US2241828A

US2241828A - Electrical switch

Info

Publication number: US2241828A
Application number: US214261A
Authority: US
Inventors: Charles H Reynolds
Original assignee: Albert and JM Anderson Manufacturing Co
Current assignee: Albert and JM Anderson Manufacturing Co
Priority date: 1938-06-17
Filing date: 1938-06-17
Publication date: 1941-05-13
Anticipated expiration: 1958-05-13

Description

, May 13, 1941. c. H. REYNOLDS ELECTRICAL SWITCH Filed June 17, 1938 3 Sheets-Sheet 1 0 8 6 d ,4 Q A 0 c ,7 Q Q ra v 4 1 Z J .6 3 5 5 a a 2% w 5 \A 1 2 INVENTOR.

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y 1941' c. H. REYNOLDS 2,241,828

ELECTRICAL SWITCH Filed June 17. 1938 3 Sheets-Sheet 2 INVENTOR.

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ELECTRICAL SWITCH Filed June 17, 1938 s Sheets-sheaf a INVENTOR.

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Patented May 13, 1941 ELECTRICAL SWITCH Charles H. Reynolds, Malden, Mass, assignor to Albert & J. M. Anderson Manufacturing Company, South Boston, Mass., a corporation of Massachusetts Application June 17, 1938, Serial No. 214,261

6 Claims.

This invention relates to an electrical switch and more particularly to an electrical switch of the type enclosed within a casing and having provision for receiving a terminal plug.

The invention has for an object to provide a novel and improved electrical switch of the character specified in which novel and superior locking mechanism is provided to retain the terminal plug in the receptacle when the switch is closed.

Another object of the invention is to provide a. novel and improved electrical switch of the character specified in which the receptacle is provided with locking mechanism adapted to engage the polarizing key of a standard terminal plug and to utilize the polarizing key as a look ing member whereby to prevent withdrawal of the terminal plug when the switch is closed.

A further object of the invention is to provide a novel and superior switch of the character specified in which provision is made for preventing the operation of the switch unless the terminal plug is inserted to its full depth into the receptacle and for preventing insertion of the plug into the receptacle should the switch inadvertently become closed.

With these objects in view and such others as may hereinafter appear, the invention consists in the electrical switch and in the various structures, arrangements and combinations of parts hereinafter described and particularly defined ln the claims at the end of this specification.

In the drawings illustrating the preferred embodiment of the invention, Fig. 1 is a longitudinal sectional view of a switch embodying the present invention; Fig. 2 is a view looking in the direction of the arrows 2-2 in Fig. 1; Fig. 3 is a view of a plug in position to be inserted into the receptacle in Fig. 1; Fig. 4 is a view similar to Fig. 1 with the plug inserted and the switch closed; Fig. 5 is an enlarged detail view looking in the direction of the arrows 5-5 in Fig. 4, and Fig. 6 is a side elevation of the switch casing.

In general, the invention contemplates a novel and improved electrical switch provided with a receptacle for the reception of a terminal plug and in which provision is made for employing the standard polarizing key of the conventional terminal plug as a locking member when the plug is inserted into the receptacle. In the preferred embodiment of the invention, a springpressed latch is adapted to be yieldingly urged behind the polarizing key when the plug is inserted to its full depth into the receptacle, and

provision is made for retaining the latch in its locking position when the switch is closed whereby to prevent withdrawal of the plug until the switch is again opened. Provision is also preferably made in the preferred embodiment of the invention for preventing the operation of the switch member unless the plug is inserted to its full depth into the receptacle and for preventing insertion of the plug in the receptacle unless the switch is open to the end that it would be impossible to insert the plug should the switch in some manner become closed without the plug in place. In the illustrated embodiment of the invention, provision is made for insuring the introduction of the plug into the receptacle in predetermined definite relation whereby to assure alignment of the polarizing key with its locking pawl.

Referring now to the drawings in which the preferred embodiment of the invention is illustrated, l0 represents a casing in which a switch, indicated generally at H, is enclosed. The casing I0 is provided with asocket or receptacle l2 adapted to receive a terminal plug l4 provided with a standard polarizing key IS. The switch ll may preferably comprise the conventional stationary contact jaws l6 mounted upon an insulated base l8, adapted to cooperate with a movable blade 20 secured to a stud 22 journaled in the casing ill. The stud 22, as herein shown. is preferably provided with an operating handle 24 fixed thereon.

