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| Illustration 1 | g06008357 |
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Material Feed Hydraulic Schematic in Hold (1) Left conveyor motor (2) To cooler bypass manifold port "J" (3) To port "E" cooler bypass manifold (4) Left material feed pump (5) Left auger motor (6) From port "L3" right feeder pump (7) Left conveyor rotating group (8) Reverse makeup and relief valve (left conveyor pump) (9) Forward makeup and relief valve (left conveyor pump) (10) Makeup valve (11) Relief valve (12) Reverse solenoid (13) Direction control valve (left conveyor pump) (14) Charge relief valve (15) To right material feed pump port "E" (16) Servo piston (17) Direction control valve (left auger pump) (18) Forward solenoid (19) To return manifold port "C" (20) From charge pump (21) Charge filter (22) Forward makeup and relief valve (left auger pump) (23) Left auger rotating group (24) Reverse makeup and relief valve (left auger pump) | |
The upper right pump stack contains the left material feed pump. The left pump contains left conveyor rotating group (7) and left auger rotating group (23). When the engine is running, the rotating groups in the left material feed pump rotate. Charge pump (20) provides charge oil to the material feed pumps through the vibratory manifold.
Inside the material feed pump, charge oil flows to the following locations:
- Reverse makeup and relief valve (8)
- Forward makeup and relief valve (9)
- Charge relief valve (14)
- Forward makeup and relief valve (22)
- Reverse makeup and relief valve (24)
When the material feed system is in HOLD, the solenoids on direction control valves (13) and (17) are not energized. When the solenoids on the valves are not energized, the servo pistons are centered. In this case, both sides of the servo piston open to the pump case and the pump swashplate remains at minimum angle.
Charge oil that enters the makeup and relief valves acts against the makeup valve. Since the material feed pump rotates while the engine is running, normal leakage occurs in the auger circuit and in the conveyor circuit. When pressure in the auger circuit and pressure in the conveyor circuit falls below charge pressure, the makeup valves open.
When charge pressure increases to the relief setting, charge relief valve (14) opens. When the charge relief valve is open, excess charge oil is directed into the pump case drain.
The upper left pump stack contains the right material feed pump. This pump contains the rotating group for the right conveyor and rotating group for the right auger. Charge pump (20) provides charge oil to the right material feed pump.
The material feed pump in the upper right pump stack follows the same general principles of operation as pumps in the upper left pump stack. However, on the right material feed pumps port configuration is as follows:
Port "A" - reverse port for right auger motor
Port "B" - forward port for right auger motor
Port "C" - forward port for right conveyor motor
Port "D" - reverse port for right conveyor motor
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| Illustration 2 | g06008359 |
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Material Feed Hydraulic Schematic for Conveyor and Auger Forward (1) Left conveyor motor (2) To cooler bypass manifold port "J" (3) To port "E" cooler bypass manifold (4) Left material feed pump (5) Left auger motor (6) From port "L3" right feeder pump (7) Left conveyor rotating group (8) Reverse makeup and relief valve (left conveyor pump) (9) Forward makeup and relief valve (left conveyor pump) (10) Makeup valve (11) Relief valve (12) Reverse solenoid (13) Direction control valve (left conveyor pump) (14) Charge relief valve (15) To right material feed pump port "E" (16) Servo piston (17) Direction control valve (left auger pump) (18) Forward solenoid (19) To return manifold port "C" (20) From charge pump (21) Charge filter (22) Forward makeup and relief valve (left auger pump) (23) Left auger rotating group (24) Reverse makeup and relief valve (left auger pump) | |
When the left conveyor is operating in FORWARD, the forward solenoid is energized. Charge oil flows across direction control valve (13) and into the forward servo piston cavity. In this case, the swashplate moves and left conveyor rotating group (7) produces flow.
