WO2007012134A1

WO2007012134A1 - Electric cord connection housing unit

Info

Publication number: WO2007012134A1
Application number: PCT/AU2006/001060
Authority: WO
Inventors: Gerard Anthony Harrington
Original assignee: Gerard Anthony Harrington
Priority date: 2005-07-27
Filing date: 2006-07-27
Publication date: 2007-02-01

Abstract

An electric cord connection housing for secure encapsulation of a coupled plug pair, each plug connecting to a respective electric cord, the housing comprising first and second housing portions, and a latch for securing the housing portions to one another when the housing is in a closed configuration. The housing portions has respective complementary mating edges such that when the housing is in the closed configuration, the edges of the housing portions define at least two ports to receive the electric cords connected to respective plugs of the plug pair. The housing includes a continuous elongated first seal element extending around at least one of the respective mating edges and a pair of second seal elements each located in the region of their respective port. The first and second seal elements disposed in use in the closed configuration around a coupled plug pair, such that the seal elements substantially seal the mating edges against one another and seal the ports against the electric cords. The plugs of the coupled plug pair directly or indirectly abut the housing in the region of their respective ports such that the plug pair is secured against tensional forces which would cause the plug pair to be electrically uncoupled when the housing is in the closed configuration.

Description

Electric Cord Connection Housing Unit

Field of the invention

The present invention relates to the general field of electric cord connections and more particularly to an electric cord connection housing unit, suitable for use in securing the connection between power extension cords and power tools.

Background of the invention

In this specification where a document, act or item of knowledge is referred to or discussed, this reference or discussion is not an admission that the document, act or item of knowledge or any combination thereof was at the priority date publicly available, known to the public, part of the common general knowledge or known to be relevant to an attempt to solve any problem with which this specification is concerned.

Electric extension cords are commonly used in the transmission of power from a source to an electric device, in a range of environments including domestic, commercial and industrial environments. For example, in the household, extension cords are widely used in the operation of power tools, vacuum cleaners, mobile lighting appliances, and other portable electric equipment. It is not uncommon for a number of extension cords to be interconnected to enable the use of a device at a substantial distance from a power point. For example this type of arrangement may be used by people operating an electric lawn mower or hedge trimmer, or electric power tools on a building site.

Typically, an electric extension cord comprises a male and a female plug, connected by a length of flexible mains power cable. The male plug is connected to a mains power outlet, and the male plug of the electric appliance (or a further extension cord) can then be connected to the female plug of the extension cord. This connection between the male and female plugs is of concern, as it tends to be subject to lateral tension as the user moves around the work area.

This tension can often lead to separation of the male and female plugs and disconnection of the conducting elements in the plugs. This can be a considerable inconvenience because the user has to manually reconnect the plugs. This may involve lengthy downtime on the part of the operator, particularly if for example, they need to come down from a ladder or leave one work area for another.

More significantly, the problem raises serious safety issues, as partial separation can result in the exposure of the live conducting elements in the plugs. This is especially dangerous when an extension cord is used on building and construction sites where the environment can be harsh and cords can readily become separated. Problems also exist when an extension cord is used in wet environments, such as on damp grass, in wet weather or in wet areas such as kitchens and bathrooms because moisture can conduct electricity and cause an electrocution hazard.

There have been attempts in the past to address this problem, including the use of protection devices to shroud the plug interconnection. Some of these devices are described for example in US-6,036,526, US-6,099,340, US-5,755,588 and US-5,129,839. US- 5,129,839 for example comprises an elongate housing having a sliding bracket to immobilise the plug pair in the housing. Some of these devices have been effective in certain circumstances, but none has provided an adequate solution to the problem in a form suitable for use with the wide variety of plug designs currently available.

Summary of the invention

The present invention provides an electric cord connection housing for secure encapsulation of a coupled plug pair, each plug connecting to a respective electric cord, the housing comprising

(a) first and second housing portions,

(b) a latch for securing the housing portions to one another when the housing is in a closed configuration,

the housing portions having respective complementary mating edges such that when the housing is in the closed configuration, the edges of the housing portions define at least two ports to receive the electric cords connected to respective plugs of the plug pair,

wherein the housing includes a continuous elongated first seal element extending around at least one of the respective mating edges and a pair of second seal elements each located in the region of their respective port, the first and second seal elements being disposed such that, when in use in the closed configuration around a coupled plug pair, the seal elements substantially seal the mating edges against one another and seal the ports against the electric cords,

and wherein the plugs of the coupled plug pair directly or indirectly abut the housing in the region of their respective ports such that the plug pair is secured against tensional forces which would cause the plug pair to be electrically uncoupled when the housing is in the closed configuration.

Preferably the housing is adapted to accommodate a variety of plug shapes and sizes.

Typically, when the housing is in the closed configuration the plugs will abut the respective ends of the housing such that the plug pair fits snugly in the housing. If one of the plugs in the plug pair does not abut an end of the housing, a keeper can be inserted in the gap between a plug and the end of the housing to ensure the plugs are secured against lateral movement.

