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Shop manual máy xúc lất HuynDai HL760 (Phần cơ cấu công tác) - Sơ đồ thủy lực - Kết cấu - Kiểm tra và hiệu chỉnh
SECTION 6 WORK EQUIPMENTSECTION 6 WORK EQUIPMENTGroup 1 Structure and Function ----------------------------------------------------------------------------------- 6-1Group 2 Operational Checks and Troubleshooting ----------------------------------------------------- 6-42Group 3 Tests and Adjustments ----------------------------------------------------------------------------------- 6-53Group 4 Disassembly and Assembly --------------------------------------------------------------------------- 6-68 6-11. HYDRAULIC SYSTEM OUTLINE1. HYDRAULIC SYSTEM OUTLINEThe loader hydraulic system is a pilot operated, closed center system which is supplied with flow from the variable displacement piston main hydraulic pump.The loader system components are :·Main pump·Main control valve·Bucket cylinder·Boom cylinders·Remote control valve (Pilot control valve)·Safety valveFlow from the main hydraulic pump not used by the steering system leaves the steering valve (EHPS) EF port.It flows to the inlet port plate of two section or three section block type main control valve.The main control valve is load pressure independent flow distribution system which routes flow to the boom, bucket or auxiliary cylinders (not shown) when the respective spools are shifted.Flow from the main pump is routed to the main control valve where pump outlet pressure is reduced to pilot circuit pressure. The main control valve flow to the remote control valve.The remote control valve routed flow to either end of each spool valve section in the main control valve to control spool stroke.A accumulator mounted on safety valve supplies a secondary pressure source to operated remote control valve so the boom can be lowered if the engine is off.The return circuit for the main hydraulic system have return filter inside the hydraulic tank. The return filter uses a filter element and a bypass valve. The bypass valve is located in the upside of filter.SECTION 6 WORK EQUIPMENTSECTION 6 WORK EQUIPMENT GROUP 1 STRUCTURE AND FUNCTIONGROUP 1 STRUCTURE AND FUNCTION 6-22. HYDRAULIC CIRCUIT2. HYDRAULIC CIRCUITPS31333257'142221232426227301818161716152035361911110438376893925342828FRONTREARRHLHMXBTX1AE/GE/GPARKINGCLCRLEFRPLSTPsTsELECTRONICS1 32 4ABDRABDRPTLRSPP1MTMB2L3L4B1L1L2S1S2X1X2X1 X2X3S1B1A1B2A2A3T1TPPS1BPSTPLMPTABP1T1P2T2A1A2B.D/FB.UCRAWDDUMP1342PT1.12.1PSTA1P1123T/MPS29PSAXLE13TP A112RHLHB1a1a2A2 B2pstLSa3B3A3S1S2b3B2A2b2292912b1PSPSDumpRoll backUpDownFloatingBucketBoomAux37 1 Main pump 2 Fan & brake pump 3 Main control valve 4 Remote control valve 5 Steering unit 6 Cushion valve 7 Steering valve (EHPS) 7' Electric steering valve (opt) 8 Controller (opt) 9 Joystick (opt) 10 Safety valve 11 Shuttle valve 12 Boom cylinder 13 Bucket cylinder 14 Steering cylinder 15 Cut-off valve 16 Accumulator 17 Accumulator 18 Pressure sensor 19 Brake valve 20 Pressure switch 21 Hydraulic tank 22 Air breather 23 Return filter 24 By pass valve 25 Strainer 26 Oil cooler 27 Pressure filter 28 Check valve 29 Pressure sensor 30 Fan motor 31 Pump motor (opt) 32 Check block (opt) 33 Pressure sensor (opt) 34 Check valve (opt) 35 Ride control valve (opt) 36 Accumulator (opt) 37 Quick coupler cylinder (opt) 38 Solenoid valve (opt) 39 Stop valve (opt)76096WE01 