US2030671A - Electric switch - Google Patents

Description

Feb. 11,- 1936. w|LL|AM$ 2,030,671

ELECTRIC SWITCH Filed July 11, 1954 Invent T 2 Ernest Wiiliawms 5. 8mm by H fi Attor-neg.

l atented Feb. 11, 1936 UNITED STATES PATENT OFFICE.

ELECTRIC SWITCH Ernest Williams, Pittsfield, Mass., asslgnor to General Electric Company, a corporation of New York Application July 11, 1934, Serial No. 734,577

3 Claims. (01. 200-169) of the switch when the circuit controlled thereby is alive. In certain cases it has been found de sirable to so arrange the switchi contacts that 1 a movement of the switch operating member in one direction will cause the switch successively to pass from the open position to the closed position and then on to the grounding position. In

other words the closed position of the switch is 15 intermediate to the open and grounding positions.

Assuch switches have been constructed heretofore, it was possible for the operator to move the switch from the open position through the inter- 20 mediate or closed position to the grounding position so rapidly that the electric. interlock does not, have sufficient time to operate should it happen that the feeder is alive at the time the switch is operated. It is well known to those skilled in'the 25 art that such an interruption of a live high voltage power circuit by the disconnecting switch is extremely hazardous since it may result in personal injury to the operator and in the destruotion of the switch if not in damaging other 30 apparatus in the system. c It is the object of my invention to" provide an improved operating mechanism for a switch of this character whose construction will prevent an operation of the switch in the dangerous manner 35 mentioned above. A further object of my invention isthe provision of such a switch operating mechanism which is simple in construction, reliable in operation and inexpensive to manufacture.

4 My invention will be better understood from the following description taken in connection with-the accompanying drawing, and its scope will be pointed out in the appended claims.

Referring to the drawing, Fig. 1 is a perspective 4 view of an embodiment of my invention, Figs. 2 and 3 are front views thereof with parts broken away, and Fig. 4 is a circuit diagram.

The mechanism comprising my invention is adapted for the operation of various well known 50 forms of disconnecting and grounding switches such for example as that shown in Figs. 9 and 10 of U. S. Letters Patent 1,803,163 to H. N. Beebe, April 28, 1931. The switch is represented in Fig. 4 ,as a three phase switch having three switch 55 arms I mounted on the same shaft represented by the dot and dash line 2 on which is mounted also the operating handle 3. The switch arms I connect with the conductors 4 of a feeder circuit and in the closedcircuit position illustrated connect the feeder with the primary of the transformer 5. 5 The secondary of this transformer may connect with the network through the usual circuit breaker 6. The disconnecting and grounding switch illustrated difl'ers from that shown in the above-mentioned patent in that the closed circuit 10 position is intermediate the open circuit position.

represented by dotted lines, and the grounding position. The switch is represented as provided with an electrical interlock such as that shown in the above-mentioned patent and including the solenoid l. which is connected across one phase winding of the transformer secondary, the arrangement being such that as long as the transformer is energized the switch is locked against movement.

The switch operating mechanism which comprises my invention includes the base lli in which is mounted the switch. operating shaft 2. In order to make an oil-tight joint between the shaft and the base, the boss I: on the base is provided with the packing H which is retained by the gland l3, the latter being bolted to the boss. Longitudinal movement of the shaft is prevented by the set screw H which engages in an annular groove in the shaft. The handle l5 which is fixed to the shaft 2 has the projection l6 on its front face which projection terminates in two similar hooks I] and I8 whose purpose will be described later. ejecting from the rear of the handle I5 is the 'boss 20 through whichextends the retaining plunger 2| which, by engaging in one or the other of the three holes 22, 23 and 24 in the base, retains the shaft 2 and therefore the switch arms I in one or the other of the three diiferent positions. The plunger 2| is shown having a portion 25 01' reduced diameter siurounded by the compression spring 26 by which the plunger is normally urged against the base Ill. The ear 2'! is fixed to the plunger; 2| adjacent to the outer face of the handle and beyond this ear the knurled knob 2! is fixed to the plunger whereby the plunger is withdrawn from the holes in the base and rotated as' will be described later. Fixed also to the plunger II is the collar 30 which has two oppositely extending projections 3| and 32,

one of which, namely 32, being provided with the retaining pin 33 represented by dotted lines. This pin in the position shown engages in the hole 34 in the base. a

