US3519776A

US3519776A - Electrical switch of the toggle type with the toggle also serving as the movable contact and supported by a conductive groove

Info

Publication number: US3519776A
Application number: US694696A
Authority: US
Inventors: Thomas S Slater
Original assignee: Slater Electric Inc
Current assignee: Slater Electric Inc
Priority date: 1967-12-29
Filing date: 1967-12-29
Publication date: 1970-07-07
Anticipated expiration: 1987-07-07
Also published as: FR1602231A

Description

July 7 1970 I T. s. SLATER 3,519,776 ELECTRICAL SWITCH OF THE TOGGLE TYPE WITH THE TOGGLE ALSO A. SERVING AS THE MOVABLE CONTACT AND SUPPORTED I3 A CONDUCTIVE GROOVE I 1 Filed Dec. 29, 1967 FIG.. 1A F'G 2 ATTORNEYS United States Patent M U.S. Cl. 200-154 13 Claims ABSTRACT OF THE DISCLOSURE There is described herein an electrical switch of the toggle type which is, however, intended for use in alternating current circuits in which switches of the leaf spring type are commonly used. The switch consists essentially of an operating handle, a toggle member which is also the moving Contact member, and a fixed contact, all being mounted in a usual type of electrically insulating housing, the device being provided with the usual mounting strap which serves also to hold the operating handle in position in the housing. The toggle member is formed of resilient cylindrical wire and has two non-colinear straight portions. A bearing in the form of an electrically conductive groove extends parallel to the direction of one of said toggle straight portions, and is in supporting contact with said straight portion over a longitudinal distance large compared with the diameter of said wire. The other one of said toggle straight portions is engaged by said operating handle and oscillating movable therewith.

Electrical alternating current switches in common use consist of a leaf spring carrying a movable contact, at least one fixed contact mounted on a resilient arm, an operating handle having a camming surface for flexing the leaf spring to move the movable contact toward and away from the contact member, a coil spring to move the operating handle to its alternate position and stops to limit the handle movement, the stops being provided with rubber bumpers to cushion the movement and eliminate noise. The handle spring is necessary to assure that the handle will have a positive action since otherwise the switch would need to be made to high tolerances.

The switch of this invention does not require high tolerances, utilizes a spring which is also the current carrying element, thus eliminating both the handle spring and the concomitant bumpers and at the same time provides proper contact pressures. Also, the handle member has no camming surfaces which must be molded or otherwise formed to exactcontour, but instead utilizes a simple slot or aperture. A switch is thus provided which, in addition to the advantages set forth above, may be made extremely small and still retain the desired operating characteristics, and which in addition does not require stops to limit the motion of the operating handle since the toggle spring itself takes care of this.

It is therefore an object of the invention to provide an electrical toggle switch which is simple in construction, readily and inexpensively manufactured, and which at the same time has good operating characteristics and is extremely compact.

Other features of the invention will be apparent when the following description is considered in connection with the annexed drawings in which:

FIG. 1 is a vertical cross-sectional view of the switch of my invention, the view being taken on the plane of the line 11 of FIG. 2;

FIG. 2 is a vertical cross-sectional view taken on a 3,519,776 Patented July 7, 1970 lCC plane transverse to the plane of FIG. l and adjacent one side wall of the switch, the operating handle and toggle member being shown in a central instantaneous position;

FIG. 3 is a view similar to FIG. 1, but showing the construction of a second form of my invention in which the toggle member is in tension rather than in compression. This View is taken on the plane of the line 3-3 of FIG. 4; and

FIG. 4 is a vertical cross-sectional View taken on a plane transverse to that of FIG. 3` and adjacent one of the side walls of the switch, showing the toggle member and operating handle in a vertical instantaneous position.

Referring now to the drawings, and particularly to FIGS. l and 2 thereof, it will be seen that the switch elements are supported within a housing 10, which ordinarily is moulded of insulating material. The housing 10 is provided with pairs of

internal ribs

12 and 13 which form guideways for

terminals

14 and 15 respectively, into which connecting

screws

16 and 17 are threaded as shown particularly in FIG. l. It will be noted that if the switch is to be a simple single-pole, single-throw switch, one of the

terminals

14 or 15 may be omitted.

