116 of the collar may be parallel to the front of the housing, or it may be tapered in a forward direction toward a center axis (arrow 117) of the housing as shown in Fig. 4. In one preferred embodiment, the collar is made of a translucent material and its front end is tapered toward the center axis to provide for lateral transmission and refraction of light to enlarge the apparent area of illumination when the light is viewed from a distance (e.g., for emergency rescue use). This function may be enhanced by providing facets 118 or other refracting surface texturing to further disperse light in a lateral direction away from the center axis.

In another embodiment, the sleeve or collar 100 surrounds the lamp 16 and shields diffuses the light from the lamp 16. This is useful when a dimmer or softer beam of light is desired, such as for example for covert illumination, or to blend different colors of light from a polychromatic lamp. For use in these contexts, the sleeve or collar may be selected in a variety of lengths to fully surround the lamp sidewall. To optimize this utility, the collar is typically translucent and is sized or adjustable to fully surround the sidewall and distal tip 112 of the lamp.

In still another embodiment, the diffuser further comprises a shaped accessory piece to augment light emitted from the lamp 16. The diffuser can have a variety of novelty shapes, including for example flame shapes, animal shapes, religious symbol shapes and the like. The accessory can be shaped in two or three dimensions. The accessory piece can be translucent or transparent. For example, referring to Figures 7A, 8 and 9, such a diffuser can comprise a flame-shaped accessory piece 190 which is transparent or translucent. Such a diffuser can formed of multiple pieces, e.g., first 192 and second 194 interlocking diffuser elements, as depicted in Figures 7B and C. Alternatively, the accessory piece can comprise a single element. Light emitted from a lamp 16 (e.g., a monochromatic or polychromatic lamp) is augmented by the shape and/or pattern of the accessory piece. For use in this context, the accessory piece may be selected from a variety of lengths or shapes and can attach to a collar or sleeve, or can attach to the lamp socket 20. The accessory piece can also attach to an annular ring 105 on sleeve or collar 100. Accessory piece 190 has a connector end 195 with a corresponding groove 107 to engage the annular ring 105. Referring to Figure 10, the connector end 195 can partially or completely surround or engage sleeve or collar 100. In another embodiment, a mounting socket or notch 196 is provided in the connector end 195 of the diffuser for seating over the lamp 16. Such an accessory piece is optionally removable.

In other preferred embodiments of the invention, a single function on/off switch as described above is supplemented or replaced by, or integrated with, a multiple function control device 120 (see, e.g., Fig. 4). This control device includes one or more selectable control mechanisms that function as an on-off switch to selectably connect and disconnect power from the battery or batteries 14, 14' to the lamp 16 (for example in the manner of the single function switch described above), and/or as a controller that regulates one or more additional operation modes of the lamp. For example, the second operation mode may be a flashing mode, and the analog control circuit may comprise a conventional flasher circuit electrically connected to the lamp. The second operation mode may also be a stroboscopic mode and the control circuit may comprise a digital oscillator or stroboscopic circuit electrically connected to the lamp. Additional operation modes that may be controlled by the multiple function control device include, but are not limited to, a brightening mode; a dimming mode; and an auto-off mode.

In certain embodiments of the invention, the selectable control mechanism includes a microprocessor control unit 124 that functions to control one or more operational modes of the lamp (see Fig. 4). The microprocessor unit may be integrated within a wall of the housing 12 or affixed to the housing, preferably within an interior space defined by the housing, provided that the location of the microprocessor element allows for proper electrical connections to be made between the battery 14, lamp 16, and the microprocessor unit. Typically, the microprocessor 124 is incorporated in an electronic board or cassette 126 formed of non-conductive material that is specially fitted for secure enclosure within the housing and which can optionally be removed for replacement and interchanging with different cassettes having different control functions. In certain embodiments, the microprocessor cassette is fitted within a cavity defined by the housing and located above the battery 14 or batteries within the battery compartment 18, which can include the generally circular or oval sub-compartment 58 within the top-central portion of the battery compartment defined by the partition, e.g., valley or fold 54, in the ceiling wall, as described above (see, e.g., Figs. 1, 2, and 4). In one embodiment, the cassette is closely fitted within this subcompartment and is retained within the housing by one or more retaining elements 128 (e.g., an interlocking groove or ridge, peg, snap- fitting, tab, etc.) connected to the housing that securely interlock or receive a mounting element 130 (e.g., a mated ridge, groove, peg-hole, slot, etc.) integrated with the cassette (see, e.g., Figs. 2 and 5, depicting interlocking pegs 128 and peg holes for mounting the cassette — note that the second lead positioning element 86 is not used in conjunction with this embodiment).

