US3348003A

US3348003A - Switch housing including improved defeatable cover latch means

Info

Publication number: US3348003A
Application number: US546950A
Authority: US
Inventors: Stephen A Mrenna
Original assignee: Westinghouse Electric Corp
Current assignee: CBS Corp
Priority date: 1966-05-02
Filing date: 1966-05-02
Publication date: 1967-10-17
Anticipated expiration: 1984-10-17

Description

Quit. W, 1967 s. A. MRENNA SWITCH HOUSING INCLUDING IMPROVED DEFEATABLE COVER LATCH MEANS 3 Sheets-Sheet 1 Filed May 2, 1966 ||I| II II] IIIII Oct. 17, 1967 s. A. MRENNA SWITCH HOUSING INCLUDING IMPROVED DEFEATABLE' COVER LATCH MEANS Filed May 1966 3 Sheets-Sheet FIG.4.

FEGB.

Oct. 17, 1967 s. A. MRENNA 3,348,003

SWITCH HOUSING INCLUDING IMPROVED DEFEATABLE COVER LATCH MEANS Filed May 2, 1966 I; Sheets-Sheet 3 United States Patent 3,348,003 SWITCH HOUSING INCLUDING IMPROVED DEFEATABLE COVER LATCH MEANS Stephen A. Mrenua, Beaver, Pa., assignor to Westinghouse Electric Corporation, Pittsburgh, Pa., 21 corporation of Pennsylvania Filed May 2, 1966, Ser. No. 546,950 12 Claims. (Cl. 200-50) This invention relates generally to switch structures, and more particularly to enclosed switch structures of the type comprising an enclosure with an openable cover and an enclosed switch operated by means of an operating member that protrudes through an opening in the cover to enable manual operation of the switch when the cover is in the closed position.

It is desirable inthe art of enclosed switch structures to provide various safety features in order to protect workers and others from accidental injury and in order to make it more difficult for unauthorized persons to tamper with the internal parts of the enclosed switch structures.

Accordingly, an object of this invention is to provide an improved enclosed switch structure with improved means for automatically latching the cover closed when the switch is closed.

Another object of this invention is to provide an improved enclosed switch structure with an improved latch means for automatically latching the enclosure cover closed when the switch is closed, which latch means is defeatable to permit opening of the cover when the switch is closed.

Another object of this invention is to provide an improved enclosed switch structure comprising a guard plate that provides an internal pocket-type cavity in which the internal part of an externally operable operating member moves, which guard plate comprises stop means for limiting movement of parts of the switch structure at the two operating positions of the switch.

Another object of this invention is to provide an improved switch structure comprising a contact operating rod and a manually operable operating member connected to the contact operating rod by means of a lost motion connecting means, which switch structure comprises a single operating spring means that biases the contact operating rod and operating member to stable operating positions.

Another object of this invention is to provide an improved, dependable, relatively safe and relatively inexpensive enclosed switch structure.

The invention, both as to structure and operation, together with additional objects and advantages thereof, will be best understood from the following detailed description when read in conjunction with the accompanying drawings.

In said drawings: 6

FIGURE 1 is a top plan view, with parts broken away, of an enclosed switch structure constructed in accordance with the principles of this invention;

FIG. 2 is a side-elevational view, with parts being shown in different positions by means of broken lines, of the enclosed switch structure of FIG. 1;

FIG. 3 is a top plan view, with parts broken away, of the enclosed switch structure of FIG. 1;

FIG. 4 is a sectional view, with parts broken away, taken generally along the line IVIV of FIG. 3;

FIG. 5 is a sectional view, with parts broken away, taken generally along the line VV of FIG. 3;

FIGS. 6 and 7 are views similar to FIG. 5 with the parts being shown in different operating positions; and

FIG. 8 is a sectional view, with parts broken away, taken generally along the line VIII-VIII of FIG. 6.

"ice

Referring to the drawings, there is shown, in FIGS. 1 and 2 an enclosed switch structure 3 comprising an enclosure 5. The enclosure 5 comprises a receptacle 7 and an openable cover 9 supported on the receptacle 7. The' receptacle 7 is a metallic member comprising a generally planar base 11 and sidewall means comprising a pair of opposite generally planar sidewalls 13 and a pair of opposite generally planar endwalls 15. The walls 13, 15

are formed integral with the base and they extend up ward, normal to the plane of the planar base, to an open front. The cover 5, which is movably supported on one of the sidewalls 13 by means of hinges 17, is'pivotally movable about the hinges 17 to open and close the front receptacle opening. The cover 5 comprises a front main body part 19 opposite the base 11 and a flange part 21 bent over from the front part 19 to extend downward a short distance generally parallel to the walls to more elfectively close the receptacle opening in the closed posi' tion of the cover.

