US585185A - Henry middlebiiook crane - Google Patents

Description

(No Model.)

H. M. CRANE. EARTH CONDUCTOR 0R GROUND WIRE ATTACHMENT.

Patented June 29, 1897.

fiibcesses Iuvenl'or.

/ m WWI/I ful adjunct to the protector-ground.

contiguous turns round the pipe and to at- NITED STATES PATENT Fries.

HENRY MIDDLEBROOK CRANE, OF BOSTON, MASSACHUSETTS, ASSIGNOR TO THE AMERICAN BELL TELEPHONE COMPANY, OF SAME PLACE.

EARTH CONDUCTOR OR GROUND-WIRE ATTACHMENT.

SPECIFICATION forming part of Letters Patent No. 58 5,185, dated June 29, 1897.

Application filed May 10, 1897. Serial No. 635,873. (No model.)

To all whom it may concern.-

Be it known that-I, HENRY MIDDLEBROOK CRANE, residing at Boston, in the county of Suffolk and State of Massachusetts, have invented certain Improvements in Earth Conductors or Ground \Vire Attachments, of which the following is a specification.

The earth is employed in association with telegraphic, telephonic, and other kinds of electric circuits both as a return-conductor and as a discharge-conductor for lightningarresters and similar protective devices.

In either case it is customary and highly convenient to attach the wire leading from the circuit or protective'appliance to a metal gas or water pipe, for by reason of the extensive ramifications of these pipes of gas and water systems a very large conductor-surface exposed to the crust of the earth is thus made available.

The necessity of a thoroughly-efficient connecting device especially in the protector association, has lately become very manifest.

Prior to my invention the method of attaching the earth conductors to the gas and water pipes has been to wind the copper wire in many tempt the formation ota homogeneous electrical union of the said pipe and wire by soldering.

Soldering is a difficult process in places where ordinarily ground-wire connections have to be made, and experience shows that it is often slurred and imperfectly done, and in such cases this mode of connection, never thoroughly trustworthy, is very inferior and cannot be relied upon as a safe and success- The object of my invention is to provide a suitable connector for easily and conveniently attaching the ground-wire to the gas or water pipe, which connecting appliance shall also be perfectly trustworthy as a good electrical connection of low resistance, shall be perma nent in the perfection of its attachment, and shall likewise be easily detached if disconnection is required.

My connecting appliance consists of a metal angle-piece with slots in one of its sides and a tapped hole, to which is fitted a tightening set-screw, in the other. A strip of metal is attached by soldering or otherwise to the tapped side of the angle-piece, being tapped or slotted for the passage of the screw.

The metal strip is preferably formed of tinned brass, and the bracket or angle-piece may be a punching and brass also.

To use such a connector in attaching the ground-wire to the pipe, the latter is carefully cleaned and brightened, the strip of metal is 60 passed round it and looped through the slots in the angle-piece. On setting up the screw the strip is drawn about the pipe as tightly as desired, and an excellent and permanent electrical connection is made. The strip of 6 metal can be as long as may, in each individual case, be convenient, and the ground-wire is secured to it by riveting or soldering or by a binding-screw, as preferred.

Of course all screws employed in this form 7 o of connection may be fitted with jam-nuts.

' In the drawings accompanying this specification, Figure 1 shows the connecting appliance with the brass strip looped through the slots of the angle-piece, the conductingwire being brazed or soldered thereto. Fig.

2 is a View of the same applied to a gas or water pipe and provided with a bindingscrew attachment for the conducting-wire. Fig. 3 is a perspective view of the bracket or angle-piece detached; and Fig. 4 represents a portion of an electric circuit provided with protective apparatus, the ground-wire and connecting appliance of my invention being clearly shown.

A is the conductor-connecting appliance; B, its bracket or angle-piece having slots at and b and a set-screw S, preferably supplied with a jam-nut s.

R is the strip of brass or other metal or alloy soldered, brazed, or otherwise attached to the said angle-piece and slotted or perforated for the passage of the screw S.

