US2795658A

US2795658A - Electric circuit controller

Info

Publication number: US2795658A
Application number: US490938A
Authority: US
Inventors: Ward Valley Landon
Original assignee: Magnetic Devices Inc
Current assignee: Magnetic Devices Inc
Priority date: 1955-02-28
Filing date: 1955-02-28
Publication date: 1957-06-11
Anticipated expiration: 1974-06-11

Description

June 11, 1957' v. L. WARD 2,795,658

I ELECTRIC CIRCUIT CONTROLLER Filed Feb. 28, 19 55 3 Sheets-Shae}; 1

INVENTOR SZ/aWe/y Wow 900/10 June 11, 1957 v. 1.. WARD 2,795,658

ELECTRIC CIRCUIT CONTROLLER Filed Feb. 28, 1955 3 Shets-Sheet 2 4 I Wolfe wag June 11, 1957 v. L. WARD 2,795,658

ELECTRIC CIRCUIT CONTROLLER 7 Filed Feb. 28, 1955 3 Sheets-Sheet 3 g7 W466? iiwfiw 90M),

. 36 BY dwfli A 7 4A'ITO VEY United States Patent ELECTRIC CIRCUIT CONTROLLER Valley Landon Ward, Frederick, Md., assignor to Magnetic Devices, Inc., Frederick, Md., a corporation of Maryland Application February 28, 1955, Serial No. 490,938

9 Claims. (Cl. 200-6) My invention relates broadly to electric circuit controllers, and more particularly to an improved quick acting electrical switch system.

One of the objects of my invention is to provide a construction of quick acting electric switch having a high degree of electrical insulation and arranged for reliable and practically noiseless operation.

Another object of my invention is to provide a construction of angularly shiftable electric switch structure operated by a cam-shaped actuator formed from nylon and coacting with a multiplicity of resilient arms supporting electric contacts where the resilient arms are constructed of composite strips of stainless steel and copper with the stainless steel strip establishing contact with the nylon cam-haped actuator for efiecting angular displacement of the arms carrying the contacts for efiecting repeated and successive circuit opening and closing operations in accordance with the angular movement of the nylon cam shaped actuator.

Another object of my invention is to provide a construction of multiple contact switch where the contacts are distributed around an angularly shiftable actuator and wherein the contacts may be readily grouped or rearranged to provide for a variety of electric circuit controlling conditions within extremely small dimensional limits. j

A still further object of my invention is to provide a construction of multiple electric switch which is formed in spaced parallel sections, with the adjacent sections insulated one from another by a substantial barrier of insulation material that extends between the sections and beyond the dimensional limits thereof for forming identification means for the switch contacts assembled in each section.

Other and further objects of my invention reside in the construction and assembly of a multiple section electric switch in which a plurality of independent or different electric circuits may be controlled within an extremely compact space while maintaining a high degree of electrical. insulation between the adjacent sections of the switch for preventing arcing or short-circuiting therebetween; as set forth more fully in the specification hereinafter following by reference to the accompanying drawings, in which:

Fig. 1 is a side elevational view showing one arrangement of a multiple section electric switch embodying my invention;

Fig. 2 is a top plan view of the switch assembly shown in Fig. 1;

Fig. 3 is a bottom view of the switch assembly of Fig. 1;

Fig. 4 is a transverse sectional view taken substantially on line 4-4 of Fig. 1, showing one of the switch sections and the cam-shaped actuator, angularly shiftable resilient contact arms, and the contact terminals in top plan view;

Fig. 5 is a transverse sectional view through one of the switch sections taken substantially on line 5-5 of Fig. l, for example, and showing one extreme position of the cam-shaped actuator;

Patented June 11, 1957 Fig. 6 is a view similar to the view shown in Fig. 5, but illustrating the opposite extreme limit of the camshaped actuator;

Fig. 7 is a vertical sectional view taken through two adjacent sections of the multiple switch of my invention, substantially on line 7-7 of Fig. 4;

Fig. 8 is a view similar to the view shown in Fig. 7, but taken substantially on line 8-8 of Fig. 4;

