| 摘要 |
1469019 Compression moulding metal powder EBERHARD JAEGER KG 11 Nov 1974 [16 Nov 1973] 48792/74 Addition to 1359875 Heading B5A [Also in Division C7] A mould for pressing a metal powder, e.g. Cu + W around a mandrel according to the process of Specification 1,359,875 comprises a die 1 with a through bore 5, a mandrel 4 which in the compacting position extends through the bore and engages guide bores 6 and 23 in lower and upper punches 2 and 3 so that the mandrel can be pushed into one of the punches against the action of a force which tends to push it out of the punch. In the preferred embodiment the upper punch comprises a core bar 12 supported on a pressure pad 13 and mounted inside a tube 11 which is connected to a slide 14 which is pressed against stop 17 by a helical spring 16. The mandrel 4, e.g. a wire 180 mm. long x 0À8 mm. gauge is rigidly connected to a sliding block 21 at the lower end of a helical compression spring 20 in the bore 19 of core bar 12. A plug 22 screwed into the end of the core bar 12 has a guide bore 23 for the mandrel. During compaction of metal powder in the die, when the lateral pressure of the powder on the mandrel is such that the resistance to motion of the mandrel is greater than the force of spring 20, then the spring is compressed and the axial force on the mandrel is thus kept small and buckling of the mandrel is prevented. The lower punch 2 has a drainage bore 7 for removing powder from the guide channel 6. |
