PISTON AS 1908377 - Caterpillar

Illustration 1 g03877961
(1) Implement ECM
(2) Boom motor
(3) Boom motor solenoid
(4) Boom motor pressure sensor
(5) Boom motor speed sensor
(6) Hook motor
(7) Hook motor solenoid
(8) Hook motor pressure sensor
(9) Hook motor speed sensor
(10) Pilot manifold
(11) Hook lower brake solenoid
(12) Boom lower brake solenoid
(13) Hook pilot pressure supply solenoid
(14) Hook free fall solenoid
(15) Hook pump raise solenoid
(16) Hook pump lower solenoid
(17) Boom pump lower solenoid
(18) Boom pump raise solenoid
(19) Implement pumpThe pipelayer winches are hydraulically driven but electronically controlled. When the operator gives a command for the winch to RAISE the boom, implement ECM (1) responds to the movement of the control. The signal that is received by the ECM from the control is a pulse width modulated (PWM) signal. The ECM sends a signal to boom pump raise solenoid (18) that corresponds to the input signal. The ECM relates a specific PWM signal to the duty cycle of the solenoid. The solenoid begins to change the angle of the swashplate in implement pump (19). The increase in the swashplate angle creates the flow of oil to boom motor (2). The ECM then monitors boom motor pressure sensor (4) and boom motor speed sensor (5). The ECM can also alter the angle of the swashplate in boom motor (2). The Swashplate angle matches the request from the operator by activating boom motor solenoid (3). When the operator gives a command for the winch to RAISE the boom, the winch brake remains applied. A one-way roller clutch allows the winch to RAISE the boom without releasing the brake.When the operator gives the command to LOWER the boom, the ECM activates boom pump lower solenoid (17). The ECM must also send a signal to boom lower brake solenoid (12) to release the winch brakes.When the operator gives a command for the winch to RAISE the hook, implement ECM (1) responds to the movement of the control. The signal that is received by the ECM from the control is a pulse width modulated (PWM) signal. The ECM sends a signal to hook pump raise solenoid (15) that corresponds to the input signal. The ECM relates a specific PWM signal to the duty cycle of the solenoid. The solenoid begins to change the angle of the swashplate in implement pump (19). The increase in the swashplate angle creates the flow of oil to hook motor (6). The ECM then monitors hook motor pressure sensor (8) and hook motor speed sensor (9). The ECM can also alter the angle of the swashplate in hook motor (6). The swashplate angle matches the request from the operator by activating hook motor solenoid (7). When the operator gives a command for the winch to RAISE the hook, the winch brake remains applied. A one-way roller clutch allows the winch to RAISE the hook without releasing the brake.When the operator gives the command to LOWER the hook, the ECM activates hook pump lower solenoid (16). The ECM must also send a signal to hook lower brake solenoid (11) to release the