US3792219A

US3792219A - Pushbutton switch with coil spring movable content wedgingly engageable with stationary housing contact

Info

Publication number: US3792219A
Application number: US00267891A
Authority: US
Inventors: P Rowley
Original assignee: Robertshaw Controls Co
Current assignee: Allen Bradley Co LLC; Air Maze Corp; Fleet National Bank
Priority date: 1972-06-30
Filing date: 1972-06-30
Publication date: 1974-02-12
Anticipated expiration: 1991-02-12

Abstract

An electrical switch construction having a housing and a movable plunger carried by the housing. A compression spring is carried by the housing and is engageable with the plunger, the spring when in one operative position being in wedged relation with the housing to provide an electrical circuit through the spring to the housing at the wedging engagement therebetween. The spring, housing and plunger are so constructed and arranged that when the plunger is moved to a certain position relative to the housing, the spring is moved out of its wedging relation with the housing to break the electrical circuit therethrough.

Description

United States Patent [191 Rowley [11] 3,792,219 1451 Feb. 12, 1974 PUSHBUTTON SWITCH WITH COIL SPRING MOVABLE CONTENT WEDGINGLY ENGAGEABLE WITH ST TIONARY HOU ING CONTACT [75] Inventor: Paul M. Rowley, Bexley, Ohio [73] Assignee: Robertshaw Controls Company,

Richmond, Va.

[22] Filed: June 30, I972 [21] Appl. No: 267,891

[52 US. CI.... 200/159 R, 200/166 BA [51] Int. Cl. ..I-I01h 13/52, I-lOlh 1/18 [58] Field of Search... 200/159 R, 166 BA, 153 M, I 1 200/153 LA [56] References Cited UNITED STATESJPATENTS' 959,435 5/1910 -Thoms0n ..'..,..'..'200/I66 BA 2,444,552 7/1948 Brantingson.... 200/166 BA x 2,907,852 1 10/1959 Long et a1. 200/159 R 1,859,981 5/1932 'Norviel 200/159R 2,572,335 Hafke 200/159 R X 3,211,872 10/1965 Baer, .0 200/166 BA X FOREIGN PATENTS OR APPLICATIONS 7/1960 Italy 200/159 R Primary Examiner-Robert K. Schaefer Assistant Examiner-Robert A. Vanderhye Attorney, Agent, or Firm-James T. Candor 57 ABSTRACT An electrical switch construction having a housing and a movable plunger Carried by the housing. A compression spring is carried by the housing and is engageable with the plunger, the spring when :in one operative position being in wedged relation ,with the housing to provide an electrical circuit through the spring to the housing at the wedging engagement therebetween.

The spring, housing and plunger are so constructed and arranged that when the plunger is moved to a certain position relative to the housing, the spring is moved out of its wedging relation with the housing to break the electrical circuit therethrough.

20 Claims, Drawing Figures PUSHBUTTON SWITCH WITH COIL SPRING MOVABLE CONTENT WEDGINGLY ENGAGEABLE WITH STATIONARY HOUSING CONTACT This invention relates to an improved electrical switch construction as well as to an electrical control system utilizing such electrical switch construction.

Push button operated electrical switch constructions are well known in the art for various uses such as an interlock switch with a gasoline engine wherein a lead wire is to be connected to a grounded housing of the switch construction when the push button thereof is released. For example, releasing of the push button of the electrical switch construction can short out the ignition of the gasoline engine in emergencies. Another typical application of such a push button switch construction is an automotive application wherein a dome light or warning light is operated when a door is open and thus releases the push' button of the electrical switch construction.

Accordingly, it is a feature of this invention to provide an improved electrical switch construction of the above push button type.

