| 摘要 |
1,229,684. Making rivets; forging; drawing; riveting. EMHART CORP. 26 Nov., 1968 [11 Dec., 1967], No. 56023/68. Headings B3A, B3H, B3P and B3U. [Also in Division F2] A rivet assembly comprising a pull-stem 12 having a threaded or grooved end portion located in an axial bore of a rivet body 10 provided with a head 18 and shank 16 is subjected to a crimping operation to provide longitudinal recesses 40 spaced by longitudinal ribs 42 on the shank 16 and the ribs 42 are then subjected to the action of a shaping die 30 to ensure they project radially no further than the circumference of the remainder of the shank 16. As shown in Fig. 2, three crimping jaws 34 are arranged to be moved radially inwardly relative to a cylindrical rivet shank by axial displacement of a cylindrical member 36 in abutting engagement with inclined surfaces of the jaws 34 whereby the ribs 42 and recesses 40 are formed, the rivet assembly then being ejected by a piston 45, against the bias of a spring 51, through the shaping die 30. In use, the rivet assembly is inserted through a hole in a workpiece W and with the head 18 abutting the workpiece W the pull-stem 12 is moved to set the rivet body 10, the pull-stem 12 breaking or being completely withdrawn from the rivet body 10 when the setting is completed. |
