| 摘要 |
PURPOSE:To permit the sufficient vibration of a vibration element by making the wave shape of the voltage applied into the vibration element into trapezoidal or triangular pulse wave form in which each of the starting-up part and the starting-down part has a constant gradient. CONSTITUTION:A piezoelectric vibrator is used for the pressing part of a liquid, gas or powder pump. The vibration element of the piezoelectric vibrator is constituted of a unimorph piezoelectric vibration element 1. The applied-voltage control circuit for the vibration element 1 receives a certain amount of electric current from a transistor Tr1 through a full-wave rectifying circuit 3 and a constant-current power-source circuit 4 from an a.c. power source 2. A square wave is obtained from the first arithmetic amplifier CI1. The integration wave of the square wave is outputted from the second arithmetic amplifier CI2. The integration wave is set according to starting-up time T2 and the starting-down time T1 according to the capacity value of a condenser C3 and controls a transistor Tr2. The vibration element 1 is driven-controlled by the operation of the transistor Tr2. |
