US2219878A - Switch - Google Patents

Description

Oct. 29, 1940. I TURCK 2,219,878

Filed July 2, 1936 26' 11 INVENTOR.

Patented Oct. 29, 1940 UNITED STATES SWITCH Joseph A. V. Turck, Wilmette, 111., assignor to Felt a Tar-rant Mfg. 00., Chicago, 111., a corporation of Illinois Application July 2, 1936, Serial No. 88,527

1 Clam (Cl. 200-155) This invention relates in general to switches for controlling electric circuits, and especially to switches of the snap orrotary type.

A principal object of the invention is the provision of a switch for controlling an electric circuit which automatically reverses the polarity or direction of flow of the current to the circuit upon each successive manual circuit closing operation thereof.

Another important object of the invention is the provision of such a switch in which each alternate successive operation opens the electric.

circuit controlled thereby.

A further object of the invention is the provision of such a switch which is so constructed as to necessitate the use of but four binding posts. Another important object of the invention is to provide a pole changing switch of simple and durable construction and very compact -form or arrangement of parts, so that it will occupy a minimum amount of space and will be able to withstand hard usage with a high degree of safety.

Numerous other objects and advantages of the 5 invention will be apparent as it is better under- .stood from the following description, which, when taken in connection with the accompanying drawing, discloses a preferred embodiment thereof. In the drawing,

Figure 1 is an elevational view of a switch embodying the features of the instant invention; Fig. 2 is a side elevation, partly in section, of the'device of Fig. 1 with the exterior connections and operating mechanism and the cover removed;

Fig. 3 is an enlarged horizontal sectional view taken substantially on-the line 3-3 of Fig. 1;

Fig. 4 is an enlarged detail vertical section showinga binding post, brush holding post and conductor interconnecting the same;

Fig. 5 is a detail vertical section through th rotor mechanism; and T Fig. 6 is a view similar to Fig. 5 with the outer cam disc removed. I

Referring more particularly to the drawin the main portion of the switch disclosed therein is housed within a casing comprising a substantially circular base member I i and a flanged cap member l2 mounted thereon, both of said members preferably being cast or otherwise formed from some suitable non-conductive ma,-

terial. The base ll may be provided with a plu-.

rality of integral lugs or ears l3 having suitable apertures therein for engagement by screws or cam 42 from the base member il.

bolts l4 which are adapted to secure the casing in any desired position to a supporting member or wall IS.

The base member II is provided with an annular flange l6 (Figs. 2, 3 and 4) within which are 5 embedded the lower ends/of four circumferentially spaced binding posts l1, l8, I9 and 21. Also embedded within the annular ring it and electrically connected at one end to each of these binding posts, respectively, are four substantially 10 arcuate- shaped connectors 22, 23, 24 and 25. It is to be understood that the base'member II is preferably cast around the several members H to 25. The other end of each of the connectors 22, 23, 24 and 25 is provided with a radially disposed 15 projection 26 formed integrally therewith and extending inwardly from the inner surface of the annular ring it. To the free end of those projections 26 associated with the connectors 22 and 24 are fixed short posts 21 and 28, respectively, 20 which extend outwardly therefrom in parallel relationship to the binding posts I1 and i9. Similarly, longer posts 29 and 3i are secured to the projections 26 associated with the connectors 23 and 25, respectively. These posts 21, 28, 29 and 25 3| serve as supports and electrical connections for spring contact brushes 32, 33, 34 and 35, respectively.

The outer ends 36 of eachof the brushes 32, 33, 34 and 35 fit like a key in a key slot 31 pro- 30 'vided in the upper end of each of the posts 2'l,'

