US3585544A - Switch having magnetic latching means - Google Patents

Abstract

A rotary switch with separable stationary and movable contacts and having a shaft which is rotatable to actuate the movement of the movable contacts between first and second operating positions. A spring return mechanism biases the shaft toward a first angular position corresponding to the first operating position of the movable contacts. A lever arm is mounted on the shaft for movement therewith and carries a magnetic armature. A stationary magnetic structure is disposed adjacent to the shaft and includes a permanent magnet member. When the shaft is rotated to a second angular position which corresponds to the second operating position, the magnetic armature engages or seats against the stationary magnetic structure and the magnetic flux from the permanent magnet member passes through the armature to magnetically latch the shaft in the second angular position against the influence of the spring return mechanism. An electromagnetic coil or winding is disposed on the stationary magnetic structure and is energizable to provide a magnetic flux which opposes the magnetic flux which passes through the armature from the permanent magnet member to thereby release the armature and the shaft which is then actuated to the first angular position by the spring return mechanism.

Description

United States Patent [72] Inventors Charles M. Cleaveland Monroeville; Wesley L. McKeithan, Pittsburgh, both of, Pa. [21] Appl. No. 862,427 [22] Filed Sept. 30, 1969 [45] Patented June 15, 1971 [73] Assignee Westinghouse Electric Corporation Pittsburgh, Pa.

[54] SWITCH HAVING MAGNETIC LATCIIING MEANS 9 Claims, 15 Drawing Figs.

[52] U.S.CI H 335/170, 200/11 [51] Int.Cl.... 1101b 9/20 [50] 335/114, 170,174, 253, 254,136,125, 77, 200/11,1lA

[56] References Cited UNITED STATES PATENTS 3,109,906 11/1963 Abendroth 335/170 3,206,564 9/1965 Hauser 200/11 (A) 3,229,052 1/1966 Si1vius.... 200/11 (A) 3,253,098 5/1966 Perry 335/170 3,444,490 5/1969 KrummeL... 335/170 Primary [:xammen-Harold Broome Attorneys--A T Stratton and Clement L McHale ABSTRACT: A rotary switch with separable stationary and movable contacts and having a shaft which is rotatable to actuate the movement of the movable contacts between first and second operating positions A spring return mechanism biases the shaft toward a first angular position corresponding to the first operating position of the movable contacts. A lever arm is mounted on the shaft for movement therewith and carries a magnetic armature. A stationary magnetic structure is disposed adjacent to the shaft and includes a permanent magnet member. When the shaft is rotated to a second angular position which corresponds to the second operating position, the magnetic armature engages or seats against the stationary magnetic structure and the magnetic flux from the permanent magnet member passes through the armature to magnetically latch the shaft in the second angular position against the influence of the spring return mechanism. An electromagnetic coil or winding is disposed on the stationary magnetic structure and is energizable to provide a magnetic flux which opposes the magnetic flux which passes through the armature from the permanent magnet member to thereby release the armature and the shaft which is then actuated to the first angular position by the spring return mechanism.

PATENTED JUN] 5:971

SHEET 1 [IF 2 FIGB.

aso INVENTORS WITNESSES Charles M. Cleovelond 0nd Wesley L, McKeithon ATTORNEY SWITCH HAVING MAGNETIC LATCHINGMEANS BACKGROUND OF THE INVENTION This invention relates to rotary control switches and more particularly to means for remotely operating such switches.

In certain types of electrical apparatus such as rotary switches of the type disclosed in U.S'. Pat. Nos. 3,206,564; 3,229,051; and 3,229,052 which are all assigned to the same assignee as the present application, it is sometimes necessary or desirable to provide for operation of the switches from a point or location which is remote from the switches. For example,'in a particular application, simultaneous operation of a plurality of rotary switches may be required to actuate the simultaneous tripping of a plurality of associated circuit breakers. In known switches of this type, one means for remote operation of such switches which has been employed is to mechanically latch each switch in a particular operating condition and to employ an electrical solenoid which is energized to actuate the release of the mechanical latch for remote operation of the associated switch. Such known switch structures have certain disadvantages with respect to either the overall'size andweight of the switch structure or with respect to the speed of operation of the switch when operated from a point which is remote from the switch.

SUMMARY OF THE INVENTION In accordance. with the invention, a rotary switch comprises separable stationary and movable contacts whose operation between first and second operating positions is actuated by the rotation of an associated shaft between corresponding first and second angular positions, respectively. A biasing means which may be of the spring return type, is provided to bias the shaft to the first of the angular operating positions of said shaft. A lever arm having a magnetic armature thereon is mounted on the shaft for rotation therewith. A stationary magnetic structure is disposed adjacent to the shaft and includes a permanent magnet member. When the shaft is manually actuated to the second angular position by suitable means such as a handle, the armature engages the stationary magnetic structure and the magnetic flux from the permanent magnetic member passes through the armature to magnetically latch the shaft in the second angular position against the influence or force of the associated biasing means. In order to release the armature, an electromagnetic means, such as an energizable winding, is disposed on the stationary magnetic structure to provide a magnetic flux which opposes the magnetic flux which passes through the armature from the permanent magnet member thereby reducing the holding or latching force of the stationary magnetic structure. When the armature is released, the shaft is actuated to the first angular position of said shaft by the biasing means.

