CONTROL GP-HANDLE 1879880 - Caterpillar

Illustration 1 g01100860
The ejector circuit with control valve (3) in RETURN position (B) (1) Line to head end of ejector cylinder and rod end of the floor cylinder (2) Line from the control valve to the filter and the tank (3) Control valve (4) Valve spool for the elevator motor (5) Line to the rod end of the ejector cylinder (6) Ejector cylinder (7) Valve spool for ejector and floor cylinders (8) Floor cylinder (9) Pump oil line for steering circuit (10) Valve spool for bowl cylinders (11) Check valve (12) Filter (13) Relief valve (14) Seat and spring (15) Hydraulic oil tank (16) Pump for implements and steering (A) RETURN detent position (B) RETURN position (C) HOLD position (D) FORWARD position (AA) Pump oil (BB) Tank oilEjector Return
When valve spool (7) is moved to RETURN position (B) or RETURN detent position (A) oil will flow from pump (16) around valve spool (7) and through line (5). The oil that flows through line (5) flows to the rod end of ejector cylinder (6). The oil then flows through check valve (11). The pump oil moves seat (14) that is held closed by the spring. The oil flows though the check valve and the oil flows into the head end of floor cylinder (8). The pump oil in the head end of floor cylinder (8) moves the piston in floor cylinder (8) in order to close the floor. The pump oil in the rod ends of ejector cylinder (6) moves the piston in ejector cylinder (6) in order to pull the ejector to the return position in the bowl. The moving pistons in cylinder (6) and cylinder (8) push the oil through line (1). The oil then flows around valve spool (7). The oil flows through line (2). Finally, the oil flows through filter (12) and into hydraulic tank (15).
Illustration 2 g01100872
Spring housing on control valve (3) (7) Valve spool (17) Detent balls (18) Kickout valve (19) Chamber (20) Retainer (21) Retainer (22) SpringWhen valve spool (7) is in RETURN detent position (A), detent balls (17) keep valve spool (7) in RETURN detent position (A). When the moving piston in ejector cylinder (6) is stopped by the head end of the cylinder, there is an increase in the pressure of the oil line (5). Also, when the moving piston in floor cylinder (8) is stopped by the rod end of the cylinder, there is an increase in the pressure of the oil line (5). There is also an increase in pressure in the pump oil around valve spool (7). When the pressure of the pump oil reaches 13200 kPa (1900 psi), the pump oil in valve spool (7) opens kickout valve (18) and flows 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 retainer (21) is not easy to move. Retainer (20) moves valve spool (7) beyond detent balls (17) and the spring