The electrical connections interconnecting the battery 14 or batteries, lamp 16 and microprocessor 124, and the design and circuitry of the microprocessor, can be routinely configured among different embodiments of the invention in accordance with general methods and materials known in the art. For convenience and ease of understanding, one preferred electrical design involves interconnection of a first elongate lead 32 from the lamp to the battery in a similar construction as described above. Thus, the first lead extends from the lamp 16 rearward through the lead port 78 into the battery compartment 18 to contact the first conductive terminal 36 of the battery at a front- facing, lower perimeter edge 80 of the battery (lower battery 14' in Fig. 4). The second lead 34 of the lamp can be secured to an electrical connector, such as a trace 138, on the front of the control cassette 126. Alternatively, both leads 32, 34 of lamp 16 can be electrically connected to electrical traces 138 on control cassette 126. One or more conductive lead traces 138 interconnect the lead 32, or 32 and 34, with the microprocessor, and optionally with a manual, dedicated function on-off switch 140 located toward a rear end 142 of the control cassette 126. This optional switch is typically a simple pressure switch that completes a circuit through the trace 138 to the front terminal to activate the lamp when the flexible diaphragm 96 that overlies the switch is depressed. In one embodiment, this switch can be activated independently of the microprocessor to bypass the microprocessor circuitry and provide high power illumination on immediate demand. Such an embodiment can optionally be further combined with a biased electrical connector element having biased, internal ends 139 (see, e.g., Fig. 5a) to keep the ends in contact with each other (i.e., in the connected position). A nonconductive plastic pull-tab 141 is inserted between the internal ends 139 of the electrical connector element during storage to prevent drain on the battery. The pull- tab 141 can be removed to allow the internal ends 139 to contact each other, and thereby provide power to a switch or microprocessor. For example, the pull tab 141 can be removed when the flashlight is removed from storage. A by-pass switch can optionally allow the flashlight to be activated during storage. In another embodiment, the activation of the switch 140 modulates power to the microprocessor and the light, and thus acts as an on-off switch for the flashlight.

Depending on the circuit configuration, the microprocessor 124 and/or the dedicated on-off switch 140 are electrically connected to the second conductive terminal 38 of the battery (e.g., at a flat, upper surface of the top battery 14). This can be achieved in a number of ways, for example by forming and connecting a conductive trace from each the microprocessor and/or dedicated switch, through the non-conductive cassette body, to a conductive layer 144 or surface coating, e.g., copper, on an underside of the board adjacent the second terminal. In order to ensure that electrical contact between this terminal and the microprocessor is not broken even momentarily, it is desirable to include one or more conductive pins or spring-action nodes 146 protruding from the underside of the cassette, which nodes are conveniently provided by incorporation of commercially available pressure switches to actuate the microchip and the dedicated on/off switch.

To complete the power circuit for the microprocessor unit 124, the invention optionally further incorporates a novel connector strap 150 (Fig. 5a) which extends laterally and downward from the control unit cassette 126 and provides an electrical connection through the strap and board, e.g., via a separate trace 138 to the microprocessor, between the microprocessor and the first conductive terminal 36 along a perimeter edge of the battery (bottom battery 14' in Fig. 4). In preferred embodiments, the strap is uniquely sized and dimensioned for accommodation within the housing and features a lateral extending arm 152, a downward extending segment 154 and a medially reflected terminal arm 156 that collectively span the battery or batteries adjacent the battery compartment sidewall 42 and make an electrical contact with the first conductive terminal 38 of the battery (or bottom battery 14'). The laterally extending arm 152 and downwardly extending segment 154 are advantageously shielded from contact with the battery that underlies and is in electrical contact with the conductive layer 144 forming the undersurface of the cassette. This can be achieved by providing an insulating outer layer to the strap. However, in the interest of providing a more compact design for the flashlight, the laterally extending arm and downwardly extending arm preferably rest within first and second recesses 158, 159 that are milled or molded into the battery seating surface 50 and battery compartment sidewall 42. These recesses are deep enough to receive the strap, which is preferably between about .010 and .015 inches, in a seated position where the strap is recessed from the exposed surfaces of the housing to protect the strap from electrical contact with the battery, without compromising the water resistant design of the housing.