28, 29 and 3| (Figs. 2 and 4). It will also be noted that each brush or spring contact as it emerges from this keyed relation with its respective post takes a scroll form of two turns about 35 said post, which provides spring tension urging, the inner ends of the brushes towards the center of the base member ll. Rigidly secured to the base member II and extending outwardly from the center thereof is 40 a fixed stud shaft or hollow post 38, the base member H being preferably cast around the inner end of this shaft. A rotor, indicated generally by reference numeral 39 is mounted for rotation on the shaft 38. The rotor 39 comprises a pair of cam toothed discs 4| and 42 which are made up irom any suitable non-conductive material, such as that from which the members II and i2 are formed, and are provided with eight cam surfaces or teeth on their outer peripheral surfaces. The cam discs 4| and 42 are separated by a center partition disc 43, and two end partition discs 44 and 45 are positioned adjacent the outer surfaces thereof, the disc 44 separating the A hollow 55 ratchet gear 45 is positioned adjacent the partition disc 45, and a metallic collar or hub 41 extends through suitable axial apertures in each of the members 4| to 45. These several members are preferably rigidly secured together by a plurality of rivets 48 to form the complete rotor unit 39.

Every other tooth or cam face of the disc 4| is provided with metallic inserts 5|, 52, 53 and 54 (Figs. 5 and 6) which are flush with the cam surfaces of these teeth. As shown in Fig. 6, the inserts 5 I, 52 and 53 are interconnected by a metallic conductor 55 which is provided withv a free end 55 passing through the center partition 43. On the other side of the partition 43 the end 55 of the conductor 55 extends radially outward and is connected to a metallic insert in the disc 42 similar to the insert 54 in the disc 4 I. The insert 54 in the disc 4| is connected to a conductor 51 which passes through the center partition 43 and is connected on the other side of the Partition to a conductor similar to the conductor 55, which which the ends of the conductors may be posi-' tioned.

The inserts 5| to 54 in the cam disc 4| form electrical contacts for the brushes 34 and 35 (Fig,

5), while the inserts on the cam disc 42 form.

similarly disposed electrical contacts for the brushes 32 and 33 (Fig. 6). Due to the spring tension imposed upon the brushes, their inner ends will be held in contact with the outer cam surfaces of their respective discs 4| and 42. As

40 will be noted in Fig. 5, the inner ends of the brushes 34 and 35 co-act with the teeth of the disc 4| to prevent clockwise rotation thereof. The inner ends of the brushes 32 and 33 terminate in inwardly bent hook shaped portions which 5 are adapted to co-operate with the teeth of the cam disc 42, as shown in Fig. 6, to prevent clock wise rotation thereof. This is the reason for the posts 21 and 25 being shorter than the posts 29 and 3|, the former supporting the brushes 32 50 and 33 in the plane of the inner disc 42, and the 55 35 and extends outwardly through the cap memlatter supporting the brushes 34 and 35 in the plane of the outer disc 4|.

Referring to Figs. 1 to 3, a short shaft 5| is positioned for rotation in the hollow stud shaft ber l2. An arm 52 is secured to the shaft 5| adjacent the inner surface of the cap member l2,

and is provided with a ratchet pawl 53 pivotally mounted on one end thereof for engagement with the teeth of the internal ratchet gear 45. A suit- 70 otally mounted on a shaft 55 which is secured in any suitable manner to the supporting memher or wall IS. The free end of the lever 51 is provided with a suitable finger piece 59. A coil spring 1| is secured at one end to the wall l and 75 at the other end to the lever 51 to urge the latter in a counter clockwise direction, as seen in Fig. 1.

The binding posts l1, I8, I 9 and 2| are made hollow to receive spring contact plugs 12 (Fig. 4) which are fixed to the ends of lead wires or conductors 13, 14, and 15 and form a split thimble bent back upon and covering the fabric of the wires, the latter forming a cushion to hold the split part of the plug 12 expanded against the inner walls of the binding posts. The lead wires 13 and 14 are adapted to be connected to any suitable source of electric current, while the leads 15 and 15 are adapted to be connected to the electrical circuit which it is desired to control by means of the above described switch.