In an illustrated embodiment of the invention, a second shaft having a handle mounted thereon may be provided which is coupled to the shaft which actuates the operation of the overall switch contacts by a coupling means which couples the shafts together for rotation in a direction toward the second angular position of the shaft. This coupling means provides a predetermined amount of rotary lost motion between the shafts when the second shaft is rotated in a direction away from the second angular position of the other shaft to thereby restrict or limit control of the switch to remote operation when the other shaft is magnetically latched in the second angular position.

It is therefore an object of this invention to provide a new and improved means for remotely operating a rotary switch structure.

BRIEF DESCRIPTION OF THE DRAWING Other objects of the invention will be apparent from the following detailed description taken in conjunction with the accompanying drawings, in which:

FIG. Us a view, partly in side elevation and partly in section, of a rotary switch structure embodying the invention;

FIG. 2 is a view, in section, taken along the line II-II of FIG.

FIG. 3 is a view, in section, taken along the line III-III of FIG. 1;

FIG. 4 is a view, in section, taken along the line I\ /-IV of FIG. 1, with certain parts broken away;

FIG. 5 'is an enlarged diagrammatic view of a magnetic structure which forms part of the switch structure shown in FIG. I;

FIG. 6 is an enlarged detail view showing a portion of the rotary switch of FIG. I;

FIG. 7 is a view, in section, taken along the line VII-VII of 7 FIG. 6;

FIGS. 8 and 9 are sectional views similar to FIG. 7 illustrating the parts shown in FIG. 7 in other operating positions;

FIG. 10 is an enlarged detailed view showing a modified portion of the rotary switch of FIG. 1;

FIG. 11 is a view, in section, taken along the line XI-Xl of FIG. 10; 4

FIGS. I2 and 13 are sectional views similar to FIG. 11 illustrating the positions of the parts in other operating positions;

FIG. 14 is a schematic diagram illustrating the electrical connections of certain portions of the rotary switch shown in FIG. I in a particular application; and

FIG. 15 is an enlarged detailed view showing a modified portion of the rotary switch of FIG. 1;

DESCRIPTION ()F THE PREFERRED EMBODIMENTS Referring now to the drawings and FIG. 1 in particular, the switch structure shown therein comprises a dial plate assembly 222, a first housing 210 for a magnetic latching means 30, a mechanism housing 153, a first stage stator housing 23, a second stage stator housing 25, and the spacing members 27 which are disposed at the opposite ends of the stator housings 23 and 25 and which may be disposed between successive stator housings where a plurality of stator housings are provided as disclosed in greater detail in US. Pat. No. 3,206,564 and the other patents previously mentioned for a switch structure of the same general type as shown in FIG. 1. A first shaft 26 extends axially through most of the switch structure and is rotatably disposed in bearings (not shown) which may be provided at one end of the switch structure and at a location near the other end of the switch structure. A second shaft 126 projects axially to the left of the dial plate assembly 222 and extends axially into the housing 210 with the second shaft 126 being coupled to the first shaft 26 by a coupling means which includes the bushing 122 for rotation with the first shaft 26 during certain operating conditions, as will be described hereinafter. A handle 28 is removably attached or secured to the left end of the second shaft 126 by a screw 29 and an end cover (not shown) may be removably attached at the other end of the switch structure opposite the handle 28. A rotor assembly 20 and a cam 73 may be carried by the first shaft 26 and where provided are rotatable with the shaft 26.

The switch structure shown in FIG. 1 may be mounted on a switchboard panel 33 or other supporting structure by means of the screws 162 which extend through the dial plate assembly 222 and the first housing 210 and into the mechanism housing 153 which is disposed on the opposite side of the panel 33 from the dial plate assembly 222. The heads of the screw 162 are covered by the dial plate cover 22 which is snapped over the dial plate assembly 222.

The stator housings 23 and 25 may be retained in axial alignment on the switch structure by means of the bolts 183 which extend axially from the mechanism housing 153 through the stator housings 23 and 25 and any additional stator housings where provided, as explained in detail in the patents previously mentioned. The stator housings 23 and 25, the spacing members 27, the rotor 63 of the rotor assembly 20 and the cam 73 are preferably molded from an electrically insulating material having excellent nontracking arc and wear resistant characteristics, such as a glass-polyester material with an aluminum trihydrate filler. Thus each of the parts of the switch structure which are subject to wear has a relatively long life.

As indicated-in FIG. 1, a plurality of pairs of stationary contact members 47 may be disposed in two rows around the periphery of the first stator housing or contact support member 23. The respective pairs of contact members 47 are angularly or circumferentially spaced at predetermined angles around the periphery of the switch structure. The two contact members of each pair are spaced axially with respect-to the stator housing 23. Each contact member 47 functions as a terminal 'member and as a contact member. Each contact member 47 is composed of a suitable electrically conducting material and may have a head which is enlarged in one plane to engage the walls of a recess in the stator housing 23, as

described in detail in the patents previously mentioned. The

head of each contact member 47 may be beveled and is engaged by a contact roller carried by the rotor assembly 20, as will be described more fully hereinafter. Each contact member 47 is retained in the stator housing 23 by means of a nut 49 which isthreaded onto the contact member 47 to engage a washer, as shown in FIG. 1. The number of pairs of contact .members 47 and their relative positions may be varied as required in a particular application, as disclosed in detail in the patents previously mentioned.

