US 3325618 A
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Description (OCR text may contain errors)
June 13, 1967 .1. F. SULLIVAN ELECTRIC LINE SWITCH WITH IMPROVED TRIGGER HINGE 2 Sheets-Sheet 1 Filed June 23, 1965 INVENTOR. Jams: F1 \SULLJ'VqA/ Q WW f lacs :4 7' TOEA/ r5 June 13, 1967 J. F. SULLIVAN ELECTRIC LINE SWITCH WITH IMPROVED TRIGGER HINGE 2 SheetsSheet 2 Filed June 23, 1965 NTOR. J4me: F. JULLIl/AAK INVE , jmg m s? rroeA/s. Y5
United States Patent G AETRAT DEECLQFQURE A hinge member is mounted on one side or a switch base and is provided with flat integral trunnions projecting from its opposite edges. A trigger with a longitudinal channel in it facing the base has resilient tongues ic-rmed in its side walls and provided with openings for pivotally receiving the trunnions of the hinge member when the tongues are sprung apart to permit them to slide over the trunnions.
An example of such a switch is shown in the copending patent application of Dudley H. Campbell and James F. Sullivan, Ser. No. 392,180, filed Aug. 26, 1964 now Patent No. 3,250,882. In that trigger switch, one end of the spring contact is provided with a loop that contains the hinge pin on which the trigger is pivotally moun ed. The hinge, therefore, forms part of the electric circuit when the switch is closed.
It is among the objects of this invention to provide an electric switch of the general type just referred to, which has a simpler and less expensive hinge or pivot, which does not require a separate hinge pin, which does not always require the current to flow through the hinge, and which permits the trigger and hin e to be quickly assembled.
In accordance with this invention, a fixed contact is mounted on one side of an insulating base. Mounted on the same side of the base is a hinge member that is spaced from the contact. The hinge member is provided with a pair of trunnions proiecting from its oppoiste edges and spaced from the base. The hinge member projects into a longitudinal channel formed in a trigger that extends across the contact. The sides of the trigger are provided with openings pivotally receiving the trunnions to permit the trigger to be swung toward and away from the fixed contact. A spring contact is formed from a metal strip having a mounting portion that is connected to the base adjacent to the hinge trunnions, with the strip extending away from the mounting portion and across the fixed contact, from which it normally is spaced. The trigger is movable toward the base far enough to force the free end of the spring contact into engagement with the fixed contact. The hinge member may be fastened to the spring contact or even made integral with it.
The invention is illustrated in the accompanying drawings, in which FIG. 1 is a side view of one form of switch, with parts broken away;
FIG. 2 is a plan view thereof;
PEG. 3 is a cross-section taken on the line III-III of FIG. 1;
FIG. 4 is a side view, with the trigger shown in longitudinal section, of a modification;
FIG. 5 is a view, similar to FIG. 4, of another embodiment of the invention;
FIG. 6 is a side view of a still further embodiment;
FIG. 7 is an enlarged cross-section taken on the line VHVII of FIG. 6; and
Patented June 13, 1967 FIG. 8 is a perspective view of a modified spring contact.
Referring to FIGS. 1, 2 and 3 of the drawings, an insulating base member 1 may have any desired shape, although usually it will be relatively long and narrow. A fixed electric contact 2 is mounted on one side of the base near one end. A terminal 3 extends through the base and connects to the contact. The two may be integral and held in place by a rivet 4. The contact may be mounted rigidly on the base or one end of it may be spaced a short distance from the base to give the contact some spring.
For engaging the fixed contact, there is a spring contact s that is formed from a resilient metal strip extending lengthwise of the base 1. This strip has a mounting portion 7 spaced laterally from the fixed contact and located near the opposite end of the base. The mounting portion is secured to the base by any suitable means, such as by a rivet 8. The major part of the strip extends from the rivet toward and across the fixed contact, but normally is spaced from it. The free end of the strip, spaced outwardly from the fixed contact, is connected to the mounting portion by an outwardly extending hump portion 9 having sides converging away from the base.