6-33. WORK EQUIPMENT HYDRAULIC CIRCUIT3. WORK EQUIPMENT HYDRAULIC CIRCUIT22212324111104252828E/GB2L3L4B1L1L2S1S2X1X2X1 X2X3S1B.D/FB.UCRAWDDUMP1342PT1.12.1TA1P1123PS13TP A112RHLHB1a1a2A2 B2pstLSa3B3A3S1S2b3B2A2b22912b1PSDumpRoll backUpDownFloatingBucketBoomAuxReturn lineFan & brake pumpSteering systemReturn lineSteering valve(EHPS) EF portSteering valve(EHPS) LS port3PS29 1 Main pump 3 Main control valve 4 Remote control valve 10 Safety valve 11 Shuttle valve 12 Boom cylinder 13 Bucket cylinder 21 Hydraulic tank 22 Air breather 23 Return filter 24 Bypass valve 25 Strainer 28 Check valve 29 Pressure sensor76096WE02 6-4WHEN THE RCV LEVER IS IN THE RAISE POSITIONWHEN THE RCV LEVER IS IN THE RAISE POSITIONWhen the RCV lever (4) is pulled back, the boom spool is moved to raise position by pilot oil pressure from port 3 of RCV.The oil from main pump (1) flows into main control valve (3) and then goes to the large chamber of boom cylinder (12).The oil from the small chamber of boom cylinder (12) returns to hydraulic oil tank (21) through the boom spool at the same time.When this happens, the boom goes up.····22212324111104252828E/GB2L3L4B1L1L2S1S2X1X2X1 X2X3S1B.D/FB.UCRAWDDUMP1342PT1.12.1TA1P1123PS13TP A112RHLHB1a1a2A2 B2pstLSa3B3A3S1S2b3B2A2b22912b1PSDumpRoll backUpDownFloatingBucketBoomAuxReturn lineFan & brake pumpSteering systemReturn lineSteering valve(EHPS) EF portSteering valve(EHPS) LS port3PS291)1)76096WE03 6-5WHEN THE RCV LEVER IS IN THE LOWER POSITIONWHEN THE RCV LEVER IS IN THE LOWER POSITIONWhen the RCV lever (4) is pushed forward, the boom spool is moved to lower position by pilot pressure.The oil from main pump (1) flows into main control valve (3) and then goes to small chamber of boom cylinder (12).The oil returned from large chamber of boom cylinder (12) returns to hydraulic tank (21) through the boom spool at the same time.When the lowering speed of boom is faster, the return oil from the large chamber of boom cylinder combines with the oil from the pump through the regeneration check valve, and flows into the small chamber of the cylinder.This prevents cylinder cavitation by the negative pressure when the pump flow cannot match the boom down speed.· ···22212324111104252828E/GB2L3L4B1L1L2S1S2X1X2X1 X2X3S1B.D/FB.UCRAWDDUMP1342PT1.12.1TA1P1123PS13TP A112RHLHB1a1a2A2 B2pstLSa3B3A3S1S2b3B2A2b22912b1PSDumpRoll backUpDownFloatingBucketBoomAuxReturn lineFan & brake pumpSteering systemReturn lineSteering valve(EHPS) EF portSteering valve(EHPS) LS port3Regenerationcheck valvePS292)2)76096WE04 6-6WHEN THE RCV LEVER IS IN THE FLOAT POSITIONWHEN THE RCV LEVER IS IN THE FLOAT POSITIONWhen the RCV lever (4) is pushed further forward from the lower position, the pilot pressure reaches to 13~15bar, then the boom spool is moved to floating position.The work ports (A2), (B2) and the small chamber and the large chamber are connected to the return passage, so the boom will be lowered due to it's own weight.In this condition, when the bucket is in contact with the ground, it can be move up and down in accordance with the shape of the ground.