As herein illustrated, provision is made for employing the polarizing key l5 as a locking member to retain the plug in the receptacle and to this end a latch member 28, pivotally mounted on a stud 28, is normally disposed in the path of the plug l4 and the polarizing key IS. The

latch member 26 is yieldingly urged in a clockwise direction, viewing Figs. 1 and 4 by a coil spring 29 encircling the stud 28, having one end secured in the latch member 26 and the other end in a stationary part of the casing It. In order to limit the clockwise movement of the latch member, an extension 30 is provided, arranged to normally engage a hub 32. In operation, when the plug I4 is inserted into the receptacle, the polarizing key l5 engages the latch member 26 and yieldingly urges the latter in a counter-clockwise direction until the plug is fully seated. whereupon the latch snaps into place behind the polarizing key.

In the preferred embodiment of the invention, provision is made for locking the latch member 26 in its plug retaining position to prevent withdrawal of the latter when the switch II is moved to its closed position. To this end, a cam 34, operatively connected to the movable switch member is arranged to be moved into the path of the rear face 36 of the latch member 26 to prevent counter-clockwise movement of the latter when the switch is closed. As herein shown, the cam 34 is formed on the hub 32 of an arm pivotally connected to a shaft 42 journaled in the casing l0 and the arm 40 is arranged to be rocked upon movement of the movable switch member through the linkage in cluding an arm 46 secured to the shaft 22, a link 48 connected to the arm 40 and an intermediate arm 50 pivoted on a pin 52. In operation, when the switch is closed, the cam 34 will be rocked behind the latch member 26 to lock the latter in its plug retaining position.

Provision is also preferably made in the preferred embodiment of the invention, to prevent, in a novel manner, the switch from being closed unless the plug is inserted to its full depth in the receptacle. To this end, a pivoted stop member 54 is provided, having an arm 5E yieldingly urged in a counter-clockwise direction, into the path of the plug. The stop member is pivotally mounted upon the shaft 28 and is urged into the path of the plug by a coiled spring 58 having one end secured to the stop member 54 and the other end to a stationary part of the casing l0. Thus,

the tail 60 of the stop member 54 is normally urged into a position to prevent movement of the arm 40, by the engagement of the cam 34 so that the switch cannot be operated until the tail 60 is moved out of the path of the cam. In operation, when the plug is inserted to its full depth in the receptacle, the arm 56 is rocked in a clockwise direction viewing Figs. 1 and 4, thereby removing the tail 60 of the stop member from the path of the cam '34. With the parts in the position, as illustrated in Fig, 4, the switch may be closed, thereby rocking the cam 34 into looking position through the linkage described.

As illustrated in detail in Fig. 5, the casing I0 is v provided with a slot 62 adjacent the receptacle and in alignment with the latch member 26 in order to afford clearance for the key I5 and to insure the proper registration of the plug in the receptacle.

lit will .be observed that if the switch 1 I should in some manner become closed without the plug inserted, such as by manual manipulation of the stop member 54, the latch member '26 will become locked in the path of the plug and prevent the insertion thereof. Thus, it is impossible to insert the plug unless the receptacle is dead and the switch open.

From the description thus far it will be observed that the present switch affords a convendent and reliable method of locking a plug in the receptacle by utilizing the polarizing key of a terminal plug of conventional form as a locking member thereby eliminating the necessity for providing special plugs, having special locking members provided thereon, when it desired to take advantage of this feature. The present invention also enables a simple and rugged construction of a plug locking mechanism to be produced which is efiicient and reliable in operation and capable of withstanding commercial use with minimum attention.

While the preferred embodiment of the invention has been herein illustrated and described,

embodied in other forms within the scope of the following claims.

Having thus described the invention, what is claimed is:

1. An electrical switch having in combination, a switch mechanism including a switch member movable to open and close said switch; a casing enclosing said switch mechanism; a receptacle connected to said casing; a terminal plug adapted to be removably inserted in said receptacle, said terminal plug having a polarizing key; a spring-pressed latch pivotally mounted in said casing, said latch having a detent portion normally lying in the path of said polarizing key adapted to be depressed when said plug is inserted in said receptacle and to automatically return to its initial position and fall in behind said polarizing key when said plug is fully inserted in said receptacle; and a cam member for locking said latch in place after said plug has been inserted in said receptacle, said cam member being connected with said switch member and being movable into locking position upon movement of said switch member to closed position.

