Sk200-6 Pump & Regulator Explaining

7.HYDRAULIC COMPONENTS

7-1 Hydraulicpump

1. Appearance

a3 Dr PNl

7a5 PHl

i;

1

a5

0

i

PSVl

PSVl

Boltfor Back-up(M8)

a8 PSV2 PH2a6

./a

a9 PNBolt for Back-up(M8)

uLAEIpTa.a9

@

al Bla2

a5

/PH2

A3

3

PN

2

a9

K&

* @

#a

Dr3

*

W

*

a6

&

PNl

/

103 7-1

A3

2. Hydraulicdiagramof main pump

(FRONT) PSrla.A.a5PNl.I-T--

tnr;a8PNl

+_

I-J Il

_J

ll

a3

+

t[i_

J

PSV2A2a2 pN2a6

]

(REAR)

L

+

____J l

._L

1._+

a9

PN2

a41

rI -

l

lt ---

L

Dr BI B3 Dr3 A3

a7

unitMode] SK200-6 SK230-6 SK320-6

ModelMainpump K3Vl12DT-1RAP-9TIL K3Vl12DT-1RAP-9TOLK3Vl12DT-1RAP-9TOS

Gearpump ZXIOLGRZ2-06D

Displacementcc/rev 1052/10(Gearpump)1152/10(Gearpump)

Ratedspeed(Rotationdirection)min-1(rpm)

2,200(2,200)(C]ockwiseviewedfromshaftend)

2,100(2,100) 2,200(2,200)

Highid]ingmin-1(rpm)2,220(2,220)orlovv 2,300(2,300)orJovv 2,385(2,385)orlow

RatedpressureMPa(kgf/cm2)

Mainpump 34.3(350) I

Gearpump 4.9(50)

ATTboostpress.MPa(kgf/cm2)37.8(385)

rax8.flogT/rcaX)L/min2102/20(G.P) 2382/21(G.P)2502/22(G.P)Max.inputpowerkW(PS)

106.6(145)(incude 129(175)(include177(240)(includegearpumpinputtorque)gearpumpinputtorque)gearpumpinputtorque)/3.4(4.6)(gearpump) /3.4(4.6)(gearpump)/3.4(4.6)(gearpump)

.T?qxlnputNm(kgfm)509.6(52)(include 588.4(60)(incJude 735.3(75)(includegearpumpinputtorque)gearpumpinputtorque)gearpumpinputtorque)/14.7(1.5)(gearpump)/14.7(1.5)(gearpump)/14.7(1.5)(gearpump)

!inmnie.r.P.rceaSsSiunrgeMPa(kgf/cm2)AverageO.1(1)SurgeO.39(4)OilquantityincasingL 2.8 -

Controlcharacteristic Nega-Con/Totalpowershiftcontro]

WeightkgMainpump 125 126 I

Gearpump 1.6 +J

Note:G.P is Gearpump.

104 7-2

3. Structure

1)Mainpump53S ?B9

953

261

4C6

74

111

127

123

10

251

?32 532 214548 531 534 724 8CB

ILL-:_-:_1

A

I

U

901 954 1? 151 1S2

BB8

113

211

0

itJ_

I+

r`

).,-__

l

I

_-

212 49O ?17 153 1S6 1S?981

Code Name Q'ty

111Shaft(Front) 1

113Shaft(Rear) 1

114Sp]inejoint 1123 Rol[erbearlng

I

2

124 NeedlebeanngI

2

127I

BearlngSPaCer 4

141Cy)inderb[ock 2

151 Piston 18

152 Shoe 18

11i3Retainer 2156 Sphericalbushing2

157

Cylinderspnng 18

11Shoep[ate 2212Swashplate 2

214 Tiltingbushing2

251Support 2

261 Sealcover 1

271

Pumpcaslng 2

312 Valveblock 1

105

3 3 488

312 114 12 886

Code Name Q'ty

313Valveplate(Front)1

314Valveplate(Rear)1

325Cover 1

401Socketbot(M20210)8

406Socketbolt(M820)4

407Socketbolt(M630)3

466VPplug(PFl/4)2

468VPp]ug(PF3/4)4

490P)ug(Meek) 20

531 TiltingplnI

2

532 Servopiston 2

534Stopper(Large)2

535Stopper(Smal))2

546 Spacer 2

548 Feedbackp]nI

2

702 0IngI

2

7100-ring(JISB2401-G95)1

7170-ring(JISB2401-G145)4

7240-ring(JISB2401-P8)16

7-3

546

88S 314 141 211

325 ?2S

l I

rlI l

401

VW A

Code Name Q'ty

7250-ring(JJSB240l-Pll)7

7280-ring(JISB240l-P24)4

732 0-ring 2

774 Oi[sea] 1

789Back-upnng

2(J]SB2407-P18)

792Back-upr]ng

2(J[SB2407-G35)

806Nut(M16) 2

808Nut(M20) 2

824 Snaprlng

2

885Pin(812L) 2

886 SprlngPlnIll

4

901Eyebolt(M10) 2

953Setscrew 2

954 Setscrew 2

981 Nameplate 1

983 Rivet 2

2)Regulator

Structureof reguator

85

B9?