In particular, one embodiment of this invention provides an electrical switch construction having a housing means and a movable plunger means carried by the housing means. A compression spring means is carried by the housing means and is engageable with the plunger means. The spring means when in one operative position is in a wedged relation with the housing means to provide an electrical circuit through the spring means to the housing means at the wedging engagement therebetween. The spring means, housing means and plunger means are so constructed and arranged that when the plunger means has been moved to a certain position relativeto the housing means, the spring means is moved out of its wedging relation to break the electrical circuit through the electrical switch construction.

Accordingly, it is an object of this invention to provide an improved electrical switch construction having one or more of the novel features set forth above or hereinafter shown or described.

Another object of this invention is to provide an electrical control system utilizing such electrical switch construction.

Other objects, uses and advantages of this invention are apparent from a reading of this description which proceeds with reference to the accompanying drawings forming a part thereof and wherein:

FIG. 1 is a cross-sectional view of the improved electrical switch construction of this invention and schematically illustrates the electrical control system utilizing such electrical switch construction.

FIG. 2 is a view similar to FIG. 1 and illustrates the push button electrical switch construction moved to another operative position thereof.

FIG. 3 is an exploded perspective view of the various parts of the electrical switch construction of this inven tion.

While the various features of this invention are hereinafter illustrated and described as being particularly adaptable to provide an electrical switch construction which is adapted to complete an electrical circuit through a grounded housing of the electrical switch construction, it is to be understood that the various feathat is generally indicated by the reference numeral 11 and comprising an electrical power source 12 having one side 9 grounded by a lead 8 and the other side 13 interconnected by a lead 14 to one side 15 of a control device 16 having the other side 17 thereof interconnected by a lead 18 to one side 19 of the electrical switch construction 10 while the other side 20 of the electrical switch construction 10 is interconnected by a lead 21 to ground.

Thus, it can be seen that when the electrical switch construction 10 completes the electrical circuit between the

sides

19 and 20 thereof in a manner hereinafter set forth, an electrical circuit is completed so that the electrical power source 12 can operate the control device 16. However, when the electrical switch construction 10 is operated to break the electrical circuit between the

sides

19 and 20 thereof, the electrical power source 12 can no longer operate the device 16.

The electrical switch construction 10 of this invention comprises a housing means that is generally indicated by the reference numeral 22 in FIG. 1 and comprises an electrically conductive tubular part 23 having opposed

ends

24 and 25 that are respectively interrupted by a stepped passage 26 passing completely throughthe housing member 23. The stepped passage 26 forms a first cylindrical portion 27 at the end 24 of the member 23, an annular shoulder 28, a reduced cylindrical portion 29, an annular shoulder 30, a larger diameter cylindrical portion 31, a frusto-conical portion 32 having its smaller base 33 interconnected to the cylindricalportion 31 and its larger base 34 interconnected to a larger diameter cylindrical portion 35, an annular shoulder 36 and a larger diameter cylindrical portion 37 at the end 25 of the housing member 23.

A second housing part 38 is disposed in the end 25 of the housing part 23 to close the end 25 and is formed of electrically non-conductive material, such as plastic or the like. The housing part 38 includes a first cylindrical portion 39 telescoped within the cylindrical part 35 of the passage 26 of the housing part 23 and has a larger cylindrical part 49 defining a shoulder 41 therewith that is adapted to abut against the shoulder 36 of the housing part 23. If desired, a sealing gasket 72 can be disposed between the shoulder means 41 and 36 to seal the housing part 38 within the housing part 23 as illustrated with the larger cylindrical part 40 of the housing part 38 being telescoped within the cylindrical part 37 of the passage 26 of the housing part 23.

After the housing part 38 has been assembled with the housing part 23 as illustrated in FIG. 1, the end 25 of the housing part 23 can be turned over as illustrated to secure the housing part 38 in place.

A passage 42 passes through the housing part 38 and defines a first cylindrical part 43, an annular shoulder 44, a reduced cylindrical part 45, an annular shoulder 46 and a large diameter cylindrical part 47. A metallic eyelet 48 is disposed in the passage 45 as illustrated so that one flanged end 49 of the eyelet 48 is disposed against the annular shoulder 44 of the housing part 38 while the other flanged end 50 of the eyelet 48 is disposed against the shoulder 46.