A generally similar terminal 18- is mounted in guideways formed in ribs 20 integral with the side wall of the housing 10, the ribs 20 being spaced and notched near their upper ends to form a seat which supports the lefthand one of a pair of

trunnions

21 and 22 formed on the operating handle 23. The second trunnion 22 is supported in a seat 24 formed in the opposite side wall of housing 10, the operating handle being held in position by the usual mounting strap 25 which is fixed to the housing in any suitable manner, as for example, by ears bent olf from the strap and indicated at 26, which may enter depressions in, or lie beneath projections formed on, the outer wall of the housing.

The contact and toggle member of this switch consists of a loop of resilient wire 30 of good electrical conducting properties, which wire loop is mounted for pivotal movement about an axis extending transversely of the switch body and in the plane of the axis of the operating handle 23. As shown in the drawings, the pivotal seat for the wire loop 30 is a generally V-shaped extension 31 of the terminal 18, which seat extends from the side wall at the left of FIG. 2 toward the opposite side wall. As shown in the drawing, there is also a bent terminal portion of the loop or U-shaped toggle and contact member 30 which extends downwardly through a slot. in the V-shaped seat 31, thus assuring that the loop 30 twill not slide in its seat 31 while being free to oscillate therein.

The operating handle 23 is provided with the usual inner extension 28 which in this instance is bifurcated at its end, as indicated at 27, the bifurcation straddling the upper portion of the loop 30. Since the loop 30 is in this instance formed so that it tends to expand and the ends thereof separate to a predetermined degree, it will be seen that as the operating handle 23 and of course the projection 28 reach the vertical position, the loop is compressed and that as it moves slightly beyond this central position, the expansion of the loop, resulting from its inherent resiliency, causes the operating handle and the loop to pivot about their respective axes so that the end of the loop moves toward one of the two fixed contacts which are mounted as indicated particularly in FIG. l, at the e'nds of upwardly extending

arms

34 and 35 integral with the

terminals

14 and 15, the contacts proper being designated 36 and 37. Since in its relaxed condition the ends of loop 30 are separated a predetermined amount, separate stops, although preferable, are not required and only those stops used as contacts and required by the circuit usage need be supplied.

As shown in FIGS. 1 and 2, a contact piece 38 is lixed to the upper end of the loop 30 to cooperate with

contacts

36 and 37. If desirable, however, this contact piece 38 can be omitted, since the wire loop will itself make contact with the fixed contacts. The use of the contact piece 38 is merely to assure that the material of the contact will be proper and the area of contact will be increased and thus to assure that the tendency of the switch to arc or weld when used is decreased.

Referring now to FIGS. 3 and 4, the switch shown in these drawings is a modification of that shown in FIGS. 1 and 2 and is so similar that in general the same reference characters have been utilized. lIn large part, the description heretofore given with respect to FIGS. l and 2 is applicable and need not be repeated.

As is clear from FIGS. 3 and 4, the extension 31 of the terminal member has been reversed so that the seat 31 now faces with the apex of the V upwardly rather than downwardly as before. The handle 23, instead of having the bifurcated end 27, is provided with an aperture 40 extending therethrough and in addition, the

contacts

36 and 37 are mounted on

arms

34 and 35, which are somewhat differently shaped than in the switch of FIG. l. Also, in this instance the contact 38 has been replaced by two

pieces

41 and 42 suitably fixed to opposite sides of the wire loop 30.

The switch of FIGS. 3 and 4 operates in substantially the same manner as that of FIGS. 1 and 2, the difference being quite obvious and consisting of the fact that the pivotal mounting of the upper arm of the loop 30 lies above the pivotal mounting of the handle 23, and the loop 30 is formed so that its ends tend to move toward each other.

The operation of the switch is however, identical. As the Switch passes over-center, the loop is spread and as the operating handle passes beyond the center part, the loop, due to its inherent resiliency, tends to contract and thus causes the operating handle and the loop itself to move to a limiting position such as shown in FIG. 3, in which a circuit is completed through the terminal 18, seat 31, loop 30, contact 42, to the terminal 15.

