US2276428A - Electric switch - Google Patents

Description

Mai'ch 17, 1942. E. M. SORENG ELECTRIC SWITCH Filed May 22; 1959 2 Sheets-Sheet l fe fts l (W 36 LIZ E5595? 507577;

March 17, 1942.

M. SORENG ELECTRIC SWITCH Filed May 22, 1959 j o i 2 Sheets-Sheet 2 Patented Mar. 17, 1942 ELECTRIC SWITCH Edgar M.

Soreng, Chicago,

Ill., assignor to Soreng-Manegold Company, Chicago, 111., a corporation of Illinois Application May 22, 1939, Serial No. 275,100

Claims. (Cl. 200-54) This invention relates to improvements in electric switches, and refers particularly to switches of the type adapted to be operated by the closure of a door, as for instance the door of a refrigerator. Switches of this type generally embody an insulating base which houses the contacts and contactor, and which also carries the necessary terminals by which the switch is connected in an electric circuit.

Heretofore, the design of these switches has been such that the actuator for the contactor moved with a translating motion, This condition led to difiiculties in some installations, and it is therefore an object of this invention to provide a switch of the character described wherein the actuator moves with a swinging pivotal motion to be more readily depressed by the swinging closure of the door.

Another object of this invention is to provide an improved manner of maintaining the constituent parts of the switch assembled.

Another object of this invention is to improve the design of the insulating base to facilitate its manufacture and enable production thereof with a straight line molding operation.

Another object of this invention is to provide a switch of the character described wherein the contactor is shorter than the space between the major portions of the contact members, but longer than the space between their contact portions so that it is impossible to have the switch closed except when the actuator which carries the contactor is in its outwardly projected position.

With the above and other objects in view which will appear as the description proceeds, this invention resides in the novel construction, combination and arrangement of parts substantially as hereinafter described, and more particularly defined by the appended claims, it being understood that such changes in the precise embodiment of the hereindisclosed invention may' be made as come within the scope of the claims.

The accompanying drawings illustrate two complete examples. of the physical embodiment of the invention constructed in accordance with the best modes so far devised for the practical application of the principles thereof, and in which:

Figure l is a top view of a switch constructed in accordance with this invention; Figure 2 is a bottom view thereof;

Figure 3 is a longitudinal sectional view through the switch on the plane of the line 33 in Figure 1;

ders 22.

Figure 4 is a longitudinal sectional view through the switch on the plane of the line 44 in Figure 3;

Figure 5 is a cross sectional view taken through. Figure 3 on the plane of the line 5--5.

Figure 6 is a perspective view of the insulating base and one of the combined contact and terminal members, shown separated;

Figure '7 is a perspective view of the actuator;

Figure 8 is a top view of a slightly modified embodiment of the invention;

Figure 9 is a bottom view thereof;

Figure 10 is a longitudinal sectional view taken through Figure 8 on the plane of the line lO-lfl;

Figure 11 is a longitudinal sectional view taken through Figure 10 on the plane .of the line H-l I; and

Figure 12 is a top plan view of the base of that form of the invention shown in Figures 8 to 11, inclusive, with one of the combined contact and terminal members shown in cross section.

Referring now particularly to the accompanying drawings in which like numerals indicate like parts, the numeral 5 designates a molded insulating base which is of such design as to be capable of production by a straight line molding operation. Any suitable insulating material, such as Bakelite," may be employed.

The-upper end portion 6 of the base is substantially circular in cross section, and its lower portion I is substantially oblong or rectangular in cross section, having arcuate end walls 8 and 9, the latter being longer than the former, and flat side walls IQ of stepped formation, each of which has outer fiat wall surfaces II and I2. With this formation, the upper end portion 6 overhangs the lower portion to provide attaching flanges by which the base is secured to a supporting top plate l3, preferably by rivets H. The supporting plate has attaching ears l5 extending in opposite directions by which the switch is securable to the door frame, or any other suitable support.

A cavity or recess l6 extends down into the base from its upper circular end. This cavity or recess is substantially of oblong shape in transverse cross section and has side walls I! identical in formation, end walls l8 and I9, and a bottom wall 20.

The opposed side walls I! have longitudinally extending grooves 2| near the end wall I 8. These grooves continue from the upper face of the base downwardly to a point near the bottom wall, where they terminate to provide abrupt shoul At their upper ends, the sides of the grooves are cut away to provide notches 23. the bottoms of which serve as shouldersor ledges against which contact portions 24 of combined contact and terminal members 25 are engageable.

