| 摘要 |
641,959. Piezo-electric crystals. BRUSH DEVELOPMENT CO. June 24, 1947, No. 16639. Convention date, June 24, 1946. [Class 40 (viii)] A crystal element is covered by a moistureproof wrapping 26<SP>1</SP> that extends beyond at least one edge face to form a cavity having this face as its bottom and through which the electrode leads 24<SP>1</SP>, 25<SP>1</SP> and 39 pass, the cavity being sealed by a moisture-proof fillet. The element shown is a twin-plate flexing element and the wrapping is a metallic foil coated on both sides with an insulating film. The cavity is sealed with wax. The Specification also describes a jig for positioning the leads. |