612

12

B

755 858

e:.'3:;A LB

614

615

813

811

VALVE ASSY. SOLENOID

YN35VOOO18F2)

646

?33

734

855

653

81

81

831

898

?32

4&

496 418

643 00

Section BB

644 645 7 8

92

801

E

654 836 851652 601624

Botfor back-up(Regularposition)

Bolt for back-u

Section DD

545

543

Section EE

(1nback-upcondition)

7-4

l

1l

Lal

625

Section AA

801

925

627

732

56

629 6) 628

626 887 763

-

-

I I

l

View C

Jr-

II

a3

PNl

P2

_J

+

Hydrauic diagram

438

l1

1+

Code Name Q'ty

412 scketbott(M850)2413 Socketbolt(M870) 2

418 Socketbo]t(M512) 2

436 Socketbolt(M650) 5

438 Socketbo[t(M620) 4

439 Socketbolt(M640) 4

466 VPplug(PFl/4) 3

467 Plug(PF3/8M8) 1

496 PIug 18

541 Seat 2

543 Stopperl 2

545 BalI 2

60lI

Caslng 1

611 Feedback[ever 1

612 Lever(l) 1

613 Lever(2) 1

614 FulcrampTug 1

615 Adjustplug 1

621 Compensatingpiston 1

622I

Pistoncas[ng 1

623 Compensatingrod 1

624 Springseat(C) 1

625I

Outersplng 1

626

lnnersprlng 1

627 PIunger(C) 1

628 Adjustscrew(C) 1629 Cover(C) 1

630 Locknut 1

63l Pfsleeve 1

641 PiLotcover 1

642 Rod 1

643 Pilotpiston 1

644 Springseat(Q) 1

645 PIunger(Q) 1

646 Pilotsprlng

1

651 Seeve 1

652 Spoo) 1

653 SprlngSeatI

1

4 IReturnspnng 1655

Setsprlng 1

656 Portplate 1

708 0-ring(JISB2401-G75) 1

722 0-ring(JISB2401-P6) 2

724 0-ring(JISB2401-P8) 12

725 0-ring(JJSB2401-Plo) 1

727 0-ring(JJSB2401-P14) 1

728 0-ring(JISB2401-P18) 1

107

Code Name Q'ty

730 0-ring(JISB2401-P22) 1

732 0-ring(JISB2401-P16)2733 0-ring(J[SB2401-P20) 2

734 0-ring(JISB240l-G25) 1

753 0-ring(JJSB2401-P9) 1

755 0-ring(JISB2401-Pll) 6

756 0-ring(J[SB2401-P26) 2

763 0-ring(JISB2401-G35) 1

801 Locknut(M8) 3

814 Snapring(JISB2804SR-15)1

836 Snaprmg

1

858 Lockingring(J[SB2804RR-15)2

874 Pin(411.7L) 1

875 Pin(48L) 4

887 Pin 1

897 Pin(419L) l

898 Pin(6.59L) 1

924 Setscrew 1

925 Setscrew(Ql) 1

079 So)enoidvalve 1

Tightemngtorque

Code SizeTorque

Nm(kgfm)412,413 M8 29.4(3)

436,438,439 M6 ll.8(1.2)

466 PFl/4 36.3(3.7)

467 PF3/8 73.5(7.5)

496 NPTFl/16 8.8(0.9)

630 M301.5 156.8(16)

801 M8 15.7(1.6)

7-5

Operationofregulator

HORSE POWER

COMP[NSTING LEVER

CONTROLPART

/

IlI

I

NEGATVECONTROL LEVER

r`

,A/ l

:@

*

SERVO PISTON

+

.+

OIL FLOWCONTROPART

F[DBACKLEVER

NGATIVE

CONTROSPOO SPOOL

lI

lI

I

l

L

J+ ...._.

-

-r

1

COMPENSAT(NG PISTON

I

i

Il

FEEDBACK LEVER

SERVO PISTON

COMPENSATINGROD

//

lJ

/

r

i

I

I

+

+

L=@l

!-+i)cT+

11

1

1. Feed back lever isconnected with3pins, spool attachingpin.Tiltingpin attachingtoservo piston, and pin reachingtolarge holesof negative controllever,and controllever.

