US3402275A - Cam actuated multiple switch - Google Patents

Description

Sept. 17, 1968 M. C.PODGORSK| ETAL 3,402,275

CAM ACTUATED MULTIPLE SWITCH Filed Oct. 31, 1966 FIG, 1

IN W. N TOPS Maiihew C. Podgorslei and Guy Mfarrell United States Patent 3,402,275 CAM ACTUATED MULTIPLE SWITCH Matthew C. Podgorski, Wood Dale, and Guy M. Farrell, Elmhurst, Ill., assignors to F & F Enterprises, Inc., Chicago, III., a corporation of Illinois Filed Oct. 31, 1966, Ser. No. 590,644 14 Claims. (Cl. 200-153) ABSTRACT OF THE DISCLOSURE lowers.

Specification This invention relates to an improved switch construction. The invention is specifically directed to a multiple switch construction which is adapted to be actuated by cam means for achieving various combinations of switch conditions.

There are obviously innumerable instances where multiple switch arrangements must be utilized in various constructions. It is relatively simple to incorporate such switch arrangements in most constructions since the respective switches can be located in a circuit and individual actuating means can be provided for the several switches. Obviously, any variety of switch conditions can be achieved by selectively operating the respective actuating means.

Where multiple switch arrangements are to be employed in certain constructions, however, obvious techniques for incorporating the switches cannot be utilized. For example, size limitations are often met by designers, and it is, therefore, necessary to provide switches which are quite compact.

In many instances, it is also necessary to provide multiple switch arrangements which can be actuated without undue delay. In such cases, it would be completely impractical to require an operator to operate each of several switches individually in order to bring about a desired combination of open and closed contacts. This is particularly true where the particular circuit including the switches contemplates a relatively large variety of difierent switch combinations.

It is a general object of this invention to provide an improved multiple switch arrangement which is characterized by a unique operating structure whereby the switch arrangement can be advantageously employed in a variety of different circuits.

It is a more particular object of this invention to provide a multiple switch construction which is designed so that the construction can be efficiently manufactured, operated and maintained even though the switch may be produced in an extremely small size.

It is a still further object of this invention to provide a switch construction which embodies unique operating characteristics whereby the switch can be actuated through the use of a simple control mechanism while still achieving a large variety of different combinations of switch conditions.

These and other objects of this invention will appear hereinafter and for purposes of illustration, but not of limitation, specific embodiments of the invention are shown in the accompanying drawings in which:

FIGURE 1 is a cross-sectional view of the construction taken about the line 11 of FIGURE 2;

FIGURE 2 is a cross-sectional view of the construction taken about the line 22 of FIGURE 1;

FIGURE 3 is a cross-sectional view of the construction taken about the line 33 of FIGURE 1; and,

FIGURE 4 is a cross-sectional view illustrating an alternative form of the invention.

The construction of this invention generally consists of a mounting means which supports a plurality of movable contact elements. These contact elements form a plurality of separate switches and each of the switches is adapted to be actuated more or less independently of other switches whereby the switches are capable of producing a variety of difierent combinations of switch conditions in an electrical circuit.

The actuating means for the switches comprise cam followers associated with the contact elements. Cam tracks are defined by an actuating member, and the movements of the actuating member result in corresponding movement of the cam followers thereby changing the condition of the several switches. A plurality of cam track and cam follower combinations are preferably associated with a single actuating member whereby all of the desired switch conditions can be achieved through operation of the single actuating members.

The accompanying drawing illustrates a switch construction 10 incorporating the features of the instant invention. The construction includes a mounting bracket 12 in the form of a U-shaped member having opposed side walls 14 and a base 16. Flanges 18 are provided for securing the mounting member to an appropriate base.

A plurality of switches 20 are secured in the construction by means of bolts 22 although suitable rivets or eyelets may be used for this purpose. The switches include leaf spring portions 24 having contact elements 26 secured at their free ends. Insulating members 28 divide the respective leaf springs and conventional means can be employed for including the leaf springs in an electrical circuit.

Each of the switches illustrated comprises a single pole, double throw arrangement including three leaf springs. The central leaf spring element of each switch includes an extending portion 30 having cam follower elements 32 secured thereto.