The rotor assembly may have one or more contact rollers 61 disposed at predetermined angular positions around the periphery of the rotor assembly 20 as required in a particular application. The rotor assembly 20 may be of a one-piece construction and comprises a hub 63 and a plurality of arms which are formed integrally with the hub 63, as described in detail in the patents previously mentioned. Each contact roller 61 is composed of a suitable electrically conducting material and is provided with two spaced, integrally formed enlarged contact portions 65. Each contact roller 61 is disposed in a slot provided in one of the arms of the rotor assembly 20 and is biased radially outwardly in the rotor assembly 20 by an associated spring with aspn'ng seat 67 being disposed between one end of each'of the contact rollers 61 and the associated spring. In

order to reduce the friction between the contact portions 65 of each contact roler 61 and the heads of the stationary contact member 47,'each contact roller61 is rotatably mounted in one of the arms of the rotor assembly 20 and in order to further reduce such friction, a wheel 69 which is composed of electrically insulating material may be rotatably mounted on each end of each of, the contact rotors 61 outside of the adjacent enlarged contact portion 69, as described in detail in the patents previously mentioned. In order that the rotor assembly 20 rotate with the shaft 26, the hub 63 of the rotor assembly 20 has a square opening for receiving the shaft 26 and the portion of the shaft 26 on which the rotor assembly 20 is carried has a similar cross section.

In certain applications, it is desirable to provide a switch structure having normally closed contact members. The second stator housing or contact support member 25 shown in FIG. 1 has such normally closed contact members mounted thereon. As indicated in FIG. 1, a plurality of pairs of axially spaced contact members 57 may be angularly or circumferentially spaced around the periphery of the stator housing 25 with the inner ends 77 of each pair of contact members 57 extending axially toward each other. A bridging contact member 71 is biased into engagement with the ends 77 of the associated contact members 57 by an associated spring as described in detail in the patents previously mentioned. The bridging contact member 71 is disengaged from the ends 77 of the contact members 57 when a roller 75 on the bridging contact member 71 is engaged by the cam 73 with the movement of the contact bridging member 71 being guided by a contact guide 79 which is disposed between the contact members 57 of each pair of contact members. The cam 73 also includes a hub portion having a square opening for receiving shaft 26 with the portion of the shaft 26 which carries the cam 73 having a similar cross section in order that the cam 73 rotates with the shaft 26. I

In order to return or bias the shaft 26 to a normal or off? angular operating position as indicated at 228' in FIG. 8 which corresponds to a first operating position of the movable contact rollers 65 and the bridging contact members 71, where provided, when the shaft 26 is released from the influence of the magnetic latching means 30, as will be described more fully hereinafter, a spring return assembly or mechanism 50 is provided in the housing 153. As best shown in FIGS. 1 and 4, a doubly wound spring 152 is disposed on a bushing 137 which rotates with the shaft 26. The bushing 137 is provided with the projections or ears 137A and 1378 which engage the ends of the spring 152 and the ends of the spring 152 engage the projections or stops 143 and 145 in the mechanism housing 153 to return the shaft 26 to its normal or "off" angular operating position when the shaft 26 is released. In order to reduce the friction between the spring 152 and the bushing 137, a generally tubular bushing 136 which is formed from a material having a relatively low coefficient of friction such as 0.17 is disposed on the bushing 137 between the turns of the spring 152 and the outer surface of the bushing 137. It is to be noted that the housing 153 may be closed off at the front end thereof by means of a cover plate 155 having an opening through which the shaft 26 passes as shown in FIG. 1.

In order to magnetically latch the shaft 26 in a second angular operating position or on" position which corresponds to a second operating position of the movable contact rollers 61 and the bridging contact members 71, where provided, a releasable magnetic latching means or mechanism 30 is disposed in the first housing 210, as shown in FIG. 1. It is to be noted that the housing 210 may be secured to the mechanism housing 153 by suitable means, such as a plurality of screws 165, which pass through openings provided in the front of the housing 210 and in a rear cover plate 212 and that a gasket 211 may be provided between the front portion of the housing 210 and the rear cover plate 212 to prevent the entrance of dust or other contaminating materials into the housing 210.

More specifically, the magnetic latching means 30 as shown in FIGS. 1 and 3 includes a lever arm 220 which is mounted on the shaft 26 for rotation therewith. The upper end of the lever arm 220 has a square opening which is adapted to receive a portion of the shaft 26 having a similar cross section or shape. In order to axially position the lever arm 220 on the shaft 26, the generally tubular spacer member 129 is disposed on the shaft 26 between the lever arm 220 and the rear cover 212 of the housing 210. A magnetic armature or movable keeper member 230 is loosely mounted or supported at the outer end of the lever arm 220 by suitable means, such as the screw 232.

