| 摘要 |
PURPOSE:To protect a piezoelectric ceramic oscillator against crack by compos ing the oscillator in stator of a fiber reinforced metal having coefficient of thermal expansion approximately same as that of the piezoelectric ceramic oscillator in the stator. CONSTITUTION:An oscillator 11 constituting a stator 14 is composed of fiber reinforced metal having coefficient of thermal expansion approximately same as that of a piezoelectric ceramic oscillator 12 within the adhesion temperature range 40-250 deg.C of a thermosetting adhesive 13. The oscillator 11 is composed, for example, of a carbon fiber reinforced aluminum alloy where the volumetric content of carbon fiber is 10-70% and the coefficient of thermal expansion is 1.0X10<-6>-3.0X10<-6>. Since the oscillator 11 and the piezoelectric ceramic oscilla tor 12 expand substantially equally when they are heated during adhesion proc ess, thermal stress is reduced between them. |
