US2790866A

US2790866A - Snap-action switches

Info

Publication number: US2790866A
Application number: US485709A
Authority: US
Inventors: Jr Walter L Cherry
Original assignee: Cherry Electrical Products Corp
Current assignee: Cherry Corp
Priority date: 1955-02-02
Filing date: 1955-02-02
Publication date: 1957-04-30
Anticipated expiration: 1974-04-30

Description

April 30, 1957 w. L. CHERRY, JR 2,790,866

SNAP-ACTION SWITCHES Filed Feb. 2; 1955 2 Sheets-Sheet 1 "NON-CON.

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I N V EN TOR. 141 44 25k b. 6km dz April 30, 1957 w. L. CHERRY, JR 2,790,866

SNAP-ACTION SWITCHES Filed Feb. 2, 1955 2 Sheets-Sheet 2 SNAP-ACTION SWITCHES Walter L. Cherry, Jr., Highland Park, 11L, assignor to Cherry Electrical Products Corporation, l-lighiand Park, Ill., a corporation of Illinois Application February 2, 1955, Serial No. 485,709

3 Claims. (Cl. 200-67) the same is in motion, the moving contact blade moves at a predetermined rateof speedin one direction independently of any further movement of the actuator, thereby providing what is known in-the art as a tease proof switch.

Yet another and equally important object of. the invention is to provide a snap' action switch simple in construction, economical in manufacture, and-highly ellicient' in use;

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 a plan view' of the invention;

Fig. 2 is a typical side elevational View of the same;

Fig. 3 is a sectional detail'view taken. substantially on line 3'3 of Fig. 2;

Fig. 4 is an end elevational view of the invention as viewed in the direction of' line l -4 of Fig". 2';

Fig.- 5 is a perspective view of the actuator embodied in the invention;

Fig. 6 is a perspective view of a contact-bearing post embodied in the invention;

Fig. 7 is a perspective view of the switch bl'a'd'e embodied in the invention;

Fig. 8 is a perspective view of a mounting bracket embodied in the invention;

Fig. 9 is a perspective view of an actuating link cmbodied in the invention;

Fig. 10 is a plan view of a modifiedform of the invention;

Fig. ll is a typical side elevational view of the same;

Fig. 12 is an end elevational view thereof as viewed in the direction of line 1212 of Fig. ll;

Fig. 13 is a sectional detail view taken substantially on line 13-13 of Fig; 11;

Fig. 14 is a perspective view or" the actuator embodied in the invention shown in Fig. 10, with one end of the tension spring connected thereto and the opposite end of such spring connected to a link;

Fig. 15 is a perspective view of a non-conductive plate embodied in the invention shown in 10;

States Patent O Fig. 16 is a perspective view of the switch blade embodied in the invention. shown in :Fig. 10;

Fig. 17 is a perspective view of the bracket which provides a seat for the Switchblade shown in Fig. 16.

Preferably I accomplish the several objects of my invention by the form of construction shown in the accompanying drawings. In this connection, 10 indicates a mounting plate formed of any suitable non-conductive material. On this mounting plate Ill-at one end thereof is secured as at 11 one end of an actuator 12. This actuator 12 is formed of spring material and bent to provide a flange 13 which is securedto the plate 10 as at 11. Extending upwardly from the flange 13 is an upright portion 14, fromwhich extends the free end portion 15 of the actuator. The upright portion 14 supports the free end portion of the actuator in a plane substantially parallel with and in spaced relation with respect to the plate 10. The end 17 of, the actuator is bent downwardly and then outwardly as at- 18.

The switch blade is indicated at 19 and is likewise formed of such material as will best serve the purpose. One end portion 20 of the blade 19 provides spaced: parallel fingersZl which project into notches or slots 22 formed inthe upright portion 14. of the actuator 12 adjacent theflange 13.

The opposite end portion 22"of theblade 19 provides parallelly extending fingers 23'. which. engage inti-shaped notches 24 formedvin-asubst-antially U.-shaped actuating link 25.

Secured to. the bight- 2'6-ofithis link 25 is one. end portion 27 of. a springdfi theopposite end portion of the spring. being connected to the. extension. 18. of the actuator 12' at a point below the plane. of the portion. 15 thereof.

