US2997551A

US2997551A - Selector switch

Info

Publication number: US2997551A
Application number: US761244A
Authority: US
Inventors: Russell C Kinsman
Original assignee: Bryant Electric Co
Current assignee: Bryant Electric Co
Priority date: 1958-09-15
Filing date: 1958-09-15
Publication date: 1961-08-22
Anticipated expiration: 1978-08-22

Description

Aug. 22, 1961 R. c. KINSMAN SELECTOR SWITCH Filed Sept. 15, 1958 Fig.3.

Fig.2.

INVENTOR Russeil C. Kinsman WITNESSES ATTORNEY United States Patent SELECTOR SWITCH Russell C. Kinsman, Pasadena, Calif., assignor to The t Bryant Electric Company, Bridgeport, Conn., a corpo ration of Connecticut Filed Sept. 15, 1958, Ser. No. 761,244 Claims. (Cl. 200-5) The present invention relates generally to electric wirmg devices and more particularly to a novel and versatile selector switch.

In the past, single-pole double-throw and double-pole single throw selector switches have been constructed wherein the movable contacts are operated by a single cam and the travel of the cam is limited by the actuating handle of the switch. For each two and three-position switching arrangement, an individual cam is normally required. Additionally, a diiferent actuating handle is used for two and three-position switching. For twoposition switches, a total of four different cams would be required to cover all switching arrangements and for three-position switching, a total of nine cams would be required to cover all sequences of switch operation. Thus, it may be seen that a total of thirteen different cams and two difierent operating handles would be necessary in order to market selector switches to cover all possible switching sequences.

The present invention eliminates the requirement for manufacturing and stocking a great number of cams and handles by providing a pair of cooperating cam members which may be assembled to achieve all thirteen cam arrangements. The selector switch is additionally provided with a versatile actuating handle which allows either two or three-position switching.

Accordingly, it is a primary object of this invention to provide a novel and versatile selector switch requiring relatively few parts for accomplishing a plurality of switching sequences.

Another object of this invention is to provide a novel and versatile selector switch having an actuating handle for limiting the travel of the operating cams whereby a plurality of ditferent switching positions may be accomplished with the same handle.

Another important object of this invention is to provide a cam operated selector switch for selectively energizing and deenergizing a number of switches in a plurality of sequences through the utilization of a pair of cooperating cam members.

Still another'object of this invention is to provide a novel cam for a selector switch which includes a pair of interengaging cam members.

A still further object of this invention is to provide a versatile cam arrangement for a selector switch including a pair of interengaging cam members and an operating handle cooperating with the cam members for providing a plurality of switching sequences.

For a detailed description of a specific embodiment of this invention, reference may be had to the following detailed description taken in conjunction with the accompanying drawings, forming a part of this application, in which:

FIGURE 1 is an exploded view of a selector switch incorporating the present invention;

FIG. 2 is a front view of the selector switch shown in FIG. 1 and having the operating handle removed;

FIG. 3 is a sectional view of the selector switch shown in FIGS. 1 and 2, taken along the line III-III of FIG. 2 and including the operating handle;

FIG. 4 is a bottom plan view of the operating handle utilized with the switch shown in FIGS. 1 through 3; and

FIGS. 5 and 6 are top and bottom views, respectively,

,. ICC

of the cams utilized by the switch shown in FIGS. 1 through 3.

A selector switch constructed in accordance with the principles of the present invention may comprise a flat support plate 2 constructed of a material having suitable strength, such as sheet steel. The support plate 2 is provided with a circular opening 4 adapted to expose portions of the selector switch to an operating handle 6. A plurality of indexing recesses 8, with an opening at the base of each recess 8, are formed in the support plate 2 and are circumferentially spaced about the opening 4. The support plate 2 is also provided with a travel limiting projection 10 rigidly secured thereto and extending outwardly from the front surface thereof and located adjacent the opening 4.