In an alternative embodiment, leads 32 and 34 of lamp 16 are both electrically connected to control cassette 126 (see, e.g., Figs. 8 and 10). A connector strap 150 (e.g., Fig. 5b) extends laterally and downward from the control unit cassette 126 and provides an electrical connection through the strap and board, e.g., via a separate trace 138 to the microprocessor, between the microprocessor and the first conductive terminal 36 along a perimeter edge of the battery (e.g., bottom battery 14' in Fig. 4). A second electrical connection is provided through a second conductive terminal 38 of the battery. The strap is typically sized and dimensioned for accommodation within the housing and features a lateral extending arm 152, a downward extending segment 154 and a medially reflected terminal arm 156 that collectively span the battery or batteries adjacent the battery compartment sidewall 42 and make an electrical contact with a side portion of a battery. In particular, tabs on terminal arm 156 can make electrical contact with the perimeter edge of the battery. In some embodiments, the laterally extending arm 152 and downwardly extending arm 154 can rest within first and second recesses 158, 159 that are milled or molded into the battery seating surface 50 and battery compartment sidewall 42. These recesses are typically deep enough to receive the strap.

Actuation of the microprocessor 124, as well as selection of different operating modes, frequencies and intensities of the lamp 16 controlled by the microprocessor, may be implemented by one or more, manually, electrically or remotely actuated switching devices. Typically, a single microprocessor switch 160 is used to actuate the microprocessor and select mode and other functional changes for the lamp. In one preferred embodiment, the microprocessor control switch is located toward the front end of the control cassette 126 and is actuated by depression of the diaphragm 96 in a forward portion of the diaphragm. This depresses the switch and selects a first mode of operation of the lamp. Continued depression of the switch for a pre-set time period that determines a selection change by the microprocessor, may select a different intensity or frequency of lamp operation. The pre-set period for determining a mode or intensity or frequency change is typically between about 1-10 seconds, preferably between about 2-5 seconds, and more preferably about 4 seconds. Alternatively, continued depression of the switch may select a second operation mode of the lamp, followed upon expiration of the set selection time period by a third operation mode, then a fourth mode, etc.

Selection of the microprocessor switch or dedicated on/off switch 140 is optionally facilitated by incorporation of a fulcrum-type ridge or protrusion 162 extending from the top of the cassette near the front-to-rear midline of the cassette and aligned with a center of the diaphragm. This facilitates user selection (initiated by a forward- or rearward-biased manual depression of the diaphragm) of the front, microprocessor control switch, or the rear, dedicated on/off switch, respectively. The fulcrum function may be provided by a bead of protective epoxy or other non-conductive material on the surface of the cassette under which the microprocessor 124 is housed or embedded.

Through the application of conventional microcircuitry design, in conjunction with the teachings of the invention, the microprocessor 124 may be designed to control a wide variety of selectable modes and functions of the flashlight. As noted above, exemplary modes include a flashing mode; a stroboscopic mode, a multi-color stroboscopic mode, a brightening mode; a dimming mode; and/or an auto-off mode. In one exemplary embodiment, selectable lamp operation modes controlled by the microprocessor are sequentially ordinated and selected by continuous depression of the microprocessor switch 160 as follows. A first, on/dimming mode is activated by initial depression of the microprocessor switch while the microprocessor is in a powered, resting state. This powers the lamp at a maximal intensity. Continued depression of the switch, e.g., for a pre-set selection change delay period of about 2-5 seconds and preferably about 4 seconds, determines selection of a lower intensity, followed by a third intensity level. Upon expiration of these three selection periods, the microprocessor determines selection of a second operation mode, in this example a flashing mode. In the first flashing mode selection period the lamp flashes rapidly. In second and third flashing mode selection periods the lamp flashing rate gets sequentially slower. Release of the switch, i.e., by termination of manual pressure on the switch, fixes the setting of the lamp mode and frequency or intensity at the last setting determined during the scroll-through sequence.

