US2427277A

US2427277A - Electrical switch

Info

Publication number: US2427277A
Application number: US613487A
Authority: US
Inventors: Oscar H Hasselbaum
Original assignee: Joseph Pollak Corp
Current assignee: Joseph Pollak Corp
Priority date: 1945-08-30
Filing date: 1945-08-30
Publication date: 1947-09-09
Anticipated expiration: 1964-09-09

Description

p 1947. o. H. HASSELBAUM ELECTRICAL SWITCH Filed Aug. 50, 1945 FIG. 5

BYaImL INVENTOR.

MW MJ FIG.2

Patented Sept. 9, 1947 ELECTRICAL SWITCH Oscar H. Hasselbaum, Dorchester, Mass., asslgnor to Joseph Pollak Corporation, Dorchester, Mass., a corporation of Massachusetts Application August 30, 1945, Serial No. 613,487

Claims. 1

The present invention relates to an electric switch and more particularly to a multiple position rotary switch in which one position may be a test position. The present invention may be used for combustion engines where one position of the switch is used as a test position and the switch is held normally in that position during the test, returning to a normal position upon release.

In the present invention the rotation of the switch handle is opposed by a helical coil spring when the switch handle is turned to a selected position, as for instance, a test position which automatically forces the handle and the switch back to a normal position. The spring rests in an arcuate recess in the cover of the switch concentric with the turning handle and has no effect on the position of the switch handle on other positions of operation.

The advantages and merits of the present invention will be more thoroughly understood from the description in the specification of an embodiment of the invention shown in the drawings, in which:

Figure 1 shows a sectional view looking towards the cover of the switch in a plane at right angles to axis about which the handle is turned.

Figure 2 shows an exploded view in section through the whole switch taken on the line 2-2 of Figure 1.

Figures 3 and 4 show views of details shown in Figure 2, and

Figure 5 shows a face view of the switch viewing the dial.

In the drawings, i represents a casing or cover generally of thin metal, but other suitable materials may be used. This cover may be built up with a cylindrical surrounding wall 2 from which tabs or fingers 3 extend by means of which the back cover element 4 of insulating material carrying the contact studs and electrical connecting fuses which will be explained in detail afterwards.

The base portion of the cover I is provided, concentrically positioned with respect to its center, indentations or

recesses

5, 6, I, 8 and 9, representing stop positions corresponding to positions I, 2, 3, 4 and 5 respectively shown on the switch dial face it). The base also carries an arcuate formed recess ll concentrically positioned with respect to the center, over which a similarly arcuate formed plate l2 fastened to the base is positioned, -forming a circularly shaped hole closed at one end ii in which a helical coil spring I4 is contained. The plate i2 on the inner pcriphery is cut away from the base for a distance forming a slot IS in which a flat projecting finger i6 projecting'from the disc I! may be moved in contact with the end of the helical coil spring The disc ii at its center is provided with an elongated slot i8 through which the central shaft l3 passes. The shaft is provided with a shoulder 20 permitting elongated faces in the otherwise circular shafts to correspond to the shape of the slot i8. The disc i1 rests on the shoulder 20 of the shaft and is locked by its shape so that the disc will turn with the shaft. Just over the disc I! is the plate or latch member 2| which is carried by the shaft i8 in the same manner as the disc I! by means of the elongated slot 22 in the member 2i. The plate or latch member 2i has a downwardly extending tabor finger 23 which is positioned at such a radius from the shaft l9 so that it successively will engage the

recesses

5, 6, I, 8 and 9, when the shaft is turned. The plate 2i fits freely on the shaft iii in its slot 22 but is forced against the base of the back by means of the spring 24 positioned about the shaft extension 25. Bearing against the top of the spring as viewed in Figure 2, is the contact plate 26 which has an elongated slot 21 like the slots in the members I? and 2i and similarly fits on the shaft extension 25. The contact plate 26 is of insulating material with

conductive studs

28 and 29 connected by a conducting strip 30. The stud 29 will make contact as the shaft is turned and the plate 26 rotates with the contact 3! or the bus yoke 32 in the insulating plate 4.

The insulating plate 4is provided with a series of spaced

contact studs

32, 33, 34, 35, 36 and 31, with which the contact 28 will successively connect as the shaft and the plate 26 is rotated as the stud 29 makes contact with the stud 3| and then the bus yoke 32.

The contact members on the plate 4 project slightly from the plate but a thin disc 38 of this thickness with perforations matching the position of the contact members and their shape fits over the plate to make a smooth continuous surface of metal and insulation so that the

contacts

28 and 28 will ride smoothly over all the opposing contact members.