The lead 18 can comprise an electrical cable 51 having the electrical strands or wire 52 thereof passing through the eyelet 48 as illustrated and be soldered or otherwise electrically fastened thereto so that the insu- Iation 53 of the cable 51 will be received within the cylindrical part 43 of the housing part 38 and be sealed therein by a suitable plastic sealing material 74 as illustrated whereby the conductive part 52 of the cable 51 is electrically insulated by the housing part 38 from the conductive and grounded housing part 23.

A coiled compression spring 54, formed of metal or other conductive material, is disposed within the housing part 23 and has opposed

ends

55 and 56, the end 55 being fastened to the flanged end 50 of the eyelet 48 so as to be fixed from movement within the housing means 22 while being in electrically conductive relation with the lead 18 as illustrated. If desired, the conductive strands or wire 52 of the cable 51 can also be soldered directly within the end 55 of the spring 54.

The compression spring 54 is so constructed and arranged that the same has a frusto-conical configuration with the end 56 being the larger base thereof and being of such a size that when the same is received within the cylindrical part 31 of the passage 26 of the housingpart 23 as illustrated in FIG. 1, the first two or three turns of the spring 54 at the end 56 is radilly inwardly compressed by thecylindrical part 31 of the housing 23 so as to be disposed in wedging relation therewith and, thus, in good electrical contact with the housing part 23 at the cylindrical part 31 thereof. However, when the end 56 of the spring 54 is moved from the cylindrical part 31. of the passage part 26 of the housing 23 to within the larger cylindrical part 35 of the passage 26 as illustrated in FIG. 2 in the manner hereinafter described, it can be seen that the wedging relation of the end 56 of the spring 54 with the housing part 23 is terminated so that the end 56 of the spring 54 is no longer in electrical contact with the housing part 22 whereby the circuit between the sides 19 and of the electrical switch construction .1 l is broken for a purpose hereinafter set forth.

A push button or plunger means 57 is carried by the housing means 22 and has a cylindrical part 58 passing through the cylindrical part 29 of the passage 26 of the housing part 23 and out through the open end 24 thereof to define an end 59 which can be engaged to push the push button 57 from the position illustrated in FIG. 1 to the position illustrated in FIG. 2 in opposition to force of the spring 54 to open the electrical circuit through the switch construction 10.

In particular, the push button 57 has a disk-like end part 60 at the right-hand end thereof which is adapted to be received within the cylindrical part 31 of the passage 26 of the housing part 23 and abut against the shoulder as illustrated in FIG. 1 by the force of the compression spring 54 acting against the side 61 of the flange or disk 60 of the push button 57 so as to limit outward movement of the push button 57 relative to the housing means 22. If desired, a cylindrical part 62 can extend from the flange part 60 of the push button 57 to be received within the end 56 of the spring 54 to provide a guide means therefor as will be apparent hereinafter.

If desired, a suitable O-ring seal 63 can be disposed within the cylindrical part 27 of the passage 26 in the housing part 23-and about the cylindrical part 58 of the push button 57 to seal the passage 26 from the exterior thereof at the shoulder means 28. A cylindrical bearing means 64 can also be disposed in the end 24 of the housing part 23 to hold the O-ring 63 in place and also to guide axial movement of the push button 57 relative thereto.

The housing part 23 can have an exteriorly threaded portion 65 at the end 24 thereof to permit fastening of the housing means 22 to the desired structure, such as to a door frame or the like so that the closing of the door will cause the door to engage against the end 59 of the push button 57 and push the same to its in position illustrated in FIG. 2 when the door is in its closed position. However, the push button 57 is then adapted to move to the out position illustrated in FIG. 1 when the door is moved to an open position thereof.

The operation of the electrical switch construction 10 of this invention as utilized in the electrical control system 11 of this invention will now be described.

