US1934630A - Circuit breaker - Google Patents

Description

s. RUMP CIRCUIT BREAKER Nov. 7, 1933- Filed March 8, 1930 gurd Rump Patented Nov. 7, 1933 UNITED STATES PATENT OFFICE CIRCUIT BREAKER.

' land Application March 8, 1930, Serial No. 434,259, and

in Germany March 9, 1929 5 Claims.

This invention relates to improvements in electric circuit controlling means. and more particularly to oil switches having means associated therewith for assisting in quenching the arc oc curring thereinwhen such switch is opened.

- It is very necessary to'provide for a rapid cooling of the are occurring upon separation of the contacts in an oil switch in order that the most favorable disconnecting action may take place. If the switch contacts are arranged in an oilfilled chamber, the gases rising into the upper portion of the chamber create a certain pressure above the oil level in the switch tank or container. These gases cause a flow of oil through an aperture through the quenching chamber around the movable contact, which flow may even amount to an ejecting action. If the flow of oil is suiii ciently rapid, the movement of the oil will cause a rapid cooling of the arc and thereby aid in quenching the same.

a The oil current must, however, flow through the aperture provided for movement of the movable contacts, and it is possible that the movable contact may so far block the aperture that the oil current will actually take place only after the movable contact has been withdrawn the full range of its movement so that a sufiicient cooling, because of an insuihcient flow of oil, does not take place. It is necessary, therefore, that at least a portion of the'oil flow from the quenching chamber take place substantially as soon as the contact has been broken.

It is also important that the oil current from the quenching chamber continue for a sufficient length of time to provide for proper cooling of the are. For this reason, the gases formed upon opening of the switch must have a certain pressure with respect to a certain volume of the oil. When the contacts are first opened, it is necessary, in order that the gases may form, that a small quantity of oil be immediately forced out of the chamber. 1

In previously devised arrangements employing quenching chambers, the only passageway or aperture provided in the quenchingchamber for the ejection of the oil was immediately about the movable contact so that the oil was forced out through the space remaining in the aperture about the movable contacts without, in any way, coming into contact with the arc, thereby losing any cooling effect that such oil current might produce.

It is, therefore, among the objects of the present invention, to providean oil switch of the arc-quenching chamber type wherein, upon the separation of the switch contacts, oil is forced out of the quenching chamber to permit the pressure, created as result of the formation of the arc, to be reduced to an extent such as will permit the formation and expansion of gases to cause the expulsion of additional oil from the chamber in such a manner as to quench the arc.

Another object of the invention is to provide an oil switch in which the movable contacts are so formed that the oil current is forced to flow irectly about the tip of the contacts in such manner that the oil current is brought directly into contact with the are between the movable contacts andthe fixed contacts of the switch structure.

Another object of the present invention is to provide an oil switch structure in which the contacts and the quenching chamber are so formed that, upon opening action causing formation of an arc and the production of gases, the oil within the quenching chamber is first forced away from the lower portion of the chamber and then, toward the end of the opening movement, fiows through the end of the movable contacts directly in contact with the arc.

Objects and advantages, other than those above set forth, will be apparent from the following description andthe drawing in which;

Figure 1 is a vertical cross-sectional view of an oil switch illustrating an embodiment of the present invention; r

Fig. 2 is a top plan view, taken substantially on the line A--A of Fig. 1, showing a unitary construction of the oil quenching chambers;

Fig, 3 is a top plan view, similar to that shown in Fig. 2, in which the quenching chamber is formed as a complete unit on one side of the contact operating means;

Fig. 4 is a detailed View showing one embodiment of the arrangement and structure of the movable contacts and the oil-quenching chamber therefor; and

Fig. 5 is a modified form of an embodiment similar to that shown in Fig. 4;

Referring more particularly to the drawing by characters of reference, reference numeral 6 indicates a switch container having a cover plate (not shown) through which bushings '7 are arranged to extend for the purpose of providing a means for protecting and insulating a plurality of electrical conductors terminating in a plurality of fixed or stationary contacts 8. A' plurality of movable contacts 9 are arranged to be brought into bridging engagement with the fixed contacts 8 up n movement of a contact operating mechanism 11 which is operable by the usual means for such switches, such structure being therefore not shown or described herein.

Both sets of contacts, that is, the fixed contacts 8 and the movable contacts 9, are substantially enclosed within arc-quenching chambers 12 when the contacts are in the normally closed or connecting position, as shown in Fig. l. The quenching chambers 12 are provided, through the bottom portion thereof, with apertures 13 through which the movable contacts 9 are arranged to move for the connecting or disconnecting action.

When the contacts are separated and an arc occurs between the fixed and movable contact end portions, the occurrence of such are creates gases within the oil filling the quenching chambers, as shown in Figs. 4 and 5, and the gases expand to force a portion of the oil out of the aperture 13 around the movable contact 9. The movable contacts 9 are preferably made hollow and are provided with a piston-like enlarged end 14 in order that a portion of the oil in the quenching chambers 12 may first be forced out through the apertures 13 without permitting the gas to flow directly through the contacts.

