US860726A - Surface-contact electric railway. - Google Patents

Description

No. 860,726.. PATENTED JULY 23, 1907.-

W M. BROWNZ Y SURFACE GONTAGT ELECTRIC RAILWAY,

APILIOATIOF nun JULY 29. 1904.

$ .4 TTORNEY.

TH: ncmus PETERS cm. wast-" 4010". n. c.

UNITED STATES PATENT OFFICE.

WILLIAM MILTON BROWN, OF JOHNSTOWN, PENNSYLVANIA, ASSIGNOR TO THE LORAIN STEEL COMPANY, A CORPORATION OF PENNSYLVANIA.

SURFACE-CONTACT ELECTRIC RAILWAY.

Specification of Letters Patent.

Patented July 23, 1907.

Application filed July 29,1904. Serial No. 218,656.

To all whom it may concern:

Be it known that I, WILLIAM MILTON BROWN, of Johnstown, in the county of Cambria and State of Pennsylvania, have invented a new and useful Improvement in Surface-Contact Electric Railways, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings, which form a part of this specification.

My invention has relation to surface contact electric 1O railways, and is designed to provide means for preventing maintained arcs in the contact boxes after the passage of a car. These arcs sometimes occur by reason of a heavy surface leakage from the contact box to an adjacent track-rail or other conductor, which is sufficient to maintain an arc across the members of the switch after the latter has opened.

My invention consists in providing means whereby, before the car leaves the box, any are which tends to hang therein is immediately short circuited and extinguished.

The accompanying drawing is a diagrammatic view illustrating my invention.

A, A, & A designate the-switch devices of three adjacent contact boxes or devices, and a, a, a the surface contact plates thereof.

13, designates the supply conductor or feeder, having branches 1) leading to the boxes.

C designates the usual current collecting skate, shoe, or trolley carried by the car; D, the car magnets, and

E, the car motor.

R designates a track rail.

F is an auxiliary skate or shoe, placed behind and in line with the shoe D, and electrically connected thereto, or with the circuit thereof, by a conductor such as G.

The purpose of this shoe is to provide means for shortcircuiting any are which may form in the boxes, and the operation is as follows-Supposing the car to be passing in the direction of the large arrow, the shoe 0 has left the contact a of the contact device A, and is on 40 the contact a of the box A. If now from any cause, a heavy surface leakage occurs from the plate a to the rail R, or other adjacent conductors, as illustrated by the chain of small arrows, an arc may tend to be maintained at S, between the separated contacts of the switch A. As soon, however, as the auxiliary shoe F contacts with the plate A, another path is established for current to supply this leakage, and this path being of very slight resistance compared to the resistance of this arc, it is evident that the current will immediately take the new path, and the arc will be extinguished, being, in effect, completely short circuited. When the shoe F leaves the plate a, the circuit is simply broken at the surface of said plate. The are, being once broken, will not reform until another car passes. Any suitable indicating device may be placed in the conductor G, for the purpose of locating the boxes where leakage occurs.

It is usual to make the car magnets somewhat longer than the collecting skate or shoe G in order to hold the switching devices of the boxes closed until the shoe ceases to take current from the box. The auxiliary -skate or shoe should, therefore, be placed sufiiciently behind the car magnets so that the latter will cease to hold the switch closed before the auxiliary shoe makes contact with the plate. Said auxiliary skate is, as shown, also separated from the main skate or shoe by a sufficient space so that there is a time interval at each surface contact during which neither shoe is in engagement with the said contact. In this manner, no current is passing through the contacts at the time the magnet ceases to act thereon. V 1

My invention is obviously applicable to various forms of surface contact systems, and is susceptible of various modifications, without departing from the spirit and scope of my invention I do not therefore limit myself to the particular embodiment which I have herein shown and described.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent is:

In a surface contact electric railway system, the combi- 8O nation with contact boxes provided each with a movable circuit-closing member therein, and with a surface portion or cover, a car magnet for acthating the circuit closing members, and a current-collecting shoe arranged to contact with the surface portions or covers of the boxes, and to receive current therefrom, of means for short-circuiting arcs which may hang in the boxes after the passage of the magnet and shoe, said means consisting of a shorter auxiliary shoe in rear of the main collecting shoe, and an electrical connection from the auxiliary shoe to the main shoe, the auxiliary shoe being spaced from the main shoe and also from the magnet to provide a time interval at each contact, after the car magnet has ceased to act, when the contact is not engaged by eithershoe; substantially as described.

In testimony whereof, I have afiixed my signature in presence of two witnesses.

IVILLIAM MILTON BRO\VN.

Witnesses E. ii: Cmsswnnn, MAn'rIx ALDl-ZRWICK.

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