On the plate 10 is secured. a. stop 29f havingv at. its outer end' portion, an angularly'bent extension 35? even lying the spring. 23 and arranged to. engage the exten: sion 18', whereby to limit upward. movement of the actuator 12. as seen in Fig. 2. Thisstopl isprrovided with a cut-out portion fi lwithin which. operates the bight: portion 26 of the. link 25 andservihgto'l-imi'tthepivotal. action of thelink- 25 in: an anti-clockwise: direction,. as viewed in. Fig. 2, under the. action of the. actuator-i2.- The stop 29 also serves to limit return movement; of the actuator 12. a

The switch blade 19 provides arectangularly shaped. opening 32; Positioned in this opening 32 beneath. the free endportion 15 of the actuator andconnected to the. plate itl'as at 33 in any suitable mannetgis an. arm 34, one end 35 of. which overliesthe switchblade 19. and carries a contact.head'36. This.headisadapted'to have bearing engagement with a companion:contacthead 37 carried by the blade. Thearm: 34 provides a terminal 38; as does the flange 13 of the actuator. Tothese terminals38 and 38" are connected the ends of a conductor wire (not shown).

The switch blade 19; when in the position shown in Fig; 2, bears against a non-conductive stud 39;.thereby limiting its pivotal movement in adownward direction as viewed in Fig. 2'; Substituted, for, this stud.39 may be a contact head similar, to the'head 36,..tor. engagement, with the switch blade 19, thereby to convert the switch into a double-throw switch, i-fdesired.

The switch blade 19 and" the actuatorlink 25 form together a toggle normally under compression and in which the link 25' under the action of thespring z causes the" blade to flex downwardly insnap-action contact with the stud 39; The spring. ZEN-under tension bearsthe link against the stop30.

When pressure is applied" to the free, end portion. 15. of the actuator, 12; it will'be flexed against its own. re,- sistance. The flexin of' such actuator will cause the spring 28 to exert an overthrow pull on the link 25, pivoting the same about its point of pivotal connection with the blade 19. As the link approaches a straight line position with respect to the blade,19, such blade will be compressed against the upright 14 at the point of pivotal connection therewith, so that as soon as the link crosses such straight line, the blade will flex in snap action, bringing the contact head 37 into engagement with the contact head 36. Such contacts will remain in engagement until the pressure is relieved from the actuator, at which time the actuator 12 will return to its starting or initial position, causing the spring 28 to exert an overthrow pull on the link 25 in an opposite direction to flex the blade 19 in an opposite direction in snap-like action to disengage the contact heads 36 and 37. The stud 39 serves to limit the movement of the blade in this latter direction.

The contact pressure between the contact heads 36 and 37 increases as the actuator 12 approaches the terminus of its movement from starting position. Such an arrangement prevents overheating of the contact heads due to lack of intimate mating and also eliminates chatter due to vibration or the like.

In Figs. 10 to 17 inclusive I have shown a modified form of construction for accomplishing the several objects of my invention. In this connection, the mounting plate is of non-conductive material and is indicated at 39. The mounting plate 39 is provided with suitable openings 40 for mounting screws, bolts or the like. At one end portion of the mounting plate is mounted a rigid bracket 41 having a terminal 42 to which an electric wire (not shown) may be attached. The bracket 41 has a horizontal portion 43 which extends in parallel spaced relation with the plate 39. This portion 43 carries a contact head 44 in spaced relation with respect to a contact head 45 carried by the plate 39 and connected in a suitable manner to a terminal 46 to which a conductor wire (not shown) may be attached.

At the opposite end portion of the plate 39 is a rigid bracket'47 having a vertically extending portion 48 extending at substantitally a right "angle with respect to the plate 39. This bracket 47 also provides a terminal 49 to which an electric wire may be attached. The bracket 47 as illustrated in Fig. 17 in its portion 48 provides spaced notches 50 into which fingers 51 of a switch blade 52 project. The bracket provides a V-shaped seat 53 into which the edge 54 of the blade 52 is seated. The blade 52 in the modified form of construction is formed of spring material and is substantially elongated in plan view and is provided with an opening 55 into which project lateral fingers 56. On opposite sides of the blade 52 are carried contact heads 57 for alternate engagement with the contact heads 44 and 45.

A substantially U-shaped rigid link 58 has in its arm portions 59 V-shaped notches 60 into which the fingers 56 engage to provide a pivotal connection between the link 58 and the blade 52. To the bight portion 61 of the link is connected in any suitable manner, one end portion of a tension spring 62, the opposite end portion 62' of the spring being connected to an extension 63 formed on a depending arm 64 of an actuator 65 formed of spring material, or such material as will best serve the purpose. This actuator has a reversely bent end portion 66 to provide a flange connected to the plate 39 at the point of connection between the plate 39 and the bracket 47.

