US1879349A - Relay contact - Google Patents

Description

p 1932- K. M; LEDEREIQ RELAY CONTACT Filed April 3, 1950 Patented Sept. 27, 1932 UNITED STATES PATENT KARL M. LEDERER, OF NEWARK, NEW JERSEY, ASSIGNO R TO WESTON ELECTRICAL INSTRUMENT CORPORATION, OF NEWARK,

JERSEY RELAY CONTACT Application filed April 3,

5 controlling relatively high currents.

An object of my invention is to provide a relay contact element having a bufling member or members, which contact element is simple, strong, inexpensive to manufacture and easily assembled.

A further object is to produce a relay contact element of the type including a resilient bufling member which is capable of carrying a higher current than other control elements of the same general type.

Still another object of my invention is the provision of a contact element in which a buffing member also serves to cause wiping contact between the contact element and the stationary contact members.

Other objects will be apparent from the accompanying drawing and the description thereof, in which drawing:

Fig. 1 is a plan view of the contact element.

Fig. 2 is a side view, partially in crosssection,

Fig 3 is an oblique view of the auxiliary contact member, and V Fig. ft is a fragmentary view showing the contact element in one of its closed circuit positions, together with a stationary contact member. The contact element comprises, in its preferred form, two members, a main contact member 1 in the form of a pointer cross and an auxiliary contact member 2.

The main contact member is formed by punching a member of the proper size and shape from a sheet of aluminum or hard drawn sheet copper. It is given the shape of a cross, of which one arm 2 constitutes the pointer or contact arm and the remaining arms 4, 5, 6, constitute balance arms to balance the weight of the pointer arm. 7 V

The auxiliary contact member 2 is made from contact material such as platinum, platinum-iridium alloy, silver alloy or equivalent material and is in the form of a channel from which a portion ofthe web has been removed. This construction provides 1930. Serial to. 441,411,

a short, channel having parallelfingers 7,

extendingtherefrom.

Th channeled portion 90f the auxiliaryli' contact 'memberisse'cured; by means of a rivet 10 to an' offset portion ll of the pointer arm 3 situated substantially midway'between the ends of; the pointer arm. The web portion of the auxiliary contact member is of, I

such size that the'flanges'engage the edges of the pointer arm at the oflset portion and the fingers extend along opposite sides of the as. e,

outerportion '12 of the pointer arm. The outer portion 12 of thepointer arm is re- I du'ced in si ze so that there is an appreciable space between the edges of the pointer arm auxiliary contact member.

The parallel fingers are made greater in width than the thicknessof the pointer arm so that satisfactory contact may be made be-' tween them and a cooperating stationary contact'member13. 'In order that the pointer armwi'll -be disposed symmetrically between f theiparallel fingers, the ofiset portion 11' is of such depth as to bring the center of the against the outer end 12 of. pointer arm 3, cone NEW JERSEY, 1A CORPORATION or NEW You and the sides; of the parallel fingers of the I V v 7f outerfportlon of the P01111781 arm opposite" twisting of the p tacting therewiththroughout a considerable area,becauseof:,the resiliency ofthe arm of the auxiliary-contact member. Current will then flow through the parallel finger 7 and the pointer arm 3. r

The parallel fingers 7, 8 being constructed of resilient material, will offer some resist ance to the movement of the contact element against the stationary contact member and will thus absorb most of the shock incident to element is in its plane of movement,thecontact element is relatively rigid and reinforces the thin contact fingers after it has flexed into engagement with the contact element.

The pointer arm is of relatively large cross-section and a good heat conductor. When it is forced up againstone of the parallel fingers and-contacts with it through a r ela-,v

tively large portion of the area, any'heat which may be developed at the point of contact between the parallel arm andthestatiom ary contact 'member is ilbSOIbGdllflllClfiCOIl-q ducted away and no harmful heating of the contact surfaces is possible.

It is apparent that the invention is particularly useful in the embodiment slrown above but isin no way restricted to that use but may be used in anytype of single or multiple contact apparatus where it'is-desired to have a contact member provided with buifing means and capable of carrying relatively high currents. Iclaim: v- .1. In a relay contact element for cooperation with a fixed contact element, the combi- I nation with a" relatively rigid main membeif of cruciform'sha-pe havingone arm reduced in size adjacent the endlthereof, of an auxiliary'member of flexible material securfedto the larger portion of said arm and. havinga pairof parallel fingers extending along and spaced from the reduced, portionoflsaid arm, the end portions of saidfing'ers being disposed to lie against. the reduced portion ofsaid'arm when saidelement cooperates with a fixed contact element. l, 1

2. In a relay contact element,-the combina: tion-with an elongated,thin-, sheet-metal main member having an offset portionintermediate its ends and reduced portion-adjacent one end, .of an auxiliary member ofhighly flexible materiallhaving the formofa chan: nel with aportion of :the web remo-vedlto provide a pairof'parallel fingers,-an d means for securing the web portion of. saidauxih iary member to the oflsetlportion of-said main member ,witlrsaid fingers extending along and normally spaced from-thereduced portion and positioned; .to contact with 1 the reduced portion when said contact element abuts a; stationary contact velement, whereby said members mutually reinforce one anv In testimony Wher\eof,.I aflixmy signature. KARL M. LEDERER. v

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