US2778904A

US2778904A - Switch terminal head having insulative terminal separators

Info

Publication number: US2778904A
Application number: US489441A
Authority: US
Inventors: Edward N Jacobi
Original assignee: Briggs and Stratton Corp
Current assignee: Briggs and Stratton Corp
Priority date: 1955-02-21
Filing date: 1955-02-21
Publication date: 1957-01-22
Anticipated expiration: 1974-01-22

Description

Jan. 22, 1957 E. N. JACOB! 2,7?8364 SWITCH TERMINAL HEAD HAVING INSULATIVE TERMINAL SEPARATORS Filed Feb. 2]., 1955 Edward AIL/2750i! gww United States Patent SWITCH TERMINAL HEAD HAVING INSULATIVE TERMINAL SEPARATORS EdwardN. Jacobi, Milwaukee, Wis., assignor to Briggs & Stratton Corporation, Milwaukee, Wis., a corporation of-Delaware Application February 21, 1955, Serial No. 489,441

2 Claims. (Cl. 200-168) This invention relates to electric switches and refers more particularly to a terminal head especially suitable for a switch having a rotatable contactor, such as the automobile ignition-start switch disclosed in the copendingapplication of Edward N. Jacobi, Serial No. 474,4l7, filed December 10, 1954.

In general it is an object of this invention to provide an inexpensive terminal head for a switch having a rotatable contactor, which terminal head may be readily stamped out of insulative sheet material and quickly and cheaply assembled into a switch.

Another object of this invention is to provide a terminal head comprising an insulative disk having terminals to which conductors may be secured projecting from onev face thereof and with insulative partition members between the. terminals to isolate the terminals from one another and prevent inadvertent contact between conductors secured to them.

Still. another object of this invention is to provide insulative partition members for thus isolating the terminals of arotatable switch, which partition members may be. fabricated as cheap and simple stampings and are held in place. on a switch by cooperation with the terminal head and with those portions of the switch housing by which the terminal head is held in place on the housing.

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 thats'uch changes in the precise embodiment of the hereindisclosed'invention may be madeas'come within the-scope ot'th'eclaiins.

The accompanying drawing illustrates one complete example of the physical embodiment of the invention constructed according to the best mode so far devised for the practical application of the principles thereof, and in which:

Figure l is a fragmentary side elevational view of a switch having the terminal head of this invention installed thereon, portions being broken away;

Figure 2 is a disassembled perspective view of the terminal head of this invention;

Figure 3 is an end elevational view of the switch shown in Figure l, a portion of the switch housing being broken away; and

Figure 4 is a fragmentary sectional view taken on the plane of the line 4-4 in Figure 3.

Referring now more particularly to the accompanying drawing, the numeral 5 designates generally a switch, such as an automobile ignition-start switch, only the rear portion of which is shown and which comprises a housing having a substantially tubular or cylindrical wall 6. The rear wall of the switch housing i provided by a terminal head designated generally by 7 and comprising a disk 8 of insulative material having a number of fixed contacts 9 exposed at its front face and terminals 10 projecting from its rear surface, with insulative partition 2,778,904 Patented Jan. 22, 1957 members 11 interposed between the terminals to insure against inadvertent contact betwen' conductors secured to the terminals.

The disk may be readily stamped or punched from any suitable insulative plate or sheet material, such as plastic impregnated paper laminate. It is secured in place across the rear of the switch housing by confinement of its edge portion between a forwardly facing circumferential shoulder 12, provided by rolling in the rear edge portion of the cylindrical housing wall, and a rearwardly facing circumferential shoulder 13 on the inner surface of the cylindrical housing wall which may be formed integrally with the housing, as by the junction of a rearwardly opening counterbore 14in which the disk is seated with the bore 15 in the housing. A small spline lug 16 in the housing engages in a mating notch 17 in the periphery of the disk to insure correct orientation of the disk, and hence of the terminals thereon, with respect to the remainder of the switch mechanism.

Each of the terminals 10 projecting behind the disk comprises the rear portion of a stud having an enlarged head exposed at the front of the disk to provide one of the fixed contacts 9, the rear terminal portion of the stud being preferably threaded to facilitate connection of a conductor thereto by means of a nut (not shown).

The several studs should be radially spaced from the center of the disk and circumferentially spaced from one another, but may be disposed on the terminal head in any desired manner to cooperate with whatever rotatable contactor (not shown) is employed in the switch mechanism. The locations of the contacts and terminals on the terminal head are determined by the locations of holes 18 in the disk, in which the studs have a press fit. The contact arrangement shown in the drawing corresponds to that of the contacts on the switch of the aforesaid copending application, the herein disclosed terminal head being adapted for use with that switch, and the lug 9a on one of the stationary contacts of the present terminal head is intended to cooperate with the rotatable contactor in a manner described in said application.

