US3032623A - Snap-action switch - Google Patents

Description

1, 1962 c. A. BALL, JR 3,032,623

SNAP-ACTION SWITCH Filed Oct. 19, 1959 k 15 12 Fax. 2 19 57 42 1121 35 6 A?) 1Q j 13 &5 34 12 2 35.

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United rates 3,032,623 Patented May 1, 1962 3,932,623 SNAP-ACTIQN SWITCH Charles A. Ball, Jr., Highland Park, Ill., assignor to Cherry Electrical Products Corp., Highland Paris, 111., a corporation of Illinois Filed Oct. 19, 1959, Ser. No. 847,265 1 Claim. (Cl. 200-67) My invention relates to a new and useful improvement in a snap-action switch and more particularly to an electrical switch having a contact movable between contact bearing terminals.

An object of my invention is in the provision in a switch of this character of a movable switch blade that is caused to be moved with a snap-action between contact bearing terminals.

Another object of my invention is in the provision in a switch of this character of an arrangement of parts whereby the contact pressure between the movable contact and a fixed contact is increased prior to the snapactiou movement of a movable switch blade.

A further object of my invention is in the provision in a switch of this character of a flexible contact blade which in its normal assembledposition is caused to assume a natural wave throughout its longitudinal length, which wave is responsible for the contact pressure between contacts and a snap-action movement of the blade when the natural wave thereof is deformed.

Other objects will appear hereinafter.

The invention consists in the novel combination and arrangement of parts to be hereinafter described and claimed.

The invention will be best understood by reference to the accompanying drawings showing the preferred form of construction and in which:

FIG. 1 is an elevational view of my improved snapaction switch;

FIG. 2 is a top plan view of the same; FIG. 3 is a side elevational View of my switch showing the cover removed;

FIG. 4 is a side elevational view similar to FIG. 3 but showing the parts thereof in actuated position; and

FIG. 5 is a perspective view of my flexing contact blade in its natural unmounted condition.

Referring to FIG. 1 I show a housing for my improved switch. This housing 10 comprises complementary sections 11 and 12 with the sections being mounted together in facial relationship by means of rivets 13. Adapted to project out of the ends 14 and 15 of each of the sections 11 and 12 is a pair of spaced apart fixed contact bearing terminals 16 and 17. Adapted to project out of the opposite ends 18 and 19 of the sections 11 and 12 is one end 20 of a flexing contact blade 21.

As each of the sections 11 and 12 are identical, I will describe but one. Referring to FIGS. 3 and 4 I show therein a side elevational view of section 11. This section 11 is provided with cavities 22 and 23. These cavities 22 and 23 are separated by opposing triangularly shaped projections 24 and 25 formed as an integral part of the section 11. The apex of each of these triangular sections 24 and 25 are sufliciently spaced apart to permit the positioning therebetween of a portion of the flexing contact blade 21. In the end wall 26 of the cavity 22 there is provided a V-notch 27 extending transversely to the longitudinal length of the section 11. Formed in the end wall 28 of the cavity 23 is a like V-notch 29 which also extends transversely to the longitudinal length of the section 11.

It should be noted that the flexing contact blade 21 is of a length greater than the distance between the V- notches 27 and 29 hereinbefore described. Therefore, when the flexing contact blade 21 is positioned within the housing 10 with its one end 30 seated in the V-notch 27, and the shoulders 31 and 32 formed in its opposite end, positioned in the V-notch 29, the blade 21 will be forced to assume a natural wave such as is shown in FIG. 3. This natural wave in the blade 21 is so formed that opposite peaks thereof are disposed on opposite sides of the triangularly shaped projections 24 and 25 in each of the cavities 22 and 23. In order to maintain the flexing contact blade 21 in its natural waved condition I provide a conical coiled return spring 33. This spring 33 sits in a recess 34 formed in the base of the cavity 23. The purpose and function of the return spring 33 will be hereinafter made apparent.

