US3143624A

US3143624A - Oil-poor switch with oil flow perpendicular to direction of movement of switch contact

Info

Publication number: US3143624A
Application number: US158222A
Authority: US
Inventors: Hofmann Werner
Original assignee: BBC Brown Boveri France SA
Current assignee: BBC Brown Boveri AG Germany; BBC Brown Boveri France SA
Priority date: 1960-12-13
Filing date: 1961-12-11
Publication date: 1964-08-04
Anticipated expiration: 1981-08-04
Also published as: DE1907463U; CH382259A; BE611365A; NL122542C; NL272410A

Description

4, 1964 w. HOFMANN 3,143,624

OIL-POOR SWITCH WITH on. FLOW PERPENDICULAR TO DIRECTION OF MOVEMENT OF SWITCH CONTACT Filed Dec. 11, 1961 2 Sheets-Sheet 1 ll 1-- a 1:: 3\ 5 I I3 3 v 4 q mama-.9?

INVENTOR Werner Ho-Fmann ATTORNEYS 4, 1964 w. HOFMANN 3,143,624

OIL-POOR SWITCH WITH OIL FLOW PERPENDICULAR T0 DIRECTION OF MOVEMENT OF SWITCH CONTACT Filed Dec. 11. 1961 2 Sheets-Sheet 2 INVENTOR Werner- Hofmmnn ATTORNEYS United States Patent OKs-POOR SWITCH WITH GIL FLOW PERPENDKI- ULAR T0 DIRECTION (IF MOVEMENT 0F SWITCH CONTACT Werner Hofrnann, Wettingen, Switzerland, assignor to Aktiengesellschaft Brown, Boveri 8: Cie, Baden, Switzerland, a joint-stock company Filed Dec. 11, 1961, Ser. No. 158,222 Claims priority, application Switzerland Dec. 13, 1960- 3 Ciaims. ((31. 200-150) This invention relates in general to electrical switches and more particularly to those switches of the so-called oilpoor type wherein oil is fed perpendicularly to the direction of movement of the movable contact part of the switch to facilitate extinction of the are drawn between the contacts as they are separated. Switches of this type include an extinguishing chamber for the arc, this chamber being subdivided into a plurality of part chambers and into which the oil is pressed in laterally. In these part chambers, the oil is vaporized by the corresponding electric arc. Then a high pressure is developed which expedites the arc extinction and again establishes a high value of voltage strength within the switching space to discourage re-ignition of the arc.

In the known constructions for this general type of switch, the oil is fed in from a single side and thereby the electric arc is pressed into the opposite side. The gases are then passed out of the chamber again on this side. The oil is here pressed out of the contact space, in which it was located just before the beginning of the switch-oil, into the individual parts of the extinguishing chamber, then vaporized in them and is then united again in an extingniishing medium collecting space. Movement of the oil is'caused by the movable contact part, in this case the contact pin itself.

In the known switch constructions, each part chamber leads across a common lead-off channel to the collecting space for the extinguishing medium, in which the gases can again unite. However, with this arrangement, there is the danger that through ionization of the gases outside of the point of contact, sparkovers can appear. This danger arises in that the outlet opening lying immediately one behind the other open into the collecting space for the extinguishing medium. Thus, gas parts get together again which are connected also in the extinguishing chamber and thereby tend especially to re-ignition.

In order to avoid these disadvantages and, in addition, obtain better utilization of the extinguishing chamber, the present invention provides an improved construction wherein the part chambers which collectively form the extinguishing chamber are connected with the space in which the switch contacts are located by means of oppositely disposed oil feed-in channels, and the collecting space is also connected with the part chambers by means of oppositely disposed oil lead-oft channels, these lead-in and lead-off channels being displaced relative to each other by approxi- 'mately 90, and the oppositely disposed lead-in and leadoff channels being arranged alternately on part chambers lying one behind the other.

Different embodiments of the improved construction in accordance with the invention are more particularly described hereinafter and illustrated in the attached drawings. In these drawings:

FIG. 1 is a view in central longitudinal section through the extinguishing chamber of the switch with the oppositely disposed lead-in channels being cut;

FIG. 2 is a view similar to FIG. 1 but with the oppositely disposed lead-oh channels being cut;

FIG. 3 is a transverse section taken on line 33 of FIG. 1;

FIG. 4 is a transverse section taken on line 4-4 of FIG. 2;

FIG. 5 is a transverse section taken on line 55 of FIG. 1;

FIG. 6 is a vertical central section of a modified construction wherein one of the discs forming part of the extinguishing chamber is made integral with the cover disc part thereof; and

FIGS. 7, 8 and 9 are detail views showing the construction of the various discs employed in the assembly of the extinguishing chamber.

