Illustration 1 | g00791239 |
The Illustration above shows the Tilt System when the Quick Coupler is being Tilted Backward. (1) Diverter valve (2) Coupler cylinder (quick coupler) (3) Load control valve for coupler cylinder (4) Bank valve (5) Signal relief valve (6) Line (load sensing) (7) Work tool cylinder (8) Rear section of stabilizer control valve (9) Front section of stabilizer control valve (10) Stabilizer control valve (11) Stabilizer cylinder (right side) (12) Stabilizer cylinder (left side) (13) Load control valve for left side stabilizer cylinder (14) Load control valve for right side stabilizer cylinder (15) End section of bank valve (16) Joystick (17) Implement section of bank valve (frame leveling) (18) Dual stage relief valve (19) Relief valve (coupler tilt) (20) Implement section of bank valve (boom extend/retract) (21) Pilot control valve (22) Solenoid valve (23) Solenoid valve (24) Solenoid valve (25) Solenoid valve (26) Pressure reducing valve (27) Brake reservoir (28) Hydraulic tank (29) Piston pump (30) Filter (31) Line (load sensing) (32) Inlet section of bank valve (33) Metering pump (34) Compensating cylinders (35) Valve (quick coupler pins) (36) Implement section of bank valve (boom raise/lower) (37) Load control valve for telescoping cylinder (38) Boom cylinder (boom raise/lower) (39) Implement section of bank valve (coupler tilt) (40) Load control valve for boom cylinder (41) Relief valve (coupler tilt) (42) Relief valve (43) Telescoping cylinder (boom extend/retract) (44) Implement section of bank valve (auxiliary section) (45) Valve (46) Load control valve for frame leveling cylinder (47) Frame leveling cylinder (48) Load control valve for tilt cylinder (49) Tilt cylinder (coupler tilt) (PP) Pump delivery (CP1) Tilt cylinder pressure (R) Return oil (S) Suction oil (P) Pilot oil (LS) Load sensing oil |
Implement section (39) of bank valve (4) is used for tilting the quick coupler. This section is operated by pilot oil pressure from joystick (16).
Illustration 2 | g00739330 |
Location of Switch (Coupler Tilt) |
The joystick is moved left in order to tilt the quick coupler backward and the joystick is moved right in order to tilt the quick coupler forward. These movements are performed with the switch on the front of the joystick, pressed. The switch on the front of the joystick energizes solenoid valves (22), (23) and (24) .
Pilot pressure (P) is transmitted from the joystick through solenoid valve (24) to implement section (39) of bank valve (4) .
Oil (CP1) flows from implement section (39) through valve (45) and through load control valve (48) to the piston side of the tilt cylinder. As the tilt cylinder extends, the quick coupler is tilted backward and oil (R) flows from the rod side of the tilt cylinder through valve (45), through bank valve (4), and through filter (30) to hydraulic tank (28) .
Pressure in the tilt system is transmitted to the load sensing resolver network of the bank valve and the highest load pressure of the systems in operation adjusts the output of the piston pump.
When the joystick is moved to the HOLD position, load control valve (48) is closed by spring force, locking oil into the piston side of the tilt cylinder in order to hold the quick coupler at the selected angle.
When a forward tilt of the quick coupler is selected, oil flows to the rod side of the tilt cylinder. The load control valve is piloted open by oil pressure that develops in the rod side of the tilt cylinder. Oil then flows from the piston side of the tilt cylinder through valve (45), through bank valve (4), and through filter (30) to hydraulic tank (28) .
The load control valve meters oil from the piston side of the tilt cylinder in proportion to the pressure in the rod side of the tilt cylinder in order to regulate the selected speed of the cylinder. This function also prevents a sudden forward tilt of the quick coupler. If the quick coupler is being tilted and the flow of oil to the tilt cylinder fails, the load control valve will be closed by spring force.