US2116383A - Liquid contact circuit closer - Google Patents

Description

May 3, 1938. e. cARLsoN LIQUID CONTACT CIRCUIT CLOSER Filed March 11, 1957 Irwvemtori:

Ge oTgeK/Car 5 oh b 79 M7 MZW y His Attorney Patented May 3, 1938 PATENT OFFICE LIQUID CDNTACT CIRCUIT CLOSER George Carlson, Bridgeport, Conn., assignor to General Electric Company, a corporation of New York Application March 11,

5 Claims.

In the accompanying drawing, Fig. 1 is a side elevation, partly broken away, of a liquid contact circuit closer embodying my invention, the circuit closer being in thecircuit interrupting position. Figure 2 is a similar view of the circuit closer, it being in the circuit closing position, and Fig. 3 is a sectional view taken on line 3-3 of Fig. 1.

Referring to the drawing, I have illustrated my invention applied to a liquid contact circuit closer having a pair of cup-shaped metal terminals I which are separated by a diaphragm comprising abutting plates 2 and 3 of a refractory material, such as a ceramic. The outer edges of the plates 2 and 3 are provided with shoulders 4 for receiving the flanges 5 of the terminals. The flanges 5 are sealed by a head 6 of glass which also seals the junctions between the flanges Sand the plates 2 and 3 and the junction between the plates 2 and 3. Within the space enclosed by the terminals is a suitable quantity of mercury I which forms the conducting medium between terminals. In the manufacture of the circuit closer the space enclosed by the terminals is evacuated and filled with hydrogen at a pressure of one or more atmospheres which increases the current interrupting capacity of the circuit closer. The diaphragm is provided with a passage formed by openings 8 and 9 in the plates 2 and 3. As shown in Figs. 1 and 2 this passage is submerged in the mercury when the circuit closer is in the current conducting position and is raised out of the mercury when the circuit closer is in the circuit interrupting position. The passage formed by the openings. Band 9 is arranged so that as the circuit closer is moved from the circuit closing to the circuit interrupting position mercury flows simultaneously from each end of the passage. In the abutting faces of the plates 2 and 3 are recesses forming a depression III in thepassage .formed by the openings 8 and 9. This depression is arranged so that as the circuit closer is moved to the circuit interrupting position a portion ll of the mercury is retained in the depression. As the circuit closer is moved to the cir- 1937, Serial No. 130,261

cuit interrupting position the circuit between the terminals is broken between the retained portion II of the mercury and the mercury flowing from each of the openings 8 and 9. This provides a double break which increases the interrupting capacity of the circuit closer. When the circuit closer is returned to the position shown in Fig. 2, the mercury flows into each of the openings 8 and 9 and joins with the pool II to complete the circuit between the terminals. Due to the surface tension of the mercury, there is an are between the particles of mercury during joining which is of longer duration than the arc during the separation of the mercury to interrupt the circuit. The are during joining of the mercury is also decreased by the presence of the pool lI'. Another advantage resulting from the presence of the pool I I is a decrease in wear due to erosion of "the ceramic in the passage defined by the openings 8 and 9. This wear is due'to seepage of particles of mercury into the interstices of the ceramic and to subsequent arcing of these particles which causes the particles of mercury to be forced out of the interstices with an explosive efiect. Since ceramics are all porous, this type of wear is always present when thediaphragm is a ceramic. The present construction decreases this type of wear since the arcing tends to be confined to the edges of the pool II.

It will be noted that the shape-of the depression III is such that it holds an increasing amount of mercury as the circuit closer is'moved to the interrupting position. As the circuit closer is moved to the circuit interrupting position there is therefore a flow of mercury into the depression III which aids the separation of the mercury. During movement of the circuit closer to the circuit closing position, there is a flow of mercury from the depression III which aids the joining of .the mercury.

In the use of the circuit closer the circuit closer is rotatably supported for rotation about the axis of its terminals in such a manner that the passage defined by the openings 8 and 9 is horizontal. By rotation of the circuit closer through a small angle the circuit closer may be moved to the circuit closing and circuit interrupting positions shown in Figs. 1 and 2. As the circuit closer is moved from the circuit closing position to the circuit interrupting position the circuit between the terminals is interrupted between the mercury fiowing from each end of the passage defined by openings 8 and 9 and theportion II of the mercury retained in the depression III. The circuit interruption, therefore, takes place entirely in the mercury and since it is interrupted in a plurality of places the circuit interrupting capacity of the switch is increased.