In an alternative embodiment, actuation of the microprocessor 124, and selection of different operating modes, frequencies and/or intensities of the lamp 16 controlled by the microprocessor, may be implemented by repeated actuation of a microprocessor switch 160 or dedicated switch. Each actuation selects a different mode or other functional change for the lamp. In one preferred embodiment, the microprocessor control switch 160 is located toward the front end of the control cassette 126 and is actuated by depression of the diaphragm 96 in a forward portion of the diaphragm. This depresses the switch and selects a first mode of operation of the lamp. A subsequent depression of the switch signals a selection change to the microprocessor such as a change in intensity or frequency of lamp operation. Alternatively, a subsequent depression of the switch may select a second operation mode of the lamp, etc. For example, the first, on mode is activated by initial depression of the microprocessor switch while the microprocessor is in a powered, resting state. This powers the lamp at a maximal intensity. A second depression of the switch determines selection of a lower intensity. A third depression optionally determines selection of a third intensity level. Another depression can determine selection of another operation mode (e.g., a stroboscopic, a flashing mode or an off mode). In a similar manner, repeated actuation of the switch signals the microprocessor to scroll through any combination of modes and/or functions, including any combination of one or more on-off modes, flashing modes, stroboscopic modes, brightening modes, dimming modes and/or auto-off modes.

One particularly preferred mode of operation to include among the selectable modes determined by the microprocessor 124 is an automatic shut-off or auto- off mode. This control function of the microprocessor activates the lamp for a short term set period, for example 1-3 minutes, after which the lamp 16 is automatically shut off. This allows the user to select a short period of lighting without having to manually re- access the microprocessor switch 160 to shut the light off after the desired lighting period. Thus, for example the user can set the flashlight on a night stand in auto-off mode and then walk across the lit room to bed with only a brief period before the controller executes the auto-off end function. This mode also provides a safety feature that prevents exhaustion of battery power when the lamp is inadvertently activated, e.g., when the flashlight is stowed in a pack and the microprocessor switch impinges against a hard object. Whereas the lamp will automatically come on and stay on (e.g., continue flashing) in any other of the selected modes, if the light is stored in auto-off mode it will only activate the light for a preset, auto-off delay period, for example between about 1-3 minutes, before the controller automatically terminates power to the lamp 16. The auto- off control preferably represents the last mode in a series of function modes that can be selected. Also preferably, a fast-flashing or stroboscopic activation of the lamp mode is set by the microprocessor to initiate as well as terminate the auto-off mode to warn users that a disruption of light omission will imminently occur.

Another particularly preferred mode of operation is a flashing or stroboscopic mode. The control functions of the microprocessor 124 activate the lamp 16 to flash at a preset, variable or random flashing rate. For example, the lamp 16 can be flashed at a rate of 1-60 times per minute (about 0.6 Hz to about 1 Hz), as well as greater and lesser flashing rates. Alternatively, in a stroboscopic mode, the lamp can be flashed at a rate of about 2 Hz to about 2 kHz, or more. Microprocessors with control functions for flashing or stroboscopic modes are generally known in the art. (See, e.g., U.S. Patent No. 5,844,377, which is incorporated by reference herein.)

Another particularly preferred mode of operation is a polychromatic stroboscopic mode in which the microprocessor 124 controls the flashing of individual elements 173 of a multi-element lamp 16 . Each lamp element 173 emits a different color light. The control functions of the microprocessor 124 activate the individual lamp elements 173 to flash in a preset, variable or random order. The flashing rate of the individual lamp elements 173 can be varied, however. Preferably, the flashing rate of the lamp elements 173 is above the critical flicker fusion frequency of a stationary viewer. The critical flicker fusion frequency (also known at the flicker fusion frequency threshold) is the point at which flicker becomes visually perceptible. When the flashing rate of the individual lamp elements 173 is above the critical flicker fusion frequency, the lamp appears to the viewer to continuously emit light, rather than flashing. As a result, the light emitted by the lamp elements appears to the viewer to be the combination of the individual colors of the lamp elements 173, i.e., a secondary color. For example, if the lamp elements are red, green and blue, the observed secondary color is white.