The cam follower elements each fit within grooves 34 defined by cam block 36. The cam block comprises a member of rectangular cross section fitted between the side walls 14 adjacent the base 16, An extension 38 formed integrally with the cam block extends through a slot 40 defined by the mounting means. As illustrated in FIGURE 2, the extension 38 provides a means for sliding the cam block back and forth within the confines defined by the mounting means. Roller bearing elements 42 serve to retain the cam block in its position adjacent the base 16. These roller bearing elements also facilitate movement of the cam block between its various operating positions. It will be obvious that a suitable support plate could be used in place of these bearing elements.

The cam follower elements 32 include a base portion secured to the leaf springs 24, and a pin portion 43 which actually fits into the grooves 34. The base portion of the cam followers is situated between the two central bearing elements 42 whereby the cam follower is restrained against any movement in the direction of movement of the cam block 36.

As best shown in FIGURE 3, the grooves 34 define a non-linear path from one end of the cam block to the other. Accordingly, as the cam block is moved, the cam follower pins 43 will be shifted in accordance with the design of the grooves. The shifting action results in movement of the central leaf members of each switch. The condition of each switch is, therefore, determined by the configuration of the grooves 34 and by the position of the cam block. Obviously, each switch can be closed in one position or another or the switches can be held in the open position. With the very basic arrangement illus trated, there are a large number of combinations of circuit conditions available. As the cam block is moved from one position to another, the several switch combinations can be selected.

As indicated, the drawing illustrates a relatively simple application of the instant invention. The cam block 36 is adapted to be held in either of three positions which are determined by the provision of detent openings 44 defined by the side walls 14. Balls 46 are carried by the cam block so that the operator can readily determine when the block is in a desired position while permitting easy movement of the block to a different position. A spring 48 normally urges the balls 46 into the openings 48 or against the side walls 14.

The modification illustrated in FIGURE 4 comprises essentially the same structural arrangement previously discussed. A cam block 50 is adapted to be mounted in a suitable housing, and cam followers 52 are adapted to actuate switches in response to cam movements. Bearing pins 54 provide support for the cam block 50.

This modification includes a torsion spring element 56 which has one end secured to a rod 58 which is fixed to the housing of the switch. A central loop of the torsion spring is wrapped around a bearing pin 54. The other end of the spring is received in a slot 60 defined by the cam block 50.

The spring is adapted to give when the shoulder 62 of the cam block presses against the spring. Due to the design of the spring, the cam block will be constantly urged back and, accordingly, if the pushing force on the cam block is removed, the switch will reset. This arrangement is desirable where only a momentary closure of switch contacts is required.

It will be noted that the slot 60 defines an extension 64 beyond the shoulder 62 If the force applied to the cam block is sufficient, the spring 56 will be received in this extension, and at this point, the spring will not act to force the cam block back. The cam block must be retracted by force until the spring engages the shoulder 62 at which time the spring action will come into play.

It will be appreciated that the illustrated arrangement merely provides one possible application of the instant invention. A wide variety of'switch designs could be employed in association with the operating structure of the invention whereby the simple movement of a cam block will provide for a complete change in an electrical circuit. The number of different combinations which can be achieved by the cam block movement is only limited by the ability of the switches to assume different positions. Thus, a much greater number of stopping positions for the cam block are contemplated and, of course, the grooves 34 can assume much more complex configurations.

The advantages of the switch construction of this invention are many. The design of the construction is quite basic in nature and there is no great difficulty encountered when manufacturing and assembling. The switch actuating means can be easily operated by finger controls although automatic operation of the actuating means is contemplated. Visual indications can be formed on the exterior surface of the base 16 to assist an operator in determining the switch condition which will be achieved when the actuating means is in a certain position.

It will be understood that various changes and modifications may be made in the above described construction which provide the characteristics of this invention without departing from the spirit thereof particularly as defined in the following claims.

That which is claimed is:

1. A switch construction comprising mounting means, a plurality of movable contact elements supported by said mounting means, said contact elements forming a plurality of separate switches, switch actuating means operatively connected to said contact elements, cam followers associated with said switch actuating means, and cam means defining cam tracks engaged by said cam followers whereby relative movement of said cam means and said cam followers results in simultaneous movement of each of said cam followers to thereby effect opening and closing of said separate switches, said cam tracks defining irregular paths with at least some paths differing from others for achieving a plurality of different combinations of switch conditions, said cam means having a plurality of distinct positions relative to said cam followers with each position providing a particular combination of switch conditions, and including means for determining the position of said cam means.

