Shop manual máy đào HuynDai R250: An toan, cấu trúc, sơ đồ điện, thủy lực,
2-471. STRUCTURESwing device consists swing motor, swing reduction gear.Swing motor include mechanical parking valve, relief valve, make up valve and time delay valve.GROUP 3 SWING DEVICEAVIEW ABAPgShDr(dr4)MuRelief valveTime delay valveSwing motorReduction gearR/G Air bleed port(AGr, PT 1/4)R/G drain port(Dr, PT 3/8)R/G grease fill port(SGr, PT 1/8)Air bleed port(Au, PF 1/4)GBGAPortA, BDr2MuGA, GBPgShPort nameMain portDrain portMake up portGauge portBrake release portBrake pilot portPort sizeØ19PF 3/8PF 1PF 1/4PF 1/4PF 1/425072SM01GBShPgDr(dr4)GAABMuAu25072SM02 2-48SWING MOTOR1 Iner ring2 Oil seal 3 Taper roller bearing5 Backing spring6 Cam plate7 Return plate8 Piston assembly9 Lining plate10 Plate11 O-ring12 Piston13 O-ring14 Spring15 Parallel pin16 Piston17 O-ring18 Cap19 Scrowave20 Teflon ring21 Bushing22 Balance plate23 Needle bearing24 Snap ring25 Cylinder26 Housing27 Collar28 Plug29 Snap ring30 Bypass valve assembly31 Back up ring32 O-ring33 O-ring34 Cover35 Time delay valve36 Hexagon socket bolt37 O-ring38 O-ring39 Reliet valve assy40 O-ring41 Hexagon socket bolt42 Check43 Spring44 Cap45 Back up ring1)25072SM03 2-49REDUCTION GEAR1 Casing2 Drive shaft3 Spacer4 Roller bearing5 Cover plate6 Hexagon bolt7 Oil seal8 Roller bearing9 Carrier 210 Sun gear 211 Planet gear 212 Pin 213 bushing 214 Spring pin15 Thrust washer16 Carrier 117 Sun gear 118 Planet gear 119 Pin 120 Needle cage21 Side plate 122 Ring gear23 Knock pin24 Socket bolt25 Pinion gear26 Lock plate27 Lock washer28 Hexagon bolt29 Plug30 Plug31 Side plate 232 Stop ring33 Spring pin34 Spring pin35 Gage bar36 Gage pipe2418(B)2930910223321 192036 35313217325262716347814152311 121314562822)25072SM04 2-502. FUNCTIONROTARY PARTWhen high pressurized oil enters a cylinder through port(a), which is the inlet of balance plate(1),hydraulic pressure acting on the piston causes axial force F. The pressure force F works via thepiston(2) upon the return plate(3) which acts upon the swash plate(4) via an hydrostatic bearing.Force F1 perpendicular to swash plate(4) and force F2 perpendicular to cylinder center.Being transferred to the cylinder block(5) through piston, force F2 causes rotational moment atsurroundings of cylinder.Since cylinder block has 9 equidistantly arrayed pistons, rotational torque is transmitted to cylindershaft in order by several pistons connected to the inlet port of high pressurized oil. When thedirection of oil flow is reversed, rotational direction of cylinder is also reversed. Output torque isgiven by the equation.p×qFT = , q=Z・A・PCD・tanθ, F1 = , F2=F tanθ, S=PCD×tanθ2ЛCOSθWhere p : Effective difference of pressure(kgf/cm2)q : Displacement(cc/rev)T : Output torque(kgf・cm)Z : Piston number(9EA)A : Piston area(cm2)θ: Tilting angle of swash plate(degree)S : Piston stroke(cm)1)4 3 2 5 1FaHighpressure oilaHighpressure oilLowpressure oilF2PCDS25072SM05 AB2-51MAKE UP VALVEIn the system using this type of motor, there is no counter balance functioning valve and therehappens the case of revolution exceeding hydraulic supply of motor. To prevent the cavitationcaused by insufficient oil flow there is a make up valve to fill up the oil insufficiency.A make up valve is provided immediately before the port leading to the hydraulic oil tank to securefeed pressure required when the hydraulic motor makes a pumping action. The boost pressureacts on the hydraulic motor's feed port via the make up valve.Pressurized oil into the port B, the motor rotate counterclockwise.If the plunger of MCV moves neutral position, the oil in the motor is drain via left relief valve, thedrain oil run into motor via right make up valve, which prevent the cavitation of motor.2)210LC-7(2-47) 2-521 Body2 Seat3 Plunger4 Spring5 Adjusting screw6 Piston7 Bushing8 Spring seat9 Shim10 O-ring11 Back up ring12 O-ringConstruction of relief valveThe valve casing contains two cartridge type relief valves that stop the regular and reverserotations of the hydraulic motor. The relief valves relieve high pressure at start or at stop of swingmotion and can control the relief pressure in two steps, high and low, in order to insure smoothoperation.Function of relief valve Figure illustrates how the pressure actingon the relief valve is related to its risingprocess. Here is given the function,referring to the figure following page.569311107812142RELIEF VALVE3)(1)(2)(210LC-7) 2-48(1)P=pressure, T=timePPSP1P21234T(360LC-7) 2-51(1) 2-53Ports (P,R) at tank pressure.When hydraulic oil pressure(P×A1) reaches the preset force(FSP) of spring(4), the plunger(3)moves to the right as shown.P1×A1=Fsp+Pg×A2PA1RA2mhn g4gP=P1P1=Fsp+Pg×A2A1①②210LC-7(2-49)210LC-7(2-49) 2-54The oil flow chamber g via orifice m and n. When the pressure of chamber g reaches the