The magnetic latching means 30 also includes a stationary magnetic structure 300, as shown in FIGS. 3 and 5. As shown in FIG. 5, the stationary magnetic structure 300 comprises a pair of spaced upper and lower plates 313 and 315, respectively, which are formed from a suitable soft magnetic material, such as steel or iron. It is to be noted that the right ends of the plates 313 and 315 form the pole faces 316 and 318, respectively, against which the armature 230 seats or engages when the lever arm 220 is magnetically latched by the magnetic latching means 30, as will be described more fully hereinafter. In order to provide the magnetic flux which passes through the armature 230 and magnetically latches the armature 230 against the stationary magnetic structure 300 as shown in FIG. 5, a permanent magnet member 350 is provided which extends traversely between the plates 313 and 315, as shown in FIG. 5. In order to provide an alternate path having a relatively low magnetic reluctance for the magnetic flux from the permanent magnet member 350 to thereby prevent demagnetization of the permanent magnet member 350 and to reduce the amount of magnetic fiux provided by the coil 320 which is required to release the armature 230, the stationary magnetic structure 300 also includes a magnetic plate member or fixed keeper 312 which is disposed adjacent to the left ends of the plates 313 and 315 and which is also formed from a suitable magnetic material, such as steel or iron. It is to be noted that the fixed keeper 312 is spaced from the adjacent ends of the plates 313 and 315 by a spacer member 314 which is formed from a nonmagnetic material and which establishes a predetermined nonmagnetic gap in the altemate, low reluctance path which includes the fixed keeper 312.

In order to actuate the release of the armature 230 and, in turn, the shaft 26 when the armature 230 is magnetically latched to the stationary magnetic structure 300 as shown in FIGS. 3 and 5, the energizing or operating coil or winding 320 is disposed on one of the magnetic plates 313 or 315. The

operating coil or winding 320 may include a plurality of conductor turns which are disposed to surround the upper mag-.

netic plate 313 as illustrated. When a voltage is applied to the operating coil or winding 320 and current flows in the conductor turns of the operating coil or winding, the magnetic flux which is produced will be in such a direction as to pass through the armature 230 and to oppose the magnetic flux from the permanent magnet member 350 which passes through the armature 230. The effective reluctance of the magnetic path which includes the armature 230 will be thus increased and the magnetic flux from the permanent magnet member 350 will then shift or transfer to the relatively lower reluctance magnetic path which includes the fixed keeper312 to thereby release the armature 230 and the associated shaft 26. It is to be noted that the various parts which form the stationary magnetic structure 300 as just described may be encapsulated or embedded in a suitable thermosetting material,

such as an epoxy resin, or a thermoplastic resin and that the stationary magnetic structure 300 may be secured to the rear cover 212 of the housing 210 by suitable means, such'as a plurality of rivets 161, which pass through the stationary magnetic structure 300 and secure the stationary magnetic structure 300 to the rear cover 212 of the housing 210.

As previously mentioned, the shaft 126 on which the handle 28 is mounted is operatively connected or coupled to the shaft 26 during certain operating conditions by a coupling means which comprises the generally tubular bushing member 122, as best shown in-FIGS. 1, 6 and 7. More specifically, the bushing 122 is secured to the shaft 126 for rotation therewith by a cross pin 123 which passes through aligned openings in the bushing 122 and the shaft 126. The bushing 122 also includes a portion 122A of reduced size which projects through an opening in the front portion of the housing 210 to assist in rotatably supporting the shaft 126. The cross pin 123 may also include a portion which projects beyond the outer surface of the bushing 12.! and which is adapted to engage a stop member 223 which is formed, as illustrated, integrally with the front portion of the housing 210, as best shown in FIGS. 1,2 and 3. The bushing 122 also assists in axially positioning the lever arm 220 on the shaft 26 since the right end of the bushing 122 as viewed in FIG. 1 projects over the adjacent end of the shaft 26 with the lever arm 220 being disposed between the housing 122 and the spacer member 129. The shaft 126 also includes a portion 126A of reduced cross section which projects axially into a recess 26A which is provided at the left end of the shaft 26 as viewed in FIG. 1 to assist in rotatably supporting the shaft 126.

In order to provide a predetermined amount of rotary lost motion between the shafts 126 and 26 when the handle 28 and the shaft 126 are rotated in a direction that would rotate the shaft 26 and the associated lever arm 220 in a counterclockwise direction, as viewed in FIG. 3 and that would otherwise move the armature 230 away from the latched position shown in FIGS. 3 and 5, the bushing 122 includes a plurality of generally arcuate recesses 122C as best shown in FIG. 7. As shown in FIG. 7, the generally arcuate recesses 122C of the bushing 122 are disposed adjacent to the corners of the square shaft 26 so that when the handle 28 and the associated shaft 126 along with the bushing 122 are rotated in a counterclockwise direction, as viewed in FIG. 7, the bushing 122 will rotate in a counterclockwise direction to the position shown in predetermined amount of rotary lost motion is provided between the shafts 126 and 26 when the shaft 126 is rotated in t a counterclockwise direction from the position shown in FIG. 7, which corresponds to the position of the shaft 126 in FIG. 1, to the position shown in FIG. 8 to thereby prevent the manual release of the lever arm 220 under the influence of the force exerted on the handle 28 and the associated shaft 126. In order to prevent the shaft 126 from being rotated in a counterclockwise direction beyondthe limits of the predetermined amount of rotary lost motion indicated in FIGS. 7 and 8, the cross pin 123 is extended radially as shown in FIG. 3 andengages the stop member 223 on the housing 210 to prevent the shafts 126 and 26 in a counterclockwise direction to thereby prevent manual overriding of the magnetic latch and also prevent the shaft 26 from being manually turned to the off" position of the contacts.