The individual flashes of a lamp that flickers above the critical fusion frequency can be separated, however, by moving the lamp in a linear or curvilinear pathway. For example, if the lamp 16 is held stationary relative to the viewer the second color is perceived (e.g., white light). In contrast, if the lamp is moved in a linear or curvilinear path relative to the viewer, light from the individual lamp elements is perceived by the viewer (e.g., as red, green and blue light).

Referring to Figs. 6 A and B, an exemplary design of the circuit board layout for a polychromatic stroboscopic flashlight is depicted. The lamp 16 has three lamp elements 173. Each lamp element 173 is an LED emitting red, green or blue light. The microprocessor 124 is a 5 channel oscillator. The oscillator is electrically connected to the individual lamp elements 173 (i.e., individual LED's) as follows: Channel 1 of the oscillator drives the first lamp element 173 (e.g., the red LED). Channels 2 and 5 drive the second lamp element 173 (e.g., the green LED), and channels 3 and 4 drive the third lamp element (e.g., the blue LED). The control functions of the microprocessor 124 activate the individual lamp elements to flash at a preset or variable (e.g., random) rate and/or order. In this example, the lamp elements 173 are cyclically flashed in the order red, green, blue. Power to the microprocessor is provided through contacts 182, which connect to the positive pole of the battery, and connector strap 150, which connects to the negative pole of the battery. Power to the microprocessor 124 is modulated by an on-off switch 185, which is electrically interconnected between one pole of the battery and the microprocessor 124. As necessary, a resistor can be connected between electrical contacts 187.

In other embodiments, by varying the flashing rate and/or color of the individual lamp elements 173, the viewer may observe numerous color alternating patterns. For example, when the lamp is moved relative to a viewer, the viewer can see the bright individual colors of the lamp elements, with dark pauses between the colors, bright partial secondary colors (in which two or more colors are simultaneously present), and bright secondary color (in which all of the colors are simultaneously present). Thus, by moving the polychromatic lamp 16 sufficiently rapidly relative to the viewer, visually striking, intriguing, and/or pleasing multicolored illuminated displays may be produced by a light source which appears monocolored when moving relatively slowly relative to the viewer.

In yet additional embodiments of the invention, an external switching or control device 170 means may be connected or otherwise functionally integrated with the miniature flashlight 10 to provide external control over the mode or frequency or intensity selection, effected through the microprocessor 124 or independently through a separate control circuit that bypasses the microprocessor (see, Fig. 2). Functional connection between the lamp control circuitry and the remote control device may be by conventional electrical control connections, e.g., conventional wire 172, input adapter 174 and input receiver 176 connections or alternative remote connections incorporating, e.g., conventional infrared (IR), radio frequency (RF), internet, intranet, direct connect remote access, satellite, or laser devices for signal transmission, reception and integrated control. Thus, in one embodiment a direct wire remote provides a direct on/off switch function, whereby the light may be placed on a surface or mounted (e.g., by Velcro or other attachment means) to an object such as a firearm barrel, and controlled by a separate control unit 170 having one or more manual selector buttons 178 or like switch elements which may be separately held or attached, e.g., to a firearm grip or stock. Alternatively, the remote control device may be similar to a standard IR television remote with an infrared transmitter and receiver functioning as the input and receiver elements.

While the invention has been described with reference to specific embodiments, the description is illustrative of the invention and is not to be construed as limiting the invention. Various modifications and applications may occur to those skilled in the art without departing from the true spirit and scope of the invention as defined by the appended claims.