Left conveyor rotating group (7) sends flow out port "A" of the pump housing. Oil flow is directed to port "B" of left conveyor motor (1). The pressure differential between the forward and reverse sides of the motor causes the motor to turn. After turning the motor, oil at reduced pressure is directed out port "A" of the motor housing to port "B" of the material feed pump.
Loop flushing occurs at the low-pressure side of left conveyor motor (1). Oil in the low-pressure circuit flows through an orifice and into the case of the motor. Loop flushing flow is approximately
As loop flushing occurs, pressure in the return circuit falls below charge pressure. Charge pressure opens the makeup valve in reverse makeup and relief valve (8). Oil from the charge system replenishes the oil lost in the circuit due to loop flushing.
As long as pressure in the forward circuit is greater than charge pressure and less than relief pressure, makeup valve (10) remains seated. In this case, relief valve (11) remains closed. If forward circuit pressure rises above relief pressure, the relief valve opens an excess pressure is purged into the charge circuit.
Left auger rotating group (23) sends flow out port "D" of the pump housing. Oil flow is directed to port "B" of left auger motor (5). The pressure differential between the forward and reverse sides of motor causes the motor to turn. After turning the motor, oil at a reduced pressure flows out port "A" of the motor housing to port "C" of the material feed pump.
Loop flushing, makeup, and relief functions in the auger circuit are identical to the conveyor circuit.
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| Illustration 3 | g06008368 |
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Material Feed Hydraulic Schematic for Conveyor and Auger Reverse (1) Left conveyor motor (2) To cooler bypass manifold port "J" (3) To port "E" cooler bypass manifold (4) Left material feed pump (5) Left auger motor (6) From port "L3" right feeder pump (7) Left conveyor rotating group (8) Reverse makeup and relief valve (left conveyor pump) (9) Forward makeup and relief valve (left conveyor pump) (10) Makeup valve (11) Relief valve (12) Reverse solenoid (13) Direction control valve (left conveyor pump) (14) Charge relief valve (15) To right material feed pump port "E" (16) Servo piston (17) Direction control valve (left auger pump) (18) Forward solenoid (19) To return manifold port "C" (20) From charge pump (21) Charge filter (22) Forward makeup and relief valve (left auger pump) (23) Left auger rotating group (24) Reverse makeup and relief valve (left auger pump) | |
When the left auger is operating in REVERSE, the left auger reverse solenoid is energized. When the reverse solenoid is energized, charge oil flows across direction control valve (17) into the reverse servo piston cavity. In this case, the swashplate moves and left auger rotating group (23) produces flow.
Left auger rotating group (23) send flow out port "C" of the pump housing to port "A" of left auger motor (5). The pressure differential between the forward and reverse sides of the motor causes the motor to turn. After turning the motor, oil at a reduced pressure flows from port "B" of the auger motor to port "D" of the material feed pump.
When the auger is operating in REVERSE, loop flushing occurs at the high-pressure side of left auger motor (5). Oil in the high-pressure circuit flows through an orifice and into the case of the left auger motor. The case drain of the left auger is connected to oil cooler bypass manifold (3).
As loop flushing occurs, oil is depleted from the hydrostatic loop. This action causes pressure in the return circuit to fall below charge pressure. Charge pressure opens the makeup valve in forward makeup and relief valve (22). Oil from the charge circuit replenishes oil lost due to loop flushing.
As long as pressure in the reverse circuit is greater than charge pressure and less than relief pressure, makeup valve (24) remains seated. In this case, the relief valve remains closed. If reverse circuit pressure rises above relief pressure, the relief valve opens an excess pressure is purged into the charge circuit.
Left conveyor rotating group (7) sends flow out port "B" of the pump housing. Oil flow is directed to port "A" of left conveyor motor (1). The pressure differential between the forward and reverse sides of the motor causes the motor to turn. After turning the motor, oil at a reduced pressure flows out port "B" of the motor housing to port "A" of the material feed pump.
Loop flushing, makeup, and relief functions in the conveyor circuit are identical to the auger circuit.