It is the feature of this invention that at the opposite end of the mountin portion the spring strip is bent outwardly away form the base, as shown in FIG. 1, and then parallel to the base and back toward it to extend through the base and form the second terminal 11 of the switch. This terminal also helps keep the switch from turning on the rivet. The outwardly bent or ofiset portion of the strip between rivet 8 and its terminal forms a hinge member 12, the opposite edges of which have lateral projections forming trunnions 13 that are spaced a short distance from the base.
For closing the switch, there is an actuating trigger 15 formed of any suitable material, such as a plastic. The trigger is provided with a longitudinal channel 316 facing the base 8 and having closed ends. This channel receives the hump of the spring contact and the hinge member 12. The channel is long enough to extend across the fixed contact. To pivotally connect the trigger to the base, the opposite sides of the trigger beside the hinge member are provided with openings 17 that receive the hinge trunnions. The openings are shaped to permit the opposite end of the trigger to be swung toward and away from the base. The trunnions may have any desired cross-sectional shape and the openings in the trigger will be shaped accordingly.
The trigger can be applied to hinge member 12 in at least two difjerent ways. One way is to form the trigger initially with bendable sides far enough apart to receive the hinge trunnions, and then press the sides inwardly to cause the trunnions to project into the trigger openings. A preferred Way of assembling these elements is to provide the trigger with enough spring in its side walls to permit them to be sprung apart by the trunnions when the trigger is pressed down over them until the trunnions are aligned with the trigger openings, whereup the trigger sides will snap inwardly and hold the trunnions. For this purpose, the inner edges of the side walls adjacent to the trunnions should be beveled as shown in FIG. 3 to help spring the walls apart as they are forced down over the trunnions. If the trigger walls, themselves, are too stiff to be sprung apart for this purpose, the portions of the walls beside the hinge member can be made more resilient by providing them with slots 19 extending outwardly away from the base on opposite sides of openings 17 in order to form spring tongues 2t move far enough to force the free end of the spring contact into engagament with the fixed contact to close the switch. The free end of the trigger may be provided with a projecting lip 21 designed to serve as astop against a portion of the housing (not shown) in which the switch is mounted, whereby to limit outward swinging of the trigger.
In the modification shown in FIG. 4, the switch is a single pole, double throw, switch with two fixed contacts 25 and 26 mounted on an insulating base 27 and provided with terminals 28 and 29, respectively. The two contacts overlap, with the free end of a'spring contact 31 between them. Although the spring contact could be made the same as the one just described, a variation is shown in which the outer end of the contact strip is secured in any suitable manner to a separate hinge member 32. This member is L-shape, with its lower portion fastened to base 27 and a terminal 33 by means of a rivet 34. Of course, the contact and terminal could be integral, if desired. Projecting from the opposite edges of the upright portion of the hinge member are trunnions 36 that are snapped into openings 37 in the side walls of a trigger 38 to pivotally connect the trigger to the base. The hollow trigger fits over the hinge member and contacts and has an inside boss 39 engaging the spring contact, which normally engages the upper fixed contact 25. If desired, a coil spring 40 may be compressed between the base and the spring contact to help hold the latter in its upper position. When the free end of the trigger is pressed down, the boss will push the spring contact down into engagement with the other fixed contact 26. Current flows through the hinge member while the trigger is in either of its extreme positions.
The switch shown in FIG. 5 likewise has an insulating base 42 and a trigger 43. The trigger is pivotally connected at one end to the base by means of a hinge member 44 like the one shown in FIG. 4. The hinge member is provided with laterally projecting trunnions 45 extending into openings 46 in the sides of the trigger. The hinge member is fastened to the base by a rivet 47, but unlike the first two switches there is no terminal connected with the hinge member. Instead, the spring contact 49 is separate from the hinge member and insulated from it. That is, one end of the spring contact is secured to the base by a rivet 50. An extension of the spring strip extends through the base to form a terminal 51. The opposite end of the spring contact overlies a fixed contact 52 riveted to the base and extending through it to form the other terminal 53. When the free end of the trigger is pressed toward the base, a boss 54 inside the trigger presses the spring contact against the fixed contact to close the switch. It will be seen that no current passes through the hinge member.