The combined contact and terminal members, as best shown in Figure 6, are punched from sheet metal and have a narrow strap-like medial portion 26 at the upper end of which the contact portion 24 is formed by being bent perpendicularly thereto. The contact portion 24, however, is wider than the medial portion 26. At the bottom of the medial portion 26, which is substantially as long as the longitudinal grooves 2| in the side walls of the cavity, there is an abrupt ofiset 21, which joins with a lower terminal portion 28. These terminal portions, like the contact portions, are wider than the medial portion 26.

The offsets 21 engage the shoulders 22 to cooperate with the -engagement of the contact portions 24 with the ledges formed by the notches 23 to restrain the contact and terminal members against downward displacement. Upward displacement thereof is precluded by the top plate H! which overlies the upper end of the contact and terminal members.

The terminal portions 28 are long enough to protrude through openings 29 in the bottom wall of the cavity and have tapped holes for the reception of terminal screws 30. As clearly illustrated in Figure 5, the holes 29 through which the terminal portions protrude have a stepped formation to snugly fit the cross section of the terminal portions, and thus hold the combined contact and terminal members against lateral displacement at their lower ends.

The upper ends of the combined contact and terminal members are restrained against lateral displacement in an edgewise direction by the sides of the grooves 2|, and'in a flatwise direction by having their contact portions 24 engage in longitudinal grooves 3| formed in the end wall l8. Hence, it will be seen that the combined contact and terminal members are firmly held against displacement in any direction upon as-, sembly with the base. and attachment of the top plate i3 thereto.

At the junction of the end wall l9 and the top portion 6 of the base is a notch 32 wider thanthe adjacent portion 33 of the cavity or recess which is reduced in width at this point.-

The ends of this notch 32 provide pockets for the reception of trunnions 34 formed on an actuating member 35. This actuating member 35 is substantially of triangular shape, and is of such design as to enable the same to be produced by a straight line molding operation. It has parallel flat side walls 36 beyond which the trunnions 34 project.

The thickness of the actuator is slightly less than the width of the cavity or recess portion 33 so that the sides of this portion 33 of the cavity and the sides of a longitudinal groove or channel 31 in the opposite end wall i8 engage the sides of the actuator and guide the same for pivotal motion about the axis of its trunnions 34.

The outer edge 38 of the actuator is formed on an arc struck from the center of the trunnions 34 so as to be spaced a uniform distance from the bottomof the groove or channel 31 as it swings into and out of the cavity. The trunnions are held in the pockets-provided by the notch .32 by the top plate l3, which overlies the same and has a rectangular opening 39 just large enough to permit the actuator to pass therethrough.

The portion of the actuator projecting above the top plate i3 thus has one curved edge provided by the arcuate edge 38, and a straight edge 40 which constitutes a cam surface engageable with the door of a refrigerator, or other installation with which the switch is used, during closure of the door to depress the actuator into the cavity against the action of a compression spring 4i.

The compression spring 4| is confined between the bottom wall of the cavity and the lower edge of the actuator, being held against displacement by a tit 42 projecting from the lower edge of the actuator and a lug or tit 43 projecting up from a spring seat 44 formed on the bottom wall 20 of the cavity.

At its outer lower corner, the actuator has an oblong shaped hole 45 passing therethrough. Into this hole a contactor 46 is loosely inserted. The contactor 46 is provided by a metal bar having a slight longitudinal curvature and is so positioned that its outwardly projecting end portions face upwardly to engage the undersurfaces of the contact portions 24 of the combined contact and terminal members when the actuator is in its normal position. to which it is biased by the spring 4|. Being loosely mounted in the hole 45, the contactor is free to adjust itself to the undersurfaces of the contact portions to insure good electrical contact.

It is important to observe that the contactor is substantially shorter than the distance between the medial portions 26 of the combined contact and terminal members so that upon depression of the actuator, it is impossible for the contactor to bridge the contact and terminal members; but, of course, the length of the contactor must be greater than the distance between the contact portions 24.

The modification illustrated in Figures 8 to 12, inclusive, in its essential elements is substantially like that described.

In this construction, the insulating base 50 is cylindrical throughout its entire length, and the top plate 5| is secured thereto by screws 52, or other suitable fastening means.

As in the previously described construction, the base has a cavity of substantially rectangular or oblong shape in cross section. The side walls of this cavity have the combined contact and terminal members 25 mounted therealong, and the actuator 53 is pivotally mounted by means of trunnions 54 seated in notches 55 in the opposite side walls of the recess or cavity.

