PURPOSE: To reduce man-hour and to permit the easy control of sizes by brazing a raw material of a back cover engaging member to the lower step on the inside circumference of a sintered blank of a case band then finishing simultaneously the inside circumferential part of the case band and back cover engaging member to the finish inside circumferential surface.
CONSTITUTION: The lower step 1'a on the inside circumference of the sintered raw material blank 1' of the case band 1a is formed by electric discharge machining and the raw material 2' of the back cover engaging member 2 is brazed to the step 1'a. The inside circumference of the blank 1' and the inside circumference of the raw material 2' are finished by electric discharge machining to the finish inside circumferential shapes 1'b, 2'a. The base parts are further ground to the surfaces 1'c, 2'b. The surfaces are then worked with a chamfer groove, etc. As a result, the man-hour of the electric discharge machining is decreased and the stage for machining the inside circumference of the back cover engaging member is omitted and therefore the number of stages is decreased and since the members are simultaneously worked by electric discharge machining, the control of the accuracy of the inside circumferential size is made easy.
| JPS5846716 | [Title of the Invention] Clock device |
| JPS5582979 | CONSTRUCTION OF PACKAGE |
SUZUKI KAZUHARU
HAYASHI JUNICHI
HAYANO KIJURO
SEIKO EPSON CORP