2. An electrical switch having in combination, a switch mechanism including a switch member movable to open and close said switch; a casing enclosing said switch mechanism; a receptacle connected to said casing; a terminal plug adapted to be removably inserted in said receptacle, said terminal plug having a polarizing key; a shaft in said casing; a spring-pressed latch pivotally mounted upon said shaft, said latch having a 'detent portion normally lying 'in the path of said polarizing key adapted to be depressed when said plug is inserted in said receptacle and to automatically return to its initial position and fall in behind said polarizing key when said plug is fully inserted in said receptacle; a second shaft in said casing; and a cam member pivotally mounted on said second shaft for locking said latch in place after said plug has been inserted in said receptacle, said cam member being pivotally connected with said switch member and being rotatable into locking position upon movement of said switch member to closed position.

3. An electrical switch having in combination, a switch mechanism including a switch member movable to open and close said switch; a casing enclosing said switch mechanism; a receptacle connected to said casing; a terminal plug adapted to be removably inserted in said receptacle; a spring-pressed latch pivotally mounted in said casing, said latch having an arm normally lying in the path of said terminal plug, said latch being adapted to be partially rotated by said plug upon 7 insertion of said plug in said receptacle; and a cam member connected with said switch member, said latch having a stop element projecting therefrom cooperable with said cam member to prevent movement of said cam member and hence closing of saidswitch unless said plug is fully inserted in said receptacle.

4. An electrical switch having in combination, a switch mechanism including a switch member movable to open and close said switch; a casing enclosing said switch mechanism; a receptacle connected to said casing; a terminal plug adapted to be removably inserted in said receptacle, said terminal plug having a polarizing key; a springpressed latch pivotally mounted in said casing, said latch having a detent portion normally lying in the path of said polarizing key adapted to it will be understood that the invention may be be depressed when said plug is inserted in said receptacle and to automatically return to its initial position and fall in behind said polarizing key when said plug is fully inserted in said receptacle; a cam member for locking said latch in place after said plug has been inserted in said receptacle, said cam member being connected with with said switch member and being movable into locking position upon movement of said switch member to closed position; and a second spring-pressed latch pivotally mounted in said casing, said second latch having an arm normally lying in the path of said terminal plug and being partially rotatable by said plug upon insertion of said plug in said receptacle, said second latch having a stop element projecting therefrom cooperable with said cam member to prevent movement of said cam member and hence closing of said switch unless said plug is fully inserted in said receptacle.

5. An electrical switch having in combination, a switch mechanism including a switch member movable to open and close said switch; a casing enclosing said switch mechanism; a receptacle connected to said casing; a terminal plug adapted to be received in said receptacle, said terminal plug having a polarizing key; a pivotally mounted spring-pressed latch in the path of said polarizing key adapted to be depressed upon insertion of said plug and to automatically fall in behind said polarizing key to yieldingly retain said plug in operative position when the latter is inserted in the receptacle; a pivotally mounted element having a locking cam formed thereon adapted to cooperate with said latch to lock said latch behind said polarizing key when the switch is closed; and means connecting said element with said movable switch member, whereby when said switch member is moved to closed position said element will be rotated so that the cam thereof assumes a position to lock said latch in place.

6. An electrical switch having in combination, a switch mechanism including a switch member movable to open and close said switch; a casing enclosing said switch mechanism; a receptacle in said casing; a terminal plug provided with a polarizing key adapted to be removably inserted in said receptacle; a shaft in said casing; a spring-pressed latch pivotally mounted upon said shaft and having a portion in the path of said terminal plug and adapted to be depressed when said plug is inserted into said receptacle; a second latch pivotally mounted upon said shaft in the path of said terminal plug, and a locking cam cooperable with both of said latch members, said locking cam being cooperable with the first latch member to lock said member in position when the switch is in closed position and being cooperable with said second latch member to prevent closing of the switch unless said plug is fully inserted in said receptacle.

CHARLES H. REYNOLDS.