Fig. 9 is a top plan view showing one of the camshaped actuators constructed from nylon and used in the switch of my invention;

Fig. 10 is a side elevational view of the cam-shaped actuator shown in Fig. 9;

Fig. 11 is a vertical sectional view taken substantially on line 1111 of Fig. 9;

Fig. 12 is a top plan view of a modified form of contact carrying arm which may be employed in the structure of my invention;

Fig. 13 is a sectional view taken substantially on line 13-13 of Fig. 12;

Fig. 14 is a top plan view showing one of the terminal strips and contact supporting arms employed in the form of my invention illustrated in Figs. 1-8 and 1648;

Fig. 15 is a vertical sectional view taken on line 15--15 of Fig. 14;

Fig. 16 is a view illustrating the manner in which the contacts carried by the resilient arms establish line contact with the side of the contact pin carried by the terminal strip in the switch assembly;

Fig. 17 is a view similar to the view shown in Fig. 16 but illustrating the contact position alternate to the contact position shown in Fig. 16; and

Fig. 18 is a view taken on line 18-18 and illustrating more clearly the lineal connection between the contact carried by the resilient arm and the pin carried by the contact terminal in the switch assembly of my invention.

My invention is directed to a compact construction of electric switch to which angular movement may be imparted in alternate opposite directions for controlling the opening or closing of a multiplicity of contacts in a variety of circuit permutations and combinations.

The switch or" my invention is assembled from a multiplicity of switch sections or Wafers having recesses for mounting terminal strips in selected positions therein for providing supports for resilient arms arranged in the path of an angularly rockable cam-shaped actuator. The

resilient arms each carry electric contacts aligned with respect to terminal pins supported by certain of the terminal strips. The contacts on the resilient arms establish line contact with the sides of the terminal pins under control of the cam actuator which is mounted to rock or oscillate angularly in a position substantially coplanar with the switch section and all of the components therein, that is, the resilient arms, the contacts carried thereby, the terminal pins supported in alignment therewith and the cam acuator. Thus a muliple number of circuits may be controlled within small dimensional limits and each switch section substantially insulated from an adjacent switch section by a barrier of insulation material which extends throughout the distance from a position adjacent the operating shaft of the switch and between the contacts associated with each switch section to a position beyond the switch sections where the barriers serve as identification or indicator means for the contacts carried by the switch sections. Any number of switch sections may be superimposed one with respect to another, and operated by a common angularly shiftable shaft which extends through all of the sections with the barriers disposed therebetween. The resilient arms which carry the contacts are of laminated construction. In the preferred form of my invention the arms are formed by a strip of .003" stainless steel and a strip of .009" copper,

where the stainless steel provides the wiping surface against which the cam actuator, which is formed from nylon, operates, while electrical conductivity to the contact carried by the strip is assured through the copper strips of the composite lamination.

In am'odified form of my invention I provide a laminated structure for the contact supporting strip which has a center which is formed from a central copper strip with a thin stainless steel strip on each side thereof.

This arrangement provides for a high degree of current a carrying capacity with good electircal conductivity at the same time that the contact arm is assured of a practically unlimited life due to the wiping of the nylon cam against the surface oftbe stainless steel strip of the con tact arm, while resiliency is imparted to the contact arm a through the stainless steel strips.

, Referring to the drawings in more detail, the operating shaft for the multiple switch of my invention isrepresented at 1 as having a polygonally-shaped transverse section and extending through the casing of the switch and terminating in a polygonally-shaped end section at 2 which is gripped by a shaft actuator 3 adapted to angularly shift or oscillate the shaft 1 about its central axis. The shaft 1 terminates in a shoulder 4 with respect to which the sections of the switch are assembled. l have shown the switch assembly as comprising the bottom section 5 and the multiplicity of superimposed switch or wafer sections represented for example by the

adjacent sections

8 and 9. A top section 6 completes the multiple switch assembly and there are fastening bolts 7 extending through the superimposed sections, the bolts being secured at their opposite ends by cap screws 7a and 7b as shown.