2. Thenegative controllever isconnected with2pins,a pinfij(edon casing,andpinincontactwith negative control spoolgroovepart.

3.Thecompensatinglever isconnected with2pins,a pinfixedon casing,anda pin incontactwith compensating rodgroove part.

@ Conceptualdiagram forpump operation

Flowr8t8uP

Left

Large diameterSide

F)owratedown

Right

small diameterside

selfpressure

T8nkC Servopiston

Cylinder block

Self-pressure

SwashpJate

1 This isthemechanismtovarytheincationresultingfrommovmg servo piston right andleft.

2 That istherightmovementofservo pistonmakestheswsh plate vertical slightly reducingtheflowrate,andtheleftmovementmakestheincationof swash platelarger increaslng

theflowrate.

3.The diametersofservo pistonon rightandleftsidesdiffer,andare referredtoas the"smalldiameterside and"large diametersideforexplanation.

4. Onthesmalldiameterside,theself-pressureisalwaysgiven.

5. Now,theself-pressureisgiventothelarge diametersidelikethesmalldiameterside.Asa

result,theservo pistonmoves rightwardduetothedifferenceofarea reduclngthe flow

rate.

6.Byconnectingthelarge diametersidetotank, theservo pistonmoves leftward duetothedifferenceofpressureincreasmgtheflowrate.

7. Thepump havmgtheseactionsiscaueda variabledisplacementpump.

109 7-7

Regulatoroperation

532 SERVO-PISTON

LARGE DIAMFrER

651SLEEV

654 RETURNSPRJNG

652 SPOOL

621 COMPENSATINGP)STON

B98PJN

110

()

Pl

'

J

Cl

647 STOPPER

SMALL DIAMETER

@531T[LJtNGPIN

613 LEVERl611FEEDBACKLEVER

LEVER 1

/

/I

)

/

i(E)

875PJN

()

T

623COMPENSATINGROD

7-8

625OUTERSPRJNG

1NNERSPRING

874 PIN

646PJLOT SPRING

897 P

643P[LOTPJSTON

@531T)LT[NG P(N

548FEED BACK PIN

@ Conceptual diagramof regulator operation([ncaseof negativeflowratecontrol)

Selfpressure

@ Sleeve

Spool

Servopiston

C)

Large di8mete

Self-

l

A

/

l

reSSur

/

Smal

e)

I diamete

Negativecontrolpressure

Swashplate

Negativecontrolfever

Sprin

=+/

IJ

NegativecontrospooJ

Feedback ever

Theregulatorcan becontrolledbytaking thebalance forthe hydraulic forceandsprlngforce.

Eachregulatorisconnected withplnS.

1. Thenegative controllever isjoinedbypin securingthecasing and pin incontactwitha grooveofthenegative control spool.

2. The feedback lever isjoinedbypin attaching spool,tiltingpin attachedon theservo piston and pin throughuptothelarge holeparton thenegative controllevercompensatinglever.

3 Whiletheoperationlever issetinneutral,thenegative controlpressure rises pressingthespring,andmoves thenegativecontrol spool rightward.

4. Thenegativecontrollever moves rightwardmakingthepinsecuringthecasingtoful-Crum.

5. Then,thefeedback lever moves rightwardmakingthe tiltingpintofulcrum.

6.Therefore,thespool moves rightward.

7. Themovementof spool enablestheself-pressuretoreachtothelarge holeside ofservo

piston,andmoves theservo piston rightwardduetothedifferenceofarea.

8 Thetiltingangle of swsh plateisveryclosetovertical reducingtheflowrate.

9 Besides, bymovingtheservo piston rightward,thefeedback lever moves makingthepin tofulcrummog thepin 1eftward Therefore,itsmovement stops attheanglecorrespondingtothenegative controlpressure.

111 7-9

compensationcontrol(1)

COMP[NSrlNG ROD

PI CLI-- -

-

I

I

I

I

l

i__

COMPENSATING SPRING(

COMPENSATING SPRING

COMPENSTINGPITON

L

-

+ -

-

FOMIpL,puMP+-

Pl:Deliverypressure,P2:Companionpump pressure

P,(P,)PUMPDELIVERY PRESSURE

1. The deliverypressure(Pl)and companionpump pressure-(P2)actuatescompensatingpiston.

2. And,try tomove thepistontorightbyturnmgthecompensating rod.

3. However,as thespringforceof compensating spring isstrongerthan thatof piston,theflow inmaximumis delivered.

-J l

....1..l

L

L

LJl

_1_+ +

]T-

112 7-10

compensation control(2)

RETURN SPRING

COMPENSATINGVERSPOOL

COMPENSANG ROD

PI CL

COMPENSNGSPRING

COMPNSNG

SPRING@

L

P2

COMPNSnNGP!STN

LARGEDIAMETERCHAMBER

L37.R=

=PISTON

`

FEEDBACKEVR

9

f--.