On the other hand, if the shaft 126 is rotated manually by means of the handle 128 in a clockwise direction, the internal configuration or shape of the bushing 122, as shown in FIG. 7, is such as to cause the shaft 26 to rotate with the shaft 126' in a direction to actuate the lever arm 220 and the armature 230 toward the latched position shown in FIG. 3 from the normal or off" position of the shaft 26 which is indicated by the dotdash line 228' in FIG. 3.

In order to apply a unidirectional voltage to the operating coil or winding 320 of the stationary magnetic structure 300, as shown schematically in FIG. 14, a source of alternating current voltage as indicated at S1 may be electrically connected to the operating coil 320 through the contact 410 of the relay 400 which actuates the remote operation of the switching structure shown in FIG. 1, the closed contact rollers 61 of the switch structure previously described, the terminals of a terminal block indicated diagrammatically at 360 in FIG. 14, and through the full wave rectifier 340, which is indicated in block form in FIG. 14. The rectifier 340 may be omitted with an alternating current supply if maximum speed of the switching operation is not necessary. In other words, the coil 320 will function properly when energized with either direct current or alternating current power. Minimum operating time is assured by direct current since alternating current may produce magnetic flux during the half-cycle which is in a direction to aid the flux from the permanent magnet member 350 rather than oppose it.

In order that the position of the handle 28 reflect the actual operating condition of the switch structure shown in FIG. 1, a pair of biasing leaf springs 255 are disposed to engage the shaft 126, as best shown in FIG. 2. The bent ends of the leaf springs 255 are disposed in the arcuate recesses provided in .the dial plate 222, as indicated at 222A and 2228. When the handle 28 and the associated shaft 126 are rotated in a counterclockwise direction while the switch structure is magnetically latched by the magnetic latching means 30 previously described, the handle 28 and the shaft-126, along with the bushing 122, may rotate in a counterclockwise direction to the positions indicated in FIG. 8 without unlatching the armature 230 and the shaft 26, as just explained. When the handle 28 is then released, the leaf springs 255 will actuate the handle 28 to the position indicated in phantom at 228 in FIG. 2 in order that the handle 28 reflect the actual operating condition or position of the switch structure shown in FIG. 1. When the shaft 26 is released bythe energization of the operating coil or winding 320, the bushing 122 and the shaft 26 will be actuated from the position shown in FIG. 7 which corresponds to the magnetically latched condition of the switch structure shown in FIG. 1 in a counterclockwise direction to the position shown in FIG. 9 due to the internal configuration of the bushing 122, as indicated in FIGS. 7 and 9, and the handle 28, along with the shaft 126, will be actuated in a counterclockwise direction against the influence exerted on the shaft 126 by the biasing springs 255 since the spring return mechanism which includes the spring 152 is relatively stronger than the leaf springs 255.

In the overall operation of the switch structure shown in FIG. 1, it will be assumed first that the switch structure is in the off" or normal condition which corresponds to the first angular position of the shaft shown in FIG. 9 and which is indicated by the dot-dash line 228' in FIG. 3. In this operating condition, the armature 230 and the lever arm 220 are spaced away from the associated stationary magnetic structure, as indicated by the dot-dash line 228' in FIG. 3. In order to actuate the armature 230 to the magnetically latched position shown in FIG. 3, the handle 28 and the associated shaft 126, along with the bushing 122, are rotated in a clockwise direction, as viewed in FIG. 9, and due to the internal configuration of the bushing 122 as indicated in FIGS. 7 through 9, the shaft 26 will rotate with the shaft 126 until the shaft 26 reaches the second angular position shown in FIG. 7 and the armature 230, as well as the lever arm 220, reach the operating positions shown in FIG. 3 with the magnetic flux from the permanent magnet member 350 passing through the armature 230 which engages the pole faces 316 and 318 of the stationary magnetic structure 300, as previously described. It is to be noted that in this operating condition of the switch structure, the reluctance of the magnetic path which includes the armature 230 is relatively lower than that of the magnetic path which includes the fixed keeper 312 due to the presence of the nonmagnetic spacer member 314 and that most of the magnetic flux from the permanent magnet member 350 will therefore pass through the armature 230 to magnetically latch the armature 230 to the stationary magnetic structure 300.

Assuming that the armature 230 is in the magnetically latched position shown in FIGS. 3 and 5 and that the shaft 26 is in the "on" operating position indicated at 228 in FIG. 7, if the handle 28 and the shaft 126, as well as the bushing 122, are rotated in a counterclockwise direction from the operating positions shown in FIGS. 3 and 7, the predetermined amount of rotary lost motion between the shafts 126 and 26 will permit the bushing'122 to rotate to the position shown in FIG. 8 without unlatching the armature 230. This is due to the predetermined amount of rotary lost motion which is provided between the shafts 126 and 26, as previously described.