With reference now to the drawings, the improved electrical switch is seen to be comprised of a hollow cylinder 3 the interior of which establishes a pressure generating chamber 3a in which the stationary tulip contact member lot the switch is arranged. The movable pin contact 2 which is adapted to engage with and be disengaged from the tulip contact 1 is shown in the switched-oh? position. The space within the hollow cylinder 3 is filled with oil which comes up to about the level indicated by the line 11. This oil is passed through oppositely disposed, 1ongitudinally extending lead-in channels 9, 9' into the extingushing chamber 12, through which passes the pin contact member 2, by way of superposed

transverse connecting channels

4, 5, 6 and 7. The

transverse channels

4 and 6 communicate with the right feed-in channel 9, and the

channels

5 and 7 communicate with the left feed-in channel 9'. The oil is thus alternately pressed out of channel 9 into channel 4, then out of channel 9' into channel 5, then again out of channel 9 into channel 6, and finally out of channel 9' into channel 7. An even larger number of superposed transverse channels can be provided if desired.

FIG. 2 illustrates the manner in which the vaporized oil is led ofli. From transverse channel 4, the oil vapor flows to the left into lead-01f channel 10'. From the transverse channel 5, the vapor flows to the right into lead-off channel 10. Similarly, oil vapor flows from transverse channel 6 into channel 10' and from transverse channel 7 into channel 10. Thus, here too the oil vapor passes alternately from transverse channels following one another into the lead-off channels 10, 10'. These latter lead into the collectingchamber 8 and it will be apparent that a re-ignition or spark-over is practically eliminated since the channels open on opposite sides of the arrangement.

The oppositely disposed feed-in channels 9 and 9' and the oppositely disposed lead-off channels 10 and 10' on the other side are displaced relative to each other by This is shown by a cross section through channel 4 as viewed in FIG. 3. Out of the feed-in channel 9 which now lies perpendicular to the plane of the drawing, the oil passes into the transverse channel 4, is there vaporized by the electric arc drawn between contacts 1 and 2, and then passes into the leadoff channel It). The transverse channel 6 is designed identically with transverse channel 4.

Transverse channels

5 and 7 are shifted by so that as to them a connection exists to the channels 9' and It across the transverse channels.

In order to separate the transverse channels 4-7 from each other, cover discs are provided as shown in FIG. 4. The transverse channels are also established in discs and hence, each channel is thus formed by a channel disc and a cover disc. The disc providing transverse channel 4 is denoted in FIG. 3 by 4' and similarly the discs correlated to the other transverse channels 57 are denoted in FIG. 1 by 5' to 7'. Dics 4' and 6 are identical and have the same orientation in the assembly. Disc 5' has the same structure as discs 4' and 6' but is displaced by an angle of 180 relative to the latter two discs in the assembly. Disc 7' as shown in FIG. 7 is similar to discs 4' to 6 but lacks any aperture that would register with the channel 9. The cover disc shown in FIG. 4 is designated 13. FIGS. 1 and 2 show three of these discs 13 at the upper part of the assembly. Discs 13' and 13 at the lower part of the assembly are detailed in FIGS. 8 and 9.

Thus, as seen in FIG. 3, each transverse channel disc, such as the disc 4 depicted in this view, includes an armate passageway extending for approximately 90 of arc and which includes a portion through which the movable contact 2 passes. The ends of the passageway terminate respectively in alignment with a lead-in channel, in this case channel 9, and a lead-off channel, in this case channel 10. Disc 4' also includes an aperture therethrough forming, in this case, part of the opposite lead-off channel 19 and another aperture therethrough forming, in this case, part of the opposite lead-in channel 9'. Disc 5' is arranged in the stack so that its arcuate passageway is displaced 180 from that of disc 4' so that the opposite ends thereof terminate in alignment respectively with leadin channel 9' and lead-off channel 10. The two other apertures therethrough would then form part of the opposite lead-off channel and lead-in channel 9.

Each cover disc 13 placed between the

discs

4 and 5, and between 5' and 6', includes a central aperture 12 forming part of the extinguishing chamber 12 through which the contact pin 2 passes, a pair of oppositely disposed apertures forming part of the feed-in channels 9, 9' and a. pair of oppositely disposed apertures forming part of the leadoff channels 10, 10'. Cover discs 13 shown in FIG. 8 is similar to disc 13 but omits any aperture corresponding to channel 9. Cover disc 13", shown in FIG. 9 has only the apertures corresponding to channels 10, 10' and aperture 12'.

The contact space, as shown in FIG. 5 is designed to have an oval configuration so that the lead-off channels lie in the walls of the contact chamber until they reach the oil collecting chamber 8.

In a modified construction as shown in FIG. 6, it is also possible to combine each transverse channel disc with a cover disc therefor into a single integrated structure rather than have two disc elements assembled in face-toof a stack of transverse channel discs alternating with cover discs, or a stack of discs incorporating both the transverse channel and its cover.

