FASTENER GP 4722526 - Caterpillar

Ejector Return
When valve spool (6) in control valve (3) is moved to either RETURN position (B), or RETURN, detent position (A), the pump oil goes around the valve spool and through line (4) to the rod end of ejector cylinder (8). (No illustration for this operation.) The pump oil in the rod end of the cylinder moves the piston which pulls the ejector toward its retracted position in the bowl. The piston pushes the oil from the head end of the cylinder through line (1), around valve spool (6) and through line (2) into filter (11) and hydraulic tank (15).
SPRING HOUSING ON CONTROL VALVE
6. Valve spool. 17. Detent balls (four). 18. Kickout valve. 19. Chamber. 20. Retainer. 21. Retainer. 22. Spring.When valve spool (6) is in RETURN, detent position (A), detent balls (17) keep the valve spool in the RETURN, detent position (A), until the moving piston in ejector cylinder (8) is stopped in the head of the cylinder. When the piston stops, there is an increase in the pressure of the pump oil in the circuit to the rod end of the cylinder. The pump oil is also in a passage in valve spool (6). When the increase in the pressure of the pump oil gets to approximately 1600 psi (112.5 kg/cm2) (11040 kPa), the oil opens kickout valve (18) and goes into chamber (19). The chamber is between retainers (20) and (21). The pressure of the pump oil moves retainer (20). Retainer (21) is against spring (22) and is not easy to move. Retainer (20) moves valve spool (6) beyond detent balls (17), and then spring (22) moves valve spool (6) to HOLD position (C).Loosen the screw, that holds kickout valve (18) and the valve spring, when the pressure of the oil which opens kickout valve (18) is too high. Tighten the screw when the pressure of the oil which opens the kickout valve is too low. Earlier control valves have shims between the spring and kickout valve (18) which are used to adjust the pressure setting of the kickout valve.Apron Circuit
SCHEMATIC OF APRON CIRCUIT IN APRON LOWER POSITION
1. Line to head end of apron cylinder. 2. Line to filter and hydraulic tank. 3. Control valve. 4. Passage