摘要 |
To obtain a polyester elastomer compression spring which does not exhibit significant permanent set when compressed by more than ten per cent, a precompression force is applied to a moulded block of the elastomer sufficient to compress the block to an extent greater than thirty per cent of the original dimension of the block as measured parallel to the precompression force. The force is then removed. The block is moulded from pellets of the elastomer. While the block is solidifying, pressure is supplied to the central portion. The block is then subjected to heat treatment, before the precompression force is applied. The precompression force can be used to bond the block between two apertured end plates. <IMAGE> |