| 摘要 |
595,536. Asymmetrically-conducting resistances. WESTINGHOUSE BRAKE & SIGNAL CO., Ltd., and THOMPSON, L. E. July 6,1945, No. 17266. [Class 37] In a dry contact rectifier a continuous thin strip or band 4 of insulating material is applied to the edge of a base plate 1 so as to overlap the adjacent edge of a counter electrode 3, and a protective layer 5 of non-porous metal or alloy is applied by spraying &c., to cover the remaining portion of the electrode and extend over the insulating strip. Access of moisture &c. to the rectifying boundary between the selenium or other coating 2 and the counter electrode 3 is thus prevented. The invention is also applied to a rectifier element with a central fixing hole (Fig. 2, not shown), the rim round the hole being protected with an insulating strip. The non-porous metal may also be applied so as to form a seal between the strip 4 and the base 1. The Provisional Specification describes also a rectifier element in which a flexible protecting plate is used in place of the sprayed-on metal. In another form a thin plate of the same shape and area as the counter electrode is applied to the latter and the edges of the element sealed with insulating material. The edges of the protecting plate may be flanged or grooved to provide a channel which is filled with the sealing material. |
