US1653086A

US1653086A - Electric switch

Info

Publication number: US1653086A
Application number: US624835A
Authority: US
Inventors: Christensen Christen; Philip G Langley
Original assignee: General Electric Co
Current assignee: General Electric Co
Priority date: 1923-03-13
Filing date: 1923-03-13
Publication date: 1927-12-20
Anticipated expiration: 1944-12-20
Also published as: GB217013A; FR578243A

Description

Dec. 20, 1927.

C. CHRISTENSEN ET AL ELECTRIC SWITCH Filed March 13., 1925 aww fuw rs e on n .Len r 0 e t FM m n .m I H p i h v T w h C /////lllllll Patented Dec. 20, 1927.

,RATIIGN OF 'NEW YORK.

insane ts'WITCI-li.

Application filed Ii larch i3, 19%.

Our invention relates to electric switches of the oil break type such as are used to control high potential circuits and which comprise a set of main switch contacts for normally carrying the load current and set of auxiliary explosion chamber contacts for making the final break of the circuit.

One object of our invention is to provide an arrangement in which an impedance is included in the connection between the mainv and its auxiliary star 1: contacts.

Another objectis to provide for supporting the two sets of com-acts in the same oil tank in a manner to facilitate the introduc tion of the desired impedance between the aforesaid contacts.

A further object is to provide arrangement of main and auxiliary switch contacts whereby the gas produced by the one set of contacts shall not interfere with the proper functioning of the other set.

Our invention will be better understood by reference to the accompanying specification and drawing and its scope will be pointed out in the appended claims.

Figure l is a view illustrating our invention, partsv being broken away to more clearly show the construction.

Fig. 2 is a transverse sectional view of the same taken on the line 2-2 of Fig. 1.

Referring now to the drawing, an oil pot 1 having an insulating lining 2 and containing a quantity of oil 3 has a cover a carrying all of the switch terminals which are removable therewith. Two insulator bushings 5, 5 carry conductors 6, 6 and are mounted in diametrically opposite openings in the cover, suitable clamping rings 7 being provided to secure them in a vertical position. Each conductor 6 connects with a terminal 8 having a main contact 9 and an arcing contact 10. The movable member of the switchcomprises a bridging member having a pair of arms 11 extending in opposite directions from the center operating rod 12 and a second pair of arms 13 also extending in opposite directions from the operating rod 12 but atright angles to the arms 11. At the extremities of the arms 11 suitable contact plates i l and 15 are provided for engagement with the main and arcing contacts 9 and 10 respectively. The parts thus described constitute what may be termed the main switch and may be designed to provide whatever current carrying capacity is deeded;

in orde" that the switch may be employed to interri i iigi tension ch-cuiis particu larly under circuit conditions without the oil throwing disadvantage connnon to such switches we have provided an auxiliary s 'tch of the e' 'plosion chamber type, which switch is connected. in parallel relation to the main switch, the construction being such that the a. switch is opened subse quently to inain switch. At diametri" cally opposi..= points and equally distant from the

insulator bushings

5, 5, a pair of small insulators l6 and 17 are secured to the under side of the cover l by clamps 18. Each of these insulators, one of which is shown in partial section in Fig. 1 carries an inverted cup 19 having a cover 90 and forming an explosion chamber 21. A stationary contact 22 in this chamber is sup ported by a tube threaded into the base of the-inverted cup 1.9, the contact 22 being adapted to receive the rod constituting the mo *ablecontact of this switch. The rous 2 1 are carried by the arms 13 and are of such length that the circuit between them and the stationary contacts is not broken until after the circuit is broken at its main switch. For placing the auxiliary switch in parallel relation to the main switch each stationary contact 22 is electrically connect ed with one of the terminals 8 of the main switch. This connection comprises

straps

25 and 26 which are preferably of resistance material. However, under certain circumstances it may be found desirable to employ a reactance instead of a resistance or even a pair of conducting bars of negligible resistance. The arrangement of the stationary switch terminals at the four corners of an imaginary square has, aside from struc tural advantages, the advantage that the main and auxiliary switch contacts are separated laterally a considerable distance which enables the contacts of the main switch to open without the possible interference of the gas therefrom with the auxiliary switch and permitting the latter switch to utilize fresh quantities of oil. This arrangement is also especially adapted for the conductive connection between the main and the auxiliary switch terminals.