Assuming that the switch structure shown in FIG. 1 is in the magnetically latched condition and that the shaft 26 is in the position shown in FIG. 7, the switch structure shown in FIG. 1 may be remotely operated by energizing the operating coil or winding 320 of the stationary magnetic structure 300 shown in FIG. 5 by energizing said operating coil from a source of alternating current, as indicated at S1 in FIG. 14, through the full wave rectifier 340, as indicated in FIG. 14, by the closing of a contact 410 of a suitable control relay, as indicated at 400 in FIG. 14, or from a source of direct current if provided. It is to be noted that prior to the energization of the operating coil 320, the force exerted on the shaft 26 by the magnetic latching means 30 through the lever arm 220 is relatively greater than the force exerted on the shaft 26 by the spring return mechanism 50. When the operating coil 320 of the stationary magnetic structure 300 is energized, the magnetic flux from the operating coil 320 will pass through the armature 230 in such a direction as to oppose the magnetic flux from the permanent magnet member 350 to thereby release the armature 230 and the shaft 26 which will then move in a counterclockwise direction from the position shown in FIG. 7 to the position shown in FIG. 9 which corresponds to the second operating position of the switch structure shown in FIG. I. When the shaft 26 is actuated from the position shown in FIG. 7 to the position shown in FIG. 9 under the influence of the spring return mechanism 50 which includes the spring 152, the contacts 61 indicated diagrammatically in FIG. 14 will be actuated to the open position to thereby deenergize the operating coil or winding 320 of the stationary magnetic structure 300, so that it is not necessary to have a continuous current flowing in the winding 320.

It is to be noted that in the overall operation of the switch structure shown in FIG. 1 as just described, the loose mounting of the armature 230 on the lever arm 220 facilitates the alignment of the armature 230, the seating of the armature 230 on the pole faces 316 and 318 of the stationary magnetic structure 300 when the lever arm 220 is actuated to the magnetically latched position shown in FIG. 3.

Referring now to FIGS. 10 through 13, there is illustrated a second embodiment of the invention which comprises a switch structure as previously described except that the shape of the shaft 26 is modified to a shape as indicated by the shaft 326 in FIGS. 11 through 13 and the construction of the bushing 122 is modified to a shape as indicated by the bushing 322 in FIGS. 11 through 13. More specifically, the bushing 322 as indicated in FIGS. 11 through 13 is secured to the shaft 126 and includes a square openingas indicated at 322A. The shaft 326 which corresponds to the shaft 26 of the switch structure previously described is generally square except that the corners of the shaft 326 are ground off as indicated in FIGS. 11 through 13.

The overall operation of the switch embodiment indicated in FIGS. 10 through 13, is the same as the operation of the switch structure previously described. Briefly, when the handle of the switch which is mounted on the shaft 126 is rotated in a counterclockwise direction from the position indicated in FIG. 11 when the switch structure is in the magnetically latched position which corresponds to the angular operating position of the shaft 326 shown in FIG. 11, the bushing 322 will rotate in a counterclockwise direction to the position shown in FIG. 12. The construction of the shaft 326 and the bushing will provide a predetermined amount of rotary lost motion between the shafts 126 and 326 similar to the construction shown in FIGS. 6 through 9. In other words, when the switch structure of the second embodiment is in the magnetically latched condition indicated by the angular position of the shaft 326 in FIG. 11 and the handle on the shaft 126 is rotated in the counterclockwise direction along with the bushing 322, the bushing 322 will rotate in a counterclockwise direction to the position indicated in FIG. 12 without actuating the release of the magnetic armature on the shaft 326, as indicated in FIGS. 11 and 12. When the handle on the shaft 126 is actuated in the counterclockwise direction along with the bushing 322 from the position indicated in FIG. 11 to the position 12 and is then released, the handle on the shaft 126 will be returned to the position indicated at 228, FIG. 11 by the biasing leaf springs 255, as previously described in connection with the switch structureshown in FIG. 1. When the operating coil or winding 230 of the switch embodiment indicated in FIGS. 10 through 13 is energized and the shaft 326 is released from the magnetically latched position shown in FIG. 11, the associated spring return mechanism 50 will actuate the shaft 326 in a counterclockwise direction from the position shown in FIG. 11 to the position shown in FIG. 13 to thereby also actuate the bushing 322 in a counterclockwise direction due to the configuration of the shaft 326 and the bushing 322.

Assuming that the switch embodiment indicated in FIGS. 10 through 13 is in the normal or off position as indicated by the angular position of the shaft 326 in FIG. 13, the switch structure may be actuated manually to the magnetically latched position by rotating the handle on the shaft 126 in a clockwise direction, as viewed in FIG. 13, and the shafts 126 and 326 will then rotate together in a clockwise direction from the position of the shaft 326 indicated in FIG. 13 to the position indicated in FIG. 11 which corresponds to the magnetically latched position of the shaft 326. In summary, the switch embodiment indicated in FIGS. 10 through 13 is the same as the construction of the switch structure shown in FIG. 1 except that the configuration of the bushing differs from that of the bushing 122 and the shape of the shaft 326 differs from the shape of the shaft 26 as previously described. Both embodiments provide a predetermined amount of rotary lost motion between the corresponding shafts in one direction of rotation and with the shafts rotating together in the opposite direction of rotation toward the magnetically latched position of the shafts which form part of the overall switch structures.