When the push button 57 of the electrical switch construction 10 is in the out" position illustrated in FIG. 1, it can be seen that the end 56 of the frusto-conical shaped compression spring 54 is forced into the small diameter cylindrical part 31 of the passage 26 of the housing part 23 by the force of the compression spring 54 so that the first few turns of the spring 54 at the end 56 thereof is disposed in wedging relation with the cylindrical part 31 of the housing part to provide good electrical contact therebetween. Thus, the lead 18 of the electrical control system 11, by being electrically interconnected to the end 55 of the spring 54 at the side 19 of the switch construction 10, is effectively interconnected to ground through the spring 54 and housing part 23 to the grounded lead 21 so that the electrical power source 12 can now operate the control device 16.

For example, the control device 16 can comprise a dome light of an automobile and the electrical power source 12 can comprise the storage battery thereof with the electrical construction 10 being a door-- operated switch of the automobile. Thus, when the car door that operates the particular switch 10 is in the open position to cause the plunger 57 be in the out condition illustrated in FIG. 1, the dome light 16 is now operated by the electrical power source 12 as the electrical circuit is completed through the switch construction 10.

However, when the door is closed to engage against the end 59 of the plunger 57 and move the same inwardly from the position illustrated in FIG. 1 to the position illustrated in FIG. 2, the plunger means 57 has moved the end 56 of the spring 54 completely out of the chamber 31 of the housing part 23 and into the larger diameter chamber 35 whereby the end 56 of the spring 54 is now held out of electrical contact with the housing part 23 so that the electrical circuit between the

sides

19 and 20 of the switch construction 10 is broken and, thus, the control device 16 is no longer operated by the power source 12. Thus, in the case of an automobile door switch, the dome light 16 will be in its off condition if the door for the particular switch construction 10 is in its closed position as illustrated in FIG. 2 and will be in its on condition when the door of the compression spring 54 into the larger diameter cylindrical part 35 of the housing means 23 so as to hold the same in a centered position therein so as to be completely out of electrical contact with the housing part 23 whereby the lead 18 cannot be grounded through the switch construction underthis in condition of the spring 54.

From the above, it can be seen that this invention provides an improved switch construction 10 that can be formed of a relatively few parts and be assembled in a simple and effective manner to provide a switch construction that can operate an electrical control system for opening and closing the circuit means thereof. The sealing means of the switch construction 10 also renders the switch construction 10 of this invention desirable. foroutdoor applications oranywhere that conductive or corrosive liquids may be splashed on the switch construction 10.

Thus, this invention not only provides an improved electrical switch construction, but also this invention provides an electrical control system utilzing such switch construction.

a While the form of the invention now preferred has been disclosed as required by the patent statutes, other forms may be utilized and all come with the scope of the appended claims.

What is claimed is:

1. An, electrical switch construction comprising a housing means having a generally cylindrical internal peripheral surface, a movable plunger means carried by said housing means, and a coiled compression spring means havinga longitudinal axis and being carried by said housing means, said spring means being engageable with said. plunger means, said spring means when in one operative position being in wedged relation radially outwardly of said axis thereof with said internal peripheral surface of said housing means to provide an ing engagement therebetween, said spring means and said housing means and said plunger means being so constructed and arranged that when said plunger means is moved to a certain position relative to said housing means and spring means is moved out of its wedging relation to break said electrical circuit, said electrical circuit through said spring means to said housing means at said wedging engagement therebetween, said spring means and said housing means and said plunger means being so constructed and arranged that when said plunger means is moved to a certain position relative to said housing means said spring means is moved out of its wedging relation to break said electrical circuit by being compressed along its said longitudinal axis. I

2. An electrical switch construction as set forth in claim 1 wherein said housing means has a chamber therein, said spring means being disposed in said chamher.

3. An electrical switch construction as set forth in claim 2 wherein said spring means has opposed ends,

one of said ends being disposed at one end of said chamber and the other end being movable relative to said housing means by said plunger means.

