HARNESS AS-ENGINE 1306614 - Caterpillar

Illustration 1 g00477369
Swing motor (left view) (1) Shock reducing valve (stick out) (2) BodyShock reducing valve (1) functions in order to prevent a shock load at the end of the movement of the cylinder rod. The shock load is reduced by restricting the return flow of pilot oil from the stick control valve. Shock reducing valve (1) is in body (2). Shock reducing valve (1) is located beside the side plate of the upper frame. Pilot oil that is returning from the control valve is restricted by the shock reducing valve. Because the stem of the control valve closes gradually, oil flow in the pilot line gradually stops. The stick stops gradually in order to prevent shock loads.
Illustration 2 g00477370
Shock reducing valve (3) Flow control valve (4) Port (pilot control valve) (5) Spring (6) Check valve (7) Orifice (8) Port (control valve) (9) Spring (10) Passage (11) ValveWhen the control lever is moved to STICK OUT position, shock reducing valve (1) receives pilot oil through port (4). The pilot oil pressure moves valve (11) to the left against the force of spring (5). The movement of valve (11) to the left opens passage (10). The pilot oil goes through passage (10) and out port (8) to the control valve. Valve (11) functions as check valve (6) .When the control lever is returned to the NEUTRAL position, pilot oil in the control valve returns to port (8). The return pilot oil pressure then moves valve (11) to the right against the force of spring (9). The movement of valve (11) to the right closes passage (10). The pilot oil goes through orifice (7) to port (4). Valve (11) functions as flow control valve (3). The oil flow is restricted by orifice (7). Orifice (7) slows down the movement of the stem of the stick control valve. The oil flow in the return circuit of the stick cylinder also slows down. The slow flow of the oil absorbs the shock loads at the end of the movement of the cylinder rod.