PURPOSE: To enhance the dimensional accuracy by disposing a shaft having the length substantially equal to that of a reed screw and the outer diameter equivalent to the pitch diameter thereof and molding the reed screw integrally of resin on the outer periphery of the shaft.
CONSTITUTION: A rotor shaft 30 comprises a reed screw(RS) 31 and a rotor securing section 32. The RS 31 has a resin shaft 33 in the center and molded integrally of resin on the outer periphery thereof. The rotor securing section 32 is also molded integrally of same resin. With regard to the shaft 33, a liquid crystal polymer is molded using a metal mold with the outer diameter R1 thereof being set equal to the pitch diameter R of the RS 31 and the length L1 thereof being set substantially equal to the length L of the RS 31. This structure enhances the dimensional accuracy and realizes high accuracy feeding while sustaining the high accuracy for a long term.
TATENO TADASHI
HASHIMOTO FUMIO
