FUNCTION
PROPORTIONAL CONTROL EQUIPMENT The proportional controller (3) controls the drive current of solenoids A and B for the proportional control solenoid valve (4) by using the built-in current control circuit (PWM control), in response to the proportional signals input by the tilted proportional lever (2), according to the solenoid drive current control diagram.
The secondary pressure from the ports A1 and A2 of the proportional control solenoid valve (4) enters the pilot port of the control valve (auxiliary) (5) to control the spool. This allows the operator to control the flow rate of the hydraulic oil in the auxiliary lines A and B by operating the proportional lever (2) at certain angles.
When the button A (6) or B (7) of the left pilot valve is pressed, the maximum solenoid drive current can be output for the proportional control solenoid valve (4), despite the size of the signals input by the proportional lever (2). Pressing the button A (6) outputs the maximum current for solenoid valve A. Pressing the button B (7) outputs the maximum drive current for solenoid valve B. At that time, the flow rate of the auxiliary line A or B becomes maximum. Pressing the left button (6) for the second time holds the maximum flow rate. Pressing the button once again returns to the neutral position.
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