The front part 19 of the cover 9 is provided with a first cover opening 23 therein. A resilient tab member 25,

that is supported on one of the endwalls 15, protrudes through the opening 23. The tab 25 has a tang 27 that is positioned over part of the cover 9 when the cover is in the closed position to defeatably latch the cover closed. In order to open the cover the tab 25 is pressed to, align the tang with the opening 23, and the cover is then moved to the open position. When the cover is moved to the closed position, the cover engages the tang 27 to bias the resilient tab 25 to a position permitting the cover to be moved to the closed position, and when the cover reaches the closed position the resilient tab 25 automaticah. 1y returns to the position wherein the tang 27 is positioned over part of the cover to again latch the cover in a closed position.

The cover 9 is provided with a second cover opening 31 therein for receiving an operating member 33 of aswitch structure 35.

The switch structure 35 (FIGS. 3 and 4) comprises an insulating base 37 suitably secured to the base 11. The switch structure 35 is a three-pole switch structure with a pair of fuse clips 39, 41 for each pole supported on the base 37. A separate terminal 43 is provided for connecting each of the fuse clips 39 in an electric circuit. A separate fuse 45 is supported between each pair of fuse clips 39, 41. A separate conducting contact arm support stab 47 is electrically connected to each of the fuse clips 41 and suitably mounted on the base 37. A

separate movable contact arm for each pole, comprising a pair of spaced twin members that straddle the provided for each pole unit of the switch structure. Each of the movable contact arms 47 is pivotally mounted on the associated support 47 by means of a pin member 51. A separate stationary contact stab 53 is provided for each pole unit to cooperate with the associated movable contact arm 49. Each of the stationary contact stabs 53 is supported on the insulating base 37 in a position to cooperate with the associated contact arm 49. Each of the stationary contact stabs 53 is formed integral with a conductor 55. A separate terminal screw 57 is mounted on each conductor 55 to enable connection of the stationary contact stab 53 in an electric circuit.

A separate insulating member 57 is pivotally connected to each of the contact arms 49 by means of a pin member 59. As can be seen in FIG. 3, the spaced twin conductors of each contact arm 49 straddle the associated insulating member 57. Each of the insulating members 57 is providedwith an opening 61 at the front end thereof, and a common operating metallic operating rod 63 extends transversely across the switch structure 35 through the openings 61 of the three insulating members 57 to provide for simultaneous movement of the three movable contact arms 49. As can be seen in FIG. 3, the operatingrod 63, at one end 67 thereof, is supported for rotatable movement in a suitable opening in one sidewall 13. The common operating rod 63 is supported for rotatable movement at the other end thereof on a guard plate 69 that is fixedly supported at the opposite ends thereof on the internal surface of the other sidewall 13 by means of a pair of rivet type securing members 71. As can be seen in FIG. 3, the guard plate 69 is bent-over so that the main body portion thereof is disposed in a spaced relationship from the internal surface of the associated sidewall 13 to provide a pocket-type cavity opening 73 between the guard plate 69 and sidewall 13. As can be seen in FIG. 8, a bearing member 75 is supported in a suitable opening in the guard plate 69, and the end of the operating rod 63 is positioned in the bearing 75 for rotatable support. The operating member 33 is supported, to rotate about the same axis as the operating rod 63, on a spacer 79 that is supported on the bearing 75. The operating member 33 is supported in the pocket-type cavity 73 (FIG. 3). A spring operator 81 is supported on the bearing 75, on the other side of the guard plate 69, to rotate about the same axis as the operating member 33 and operating rod 63. The spring operator 81 is provided with a pair of spaced

lower projections

83, 85. The operating member 33 is provided with a bentover part 87 at the lower end thereof to engage the