presetforce(FSP) of spring(4), the piston(6) moves left and stop the piston(6) hits the bottom of bushing(7). When piston(6) hits the bottom of bushing(7), it stops moving to the left any further. As theresult, the pressure in chamber(g) equals(Ps).Ps×A1=Fsp+Ps×A2Ps=Fsp A1-A2 64mng76gP=P2P=Ps③④(210LC-7) 4-29(210LC-7) 4-49 2-55BRAKE SYSTEMControl valve swing brake systemThis is the brake system to stop the swing motion of the excavator during operation.In this system, the hydraulic circuit is throttled by the swing control valve, and the resistancecreated by this throttling works as a brake force to slow down the swing motion.Mechanical swing parking brake systemThe mechanical swing parking brake system is installed to prevent the upper structure fromswinging downhill because of its own weight when the excavator is parked on a slope since itcompletely eliminates the hydraulic drift of swing motion while the excavator is on a slop, work canbe done more easily and safely.Brake assemblyCircumferential rotation of separateplate(9) is constrained by the groovelocated at housing(26). When housingis pressed down by brake spring(16)through lining plate(10), separateplate(9) and brake piston(12), frictionforce occurs there.Cylinder(25) is constrained by this frictionforce and brake acts, while brakereleases when hydraulic force exceedsspring force.WorkDeceleration StopMCV A, B opened MCV A, B throttled MCV A, B closedMCV MCV MCV ABABAB4)(1)(2)①①(210LC-7) 2-48(1)9 Separate plate10 Lining plate12 Brake piston14 Spring25 Cylinder26 Housing45070SM05 2-56Operating principleWhen the swing control lever(1) is set to the swing position, the pilot oil go to the swing controlvalve(2) and to Shof the time delay valve(3) via the shuttle valve(4), this pressure movespool(5) to the leftward against the force of the spring(8), so pilot pump charged oil(P3) goes tothe chamber G.This pressure is applied to move the piston(6) to the upward against the force of the spring(9).Thus, it releases the brake force.10D1169G8537PgSh122421P3②②a.25072SM061 Swing control lever2 Swing control valve(MCV)3 Time delay valve4 Shuttle valve5 Spool6 Piston7 Poppet8 Spring9 Spring10 Orifice11 Spring12 Pilot pump [...]... Front cover Plunger Spring Socket bolt Snap ring Snap ring Snap ring Snap ring Roller bearing Roller bearing Spring pin Plug Plug Plug O-ring O-ring 2-5 7-2 485 487 488 491 702 706 707 712 742 743 744 745 746 747 748 993 994 O-ring O-ring O-ring Oil seal Piston O-ring O-ring Brake spring Friction plate Separate plate Dust plug Dust plug Dust plug Name plate Rivet screw Level gauge Plug 2) REDUCTION GEAR... PF1/4 A PG Brake release port PF1/4 SH PA Brake pilot port PF1/4 B 2507A2SM01 2-5 7-1 1) SWING MOTOR 994 488 469 117 121 118 114 706 707 702 712 472 355 351 052 993 106 438 432 444 106 471 443 303 748 747 A A 304 468 487 101 491 746 437 745 124 433 301 122 123 113 116 744 031 111 742 743 131 451 464 485 051 401 SECTION A - A 2507A2SM02 031 051 052 101 106 111 113 114 116 117 118 121 122 123 124 131... Pin 2 Bushing 2 14 15 16 17 18 19 20 21 22 23 24 25 26 Spring pin Thrust washer Carrier 1 Sun gear 1 Planet gear 1 Pin 1 Needle cage Side plate 1 Ring gear Knock pin Socket bolt Pinion gear Lock plate 2-5 7-3 27 28 29 30 31 32 33 34 35 36 37 Lock washer Hexagon bolt Plug Plug Side plate 2 Stop ring Spring pin Spring pin Gage bar Gage pipe Air breather assy 2 FUNCTION 1) ROTARY PART When high pressurized... Output torque(kgf cm) Z : Piston number(9EA) A : Piston area(cm2) : Tilting angle of swash plate(degree) S : Piston stroke(cm) Low pressure oil F1 High pressure oil F2 F 131 124 123 121 111 R290SM05(2) 2-5 7-4 2) MAKE UP VALVE In the system using this type of motor, there is no counter balance functioning valve and there happens the case of revolution exceeding hydraulic supply of motor To prevent the cavitation... plunger of MCV moves neutral position, the oil in the motor is drain via left relief valve, the drain oil run into motor via right make up valve, which prevent the cavitation of motor A B 29072SM09 2-5 7-5 ... D 8 5 Pg Sh 1 1 2 3 4 5 6 7 8 9 10 11 12 Swing control lever Swing control valve(MCV) Time delay valve Shuttle valve Spool Piston Poppet Spring Spring Orifice Spring Pilot pump 12 P3 2 2 4 25072SM06 2-5 7 GROUP 3 SWING DEVICE(Option) 1 STRUCTURE Swing device consists swing motor, swing reduction gear Swing motor include mechanical parking valve, relief valve, make up valve and time delay valve Swing . Plug30 Plug31 Side plate 232 Stop ring 33 Spring pin34 Spring pin35 Gage bar36 Gage pipe2418(B)2 930 9102 233 21 192 036 35 3 132 1 732 526271 634 781415 231 1 12 131 4562822)25072SM04 2-5 02.. PlugSECTION A - A48 535 5 35 1 401 131 744451051 031 301122 1 231 131 16 111 742 7 437 45 437 433 12410149174 630 448746 830 3A4 434 71A7487479 934 32444 438 106117121 118