···22212324111104252828E/GB2L3L4B1L1L2S1S2X1X2X1 X2X3S1B.D/FB.UCRAWDDUMP1342PT1.12.1TA1P1123PS13TP A112RHLHB1a1a2A2 B2pstLSa3B3A3S1S2b3B2A2b22912b1PSDumpRoll backUpDownFloatingBucketBoomAuxReturn lineFan & brake pumpSteering systemReturn lineSteering valve(EHPS) EF portSteering valve(EHPS) LS port3PS293)3)76096WE05 6-7WHEN THE RCV LEVER IS IN THE DUMP POSITIONWHEN THE RCV LEVER IS IN THE DUMP POSITIONIf the RCV lever (4) is pushed right, the bucket spool is moved to dump position by pilot oil pressure from port 2 of RCV.The oil from main pump (1) flows into main control valve (3) and then goes to the small chamber of bucket cylinder (13).The oil at the large chamber of bucket cylinder (13) returns to hydraulic tank (21).When this happens, the bucket is dumped.When the dumping speed of bucket is faster, the oil returned from the large chamber of bucket cylinder combines with the oil from the pump, and flows into the small chamber of the cylinder.This prevents cylinder cavitation by the negative pressure when the pump flow cannot match the bucket dump speed.·····22212324111104252828E/GB2L3L4B1L1L2S1S2X1X2X1 X2X3S1B.D/FB.UCRAWDDUMP1342PT1.12.1TA1P1123PS13TP A112RHLHB1a1a2A2 B2pstLSa3B3A3S1S2b3B2A2b22912b1PSDumpRoll backUpDownFloatingBucketBoomAuxReturn lineFan & brake pumpSteering systemReturn lineSteering valve(EHPS) EF portSteering valve(EHPS) LS port3PS29Regenerationcheck valve4)4)76096WE06 6-8WHEN THE RCV LEVER IS IN THE ROLL BACK WHEN THE RCV LEVER IS IN THE ROLL BACK (retract) POSITION POSITIONIf the RCV lever (4) is pulled left, the bucket spool is moved to roll back position by pilot oil pressure from port 4 of RCV.The oil from main pump (1) flows into main control valve (3) and then goes to the large chamber of bucket cylinder.The oil at the chamber of bucket cylinder (13) returns to hydraulic tank (21). When this happens, the bucket roll back.····22212324111104252828E/GB2L3L4B1L1L2S1S2X1X2X1 X2X3S1B.D/FB.UCRAWDDUMP1342PT1.12.1TA1P1123PS13TP A112RHLHB1a1a2A2 B2pstLSa3B3A3S1S2b3B2A2b22912b1PSDumpRoll backUpDownFloatingBucketBoomAuxReturn lineFan & brake pumpSteering systemReturn lineSteering valve(EHPS) EF portSteering valve(EHPS) LS port3PS295)5)76096WE07 6-93. MAIN PUMP 3. MAIN PUMP STRUCTURE STRUCTURE (1/2)This variable displacement piston pump consists of steering pump and loader pump.1)1)L1L2B1X1 L3 B2X2S1 L4 S2E/GB2L3L4B1L1L2S1S2X1X2Hydraulic circuit76096WE88Port Port name Port sizeB1 Pressure port SAE 1"B2 Pressure port SAE 1"S1 Suction port SAE 2"S2 Suction port SAE 2"L1, L2 Case drain port 1 1/16-12UN-2BL3, L4 Case drain port 1 1/16-12UN-2BX1, X2 Pilot pressure port 7/16-20UNF-2B [...]... Bucket pilot port 11/1 6-1 6UN a2, b2 Boom pilot port 11/1 6-1 6UN a3, b3 Auxiliary pilot port 11/1 6-1 6UN LS Load sensing port 9/1 6-1 8UNF Pst To RCV P port 9/1 6-1 8UNF 6-2 3 STRUCTURE (2/3) 61 62 60 36 38 38 37 79 35 50 79 74 33 31 32 33 79 30 86 102 71 84 74 11 79 85 165 76096WE13 11 30 31 32 33 35 36 Housing O-ring O-ring O-ring O-ring O-ring O-ring 37 38 50 60 61 62 71 O-ring O-ring Housing Plate Cylinder... 6,31 37 2 33 12 51 53 52 16 1-2 54 30 1-1 7 17 22 5 8 25 1 1-1 1-2 2 5 6 7 8 10 15 20 Rotary group High speed rotary group Control plate Adjusting piece Pump housing Port plate Swash plate Drive shaft Splined hub 76096WE11 12 15 16 17 20 22 23 24 25 Adjustment shim Taper roller bearing Taper roller bearing Bearing liner Shaft seal ring O-ring O-ring O-ring Retaining ring 6-1 0 27 30 31 33 37 51 52 53... Gauge A - Gauge B ·Specification : Steering pump (25 bar) / Loader pump (20 bar) Gauge B Flow compensator X 2 1 Gauge A -1 6 bar/rev B +16 bar/rev L1 L S 75796WE37 (6) Adjustment of pressure control Pressure compensator