To complete the invention, I provide a suitable plate of nonconductive material carried by the horizontally extending portion 43 of the bracket 41 and extending in the path of movement of thelink 58 to provide a stop therefor limiting the pivotal movement of the link in an anticlockwise direction as viewed in Fig. 11.

The operation of the switch in its modified form of construction, as shown in Figs. 10 to 17, is substantially the same as the operation'of the switch shown in Figs.

4 1 to 9 inclusive, both switches accomplishing substantially the same objects and results.

In the modified form, the pressure of the actuator exerted to flex the switch blade is at a point intermediate the end portions of the blade, whereas in the form shown in Figs. 1 to 9 inclusive, such pressure is at the free end portion of the blade. As in the case of the form of the switch shown in Figs. 1 to 9, as the actuator 65 of the modified form of construction approaches its terminus of movement, the pressure between the engaging contact heads is increased, thus assuring proper contact and eliminating arcing, overheating, and the like.

It will be apparent that I provide a snap-action switch capable of accomplishing the several objects of the invention by a construction which comprises the minimum number of parts, with the result that the same can be manufiactu-red at an economical cost, resulting in a switch which will be highly eflicient in use.

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 dcparting from the spirit of the invention. 1, 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 claims.

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

1. A snap-action switch comprising a non-conductive mounting plate, a flexible elongated actuator having one end portion bent to provide a flange secured to the plate for supporting an opposite free end portion of the actuator in parallel spaced relation with respect to the plate, an arm secured to the plate beneath the free end portion of the actuator and having an end portion extending in parallel spaced relation with respect to the plate, an elongated switch blade arranged between the plate and the free end portion of the actuator and extending in parallel relation with respect thereto, said actuator at its bent end portion and said switch blade at one end there of, having cooperative means for supporting said switch blade in parallel relation with respect to the free end portion of the actuator and the plate, a substantially U-shaped link in length-wise relation with respect to the opposite end portion of the switch blade and having one end portion in pivotal abutment with respect to said opposite end portion of the switch blade, a stop carried by the plate and overlying the end portion of the link opposite the end portion thereof in abutment with the switch blade to limit pivotal movement of the link in one direction with respect to the blade, a spring member having one end portion connected to the end of the free end portion of the actuator and an opposite end portion connected to the end portion of the link beneath said stop, a contact member carried by the plate beneath the end portion of the arm extending in parallel relation to the plate, and a contact member carried by the switch blade intermediate its end portions and in confronting relation with respect to the contact member carried by the plate.

2. A snap-action switch comprising a mounting plate, an actuator having one end portion secured to the plate and having an elongated flexible free end portion extending in parallel spaced relation with respect to said plate, an elongated switch blade extending in parallel relation with respect to and between the free end portion of the actuator and the plate, a contact member adjacent one end portion of the blade, means providing pivotal connection between the actuator and the opposite end of the blade at a point between the plate and the free end portion of the actuator, a link having one end portion in end abutment with and extending from said one end portion of the blade, means providing pivotal connection between the link and the blade at their point of abutment with respect to each other, said actuator having at its free end portion a right angular extension extending toward said plate and disposed to bisect the long axis of the blade when the actuator is flexed in one direction, a spring member connected to said extension and to the link at a point opposite the latters abutment with respect to the blade to pivot the blade in a direction opposite to the pivotal movement of the link when the latter is pivoted by flexing of the actuator in said one direction, stop means carried by the plate and cooperating with the extension of said actuator to limit the pivotal movement of said link in one direction relative to the blade by action of said spring member, and a fixed contact carried by said plate in position to be engaged by the contact of said blade.

3. The device defined by claim 2 in which the means providing the pivotal connection between the actuator and the blade comprises opposite slots formed in the actuator adjacent the end portion thereof secured to the plate and opposite fingers provided by the blade and engaging in said slots.

References Cited in the file of this patent UNITED STATES PATENTS 1,743,073 Simmons Jan. 7, 1930 1,762,075 Petersen June 3, 1930 2,157,156 Abendroth May 9, 1939 2,313,341 Holmes Mar. 9, 1943 2,405,014 Caparone July 30, 1946 2,446,307 Shaw Aug. 3, 1948 2,487,374 Ri-che et a1. Nov. 8, 1949 2,515,528 Rothwell July 18, 1950 2,601,152 Kmiecik June 17, 1952 2,631,205 Millard Mar. 10, 1953 2,651,690 Raney Sept. 8, 1953 2,728,826 Lauder Dec. 27, 1955