The operation of the switch is as follows: clockwise movement, as seen in Fig. 1, of the manually operable lever 51 through the agency of the finger piece 59 will result in counter-clockwise rotation of the shaft 5|, arm 52 and ratchet pawl 53, to rotate the ratchet gear 45 and consequently the rotor 39 in a counter-clockwise direction (Figs. 2, 5 and 6) Upon release of the manually operable lever 51, the spring 1| will return the same and the shaft 5| and ratchet pawl 53 to their normal position, as shown in Figs. 1 and 2. Such return or clockwise movement of the rotor 33 will be prevented, however, by the free ends of the brushes 32, 33, 34 and 35 engaging against the radial surfaces of the teeth of the cam discs 4| and 42. The several operating members are so proportioned that a single manual operation of the lever 51, as above described, will revolve the rotor 39 one-eighth of a revolution in a counterclockwise direction. Every other operation of the manually operable lever 51 will therefore result in the free ends of the brushes 32 to 35 contacting a blank tooth of their respective cam discs 4| and 42, so that there will be no connection between the leads 13, 14 and 15, 15, respectively.

With the rotor 39 in any of its other four possible positions, however, certain of the inserts 5|, 52, 53 and 54 will be engaged by the free ends of the brushes 32 to 35. In any such position, the two pair of leads 13, 14 and 15, 15 will be electrically interconnected to close the circuit represented by the leads 15, 15, or supply current from the leads 13, 14 to said circuit. In the position of the rotor shown in the drawing, assuming wire 13 to be the positive lead, current will flow from this lead through the brush 34 to the insert 5| on the cam disc 4|, through the conductor 55 to the insert 53, brush 35, conductor 25 and binding post 2|, to the lead 15. At the same time, the return flow of current will be from the lead 15 through the brush 32, insert 53, connector 55 and insert 5| on the cam disc 42, to the brush 33, binding post l9 and lead 14.

The next manual operation of the switch through the agency of the finger piece 59 will rotate the rotor 39 one-eighth of a revolution to position blank cam surfaces of the discs 4| and 42 in engagement with the brushes 32 to 35 to break the connection between the leads 13, 14 and 15, 15, or open the circuit.

The next manual operation of the switch will rotate the rotor 39 another one-eighth of a revolution to bring the inserts 52 and 54 into engagement with their respective brushes. In this insert 54 and connector 51 on the cam disc 4I,'

through the connector 55 and insert 52 on the cam disc 42, to'the brush 33, binding post I9 and lead 14.

From the foregoing description, it will be readily apparent that, regardless of which of the two leads 13, H is connected to the positive side of the line, the flow of current therefrom to the controlled circuit, as represented by the leads 15 and I6, will be automatically reversed upon each alternate successive manual operation of the switch. Each of these circuit closing operations of the switch will be interposed by a circuit breaking or opening operation thereof. Such operation. of the switch is of particular importance when using direct current, since it prevents the usual pitting or breaking down of one contact point and building up of the other, which normally results when the flow of current is always in the same direction. The above described arrangement of the parts of the switch provides a simple and durable construction that will occupy a minimum amount of space, and results in a switch that will be able to withstand extremely hard usage with a high degree of safety. As will'be noted from Fig. 3, the rotor mechanism is designed in a very close and compact form with the brushes 32 and 33 in very close juxtaposition with the brushes 35 and 34, respectively. The center insulating partition 43, however, prevents the possibility of any shorts or other interferences between the adjacent brushes. a

It is thought that the invention and many of its attendant advantages will be understood from the foregoing description, and it will be apparent that various changes may be made in the form, construction and arrangement of theparts without departing from the spirit and scope of the invention or sacrificing all of its material advantages, the form hereinbefore described being merely a preferred embodiment thereof.

I claim:

In a pole reversing switch, a first pair of con-' tacts, a second pair of contacts, a first cam disc, 21. second cam disc mounted for rotation with said first cam disc relative to said contacts, a plurality of contacts mounted on each of said cam discs, some of the contacts on said first disc being electrically connected with a contact on said second disc, and some of the contacts on said second disc being electrically connected with one of the contacts on said first disc, whereby successive, similar increments of rotation imparted to said cam discs will alternately connect and disconnect said pairs of contacts through certain of said contacts on said discs, each alternate connection of said contacts reversing the connection between said first and second pairs of contacts from that obtained from the other alternate connections therebetween, a manually operable member having only a limited extent of movement and adapted to be repeatedly operated, and means interconnecting said member and said cam discs for moving the latter through a said increment of rotation in one direction only upon each operation of the former.

' JOSEPH A. V. TURCK.

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