komatsu d375.docx

STRUCTURE, FUNCTION AND MAINTENANCE STANDARD

10 STRUCTURE, FUNCTION AND MAINTENANCE STANDARD

POWER TRAIN ..........................................10-2PPC CONTROL PIPING DIAGRAM ...........10-101

OVERALL DRAWING OF POWER TRAINWORK EQUIPMENT CONTROL ................10-102

UNIT ......................................................10-4HYDRAULIC TANK .....................................10-104

POWER TRAIN HYDRAULIC PIPINGPPC CHARGE VALVE ................................10-106

DRAWING .............................................10-6ACCUMULATOR ........................................10-109

DAMPER, UNIVERSAL JOINT ...................10-8PPC LOCK VALVE .....................................10- 110

TORQUE CONVERTER, PTO ....................10-10PPC VALVE ................................................10- 112

TORQUE CONVERTER VALVE ................10-18WORK EQUIPMENT CYLINDER ...............10-122

SCAVENGING PUMP ................................10-29PISTON VALVE ..........................................10-125

TRANSMISSION CONTROL ......................10-30QUICK DROP VALVE .................................10-126

TRANSMISSION ........................................10-32PIN PULLER SWITCH ................................10-128

TRANSMISSION ECMV .............................10-44PIN PULLER SOLENOID VALVE ...............10-129

TRANSMISSION LUBRICATION RELIEFBLADE CONTROL KNOB ..........................10-131

VALVE ...................................................10-50PITCH, DUAL TILT SOLENOID VALVE .....10-132

POWER TRAIN PUMP + LUBRICATIONWORK EQUIPMENT + PPC CHARGE

PUMP ....................................................10-51PUMP .....................................................10-134

STEERING, BRAKE CONTROL .................10-52MAIN CONTROL VALVE ............................10-136

TRANSFER, BEVEL GEAR SHAFT,CYLINDER STAY ........................................10-166

STEERING ............................................10-55BLADE ........................................................10-168

STEERING ECMV ......................................10-62RIPPER EQUIPMENT ................................10-174

STEERING CLUTCH, STEERING BRAKECAB MOUNT ..............................................10-176

ECMV ....................................................10-66CAB .............................................................10-177

PARKING BRAKE VALVE ..........................10-73AIR CONDITIONER ....................................10-179

SUDDEN STOPS PREVENTION VALVE ..10-74ENGINE CONTROL ....................................10-180

FINAL DRIVE .............................................10-75ENGINE CONTROL SYSTEM ....................10-181

TRACK FRAME ..........................................10-80DECELERATOR POTENTIOMETER .........10-182

RECOIL SPRING .......................................10-82HPI ENGINE CONTROL SYSTEM .............10-184

IDLER .........................................................10-84MONITOR SYSTEM ...................................10-186

TRACK ROLLER ........................................10-86MONITOR PANEL ......................................10-188

CARRIER ROLLER ....................................10-87MODE SELECTION SYSTEM ....................10-195

TRACK ROLLER BOGIE ............................10-88ELECTRICAL DEVICE ...............................10-200

TRACK SHOE ............................................10-90STEERING ELECTRONIC CONTROL .......10-202

MAIN FRAME .............................................10-92VHMS CONTROLLER ................................10-204

SUSPENSION ............................................10-94COMMUNICATION (ORB: ORBCOMM)

WORK EQUIPMENT HYDRAULIC PIPINGCONTROLLER/ANTENNA ....................10- 211

DIAGRAM ..............................................10-97

10-1D375A-5STRUCTURE, FUNCTION ANDMAINTENANCE STANDARDSTEERING, BRAKE CONTROL

STEERING, BRAKE CONTROL

Regarding the transmission-related description of the operation of the PCCS lever, refer to the Transmission Control. PCCS: Palm Command Control System

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STRUCTURE, FUNCTION AND MAINTENANCE STANDARDSTEERING, BRAKE CONTROL

10-53D375A-51. Brake pedal2. Safety lever3. PCCS lever (Steering)4. Limit switch5. Steering controller6. Steering ECMV7. Brake valve8. Parking brake lever (From safety lever)9. Cable10. Rod (From brake pedal)11. Potentiometer

Positions of lever and pedal1: Neutral2: Forward straight-travel3: Reverse straight-travel4: Left clutch OFF5: Left clutch OFF Left brake ON6: Right clutch OFF7: Right clutch OFF Right brake ON8: Brake RELEASE9: Brake ON::FreeA: Lock

Outline The PCCS lever (3) sends an electric signal to the steering controller (10). After receiving it, the steering controller (10) sends a proportional current to the steering ECMV (6) to operate the steering clutch and brake. The brake pedal (1) sends an electric signal to the steering controller (10) via the potentiometer (11). After receiving it, the steering controller (10) sends a proportional current to the steering ECMV (6) to operate the brake. In this case, the right and left brakes operate at the same time to activate braking. The rod (5) operates the brake via the brake valve (9) for redundant use. (Only at the time of complete braking) If you slightly tilt the PCCS lever (3) leftward, the left steering clutch is partially disengaged, causing the machine to make a slow left swing.