While I have described preferred embodiments of my invention, it will be apparent that many variations may be devised without departing from the spirit thereof. For example, the wire loop 30 instead of being U shaped may be in the form of an S or a Z or even a simple acute or obtuse angle with one leg pivotally mounted and the other engaged by the operating handle; the contact making portion of the toggle may instead of being part of or xed to the non-pivotally mounted portion be fixed to the pivotally mounted portion and extend at an angle therefrom to provide a greater separation of contacts mounted in its path; the handle may be of the rocker type rather than a simple handle, the contact moved by the toggle member may be insulated from that member and connected to its terminal by a flexible lead, etc.

Thus, it will be obvious that many variations and modifications may be made. I wish therefore to be limited not by the foregoing description, but solely by the claims granted to me.

What is claimed is:

1. An electrical switch of the dual position type comprising, in combination, a resilient contact member including a unitary cylindrical wire having a straight first porton and a second portion not colinear with said first portion, a bearing in the form of an electrically conductive strip having a groove generally conforming in crosssectional dimension Iwith said first portion of said contact member, said rgroove extending parallel to the direction of said first portion of said contact member, said ibearing being formed at least in part of an electrically conductive material and in supporting contact with said first portion of said contact member over a longitudinal distance large compared with the diameter of said wire so that said contact member is supported for rotation 4 about said first portion as an axis, a movably mounted operating member, engaging means on said operating member engaging with said contact member to produce oscillation of the second portion of said contact member in response to motion of said operating member, said engaging means causing said contact member to be resiliently distorted in a central portion of its range of oscillation, and at least one fixed contact located in the path of a conductive portion of said contact member conductively connected to the second portion of said contact member.

2. An electrical switch as claimed in claim 1 wherein said wire has at least one bend therein and the end portions of said wire are parallel to each other.

3. An electrical switch as claimed in claim 1 wherein said bearing and said fixed contact are provided respectively with means for connecting said elements into an external circuit.

4. An electrical switch as claimed in claim 1 wherein two fixed contacts are provided, one adjacent each limit of travel of said contact member.

5. An electrical switch as claimed in claim 1 wherein said contact member has at least one contact mounted thereon, said contact being positioned to engage said fixed contact adjacent one extreme of movement of said contact member.

6. An electrical switch of the dual position type comprising, in combination, a housing, a resilient contact member including a unitary cylindrical wire having a straight first portion and a second portion not colinear with said first portion, a bearing in the form of an electrically conductive strip having a groove generally conforming in crosssectional dimension with said first portion of said contact member, said groove extending parallel to the direction of said first portion of said contact member, said bearing being formed at least in part of an electrically conductive material and in supporting -contact with said first portion of said contact member over a longitudinal distance large compared with the diameter of said wire so that said contact member is supported for rotation about said iirst portion as an axis, a handle, means pivotally mounting said handle for oscillation about an axis parallel to said contact member rotation axis, engaging means on said handle engaging the second portion of said contact member to cause said contact member to move from one rest position to another and during such movement to sequentially deform and return to its initial state Ias said operating handle is oscillated, and at least one fixed contact located inthe path of a conductive portion of said contact member conductively connected to the second portion of said contact member and adjacent one of said rest positions of said contact member.

7. An electrical switch as claimed in claim 6 wherein said contact member is in the form of an electrically conductive `wire bent in the form of a U, one arm of said U being mounted in said bearing, and wherein said engaging means engages the other arm of said U, said U being stressed during movement of said handle from an initial position to the center point of its travel, said U thereafter restoring and driving said handle to its other limit of movement, said other arm of said U engaging a fixed contact adjacent at least one of the rest positions of said handle and contact member.

`8. An electrical switch as claimed in claim 6 wherein said fixed contact is spaced from said engaging means and said contact member is formed of resilient material between said fixed contact and said engaging means whereby said contact member resiliently absorbs the impact generated as said contact member strikes said fixed contact.