The operating handle 6 is preferably formed from an insulating material and is generally cylindrical in shape and may be provided with a pointer '12 extending diametrically outwardly from one side thereof for indicating the position of the switch. The under side of the handle 6 is preferably provided with a pair of diametrically opposed recesses 14 adapted for receiving the handle indexing means. The under surface of the handle 6 is also provided with a pair of circumferentially spaced

travel limiting slots

16 and 18 adapted to cooperate with the projection 10 on the support plate 2 for limiting the rotation of the handle 6 in a manner to be described hereinafter. The travel limiting slot 16 is constructed of such length as to allow rotation of the switch handle 6 to two positions and the travel limiting slot 18 is constructed of a greater length as to allow three-position rotation of the handle 6. Indexing of the switch handle is accomplished by a pair of indexing springs 20 and a pair of indexing balls 22.

As seen in FIG. 3, each of the indexing springs 20 is located in an indexing recess 14 on the switch handle. Each indexing ball is adapted to seat on the outer coil of an indexing spring 20 and to be located partly in a recess 14 when engaged in one of the indexing recesses 8 in the support plate 2' to define a switch position. The operating handle 6 is secured to the support plate 2 in a manner to be described hereinafter with the travel limiting projection 10 located in one of the

travel limiting slots

16 or 18. The indexing springs 20 bias the indexing balls 22 into engagement with the support plate 2 and the recesses 8' are located in the path of motion of the indexing balls 22 with the handle 6. It may, therefore, be seen that indexing of the operating handle 6 is accomplished as the indexing balls 22 pass from one of the recesses 8, upon rotation of the handle, to force the indexing balls up into the recesses 14 thereby compressing the springs 20 until the indexing balls 22 are moved to an adjacent recess 8.

It is to be noted that when the travel limiting projection 10 is located in the travel limiting slot 16, the operating handle 6 is movable so that two positions, defined by the recesses 8, may take place and when the travel limiting projection 10 is located in the travel limiting slot 18,"

the operating handle may be moved to three different positions as defined by the recesses 8. It may be seen that either two or three-position switching can be accomplished with the same operating handle depending upon the location of the travel limiting projection 10 relative to the handle. It may be further seen that different numbers of switching positions may be utilized with a single operating handle depending upon the length of the

travel limiting slots

16 and 18 and the number of recesses 8 employed.

The undersurface of the actuating handle 6 is provided with a centrally located outwardly extending circular projection 24 which is adapted to be located in the opening 4 of the support plate 2. A pair of diametrically opposed integral cam engaging projections 26 extend outwardly from the outer end of the projection 24 and are adapted to engage correspondingly spaced recesses in the upper surface of a cam 28 to prevent relative rotation between the cam 28 and the operating handle 6.

In the illustrative embodiment of the invention a pair of identical cams 28 are provided for each selector switch and may be formed from the same material as the handle 6. Each of the cams 28 is generally cylindrical in shape and is provided with

end surfaces

30 and 32. Each cam 28 is provided with a high surface 34 extending radially outwardly from the side surface of the cam adjacent the end surface 32 thereof. The end surface 32 is provided illustratively with six recesses 36 and a pair of outwardly extending projections 38 formed integrally therewith so that each recess 36 and projection 38 is located at the same radial distance from the center of the cam and are equally spaced apart circumferentially, with the projections 33 being diametrically opposed. The end surface 30 of each cam 28 is provided with eight recesses 40 therein spaced at the same radial distance from the center line of the cam and equally spaced apart circumferentially. It is to be noted that the recesses 40 formed on the end surface 30 of the cam 28 are not aligned with the recesses 36 and the projections 38 formed on the end surface 32. Thus, while the