projections

83, 85 to operate the spring operator 81 in a manner to be hereinafter described. A spring support 89 (FIG. is pivotally supported at one end thereof on the spring operator 81 by means of a pin 91. The other end 93 of the spring support 89 protrudes through a suitable opening in a support bracket 95 that is fixedly mounted on one sidewall 13. A compression spring 97 is supported on the spring support 89. The spring 97 is biased at one end thereof against the bracket 95 and at the other end against a shoulder portion 99 on the spring support 89. The spring operator 81 is provided with a claw type operating arm structure comprising a pair of spaced

projection members

101 and 103 that straddle the operating rod 63. The guard plate 69 is provided with a pair of bent-in

stop portions

107 and 109 that are formed integral with the guard plate 69 to protrude into the pocket-type cavity opening 73 to limit movement of the operating member 33 at the two operating positions of the operating membet. The guard plate 69 is provided with two bent-over

projections

113 and 115 that are formed integral with the plate 69 and that are provided to engage the operating rod 63 to limit movement of the operating rod 63 in the two operating positions of the operating rod.

As can be seen in FIG. 8, the sidewall 13 is formed with a cup-like formation 119 to accommodate parts of the switch at the internal side of the sidewall 13. Except for the area of the formation 119 the sidewall 13 is a flat planar wall member.

, As is best seen in FIGS. 1-3, the operating member 33 comprises an internal fiat planar part 121 that extends from the pivot support of the member 33 up through the front receptacle opening. The operating member 33 is bent-over to provide an external intermediate part at 123 that extends in the direction normal to the direction of the internal part 121. The operating member 133 is again bent-over to form an external front part 125 that extends outward along a plane generally parallel to the plane of the internal part 121. The described

parts

121, 123, 125 comprise an integral metallic member, and an insulating handle part 127 ismounted on the front part 125. As can be seen in FIGS. 1 and 3, the bent-over part 123 extends over the front end of the sidewall 13 so that the part of the bent-over part 123 and the

parts

125, 127 move outside the front-elevational-view dimensions of the enclosure 5. In operation the internal part 121 of the operating member 33 moves within the pocket-like cavity 73 along a plane parallel to the plane of the sidewall 13. The

front part

125, 127 of the operating member moves outside of the front-elevational-view dimensions of the enclosure 5 along a plane parallel to the plane of the sidewall 13.

The operation will be best understood with reference to FIGS. 3-7. The enclosed switch structure is shown in the open position in FIGS. 3-5. When it is desired to operate the enclosed switch structure to the closed position the operating member 33 is rotated counterclockwise (FIG. 5) from the contact-open or off position seen in FIG. 5 to the contact-closed or on position seen in FIG. 6. During this movement, the lower projection 87 of the operating member 33 engages the projection 83- of the spring operator 81 to rotate the spring operator 81 in a counterclockwise (FIG. 5) direction. This movement serves to move the spring support 89' and compress the spring 97. During this movement, the spring operator 8] is moved to a position wherein the projection 103 thereon engages and moves the operating rod 63. During further movement of the spring operator 81 the spring support 89 and spring operator 81 reach an over-toggle over-center position and the compressed spring 97 collapses the

toggle

89, 81 upward to rotate the operating rod 63 to the closed position seen in FIG. 6 with a snap action. The spring operator 81 and operating rod 63 are stopped in the contact-closed position when the operating rod 63 engages the projection 115 that extends from the guard plate 69. During this operation to the closed position the spring operator 81 moves to a position wherein the projection 85 thereon engages the projection 87 of the operating member 33 to bias the operating member 33 to the fully closed position which position is limited by the engagement of the operating member 33 with the projection 107 that extends from the guard plate 69. As can be seen in FIG. 6, in the closed position of the switch the spring 97 biases the spring operator 81 in a counterclockwise direction to bias the operating rod 63 against the projection 115 and to bias the spring operator 81 against the bent-over part 87 of the operating member 33 to thereby bias the operating member 33 into engagement with the projection 107. Thus, the operating rod 63 and operating member 33 are biased into a stable closed position by means of the operating spring 97.

During the closing movement of the operating rod 63 the three insulating members 57 (FIGS. 3 and 4) are simultaneously moved to simultaneously move the threemovable contacts 49 about the pivots 51 to the closed position. In. the closed position of the contacts, the twin members of each movable contact 49 engage the opposite sides of the associated stationary contact stab 53.

