00-1

SEBM038800

© 2005 All Rights ReservedPrinted in Japan 03-05 (01)

MACHINE MODEL SERIAL No.

D155AX-5 76001 and up

• This manual contains only information related to the KOMATSU-iBlade Specification.For other information, see the D155AX-5 Shop Manual SEBM034806.

• This shop manual may contain attachments and optional equipment that are not availablein your area.Please consult your local Komatsu distributor for those items you may require.Materials and specifications are subject to change without notice.

• D155AX-5 mounts the SA6D140E-3 engine.For details of the engine, see the 140-3 Series Engine Shop Manual.

KOMATSU-iBLADE Specification

00-2 D155AX-5

GENERAL

CONTENTS

No. of page

01 GENERAL............................................................................................................................ 01-1

10 STRUCTURE, FUNCTION AND MAINTENANCE STANDARD............................................ 10-1

30 DISASSEMBLY AND ASSEMBLY ..................................................... 30-1

90 OTHERS ................................................................................................................................ 90-1

D155AX-5 01-1

SPECIFICATION DRAWING ........................................................................................................................01- 2

01 GENERAL

01-2 D155AX-5

GENERAL SPECIFICATION DRAWING

SPECIFICATION DRAWING

Item Unit Full U-tilt dozer + Giant ripper

U-tilt dozer + Giant ripper

Semi U-tilt dozer + Multi-shank ripper

Full U-tilt dozer + Multi-shank ripper

A Overall length mm 8,550 8,155 8,155 8,550

B Overall height mm 4,195 4,195 4,195 4,195

C Overall width mm 4,265 3,955 3,955 4,265

D155AX-5 10-1

WORK EQUIPMENT CONTROL..................................................................................................................10- 2PPC VALVE...................................................................................................................................................10- 4

10 STRUCTURE, FUNCTION AND MAINTENANCE STANDARD

10-2 D155AX-5

STRUCTURE, FUNCTION AND MAINTENANCE STANDARD WORK EQUIPMENT CONTROL

WORK EQUIPMENT CONTROL• The drawing shows a pitch dozer and pin puller installed vehicle.

D155AX-5 10-3

STRUCTURE, FUNCTION AND MAINTENANCE STANDARD WORK EQUIPMENT CONTROL

1. Work equipment lock lever2. Blade control lever3. Blade automatic control ON/OFF selector switch4. PPC lock valve

Lever positionsA. Blade HOLDB. Blade LOWERC. Blade FLOATD. Blade RAISEE. Blade (left tilt)F. Blade (right tilt)M. FREEN. LOCKO. Blade automatic control selector switch OFFP. Blade automatic control selector switch ON

Outline• The work equipment control employs a PPC sys-

tem which uses a PPC valve to move the spoolsof the control valve.

• Work equipment lock lever (1) is interconnectedwith PPC lock valve (4), and when it is at theLOCK position, the flow of oil in the PPC circuit isstopped.

10-4 D155AX-5

STRUCTURE, FUNCTION AND MAINTENANCE STANDARD PPC VALVE

PPC VALVEFor blade lift and tilt

1. PPC valve2. Shuttle valve3. EPC valve

PPPC : From manual/auto selector valve port B1 (via PPC lock valve)

T : To hydraulic tankPEPC : From manual/auto selector valve port P1PC1 : To blade lift valve (LOWER) port P3

(via junction block B2)PC2 : To blade lift valve (RAISE) port P4PC3 : To blade lift valve (LEFT TILT) port PA1PC4 : To blade lift valve (RIGHT TILT) port PB1

D155AX-5 10-5

STRUCTURE, FUNCTION AND MAINTENANCE STANDARD PPC VALVE

Function• The EPC solenoid valve consists of the propor-

tional solenoid valve portion and the oil pressureblock.

• From the control box (TOPCON), an electric sig-nal is sent to the EPC valve according to theamount that right control lever is moved.

• When signal current i is received from the controlbox, an EPC output is generated in proportion tothe level of the current to drive the work equip-ment valve.The shuttle valve supplies the higher output ofthe PPC valve and EPC valve to the work equip-ment valve to drive the spool.

Operation1. When signal current is 0 (coil deenergized)• When there is no signal current flowing from the

controller to coil (9), coil (9) is deenergized.• For this reason, spool (6) is pushed to the right in

the direction of the arrow by spring (7).• As a result, port P is closed, and the pressurized

oil passing through the PPC and EPC chargevalve from the charge pump does not flow to thecontrol valve.At the same time, pressurized oil from the controlvalve flows from port C through port T and isdrained to the tank.

10-6 D155AX-5

STRUCTURE, FUNCTION AND MAINTENANCE STANDARD PPC VALVE

2. When signal current is small (coil excited,during fine control )

• When a small signal current flows to coil (9), coil(9) is excited and a propulsion force pushing tothe left in the direction of the arrow is generatedin plunger (10).

• Push pin (8) pushes spool (6) to the left in the di-rection of the arrow and pressurized oil flowsfrom port P to port C.

• The pressure at port C rises and the force actingon face a of spool (6) + the spring load of spring(7) becomes greater than the propulsion force ofplunger (10). When this happens, spool (6) ispushed to the right, port P and port C are shut off,and at the same time, port C and port T are con-nected.

• As a result, spool (6) moves to the left or right toa position where the propulsion force of plunger(10) is balanced with the pressure at port C + thespring force of spring (7).

• Therefore, the circuit pressure between the EPCvalve and the control valve is controlled in pro-portion to the size of the signal current.

3. When signal current is large (coil is excited,full power control)

• When signal current flows to coil (9), coil (9) isexcited.

• The signal current at this point is the maximum,so the propulsion force of plunger (10) is also themaximum.

• Because of this, spool (6) is pushed to the left inthe direction of the arrow by push pin (8).

• As a result, the maximum flow of pressurized oilfrom port P flows to port C and the circuit pres-sure between the EPC valve and the controlvalve becomes the maximum.At the same time, port T is closed and no oil flowsto the tank.

D155AX-5 30-1

REMOVAL AND INSTALLATION OF ROPS GUARD.................................................................................30-2

30 DISASSEMBLY AND ASSEMBLY

30-2 D155AX-5

DISASSEMBLY AND ASSEMBLY REMOVAL AND INSTALLATION OF ROPS GUARD

REMOVAL AND INSTALLATION OF ROPS GUARDRemoval1. Remove clip (1) (installed in the operator's cab).2. Pull antenna cable (2) out of hole h1.3. Disconnect connector CN-GP9 at position P.4. Remove clips (3).5. Pull the antenna cable and rotary lamp wiring

harness (4) out of hole h2.6. Remove the ROPS according to the Shop man-

ual for the standard model.

Installation • Carry out installation in the reverse order to

removal.

D155AX-5 90-1

HYDRAULIC CIRCUIT DIAGRAM (FOR iBLADE SPECIFICATION)........................................................... 90- 3EELECTRICAL CIRCUIT DIAGRAM (FOR iBLADE SPECIFICATION) ....................................................... 90- 5

90 OTHERS

D155AX-5 90-3

OTHERS HYDRAULIC CIRCUIT DIAGRAM (FOR iBLADE SPECIFICATION)

HYDRAULIC CIRCUIT DIAGRAM (FOR iBLADE SPECIFICATION)

D155AX-5 90-5

OTHERS ELECTRICAL CIRCUIT DIAGRAM (FOR iBLADE SPECIFICATION)

ELECTRICAL CIRCUIT DIAGRAM (FOR iBLADE SPECIFICATION)