When it is desired to move the switch from the open position shown by Fig. 1 to the closed or intermediate position shown by Fig. 2 the operator grasps the knob 28 and withdraws the plunger from the hole 22 and the pin 33 from the hole 34. In this movement the ear 21 slides into the hook it and the projection 3| of the collar 30 is in position to slide upon the track 36 projecting from the base. The handle l5 may now be moved in a clockwise direction, the projection 3| sliding on the track 36, until it reaches the intermediate or closed positionwhen the projections 3i and 32 of collar 30 engage the stops 3'! and 38 respectively which project from the base I 0, further movement of the switch handle thereby being arrested. Since the projection 3| of collar 30 has by this time run off the end of track 36 the plunger 2! is free to engage in the hole 23, thus retaining the handle in the intermediate or closed circuit position. As the plunger 2! engages in the hole 23 the retainin pin so engages in the lower end of the arcuate slot Ml.

In order to move the handle on to the ground ing position the operator must grasp the knob 28 and rotate it in a clockwise direction for approximately 180". In this movement the ear 21 swings to the position adjacent the hool: i'i

and the retaining pin 33 travels in the slot ill to a position near the opposite end thereof. In this rotative movement the projections 3i and 32 of the collar 3t rotate beneath the stops $11 and M. The plunger 20 is now withdrawn from hole 23, the retaining pin 33 also being simultaneously withdrawn from the slot M9, and as the handle is moved to the grounding position the projection iii of collar 3i! rides on the second track ll! projecting from the base, thus holding the plunger in an elevated msitlon until the projection 39 rides off the end of the track when the plunger engages in the hole and the retaining pin 33 engages in the hole The base is provided with a stop til which by engaging the boss Ell limits the above-described clockwise movement of the handle H5. The base also is provided with a similar stop-M at the other side thereof to limit the counterclockwise movement of the handle. By the engagement of the plunger M in the hole 2% the switch is retained in the grounding position.

From the above it will be seen that the oper ator is unable to move the switch rapidly from the open circuit position through the closed circuit position to the grounding position. At least such a movement of the switch cannot be made with such rapidity that the electrical. interlock including the solenoid "ldoes-not have sufificient time to operate should the feeder circuit by any chance be energized at the time the disconnecting switch is operated.

It will be understood that in the reverse movement of the switch handle it the operator must again withdraw the plunger 2 i from the hole El i, move the handle B5 to the intermediate or closed position when the plunger engages the hole and retaining pin engages in slot He then rotates the collar ill to approximately 180, again withdraws the plunger iron]. hole and continues the counterclockwise of the handle 85 to the open circuit position illustrated where the plunger 2| reengages the hole 22. The hooks I8 and i1 serve to prevent any rotative movement of the collar 30 and plunger 2| after the plunger has been withdrawn from either hole 22 or 24 as the case may be and while the projection 3| .is sliding on either track 36 or track 4|. It it is desired to lock the switch handle in any one of its three positions the projection I6 on the handle is provided with the two holes 46 and the car 21 is'provided with the hole 41 whereby a padlock or other suitable looking device may be passed through the aligning holes.

I have chosen the,particular embodiment described above as illustrative of my invention and it will be apparent that various other modifications may be made without departing from the spiritand scope of my invention which modifications I aim to cover by the appended claims.

What I claim as new and desire to secure by Letters Patent of the United States, is:

1. Switch operating mechanism comprising a fixed member, a lever memberpivoted thereto and having a series of successive positions and means for temporarily retaining the lever mem- 7 her in an intermediate position comprising a locking member mounted onone of said members and movable rotatively and longitudinally relative thereto, said other member having a plurality of portions arranged to interlock with different portions of said locking member when the lever member is in said intermediate position, the release of said interlock requiring a. rotative movement of said locking member followed by a longitudinal movement thereof.

2. Switch operating mechanism comprising a switch operating handle arranged to be moved in the same direction from an open circuit position through a closed circuit position to a ground ing position, and means for retaining the handle temporarily in said closed circuit position, said means including a member carried by said handle and constructed to be manually moved longitudinally and rotatively relative to the handle, and a her when the handle reaches said closed circuit,

position, said member and stop having cooperating means requiring successive rotative and longitudinal movements of the member to allow it to pass said stop.

3. Switch operating mechanism comprising a switch operating handle arranged to be moved in the same direction from an open circuit position through a closed circuit position to a grounding position, and means for retaining the handle temporarily in said closed: circuit position, said means including a member carried by said handle and constructed to be manually moved longitudinally and rotatively relative to the handle, and a fixed stop arranged to be engaged by said member when the handle reaches said .closed circuit position, said member and stop havingcooperating portions requiring successive movements of the member longitudinally, rotatively and again longitudinally to allow the memberto pass said step,

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