The several switch sections are assembled in accordance with the requirements of the electrical circuits to be controlled and I have

detailed switch sections

8 and 9 as illustrative of all of the switch sections. The arrangement of the contacts in the several switch sections may be selected in accordance with the requirements of each electrical circuit to be controlled as the positioning of the switch arms with respect to the cam actuator determines the time period at which the contact may be made or broken. To faciliate explanation of the invention, I have detailed the

adjacent switch sections

8 and 9 in Figs. 4-8 and have oriented the switch sections to clarify explanation, of the assembly. In Fig. 4 I have illustrated the switch section 8 as having

terminals

10, 11, 12, 14, and 16 consisting of radially extending strips fitting in radially disposed grooves in the ring of insulation material constituting the circular switch section 8. These terminals may be molded directly in the switch section 8 or they may be removably assembled in complementary radial grooves formed in the ring of switch section 8 to allow for interchange in position of the terminals as will be hereinafter explained in more detail. The terminals 1016 serve as supports for the

resilient arms

18, 19, and 21, as shown. These resilient arms are laminated and comprise a strip of stainless steel 22 and an adjacent strip of copper 23 and carry on the end thereof a contact which, in the case of arm 18, is designated at 18a and with respect to

arms

19, 20 and 21, is shown at 18a, 19a, 20a and 21a.

Each

terminal

10, 11, 12, 14, 15 and 16 includes a

securing instruck lug

10a, 11a, 12a, 14a, 15a and 16a which facilitates the molding of the terminal into the insulation material of the ring constituting the switch section 8. Each terminal includes a terminal screw 1%, 11b, 12b, 14b, 15b and 16b by which electrical connec tion is made to each resilient arm or contact associated with the respective terminals. Each connector supports a depending

10c, 11c, 12c, 14c, 15c and 160 disposed on axes which are parallel to the central axis of shaft 1, and which serve either as supports for the resilient arms or as contacts with respect to which the arms coact.

Th Shaft 1 s o n s PI d ith a um? some! section 25 which enables the cam-shaped actuators represented at 26 to be assembled in properly aligned positions on the shaft 1. Each cam-shaped actuator is constructed from nylon pressed to shape under high pressure to form the actuator cam. The actuator cams 26 in the multiple switch assembly are all uniform in construction and are provided with a central aperture 28 corresponding in transverse section to the transverse section of shaft 1 including the cutoff 29 in aperture 28. In order to provide for the proper sequential operation of the contacts under conditions of oscillatory movement of the shaft 1, the aperture 28 is oriented to a position displaced from longitudinal alignment with the longitudinal axis of the actuating cam, as shown more clearly in Figs. 46 and Fig. 9. For most efficien-t use of available space I orient the transverse axis of the aperture 28, l1% with respect to the transverse axis of the cam-shaped actuator 26. This arrangement assures assembly of the cam-shaped actuator on the shaft 1 with the cutoff portion 29 thereof coacting with the cutoff portion 25 of shaft 1 so that the cam-shaped actuator exends at an angle with respect to the sides of the polygonally-shaped shaft 1 and in a position to actuate or displace arms 1821 by very slight angular or oscillatory movement of shaft 1.

Each of the cam actuators has embedded therein a circular identification ring 27 which defines the peripheral edge of the circular projection 30 on each end of the cam actuator.

The projections 30 at each end of adjacent cam-shaped actuators extend toward each other and into the central aperture 32 in the barrier and identification ring 31 which separates the switch sections one from the other. The depth of the projections or bosses 30 is slightly greater than one-half the thickness of the barrier 31 so that the cam-shaped actuators 26 each move without appreciable frictional contact with the surface of the barrier 31. The barrier also projects beyond the peripheral edges of the adjacent switch sections preventing are over or shortcircuit between the circuit terminals of the several switch sections and also providing space 33 for identification markings of the aligned circuit terminals at screws 10b- 16b. The combination barrier and identification ring 31 may be formed from melamine glass having a high degree of insulation which resists electrical breakdown by so extending the length of the leakage path that breakdown is minimized. For example, breakdown cannot occur until the leakage path has extended all the way across the outside of one face of the barrier 31, down the edge and back again across the opposite face before breakdown can occur. The cam-shaped actuators 26 are assembled with respect to the barriers 31 by aligning the identification ring 27 of the cam-shaped actuator 26 with the inner peripheral edge 32 of the barrier 31 providing a substantially insulated box-like spaced housing for the operating contacts constituting the switch. Each of the switch sections is formed by a toroidally-shaped housing of insulation material into which the terminals 10-16 may be either removably or permanently mounted in alignment with the plane of the edge of the casing. This toroidallyshaped housing constitutes a ring surrounding the contact pins and the resilient arms and contacts constituting the interior working parts of the switch.