SMALL DIAMETERCHAMBER

SWASH PLATE

Pl:Deiverypressure,P2:Companionpump pressure

Pl

Smalldiameterchamber;Alwaysactuatedbyself-pressure(Pl).

1. As thedelivery(Pl)and companionpump pressure(P2)is highertheforceofcompensat-ingspring.

2. Thecompensating rodmoves toright, and,

3.pin atcompensating rodgroove partalsomoves toright.

4. Then,compensatinglever ismovedtorightfulcrumthe fixedpinforcasing.

5. Pin alsomoves toright.(Feedback lever ismoved.)

6.Pin isconnected withthefeed back lever,so thespoolisalso movedtoright.

7. Pl(Delivery)CL- Large diameterchamber.

8. DeliverypressurePlactuatesboth faces(largediameter,smaudiameter).thentheservo

pistonmoves torightduetothedifferencearea.

9. Servopistonis directlyconnected withtiltingplate, andtheswash platewillbecloser and

closer perpendiculartothepiston.

10.The delivery flow isreduced.

113 7-ll

Compensationcontro(3) (Atsteadycondition)

RTURN SPRING SPOOL COMPENSATING LEVER

PI CLr-

1

L_

COMPNSANG SPRING

COMPENSATING SPRING

P2 Pl

SERVO PJSTON

L

_

..

----

J:

T-

FEEDBACKEVER

WASH PLATE

1.As soon astheservo pistonmoves toright,thefeed back leverconnected with pin alsomoves toright.

2. Pin moves toleft fulcrumthepin. (Spoolmoves toleft.)

3. (Pl)and(CL)portsareclosed.

4. Then,the tiltingplate winbesteadyon theangle corresponding platetothesummedpres-sure ofdeliverypressure(Pl)and companionpressure(P2).

114 7-12

@ Compensationcontrof(4) (Oj[f]owincreasing)

COMPENSJING LEVER

RTURN SPRING SPOOL

Pl

6;

COMPENSATING SPRJNG

COMPNSATING SPRING

P2 Pl E

COMPENSATINGR D

L..=

/

- l-

--. .-1

FEED BACK LEVR

a

Pl

1. Whenthesummedpressureofdelivery(Pl)andthecompanionpump pressure(P2)becomelowpressure.

2. Thespringpowerof compensating spring and isstrongerthan thesummedpressure,thecompensating rodismovedtoleft.

3.Pinalsomoves toleft.

4. Then,thecompensatinglevermoves toleft fulcrumthefixedpin forcasing.

5.

6.

7.

8.

9.

And,spoolismovedtoleft byreturn sprmg.

Largediameterchamber- CL- T (Tank).

Servopistonmoves toleft.

Theswash plate anglebecomes large.

The delivery flow is increased.

115 7-13

Powershift control

PIN

Pf

Pl CL

- `

I I

t>_

P2 Pl

L..(

-

P,

=

Pf:Powershiftpressure(M A B)

1. Controllerrecognizes audiggingmodes.

2. However,thepowershiftpressurecomingfromthesolenoid valveis fixed.

3. Thepressurecorrespondingtotheenginehorsepower(powershiftpressure)isconductedtoPl byactuating ofenginespeed sensing.(MechatronicsE.S.S)

4. Compensatingpistonmoves torightthroughpin.

5. Therefore,enginehorsepowerandpump horsepowerwbe fixed.

116 7-14

Negative flowcontrol

SLVE

RETURN SPRING

/ I

I

SPOOL

tl l

NGAVE CONTROLLVER

PI CLr-TI,I

_

Pi

I

IJl

_I =>

NEGATIVECONTROL SPOOL

NEGACONTR SPRING

L

I

ILARGEJDIAMETERCHAMBER

1'SRVOPISTON

+.._

FEED BACK[VR

'

SMA

T--

CHAMBER

ETER

SWASH PLATE Pl

Pi:Negativecontrol pressure,Small bore:OnepumpPIpressureactson itconstantly

1. Thenegative controlpressurerises.

2. Thenegative control spoolmoves rightward.

3.Pin on thenegative control spoolgroovesectionmoves rightward.