The two partition members 11, whereby each of the terminals is isolated from its neighbors to prevent'inadvertent contact between the conductors connected with the several terminals, are stamped from insulative material which may be similar to that fromwhich the disk is fabricated but is preferably of lesser thickness. In general the shape of the partition members is not important and they may be semicircular, rectangular or substantially trapezoidal, as shown, but each should have a substantially straight longitudinal edge 21 which abuts the fiat rear surface of the housing when the partition members are installed on the switch with their surfaces substantially normal to the rear face of the disk. One partition member has a medial slot 22 opening to the longitudinal edge 21 thereof, and the other partition member has a medial slot 23 opening to its opposite longitudinal edge, the depth of the slot in each case being half the width of the partition member, and these slots permit the partition members to be assembled with the medial portion of each partition member received in the slot in the other to hold the members together in cruciform relation, with their surfaces substantially perpendicular to one another and their longitudinal edges 21 coplanar.

The partition members, connected in this crosswise relationship, are secured to the disk, each extending substantially diametrically across the rear face thereof and with its surfaces perpendicular thereto, by means of a pair of integral tongues 24 on each partition member. The tongues comprise endwise extensions of the partition member and project laterally beyond the longitudinal edge 21 to be snugly received in endwise aligned,

elongated slots 25 in the disk, opening to the periphery thereof. The width of the tongue is substantially equal to the thickness of the sheet or plate material from which the disk is stamped, and the length of the partition members is such that the outer edges of the tongues are even with the edge of the disk, hence the tongues are con- ,fined between the circumferential shoulders 12 and 13 on the cylindrical'housing wall and the partition memv bers are thereby held in place across the rear face of the disk.

While the partition members preferably extend substantially diametrically'across the disk, they may be disposed a little to one side of the center of the disk, as shown. In any event the elongated slots 25 are substantially radial and equispaced circumferentially around the disk, and are arranged in opposite pairswith the two terminal head may be cheaply and inexpensively fabricated from a few simple parts stamped out of insulative sheet or plate material and has insulative partitions between its terminals to preclude inadvertent contact between conductors attached to the terminals.

What I claim as my invention is:

' 1. In a switch of the type having a housing with a tubular wall portion; means on said housing wall portion, near one end thereof, providing a pair of radially inwardly projecting axially opposed circumferential shoulders; a flat disk of insulative material having its peripheral portion tightly confined between said shoulders and thereby secured across said end of the housing, said disk having a pair of opposite substantially radially elongated slots opening to its periphery; a pair of studs secured in said disk at opposite sides of a line joining said slots and spaced from the center of the disk, each of said studs having a head exposed at the inner face of the disk to provide a stationary switch contact in the housing and an elongated body portion projecting through the disk and beyond said end of the housing to provide I to the outer face of the disk, said tongues having portions in said slots projecting substantially radially outwardly to the periphery of the disk and tightly confined between said shoulders on the housing wall, whereby the partition member is fixed to the housing in a position interposed between said terminals to preclude inadvertent contact between conductors secured to said terminals.

2. In an electrical instrumentality of the character described: a tubular housing; means on one end of the housing providing a pair of inwardly projecting axially spaced and opposing circumferential shoulders; at flat insulative disk extending across said end of the housing and having its peripheral portion clampingly confined between said shoulders to secure the disk to the housing, said disk having two pairs of substantially diametrically opposite slots opening to its periphery, said slots being substantially equispaced circumferentially, and said disk having a plurality of circumferentially spaced holes, each intermediate circumferentially adjacent slots, in which terminals are securable; a pair of flat insulative partition members disposed edgewise on the outer face of said disk, each in line with one pair of slots, and each having a medial slot opening to one longitudinal edge thereof in which a medial portion of the other partition memher is received, so that the partition members are thereby held with their surfaces substantially normal to one another and with a longitudinal edge on one partition member substantially coplanar with the corresponding edge on the other; and means for securing said partition members in place on the flat outer surface of the disk with the partition members substantially normal to said surface of the disk and extending between circumferentially adjacent terminal holes therein to preclude inadvertent contact between conductors secured to terminals in said holes, said means comprising a tongue at each end of each of the partition members projecting from said longitudinal edge thereof and snugly engaged in one of said slots in the disk, said tongues having retaining portions in said slots which are equal in width to the thickness of said disk and project outwardly to the periphery of the disk, said retaining portions on the tongues being clampingly confined between said shoulders on the housing.

References Cited in the file of this patent UNITED STATES PATENTS 1,532,098 Anderson Mar. 31, 1925 2,526,255 Milbank Oct. 17, 1950 2,623,087 Latta Dec. 23, 1952 2,650,973 Jacobi Sept. 1, 1953