' ment, the projection 87 of the operating member 33 engages the projection of the spring operator 81 to rotate the spring operator 81 in a clockwise direction. As the operator 81 is rotated the projection 101 thereon is moved to engage the operating rod 63 to rotate the operating rod 63 in a clockwise direction. The spring operator 81 and spring support'89 are moved to compress the spring 97 until the

toggle

81, 89 moves over-toggle and overcenter whereupon the toggle collapses downward to the position seen in FIG. 5 with a snap action. This movement moves the operating rod 63 to the open position seen in FIG. 5 to thereby move the three movable contacts 49 to the open position (FIG. 4) with a snap action. The operating rod 63 is stopped in the open position by engagement thereof with the projection 113 of the guard plate 69. The spring 97 biases the

toggle

89, 81 to bias the spring operator 81 in a clockwise (FIG. 5) direction and the projection 83 engages the projection 87 to thereby bias the operating member 33 in a clockwise (FIG. 5) direction which movement is limited by engagement of the operating member 33 with the projection 109 on the guard plate 69. As can be seen in FIG. 5, the operating spring 97 serves to bias the operating rod 63 and the operating member 33 into a stable open position.

As can be seen in FIGS. 1-3, the internal part 121 of the operating member 33 moves within the pocket-type cavity 73 between the main body portion of the guard plate 69 and the internal surface of the associated sidewall 13. When the cover Sis in the closed position the cover opening 31 clears the operating member 33 to permit movement of the operating member 33 between the open and closed positions. The guard plate 69 serves to close off the internal part of the receptacle 5 that houses the live parts of the switch structure while permitting the operating member 33 to extend externally of the enclosure. The guard plate 69 is provided with .a ridge 139 stamped therein toward the internal part of the pocket-type cavity 73 to limit the dimension of the opening of the pockettype cavity 73 at the front of the enclosure. With the provision of the pocket-type cavity 73 it is less likely that a wire or other foreign member will be moved into the internal part of the receptacle in the area of the live parts when the cover is in the closed position.

As can be seen in FIGS. 1 .and 2, the flange 21 of the cover 9 is formed with an opening 141 at the pocket-type cavity 73, and a part 143 of the flange 21 extends alongside the pocket-type cavity 73 a short distance. When the enclosed switch structure is in the closed position, the bent-over intermediate part 123 of the operating member 33 (FIG. 2) is positioned over the part 143 of the flange 21 which part 143 serves as a latch part cooper-ating with the bent-over intermediate latching part 123 to prevent opening of the cover 7 when the enclosed switch structure is in the closed position. As can be seen in FIG. 2, if an attempt is made to open the cover 21 the latch part 143 of the cover 7 will engage the latching part 123 of the operating member 33 to prevent opening of the cover. As can be seen in FIG. 1, when the enclosed switch structure is in the open position the bent over latching part 123 of the operating member 33 is clear of the path of movement of the latch part 143 of the cover 7 so that the cover 7 can be freely opened by releasing movement of the tab 25 and opening movement of the cover in the same manner hereinbefore described.

The latching function of the

parts

123, 143 can be defeated, to permit opening of the cover 7 when the enclosed switch structure is in the closed position, without disturbing the closed position of the contacts. In order to defeat the

latch

123, 143 the operting member 33 is moved from the position seen in FIG. 6 to the position seen in FIG. 7 to clear the latching part 123 out of the path of movement of the latch part 143. As can be seen with reference to FIGS. 6 and 7, the operating member 33 and spring operator 81 reach this defeated position before the projection 101 on the spring operator 81 engages the operating rod 63 so that the cover latch can be defeated without interfering with the closed position of the contacts. When an authorized worker Wants to open the cover without disturbing the position of the closed contacts he can move the operating member 33 to the position seen in FIG. 7 and simultaneously move the tab 25 (FIGS. 1 and 2) to an unlatching position. The worker can hold the

members

33 and 25 against their separate spring biasing means in the defeating position and move the cover 9 upward to the open position. The operating member 33 and cover 7 are shown in broken lines in the open position in FIG. 2.

As can be seen in FIGS. 1, 2 and 5-7, the guard plate 69 protrudes out through the opening 31 in the cover 9, and two

openings

151 and 153 are provided in the guard plate. The opening 151 can receive the hasp of a padlock to permit padlocking of the operating member 33 in the closed position. The opening 153 can receive the hasp of a padlock to permit padlocking of the operating member 33 in the open position. If a padlock is applied in either of the

openings

151 or 153 when the cover 9 is closed, the hasp of the padlock will be positioned in the path of movement of the cover 9 to prevent opening of the cover.

