US2134207A - Electric switch - Google Patents

Description

Oct. 25, 1938. F, J RUSSELL 2,:134207 I ELECTRIC SWITCH Filed June 22, 1936 INSULATION Patented Oct. 25, 1938 UNITED STATES ELECTRIC SWITCH Frank J. Russell, Wauwatosa, Wis., assignor to Cutler-Hammer, Inc., Milwaukee, Wis., a corporation of Delaware This invention relates to electric switches, and more particularly to auxiliary control switches for use in connecti n with electromagnetic contactors and other c trol apparatus.

Auxiliary control switches having a stationary contact and a cooperating movable leaf spring contact which is fixed to a stationary support are commonly employed in electromagnetic contactors to establish a maintaining circuit for the contactor uponclosure thereof. However, in practice it'has .been found that auxiliary control switches of this type are difiicult to adjust and are also objectionable due to the fact that the leaf spring contact is likely to break or become permanently bent.

The present invention has among its objects to provide an improved auxiliary control switch which overcomes the aforementioned objections.

Another object is to provide a reliable, and efllcient control switch consisting of a relatively small number of rugged and inexpensive parts which can be readily manufactured and assembled.

Various other objects and advantages of the invention will hereinafter appear.

The accompanying drawing illustrates an embodiment of the invention which will now be described, it being understood that various modifications may be made in the embodiment illustrated without departing from the spirit and scope of the appended claims.

In the drawing,

Figure 1 is a side elevational view of an electromagnetic reversing switch having auxiliary control switches embodying the invention associated therewith;

Fig. 2 is a sectional view on line 2- -2 of Fig.

. and

Fig. 3 is a, diagrammatic view illustrating'the control circuits for the switch shown in Fig. 1.

The drawing illustrates a reversing switch including a pair of 3-pole electromagnetically operated contactors and 2 mounted side by side upon a supporting plate 3. Each ofsaid contactors is provided with an operating magnet 4, stationary contacts 5 carried by an insulating base 6 fixed to plate 3, and cooperating movable contact fingers 'l yieldingly mounted upon an insulating block 8. The operating magnet of each switch includes a magnet winding 9 carried by a field member Ill fixed to plate 3 and a verv lng part 20 located in front of said contact finger der 28.- The leg 21 of operating member 20 is lever l3 occupies an intermediate position and PATENT OFFICE means comprises a horizontally arranged insulating lever l3 pivoted intermediate its ends upon a pin l4 carried by a bracket l5 fixed to plate 3. Lever l3 extends between the upper ends of the insulating blocks 8 of switches l and 2 and as is apparent from Fig. 2 said lever cooperates with said insulating blocks to prevent'closure of the contactors l and 2 simultaneously.

Each of the contactors l and 2 has an auxiliary control switch i 6 mounted upon its associated insulating base 6. Such switches are of like construction and each includes a contact finger I! having one end mounted upon a supporting post IS, a stationary contact post I9 located at the opposite end of said contact finger, and an operatand carried by said supporting post. Contact post l9 and supporting post I 8 each have a terminal plate 2! associated therewith and said posts and their associated terminal plates are secured to base .6 by screws 22. Supporting post i8 is provided with a square shank 23 having a pin 24 projecting from the front end thereof, and conta t finger I! is provided with an opening for receiving said pin and is also provided with a hooked end portion 25 which engages one of the side faces of said shank to hold said contact finger against rotation upon said pin. The operating part 20 is provided with legs 26 and 2'l which are offset withrespect to each other at a point intermediate. the ends of contact finger IT to provide a shoulprovided with an opening for receiving pin 24 and said leg bears against the front face of contact finger l1 and is provided with a hooked end portion 29 which overlaps the hooked end portion 25 on said contact finger to prevent rotation of said operating member upon pin 24. Contact finger l1 and its associated operating part 20 are held in assembled relation upon supporting post l8 by a coil spring 30 which surrounds pin 24 and is held under compression between the leg 21 of operating member 20 and a washer 3| fixed to the end of said pin.

When contactors l and 2. are in open position each of the contact fingers ll of the auxiliary control switches I6 is held in engagement with the front face of shank 23 by its associated spring 30 to disengage the same from its associated stationary contact post l9. However, upon closure ofeither of the contactors the operating member 20 of its associated auxiliary switch is moved inwardly by engagement of lever l3 with the leg 26 of said operating member. During initial inward movement of operating member 20 the rear face of the leg 21 thereof is maintained in engagement with the front face of contact finger I1 and said contact finger is'rocked upon the edge 32 of shank I8 against the action of spring 30 8 0 into engagement with its cooperating stationary contact post i9. Upon continued inward movement of operating member 20 the leg 21 thereof is tilted with respect to contact finger 11 against the action of spring 30. The shoulder 28 of said operating member then bears on said contact finger at a point intermediate the ends thereof to hold the same in closed position. Thus each of the auxiliary control switches is adapted to be closed upon initial closing movement of its associated contactor, and as is apparent tilting of the operating member 20 with respect to the contact finger l1 permits full movement of the contactor into closed position without subjecting said finger to an excessive operating force.

