US528900A - Frank g - Google Patents

Description

(No Model.)

P. G. BOLLES. ELECTRIC SWITCH.

Patented Nov. 6, 1894.

i i a.

UNITED ,ATENT Fries.

FRANK G. BOLLES, OF WVASHINGTON, DISTRICT OF COLUMBIA, ASSIGNOR OF ONE-THIRD TO PAUL EATON, OF SAME PLACE.

ELECTRIC SWITCH.

SPECIFICATION forming part of Letters Patent No. 528,900 dated Novemberfi, 894.

Application filed March 27, 1894.

To all whom it may concern.-

Belt known that I, FRANK G. BOLLES, a citizen of the United States, residing at Washington, in the District of Columbia, have invented certain new and useful Improvements in Switches for Controlling Electric Circuits; and I do declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to the letters of reference marked thereon, which form a part of this stationary terminal, and between which. the

movable terminal or blade enters. When the switch is of large dimensions, it is sometimes difficult to open it, owing to the great friction between these terminals, and the slowness with which the switch may have to be opened increases the danger of injurious arcing be tween the terminals.

My invention consists in a device for tightening the contact between the terminals of an electric switch after the switch is closed, in order to reduce the resistance and insure a more perfect electrical continuity of the circuit. r i

The invention is capable of being carried out in a variety of ways, and is applicable to utilized to effect the tightening of the contacts. In order to do this, the handle must be movable relatively to the movable contact or the blade of the switch, and this movement $erial No. 505,298. (No model.)

verse to the movement of the movable contact, or in line therewith. It may be applied to one or more contacts, and in the latter case, they may be operated simultaneously or separately as desired.

In the accompanying drawings, Figure 1 is a perspective view of one form of switch embodying my invention. Fig.2 is an end elevation thereof, showing the contacts not tightened. Fig. 3 is an end elevation on a large scale, showing the contacts tightened. Fig. 4 is a side elevation of Fig. 3. Fig. 5 is aside view of the end of the handle. Fig. 6 is an end elevation of a modified construction. Fig. 7 is a side elevation thereof. Fig. 8is a side elevation of a second modification.

The base A is of some insulating'material, I

such as slate. The bifurcated block B serves as a support or fulcrum for the movable knife blade contact C, which is shown hinged on a transverse bolt D. Passing transversely through the free end of the blade C is a bolt E which is rigidly fastened in place, as by the set screw 0. Thestationary contact is a bifurcated block F having space enough between its arms to receive the blade C which fits snugly therein, to close the circuit, the line terminals being connected to the blocks B, F. Each arm f of the forked block F is notched to receive the bolt E.

On the projecting ends of thebolt is fulcrumed the forked handle G, the yoke of the fork being wide enough to pass down outside of the arms f. The bolt is also equipped at one or both ends with clamping or tightening devices, adapted to be operated by turning the handle, and serving to clamp the arms f tightly against the blade C, thereby greatly improving the electrical contact and reducing the resistance of the circuit.

In Figs. 1 to 5, the ends of thehaudle yok are shown as provided on theirouter faces with inclined surfaces or planes, preferably two, constituting the cams g g. In contact with these are washers H, each havinga corresponding double cam, and locked to the bolt by a spline h entering a keyway in the bolt.

Nuts I engaging with the screw-threaded ends of the bolt enable the washers to be adjusted toward the arms fin order to increase the clamping action or compensate for wear. Since the washers I-I do not turn on the bolt, there is no tendency to turn. the nuts when the handle is moved.

The handle stands normally as shown in Figs. 1 and 2, with the abrupt shoulder g? at the ends of the cams g g abutting against the corresponding shoulders in the washers, and preventing the handle from being moved farther back. Forward movement is, prevented by a pawl K pivoted to the knife blade 0 and engaging with a pin 9 on the handle. A spring is may be used to hold the pawl in engagement if desired.