If you completely tilt the PCCS lever (3) leftward, the left steering clutch is turned OFF completely and the left steering brake is turned ON, causing the machine to make a sudden left swing. The safety bar (2) is connected to the parking brake lever (8) and it also serves as a parking brake.

TRANSFER, BEVEL GEAR SHAFT, STEERING

1. Transmission unit2. Input shaft3. Steering unit4. Breather5. Parking brake valve6. Left brake ECMV7. Right brake ECMV8. Transmission output rotation sensor9. Filter10. Left clutch ECMV11. Right clutch ECMV12. Sudden braking prevention valve

STRUCTURE, FUNCTION AND MAINTENANCE STANDARDTRANSFER, BEVEL GEAR SHAFT, STEERING

10-55D375A-5STRUCTURE, FUNCTION ANDMAINTENANCE STANDARDTRANSFER, BEVEL GEAR SHAFT, STEERING

Transfer Bevel Gear Pinion

1. Input shaft2. Drive gear (35 teeth)3. Transmission output rotation sensor4. Rear cover5. Bearing gauge6. Driven gear (33 teeth)7. Bevel pinion (23 teeth)8. Bevel gear (40 teeth)

Outline The transfer bevel pinion is mounted at the rear part inside the steering case, which receives the power from the transmission output shaft by its input shaft (1). The transfer consists of the drive gear (2) and the driven gear (6) to reduce the power speed from the input shaft (1), transferring it to the bevel pinion (7). It is also provided with the transmission output rotation sensor (3) to send the pulse signal of the drive gear (2) to the torque converter lock-up controller using an electric signal.

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STRUCTURE, FUNCTION ANDMAINTENANCE STANDARDTRANSFER, BEVEL GEAR SHAFT, STEERING

Unit: mm

No.Check itemCriteriaRemedy

1Backlash of transfer gearStandard clearanceClearance limitAdjust or replace

0.24 0.630.75

2Thickness of collar between transfer gear and bearingStandard sizeRepair limitReplace

2423.6

3Standard shim thickness for bearing cage mount2.0Adjust

D375A-5 10-57


BEVEL GEAR SHAFT, STEERING CLUTCH, BRAKE

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1. Clutch cage2. Clutch housing3. Clutch spring4. Clutch piston5. Torque pin6. Clutch disc (One side: 9 sheets)7. Clutch plate (One side: 9 sheets)8. Spacer9. Clutch stopper10. Clutch hub11. Bearing cage12. Bevel gear (Number of teeth: 40)13. Bevel gear shaft14. Bevel gear shaft15. Bearing cage16. Pipe17. Brake stopper18. Brake hub19. Brake disc (One side: 9 sheets)20. Spacer21. Brake plate (One side: 9 sheets)22. Torque pin23. Brake piston24. Brake case25. Brake spring26. Brake cage27. Sleeve28. Output shaft

Outline As steering clutches, wet-type, multiple disc type, and spring-boosted types are adopted. If you operate the PCCS lever, the controller outputs a proportional solenoid current to hydrauli- ca ll y op er a t e t h e st ee r i n g E C M V w h i l e interlocking with the brake.As a lubrication method, forced lubrication is adopted, which makes oil from the power train oil cooler flow through the passage in the steering case to the housing and cage, and up to the disc plate. As steering brakes, wet-type, multiple disc type, and spring-boosted types brakes are adopted. If you operate the brake pedal and PCCS lever, the controller outputs a proportional solenoid current to hydraulically operate the steering valve ECMV while interlocking with the brake. As a lubrication method, forced lubrication is adopted, which makes oil from the power train oil cooler flow through the passage in the steering case to the housing and cage, and up to the disc plate.When the engine is stopping, the steering brake is ON since the back pressure of the brake piston lowers unless you press the brake pedal. Since the brake is released as the oil pressure in the circuit goes up when the engine restarts, the parking lock lever must be locked.