setting must be carried out following procedures and conditions ① Conditions - Engine is running - System is at relief condition ② Procedures - Loosening the hexagon nut (2) - Adjusting... return to low pressure standby 6-1 8 (5) Adjustment of flow control Flow compensator setting must be carried out following procedures and conditions ① Conditions - Engine is running (at high or low idle) - RCV is operated slowly (example : Boom up) - Pressure gauges are installed ※ Discharge pump flow should be less than max pump flow ② Procedures - Loosening the hexagon nut (2) - Adjusting screw (1) of flow... O-ring O-ring Retaining ring 6-1 0 27 30 31 33 37 51 52 53 54 Socket screw Locking screw Double break-off pin Cylinder pin Side mark ring Control valve Gasket Socket head screw Locking screw · MAIN PUMP (2/2, LOADER) 28 27 23 6,31 2 2 33 41 43 42 16 12 11 1-2 44 1-1 30 7 22 17 5 8 20 25 15 76096WE12 1 1-1 1-2 2 5 6 7 8 11 Rotary group High speed rotary group Control plate Adjusting piece Pump housing Port... left until cross-drilled hole (24) allows the oil to drain to the case 6-1 6 Cross-drilled hole (24) limits the maximum travel of control piston (10) to the left The pump supplies a sufficient amount of flow that compensates for system leakage The pump also supplies a sufficient of flow that compensates for leakage to the pump case The leakage to the pump case is a result of the cross-drilled hole The... energized, then control lever (1) is held in its end position by magnetic force This lock is released automatically when the solenoid is deenergized 6-2 2 5 MAIN CONTROL VALVE 1) STRUCTURE (1/3) ·Type : Closed center, Load pressure - Independent - Flow - Distribution b3 a3 A3 B3 LS pst b2 a2 A2 B2 A1 B1 b1 a1 P T a2 a1 Roll back a3 A2 B2 pst A3 B3 Down Floating A1 B1 Bucket Up P Dump T LS Aux Boom S1... plate Drive shaft Adjustment shim 12 15 16 17 20 22 23 25 27 Adjustment shim Taper roller bearing Taper roller bearing Bearing liner Shaft seal ring O-ring O-ring Retaining ring Socket screw 6-1 1 28 30 31 33 41 42 43 44 Locking screw Locking screw Double break-off pin Cylinder pin Control valve Gasket Socket screw Locking screw 2) FUNCTION 1 2 3 4 5 6 LS pressure 12 13 X 11 8 9 L B L1 10 S 7 X 13 12 4 10... fitting O-ring O-ring Spool Spool 6-2 5 50 90 91 95 96 Housing Compression spring Spring retainer Spring retainer Spring retainer 2) FUNCTION 4 6 B A P T a b A 2 B 3 5 1 3 a2 a1 A2 B2 pst A1 B1 Bucket Up Roll back LS Down Floating P Dump T 7 Boom A2 b1 4 5 B2 6 b2 Hydraulic circuit 76096WE15 1 2 3 Housing Spool Pressure compensator 4 5 6 Counter balance valve Regeneration check valve Port relief valve 6-2 6... anti-cavitation functions protect the actuators from overloads and cavitation (5) Float position The float position is obtained by means of a 4-position spool (6) (6 Regeneration To prevent cavitation, with negative loads (e g dump or lowering), the tank port is pre-loaded via counter balance valve (4) and is fed with oil via the regeneration check valve (5) downstream of the pressure compensator 6-2 7 . -- -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - 6-4 2Group 3 Tests and Adjustments -- -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - . -- -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - 6-1 Group 2 Operational Checks and Troubleshooting -- -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- - -- -