| 摘要 |
<p>PROBLEM TO BE SOLVED: To control a piezoelectric resonator at desired polarization with high accuracy and also to improve productivity of the resonator with no skill required by repeating measurement of the frequency difference and application of voltage in a fixed cycle until the frequency difference is set within a cross range. SOLUTION: A piezoelectric resonator 1 held at a terminal 13 in a 1st area A of a polarization degree control device 11 is moved to a 2nd area B by a conveyor belt 12. The difference is measured between the resonance frequency and the anti-resonance frequency of the resonator 1. When it is decided that the frequency difference is larger than the cross difference, the voltage of a prescribed level is applied to the moved resonator 1 for a fixed time in an adjacent area C. These processes are repeated in both adjacent areas B and C until the frequency difference is set within the cross difference. These processes are repeated until the frequency difference becomes within the cross difference, a non-defective resonator 1 is picked up when returned to the area A. As a result, the resonator 1 can be easily controlled at desired polarization with no expertness required.</p> |