In the operation of the switch, assuming the parts to be in closed circuit position, the initial downward movement of the operating rod 12 carries with it the bridging member and the arms 11 thereof first break contact with the terminals 8 of the main switch. There still remains a circuit connection be tween the terminals 8 through the auxiliary switch and the straps and 26. Upon further downward movement oi the operating rod, the movable contact rods 24 of the auxiliary switch break the remaining shunt cir cuit in the explosion chambers 21.

It is well known that the presence of inductive loads makes it more difficult to break the circuit thereof. Since the tangent of the angle of lag is an inverse function of the resistance in the circuit it w ill be obvious that the additional resistance of the

straps

25 and 26 when directly included in the circuit will exercise a beneficial eiiect upon the circuit by improving the power factor, there by facilitating the final breaking of the circuit by the auxiliary switch,

lVhile we have described only one embodiment of our invention, we do not wish to be limited to the particular form shown and described as it will be apparent that many modifications therein may be made without departing from the scope of our invention as set forth in the appended claims.

hat we claim as new and desire to secure by Letters Patent of the United Si ates, is:

1. An electric switch comprising a rccep tacle having a cover and :ulapted to contain an insulating liquid, insulator bushings mounted in the cover, fixed contacts carried thereby, insulators depending from the cover and spaced laterally on opposite sides of .a line joining said insulator bushings,

an explosion chamber containing a fixed auxiliary contact supported by each insulator, impedance connecting each fixed main contact with a separate fixed auxiliary contact, a movable bridging member having main contacts for engaging the fixed main contacts and having laterally extending arms carrying movable auxiliary contacts, said latter contacts being arranged to disengage the fixed auxiliary contacts in the explosion chambers subsequently to the disengagement of the main contacts and said impedances being arranged in the receptacle beneath the liquid level.

2. An electric switch comprising a receptacle having a cover and adapted to contain an insulating liquid, insulator bushings mounted in the cover, fixed contacts carried thereby, insulators depending from the cover and spaced laterally on opposite sides of a line joining said bushings and at equal distances from the bushings, an explosion chamber contaii'iing a fixed auxiliary contact supported by each insulator, an impedance connecting each fixed main contact with a separate fixed auxiliary contact, a movable bride-ingmember having main contacts for 'ing the fixed contacts and having arms sliding laterally from opposite side thereot carrying movable auxiliary contacts, said latter contacts being arranged to disengage the fixed auxiliary contacts in the explosion chamber subsequently to thedisengagement of the main contacts.

In Witness whereof, CHRISTEN Crnnsrnm sm: has hereunto set his hand this 2nd day of March, 1923, and PHILIP G. LANGLEY has hereunto set his hand this 8th day of March,

CHRISTEN CHRISTENSEN. PHILIP G. LANGLEY.

v Certificate of Correction. Patent No. 1,653,086. Granted December 20, 1927, to CHRISTEN CHRISTENSEN ET AL.

It is hereby certified that error appears in the printed specification of the abovenumbered patent requiring correction as follows: Page 2, line 70, claim 2, for the Word side read sides; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent ()flice.

Signed and sealed this 17th day of January, A. D. 1928.

[SEAL] M: J. lVIJORE Acting gommissioner of Patents.

Certificate of Correction Patent No. 1,653,086. Granted December 20, L927, to CHRISTEN CHRISTENSEN ET AL.

It is hereby certified that error appears in the printed specification of the abovenumbered patent requiring correction as follows: Page 2, line 70, claim 2, for the Word side read sides; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Oflice.

Signed and sealed this 17th day of January, A D. 1928.

[SEAL] M; J. MOORE,

. Acting Commissioner of Patents.