The plate 4 has a central circular perforation into which the circular end 38 of the shaft it! rests when the plate 4 is brought into position, and the

tabs

3, 3, 3, are bent over on the back of the plate 4. This closes the switch casing and compresses the spring 24 so that the end away from the plate 4 bears against the latch plate so that the pointer 50 is in the position indicated by the legend test," then the arm IQ of the disc I! will be in the slot I5 compressing the spring Id. In this latter position the switch is in test position but as the boss of the member 28 does not rest in one of the recesses in the cover, the

switch handle upon being released from the hand will return the switch and handle to the member 5 or normal position.

The handle 40 with the pointer 50 is held fast on the end of the shaft l9 by the set screw ii in the wall of the handle. The shaft I! on the inside of the case may have a retaining ring 52 which may snap into a groove on the shaft to keep the shaft position within the cover or the shaft may have a shoulder or some other pro- Jection to prevent it from coming out of the cover. The spring 24 serves therefore to press the

contacts

28 and 29 against the contact studs and bus bars and also to press the plate 2| against the cover for retaining the boss in the member 23 in the recesses 5 to 8 when they are engaged.

The shaft l9 beyond the cover works in an externally threaded bushing 53 which is provided with a flange 54 against the outside of the cover.

The dial l0 sets on this flange and a nut 55 30 threads on the bushing to clamp the dial in place.

In the specification no wiring diagram has been shown for the switch may be connected as desired so long as the connections are made for test position and normal position on the connectors shown for whatever device the switch is to be adapted for.

Having now described my invention, I claim:

1. A switch of the type described comprising'a cover member having a flat base section, a sym- 0 metrically positioned shaft extending at right angles to the base section, said base section being recessed in an arcuate section concentric with the shaft, a cover positioned over said arcuate section and a helical spring retained therein, a plate member fixed on said shaft having an extending arm adapted to engage the end of said spring. a second plate member also fixed on said shaft over said first plate member, said second plate member having a dependent boss extending against said base section, said base section having concentrically spaced recesses in which said boss may engage, a switch contact arm engaging said shaft and adapted to be rotated thereby, a fixed switch contact plate closing the end of said cover,

and spring means surrounding said shaft positioned between the switch contact arm and said second plate exerting spring forces in opposite directions on said shaft.

2. In a switch of the type described having a test and normal operating position, a recessed cover, an operating shaft extending through said cover having a handle with an indicating pointer on the external side of said cover, a dial face positioned beneath said pointer at right angles to 4 said shaft, a plate fixed to said shaft within said cover bearing against the inside of the cover and having an arm, a spring having 'one end fixed in the cover and the other end in contact with said arm whereby when the shaft is rotated in one direction the spring is compressed, and means in part fixed on said shaft and in part forced against said cover for holding said shaft in position other than when said spring is compressed.

3. In a switch of the type described having a test and normal operating position, a recessed cover, an operating shaft adapted to be rotated extending through said cover, a plate fixed to said shaft within said cover bearing against the inside 5 of the cover and having an arm, spring means against which said arm bears when said shaft is rotated in one direction beyond-a given point for returning said shaft to a selected position, and means carried by said shaft and co-operating with recesses in said recessed covers for fixing said selected position.

4. In a switch of the type described having a test and normal operating position, a recessed cover, an operating shaft adapted to be rotated extending through said cover, a plate fixed to said shaft within said cover bearing against the inside of the cover and having an arm, a helical coil spring having an arcuate form positioned in an arcuate recess in said cover concentric with said shaft, a cover over said recess having an opening along the inner edge of the recess through which the arm of said plate moves to bear against the end of said spring, and mean carried by said shaft and co-operating with recesses in said cover for locking the shaft in its motion in selected positions.

5. In a switch of the type described having a test and normal operating position, a recessed cover, an operating shaft adapted to be rotated extending through said cover, an arm carried by said shaft having a projecting element adapted to engage corresponding recesses in the cover in the rotation of said shaft, a second arm carried by said shaft and spring means against which said second arm bears to return the same to a selected position when the shaft has been rotated in one direction beyond a selected position, and spring means surrounding said shaft and bearing against said arms in a direction at right angles to their plane of rotation for maintaining tension of the arms against said cover.

OSCAR H. HASSEIBAUM.

REFERENCE S CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 946,045 Hubbard Jan. 11, 1910 FOREIGN PATENTS Number Country Date 333,179 Great Britain Aug. 5, 1930