I have shown the diaphragm between the terminals from two abutting plates of insulating material. It is obvious that a greater number of plates could be used and that by providing a mercury retaining depression between each pair of plates the interrupting capacity of the circuit closer could be further increased.

'What I claim as new and desire to secure by Letters Patent of the United States, is:

1. In a liquid contact circuit closer, an envelope having an electrically conducting liquid therein, a diaphragm separating the liquid into two pools, a terminal contacting the liquid on each side of the diaphragm, a passage through the diaphragm for connecting said pools to complete a circuit between the terminals, said passage being arranged so that the liquid flows simultaneously from each end thereof as the circuit closer is moved to a circuit interrupting position in which the passage is raised above the liquid level in the envelope, and a depression in said passage between its ends for retaining a portion of the liquid as the circuit closer is moved to the circuit interrupting position whereby the circuit is broken from each side of the retained liquid, said depression being constructed so that the liquid retained therein is raised above the liquid level in the envelope as the passage is raised above the liquid level.

2. In a liquid contact circuit closer, an -envelope for an electrically conducting liquid comprising a pair of opposed cup-shaped metal terminals, a diaphragm between the adjacent edges of said terminals, said diaphragm comprising a plurality of abutting plates, a bead of sealing material joining said terminals and sealing the junction between said plates, openings in said plates providing a. passage through the diaphragm for completing a circuit between the terminals, said passage being arranged so that the liquid flows simultaneously from each end thereof as the circuit closer is moved to a circuit interrupting position in which the passage is raised above the liquid level in the envelope, and a recess in the abutting face of one of said plates providing a depression in said passage between its ends for retaining a portion of the liquid as the circuit closer is moved to the circuit interrupting position .whereby the circuit is broken from each side of theretained liquid, said depres= sion being constructed so that the liquid retained therein is raised above the liquid level in the envelope as the passage is raised above the liquid level.

3. In' a liquid contact circuit closer, an envelope having an electrically conducting liquid therein, a diaphragm separating the liquid into two pools, said diaphragm comprising a plurality oi. abutting plates, a terminal contacting the liquid on each side of the diaphragm, openings in said plates providing a passage through the diaphragm for connecting said pools to complete a circuit between the terminals, said passage being arranged so that the liquid flows simultaneously from each end thereof as the circuit closer is moved to a circuit interrupting position in which the passage is raised above the liquid level in the envelope, and a recess in the abutting face of 'one of said plates providing a depression in said passage between its ends for retaining a portion of the liquid as the circuit closer is moved to the circuit interrupting position whereby the circuit is broken from each side of the retained liquid, said depression being constructed so that the liquid retained therein is raised above the liquid level in .the envelope as the passage is raised above the liquid level.

having an electrically conducting liquid therein,

a diaphragm separating the liquid into two pools,

a terminal contacting the liquid on each side of the diaphragm, a passage through the diaphragm for connecting said tools to complete a circuit between the terminals, said passage being arranged so that the liquid flows simultaneously from each end thereof as the circuit closer is moved to a circuit interrupting. position, and a depression in said passage between its ends for retaining a portion of the liquid as the circuit closer is moved to the circuit interrupting position whereby the circuit is broken from each side of the retained liquid, said depression being shaped so that the volume of liquid held therein increases as the circuit closer is moved from the circuit closing to the circuit interrupting position.

5. Ina liquid contact circuit closer, an envelope having a quantity of mercury therein, a barrier separating the mercury into two pools, a terminal contacting the mercury on each side of the barrier, a passage over the barrier for connecting said pools to complete a circuit between the terminals, said passage being arranged so that the mercury flows simultaneously from each end thereof as the circuit closer is moved to a circuit interrupting position in which the passage is raised above the liquid level in the envelope, said passage having a ceramic surface over which the mercury flows, and a depression in said passage between its ends for retaining a portion of the mercury as the circuit closer is moved to the circuit interrupting position whereby the circuit is broken from each side of the retained mercury, said depression being constructed so that the liquid retained therein is raised above the liquid level in the envelope as the passage is raised above the liquid level.

GEORGE CARLSON.

e RT FIcA'TE 0F CORRECTION. I

Patent No. 2,116,585. may 5; 959

- GEORGE cABLsoN.

It is hereby certified that error appears gin theprint ed specification of the above numbered patent requiringeor renation as follows: Page 2, second column, line 26, claim 1 for the word "tools" read pools; andthat the said Letters Patent. should be read with thie correction therein that the same may conform to the record of, the case in Nae Patent Office.

Signed. and sealed thie'lhth day of J1me, A., D. 19 8'.

Henry Van Arsda-le (Seal? :Acting cennnissioner of Patents.

Images