US2032241A - Contacts for electric circuit breakers, switches, connecters and the like - Google Patents

Description

Patented Feb. 25, 1936 UNITED STATES PATENT OFFICE George Ethelbert Whitehead, Rhiwbina, near Cardiff, South Wales Application December 19, 1933, Serial No. 703,108 In Great Britain January 6, 1933 6 Claims.

This invention relates to plug and socket type contacts of electrical circuit breakers, switches, connecters and the like and for its main object aims to provide an improved form of socket con- 5 tact and for another object, seeks to produce improved forms of the main and auxiliary contacts `claimed in my earlier application Serial No. 632,073. f

To enable the invention to be clearly understood, it will now be described with reference to the accompanying drawing in Which Fig. l is a sectional elevation of the socket contact in accordance with the invention and; Fig, 2 is an enenlarged plan View of part of the socket contact shown in Fig. 1, whilst Fig. 3 is asectional elevation of the contacts of the circuit breaker as claimed in my earlier application Serial No. 632,073 aforesaid, with the present invention applied to both the main current carrying contact members.

According to the present invention, a socket contact member has its female contact surface formed by the inner edges of a plurality of circularly stacked lamin retained in a carrier in such manner that said surface is resiliently expansible. Conveniently, said contact comprises a large number of similar bent strips, preferably of copper, stacked so that at their outer ends .,O they bear against an outer ring or housing so as to be self-retaining in the radial direction, means being provided to retain the strips against longitudinal displacement only. If desired, each two adjacent lamina may have between them a phos- 35 phor bronze or steel backing spring bent to the same shape but preferably of slightly less length than the copper strips.

According to a further feature of the invention, the main current carrying contacts of 40 switches or circuit breakers as claimed in the aforesaid application are constituted respectively by an enlarged portion of the plug contact and by an annularly laminated contact as hereinbefore set forth, housed in an enlarged down- 45 wardly extended mouth ring of the arcing chamber or housing of the arcing contacts. Preferably, the enlarged portion of the plug contact has longitudinal bores to permit oil or other fluid to flow freely at all times into the arcing chamber 50 or housing. Preferably also the main current carrying contacts are arranged to separate before the arcing contacts separate.

Referring rst to Figs. 1 and 2 of the drawing, the socket contact comprises the ring or housing 55 |0| having a stem portion |02 for connection to (Cl. 20D-166) any current conductor as desired. The housing is provided with an inner shoulder |03 between which and a retaining ring |04 are held the circularly stacked lamin |05. The end of the plug contact is indicated at |06. 5

The lamin are preferably all bent to the same shape shown on an enlarged scale in Fig. 2 so that the outer edges bear against the inner cylindrical wall of the housing |0| at an angle to the radii whilst the inner ends are substantially radial as shown at |01. If desired, such as in large contacts, each lamina |05 may be separated from the next by a phosphor bronze or even steel lamina |08 which has the same general shape but is of slightly shorter length than are the lamina: |05 which are preferably of copper.

Referring next to Fig. 3, the latter is similar to Fig. 2 of my aforesaid earlier application.

It will be seen from Fig. 3 that the arcing chamber or housing 2| has a downwardly extend- 20 ing mouth ring portion |0|' of larger diameter than is shown in the aforesaid earlier application, this portion having a retaining ring |04' and constituting the housing as shown in Figs. 1 25 and 2 of the drawing herewith for the laminated annular main current carrying contact |05 with which co-operates a portion |09 of larger diameter than the moving contact, the end 5 of which latter co-operates with the housed contacts 3. The arcing plug 5 may be screwed into a bore I0 in the enlarged plug portion |09 and the latter is preferably provided with a plurality, for example four, of longitudinal bores through which oil can pass at all times, as indicated by the chain line arrow, into the housing 2| and out through the gas escape openings 22 therein.

In Fig. 3 the moving Contact member is shown in the closed position in full lines whilst in dotted lines it is shown in the position which it occupies at the instant of commencement of arcing and it will be seen that at this instant there is a relatively large annular opening through which oil can flow around the plug member |09 as indi- 45 cated by the two full line arrows.

It will be understood that various minor modications may be made within the scope of the invention.

I claim:

1. An electrical socket contact member, comprising an annular housing and held therein an annulus of closely packed thin flexible lamin each of which is engageable with the one on each side of it along a plurality of longitudinal lines of contact of which at least one line is adjacent the inner edge of the lamina thereby providing a substantially solid Wall adjacent to said inner edge and forming a socket member with an effectively continuous resiliently expansible laminated brush form of female contact surface.

2. An electrical socket contact member, comprising an annular housing and held therein an annulus of closely packed thin flexible lamin each of which is engageable with the one on each side of it along a pluralityrof longitudinal lines of contact of which at least one line is adjacent the inner edge of the lamina thereby providing a substantially solid Wall adjacent to said inner edge and forming a socket member with an effectively continuous resiliently expansible laminated brush form of female contact surface, alternate lamina: being of stiier material and of only slightly shorter radial length than the other lamin.

3. An electrical socket contact member, comprising an annular housing and held therein an annulus of closely packed thin iiexible lamin each of which is engageable with the one on each side of it along a plurality of longitudinal lines of contact of which at least one line is adjacent the inner edge of the lamina thereby providing a substantially solid wall adjacent to said inner edge and forming a socket member with an eiectively continuous resiliently expansible laminated brush form of female contact surface, all said lamin having a similar general curvature as distinct from angularity.

4. An electrical socket contact member, comprising an annular housing and held therein an annulus of closely packed thin exible lamin each of which is engageable With the one on each side of it along a plurality of longitudinal lines of contact of which at least one line is adjacent the inner edge of the lamina thereby providing a substantially solid Wall adjacent to said inner edge and forming a socket member With an eiectively continuous resiliently expansible laminated brush form of female contact surface, all said lamina: Yhaving a similar general curvature as distinct from angularity and alternate laminas being of stiier material and of only slightly shorter radial in the opposite direction at the ends, each of which lamin is engageable with the one on each side of it along a plurality of longitudinal lines of contact of which at least one line is adjacent the inner edge of the lamina thereby providing a sub- V-stantially solid Wall adjacent to said inner edge and forming a socket member With an effectively continuous resiliently expansible laminated brush form of female contact surface.

6. An electrical circuit breaker having a tubular metal housing, a pair of relatively longitudinally movable cooperating contacts of Which one is of elongated plug form whilst the other contact is located in said tubular metal housing with its contact surface disposed between the ends of said housing and protruding inwardly from the inner Wall surface thereof, a mouth ring forming part of said housing and through which said elongated plug contact enters to engage only said contact within said housing, said housing comparatively closely surrounding the engaging contact and being provided with an opening for the free escape of the arc gases, an enlarged extension of said mouth ring, an enlargement on said plug contact, and an annulus of closely packed thin flexible lamin held in the mouth ring each of which lamn is engageable With the one on each side of it along a plurality of longitudinal lines of contact of which at least one line is adjacent the inner edge of the lamin thereby providing a substantially solid Wall adjacent to said inner edge and forming a socket member with an effectively continuous resiliently expansible laminated brush form of female contact surface which is adapted to be engaged by the enlargement on said plug contact, said enlargement constituting the main current carrying plug member.

GEORGE ETHELBERT WHITEHEAD.

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