The operation isas follows: When the movablecontact isswung down, it enters between the arms f, and closes the circuit. At the sameztime the pawl islifteclolf the pin g by striking a stop F risingadjacent to the block armsf tightly against the blade C. Itwillbe seenrthat only avery slight inclination: of the cam surfaces is necessaryto causea-powerful clampingaction. To open the switch thehandle is lifted, until theshoulders ofi'the cams: strike, when the parts willbe soloosenedthat theycan be easily separated, and the pawl K dropping down over the pin as the blade is liftedl If desired, the bolt D on which the blade is hinged maybe fittedwith stationary washers Hf havingcam surfaces, anda yokeG' similarly. provided, thezyoke being connected by alink L with thehandle G, so thatthe handle operates a clamping device at each end of the movable contact.

In" themodification shown in Figs. 6 and 7, the handle yoke engages with two nuts M, the screw-threads on the ends of the bolt E being right-and left-handed respectively, so that themovement of the handle screws the nuts toward each other, and causes them to clamp the arms f against theblade O. The nuts have polygonal peripheries fitting polygonal holes in the: handle yoke, to permit them to be adjusted.

In the modification shown: in Fig. 8, the blad'eG closes on aV shaped stationary contactN, and the handle has one or more hooked cams 0 to engage with a stationary post P and'forcethe blade down tightly into the contact N.

These are but three of many modifications of my basic idea,and indicate that it maybe carried out in a number of different ways without departing from the spirit of my invention.

Havingthus described my invention, what I claim as new is.-

1. A switch for controlling electric circuits,

having a fixed contactand. a movable contact, an operating handle on the movable contact, and movable relatively thereto, and a clamping device operated by an independent movement of said handle for tightening the contact between the fixed and. movable contacts after the circuits are closed, substantially as described.

2. A switch for controlling electrical circuits, provided with a clamping device to tighten the contact between its movable and stationary parts, said device being operated by the switch handleindependently of the movement which it imparts to the movable portion of the switch, substantially as described.

3. A switch for controlling, electrical cirj cuits, having its movable contact provided with a relatively movable handle, and. a clamping devicefor tightening thecontact, 5 operated by said.handleindependently ofthe movable contact, substantially as described.

4. A switch for controlling electrical circuits, having its movable contact provided with a relatively movable handle, astationary contact with which the movable contact engages, and a clampingdevice operated by said handle independently of the movable contact and serving-to force theeontactsto j cuits, having its movable contact provided. with a relatively movable handle, and a transverse bolt, and a clamping device movable axially of said bolt andoperated by said handle, serving to tighten the contact. between the movable and stationary parts of the switch, substantially as described.

7. A switch for controlling electrical cir-' cuits, having its movable contact provided with a relatively movable handle and atransverse bolt, and a clampingdevice comprising two inter-operating inclined planes one of whichis movable bysaid handle, saidclamping deviceoperating to tighten the contact, substantially as described.

8. A switch for controlling electrical circuits, having its movable contact provided with a relatively movable handleand a transverse bolt on which said handle is f-ulcrumed, and two stationary washerson said bolteach having one or more cam surfaces to cooperate with similar surfaces on: the end of the handle, substantially as described.

9. A switch for controlling electrical circuits, having its movable contact provided with a transverse belt, a handle. having a ICC forked yoke fulcrumed on said bolt, and provided with cam surfaces and shoulders, washers splined on said bolt and having cam surfaces cooperating with those on the yoke, and nuts on the bolt to adjust the washers, substantially as described.

10. The combination with the stationary bifurcated contact block, of the movable contact blade, the transverse bolt, the forked handle fulcrumed thereon, and carrying the cam surfaces, the stationary cam faced washers on the bolt, the pawl pivoted to the movable contact, and the pin on the handle, substantially as described.

11. In an electric switch, the combination with the movable contact,,of a handle hinged thereto, and a locking device for locking the handle to the contact, substantially as described.

12. In an electric switch, the combination with the movable contact, of a handle movable relatively thereto, a locking device for lockingthe handle to the contact, and means In testimony whereof I affix my signature in 0 presence of two witnesses.

F. G. BOLLES.

Witnesses:

PAUL EATON,

W. H. BENTLEY.

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