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| Illustration 1 | g00565422 |
Section View Of The Vibratory Pump (1) Shaft. (2) Bearing. (3) Pump housing. (4) Swashplate. (5) Joint pin. (6) Servo housing. (7) Servo piston. (8) Barrel. (9) Solenoid valve. | |
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| Illustration 2 | g00565446 |
Section View Of The Servo Piston (6) Servo housing. (7) Servo piston. (10) Springs (centering). (11) Piston rod. (12) Stroke limiter screw. (13) Locknut. | |
The servo control assembly controls the swashplate angle (4) of the vibratory pump. The servo housing (6) is an integral part of the vibratory pump. The servo housing (6) contains the servo piston (7) .
The charge circuit supplies control oil to the control valve (9) on the vibratory pump. The control valve (9) regulates the servo piston (7) by directing the oil flow which enters the servo housing (6). The control valve (9) also acts on the servo piston (7). Linear movement of the servo piston (7) mechanically controls the rotational movement of the swashplate (4) with the joint pin (5). When the servo piston (7) moves, the angle of the swashplate (4) changes in the pump.
The flow of the pump output is zero when the swashplate angle is zero. The swashplate angle is zero when the servo piston (7) is in the center position. The servo piston (7) will return to the center positions when the control valve (9) is not energized. The servo piston (7) is mechanically centered by the springs (10). The center position of the servo piston (7) can be adjusted by loosening the locknut (13) and turning the piston rod (11) .
The pump flow is controlled by the servo piston (7). The maximum pump output is determined when the swashplate (4) is at the maximum angle. The maximum swashplate angle is controlled by limiting the travel of the servo piston (7). Adjust the stroke limiter screw (12) in order to control the travel of the servo piston. There are two stroke limiter screws. The screws determine the direction of travel for the servo piston (7). The stroke limiter screws (12) are located on each end of the servo housing (6).