D375A-5 10-59


10-60D375A-5


Unit: mm


1Thickness of brake, clutch plateStandard sizeRepair limitReplace

2.92.5

Distortion of brake, clutch plateToleranceRepair limitRepair or replace

Less than 0.30.4

2Thickness of brake, clutch discStandard sizeRepair limitReplace

4.74.2

Distortion of brake, clutchToleranceRepair limitRepair or replace

Less than 0.30.4

3Overall assembled thickness of brake plates and discsStandard sizeRepair limit

Replace

68.464.7

4Overall assembled thickness of clutch plates and discs68.465.4

5Backlash between brake, clutch disc and brake hubStandard clearanceRepair limit

0.17 0.521.0

6Backlash between bevel gear and pinion0.3 0.40.75Adjust or replace

7Clearance between piston seal ring groove and seal ring0.5 0.80.8

Replace

8Clearance between cage seal ring groove and seal ring0.5 0.80.8

9

Inside diameter of cage seal ring contact surfaceStandard sizeToleranceStandard clearanceClearance limit

ShaftHole

2900.50.7+0.08100.5 0.781

10Inside diameter of piston seal ring contact surface2450.0500.122+0.04600.050 0.168

11

Brake belleville springStandard sizeRepair limit

Free lengthInstalled lengthInstalled loadFree lengthInstalled load

17.111.238.7 kN{3,950 kg}16.533.9 kN{3,460 kg}

12Clutch belleville spring17.611.3537.9 kN{3,860 kg}17.036.0 kN{3,670 kg}

13

Interference between bevel gear and reamer boltStandard sizeToleranceStandard interferenceInterference limit

ShaftHole

16+0.019+0.001+0.02700.026 0.0190.02

14Runout of back face of bevel gearRepair limit: 0.05 (measure after installing to bevel gear)Repair or replace

15Preload of bevel gear shaft taper roller bearingStandard rotating torque: 4.9 5.9 Nm {0.5 0.6 kgm} (At tip of bevel gear teeth with bevel pinion and gear not meshed: 23.5 28.4 N {2.4 2.9 kg})Adjust

16Standard shim thickness for bearing cage2.0Adjust shim

D375A-5 10-61

STRUCTURE, FUNCTION ANDMAINTENANCE STANDARDSTEERING ECMV

STEERING ECMV

(Electronic Control Modulation Valve)

10-62D375A-5


1. ECMV (For left clutch)2. ECMV (For right clutch)3. Sudden braking prevention valve4. Parking brake valve5. ECMV (For left brake)6. ECMV (For right brake)7. Filter8. Valve seatA. Left clutch operating pressure pick-up portB. Right clutch operating pressure pick-up portC. Left brake operating pressure pick-up portD. Right brake operating pressure pick-up portE. To left clutchF. To left lubricationG. To left brakeH. To right clutchJ. To right lubricationK. To right brakeL. Bevel gear shaft lubrication inletM. To pin puller solenoid valveN. From pin puller solenoid valveP. From pump

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Outline This machine employs four ECMV (electronic- controlled modulation valve) on the steering control valve. The steering control valve is provided on respective valve sheets as the assembly. The steering control valve is situated in the circuit between the power train pump via the main relief valve and the piston of the steering clutch and the brake. It is configured with two pairs of the steering ECMV (right and left) and the brake ECMV (right and left). Shifting the PCCS lever (steering and forward/ reverse) right or left disconnects the steering clutch. Shifting it further turns ON the brake. The controller sends the instruction to respective ECMV to cause the gradual or sudden turn whichever is designated by the operating position of the PCCS lever (steering lever). Depending on depth of the pedal depression, the controller instructs ECMV to apply the right and left brakes to stop the machine.The controller that is electrically connected to the PCCS lever and pedal performs above opera- tions by switching the steering control valves (each ECMV).The steering control valves feed the oil from the power train pump to the steering clutch and brake to operate their disk clutches. The sudden stop prevention valve disables sudden braking that can result when a failure is de- tected in the electric systems. Shifting the parking brake lever to the Lock position switches the port of the parking brake valve, thereby draining the oil between the ECMV for left-and-right brakes and the brake. As the result, the machine brake is turned on.The parking brake is also connected to the brake pedal via the linkage.

D375A-5 10-65

STRUCTURE, FUNCTION ANDMAINTENANCE STANDARDSTEERING CLUTCH, STEERING BRAKE ECMV

STEERING CLUTCH, STEERING BRAKE ECMV

(Electronic control modulating valve)

A: To clutch or brake P: From pumpT: Drain Dr: DrainP1: Clutch or brake pressure pick-up port P2: Pilot pressure pick-up port1. Fill switch connector2. Proportional solenoid connector3. Pressure detection valve4. Fill switch5. Proportional solenoid6. Pressure control valve

10-66 D375A-5


Outline of ECMV The ECMV (Electronic Control Modulating valve) consists of a pressure control valve and a fill switch. Pressure control valveThis valve allows a proportional solenoid to re- ceive a current sent from a steering controller and converts it to oil pressure. Fill switchThis component detects that a clutch is filled with oil and has the following functions.1) When the clutch is filled with the oil, at the same time, a signal (fill signal) is output to the controller and transmits filling termina- tion.2) While oil pressure is applied to the clutch, the signal (fill signal) is output to the controller and transmits the presence of oil pressure.