Claims

WHAT IS CLAIMED IS:

1. A portable lighting device comprising:

a flashlight lamp having electrical contacts or leads;

a discoid battery having conductive terminals of opposite polarity;

a unitary housing formed of impact-resistant material defining a battery compartment and a lamp socket each integrally formed within the housing, the battery compartment sized and dimensioned to receive at least one discoid battery, the lamp socket positioned within the housing forward of the battery compartment and sized and dimensioned to receive a contact- or lead-bearing end of the flashlight lamp therein;

electrical connection means to electrically connect terminals of the battery with the lamp contacts or leads to complete an electrical circuit supplying power from the battery to the lamp; and

switching means electrically interconnected between the battery and lamp to modulate power delivery from the battery to the lamp.

2. The portable lighting device of claim 1 , wherein the battery compartment is defined by a closed ceiling of the housing having an internal seating surface to seat the battery and by a generally circular sidewall adjoined to the ceiling and extending downward therefrom to retain the battery circumferentially within the compartment, the sidewall having an open lower perimeter rim defining a battery compartment opening to permit placement and removal of the battery within the compartment, further comprising battery compartment closure means removably connected to the housing to provide for water-resistant closure and access to the battery compartment.

3 . The portable lighting device of claim 1, wherein the battery compartment closure means comprises a battery compartment cap having a circumferential ridge extending from a perimeter edge of the cap, and wherein the circular sidewall of the housing defines a circumferential groove proximal to the open lower rim of the sidewall adapted to securely receive the circumferential ridge of the battery compartment cap and to form a water-resistant seal therewith and provide for secure closure of the battery compartment.

4. The portable lighting device of claim 3, wherein the battery compartment cap has a release tab extending from the perimeter edge of the cap that fits within a tab recess in the housing adjacent the battery compartment opening to facilitate removal of the cap for battery replacement.

5. The portable lighting device of claim 1, wherein the unitary housing further defines an electrical contact or lead port adapted for receipt of electrical contacts or leads for electrically interconnecting the battery terminals and lamp contacts or leads.

6. The portable lighting device of claim 5, wherein the electrical contact or lead port comprises an opening in the circular sidewall interconnecting the battery compartment and lamp socket for passage of the electrical contacts or leads therethrough.

7. The portable lighting device of claim 6, wherein the electrical contact or lead port is directly interposed between the lamp socket and a forward end of the battery compartment.

8. The portable lighting device of claim 5, wherein the electrical connection means comprises first and second, elongate leads extending from the contactor lead-bearing end of the flashlight lamp through the contact or lead port, the first lead positioned and secured within the battery compartment to form a contact with a first conductive terminal of the battery, the second lead positioned and secured to form a switchable contact with a second conductive terminal of the battery.

9. The portable lighting device of claim 8, wherein the first elongate lead extends through the contact or lead port and is reflected laterally against the circular sidewall to securely position the first lead at a forward end of the battery compartment to contact the first conductive terminal at a front, perimeter edge of the battery.

10. The portable lighting device of claim 9, further comprising a first lead stanchion positioned lateral to the contact or lead port to engage a reflected contact end of the first elongate lead to prevent upward movement of the first lead contact end toward the ceiling of the housing.

11. The portable lighting device of claim 8, wherein the second elongate lead extends through the contact or lead port rearward into the battery compartment adjacent the ceiling of the housing and is positioned and secured to form a switchable contact with the second conductive terminal of the battery which is disposed at a flat, upper surface of the battery.

12. The portable lighting device of claim 11, further comprising a lead- positioning element extending downward from the ceiling of the housing and having a pair of lateral guide ridges to position and secure the second elongate lead to form the contact with the second conductive terminal of the battery.

13. The portable lighting device of claim 11 , wherein the switch means to modulate power delivery from the battery to the lamp comprises a flexible ceiling or ceiling member that is manually depressible in a downward direction to force downward deflection of a flexible contact end of the second elongate lead to form the contact with the second conductive terminal of the battery, said contact being broken upon release of manual pressure on the ceiling or ceiling member which allows flexible return of the ceiling or ceiling member and contact end of the second lead to a non-deflected position.

14. The portable lighting device of claim 13, wherein the switch means comprises a thin-walled, flexible ceiling member comprising an ovate or circular diaphragm integrally formed and centrally disposed within the ceiling.