Referring now to Fig. 3, the same diagrammatically illustrates the operating windings of the contactors i and 2 and also the auxiliary control switches associated with said contactors. A supply circuit for said operating windings is indicated by lines L ---L and the control means therefor includes a normally closed push button 33 and a pair of normally open push buttons and 35. Upon depression. of push button 34 the operating winding of contactor I is connected across lines L L through the medium of push button 33 and upon response of said contactor push button 34 can be released and an energizing circuit for the operating winding of said contactor is maintained through the medium of its auxiliary switch I6 and push button 33. Upon depression of push button 35 the operating winding of contactor 2 is connected across lines L -L through the medium of push button 33 and upon response of said contactor push button 35 can be released and an energizing circuit for said operating winding is maintained through the medium of its associated auxiliary switch i6 and push button 33. Upon closure of either of the reversing contactors the maintaining circuit therefor may be interrupted by depression of push button 33.

In connection with the foregoing it should be noted that the leg 26 of the operating member 20 can be bent inwardly or outwardly with respect to the leg 2! of said member to provide for closure of the contact finger at the proper instant. Also it should be noted that the above described auxiliary switch may be modified by arranging the stationary contact so that the same is engaged by its associated contact finger when the latter is in normal position.

What I claim as new and desire to secure by Letters Patent is:

1. In a control switch, in combination, a rigid contact finger, a cooperating stationary contact located at one end thereof, a fixed support 10- cated at the opposite end of said finger and supporting said finger for rocking motion into and out of engagement with said stationary contact, a member having a part to lie against said finger, said member being supported by said finger for rocking movement relative thereto, resilient pressure means common to said finger and said memberbiasing said finger out of engagement with its cooperating stationary contact and pressing said member against said finger to normally hold the same in a given position with respect to said finger, and an operating element for moving said finger into engagement with its cooperating stationary contact by pressure exerted on said member at a point to cause said member to rock on said finger against the action of said resilient pressure means as movement of said operating element is continued after engagement of said finger with its cooperating stationary contact.

2. In a control switch, in combination, a rigid contact finger, a cooperating stationary contact located at one end thereof, a stationary support located at the opposite end of said finger and engaging one side thereof, a member engaging said finger on the side opposite said support, said finger and said member being mounted upon said support to rock with respect thereto, and said member being also capable of rocking movement on said finger, a spring biasing said finger out of engagement with its cooperating stationary contact and pressing said member against said finger to normally hold the same in a given position with respect thereto, and an operating element for moving said finger into engagement with its cooperating stationary contact by pressure exerted on said member at a point to cause said member to rock on said finger against the action of said spring as movement of said operating element is continued after engagement of said finger with said contact.

3. In a control switch, in combination, a rigid contact finger, a cooperating stationary contact located at one end thereof, a stationary support located at the opposite end of said finger and engaging one side thereof, a member engaging said finger on the side opposite said support, said finger and said member being mounted upon said support to rock with respect thereto, and said member being also capable of rocking movement on said finger, a pin mounted on said support and extending through openings in said finger and said member, a spring carried by said pin and engaging said member to bias said finger out of engagement with its cooperating stationary contact and to normally hold said member in a given position with respect to said finger, and an operating element for engaging said member to eifect movement of said finger into engagement with its cooperating stationary contact against the action of said spring and to also rock said member on said finger against the action of said spring as movement of said operating element is continued after engagement of said finger with its cooperating stationary contact.

4.-In a control switch, the combination with a rigid contact finger, of a cooperating stationary contact located at one end thereof, a fixed support located at the opposite-end of said finger and engaging one side thereof, a member engaging said finger on the side opposite said support, said finger and said member being capable of rocking movement upon said' support, and said member being also capable of rocking movement with respect to said finger, a pin mounted on said support and extending through openings in said finger and said member, a spring carried by said pin and engaging said member to bias said finger out of engagement with its cooperating stationary contact and to normally hold said member in a given position with respect to said finger, and an operating element for engaging said member to efiect movement of said finger into engagement with its cooperating stationary contact, said element exerting pressure on said member at a point intermediate the ends of said fingerto cause rocking movement of said member with respect to said finger as movement of said operating element is continued after engagement of said finger with its cooperating stationary contact.

FRANK J. RUSSELL.

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