Variable-Speed Switch - Hitachi W 6VM Technical Data And Service Manual

7-6. Variable-speed Switch

This switch is equipped with a variable speed control circuit. Through the control circuit, the speed can be
controlled up to 65 % of maximum speed according to the degree at which the switch is depressed.
A disadvantage of this system is that if the bit becomes locked resulting in stoppage of the motor, the speed
control circuit may be burnt out. In such a case, the switch should be released immediately or turned OFF. To
avoid damage to the switch circuit, the customer should be advised to increase driving speed gradually until the
screw is driven approximately halfway into the workpiece, then depress the trigger to obtain optimum speed.
100 %
Maximum speed change point
65 %
0
Trigger stroke
Fig. 4
Switch characteristics (Approximately shown converted into the linear line)
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