| 摘要 |
<p>1283717 Die sets PORTER PRECISION PRODUCTS CO 5 Aug 1969 [11 Sept 1968] 39217/69 Heading B3W The upper and lower shoes 13 and 15 of a die set are located by a plurality of guide post assemblies 10, each of which comprises a tubular sleeve 25 attached to one of the shoes and slidable within a bush 26 attached to, or formed as a bore in, the other shoe, spring means, such as a solid cylindrical polyurethane member 33, within the sleeve tending to urge the shoes apart by bearing at one end on a member rigid with the shoe to which the sleeve is attached and at the other on the head 36 of a pin 27 which is fixed relatively to the bush 26. As shown, Fig. 2, the spring 33 bears on a back-up plate 12 and the lower die shoe 15 is clamped at 42 to a bolster plate 31 on which the pin 27 bears. In an alternative form of guidepost assembly, Fig. 7 (not shown), the sleeve is secured to the upper die shoe by means of a bush (51) and is axially aligned within the bush (55) mounted on the lower die shoe by means of roller bearings (60) in a inner bush (58). A punch 14 is mounted on shoe 13, which is not attached to actuating ram 47, and a die 16 is mounted on shoe 15. A stripper plate 17 rigidly secured to the die is recessed at 18 to receive a workpiece 20. During punching the springs 33 are compressed to the shape shown in Fig. 2 and, in regaining their shape as shown in Fig. 4 as the ram 47 is raised, lift the upper die shoe 13 and back-up plate 12 and cause the workpiece 20 to be stripped from punch 14 by plate 17. To provide additional stripping force, each sleeve 25 may be surrounded by a poly. urethane bush (not shown) which is compressed during punching between the bush 26 and the shoe 13.</p> |