9. An electrical switch as claimed in claim 7 wherein said handle means engaging said other larm of said U shaped toggle member is positioned on the same side of said pivotal mounting as said U shaped toggle member, said other arm of said U being bent toward said one arm as the handle is moved from an initial rest position to a center position, said U expanding after passage thereof through said center point, said contact forming a stop for said contact member oscillation in one rest position, move ment of said handle and contact member in the correspondingly opposite directions being limited by the return of said U to its relaxed state.

10. An electrical switch as claimed in claim 6 wherein a fixed contact is provided adjacent the limit of travel of said contact member in each direction.

11. An electrical switch as claimed in claim 9 wherein said engaging means comprises a bifurcated projection on said handle, said other arm of said U extending through said bifurcation.

12. An electrical switch of the toggle type comprising, in combination, a housing, a shaped resilient contact and toggle member comprising electrically conductive material, said toggle member having two portions at an angle to each other, a seat formed at least in part of electrically conductive material mounting said toggle member for oscillation about one of said portions as an axis, a handle, means pivotally mounting said handle for oscillation about an axis in a common plane with and parallel to said toggle portion axis, means on said handle engaging the other portion of said toggle member to cause said member to move from one rest position to another and during such movement to sequentially deform and return to its initial state as said operating handle is oscillated, and at least one contact in the path of oscillation of said other portion ad-I jacent one of said rest positions, said contact member being in the form of an electrically conductive strip bent in the form of a U, one arm of said U being mounted in said seat, and wherein said engaging means engages the other arm of said U, said U being stressed during movement of said handle from an initial position to the center point of its travel, said U thereafter restoring and driving said handle to its other limit of movement, said other arm of said U engaging a ixed contact adjacent at least one of the rest positions of said handle and toggle member, said handle means engaging said other arm of said U being located on the opposite side of said handle pivotal mounting from said U shaped toggle member, said other arm of said U being bent away from said one arm as the handle is moved from its initial rest position to a center position, said U contracting after passage through the center point of its travel to force said handle and said U to continue movement in the same direction, said movement being limited by contraction of said U to its normal relaxed state, said motion in at least one direction being limited by said at least one fixed contact.

13. An electrical switch of the toggle type comprising, in combination, a housing, a shaped resilient contact and toggle member comprising electrically conductive material, said toggle member having two portions at an angle to each other, a seat formed at least in part of electrically conductive material mounting said toggle member for oscillation about one of said portions as an axis, a handle,

means pivotally mounting said handle for oscillation about an axis in a common plane with and parallel to said toggle portion axis, means on said handle engaging the other portion of said toggle member to cause said member to move from one rest position to another and during such movement to sequentially deform and return to its initial state as said operating handle is oscillated, and at least one contact in the path of oscillation of said other portion adjacent one of said rest positions, said contact member being in the form of an electrically conductive strip bent in the form of a U, one arm of said U being mounted in said seat, and 4wherein said engaging means engages the other arm of said U, said U being stressed during movement of said handle from an initial position to the center point of its travel, said U thereafter restoring and driving said handle to its other limit of movement, said other arm of said U engaging a fixed contact adjacent at least one of the rest positions of said handle and toggle member, said handle means engaging said other arm of said U Ibeing located on the opposite side of said handle pivotal mounting from said U shaped toggle member, said other arm of said U being bent away from said one arm as the handle is moved from its initial rest position to a center position, said U contracting after passage through the center point of its travel to force Said handle and said U to continue movement in the same direction, said movement being limited by contraction of said U to its normal relaxed state, said motion in at least one direction being limited by said at least one iixed contact, said engaging means comprising a hole in said handle, said other arm of said U extending through said hole.

References Cited UNITED STATES PATENTS 2,457,153 12/1948 Hubbell. 2,737,557 3/1956' Johnson 200--154 3,213,227 10/ 1965 Heath. 3,359,392 12/1967l Heath.

FOREIGN PATENTS 1,219,900 5 1960 France.

493,989 5/ 1954 Italy. 1,150,552 1/1958 France.

OTHER REFERENCES Addition #76,950 to reference #1,233,560, French Patent Disclosure, Societe, Nov. 6, 1951.

ROBERT K. SCHAEFER, Primary Examiner R. A. VANDERHYE, Assistant Examiner U.S. Cl. X.R. 20G-67, 166, 172