Typically the keeper consists of one or more generally C-shaped keeper rings which can be fitted around one or of the electric cords of the plug pair, such that the keeper abuts an end of the housing and the plug.

Although the housing typically has cord ports at opposed ends, these ports could instead by provided along the longitudinal sides of the housing.

Typically, in the closed configuration the housing is generally elongate and of cylindrical cross-section. The mid-section of the housing may have a generally greater cross section than the ends of the closed housing adjacent the cord ports.

Preferably, the housing portions are produced from the same mold or cast. Typically the two housing portions are interconnected by means of at least one integral hinge element. For example the hinge may be provided at one side of the respective housing portions and the one or more latches provided at the other side.

In a particularly preferred embodiment the housing portions, the hinge and one or more latches are formed integrally, for example from a single mould or cast.

Preferably the first seal element is a continuous elongated seal element extending around the mating edge of the second housing portion. An elongate lip may be provided adjacent the edge of one the housing portions to overlap the edge of the other housing portion when the housing is in the closed configuration. In a preferred embodiment each of the second seal elements is sufficiently compressible to accommodate a variety of cord diameters, yet still provide resistance to water or moisture ingress. Typically, when the housing is in the closed configuration each second seal consists of one or more rings of generally frustro-conical shape. The second seals are preferably significantly thicker than the elongated seal element extending around the mating edge of the housing portion.

Each second seal element is typically retained adjacent a port by a shoulder or flange projecting inwardly from the interior wall of the housing.

The housing unit may include a keeper leash configured for attachment to an electric cord to retain the unit when not in use.

The housing may also be adapted for attachment of one or more straps for hanging up the housing when not in use, or alternatively, hanging in a convenient place during use. It may be convenient for example, to hang the housing on a workman's utility belt.

Brief description of the drawings

One embodiment of the present invention will now be described with reference to the following non-limiting example and with reference to the accompanying drawings, in which:

Figure 1 shows in isometric view an electric cord connection housing in its open configuration 10 in accordance with the present invention;

Figure 2 shows the unit of Fig. 1 in side elevation in its closed configuration;

Figure 3 shows a transverse cross-section of the housing at I-I of Figure 2;

Figure 4 shows a longitudinal cross-section of one embodiment of the end of the housing; and

Figure 5 shows a keeper ring according to one embodiment of the invention.

Detailed description of the drawings

A conventional electrical extension cord connection comprises flexible electric conductor cords 20,20', respectively terminating in a female and a male plug 21,22. The plug configuration can take a variety of different forms and sizes, as standard electric plugs vary from country to country. Even within a single jurisdiction a range of different designs are commonly available.

As described above, the coupling between plugs 21 and 22 can put under tension such that the coupling becomes unreliable thus leading to substantial safety risks.

Cord connection housing 10 generally comprises a smooth, contoured one-piece plastic housing designed to surround interconnected plugs 21,22 to maintain the interconnection and provide protection to the coupled assembly, as will be explained in more detail below. The smooth contoured shaping of unit 10 enables the device when clamped in place to be dragged around on the extension cord without catching or snagging on obstructions.

Two housing portions 1 1 and 12 make up unit 10, interlinked by means of an integral seam- type hinge element 13 (Fig. 2). Each housing portion 11,12 has a generally longitudinal dished form, with a wide mid-portion of generally hemi-cylindrical section, tapering towards two end parts also of generally hemi-cylindrical shape as illustrated in Figs.l and 2. In its closed configuration, housing 10 forms an axially-bisected, generally cylindrically shaped plastic capsule, tapering towards the ends. Housing 10 may be formed from an injection-moulded plastic material, preferably of somewhat flexible and resilient properties, such as polypropylene, polyethylene, or a mixture of the two.

Housing portions 11 and 12 are provided with substantially planar peripheral mating faces as shown which come together to close the unit when in use. Housing portions 11,12 also have respective complementary integrally moulded latch elements 14,14' each located on the side opposed the hinge element 13, to secure together the two housing portions of unit 10 when it is closed over interconnected plugs 21,22. The end part of each housing portion 11,12 terminates in a semicircular opening as shown. When the housing is in its closed configuration these opening form circular ports through which the cords 20,20' pass.

A primary moisture seal is provided by a bead or ring 17 of soft, compressible silicone plastic or rubber, running around the entire internal periphery of the mating faces of the two housing portions 11 and 12. Primary seal 17 is bonded within a groove formed in the mating faces of the housing portions. At the semi-circular ends of housing portions 11 and 12, adjacent the ports, the primary seal is bonded to the thick secondary seals 18', 18".

In this way, when the housing is closed, the opposed portions of seal 17 press against one another around the planar mating faces to provide a moisture seal, whilst each arcuate end section of seal 17 provides half of an annular moisture seal around the outer insulation of cords 20,20', the flexible mounting elements 18 allowing the accommodation of electrical cords of varying diameters without compromising the integrity of the seal. This arrangement provides waterproofing capability at all critical points for potential moisture ingress.