ECMV and Proportional Solenoid One proportional solenoid is mounted for each ECMV. A thrust is generated according to the command current of the controller.The thrust generated by the proportional solenoid is actuated on a pressure control valve spool and generates oil pressure. Accordingly, by controlling an amount of the command current, the thrust changes and the pressure control valve is actuated, then a flow of oil and the oil pressure is controlled.

Operation of ECMV The ECMV is controlled using the command current from the controller to the proportional solenoid and a fill switch output signal.

ECMV for Steering Clutch and Steering Brake

Outline This valve sets the steering clutch oil pressure or the steering brake oil pressure to a set pressure and switches a circuit to the clutch chamber and the brake chamber.

D375A-5 10-67


Operation

1. In case of PCCS lever Neutral, brake pedal Released: Straight travel(Left and right clutch ON, left and right brake Released, parking brake OFF)

In the position of PCCS lever Neutral and brake pedal Released, because the solenoid valve (1) of the steering ECMV is deenergized, the sealing portion of the ball (2) is opened.The oil from the power train pump enters the port Pc of the steering ECMV via the main relief valve. The oil that entered the port Pc passes through the orifice a and passes through the sealing portion of the ball (2), then is drained. The valve (3) is moved right by the tension of the spring (4) and closes the Pc and C ports, then opens the C and Dr ports. At this time, the oil from the back pressure port of a clutch piston is drained from the port C and the clutch is set to ON by the tension of the clutch spring. The oil pressure of the brake circuit is ensured by the orifice a. Further, the proportional solenoid valve (5) of the brake ECMV is energized and pushes the ball (6) to the left direction, then closes the sealing portion. The oil that entered the pump port Pb enters the E port, pushes the valve (7) left, opens the Pb and B ports, and closes the B and Dr ports. The oil that entered the Pb port passes through the B port and flows into the back pressure port of the brake piston. Subsequently, the piston moves to the left direction waiting for the rise of the circuit oil pressure and compresses the brake spring, then sets the brake Released. In the parking brake OFF, the parking brake is closed and the oil of the brake circuit is not drained.

10-68D375A-5


2. When the PCCS lever is actuated halfway to the left: Slow swing(Left clutch OFF, left brake Semi-released, right clutch ON, right brake Released, parking brake OFF)

When the PCCS lever is actuated halfway to the left, the solenoid valve (1) of the left steering ECMV is energized and pushes the ball (2) to the left direction, then closes the sealing portion. The oil from the power train pump passes through the orifice a from the port Pc and enters F. Subse- quently, the oil pushes the valve (3) to the left and opens the Pc and C ports, then closes the C and Dr ports. The oil of the C port flows into the clutch piston port and becomes the back pressure, then sets the left clutch to OFF. Further, the proportional solenoid valve (5) of the left ECMV is energized and pushes the ball (6) to the left direction, then closes the sealing portion. The oil that entered the pump port Pb enters the E port and pushes the valve (7) to the left.Besides, the oil pressure of the port B and later outputs a command current from the controller to the

proportional solenoid valve (5) in accordance with the stroke of the PCCS lever. When the current flows into the proportional solenoid (5), the solenoid generates a thrust in proportion to the current. The sum of the thrust of this solenoid, the thrust caused by the brake port oil pressure, and the res- titution of the pressure control valve spring (8) is balanced and pressure-adjusted. Accordingly, if the stroke of the PCCS lever is small, the oil pressure of the port B and later is also specified high and the brake changes from Re- leased to Semi-released. If the stroke is large, the oil pressure is specified low and the brake changes from Semi-released to ON. In the parking brake OFF, the parking brake valve is closed and the oil of the brake circuit is not drained.

D375A-5 10-69


3. When the PCCS lever is actuated fully to the left: Sudden swing(Left clutch OFF, left brake ON, right clutch ON, right brake Released, parking brake OFF)

When the PCCS lever is actuated fully to the left from the state of Section 2, the proportional solenoid valve (5) of the left brake ECMV is deenergized and sets the ball (6) free, then opens the sealing portion.Because the oil of the port E passes through the sealing portion and is drained, the valve (7) is moved right by the tension of the spring (8).At this time, the port Pb closes and the port Band drain port Dr open. The oil from the power train pump passes through the orifice b from the port Pb and passes through the sealing portion, then is drained. The oil pressure of the clutch circuit is ensured by the orifice b. On the other hand, the oil that flows into the brake piston port and reached the back pressure is drained from the port B to Dr.