In a connecting appliance or grounding attachment of this class for pipes which I have made the end of the strip is doubled back on itself, soldered to the outer surface of the unslotted face of the bracket,and then passed over the point of the set-screw and threaded through the slot at in the other face or close I00 to the apex of the angle of said bracket.

The earth conductor or ground-wire to may be soldered orbrazed to the end of the metal strip .R, as at so, or, if desired, the latter may be provided with a binding-screw C, preferably furnished (like the set-screw S) also round the pipe, drawn again through the same slot a reversely, and then' baekwardly through the second slot 1) of :the angle-piece and bent backward therefrom. This being done it only remains to set or turn up the screw S, when the brass strip is strongly tightened up around the pipe and an excellent'eleetrical connection with the said pipe is thus provided. The position of the screw may then be seen red by the jam-nut .9. If a soldering connection is wanted for the groundwire 11', it may, if desired, be made before the connector is applied to thepipe, and so made will'avoid the chance of poor work due to inaccessibility.

In Fig. l, \V is the conductor of the main circuit and is shown as leading through a fuse-protector jand a plate and air space the water-pipe P, to which it is attached by means of the connector appliance A,which connects with the wire w through the binds ing-screw O and with the pipe 1 through the metal strip R, angle-piece 13, and set-screw S, constituting the said appliance A.

The arrangement is very efficient, almost the entire circumferential surface of the pipe being in contact with the metal strip, thus making a first-class electrical connection and preventing the ingress of moisture and the resulting corrosion, which otherwise might be expected. The connector has but three essential parts, all of which are simple, inexpensive, and easily made, and it can be attached without taking it apart, thus not only facilitating the process of attachment, but avoiding the chance of the parts loosening or being lost.

I am aware that grounding clamps or connectors, broadly considered, are not new, and I consequently make no claim to such a device per 3c; but

I (10 claim- 1. A connectorfor attaching a ground-wire, or an electric circuit or protector earth conductor, to a gas or water pipe, consisting of a metal angle-piece having slots as described, and a threaded perforation through one of its faces; a metal strip secured at one end to the outside of the perforated face, arranged to pass twice in opposite directions through the first slot, and once through the other, and adapted to surround the said grounding-pipe between the points passing the said first slot;

and a tightening set-screw associated with the threaded perforation of the said anglepiece, and impinging upon the metal strip between its fixed end and the nearest slot thereto, substantially as set forth.

2. he combination with the ground or earth wire ofan electric circuit or protective device; and a metal pipe or red in permanent earth connection, such as a gas or water pipe; of an attachment comprising a metal bracket or an gle-piece having slots as described in one of its sides,and ascrew-threaded hole through the other, a metal strip at one end secured to the said angle-piece, andits other end. to the ground-wire, and arranged to pass through the-first slot and back, and then through the second, successively, and to embrace the said rodor pipe by that portion of its length be tween the said two passages of the first slot; together with a tightening-screw passing through the threaded hole of said an gle-piece,

and adapted to bear atits point on the said strip; the said attachment forming the terminal of the said earth-wire, and constituting a con venienrly-applied and efficient electrical connection betweenthe said earth-wire and the said permanently-grounded pipe or rod;

substantially as and: forthe purposesspecitied.

. A connectorforattaching an electric conductor to a gas or otherpipe, consisting of a bent or curved metal base slotted as described, and provided with a tightening-screw at one end thereof, a metal band fixed by one end to the said base, and extended over the point of said screw through the first of said slots, backwardl y and forwardly in succession, and adapted to be returned through the second slot, and to be secured over the end of the base, as and for the purpose set forth.

4. A connector for attaching an electric conductor to a gas or other pipe, consisting of a metal band looped around the pipe, in combination with a holding or securing device through which said loop passesand whereby it is held in close contact with the pipe, substantially as described.

In testimony whereof I have signed my name to this specification, in the presence of two subscribing witnesses, this 3d day of May, 1897.

HENRI )iIllDLliliIlOOK CRANE.

\Vitnesses:

JosEPH A. GATELY, Tnonas D. Lockwooo.

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