In FIGS. 6 and 7, there is illustrated a single pole, double throw switch that normally is open. In this switch there is a fixed contact 55 mounted on an insulating base 56 near each end of the base. Each contact has a terminal 57. A long spring strip 58 has a central mounting portion 59 engaging the central portion of the base, and free ends extending across both fixed contacts. The ends of the spring contact are connected to its central mounting portion by hump portions 6%). Near its center, the mounting portion of the spring contact is attached to the base by a suitable fastener, such as -a rivet 61. A terminal also is joined to the mounting portion. If desired, it can be formed by a tongue 63 struck out of the spring strip and projecting through the base. At the opposite edges of the center of the mounting portion of the strip, there CJI is a pair of projecting ears that are bent upwardly and then outwardly to form a hinge member with trunnions 64 spaced from the base. These trunnions project into pivot openings 65 in the opposite sides of a channel shape trigger 66 that also is in the shape of a flattened letter V so that the two end portions of the trigger are inclined from its center outwardly away from the base. When either end of the trigger is pressed toward the base, the trigger wiil pivot or rock on the trunnions and press one end of the spring contact against the adjoining fixed coritact. When the trigger is released, it Will be rocked back to switch-open position by means of the spring contact.
Another way of forming the hinge member is shown in FIG. 8, where it will be seen that the central portion of the mounting portion of the spring contact 70 has been bent outwardly to form a hinge member 71 provided with trunnions 72 for a rocking trigger. A terminal (not shown) can be joined to the contact in any suitable manner.
According to the provisions of the patent statutes, I have explained the principle of my invention and have illustrated and described what I now consider to represent its best embodiment. However, I desire to have it understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically illustrated and described.
1. An electric switch comprising an insulating base, a fixed contact mounted on one side of the base, a hinge member spaced from said contact and mounted on said side of the base, said member being provided with flat integral trunnions projecting from its opposite edges and spaced from the base, a trigger-provided with a longitudinal channel facing the base and receiving said hinge nember and extending therefrom across said contact, the sides of the trigger being provided with openings pivotally receiving said trunnions to permit the trigger to be swung toward and away from the fixed contact, said trigger sides being provided with slots extending outwardly away from said base on opposite sides of said openings to provide resilient tongues capable of being sprung apart for insertion of said trunnions in the openings, a spring contact at said side of the base formed from a resilient metal strip having a mounting portion, and means connecting said mounting portion to the base adjacent said trunnions with the strip extending away from said means and across the fixed contact normally out of engagement therewith, said trigger being movable toward the base far enough to force the free end of the spring contact into engagement with the fixed contact 2. An electric switch comprising an insulating base, a fixed contact mounted on one side of the base and having a terminal, a spring contact formed from a resilient metal strip having a mounting portion near one end spaced laterally from the fixed contact, means securing said mounting portion to said side of the base with the major part of the strip extending from one end of the mounting portion toward and across the fixed contact normally out of engagement therewith, the strip at the opposite end of the mounting portion being provided with a portion bent outwardly away from the base, the end of the strip adjoining said bent portion extending inwardly toward the base and through it to form a second terminal, the opposite free end of the strip being connected to said mounting portion by an outwardly extending hump portion having converging sides, said bent portion of the strip 7 being provided with a pair of fiat integral projections forming trunnions projecting from its opposite edges spaced from the base, and a trigger provided with a longitudinal channel facing the base and receiving said bent and hump portions, the channel extending across the fixed contact, the sides of the trigger at one end being provided with openings pivotally receiving said trunnions to permit the opposite end of the trigger to be swung toward 6 and away from the fixed contact, said trigger sides being References Cited provided with slots extending outwardly away from said UNITED STATES PATENTS base on opposite sides of said openings to provide resilient 1 925 422 9/1933 W I h 200 172 t 1 f a s ongues cap b e of bemg sprung apart or lnser 101'! of 531 3,072,761 1/1963 Ponsy 200 159 X trunnions in the openings, said hump portion engaging 5 the inner transverse wall of said channel and normally 3,200,213 8/1965 Murphyspacing said opposite end of the trigger from the base, 3,250,882 5/ 1960 Campbell et 200159 and the trigger being movable toward the base far enough to force said free end of the spring contact into engage- ROBERT SCHAEFER Prmary Exammerment with the fixed contact. 10 H. BURKS, Assistant Examiner.