recesses

40 and 36 and the projections 38 are spaced at equal distances from the center line of the cams 28 (FIG. and equal distances apart circumferentially, the recesses 40 are staggered in angular relation, here in the amount of 22 /2, from the recesses 36 and the projections 38. It may, therefore, be seen that the complete actuating cam for the selector switch is assembled by mating the end surfaces 32 of the two earns 28 so that the projections 38 of one of the cams 28 are located in a pair of opposed openings 36 in the other cam 28. Similarly, the projections 38 of the other cam 28 are located in a pair of opposed openings 36 of the one cam 28. It may also be seen that such an assembly of the earns 28 may be madein six different manners so that the high surfaces 34 of the cam may be radially spaced from each other at six different angles. The cam engaging projections 26 of the operating handle 6 are located so that they may engage any pair of diametrically spaced recesses 40 in the surface 30 of a cam 28. It may also be seen that the cam engaging projections 26 may engage the openings 40 of the cam 28 so that the high surface .34 of the cam 28 is located in eight different positions with respect to the handle pointer 12. It may, therefore, be seen that by proper assembly of the two cams 2S and the operating handle 6, substantially any desired two position or three-position switching sequence may be accomplished.

The high surfaces 34 of the earns 28 are adapted to engage and depress push button actuators 42 of switches 44, respectively, at a predetermined rotative position of the handle 6. While the switches are not shown in detail, they may comprise any known switching construction of this type, such as the push button operated snap action switch shown in Patent No. 2,748,214 to Ralph E. Immel, issued May 29, 1956 and entitled Switch.

For purposes of illustration, a pair of switches 44 of the type shown in the noted Immel patent are secured to the support plate 2 on opposite sides of the opening 4 thereof. The switches 44 may be secured in any known manner, such as by screws 46, which extend through openings 48 in the casing of the switches 44 and threadedly engage openings 50 located in the support plate 2 which are aligned with the openings 48 of the switches 44, respectively. The push button actuators 42 of the switches 44 are located to be engaged by the high surfaces 34 of the upper and lower earns 28, respectively, at prede termined rotative positions of the operating handle 6.

-It is to be noted that when the highsurface 34 of a cam 28 engages a push button actuator 42 of a switch 44, actuation of the switch 44 takes place whereby an electrical circuit is made or broken. It is to be noted further that the high surfaces 34 of both the upper and lower cams 28 (FIG. 3) extend outwardly along 21 segment of the axis thereof, which segment is from the under surface of the support plate 2, so that identical switches a may be mounted on the support plate 2 and may be actuated by the high surface 34 of either the upper or the lower cam 23.

To assemble the selector switch, the indexing springs 2d and indexing balls 22 are located in the recesses 14 of the handle 6. The handle 6 is located to engage the upper side of the support plate 2 so that the projection 24 of the handle 6 is located in the opening 4 of the support plate 2. Depending upon whether two or three-position switching is desired, the handle 6 is rotated so that the travel limiting projection 10 is located in either the travel limiting slot 16 or the travel limiting slot 18. The upper and lower cams 28 are assembled in the manner previously described so that the high surfaces 34 thereof are spaced apart at the desired angle. The cams 28 are located on the opposite side of the support plate 2 so that the cam engaging projections 26 of the handle 6 are located in the desired recesses 40 of the upper cam 28 (FIG. 3). Each of the earns 28 is provided with a centrally located opening 52 extending completely therethrough, and the projection 24 of the handle 6 is provided with a centrally located threaded opening 54. The cams 28 are secured to the handle 6 by means of a screw 56 which extends through the openings 52 of the cams 28 and threadedly engages the opening 54 of the handle 6.

Thus it may be seen that by merely providing a pair of identical interengaging cams which may be assembled so that the high surfaces thereof may be spaced apart at a plurality of distances and by providing the cams with means thereon whereby each high surface may be located at a plurality of locations with respect to the pointer of the operating handle, a very versatile selector switch can be constructed whereby a plurality of switching sequences can be accomplished. By the provision of an operating handle which cooperates with the switch support plate to limit the rotation of the bandle, a plurality of switching positions may be utilized for operating the selector switch. Furthermore, while only two cams are shown in the described specific embodiment of the invention, it is to be noted that any number of cams may be stacked in the manner described so that a. corresponding number of switches may be operated thereby in any desired sequence.