From the foregoing, it can be understood that there is provided by this invention an improved enclosed switch structure that is provided with safety features to protect workers and others from accidental injury and to make it more difiicult for unauthorized persons to tamper with the internal parts of the enclosed switch structure. The operating member 3-3 is supported inside of the cabinet of the switch enclosure. The operating member protrudes out through an opening in the cover of the enclosure to permit manual operation of the enclosed switch when the cover is in a closed position. The operating member is bent-over at the external part thereof, and the bent-over part of the operating member is positioned in the path of movement of the flange part of the cover when the switch is closed. The operating member is spring biased to a stable closed position so that a force is required to move the operating member to a defeated position. The operating member can be moved to the defeated position clear of the path of movement of the flange latch part of the cover without disturbing the closed position of contact structures. With the front part of the operating member being positioned outside of the front-elevational-view dimensions of the enclosure and with a bent-over part of the operating member cooperating with the flange part of the cover to provide the latching function, a relatively short distance of travel of the operating member is required to clear the operating member from the path of movement of the cover in the defeated position.

A guard plate that is mounted on an internal sidewall of the receptacle forms a pocket-type cavity in which the operating member moves. The dimensions of guard plate and the cover opening are such that the guard plate substantially closes olf the internal part of the enclosure, wherein the current carrying parts are disposed, when the cover is in the closed position. The guard plate isprovided with stop means to limit movement of the contact operating rod and to limit movement. of the operating member in the operating positions of the switch structure.

The manually operable operating member is connected to the contact operating rod by means of a lost motion connecting means. In both operating directions the travel of the operating member equals the movement of the operating member to the position where the contact operating rod is picked up plus the movement of the contact operating rod, whereby the same over-center operating spring structure biases both the contact operating rod and the operating member to stable positions against their respective stops in both of the operating positions of the switch.

While the invention has been disclosed in accordance with the provisions of the patent statutes, it is to be understood that various changes in the structural details and arrangement of parts thereof may be made without departing from some of the essential features of the invention. It is desired, therefore, that the language of the appended claims be given as reasonably broad an interpretation as is permitted by the prior art.

What is claimed is:

1. In combination, an enclosure comprising a receptacle and a cover, said receptacle comprising a generally planar base and sidewall means extending from said base normal to said base to form a receptacle-opening at the front of said receptacle, said sidewall means comprising a first generally planar sidewall normal to said base, a

cover supported on said receptacle and movable to open and close said receptacle-opening, said cover having a cover-opening therein, a switch structure supported in said receptacle, said switch structure comprising a sta tionary contact structure and a movable contact structure cooperable with said stationary contact structure, a manually operable operating member supported within said receptacle and extending upward along said first sidewall to said receptacle-opening, said operating member extending through said receptacle-opening and through said cover-opening when said cover is in the closed position and comprising an external part to permit manual operation of said switch when said cover is in the closed position, said operating member being movable between two operating positions in directions parallel to the plane of said planar first sidewall to open and close said contacts, said cover comprising a latch part, said operating member comprising a latching part, and in the closed position of said operating member said latching part being in the path of movement of said latch part to prevent opening of said cover.

2. The combination according to claim 1, said operating member being movable from the closed position thereof toward the open position to a defeated position without disturbing the closed position of said contacts, in said defeated position said latching part being clear of the path of movement of said latch part to permit an opening operation of said cover.

3. The combination according to claim 1, said cover comprising a main body part opposite said base and a flange part extending from said main body part on the external side of said first sidewall generally parallel to said first sidewall, said latch part of said cover comprising a part of said flange part, said operating member comprising an elongated member pivotally supported in proximity to the internal end thereof for pivotal movement in directions parallel to the plane of said first sidewall between open and closed positions, said operating member comprising a bent-over part extending over said first sidewall and an external handle part extending outward from said bent-over part, said external handle part being positioned outside of the front-elevational-view dimensions of said cover, and in the closed position of said contact structure said bent-over part of said operating member extending over said latch part in the path of movement of said latch part to prevent an opening operation of said cover.