A coil spring 55 confined between the bottom of the cavity and the bottom of a notch 51 in the actuator yieldingly projects the actuator to its extended outermost position at which a contactor 58 secured thereto by a screw 59 engages the contact portions of the combined contact and terminal members to electrically bridge the adjacent to theupper end of said recess and insulating base having a cavity opening to one end thereof, said cavity having spaced side walls and a bottom wall provided with openings adjacent to the side walls; combined contact and terminal members extending longitudinally along said side walls and having their terminal portions passing through said openings in the bottom wall; contact portions on said combined contact and terminal members near the open end of the cavity and directed inwardly toward the inside of the cavity to be spaced apart a distance less than the spacing between the major portions of the combined contact and terminal members which extend along the side walls of the cavity; an actuator movable in said cavity toward and from the bottom wall thereof with a part disposed between the combined contact and terminal members; a contactor carried by said part of the actuator and extending to opposite sides thereof, said contactor being shorter than the spacing between the major portions of said combined contact and terminal members but longer than the spacing between the contact portions thereof so as to be engageable with the undersurface thereof upon outward motion of the actuator; and means biasing the actuator outwardly to normally maintain the contactor in engagement with said contact portions,

2. In a switch of the character described: an insulating base having a cavity opening to one end, said cavity having spaced side walls provided with longitudinal grooves and having a bottom wall provided with openings therethrough adjacent to the inner ends of said grooves; the side walls at the mouth of the cavity having notches communicating with the adjacent'end of the grooves to provide.ledges; and one of the connecting walls of the cavity between said side walls having an instruck portion overlying the side walls adjacent to said notches; and combined contact and terminal members mounted in said cavity, one along each of said side walls, said combined contact and terminal members having a medial portion disposed in the longitudinal grooves of the side walls and having terminal portions protruding through the holes in the bottom wall of the cavity, and having contact portions bent inwardly at their ends adjacent to the mouth of the cavity, said contact portions being wider than the medial portions and extending into said notches to engage the ledges formed thereby and secure the combined contact and terminal members against longitudinal motion in one direction, and having portions engaging behind the instruck parts of the connecting wall to be held thereby against movement away from the side walls.

3. In a door-operated electric switch, in combination: a one-piece molded insulating, base having an upper end portion of substantially circular form in transverse cross section, the lower port on of said base having diametrically opposite sides offset inwardly with respect to the contour of said upper end portion, whereby the latter provides a pair of diametrically spaced flanges of segmental form; said base having therein a recess of approximately oblong form in transverse cross section opening to the upper end thereof; the bottom wall of said recess having at one end thereof a pair of parallel spaced apart rectangular openings, said bottom wall having at the other end thereof an abutment for a spring; a pair of combined switch contact and terminal members supported within said recess; the contact portions of said members being positioned formed so as to overhang said recess, and the terminal portions extending below said bottom wall thereof through said bottom wall openings; the upper end of said base having a peripheral notch formed therein and communicating with said recess; a molded insulting actuating member of approximately triangular contour positioned within said recess and guided by the side walls of the latter for oscillatory movement in a single plane; one end of said actuating member being pivotally engageable with the bottom wall of said notch, the lower edge portion of said actuating member having an abutment formed thereon intermediate the length thereof; a coiled spring interposed under compression between said abutments and tending to eject said actuating member from said recess; a contactor carried by said actuating member and extending a substantial distance beyond each side thereof to lie between said contact members, said contactor being movable by said actuating member into and out of bridging engagement with said overhanging contact portions; said overhanging contact portions cooperating with said contactor to limit the degree of movement of said actuating member outwardly from said recess; and means comprising an insulating plate secured to the upper end of said base and overlying said overhanging contact portions to restrain the latter against substantial upward displacement; said insulating plate having an opening formed therein to provide oscillatable clearance for said operating member;

4. In an electric switch, in combination: a one-piece molded insulating base having a recess formed therein and opening to the upper surface thereof, said base having a notch formed in the upper surface thereof and communicating with said recess; an insulating actuating member of approximately triangular contour having an end portion positioned within said notch for pivotal movement with respect thereto; an insulating plate secured to the upper end of said base and overlying said notch to restrain said end portion against substantial upward displacement; a pair of spaced contact members posi tioned within said recess at opposite sides of said actuating member, said contact members and the walls of said recess having cooperating shoulders formed thereon to restrain the former against downward displacement; said insulating plate also overlying said contact members to restrain the latter against substantial upward displacement; said actuating member having an elongated slot extending transversely therethrough; a contactor positioned within said slot and having portions projecting beyond opposite sides of said actuating member for movement by the latter into and out of bridging engagement with said contact members; the walls of said recess having vertical grooves formed therein to receive the contact members and restrain the contact members against lateral displacement so that said contact members are held against movement toward each other; said contact members having contact portions at the upper ends thereof directed inwardly from the side walls of the recess to be spaced apart a distance less than the length of the contactor, whereby the contact portions of the contact members coact with the contactor to limit the degree of movement of the actuating member and the contactor outwardly from the recess and said contact members are electrically bridged, and whereby inward movement of the actuator electrically disconnects the contact members even though one end of said contactor may engage one of the contact members.