The left brake is set to ON by the tension of the brake spring. In the parking brake OFF, the parking brake valve is closed and the oil of the brake circuit is not drained.

10-70D375A-5


4. In case of brake pedal Stepped on(Clutch ON, brake ON, parking brake OFF)

When the brake pedal is stepped on, the proportional solenoid valve (5) of the left and right brake ECMVs is deenergized from energization by the pedal full actuation. A command current is output from the controller to the proportional solenoid valve (5) in accordance with the actuation stroke of the brake pedal. When the current flows into the proportional solenoid valve (5), the solenoid generates a thrust that is proportional to the current. The sum of the thrust of this solenoid, the thrust caused by the oil pressure of the brake port, and the resti- tution of the pressure control valve spring (8) is balanced and oil pressure is specified, thereby enabling adjustment of the effect of the brake. Besides, because the PCCS lever is not actuated, the solenoid valve (1) of the left and right

steering ECMVs is deenergized and the left and right clutches are set to ON. Further, when the brake pedal is stepped on, the parking brake valve linked using a linkage is actuated and drains the oil of the brake circuit.

D375A-5 10-71


5. In case of parking brake ON(Clutch ON, brake ON, PCCS lever Neutral, braking pedal Released)

When the safety lever for the PCCS lever is set to the position of Locked, the parking brake valve (1) moves to the left direction and the ports A, B, and C open. Accordingly, the oil that flows into the brake piston port and reached the back pressure passes through the port C from the ports A and B and is drained. The back pressure of the brake piston port continues decreasing and the brake is fully set to ON, then is held in the state. Further, because the ports A and B continue be- ing opened together with the drain port C even if the engine is restarted, the state of the brake ON is held. In the parking brake OFF, the parking brake valve (1) moves right and is closed between the

port A, port B, and drain port C, then the brake is set Released by oil pressure.

10-72D375A-5

STRUCTURE, FUNCTION ANDMAINTENANCE STANDARDPARKING BRAKE VALVE

PARKING BRAKE VALVE

Unit: mm


1

Clearance between parking brake valve spool and valve bodyStandard sizeToleranceStandard clearanceClearance limit

Replace

ShaftHole

140.0200.030+0.01100.020 0.0410.05

2Sliding portion outside diameter (spool) with dust sealing and V- packing

14ToleranceRepair limitHard chrome plating correction and replace

0.0200.03013.9

3

Parking brake valve spool springStandard sizeRepair limit

Replace

Free lengthInstalled lengthInstalled loadFree lengthInstalled load

6547.738.2 N{3.9 kg}63.136.3 N{3.71 kg}

D375A-5 10-73

STRUCTURE, FUNCTION ANDMAINTENANCE STANDARDSTEERING ELECTRONIC CONTROL

STEERING ELECTRONIC CONTROL

1. Monitor panel (Speed range display)2. Auto shift down switch3. Engine controller4. Transmission controller5. Steering controller6. Steering control valve7. Transmission output shaft speed sensor8. Transmission control valve9. Engine speed sensor

10-202D375A-5

STRUCTURE, FUNCTION ANDMAINTENANCE STANDARDSTEERING ELECTRONIC CONTROL

Shift Mode Function1. FunctionIf you shift the lever to the forward or reverse, the gear speed selected from the shift mode is turned on.

2. Type of Modes1) F1-R1 (Manual mode)2) F1-R2 (Shift mode 1)3) F2-R2 (Shift mode 2)

3. Selecting methodShift the PCCS lever to "N".Select the shift mode using UP or DOWN switch.

Up switch ONUp switch ON

Manual modeShift mode 1Shift mode 2

Down switch ON

Down switch ON

4. DisplayThe selected shift mode is displayed on the monitor panel.

Auto-shift-down function1. FunctionIf the load is increased while the machine is traveling or working at the 2nd or 3rd gear speed, the gear speed is shifted down automatically.1) The drawbar pull (load on the machine) is calculated from the engine speed, travel speed, and throttle information from the steering controller, and the gear speed is shifted down automatically according to the load and travel speed.2) Once the gear speed is automatically shifted down, it is not automatically shifted up to the former position. (Gear speed can be shifted up with the manual switch.)3) This function is applicable to both forward and reverse travels.

2. How to useTurn the auto-shift-down switch (1) ON.

D375A-5 10-203

komatsu d375.docx

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