US1919065A - Switch - Google Patents

Description

y 1933- E. H. JACOBS 1,919,065

SWITCH Filed Sept. 16, 1929 fwmzw i 4 177265; i k/@6055 Patented July 18, 1933 UNITED STATES PATENT OFFICE ERNEST HQJ'ACOBS, OF RIVER FGREST, ILLINOIS, ASSIGNOR TO ELECTRICAL ENGINEERS EQUIPMENT CO., OF MELROSE PARK, ILLINOIS, A CORPORATION OF ILLINOIS SWITCH Application filed September 16, 1929.

This invention relates to high tension air break switches in general and more particularly to the construction of arcing horns for such switches.

It is one of the objects of the present invention to provide an arcing horn which shall have an inherent tendency to reduce the current flowing therethrough during the switch opening movement, that tendency increasing as the length of arcing horn included in the circuit increases. The arcing horn is preferablymade of galvanized iron pipe with a hard copper tip at theend thereof where the circuit is broken. The iron pipe has a high reactance and thereby tends to reduce the current flowing through the circuit. If desired a steel tube may be placed around each of. the arcing horns ofan open air break switch for producing the same result. The steel tubeis placed around each horn except at the arcing tips thereof. The outer tube is made shorter than the horn so that the break takes place at the tip of the hard copper horn and not on the steel tube.

The steel tube acts in the nature of a reactance-for heavy current and permits the into and out of engagement therewith. Each contact is provided with an arcing horn. The arcing horn associated with the main contact is pivotally mountedand is adapted to be swung from its normal position during the switch opening movement. This swing ing movement is brought about by the arcing horn that is associated with the movable contact making member,- the arcing horns sliding along one another until the horn associated with the movable contact slides off of the other horn, whereupon the two horns separate with a snap action.-'

In order to acquaint those skilled in the art with themanner of constructing and op- Serial No. 392,921.

crating switches of the present invention, reference may be had to the following specification taken in conjunction with the accompanying drawing forming a part thereof, from which it is believed that the manner of obtaining the above and further objects of the present invention will be apparent.

In the drawing Fig. 1 is a side elevational view of a switch constructed in accordance with my invention. the full lines showing the switch in the closed position, the dotted lines showing the open position of the parts, and the dot-dash lines showing an intermediate position of the parts;

Fig. 2 is a view in partial section of the arcing horn associated with the stationary main contact;

Fig. 3 is a side View of the arcing horn associated with the main movable contact; and

Fig. is an end view of the arcing horn associated with the movable contact.

Referring now more particularly to the drawin the switch herein shown is of a construction such shown in my pending applial l lo. 334,090, filed January 21, Hing therefrom only in that the arcing horns of this switch are of my improved construction. Ref rence may be had to the above referred to application for a more complete description of the switch herein shown.

Referring now to Fig. 1, the common base member 1, which is preferably a channel bar in inverted position, supports at its opposite ends stationary insulators 2 and The stationary insulator 8 has its pedestal 4c mounted directly on the inverted web of the channel bar 1, and the insulator 2 has its pedestal 5 IVhilc in Fig. 1 the elements for a single phase only appear, it is to be understood that directly back of the switch shown in Fig. 1 there are placed two identical units for a three-phase line, the channel bases 1 being suitably connected together by a framework on which the gang switch is mounted.

The cap 7 of insulator 3 contains a base and terminal member 8 bolted thereto. This base and terminal member 8 has a pivot pin 10 mounted thereon. The base and terminal member 8 is also provided with a laterally depending arm 11 to which there is connected a terminal lug for receiving the phase conductor 13, which conductor may be gripped to the arm 11 by any mechanical means, such as the U-bolt 14.

The front part of the terminal lug is bolted to the arm member 11 with the ends of flexible ribbons 17 disposed between it and the arm 11.

The stationary insulator 2 has a cap member 18 which supports a bracket member 19 thereon. The line phase conductor 20 is mechanically bolted to and in electrical contact with the bracket member 19.

A flexible copper or other suitable ribbon 21 is bolted between the terminal lug of the line phase conductor 20 and the bracket member 19, and carries the currentfrom the phase line 20 to suitable contacts within the housing 31.. The contact construction within the housing 31 comprises a pair of contact shoes to each of which. the flexible braided conductor 21 is suitably secured.

The housing 31 is provided. at its top with a pair of upwardly projecting lugs or ears 32, in which is mounted a pivot pin 34. A split bracket member 35 swings about the pivot pin 34 and supports a movable arcing horn 36. The horn 36 is rigidly held in the bracket member 35 by means of a pair of bolts 37. A spring biases the horn 36 to the posit on shown in Fig. 1, a stop 38 limiting the movement of the arcing horn in that direction. The projection 39 on the bracket 35 limits the extent of rotation of the arcing horn in the other direction. A bracket 41 at the top of the housing supports a pair of spring members 42 made of bronze or other suitable metal. 'The spring clips 42 embrace the end of the bracket member 35 and are outwardly flared at their ends 43 for guiding the bracket member into position.

The movable contact assembly, shown more particularly in Fig. 1, is of the same general construction as that of the appli cants prior application, Serial No. 266,167, filed March 31, 1928. A bar 44 is hinged at its rear end on a pin 45, which pin is supported at opposite ends of the bar 44 on a pair of links 46. Instead of employing a pair of links, a single link may be utilized for the reason that the bar 44 secures an independent guiding motion from a movable insulator 47. The flexible ribbon 17 is bolted or otherwise secured to the bar 44 at the point 4, whereby the current carried by the switch is shunted around the pivots 45 and 10.

Thelower end of the links 46 are hinged on the pin 10. It will be observed that the upper end of the link 46 rises about its center nelaoes 10 as the switch is moved to the open position indicated in dotted lines.

