ELBOW 0036962 - Caterpillar

RAISE Operation
Illustration 1 g01395931
(1) Relief valve
(2) Spring
(3) Spring chamber
(4) Spool
(5) Passage
(6) Port from the control valve
(7) Passage
(8) Passage
(9) Poppet
(10) Passage to the ripper cylinder
(11) Passage
(12) Spring
(13) Check valve When the ripper control is moved to the RAISE position, high-pressure oil from the control valve flows into port (6). The oil flows from port (6) to passage (5) of relief valve (1). The oil flows through passage (5) into spring chamber (3). The pressure of the oil in combination with the force of spring (2) forces spool (4) downward. The flow of oil is blocked at relief valve (1).The oil also flows from port (6) through passage (8) to poppet (9) of check valve (13). Since the flow of oil is blocked at relief valve (1), the pressure of the oil against poppet (9) overcomes the force of spring (12) and poppet (9) shifts downward. The oil flows from passage (8) through check valve (13) to passage (11). Then, the oil flows from passage (11) through port (10) to the ripper cylinders.LOWER Operation
Illustration 2 g01395930
(1) Relief valve
(2) Spring
(3) Spring chamber
(4) Spool
(5) Passage
(6) Port from the control valve
(7) Passage
(8) Passage
(9) Poppet
(10) Passage to the ripper cylinder
(11) Passage
(12) Spring
(13) Check valve When the ripper control is moved to the LOWER position, return oil from the ripper cylinders flows into port (10). The oil flows from port (10) to passage (11). The pressure in passage (8) is less than the force of spring (12) and the pressure in passage (11). Poppet (9) of check valve (13) shifts upward.The oil also flows from port (10) to passage (7) and the oil exerts pressure on spool (4). Since the oil pressure at port (6) is less than the oil pressure at port (10), the oil pressure that is exerted on spool (4) is greater than the oil pressure in spring chamber (3) that is combined with the force of spring (2). As a result, spool (4) shifts upward. The oil flows from passage (7) through relief valve (1) to port (6). Then, the oil flows back to the control valve.