Referring now to FIG. 15, there is illustrated a third embodiment of the invention which comprises a switch structure as previously described except that the shaft 26' is extended forward from the rear portion of the switch parts to support the handle 28' and comprises the only shaft of this switch embodiment. The handle 28' is modified to include an internal opening of the same configuration as the internal opening .in the coupling 122 shown in H68. 7 through 9 to thereby provide a predetermined amount of rotary lost motion between the handle 28 and the shaft 26', which is rectangular in cross section, for a direction of rotation of the shaft 26' away from the ngular position of the shaft 26' which corresponds to the magnetically latched position of the lever arm and the armature which are mounted on the shaft 26' for rotation therewith. The handle 28 is retained axially on the shaft 26 by a screw 29" having an enlarged portion 29A which is not threaded and forms a shoulder which bears against the end of the shaft 26' when the inner threaded end of the screw 29 is screwed into a threaded openingprovided in the end of the shaft 26'. The screw 29' therefore permits limited rotary rotation of the handle 28 on the shaft 26' in accordance with the rotary lost motion provided. Otherwise the structure and operation of. the switch embodiment shown in FIG. 15 is the same a for the switch embodiments previously described.

it is to be understood that in certain applications the switch embodiments previously described may be constructed to permit the manual actuation of the switch structure from the magnetically latched condition to the normal or off operating condition by eliminating the predetermined amount of rotary lost motion between the respective shafts as provided in the switch construction described by mounting the operating handle directly on the shaft which is magnetically latched by the latching means in the different switch embodiments described or by coupling the shaft on which the handle is mounted'to the shaft which is magnetically latched in the different switch embodiments described by a coupling means, such as the coupling 322, which does not provide any rotary lost motion. In other words, the handle 28 in one such modified construction may be mounted directly on the shaft 26 in the first switch structure described and directly on the shaft 326 in the second switch embodiment described.

The apparatus embodying the teachings of this invention has several advantages. For example, a rotary switch structure as disclosed has been found to permit a relatively smaller size and weight than known switch structures of the same general type. The size of such switches is particularly important when the switches are to be mounted on a control panel or switchboard panel along with a plurality of similar switches and other components. The second important advantage of the disclosed switch structure is that is has been found to have a relatively higher speed of operation than known switch structures of the same general type. This advantage is particularly important when such a switch structure is employed to actuate the operation of an associated protective device, such as a circuit breaker.

Since numerous changes may be made in the abovedescribed apparatus and different embodiments of the invention may be made without departing from the spirit and scope thereof, it is intended that all the matter contained in the foregoing description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

We claim as our invention:

1. A switch comprising separable stationary and movable contacts, a rotatable shaft for actuating the movement of said movable contacts between first and second operating positions corresponding to first and second angular positions, respectively, of said shaft, means for biasing the shaft toward said first angular position, a lever arm mounted on said shaft for rotation therewith, a magnetic armature mounted on said lever arm for movement therewith, a stationary magnetic structure including a permanent magnetic member disposed adjacent to said shaft, said magnetic armature being disposed to engage said stationary magnetic structure in the second angular position of said shaft with said permanent magnet member providing magnetic fiux which passes through said magnetic armature to normally latch said shaft in the second angular position against the influence of said biasing means, and electromagnetic means disposed on said stationary magnetic structure and energizable to provide magnetic flux which opposes the magnetic flux from said permanent magnet member, which passes through said armature, to thereby release said armature and said shaft and to permit said shaft to be actuated to said first angular position by said biasing means. g

2. The combination as claimed in claim 1 wherein an additional rotatable shaft is provided having a handle mounted thereon for rotation therewith, and means is provided for coupling said additional shaft to the first-mentioned shaft for rotation therewith for a direction of rotation toward said second angular position and with a predetermined amount of rotary lost motion between said shafts for direction of rotation.

3. The combination as claimed in claim 2 wherein a stop means is provided adjacent said additional shaft .to prevent rotation of said additional shaft in said opposite direction of the opposite rotation beyond said predetermined amount of rotary lost momeans of said handle in said opposite direction of rotation within the limits of said predetermined amount of rotary lost motion, and then released.