Formed in the section 11 is a passage 35 which has open communication with a recess 36 formed in the top wall of the cavity 23. An actuator 37 is positioned within the passage 35 and is adapted to be reciprocated therethrough. This actuator 37 terminates inwardly of the section 11 into an enlarged head portion 38 which is adapt ed to sit in the recess 36 formed in the top wall of the cavity 23. This enlarged head 38 is provided with a nipple 39 which is adapted to engage the flexing contact blade 21 on the side opposite the engagement of the spring 33 with such blade 21 which is at the highest point of elevation of the wave formed in the blade 21 as seen in. FIG. 3.

In actuating my improved snap-action switch the actuator 37 is depressed so that the enlarged head 38 thereof will force the wave 40 of the flexing contact blade 21 between the V-notch 29 and the projections 24 and 25 to be depressed downwardly against the action of the spring 33. When the wave 40 has its highest point thereof indented and depressed below the centerline that extends between the V- notches 27 and 29 the flexing contact blade 21 will cause a reversing of the peaks of the wave such as is shown in FIG. 4. By the flexing of the restricted natural wave of the blade 21 into a reverse wave, a snap-action movement takes place through that portion 42 of the blade 21 which lies in the cavity 22 between the V-notch 27 and the apex of the triangular portions 24 and 25. By such snap-action the contact 43 carried by that portion 42 of the blade 21 is moved into engagement with the contact 44 and the terminal 16 and out of engagement with the contact 45 of the terminal 17. When the moving force is removed from the actuator 37 the reverse waving of the blade 21 is accomplished by the return spring 33.

It should be noted that the blade 21 in its normal position has suflicient end forces applied to that portion 42 by reason of its disposition between the V-notch 27 and the restriction of the triangular sections 24 and 25 that there is produced a desired contact pressure between the contact 43 and the contact 45. When the actuator 37 is depressed and the wave 40 is forced to assume a deformed condition the contact pressure between the contacts 43 and 45 is increased until the snap-action movement takes place as hereinocfore described.

While I have illustrated and described the preferred form of construction for carrying my invention into effect, this is capable of variation and modification without departing from the spirit of the invention. I, therefore, do not wish to be limited to the precise details of construction set forth, but desire to avail myself of such variations and modifications as come within the scope of the appended claim.

Having thus described my invention, what I claim as new and desire to protect by Letters Patent is:

A tease-proof snap-action switch comprising a housing having a pair of adjacent cavities, internal projections separating said cavities and each having upper and lower sections formed substantially triangularly in cross-section with their apexes in abutting relation with respect to each other, a pair of terminal plates carried by said housing at one end thereof and having portions extending into the adjacent cavity and opposite end portions extending externa'lly of the housing, contact heads carried by said terminal plates in opposed relation with respect to each other in said adjacent cavity, said housing providing in opposite end walls within said cavities aligned V-shaped seats, a switch blade arranged within the housing and extending between said apexes and said terminal plates, one end of said switch blade reduced to provide oppositely disposed shoulders and an elongated terminal adapted to extend exteriorly of the housing in a direction opposite to said terminal plates, said switch blade between said shoulders and the other end thereof being of a length greater than the distance between said seats whereby when said switch blade is arranged in said housing with said shoulders and said other end thereof in engagement with said seats said blade will be undulated longitudinally to provide alternate bowed portions one within each of the cavities, said other end of said switch blade having contacts thereon for alternate engagement with the contacts of said terminal plates, and means for alternately bowing said switch blade to cause the contacts carried thereby to have said alternate engagement with the contacts of said terminal plates, said means including a movable actuator carried by the housing and engaging the switch blade at one side thereof, and

a coil spring arranged in said housing in alignment withv said actuator and engaging the opposite side of said blade to resist movement of said actuator to flex said switch blade in an opposite direction.

References Cited in the file of this patent

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