4. The combination according to claim 1, said operating member being supported in proximity to the internal end thereof for pivotal movement about an axis that extends parallel to the plane of said generally planar base, said internal part of said operating member extending along said first sidewall through said cover-opening and through said receptacle-opening and comprising a bentover part extending over said first sidewall, said cover comprising a main body part opposite said base and a flange part extending along the outer surface of said first sidewall generally parallel to said first sidewall, said bent-over part of said operating member comprising said latching part and being positioned over a part of said flange part in the closed position of said switch structure to prevent an opening operation of said cover, said switch structure comprising an over-center spring structure operatively connecting said operating member with said movable contact structure, upon movement of said operating member from the closed to the open position said overcenter spring structure being operated over-center to move said movable contact structure to the open position, a first stop means limiting movement of said operating member to the open position, in the open position said over-center spring structure biasing said operating member against said first stop means, upon movement of said operating member from the open position to the closed position said over-center spring structure being operated over-center to move said movable contact structure to the closed position, a second stop means limiting movement of said operating member to the closed position, in the closed position said over-center spring structure biasing said operating member against said second stop means, said operating member being movable from said closed position toward the open position to a defeated position which defeated position is reached before 8 said over-center spring structure is operated over-center and before the closed position of said contacts is disturbed, and in said defeated position said latching part being positioned clear of the path of movement of said latch part to permit opening of said cover.

5. The combination according to claim 1, said cover comprising a main body part opposite said base and a flange part extending from said main body part on the external side of said first side wall generally parallel to said first side wall, said latch part comprising a part of said cover, said operating member comprising an elongated member comprising a first part an intermediate part and an external handle part which parts are movable as an integral unit, said operating member being pivotally supported at the first part thereof for pivotal movement about an axis normal to said first side wall between open and closed positions, said first part extending from the pivot thereof outward along said first side wall through said receptacle-opening, said first part extending through said cover-opening when said cover is in the closed position, said external handle part extending outward from said intermediate part in the same general direction as the direction of extension of said first part with said external handle part being offset from said first part by means of said intermediate part, when said cover is in the closed position and said operating member is in the closed position said intermediate part being positioned over said latch part in the path of movement of said latch part to prevent an opening operation of said cover, and when said cover is in the closed position and said operating member is in the open position said intermediate part being clear of said latch part out of the path of movement of said latch part to permit an opening operation of said cover.

6. The combination according to claim 5, and said external handle part being offset from said first part by said intermediate part such that said external handle part is outside the front-elevational-view dimensions of said cover in all positions of said operating member when said cover is in the closed position.

7. In combination, an enclosure comprising a receptacle and a cover, said receptacle comprising a generally planar base and sidewall means extending from said base normal to said base to form a receptacle opening at the front of said receptacle, a cover supported on said receptacle and movable to open and close said receptacleopening, said cover having a cover-opening therein, said sidewall means comprising a first planar sidewall normal to said base, a switch structure supported in said receptacle, said switch structure comprising a stationary contact structure and a movable contact structure cooperable with said stationary contact structure, an operating rod operatively connected to said movable contact structure, an operating member, an over-center spring operating structure operatively connecting said operating member with said operating rod with lost motion between said operating member and said operating rod, said operating member comprising an internal part supported in proximity to the internal side of said first sidewall and movable along a plane parallel to the plane of said first sidewall, said operting member extending through said receptacle-opening and through said cover-opening and comprising an external handle part, said operating member being movable between opened and closed positions to operate said over-center spring structure to thereby move said operating rod between opened and closed positions to open and close said contacts, a guard plate supported in proximity to the internal surface of said first sidewall to provide a pocket-type cavity between said guard plate and the internal surface of said first sidewall, said internal part of said operating member moving within said pocket-type cavity, said cover-opening having a dimension to exposed substantially only the front of said pocket-type cavity in the closed position of said cover, and said guard plate comprising a pair of spaced projections positioned to limit movement of said operating rod at said open and closed positions.

8. The combination according to claim 7, said guard plate comprising a second pair of spaced projections positioned to limit movement of said operating member at said open and closed positions, in the open position of said switch structure said over-center spring structure biasing said operating rod against a first projection of said first pair of projections and said over-center spring structure biasing said operating member against a first projection of said second pair of projections, and in the closed position of said switch structure said over-center spring structure biasing said operating rod against the second of said first pair of projections and said over-center spring structure biasing said operating member against the second of said second pair of projections.