The stroke of each of the

arms

18, 19, 20 and 21 is extremely short and the displacement of the

contacts

18a, 19a, 20a and 21a with respect to the coacting pins10c and is less than so that the speed of operation is quite high. The contacts are driven open by the cam 26 actuating against the stainless steel surface 22 of

arms

19 and 21, as shown in Figs. 5 and 6, and make the contact by the spring pressure of the moving arms. Thus the switch may fail safe instead of closed. These contacts can be arranged to break before make or can be made to make before break by permanently forming the moving arms accordingly. The contact arms which are made from .003" stainless steel on one side, and .009" thick copper on the other side and the two pieces welded to gether throughout their entire length provide resistance of but .003 ohm. With the cams 26 made of nylon and moving or siding against the stainless steel 22 instead of Phosphor bronze, or copper bearing material, the cam lasts many times longer. In actual tests I have noted operations of such an arm 552,000 times showing about the same amount of wear as is obtained by running the Phosphor bronze arm one hundred thousand times. The cam 26 when made of molded nylon is fungus proof and does not pick up particles of metal from the stainless steel strip 22. v V a The pins 100-160 are all uniform in arrangement with respect to the terminals -16 so that they may be used selectively as support for the arms 1821 or as contacts in arranging different permutations and combinations of electrical switching circuits so that the switches may operate normally open or normally closed in singlepole, single-throw or single-pole, double-throw arrangements. The switch arms 18-21 or switch arm 34, each includes convolutions at one end thereof forming a sleeve which may be resiliently fitted over the selected pin and secured in position thereon.

In lieu of the stainless steel-copper laminated arms I may employ arms 34 of the type shown in Figs. 12 and 13 where a conductive center 35 of copper is provided with stainless steel layers 36 and 37 on each side thereof and supporting a contact 34a. This dual coated material facilitates the fabrication of the arms as both outside surfaces are stainless steel and contact with the nylon cam 26 without regard to the manner of forming the arms.

Figs. 16-18 show the advantages secured by the lineal connection obtained between the sides of pin 10c and the

contacts

18a and 19a. The

pins

10c and 140 are silver and are stationary making contact with the moving

arms

18 and 19 and 20 and 21, having silver contacts 181:, 19a, 20a and 21a riveted to the ends of copper spring strips 22. The face of the moving contact is flat and when it makes contact with the

round silver pin

10c or 14c, instead of making point contact, it makes line contact the length of the diameter of the moving contact. The spring being resilient, the arms will twist slightly so as to make up for any misalignment which may occur due to moving variations. This practically guarantees line contact in assembly.

In showing the adjacent switch section at 9 in a position immediately adjacent section 8, I have designated the switch components already described in connection with switch section 8 by corresponding reference characters to which prime marks have been added.

The switch system of my invention has proven highly satisfactory in operation and while I have described my invention in one of its preferred embodiments I realize that modifications may be made, and I desire that it be understood that no limitations upon my invention are intended other than may be imposed by the scope of the appended claims.