The housing also includes a longitudinal lip is projecting from the outer edge of the planar mating face of one of the housing portions 12 to overlap the other portions 11 when the unit is closed, to provide a dirt seal along the length of the housing when in use.

Additionally, both the secondary seals 18/18' and 18"/18'" at respective ends of each housing portion 11,12 are retained adjacent their respective ports by a semi-circular, interiorly projecting flange 30, 30', 30", 30'" to seal the circular ports against the cords.

As Fig. 4 shows, the tapered end parts of the housing portions have a hemi-cylindrical internal shaping. In this embodiment, the second seal 18, 18' is of frustro-conical shape and retained in position adjacent the port by flanges 30, 30' projecting from the inner walls of the respective housing portions 11, 12. These flanges 18, 18' are of flexible plastic or rubber and when unit 10 is closed they serve to engage at their tips the outer insulation of cord 20. Preferably, in use the plugs abut the end of the housing at, or adjacent the flanges so that if the cords experience lateral force or tension the plugs will not separate. If the plugs do not abut the end of the housing or the second seal, C-shaped keeper rings of the configuration depicted in Figure 5 can be located around the cord 2% in the space 16 and thus abuts the plug and the flange 30,30'.

The sectional view in Fig. 3 illustrates a secondary seal 18, 18' engaging the outer insulation of cord 20. The copper conductors within cord 20 are depicted by reference 23.

In use, housing 10 is opened by means of latch 14, 14' and the interconnecting plugs, and optionally, the keeper rings are place in one of the housing portions. The two cords are respectively routed via the tapering sections through the second seals and the ports, and the housing is then closed and latched.

The device of the preferred embodiment of the invention, then, provides a convenient, one- piece unit which, in use, encapsulates the interconnected plug assembly in a physically robust manner, providing a high degree of water resistance." This prevents potentially dangerous exposure of live tines, maintains the connected plugs together, and serves to transfer any load on the cords directly to the housing itself, rather than to the plugs. In addition to the safety advantages, the unit provides a time saving capability, by eliminating the need to reconnect accidentally disconnected electrical leads. Modifications and improvements to the invention, whether in terms of additional or alternative features, will be readily apparent to those skilled in the art.

Those skilled in the art will appreciate that the device as described is susceptible to various further changes and modifications without departing from the spirit and scope of the invention.

Claims

C l a i m s

1 The present invention provides an electric cord connection housing for secure encapsulation of a coupled plug pair, each plug connecting to a respective electric cord, the housing comprising

(a) first and second housing portions,

wherein the housing includes a continuous elongated first seal element extending around at least one of the respective mating edges and a pair of second seal elements each located in the region of their respective port,

the first and second seal elements being disposed such that, when in use in the closed configuration around a coupled plug pair, the seal elements substantially seal the mating edges against one another and seal the ports against the electric cords,

2. Preferably the housing is adapted to accommodate a variety of plug shapes and sizes.

3. Typically, when the housing is in the closed configuration the plugs will abut the respective ends of the housing such that the plug pair fits snugly in the housing. If one of the plugs in the plug pair does not abut an end of the housing, a keeper can be inserted in the gap between a plug and the end of the housing to ensure the plugs are secured against lateral movement. 4 Typically the keeper consists of one or more generally C-shaped keeper rings which can be fitted around one or of the electric cords of the plug pair, such that the keeper abuts an end of the housing and the plug.

5 Although the housing typically has cord ports at opposed ends, these ports could instead by provided along the longitudinal sides of the housing.

6 Typically, in the closed configuration the housing is generally elongate and of cylindrical cross-section. The mid-section of the housing may have a generally greater cross section than the ends of the closed housing adjacent the cord ports.

7 Preferably, the housing portions are produced from the same mold or cast. Typically the two housing portions are interconnected by means of at least one integral hinge element. For example the hinge may be provided at one side of the respective housing portions and the one or more latches provided at the other side.

8 In a particularly preferred embodiment the housing portions, the hinge and one or more latches are formed integrally, for example from a single mould or cast.

9 Preferably the first seal element is a continuous elongated seal element extending around the mating edge of the second housing portion. An elongate lip may be provided adjacent the edge of one the housing portions to overlap the edge of the other housing portion when the housing is in the closed configuration.

10 In a preferred embodiment each of the second seal elements is sufficiently compressible to accommodate a variety of cord diameters, yet still provide resistance to water or moisture ingress. Typically, when the housing is in the closed configuration each second seal consists of one or more rings of generally frusto- conical shape. The second seals are preferably significantly thicker than the elongated seal element extending around the mating edge of the housing portion.

11 Each second seal element is typically retained adjacent a port by a shoulder or flange projecting inwardly from the interior wall of the housing.

12 The housing unit may include a keeper leash configured for attachment to an electric cord to retain the unit when not in use. 13 The housing may also be adapted for attachment of one or more straps for hanging up the housing when not in use, or alternatively, hanging in a convenient place during use. It may be convenient for example, to hang the housing on a workman's utility belt.