Although only one particularform of a selector switch incorporatin the various features of the invention has been shown and described, it is to be realized that other modifications may be made without departing from the spirit and scope of the invention. Accordingly, it is desired that the foregoing description be interpreted in an illustrative and not in a limiting sense.

What is claimed is:

1. In combination, a support plate for a wiring device and an operating handle, said operating handle having a surface thereon located adjacent one side of said support plate and being .movable relative thereto, a plurality of recesses of unequal length located in said surface of said handle, a projection extending outwardly from said one side of said support plate and having a portion thereof located in one of said recesses to cooperate therewith to limit movement of said handle with respect to said support plate, whereby the relative movement of said handle can be varied by locating said projection in different ones of said recesses in said handle surface.

2. In combination, a support plate for a wiring device and an operating handle, said operating handle having a surface thereon located adjacent one side of said plate and rotatable relative thereto, rotation limiting means located on said support plate and said handle surface, one of said means comprising a plurality of arcuate recesses of unequal length located equidistantly from the axis of rotational motion, the other comprising an outwardly extending projection having a portion thereof located in one of said recesses to cooperate therewith to limit the rotation of said handle with respect to said plate, whereby the relative rotation of said handle may be varied by locating said projection in different ones of said recesses.

3. A selector switching comprising, a support plate having an opening extending therethrough, an operating handle located on one side of said support plate having a surface thereon located adjacent one side of said support plate and rotatable relative thereto, means for limiting such rotation located on said handle surface and said support plate, one of said means including a plurality of slots of unequal length located equidistant from the axis of rotational movement, the other of said means comprising a rotation limiting projection having a portion thereof located in one of said slots to cooperate therewith to limit movement of said handle with respect to said support plate, so that the relative movement of said handle can be varied by locating said rotation limiting projection in other ones of said slots, at least one cam mounted on the other side of said support with an end surface thereon engaging the outer end of said handle portion, said cam having a high surface extending outwardly from one side thereof, means for locating said high surface at predetermined positions with respect to said handle including cooperating elements mounted on said outer end of said handle portion and said end surface of said cam, one of said cooperating elements comprising a projection and the other a plurality of recesses, said projection being located in one of said recesses to locate said high surface at one position with respect to said handle, whereby the relative location of said high surface and said handle can be varied by locating said projection in others of said recesses, and means to secure said handle and said cam together with said support plate located therebetween.

4. In combination, a support plate for a wiring device and an operating handle, said operating handle having a surface thereon located adjacent one side of said support plate and being movable relative thereto, a plurality of recesses of unequal length located in said surface of said handle, .a projection extending outwardly from said one side of said support plate and having a portion thereof located in one of said recesses to cooperate therewith to limit movement of said handle with respect to said support plate so that the relative movement of said handle can be varied by locating said projection in different ones of said recesses in said handle surface, at least one cam having a high surface mounted on the other side of said support plate, and means for positioning said cam relative to said handle so that the cam high surface can be accorded varied positions relative to said handle.

5. In combination, a support plate for a wiring device and an operating handle, said operating handle having a surface thereon located adjacent one side of said support plate and being movable relative thereto, a plurality of recesses of unequal length located in said surface of said handle, a projection extending outwardly from said one side of said support plate and having a portion thereof located in one of said recesses to cooperate therewith to limit movement of said handle with respect to said support plate so that the relative movement of said handle can be varied by locating said projection in different ones of said recesses in said handle surface, at least a pair of identical cams mounted on the other side of said support plate, each of said cams having a high surface, means for positioning one of said cams relative to said handle so that its high surface can be accorded varied positions relative to said handle, and means for positioning the other of said cams relative to said one cam so that its high surface can also be accorded varied positions relative to said handle.

References Cited in the file of this patent UNITED STATES PATENTS 912,717 Murphy Feb. 16, 1909 2,480,410 Hammerly Aug. 30, 1949 2,605,367 Cochran July 29, 1952 2,699,479 Gorham Jan. 11, 1955 2,711,450 Carr June 12, 1955