15. The portable lighting device of claim 14, wherein the flexible ceiling member has an external surface decorated by concentric grooves and ridges to enhance manual engageability and flexibility of the flexible ceiling member.

16. The portable lighting device of claim 1, wherein the unitary housing further defines an electrical contact or lead port adapted for insertion of the flashlight lamp therein.

17. The portable lighting device of claim 1, further comprising a flexible collar interposed between the lamp and lamp socket, the collar made of a resilient material and being sized and dimensioned to secure the lamp within the socket and form an effective, water-resistant seal between the lamp and housing.

18. The portable lighting device of claim 17, wherein the flexible collar is elongated or adjustable to surround a portion of the lamp extending from the lamp socket forward of the housing to reduce radial light emission from the lamp.

19. The portable lighting device of claim 1, wherein the switching means comprises a switch to control an on-off mode of the lamp.

20. The portable lighting device of claim 19, further comprising a microprocessor to control an operation mode of the lamp.

21. The portable lighting device of claim 20, wherein the operation mode is flashing, stroboscopic, dimming, brightening or auto-off.

22. The portable lighting device of claim 21 , wherein the operation mode is stroboscopic.

23. The portable lighting device of claim 22, the microprocessor having a plurality of channels; the lamp comprising at least two lamp elements, each lamp element comprising a light emitting diode and emitting a different color; and wherein the channels of the microprocessor are electrically connected to individual lamp elements.

24. The portable lighting device of claim 23, wherein the colors emitted by the lamp elements are red, green and blue.

25. The portable lighting device of claim 24, wherein the microprocessor controls the flashing rate of the lamp elements, the flashing rate being above a critical flicker fusion frequency of a viewer; wherein the light emitted by the individual lamp elements appears to a viewer to be a predominantly a secondary color when the lamp is stationary relative to the viewer; and wherein the colors emitted by the individual lamp elements are separately perceived by the viewer when the lamp is moved rapidly relative to the viewer.

26. The portable lighting device of claim 1, wherein the switching means comprises a multiple function control element having selectable control means to connect and disconnect power from the battery to the lamp and to select between a plurality of operation modes of the lamp.

27. The portable lighting device of claim 26, wherein the selectable control means includes a manual switch to control an on-off mode of the lamp and an analog control circuit to control a second operation mode of the lamp.

28. The portable lighting device of claim 27, wherein the second operation mode of the lamp is a flashing mode, and wherein the analog control circuit comprises a flasher circuit electrically connected to the lamp comprising a switching transistor serially connected between the battery and lamp and a switching transistor control network including a control transistor and a resistor-capacitor network functionally interconnected to effect a controlled flashing operation mode of the lamp.

29. The portable lighting device of claim 28 the analog control circuit having a plurality of channels; the lamp comprising at least two lamp elements, each lamp element comprising a light emitting diode and emitting a different color; and wherein the channels of the analog control circuit are electrically connected to individual lamp elements, the analog control circuit controlling the flashing rate of the lamp elements, the flashing rate being above a critical flicker fusion frequency of a viewer; wherein the light emitted by the individual lamp elements appears to a viewer to be a predominantly a secondary color when the lamp is stationary relative to the viewer; and wherein the colors emitted by the individual lamp elements are separately perceived by the viewer when the lamp is moved rapidly relative to the viewer.

30. The portable lighting device of claim 26, wherein the selectable control means includes a microprocessor functional to control one or more operation modes of the lamp.

31. The portable lighting device of claim 30, wherein said one or more lamp operation modes is selected from an on-off switched mode, a flashing mode, a brightening mode, a dimming mode, and an auto-off mode.

32. The portable lighting device of claim 31 , wherein the microprocessor further controls a cycle rate or intensity of the lamp within a selected operation mode.

33. The portable lighting device of claim 31, wherein the microprocessor controls a brightening or dimming mode having at least two selectable lamp intensity options, a flashing mode having at least two selectable lamp flashing rate options, and an auto-off mode functional to automatically terminate power to the lamp after a predetermined time of operation.

34. The portable lighting device of claim 1, further comprising an accessory piece.