6. A switch comprising a generally cylindrical stator housing, a first shaft rotatably disposed in the housing, a rotor rotatable with the first shaft, one or more movable contacts mounted on the rotor, a plurality of spaced stationary contacts mounted on the stator housing, said one or more movable contacts being actuable between first and second operating positions with respect to said stationary contacts upon rotation of said shaft between corresponding first and second angular positions, means disposed adjacent to said shaft for releasably biasing said shaft substantially in the first of said angular positions, a second shaft having a handle thereon for movement therewith rotatably disposed adjacent to said first shaft, means for coupling said first shaft to said second shaft for rotation therewith in a direction of rotation toward said second angular position and with a predetermined amount of rotary lost motion between said shafts in the other direction of rotation, a lever arm mounted on said first shaft for rotation therewith, a magnetic armature mounted on said lever arm for movement therewith, a stationary magnetic structure including a permanent magnet member disposed adjacent to said first shaft, said magnetic armature being disposed to engage said stationary magnetic structure in the second angular position of said first shaft with said permanent magnet member providing magnetic flux which passes through said magnetic armature to magnetically latch said first shaft in the second angular position against the influence of said biasing means, and electromagnetic means disposed on said stationary magnetic structure and energizable to provide a magnetic flux which opposes the magnetic fiux from said permanent magnet member which passes through said magnetic armature, to thereby release said armature and said first shaft and to permit said first shaft to be actuated to said first angular position by said biasing means.

said second shaft is rotated by means of said handle in said other direction of rotation within the limits of said predetermined amount of rotary lost motion and then released.

9. The combination as claimed in claim 6 wherein a handle is coupled to said shaft with a predetermined amount of rotary lost motion between said handle and said shaft for a direction of rotation of said shaft toward the first angular position.

Claims (9)

1. A switch comprising separable stationary and movable contacts, a rotatable shaft for actuating the movement of said movable contacts between first and second operating positions corresponding to first and second aNgular positions, respectively, of said shaft, means for biasing the shaft toward said first angular position, a lever arm mounted on said shaft for rotation therewith, a magnetic armature mounted on said lever arm for movement therewith, a stationary magnetic structure including a permanent magnetic member disposed adjacent to said shaft, said magnetic armature being disposed to engage said stationary magnetic structure in the second angular position of said shaft with said permanent magnet member providing magnetic flux which passes through said magnetic armature to normally latch said shaft in the second angular position against the influence of said biasing means, and electromagnetic means disposed on said stationary magnetic structure and energizable to provide magnetic flux which opposes the magnetic flux from said permanent magnet member, which passes through said armature, to thereby release said armature and said shaft and to permit said shaft to be actuated to said first angular position by said biasing means.

2. The combination as claimed in claim 1 wherein an additional rotatable shaft is provided having a handle mounted thereon for rotation therewith, and means is provided for coupling said additional shaft to the first-mentioned shaft for rotation therewith for a direction of rotation toward said second angular position and with a predetermined amount of rotary lost motion between said shafts for the opposite direction of rotation.

3. The combination as claimed in claim 2 wherein a stop means is provided adjacent said additional shaft to prevent rotation of said additional shaft in said opposite direction of rotation beyond said predetermined amount of rotary lost motion.

4. The combination as claimed in claim 2 wherein a spring biasing means is provided for returning said additional shaft to a predetermined position when said additional shaft is actuated in said opposite direction of rotation.

5. The combination as claimed in claim 2 wherein a spring biasing means is provided adjacent said additional shaft for returning said additional shaft to an angular position corresponding to said second angular position of the first-mentioned shaft when said additional shaft is manually rotated by means of said handle in said opposite direction of rotation within the limits of said predetermined amount of rotary lost motion, and then released.

6. A switch comprising a generally cylindrical stator housing, a first shaft rotatably disposed in the housing, a rotor rotatable with the first shaft, one or more movable contacts mounted on the rotor, a plurality of spaced stationary contacts mounted on the stator housing, said one or more movable contacts being actuable between first and second operating positions with respect to said stationary contacts upon rotation of said shaft between corresponding first and second angular positions, means disposed adjacent to said shaft for releasably biasing said shaft substantially in the first of said angular positions, a second shaft having a handle thereon for movement therewith rotatably disposed adjacent to said first shaft, means for coupling said first shaft to said second shaft for rotation therewith in a direction of rotation toward said second angular position and with a predetermined amount of rotary lost motion between said shafts in the other direction of rotation, a lever arm mounted on said first shaft for rotation therewith, a magnetic armature mounted on said lever arm for movement therewith, a stationary magnetic structure including a permanent magnet member disposed adjacent to said first shaft, said magnetic armature being disposed to engage said stationary magnetic structure in the second angular position of said first shaft with said permanent magnet member providing magnetic flux which passes through said magnetic armature to magnetically latch said first shaft in the second angular position against the influence of said biasing means, and electromagnetic means disposed on said stationary magnetic structure and energizable to provide a magnetic flux which opposes the magnetic flux from said permanent magnet member which passes through said magnetic armature, to thereby release said armature and said first shaft and to permit said first shaft to be actuated to said first angular position by said biasing means.

7. The combination as claimed in claim 6 wherein a stop means is disposed adjacent to said second shaft to prevent said second shaft from rotating in said other direction of rotation beyond said predetermined amount of rotary lost motion.

8. The combination as claimed in claim 6 wherein a spring biasing means is provided adjacent said second shaft for returning said second shaft to an angular position corresponding to the second angular position of said second shaft when said second shaft is rotated by means of said handle in said other direction of rotation within the limits of said predetermined amount of rotary lost motion and then released.

9. The combination as claimed in claim 6 wherein a handle is coupled to said shaft with a predetermined amount of rotary lost motion between said handle and said shaft for a direction of rotation of said shaft toward the first angular position.

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