4. An electrical switch construction comprising a housing means, a movable plunger means carried by said housing means, and a compression spring means carried by said housing means and being engageable with said plunger means, said spring means when in one operative position being in wedged relation with said housing means to provide an electrical circuit through said spring meansto said housing means at said wedghousing means having a chamber therein, said spring means being disposed in said chamber, said spring means having opposed ends, one of said ends being disposed at one end of said chamber and the other end being movable relative to said housing means by said plunger means, one of said other end of said spring means and said chamber having a substantially frustoconical portion that provides said wedging relation therebetween when said spring means is in said one operative position thereof.

5. An electrical switch construction as set forth in claim 4 wherein said other end of said spring means has saidfrusto-conical portion, said chamber having a first cylindrical portion and a second cylindrical portion with a larger diameter than said first portion, said other end of said spring means being in said wedging relation when received in said first cylindrical portion and being out of said wedging relation when moved into said second cylindrical portion by said plunger means.

6.;An electrical switch construction as set forth in claim 5 wherein said plunger means has aguide thereon received in said other end of said spring means to guide movement of said other end of said spring means be tween said cylindrical portions of said chamber.

7. An electrical switch construction as set forth in claim 1 wherein said spring means has opposed ends, one of said ends being fixed from movement relative to said housing means and the other end being movable relative to said housing means by said plunger means and providing said wedged and unwedged relation therewith.

8. An electrical switch construction as set forth in claim 7 wherein said housing means has an electrical insulative part carrying said one end of said spring means to electrically isolate said'one end of said spring means from the remainder of said housing means.

. 9. An electrical switch construction comprising a housing means, a movable plunger means carried by said housingmeans, a compression spring means carried by said housing means and being engageable with said plunger means, said spring means when in one operative position being in wedged relation with said housing means to provide an electrical circuit through said spring means to said housing means at said wedging engagement therebetween, said spring means and said housing means and said plunger means being so constructed and arranged that when said plunger means is moved to a certain position relative to said housing means said spring means is moved out of its wedging relation to break said electrical circuit, said spring means having opposed ends, one of said ends being fixed from movement relative to said housing means and the other end being movable relative to said housing means by said plunger means and providing said wedged and unwedged relation therewith, said housing means having an electrical insulative part carrying said one end of said spring means to electrically isolate said one end of said spring means from the remainder of said housing means, and an electrical lead means being electrically connected to said one end of said spring means.

10. An electrical switch construction as set forth in claim 9 wherein said plunger means is formed of electrically non-conductive'material.

11; An electrical control system comprising an electrical power source, an electrical circuit means operatively interconnected to said power source, and an electrical switch construction disposed in said circuit means and having a housing means interconnected to one side of said circuit means and being provided with a generally cylindrical internal peripheral surface, a movable plunger means carried by said housing means, and a coiled compression spring means having a longitudinal axis and being carried by said housing means, said spring means being engageable with said plunger means, said spring means being interconnected to the other sideof said circuit means and .when in one operative position being in wedged relation radially outwardly of said axis thereof with said internal peripheral surface of said housing means to complete said electrical circuit means through said spring means and said housing means at said wedging engagement therebetween, saidspring means and said housing means and said plunger means being so constructed and arranged that when said plunger means is moved to a certain position relative to said housing means said spring means is moved out of its wedging relation to break said electrical circuit means by being compressed along its said longitudinal axis.

12. An electrical control system as set forth in claim 11 wherein said housing means has a chamber therein, said spring means being disposed in said chamber.