9. A switch structure comprising a stationary contact structure, a movable contact structure movable into and out of engagement with said stationary contact structure, an operating rod movable to move said movable contact structure, a manually operable operating member, lostmotion connecting means operatively connecting said operating member with said operating rod, a first pair of stops limiting movement of said operating rod in the closed and open positions, a second pair of stops limiting movement of said operating member in the closed and open positions, an over-center spring structure operable between over-center positions upon operation of said operating member to operate said operating rod to close and open said contacts, and in each of the closed and open positions of the switch structure said over-center spring structure biasing the operating rod against the associated stop and biasing the operating member against the associated stop.

10. A switch structure according to claim 9, said operating rod and said operating member being pivotally movable about the same axis.

11. A switch structure according to claim 9, said lostmotion connecting means comprising a spring operator having a first pair of spaced operating parts and a second pair of spaced operating parts, said operating rod being positioned between said first pair of spaced operating parts, said operating member comprising an actuating part positioned between said second pair of spaced operating parts, in the closed position of said switch said overcenter spring structure biasing said spring operator in a first direction to bias a first operating part of said first pair of operating parts against said operating rod to thereby bias said operating rod against a first stop of said first pair of stops and to bias a first operating part of said second pair of operating parts against said actuating part to thereby bias said operating member against a first stop of said second pair of stops, and in the open position of said switch said over-center spring structure biasing said spring operator in a second direction opposite from said first direction to bias the second operating part of said first pair of operating parts against said operating rod to thereby bias said operating rod against the second stop of said first pair of stops and to bias the second operating part of said second pair of operating parts against said actuating part to thereby bias said operating member against the second stop of said second pair of stops.

12. A switch structure according to claim 11, said operating rod said operating member and said spring operator all being supported for pivotal movement about the same axis.

References Cited UNITED STATES PATENTS 3,059,072 10/1962 Mekelburg et al. 200- 3,213,224 10/1965 Mrenna et al. 200-50 3,240,888 3/1966 Rys et al. 200-50 3,259,705 7/1966 Freese et al 20050 'ROBERT K. SCHAEFER, Primary Examiner.

R. S. MACON, J. R. SCOTT, Assistant Examiners.

Claims

1. IN COMBINATION, AN ENCLOSURE COMPRISING A RECEPTACLE AND A COVER, SAID RECEPTACLE COMPRISING A GENERALLY PLANAR BASE AND SIDEWALL MEANS EXTENDING FROM SAID BASE NORMAL TO SAID BASE TO FORM A RECEPTACLE-OPENING AT THE FRONT OF SAID RECEPTACLE, SAID SIDEWALL MEANS COMPRISING A FIRST GENERALLY PLANAR SIDEWALL NORMAL TO SAID BASE, A COVER SUPPORTED ON SAID RECEPTACLE AND MOVABLE TO OPEN AND CLOSE SAID RECEPTACLE-OPENING, SAID COVER HAVING A COVER-OPENING THEREIN, A SWITCH STRUCTURE SUPPORTED IN SAID RECEPTACLE, SAID SWITCH STRUCTURE COMPRISING A STA TIONARY CONTACT STRUCTURE AND A MOVABLE CONTACT STRUCTURE COOPERABLE WITH SAID STATIONARY CONTACT STRUCTURE, A MANUALLY OPERABLE OPERATING MEMBER SUPPORTED WITHIN SAID RECEPTACLE AND EXTENDING UPWARD ALONG SAID FIRST SIDEWALL TO SAID RECEPTACLE-OPENING, SAID OPERATING MEMEBR EXTENDING THROUGH SAID RECEPTACLE-OPENING AND THROUGH SAID COVER-OPENING WHEN SAID COVER IS IN THE CLOSED POSITION AND COMPRISING AN EXTERNAL PART TO PERMIT MANUAL OPERATION OF SAID SWITCH WHEN SAID COVER IS IN THE CLOSED POSITION, SAID OPERATING MEMBER BEING MOVABLE BETWEEN TWO OPERATING POSITIONS IN THE DIRECTIONS PARALLEL TO THE PLANE OF SAID PLANAR FIRST SIDEWALL TO OPEN AND CLOSE SAID CONTACTS, SAID COVER COMPRISING A LATCH PART, SAID OPERATING MEMBER COMPRISING A LATCHING PART, AND IN THE CLOSED POSITION OF SAID OPERATING MEMBER SAID LATCHING PART BEING IN THE PATH OF MOVEMENT OF SAID LATCH PART TO PREVENT OPENING OF SAID COVER.