| 摘要 |
<p>Without changing the structure of a gas laser, the loss torque of a magnetic seal, the size of the driving motor of a gas circulating fan, the size of a gas laser as a whole and the power consumption are reduced. A control unit (1) supplies an ON/OFF signal (S1) to the valve (4) to close the valve (4), makes cooling water flow into the surrounding of a magnetic seal part (3b) and allows the temperature rise of the magnetic seal part (3b). Then the control unit (1) supplies a rotational speed instruction signal (S2) instructing an initial low rotational speed to a motor driving amplifier (2b) and monitors the driving torque (τm) of a fan driving motor (2a). When the driving torque reaches a predetermined lower limit driving torque value after a peak value, the control unit (1) increases the rotational speed gradually and issues an instruction of a steady rotational speed at the steady rotation to the motor driving amplifier (2b). The control unit (1) monitors a temperature signal (Tm) from a temperature sensor (9) and controls the opening and closing of the valve (4) so as to keep the temperature within a required range.</p> |