2. A construction in accordance with claim 1 wherein said cam means comprises a block reciprocally held by said mounting means and including means connected to an exterior surface of the block for imparting movement to the block.

3. A construtcion in accordance with claim 2 including bearing element supporting the block within the housing and facilitating movement of the block.

4. A construction in accordance with claim 2 wherein said cam tracks comprise grooves defined on an interior surface of said block and extending in side by side relationship in a direction generally corresponding to the direction of movement of the block, and wherein said cam followers comprise pins extending within said grooves.

5. A construction in accordance with claim 1 wherein said contact elements are mounted on leaf springs, and including extensions associated with at least some of said leaf springs, said cam followers being attached to said extensions.

6. A construction in accordance with claim 5 wherein said mounting means comprises a U-shaped member, said leaf springs being confined at one end between the op posed arms of said U-shaped member with the free ends of said leaf springs extending toward the base of said U-shaped member, said cam means being reciprocally held adjacent said base.

7. A construction in accordance with claim 1 wherein the means for determining the position of said cam means comprise detent means defined between the cam means and the adjacent mounting structure, said detent means releasibly holding the cam means in said distinct positions.

8. A construction in accordance with claim 1 wherein said means for determining the position of said cam means comprise visible indications located on the exterior surface of the construction.

9. A switch construction comprising mounting means, a plurality of movable contact elements supported by said mounting means, said contact element forming a plurality of separate switches, switch actuating means operatively connected to said contact elements, cam followers associated with said switch actuating means, and cam means defining cam tracks engaged by said cam followers whereby movement of said cam means results in simultaneous movement of each of said cam followers to thereby effect opening and closing of said separate switches for achieving a plurality of combinations of switch conditions, said cam means comprising a block reciprocally held by said mounting means and including means connected to an exterior surface of the block for imparting movement to the block, said cam tracks comprising grooves defined on an interior surface of said block and extending in side by side relationship in a direction generally corresponding to the direction of movement of the block, and wherein said cam followers comprise pins extending within said grooves, and including means for restraining said pins against movement along the length of said grooves.

10. A switch construction comprising mounting means, a plurality of movable contact elements supported by said mounting means, said contact elements forming a plurality of separate switches, switch actuating means operatively connected to said contact elements, cam followers associated with said switch actuating means, and cam means defining cam tracks engaged by said cam followers whereby movement of said cam means results in simultaneous movement of each of said cam followers to thereby eiTect opening and closing of said separate switches for achieving a plurality of combinations of switch conditions, said contact elements being mounted on leaf springs, extensions associated with at least some of said leaf springs, said cam followers being attached to said extensions, and wherein said mounting means comprises a U-shaped member, said leaf springs being confined at one end between the opposed arms of said U-shaped member with the free ends of said leaf springs extending toward the base of said U-shaped member, said cam means being reciprocally held adjacent said base, and including bearing elements rotatably mounted between said opposed arms in spaced apart relationship with respect to said base, said earn means being supported by said bearing elements, and wherein said free ends of said leaf springs are restrained by said bearing elements against movement along the length of said grooves.

11. A switch construction comprising mounting means, a plurality of movable contact elements supported by said mounting means, said contact elements forming a plurality of separate switches, switch actuating means operatively connected to said contact elements, cam followers associatd with said switch actuating means, and cam means defining cam tracks engaged by said cam followers whereby movement of said cam means results in simultaneous movement of each of said cam followers to thereby effect opening and closing of said separate switches for achieving a plurality of combinations of switch conditions, and including spring means associated with said mounting means and adapted to be engaged by said cam means whereby the spring means is adapted to yield in response to engagement by the cam means to achieve a desired switch condition and whereby the spring means is adapted to urge the cam means to a retracted position.

12. A construction in accordance with claim 10 wherein said bearing elements comprise cylinders positioned transversely to the direction of said cam tracks.

13. A construction in accordance with claim 11 wherein said cam means comprises a block reciprocally held by said mounting means, and wherein said spring means is adapted to be received within a slot defined by said block.

14. A construction in accordance with claim 13 wherein said slot defines an abutment for engagement with said spring, and including an extension of said slot beyond said abutment whereby said block is adapted to override said spring.

References Cited UNITED STATES PATENTS 2,816,977 12/1957 Kramer 200l53.l2 XR 3,249,725 5/1966 Hutt et al. ZOO-153.12

ROBERT K. SCHAEFER, Primary Examiner.

H. BURKS, Assistant Examiner.

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