An improved compsite indentation hardness tester with built-in base for rubber, and the like substances such as soft or hard plastics and testile would packages

摘要

1. An improved composite indentation hardneas tester with built-in base for rubber and the like aubataneea as claimed in ray main patent No.170499 dated 18.6.'90 the improvement/ modification being in replacing the single clamping pressure spring (11), working in compression, by two or more spiral springs (l4) provided vertically 1 in between the top of base (5) and the flange of the bush (12) » to give constant load of buckling, at all the stages of pressure, thereby assuring an absolute constant clamping load On the specimen.