US987985A - Switch. - Google Patents

Description

G. W. HART.

SWITCH.

APPLIGATION FILED JUNE so, 1910..

987,985. Patented Mar. 28, 1911.

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GERALD W. HART, OF 'WEST HARTFORD, CONNECTOUT, ASSIGNOR T0 THE HART MAN- UFACTURING COMPANY, 0E HARTFORD, CONNECTICUT, A CORPORATION OE NEW JERSEY.

SWITCH.

Specicaton of Letters Patent.

Patented Mar. 28, 1911.

Application tiled June 30, 1910. Serial No. 589,627.

To all whom it may concern:

Be it known that I, GERALD lV. HART, a citizen of the United States, residing at Wvest Hartford, county of Hartford, State of Connecticut, have invented ncertain new and useful Improvements in Switches, of which the following is a full, clear, and eX- act description.

My invention relates to improvements in switches, and has for its object to produce a small and compact switch for breaking a circuit without harmful sparking or arcino.

It is particularly designed for circuits having a voltage higher than 110 volts,

such, for inst-ance, as a 500 volt circuit or thereabout, which voltage in a switch of ordinary dimensions with no arc preventing means is liable to produce harmful results.

rThe following is a description of a switch embodying my invention, reference being had to the accompanying` drawings, in which- V Figure 1 is a plan view of the switch, the cover being omitted. Fig. 2 is a side elevation of the same. F ig. 3 is a vertical section of the same with the cover present on the line :U-x, Fig. 1. F ig. 4 is a plan and side elevation of a detail. F ig. 5 shows a plan view of the switch arm. Fig. 6 shows a detail of a stop block, latch and switch plate.

Referring more particularly to the drawings, 1 is a switch base of porcelain or other suitable insulating material.

2 2 are contact posts.

3 3 are base plates secured to the contact post and themselves secured to therswitch base 1 by screws in the ordinary manner.

rlhe contact posts carry spring contacts h1 -4, which are O-shaped punchings bent upon themselves, each having one side inserted in a slot in the binding posts at 5, the edges of the slot being upset to hold the contact member securely in place. lThe engaging portions of the contact members 4 lie within large slots 6 formed in the binding posts so as to not ext-end out beyond the binding posts but to coincide substantially with the axes of the posts. TWith this construction of binding post, the switch arml for a switch with a base of a given diameter can be made very much longer than it could be made if the contacts extended inward from the binding post toward the axis of the switch blade. The base plate 3 of the binding post has an inner extension 7 which is bent and screw-threaded so as to form a screwethreaded bore. The bores are each provided with a transverse perforation 8 connecting with holes 9 for the leading-in wire, which passes through the transverse perforation 8 and is secured by a screw 10 engaging screw-threads on the inner surface of the bore formed by the bent projection 7.

11 is the shaft of the switch mechanism having within it the spring 12, one end Of which is connected to a spring plate 13, and the other end of which is connected at 14 to a switch plate 14a. The shaft 11 carries a rotating member or switch arm carrier 15 secured thereto. To this rotating member are secured bushings 16, being separated therefrom by insulation 17.

18 is a switch arm carried by the bushings 16, which pass through the same, the edges of the switch arm tting loosely in recesses in the bushings so as to permit the switch arm to have considerable play, thereby enabling it to adjust itself to any variation in the position of the contacts 4.

The switch is provided with a stop block 18a and a latch 19 moving in a recess in the switch plate 14a, the latch being moved by a pinion 20 carried by the spindle 21, to which the handle 22, spring plate 13 and switch plate 14 are connected, thus producing a quick acting step-by-step switch mechanism of the general type shown in my Patent No. 753,881.

This switch as thus described, on account of the distance between the two pairs of contacts 4, has a larger throw and will therefore tend to more readily break a circuit without arcing when mounted on a base of given di mensions, than a switch with a shorter switch arm, such as would have to be used with contact posts having inwardly projecting contact members. There .is still, however, a liability that the arc will follow the switch arm or jump to the switch mechanism on the breaking of a circuit and produce damage. In order to prevent this injurious result, I place between the carrier 15 and the switch arm a thin circular sheet of insulating material 23, and above the switch arm 18 place a similar sheet 24 holding the two sheets together and clamped about the switch arm 18 by rivets 25. These two sheets move with the switch arm 18 and are provided with openings, which surround the bushings 16 loosely, so as not to interfere with the move- Les ment of the sheets 23, 2li, or the movement of the switch arm 18 relatively to the bushings. The ends of the switch arm 1S extend beyond the edges of the insulating sheets sutliciently to pass between the contacts et. The switch mechanism is inclosed in the usual cap 26 with a lining ot paper 27 to thoroughly protect it from arcing. wWith such an arrangement, when the switch is operated, the switch arm 18 moves away from the contacts quickly, and in its place opposite the contacts is substituted a pertion oit' the insulating disks 23, 2li. Moreover, a portion of the insulating disks 23, 24

is interposed in the direct path between the exposed ends of the switch arm and the contacts. TVith such an arrangement, the tendency to arc is very greatly reduced, and currents ot very considerable voltage can be broken without the danger of establishing injurious arcs. The construction is simple to manufacture and the operation is etlective.

/Vhat claim is:

l. In a switch, the combination of a quick acting switch mechanism, a carrier rotated thereby, a switch arm supported by said carrier but insulated therefrom, and sheets of insulating material immediately above and below said switch arm fastened together so as to be secured thereto and carried thereby, said switch arm and insulation being mov- `acting switch mechanism, a switch arm loosely carried thereby but insulated therefrom, sheets of insulating material above A and below said switch arm secured together so as to move with said switch arm and be carried thereby, said switch arm having ends extending beyond the edges oit' said she-ets.

y and contact posts carrying contacts adapted to engage the extremities ot said switch arm at points approximately in line with the axes of said contact posts.

3. ln a switch, the combination oit a quick acting switch mechanism, a carrier rotated thereby having projecting studs, switch arm loosely engaging said studs and sheets of insulating material immediately above and below said switch arm tasten-ed together so as to be secured thereto and carried thereby, said switch arm and insulation being movable relatively to said studs and carrier, said switch arm having its ends extending beyond the edges of said insulating sheets, and contacts engaged by said ends.

GERALD W. HART. 1Witnesses IDA M. HUNZIKER, L. S. JAMES.

Copies of this patent may be obtained for ve cents each, by addressing the Commissioner of latents, XVashington, I). C.

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