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

1. In a multiple electric switch, a plurality of switch sections formed by toroidal-shaped housings of insulation material superimposed one adjacent another, an angularly movable shaft member extending axially through said switch sections, a cam-shaped actuator individual to each of said switch sections and mounted on said shaft member, terminals supported by said switch sections and extending radially into the interiors of said housings, pins supported by said terminals and extending on axes parallel with the axis of said shaft member and spaced from the internal walls of said housings and out of the path of movement of said cam-shaped actuator, certain of said pins constituting cylindrical side wiping contact surfaces, yieldable switch arms supported by others of said pins, said switch arms extending in the path of movement of the associated cam-shaped actuator for movement by said actuator, contacts carried by the ends of said arms and movable into contacting relation with said cylindrical side wiping contact surfaces of said aforementioned pins, and means extending between said toroidal-shaped housings and forming a barrier of insulation material for electrical ly insulating the terminals, pins, contacts, cylindrical side wiping contact surfaces, and switch arms of one of said toroidal-shaped housings from the terminals, pins, contacts, cylindrical side wiping contact surfaces, and switch arms of an adjacent toroidal-shaped housing;

2. In a multiple electric switch as set forth in claim 1 in which said means are constituted by fiat circular plates of insulation material which extend from a position adjacent said cam-shaped actuators to a position beyond said switch sections for establishing an extended insulation path beyond :both the inner and outer limits of said terminals, pins, contacts, cylindrical side wiping contact surfaces and switch arms of each of said toroidal-shaped housings, adjacent cam-shaped actuators including shoulders thereon which enter a central aperture in the barrier between said actuators from opposite sides thereof with said actuators overlapping opposite sides of the inner peripheral portion of the barrier.

3. A multiple electric switch as set forth in claim 1 in which said means are constituted by plates of melamine glass extending from a position adjacent said shaft to a position beyond the peripheral limits of said toroidalshaped housings.

4. A multiple electric switch as set forth in claim 1 in which each of said cam-shaped actuators includes an annular projection on each end thereof with the projections on the ends of adjacent cam-shaped actuators directed toward each other in end-to-end abutting relation providing an annular groove between the surfaces of said cam-shaped actuators and wherein said barriers of insulation material are centrally apertured circular plates having the inner peripheries extending between the camshaped actuators and into the grooves between said camshaped actuators, the outer peripheries of said plates extending beyond the outer peripheries of said toroidalshaped housings.

5. In a multiple circuit switch, a substantially toroidally-shaped casing of insulation material, a multiplicity of radially disposed terminals supported by said casing and extending inwardly to positions within said casing, pins supported on the ends of each of said terminals and extending on lineal axes in directions substantially parallel and spaced from the interior wall of said casing, certain of said pins carrying resilient arms terminating in contacts and others of said pins constituting cylindrical contacts coacting with the aforesaid contacts, a cam-shaped actuator of insulation material disposed centrally within said casing and movable in a path centrally within the axes of said pins and selectively engageable with said resilient arms for displacing said arms for modifying the contacting relationship of the contacts carried thereby with respect to the pins constituting said cylindrical contacts, and means for rotating said cam-shaped actuator for effecting displacement of said arms.

6. A multiple circuit switch as set forth in claim 5 in which said cam-shaped actuator of insulation material is formed from nylon.

7. A multiple circuit switch as set forth in claim 5 in which said resilient arms are formed compositely from flat strips of stainless steel and copper superimposed in layers with respect to each other, said strips being disposed in planes extending in directions coincident with the direction of the axis of said cam-shaped actuator with said stainless steel strip in immediate contact with the surface of said cam-shaped actuator of insulation material.

8. A multiple circuit switch as set forth in claim 5 in.

7 strip coplanar and extending in .planeswhich are ,coin: cident in direction with the axis of said cam-shaped actuator with the stainless steel strips disposed in wiping rela.- tion to the operating surface of the nylon cam actuator. 9. A multiple circuit switch as set forth in claim 5 in which said resilient arms are shaped at the terminating ends thereof to present the contacts carried thereby in lineal tangential contact with the opposite sides of the pins constituting the cylindrical contacts of said switch at positions that are substantially diametrical through said cylindrical contacts and through the centers of the contacts on said resilient arms.

7 Ref renc s C t d in the file f thi pat n UNITED STATES PATENTS Yeske Dec, 5, Kimball Dec. 17; v Glogau May 18, Johnson June 24, Rowe Mar. 29, Coliz May 31,

FOREIGN PATENTS Germany May 18,

Great Britain Mar. 1,