5. In a door operated electric switch, in com bination: a one piece molded insulating base having a recess formed therein and opening to the upper surface thereof, said base having a notch formed in the upper surface thereof adjacent to one end of the recess and communicating with said recess through a reduced passageway forming a shoulder at its junction with the notch; a molded substantially fiat insulating actuating member of substantially triangular contour; a trunnion formed at one end of said actuating member so as to project from at least one face thereof, said trunnion being positioned within said notch for pivotal movement with respect thereto and engageable with the shoulder to limit movement of the actuating member toward the opposite end of the recess; a spring in said recess arranged to exert a force on the actuating member tending to move the same outwardly of the recess and toward said oppo-' site end thereof; and an insulating member secured to the upper end of said base and overlying said notch to restrain said trunnion against upward displacement and to maintain the same engaged with said shoulder.

6. As an article of manufacture: a combined contact and terminal member adapted for insertion into a cavity of the insulating base of an electric switch, said member comprising a single metal stamping having an elongated narrow medial part joining an abruptly enlarged terminal part at one end, said terminal part continuing in the same direction as the medial part and being punched and tapped at a portion thereof adapted to project to the exterior of the insulating base for the reception of a terminal screw, and said member having a contact por tion at its opposite end, said contact portion being bent substantially perpendicularly to the medial portion and having side arms extending beyond the side edges of the medial portion.

7. As an article of manufacture: a one-piece molded insulating base for electric switches of the door-operated type; said base having an upper end of substantially circular form, and a lower end having side walls offset inwardly with respect to the upper end to provide attaching flanges at the upper end; said base further having a substantially rectangular cavity formed ing element pivotally supported within said recess; a contactor; means connecting the contactor with the actuating element for arcuate movement therewith, said means substantially precluding movement of the contactor relatively to the actuating element in a direction radially to the pivot axis of the actuating element;'the bottom wall of said recess having a pair of substantially rectangular openings therein lying in planes parallel to the opposed side walls of the recess; an abutment formed integrally with said bottom wall adjacent to the other end of the latter; a coiled compression spring interposed between said abutment and said actuating element to normally bias the latter for pivotal movement outwardly of said recess; a pair of combined switch contact and terminal members having portions located within said recess and extending substantially throughout the depth of the latter in parallel relation to each other; said portions and the walls of said recess having cooperating shoulders formed thereon to prevent openings to provide for the passage of contact bers against lateral movement out of said longitudinal grooves.

8. In a door-operated electric switch, in combination: a molded insulating base having a portion of substantially circular form in cross section at one end thereof, said base having a recess of approximately oblong form in transverse cross section extending throughout the major portion of its depth and opening to said end; an actuatdownward displacement of said members; and said members having terminal portions extending through said pair of openings and exposed below the lower surface of said base. I

9. In combination: an insulating cam lever for electric switches of the door-operated type, said lever being of approximately triangular contour and the same being adapted to be produced by a straight line molding operation; said lever having an integral pivot lug formed at one end thereof for bearing engagement with a supporting base of suitable form; the lower edge of said lever having an integral projection formed thereon intermediate the ends thereof for engagement by the end of a coiled compression spring; said lever having a slot extending transversely therethrough; a bridging contactor of a size to substantially fit said slot so as to be held thereby against motion relative to the lever except in a direction transversely of the lever whereby the contactor is freely insertable through said slot; the end portions of said contactor extending substantial distances beyond opposite sides of said lever; said lever having an upwardly angled straight edge adapted for engagement by a door or the like to effect pivotal movement of said lever about the center defined by said lug; and said lever having an outwardly curved edge extending between the outer ends of said straight and lower edges.

10. In a door-operated electric switch, in combination: a one piece molded insulating base having a recess formed therein and opening to the upper surface thereof, said base having a notch formed in the upper surface thereof and communicating with said recess; a molded insulating actuating member of substantially triangular contour having an end portion formed to provide a pivot lug, said lug being positioned within said notch for pivotal movement with respect thereto; an insulating member secured to the upper end of said base and overlying said notch to restrain said lug against substantial upward displacement; a pair of punched sheet metal contact members positioned within said recess at opposite sides of said actuating member, said contact members having cooperative engagement with said base to restrain the former against downward and lateral displacement; said insulating member overlying said-contact members to restrain the latter against substantial upward displacement; a contactor; a driving connection between the contactor and said actuating memtom wall of said recess and with the lower edge of said actuating member between said pivot lug and said contactor to thereby bias said actuating member outwardly from said recess; said contactor cooperating with said contact members and said actuating member to limit the degree of outward pivotal movement of the latter; and

said contact members having conductive portions formed integrally therewith to provide for 0 attachment of terminal wires.

EDGAR M. SORENG.

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