| 摘要 |
PURPOSE:To manufacture a seamless, homogenized, hollow diaphragm with excellent strength by a method wherein a core constituting hollow inside is made of a specific material. CONSTITUTION:The material comprising a core 14 made of paraffin with melting point of 68-72 deg.C is formed into one body with a supporter 10. When non hardened solution of room temperature hardening type urethane elastomer is injected from an injecting port 28 of a formed and assembled body, the non hardened solution is polymerized to be hardened in a cavity 22 producing elastic urethane elastomer corresponding to the shape of the cavity. The core 14 may keep its shape while the urethane elastomer is formed into one body with the supporter 19 since the temperature rise due to polymerizing reaction is restricted below the melting point of the paraffin comprising the core 14. Then a hollow diaphragm 32 is manufactured by means of heating a formed body released from the core 14 to melt and discharge the paraffin as well as sticking the supporter 10 to a hollow inside 30 forming them into one body. |
