US993961A - Electrolytic lightning-arrester. - Google Patents

Description

E. E. F. UREIGHTON. ELECTROLYTIC LIGHTNING ARRESTER. APPLIOATION FILED 001. 11, 1907. RENEWED 00125, 1910.

Patented May 30, 1911.

I Ifivehtor: Elmer BF. Creighton,

Witnesses:

nnmnnn r. cnnrcn'ron. or SCHENECTADY, NEW YORK, 'ASSIGN on To GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.-

v'r innc'rnomr rrc nrsnrnmcmmmsrnaz specificationot Letters Patent. Patented May 30, 1911.

Application filed October 11, 1907, Serial No. 3'.- )6,910. Renewed October 5, 1910. Serial No. 585,516.

To all whom it my concern:

' 6 Be it'known that I, Emunn E. F. Canton- TON, a citizen of the United States, residing at Schenectady, county of Schenectady, State of New York,- have invented certain'new' and useful Improvements in Electrolytic Lightning-Arresters, of which the following is a specification.

This invention relates to devices for protecting high tension'transmission lines from. the destructive efiects of abnormall potential, especially that due to ligtn'lng. On a transmission. line the lightning disturbanc'es may be divided into two classes advisable to place an aluminum arrester in according tothe duration of. the disturbancez'. e., whetherbrief or sustained; They may be termed respectively transitory lightning and continuous lightning.- Aflightning ar- 'rester of the aluminum type wears -out if subjected toa continuous flow oftcurrent, so. that fromrthefstandpoint of economy it is a circuit containing a normally open spark gap. Under these conditions, if a lightning discharge istransitory it will spark across thegap, and if the gap is provided with arcextlnguishing burns, the dynamic arc 01- lowing the lightning will rise thereon, break and open the circuit. But'if the lightning is continuous the arc will be continually reestablished as rapidly as it is extinguished. Inasmuch as the continual play of arcs up the horns is in many cases objectionable, it is desirable to provide means for closing the gap during such time as the continuous lightning is on the line.

The object of my invention is to provide a discharge path in which a current limiting device, such as an aluminum cell lightning arrester, has a spark-gap in series with it, and some current' responsive means, such as a time limit switch, which closes said gap when the lightning is continuous. The time element maybe secured by any suitable device, such for example, as a dash-pot or" a thermostat, but in any event it is designed to be unaffected by a transitory discharge across the gap. In other words, it must not close the switch during the time that the first one or two arcs are traveling to the tips of the horns. If, however, several dis charges follow in quick succession, the switch will close, and at the same time sound an alarm to notify the attendant.

In the accompanying drawing, Figure 1 is a diagrammatic representation of my invention, the time element being a dash-pot; and Fig. 2 shows another embodiment in which the time element is thermostatic.

In both figures an aluminum cell lightning arrester 1 is connected to ground at 2 and. to

line at 3 through a normally 0 en spark gap 4 provided with arc-extinguis ing horns 5. An electric alarm bell 6 is also included -in the circuit. The aluminum cell arrester is the same as that disclosed in Patent;No. 923,024, granted to me May 25, 1909, and

need not be described in detail. v

The spark gap is provided with a time limit switch for closing it when the lightning becomes continuous. In Fig. 1 two contacts are arranged in a shunt around the gap, and a bridging contact 8 is mounted on a lever 9. An elect-romagnet or solenoid 10 is placed in circuit 'with thealuminum cell,"and-its armature or movable core 11 is connected with said lever 9,.preferably by means of a spring.12 at a point adapted to pass the fulcrum of the' lever when the core is attracted by the coil'lO. The core carries a piston working ina dash-pot 14.

' Inasmu' h' as the solenoid 10.and the magnet coils in thebell 6 introduce considerable inductance into" the circuit which interferes with the' free discharge of small static charges, an aluminum cell 15 is shunted around the elect-romagnet 10 and a second aluminum cell 16 is placed in shunt to the bell. These permit the high frequenc static charges to pass freely to groun Moreover, when the coil 10 becomes energized by the dynamic current following a' lightning discharge it tends to move the pore,

and if the dischar eis continuous forseveral seconds, the retar ation of the dash-pot will finally be overcome. The instant the spring is carried past the fulcrum ofthe lever, the latter will'be suddenly moved and the contact 8 will close the shunt around the gap. This stops the processionof arcs up the horns, and the discharge takes place through a closed circuit. Thev ringing of the alarm bell notifies the station attendant that there tention. The aluminum cell arrester is de signed to carry the current for such length of time as may be necessary for. the attend- 'is a defective circuit which requires his atbars 17 18 of different materials having different coefficients of heat expansion. Thus the rod 17 maybe of brass and the rod 18 of iron, or evenof some non-conducting material like Wood. 'The rods are pivoted together at one end, and their other ends are pivotally attached to a latch 19, at different points thereon. The latch upholds one end of a weighted lever whose other arm is "connected, as by .ie link 21, with a pivotedswitch 22, adapted to close the spark gap when the'lever 2O falls.

The passage of current for a given interval of time through the-rod 17 will heat and expand it lengthwise sufliciently to .push the latch out from under the lever 20 and let it drop, as shown in dotted lines, thereby closing the switchand ringing the alarm 6; which in this case, also, may have the aluminum cell shunt 16.

In accordance with the provisions of the patent-statutes, Ihave described the principle of operation of my invention-together with the apparatus which I now consider to represei'it the best embodiment thereof; but I desire to have itunderstood that the ap- 'paratus shown is only illustrative, and that a device for closing said gap co'mprrmg a time-limiting element. i

3. The combination with an aluminum cell lightning. arrester,'of a series spark gap, a SWltClkfOl: closing said gap, and a device for operating saidswitch comprising timeele ment means responsive onlyto a continuous discharge of current.

1. The combination Wi'tlian aluminum cell lightning arrester, of a series spark-gap provided with a horn arc-extinguisher,a switch f for closing said gap, and'means for closing said switch only after the passage of curr'ent across said gap for severa seconds.

'5. The combination with an aluminum cell lightning arrester, of an alarindevice in 'cir cuit therewith, a spark-gap, and nieans :for

closing said spark gap in case the lightning is continuous. v

6. The combination with an electric emergency discharge device, of an al arm'device in circuit therewith and an aluminum condenser cell in shunt with said alarm device.

7. A discharge path for abnormal poten i tial comprising a current limiting device-,0, spark gap in series with said dev ce,and'ai tomatic means for bridgingf said gap responsiveonly to sustained discharge through saidpath. i

8. A discharge path for abnormal potential comprising a current limiting device, an.

indicator which obstructs a free discharge a through said path and an electrolytic con I denser connected in hunt to said indicator.

7 In witness whereof, I have hereunto set my hand this 10th day of Qctober,1 0' 7. ELMER ELF, onn ei 'ron;

Images