US2788409A - Snap switch - Google Patents

Description

April 9, 1957 P. D. GRovER SNAP SWITCH F'iled Dec. 9, 1955 SNAP SWITCH Philip D. Grover, Chicago, ill., assignor to Grover Products Corporation, a corporation of Illinois Application December 9, 1955, Serial No. 552,216 1 Claim. (Cl. 200-67) This invention relates to an electrical switch and, more particularly, to an electrical switch of the snap action type.

This invention is an improvement over the snap switch disclosed in a copending application of Philip D. Grover, Serial No. 529,719, tiled August 22, 1955.

The general object of this invention is to provide a new and improved snap switch.

Another object of this invention is to provide a new and improved snap switch which is extremely compact and sensitive, and in which the parts are easy to assemble and economical to produce.

A further object of this invention is to provide a new and improved snap switch in which the actuating member is constructed of wire and is hingedly mounted directly on and between a pair of switch-actuating members.

A still further object of this invention is to provide new and improved compression springs to function between both dat toggle arm members, and wire toggle arm members, or any combination thereof, to provide snap action in a switch, thus avoiding arcs and prolonging contact and hence switch life.

Other objects and advantages will become apparent fromthe following detailed description taken in connection with the accompanying drawings, in which:

Fig. 1 is a front elevational View of an embodiment of the invention;

Fig. 2 is a top plan view of the embodiment of Fig. l;

Fig. 3 is a perspective view of the resilient blade members of the embodiment shown in Fig. 1;

Fig. 3a is a front elevational view of the wire spring actuating member of Fig. 1;

Fig. 3b is a front elevational View of a modified form of wire spring actuating member adapted to be used with the flat resilient blade members shown in Fig. 3;

Fig. 3c is a front elevational view of a further modi fication of such a wire spring actuating member;

Fig. 3d is a front elevational view of still another modification of such a wire spring actuating member;

Fig. 4 is a perspective view of a modified form of i'lat resilient blade members;

Fig. 4a is an enlarged perspective view of a wire spring actuating member adapted to be used with the blade members of Fig. 4;

Fig. 5 is a perspective View of another embodiment of the invention; and Fig. 5a is an enlarged perspective view of a modified form of wire spring actuating member adapted to be used with the embodiment shownin Fig. 5.

While the invention s herein described withreference to a number of preferred embodiments, it is not intended to limit the invention to the specific forms and arrangements shown, it being contemplated that various changes may be made by those skilled in the art without departing from the spirit and scope of the appended claims.

Referring now to Figs. 1, 2, 3 and 3a for a detailed aired States Patent description of one embodiment of the invention, there is shown a base member 6 made of a dielectric material and having a raised or blade supporting portion 7 at one end and a vertically extending bore 8 formed intermediate the ends thereof.

As illustrated in the embdoiment shown, the switch is of a single pole double throw type and has lower and upper xed contacts and intermediate movable ycontacts carried on a switch blade. A lower contact 10 is secured on the base member 6 and an upper contact 11 is supported vertically above the lower contact 10 on a post 12 made of a dielectric material. The -contact 10 has a terminal portion 13 and the Contact 11 has a terminal portion 14. Means for selectively completing a circuit through the contact lll or 11 include a flat resilient switch blade member l5 having one end secured to the raised portion 7 of the base member 6 and a free end disposed `between the contacts 10 and 11. ln the embodiment shown, the switch blade member 15 is secured Ito the raised portion r7 of the base member 6 by a bolt 16 and has a terminal portion 1'7. Secured at the tree end of the blade member 15 are an upper contact 18 and a lower contact 19. The lower movable contact 19 is normally in engagement with the lower fixed contact 10, as shown in Fig. l.

A second ilat resilient blade member 20 having one end secured to the base 6 and a free end spaced from the free end of the switch blade member l5 is provided. Although the blade members 15 and 2() may be separate members and independently mounted, in the embodiment of the invention shown the second blade member 20 is an integral portion of the switch blade member 15 and extends into an elongated opening 21 formed in the switch blade member 15, the blade member 2t) being relatively shorter than the switch blade member 15 so as to define a space between the free ends of the two blade members 15 and 20. As best shown in Fig. 2, the blade member 20 has a slot 22 formed therein with an enlarged circular end portion 23 of a size to allow an actuating pin 24 to be passed therethrough, The pin 24 has an annular groove 25 formed therein adapted to tit in the slot 22, thus allowing the pin 24 to be connectable to the blade member 20, the pin 24 being slidably mounted in the bore 8 in the base 6. Thus, a push or pull movement of the pin 24 is operable to bend the free end of the blade member 20 out of its usual plane.

In the embodiment shown in Figs. l, 2 and 3, a first V-shaped notch 26 is formed in the free end of the switch blade member 15 opening towards the second blade member 20. A second V-shaped notch 2:7 is formed in the free end of the second blade member 20 in alignment with the iirst notch 26.

To provide the desired snap action in moving the switch blade member 15 from the lower fixed contact 10 to the upper fixed contact 11, a compressible wire spring actuating member 28 is mounted between the free ends of the resilient blade members 15 and 20. The wire spring member' 2S includes a central compressible bent portion 29 and end portions 30 and 3l. The end portions 30 and 31 are formed with outwardly opening U- or V- shaped portions 32 and 33 which. are especially well adapted for a hinge type mounting in the notches 26 and 27, respectively. As shown in Fig. 2, the wire spring member 28 is disposed substantially in a vertical plane between the free ends of the blade members 15 and 26.