4. Then,thenegative controllevermoves rightwardtakingsecuring pin tothecasingas asupport.

5. Pin moves rightward.

6. Becausepin isconnectedtothefeedbacklever,thespoolalsomoves rightward.

7. Pl(Selfpressure)CL- Large bore.

8 Onepump pressurePlactson both facesofservo piston, andtheservo pistonmoves righ

ward.

9 Becausetheservo pistonis directlyconnected withtheswashplate,theswash plate

approaches verticauy.

10.The delivery flowratereduces.

And, thefeedback leverconnectedwith pin moves rightward concurrentlywiththemovementofservo pistonin ltem8,andthespoolmoves leftwardtakingpin as asupport.Toclosethe PlandCLports.

Therefore itis heldattheangle of swshplate correspondingtothenegativecontrolpressure.

117 7-15

Regulator operation Comparison when controlling pump propor- tional valve and back-up operation

1 ) Pump proportional valve control @ This is loaded flow rate control (negative

control) type that the delivery flow rate reduces when secondary pressure (Pi) of pump proportional valve rises.

@ Under the condition where the rod (642) is tightened, (See Figure), pump proportional valve secondary pressure (Pi) is led in pilot piston (643) and controls the pump delivery flow rate.

@ Pilot pressure (PSV) enters from the left a8 side, and is closed in A chamber with rod PN1 (642).

@ Negative control pressure (PN1) enters 1 ) Pump propo. valve from right side, and is closed in B controlled chamber with rod (642).

Therefore, the pump delivery flow rate is varied by the negative control/compensating 643 pressure which is calculated by deducting back pressure (Tn2) from negative control pressure (PN1).

PSV 2 ) Buck-up control function @ When CPU mechatro controller fails, re-

laxes rod (642) (See Figure), and the function changes into hydraulic pressure C' 642' TO piiot piston control. at propo. valve

control led @ The secondary pressure (Pi) circuit of the

pump proportional valve closes due to the movement of rod (642).

@ With the rises of one pump delivery pres- sure P1 and other pump delivery pressure, the pump delivery flow rate is reduced 2 ) When controlling automatically, and controls the input back-up function torque constant. (When the number of rotation is constant, the input power becomes constant.) 643

@ Pilot pressure (PSV) enters from the left side, and is led from A and C chambers P I : Self press. into pin (898), and acts on compensating P2 : Other press. piston (623), and finally the power is con- PSV: Pilot press. trolled to the constant power. PN1: Nega-Con press.

Therefore, the pump delivery flow rate is Pi : Secondary press, of propo. valve controlled by acting pilot pressure (PSV) 623 : Compensating piston and negative control pressure (PNl), and 642 : Rod (Screw) one pump pressure (PI) and other pump 643 : Pilot piston pressure (P2) on the compensating piston 898 : Pin (623) and pilot piston (643).

3)Gearpump(Forpi[otcontrol)

10 7 354 351

435 361 353

Drain

Suctionport:PF3/4

434

312

311

32

)9

ort:PF3/8

Oppositeside Sideof

Det

310

ofcauJkingcaulking

ailoffiJter

Code Name Q'ty

307 Poppet l

308 Seat 1

309 Spnngseat

l

310 Sprlng

1

31l Adjustscrew 1312 Locknut 1

351 Gearcase 1

353 Drivegear 1

354 Drivengear 1

355 Filter 1

361 Frontcase 1

433 SocketboJt(M840) 2

434 Socketbolt(M855) 2

435 Socketbolt(M820) 4

466 Plug(PFl/4) 1

467 Adapter(PFl/2-PF3/8) 1

700 SquarenngI

1

710 0-ring(JJSB2401-G95) 1

725 0-ring(JISB240l-Pll) 1

728 0-ring(JISB2401-P18) 1

732 0-ring(JJSB2401-P16) 1850 Lockingring(JJSB28041RR-18)1

119

////////

435

-

- -

----

////

///

7,/

(:@

-

l

DeliveryportPF3/8

433

lltl

/I;=

307 )8355 4& 850 66725 2867

Note:

1. Afterassembly of gear pump, checkthatthedrivegearrotatessmoothlyat0.1 N.m

(1.Okgfm)oess.2 Afterassemb)y of gearpump, apply oil

sufficient(yon thesliding section.

3 Bringtheoppositesideofcaulkingofthefi[tershownintheleft figure intocontactwjththe insertendface,paylngattention

totheinstallingdirection.

A3

a3

II

l

,_..!IlI

Il

l

l

l

1I

!,,I

L__TlJB3

Hydrauliccircuit

Tighteningtorque

Dr4

Code ThreadsizeTorqueNm(kgfm)

312 M141.5 29.4(3.0)433,434

M8 16.7(1.7)435466 PFl/4 15.7(1.6)

7-17