Cooled contact rectifier

Nov. 7, 1939. c. c. HEIN 2,179,293

COOLED CONTACT RECTIFIER .

Filed Aug. 25, 1938

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Patented Nov. 7, 1939

2,179,293

UNITED STATES PATENT OFFICE

2,179,293

COOLED CONTACT RECTIFIER

Carl C. Hein, Forest Hills, Pa., assignor to Westinghouse Electric &amp; Manufacturing Company, East Pittsburgh, Pa., a corporation dt Pennsylvania

Application August 25, 1938, Serial No. 226,645

Claims. (Cl. 175—366)

My invention relates to contact rectifiers and especially copper oxide contact rectifiers.

An object of the invention is to provide effective cooling for contact rectifiers.

The useful life of a contact rectifier utilized for the conversion of alternating current into direct current is a function of the operating temperature. .

A high temperature of operation means rapid 10 depreciation and short life while, on the other hand, low temperature of operation means slow depreciation and consequent long life, resign practice is to specify a maximum operating temperature. If this is 45° C. and the ambient-tem•lo perature is 30°, there is only a 15° gradient between the two. This necessarily limits the output to a conservative valve because of the «mail difference between the two temperatures. I have devised various modifications whereby with water 20 cooling the gradient is increased. Flowing water at 15° C. with its greater gradient will provide more rapid heat transfer and the stream of water will more rapidly remove this heat from the rectifier at a much greater rate than in the 25 Prior art with a resultant increase of output of the order of 10 fold so that currents of the order of 25 amperes average direct current are obtained wth a 1%-inch copper oxide element operating at the temperature range now used in design 30 specifications.

The preferred embodiments of my invention are disclosed in the drawing and these modifications will also illustrate particular advantages of my invention.

Figure 1 is a side view partly in elevation and Partly in cross section of a preferred embodiment of my invention;

Mg. 2 is a sectional view taken on lines Π—H of Mg. 1;

⁴⁰ x. F*^{8- 3 ls a} “to® ^elevational view of a modification of my invention;'

Mg. 4 is a cross sectional view of another modification of my invention;

⁵ ί? ^{a cr}^^se?^ttonal view of a still further 45 modification of the invention; and

Mg. 6 is a front elevational view thereof.

• 1 illustrated the double plate or ’ disk 10 with an electronically condimting wm. pound II formed thereon. I prefer to utilize 50 copper for the electrode It and copper oxide for the.electronically conducting compound formed on the metal member 10. Other types of contact rectifiers may be used if desired, such as those employing selenium or compounds of sulphur for 55 the layer I I. Joined thereto I usp a _r]_nt_e member 12 and in case of an assembly of several units, this contact member also bears against another metal member 12 with its electronically connecting compound 14. The contact member 12 preferably has a larger area than the copper s plate iO with its oxide layer II. The structure of the disk is preferably that of flat annular rings having a central opening 15 for the passage of a bolt 16 therethrough having suitable tightening nuts 17. To the outer annular area 10 18 of the contact member 12 is secured a container 19 having a cooling medium preferably in the form of a hollow tubular member extending around the major portion of the periphery 18 and welded or soldered integrally to the con- 15 tact member. The tubular member 18 has offset ends 20 for the attachment of a hose or other connection 21 of insulating· material to pass a cooling medium, such as water or a refrigerant, through the hollow tubular member 18 and to’ 20 withdraw this cooling medium therefrom. Where a series of elements are utilized as in Mg. 1, the container on the contact member may be connected in series or parallel with the other tubular members of the other units. The con- 25 tact member 12 is preferably of copper.

Various contact discs or extensions 22, 23, 24, 25 and 26 may be utilized as desired. The arrangement in Mg. 1 is adapted to have an alternating current system applied to its termi- 30 nals 22 and 23. The current will enter at 22 and pass through a copper oxide’ unit into the positive terminal 25. The return current ftom the direct current load will pass from the contact 24 through the copper oxide units to the 35 alternating contact 23. The next half cycle the alternating current entering at 23 will pass through the copper oxide unit to the positive contact 25 and the return current from the direct current load will enter contact 26 and pn.« ₄₀through the rectifying units to the alternating current contact 22.

In Mgs. 1 and 2, I have placed certain preferred dimensions as illustrative and hot as limiting my invention thereto. 45

In Mgs. 3 and 4,1 have illustrated the metal disc 30 having its electronically conducting compound 31 formed thereon and in contact with a container 32. This container is preferably in the form of a hollow casing having a passage for 50 the circulation of water therethrough from an inlet 33 to an outlet 34 and to the next casing by means of a hose 21. The casing is preferably that of two annular plates 35 and 36 with a rim portion 37 and a hub portion 31. The hub por- 55

3,179,293 tion 38 is perforated for the passage of bolt 39 therethrough and the bolt 39 has suitable binding nuts 40 thereon. Suitable electrical connecting discs 41 may be spaced as desired for the purpose of electrical connections to the contact rec⁵ tifier.

In Fig. 5, I have illustrated a modification of the invention of Fig. 4, in which the electronically conducting compound 50 is formed directly _ upon the sides 51 of the container 52 otherwise constructed similar to the container 32 in Figs. 3 and 4.

Fig. 6 illustrates how the electronically conducting compound may be formed on the circular disk 51 and then the circular disk attached by screws S3 to the casing of the controller 52.

At certain times a warm or hot medium may be circulated through the conduits as in outdoor installations in winter time or where a certain temperature is necessary for tests.

^M It is apparent that many modifications may be made in the form, arrangement and numbers of elements disclosed in the preferred embodiments specifically illustrated in the drawing. As 2g an example, the disk 10 in Fig. 1 may be % inch thick, but if it is not desired to utilize this thickness for the copper plate, then a thinner disk .05 inch thick may be used with an accessory spacer of inexpensive metal, such as iron, about % inch thick. The copper contact plate 12 must be thick enough to support the tubular member 19 and also thick enough to carry off the heat developed and yet not too thick to add to the cost of the device. The thickness can be from %e inch to %₂ inch, preferably about 50 mils. The strips 22, 23, 24, 25 and 26 can be very thin, as of %*- ₅inch copper. Accordingly, I desire only such limitations to be placed on the following claims as are necessitated by the prior art.