The rocking insulator 47 has its pedestal 51 clamped by means of a suitable split clamp to a hollow square shaft 52. The shaft 52 is supported in a bearing 53 through the intermediary suitable journal blocks.

Reference may be had to my pending application, Serial No. 334,090, above referred to, for a more complete description of the hearing structure. The square shaft 52 is connected as by a suitable clamp with an operating lever 54 which may be operated by means of a suitable operating rod 55.

The insulator 4-7 has an insulator cap 57 on which there is bolted a bracket 58, this bracket being bifurcated at its upper end to embrace the side of the contact bar 44, a pivot pin 59 being passed through the upper end of the bracket and through the contact bar 44.

The free end of the contact bar 44 is controled by the movement of the bracket 58 about the square shaft 52 as a center, and it will be seen that, within the limits of motion indicated between the full lines in Fig. 1 and the dotted lines therein, the outer end 43 of the arm 44 move from a substantially horizontal position to a position which is more nearly vertical. The relation of the length of the arms 44, 46, and the respective lengths of the bracket 58 are essential to secure this acti on. It will be observed that the bifurcated bracket 58 is split down to substantially the base thereof so that the end 43 of the arm 44 passes within said bracket when the switch is in the open position, as indicated in the dotted lines.

An arcing horn is rigidly held in a bracket 66 which is suitably secured to the bracket 58. The arcinghorn comprises a tube or pipe 66 of galvanized iron or of steel. Into one end of the tube a copper horn 67 is inserted. The copper born 67 ma ,if desired, extend clear through the steel tu e 66 to the end thereof, or it may extend only a short distance into the tube. The horn 67 is shown as extending only a short distance into the tube, terminating at 68.

The tube 66 and the horn 67 are soldered or otherwise suitably secured together. The portion 67 of the horn is made of copper or other suitable conducting material and is bent into the form of a V as shown in Fig. 4.

The arcing horn 36 likewise comprises a tube 70 which may be of steel or of galvanized iron into the end of which a hard copper areing tip 71 is inserted. The arcing tip may of course be of bronze or other suitable conducting material. The tip 71 extends into the tube being suitably secured thereto b soldering and pinning as indicated at 7 If desired, the arcing tip may extend clear through the tube.

Upon movement of the insulator 47 from involving both of those the switch closed to the switch open position, the horn 65 engages the horn 36 before the main contacts within the housing 31 have separated. As the switch is further opened, the horn 36 rides within the V-shaped portion of the horn 65, this V-shaped portion sliding along the arcing horn 36 which horn is drawn about pivot 34 in a clockwise direction as seen in Rig. 1. Upon continued opening movement of the switch, as the V-shaped porti m r des off of the end of the arcing horn 36 as shown in the dot-dash lines in Fig. 1, the arcing horn 36 is released and, under the action of a. spring coiled about the pivot 34, is snapped back to the position shown in full line in Fig. 1. This rapid snapping action prevents the formation of a dangerous are upon the separation of the arcing horns. The continued movement of the switch brings the parts into the full open position as shown in the dotted lines in Fig. 1.

The high reactance of the steel or galvanized iron tubes and 66 of the arcing horns tends to limit the current flowing through the switch during the switch opening movement as a result of which the switch may be used to open a much greater amount of power than would be possible the horns were all of copper or other high conducting material.

The interrupting capacity of a switch such as is shown in this application is determined by number of factors, amongst which may be mentioned the speed. at which the horns separate to interrupt the circuit, and the amount of reactance that is introduced in the circuit by the horns as they move towards the opening position, the net interrupting capacity of the switch being a complex function variables. By providing a switch that has a high speed of contact separation preceded by a movement that inserted a large reactance in the circuit there is obtained a very efficient circuit interrupting action.

In compliance with the requirements of the patent statutes I have herein shown and described a preferred embodiment of my invention. It is however to be understood that the invention is not limited to the precise construction herein shown, the same being merely illustrative of the invention. WVhat I consider new and desire to secure by Letters Patent is:

An arcing horn comprising a ipe of iron of high reactance, the inside of said pipe being free of non-magnetic conducting material, whereby the magnetic material constitutes the solecurrent carrying portion of the horn, and a tip of copper at the end of the horn, said tip forming a continuation of the outer surface of the pipe, with the juncture of the tip and the pipe free of corners and abrupt changes in size.

2. An electric switch of the type including relatively movable cooperating main con tact members and relatively movable coopcrating arcing members shunting the main contact members and movable along one another during the switch opening operation to first substantially increase the length of arcing members in circuit and to then break the circuit between the arcing members, char acterized in that at least one of the arcing members comprises a cylinder of iron of high reactance, said cylinder comprising the sole current carrying part of said one arcing member intermediate the ends thereof, whereby the r-eactance of the circuit is increased as the arcing members slide along one another, and a tip of copper at the end of said one arcing member at the point of initial arc formation between the arcing members upon separation thereof, the surface of the tip being a con tinuation of the surface of said one arcing member, thereby definitely confining the arcing between the arcing members to said tip.

3. An electric switch of the type including relatively movable cooperating main contact members and relatively movable cooperating arcing members shunting the main contact members and movable along one another during the switch opening operation to first substantially increase the length of arcing members in circuit and to then break the circuit between the arcing members, characterized in that at least one of the arcing members comprises an outer cylinder of iron of high reactance, whereby the reactance of the circui is increased as the arcing members slide along one another, and av tip of copper at the end of said one arcing member at the point of initial arc formation between the arcing members upon separation thereof, the surface of the tip being a continuation of the surface of said one arcing member, thereby definitely confining the arcing between the arcing members to said tip.

ERNEST H. JACOBS.

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