I claim:

1. In an oil-poor switch, the combination comprising a housing including an oil-filled pressure generating chamber containing a stationary contact member and a pin contact member movable in a vertically downward direction to disengage itself from said stationary contact member, said pin contact member being arranged to pass downwardly through an arc extinguishing device in said pressure generating chamber and which is constituted by a stack of superposed discs including a central opening extending longitudinally therethrough in alignment with said stationary contact member and through which said pin contact member passes, said stack of discs including also a pair of oppositely disposed longitudinally extending feed-in channels for the oil and a pair of oppositely disposed longitudinally extending lead-off channels for the oil, said feedin and lead-off channels being displaced relative to each other by 90, said feed-in and lead-oil? channels being alternately connected with each other by transversely extending channels in said discs intersecting said central opening such that the are drawn between said stationary and pin contact members is extended to the right and left in alternation in said transverse channels from said central opening, and an oil collection chamber located within said housing above said pressure generating chamber and which communicates with said lead-off channels.

face relation. Such an integrated structure would have a cross section as shown in FIG. 6.

The operation of the improved arc extinguisher arrangement is such that the electric arc will be extended to the left in the

transverse channels

4 and 6, and to the right in

transverse channels

5 and 7 as detailed in FIG. 2, the path of the are being shown by the zig-zag line 14. Thereby is achieved an extension 'on both sides. In addition, a complete separation of the rising gases has been made possible. The advantage of the arrangement is a better separation of the rising electric arc gases, better utilization on both sides of the extinguishing chamber, and a constructively simple production of the extinguishing chamber composed 2. An oil-poor switch as defined in claim 1 wherein said discs containing said transverse channels are separated from one another by discs which serve to cover said transverse channels, said cover discs being'provided with oppositely disposed apertures in alignment with and which form part of said oppositely disposed feed-in and lead-off channels, and a central aperture forming part of the open ing through which said pin contact member passes.

3. An oil-poor switch as defined in claim 1 wherein each said disc includes an integral cover element for its transverse channel.

References Cited in the file of this patent UNITED STATES PATENTS 2,067,648 Reher Jan. 12, 1937 2,412,857 Baker Dec. 17, 1946 2,762,890 Taylor et al Sept. 11, 1956 2,909,633 Umphrey Oct, 20, 1959 FOREIGN PATENTS 94,950 Norway Sept. 12, 1959

Claims

1. IN AN OIL-POOR SWITCH, THE COMBINATION COMPRISING A HOUSING INCLUDING AN OIL-FILLED PRESSURE GENERATING CHAMBER CONTAINING A STATIONARY CONTACT MEMBER AND A PIN CONTACT MEMBER MOVABLE IN A VERTICALLY DOWNWARD DIRECTION TO DISENGAGE ITSELF FROM SAID STATIONARY CONTACT MEMBER, SAID PIN CONTACT MEMBER BEING ARRANGED TO PASS DOWNWARDLY THROUGH AN ARC EXTINGUISHING DEVICE IN SAID PRESSURE GENERATING CHAMBER AND WHICH IS CONSTITUTED BY A STACK OF SUPERPOSED DISCS INCLUDING A CENTRAL OPENING EXTENDING LONGITUDINALLY THERETHROUGH IN ALIGNMENT WITH SAID STATIONARY CONTACT MEMBER AND THROUGH WHICH SAID PIN CONTACT MEMBER PASSES, SAID STACK OF DISCS INCLUDING ALSO A PAIR OF OPPOSITELY DISPOSED LONGITUDINALLY EXTENDING FEED-IN CHANNELS FOR THE OIL AND A PAIR OF OPPOSITELY DISPOSED LONGITUDINALLY EXTENDING LEAD-OFF CHANNELS FOR THE OIL, SAID FEEDIN AND LEAD-OFF CHANNELS BEING DISPLACED RELATIVE TO EACH OTHER BY 90*, SAID FEED-IN AND LEAD-OFF CHANNELS BEING ALTERNATELY CONNECTED WITH EACH OTHER BY TRANSVERSELY EXTENDING CHANNELS IN SAID DISCS INTERSECTING SAID CENTRAL OPENING SUCH THAT THE ARC DRAWN BETWEEN SAID STATIONARY AND PIN CONTACT MEMBERS IS EXTENDED TO THE RIGHT AND LEFT IN ALTERNATION IN SAID TRANSVERSE CHANNELS FROM SAID CENTRAL OPENING, AND AN OIL COLLECTION CHAMBER LOCATED WITHIN SAID HOUSING ABOVE SAID PRESSURE GENERATING CHAMBER AND WHICH COMMUNICATES WITH SAID LEAD-OFF CHANNELS.