13. An electrical control system comprising an electrical power source, an electrical circuit means operatively interconnected to said power source, and an electrical switch construction disposed in said circuit means and having a housing means interconnected to one side of said circuit means, a movable plunger means carried by said housing means, and a compression spring means carried by said housing means and being engageable with said plunger means, said spring means being interconnected to the other side of said circuit means and when in one operative position being in wedged relation with said housing means to complete said electrical circuit means through said spring means and said housing means at said wedging engagement therebetween, said spring means and said housing means and said plunger means being so constructed and arranged that when said plunger means is moved to a certain position relative to said housing means said springmeans is moved out of its wedging relation to break said electrical circuit means, said housing means having a chamber therein, said spring means being disposed in said chamber, said spring means having opposed ends, one of said ends being disposed at one end of said chamber and the other end being movable relative to said housing means by said plunger means.

14. An electrical control system as set forth in claim 13 wherein one of said other end of said spring means and said chamber has a substantially frusto-conical portion that provides said wedging relation therebetween when said spring means is in said one operative position thereof.

15. An electrical control system as set forth in claim 14 wherein said other end of said spring means has said frusto-conical portion, said chamber having a first cylindrical portion and a second cylindrical portion with a larger diameter than said first portion, said other end of said spring means being in said wedging relation when received in said first cylindrical portion and being out of said wedging relation when moved into said second cylindrical portion by said plunger means.

16. An electrical control system as set forth in claim 15 wherein said plunger means has a guide thereon received in said other end of said spring means to guide movement of said other end of said spring means be tween said cylindrical portions of said chamber.

17. An electrical control system comprising an electrical power source, an electrical circuit means operatively interconneced to said power source, and an electrical switch construction disposed in said circuit means and having a housing means interconnected to one side of said circuit means, a movable plunger means carried by said housing means, and a compression spring means carried by said housing means and being engageable with said plunger means, said spring means being interconnected to the other side of said circuit means and when in one operative position being in wedged relation with said housing means to complete said electrical circuit means through said spring means and said housing means at said wedging engagement therebetween, said spring means and said housing means and said plunger means being so constructed and arranged that when said plunger means is moved to a certain position relative to said housing means said spring means is moved out of its wedging relation to break said electrical circuit means, said spring means having opposed ends, one of said ends being fixed from movement relative to said housing means and the other end being movable relative to said housing means by said plunger means and providing said wedged and unwedged relation therewith.

18. An electrical control system as set forth in claim 17 wherein said housing means has an electrical insulative part carrying said one end of said spring means to electrically isolate said one end of said spring means from the remainder of said housing means.

19. An electrical control system as set forth in claim 18 wherein an electrical lead means is electrically connected to said one end of said spring means and comprises said other side of said circuit means.

20. An electrical control system as set forth in claim 19 wherein said plunger means is formed of electrically non-conductive material.

Claims

1. An electrical switch construction comprising a housing means having a generally cylindrical internal peripheral surface, a movable plunger means carried by said housing means, and a coiled compression spring means having a longitudinal axis and being carried by said housing means, said spring means being engageable with said plunger means, said spring means when in one operative position being in wedged relation radially outwardly of said axis thereof with said internal peripheral surface of said housing means to provide an electrical circuit through said spring means to said housing means at said wedging engagement therebetween, said spring means and said housing means and said plunger means being so constructed and arranged that when said plunger means is moved to a certain position relative to said housing means said spring means is moved out of its wedging relation to break said electrical circuit by being compressed along its said longitudinal axis.

2. An electrical switch construction as set forth in claim 1 wherein said housing means has a chamber therein, said spring means being disposed in said chamber.

3. An electrical switch construction as set forth in claim 2 wherein said spring means has opposed ends, one of said ends being disposed at one end of said chamber and the other end being movable relative to said housing means by said plunger means.

4. An electrical switch construction comprising a housing means, a movable plunger means carried by said housing means, and a compression spring means carried by said housing means and being engageable with said plunger means, said spring means when in one operative position being in wedged relation with said housing means to provide an electrical circuit through said spring means to said housing means at said wedging engagement therebetween, said spring means and said housing means and said plunger means being so constructed and arranged that when said plunger means is moved to a certain position relative to said housing means and spring means is moved out of its wedging relation to break said electrical circuit, said housing means having a chamber therein, said spring means being disposed in said chamber, said spring means having opposed ends, one of said ends being disposed at one end of said chamber and the other end being movable relative to said housing means by said plunger means, one of said other end of said spring means and said chamber having a substantially frusto-conical portion that provides said wedging relation therebetween when said spring means is in said one operative position thereof.