The gases collecting in the upper portion of the quenching chambers, upon the occurrence of a disconnecting action, press the oil downwardly through the apertures 13 until the movable con tact 9 with its piston-like end 14 closes the apertures. Toward the end of the disconnecting action 4, the oil then can flow only into the tubular end of the contacts and must flow out of the quenching chamber through the contacts so that the arc is quenched by the intensive cooling of the oil current flowing through the contacts.

If desired, the movable contacts may likewise be made without the piston-like enlarged end in which event it is necessary to provide a plurality of apertures 15 in order that the oil may flow out through such apertures in addition to flowing out through the space within the quenching chamber aperture about the movable contacts.

In some cases it may be found desirable to enclose each set of contacts, that is, a fixed contact 8 and a movable contact 9 within a separate quenching chamber 12 as shown in Fig. 2. In other cases, however, it may be found desirable to combine all of the quenching chambers on one side of the switch operating mechanism 11 into a single unit in order that the gases occurring upon disconnecting action of the switch may cooperate throughout the quenching chamber and cause a simultaneous quenching of the are on each side of the contact operating mechanism.

It will thus be seen that a structure has been provided in which, during the first part of the disconnecting action of an oil switch, the gas pressure produced in the quenching chamber forces the oil out of the lower portion of the quenching chamber without coming into direct contact with the arc. An oil current is, therefore, established so that, when the movable contact closes the aperture in its downward movement, the oil current so established must flow out through the tubular movable contacts, thereby coming directly into contact with all portions of the are at its attachment on the end of the mov able contacts and providing for such intensive cooling of the are as to aid in quenching the same very quickly.

Although but a few embodiments of the present invention have been illustrated and described, it will be apparent that various modifications may be made therein without departing from the spirit of the invention or from the scope of the appended claims.

The invention claimed is:

1. In an electric switch, a chamber containing an arc quenching fiuid and having an aperture therethrough, a fixed contact supported within said chamber, a cooperating tubular contact extending through said aperture and having an enlarged portion movable to and from connection with said fixed contact, the said aperture and said tubular contact constituting parallel passages for the expulsion of said fluid from said chamber upon the generation of gases therein responsive to the creation of an arc incidental to the initiation of movement of said tubular contact from connection with said fixed contact, and the said enlarged portion constituting a valve member operable, during continuation of movement of said tubular contact from said fixed contact, to close said aperture against the flow of said fiuid therethrough to thereby cause said fluid to flow from said chamber by way of said tubular contact only whereby the rate of flow of said fluid therethrough is increased.

2. In an electric switch, a chamber containing an arc quenching fluid, a fixed contact supported within said chamber, a cooperating tubular contact extending through said chamber movable to and from connection with said fixed contact, a a plurality of apertures constituting passages for the flow of said fluid from said chamber, the said tubular contact constituting one of said passages and being operable, during movement thereof from connection with said fixed contact, to prevent the fiow of said fluid from said chamber by way of another of said passages.

3. In an electric switch, a chamber containing an arc quenching fluid, a fixed contact supported within said chamber, a cooperating contact extending through said chamber movable to and from connection with said fixed contact, the said cooperating contact being provided with a pluraiity of apertures constituting passages for the expulsion of said fluid from said chamber upon the occurrence of the generation of gases within said chamber responsive to the creation of an arc incidental to the initiation of movement of said cooperating contact from connection with said fixed contact, the said contact being operable, during continuation of movement thereof from connection with said fixed contact, to limit flow of said fluid from said chamber to one only of said apertures to thereby accelerate the rate of movement of said fluid through the said one only of said apertures.

4. In an electric switch, a chamber containing an arc quenching fluid and having a plurality of apertures extending therethrough, a plurality of fixed contacts supported within said chamber, and a cooperating tubular contact for each of said fixed contacts, each of said tubular contacts extending through a separate one of said apertures and having an enlarged portion mov able to and from connection with the associated one of said fixed contacts, the said apertures and said tubular contacts constituting parallel passages for the expulsion of said fluid from said chamber upon the generation of gases therein responsive to the creation of arcs incidental to the initiation of movement of said tubular contacts from connection with said fixed contacts, and the said enlarged portions constituting a plurality of valve members operable, during continua tion of movement of said tubular contacts from said fixed contacts, to close said apertures against 1 0 flow of said fluid therethrough to thereby cause said fluid to flow from said chamber by way of said tubular contacts only whereby the rate of flow of said fluid therethrough :is increased and quenchment of said arcs accelerated.

5. In an electric switch, a chamber containing an arc quenching fluid and a plurality of apertures extending therethrough, a plurality of fixed contacts supported within said chamber, a cooperating tubular contact for each of said fixed contacts, each of said tubular contacts extending through a separate one of said apertures and having an enlarged portion, means operable to simultaneously move said tubular contacts to and from connection with their associated fixed contacts, the said apertures and tubular contacts constituting parallel passages for the expulsion of said fluid from said chamber upon generation of gases therein responsive to the creation of arcs incidental to the initiation of movement of said tubular contacts from connection with said fixed contacts, and the said enlarged portions constituting valve members operable, during continuation of movement thereof, from connection with said fixed contacts, to close said apertures against flow of said fluid therethrough to thereby permit the flow of said fluid from said chamber by way of said tubular contacts only whereby the rate of flow of said fluid therethrough is increased and quenchment of the arcs accelerated.

SIGURD RUNIP.

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