COIL AS-CONDENSER 1248492 - Caterpillar

Illustration 1 g00484634
(1) Opening from the control valve (2) Orifice in the check valve (3) Check valve (4) Opening to the rod end of the bowl cylinder (5) Opening to the head end of the bowl cylinder (6) Spring chamber (7) Passage from the control valve (8) Check valve that vents to the tankThe check valve is located on the bowl cylinder. The carry-check valve will keep the bowl in any position. In order for the carry-check valve to work, the valve spool for the bowl must be in the HOLD position. The HOLD position of the bowl valve spool stops the oil in the vent line to check valve (8). Then, check valve (8) cannot open. When check valve (8) is closed, the oil from the rod end of the cylinder cannot flow from opening (4) to the tank and the bowl will not move.Check valve (8) is open to the tank only when the bowl valve spool is in the LOWER position. The pump oil flows through passage (7) from the control valve and passes through opening (5). The oil then enters the head end of the bowl cylinders. The oil in the head end of the cylinders moves the pistons and rods in order to lower the bowl. Oil from the rod end of the cylinders enters opening (4). The oil flows through orifice (2) into check valve (8). From check valve (8), the oil flows into the line that is open to the tank. The oil from the rod end of the cylinder flows to the control valve and into the tank.When the bowl valve spool is moved to the RAISE position, the pump oil from the control valve flows through opening (1) and opens check valve (3). The check valve opens because the oil from the head end of the cylinder is open to the tank and the pump pressure is greater than the pressure of the oil and the spring in spring chamber (6) .The pump oil flows past check valve (3) through opening (4) into the rod end of the cylinder. The pump oil moves the piston and rod, which raises the bowl. The oil from the head end of the cylinder flows through opening (5) and into passage (7). From passage (7), the oil flows to the control valve then to the tank.