5. An electrical switch construction as set forth in claim 4 wherein said other end of said spring means has said frusto-conical portion, said chamber having a first cylindrical portion and a second cylindrical portion with a larger diameter than said first portion, said other end of said spring means being in said wedging relation when received in said first cylindrical portion and being out of said wedging relation when moved into said second cylindrical portion by said plunger means.

6. An electrical switch construction as set forth in claim 5 wherein said plunger means has a guide thereon received in said other end of said spring means to guide movement of said other end of said spring means between said cylindrical portions of said chamber.

8. An electrical switch construction as set forth in claim 7 wherein said housing means has an electrical insulative part carrying said one end of said spring means to electrically isolate said one end of said spring means from the remainder of said housing means.

9. An electrical switch construction comprising a housing means, a movable plunger means carried by said housing means, a compression spring means carried by said housing means and being engageable with said plunger means, said spring means when in one operative position being in wedged relation with said housing means to provide an electrical circuit through said spring means to said housing means at said wedging engagement therebetween, said spring means and said housing means and said plunger means being so constructed and arranged that when said plunger means is moved to a certain position relative to said housing means said spring means is moved out of its wedging relation to break said electrical circuit, said spring means having opposed ends, one of said ends being fixed from movement relative to said housing means and the other end being movable relative to said housing means by said plunger means and providing said wedged and unwedged relation therewith, said housing means having an electrical insulative part carrying said one end of said spring means to electrically isolate said one end of said spring means from the remainder of said housing means, and an electrical lead means being electrically connected to said one end of said spring means.

10. An electrical switch construction as set forth in claim 9 wherein said plunger means is formed of electrically non-conductive material.

11. An electrical control system comprising an electrical power source, an electrical circuit means operatively interconnected to said power source, and an electrical switch construction disposed in said circuit means and having a housing means interconnected to one side of said circuit means and being provided with a generally cylindrical internal peripheral surface, a movable plunger means carried by said housing means, and a coiled compression spring means having a longitudinal axis and being carried by said housing means, said spring means being engageable with said plunger means, said spring means being interconnected to the other side of said circuit means and when in one operative position being in wedged relation radially outwardly of said axis thereof with said internal peripheral surface of said housing means to complete said electrical circuit means through said spring means and said housing means at said wedging engagement therebetween, said spring means and said housing means and said plunger means being so constructed and arranged that when said plunger means is moved to a certain position relative to said housing means said spring means is moved out of its wedging relation to break said electrical circuit means by being compressed along its said longitudinal axis.

13. An electrical control system comprising an electrical power source, an electrical circuit means operatively interconnected to said power source, and an electrical switch construction disposed in said circuit means and having a housing means interconnected to one side of said circuit means, a movable plunger means carried by said housing means, and a compression spring means carried by said housing means and being engageable with said plunger means, said spring means being interconnected to the other side of said circuit means and when in one operative position being in wedged relation with said housing means to complete said electrical circuit means through said spring means and said housing means at said wedGing engagement therebetween, said spring means and said housing means and said plunger means being so constructed and arranged that when said plunger means is moved to a certain position relative to said housing means said spring means is moved out of its wedging relation to break said electrical circuit means, said housing means having a chamber therein, said spring means being disposed in said chamber, said spring means having opposed ends, one of said ends being disposed at one end of said chamber and the other end being movable relative to said housing means by said plunger means.

16. An electrical control system as set forth in claim 15 wherein said plunger means has a guide thereon received in said other end of said spring means to guide movement of said other end of said spring means between said cylindrical portions of said chamber.