The wire spring members are mounted in the notches while under some compression, this compression acting to maintain the J-shaped end portions against rounded ends of the notches. The V-shape of the notches 26 and 27 improves the stability of the wire spring member 2S by preventing movement thereof along the ends of the resilient blade members. The end portions of the wire spring member 28 may be ol U- or V-shape and could also be mounted in small holes formed in the ends of the resilient blade members, but the use of notches simplies assembly and provides a preferred hinge action between the `ends of the wire spring member and the resilient blade members.

Additional wire spring members which could be substituted for the wire spring member 2d in the embodiment shown in Figs. 1, 2 and 3 are shown in Figs. 3b, 3c and 3d. These three modications of wire spring members Vary only in the central compressible 'portion and include one, 34, disclosing multiple bends in a. vertical plane, another, 35, disclosing a generally helical coil and another, 36, disclosing a single loop in a vertical plane. Although only four wire spring members have been Shown in the drawings, numerous other modifications would be equally well adapted for use with the switch shown in Figs. l and 2.

As to the operation of this snap switch, when the pin 24 is pushed or pulled downwardly, the second blade member Ztl is bent downwardly, thus compressing the central portion 29 of the wire spring member 2S. When the free end of the second blade member 2d reaches a predetermined position, the compressed wire spring memn ber 28 is operable to shift the switch blade member l5 upwardly with a snap action to close the normally open upper contacts 11 and 18 and to open the normally closed lower contacts l@ and i9. Movement of the pin 24 in the yopposite direction snaps the switch blade member l5 downwardly to again close the normally closed lower contacts l and T9 and to open the normally open upper contacts lll and 18.

Further modilications of the resilient blade members and the wire spring actuating members are shown in Figs. 4, 4a, 5 and 5a. Fig. 4 shows a switch blade member 37 and an integral second blade member 3S. The free end of the switch blade member 37 has a pair of spaced notches 39 and 44B formed therein while the free `end of the second blade member 3S has a relatively wide slot 4l formed therein. A wire spring actuating member 42 shown in Fig. 4a is adapted to be mounted between the blade members 37 and 3d and is formed with two parallel compressible bow portions 43 and 44, a connecting `v'shaped end portion 4S adapted to be hingedly mounted in the slot il and spaced V-shaped end portions 46 and i7 adapted to be hingedly mounted in the notches 39 and 40, respectively.

The embodiment shown in Fig. shows a snap switch wherein one of the toggle members is a resilient blade member and the other toggle member is a relatively stiff formed wire member, the compressible wire actuating member being mounted therebetween. The embodiment includes a base Stl having a raised or switch supported portion 5l at one end with a laterally extending groove 52 formed therein. A switch blade member 53 has one end mounted on the raise-l portion Slt and a free end adapted to engage contacts. A relatively stitl formed wire toggle member has a laterally extending end portion S4 pivotally mounted in the groove 52, a short blade member 55 extending over the top of the groove 52 to hold the end portion 5d in the groove 52, a longitudinally extending portion 56, a laterally extending portion 57, a longitudinally extending portion 53, and a laterally extending end portion 59 adapted to act as a bearing pin.

4 A wire spring actuating member 60 has a central compressible portion 61, a laterally extending helical end portion 62 mounted on the bearing pin end portion 59 of the wire toggle member and a V-shaped end portion 63 hingedly mounted in a V-shaped notch 64 formed in the switch blade member 53. A push or pull movement on the laterally extending portion 57 of the wire toggle member is operable to cause the snap-action movement of the switch blade member 53. This portion 57 extending laterally of the switch provides an excellent bearing for the attachment of a suitable motivator for push or pull movement of the wire toggle member. A modified form of wire spring actuating member 65 adapted to be used with the embodiment of Fig. 5 is shown in Fig. 5a and includes a central single loop portion 66, a laterally extending helical end portion 67 adapted to iit over the bearing pin end portion 59 of the wire toggle member and a J-shaped end portion 63 adapted to be positioned in the V-shaped notch 64 formed in the switch blade member 53.

It should be noted that further modiiications are possible within the language of the appended claims, and that the described modifications are not intended to be limiting. For instance, in accordance with the present invention, a switch could be provided wherein the shorter blade member carries the contacts and is snapped back and forth as a result of a push or pull force applied to the longer blade member. t is believed evident that the actuating toggle member may either be biased so as to provide a .self-returning action to its initial position or non-biased, depending upon the use for which the switch is intended.

I claim:

A snap switch comprising, a base member, a switch blade of resilient material secured at one end to the base and carrying a pair of contacts on opposite sides of its other end, said switch blade having a cut-out portion therein defining an opening and a second blade integral with the switch blade adjacent said one end thereof and having a free portion extending toward the other end ot the switch blade at an angle to the plane thereof, a first notch formed in the switch blade adjacent said other end thereof with the notch opening into said cut-out portion, a second notch formed in the free end of the second blade, cooperating contacts supported in spaced relation to said other end of the switch blade for engagement with the contacts thereon, and means for pivotally moving the second blade relative to the switch blade to cause the engagement of either contact on the switch blade with one or the other of said cooperating contacts with a snap action including a wire compression spring disposed in said opening, said spring having tl-shaped end portions each engaging a diierent notch and a compressible bent portion therebetween, said notches and the direction of stress of the spring lying substantially in a single line normal to the axis of pivotal movement of the second blade, and means engageable with the second blade for pivotally moving the second blade.

References Cited in the tile of this patent.

UNITED STATES PATENTS 1,334,784 Newton Mar. 23, 1920 2,521,015 McLaren et al Sept. 5, 1950 2,568,652 Miller et al. Sept. 18, i951 2,748,215 Davis May 29, 1956 FOREIGN PATENTS 648,682 Great Britain Ian. l0, 1952

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