SANY Crawler Hydraulic Excavator SY365H-9, SY365BH-9. Shop Manual (2014)

4-32

Structure and Functions

SY365(B)H-9 Crawler Hydraulic Excavator

ZX215-1002021

ZX215-1002022

ZX215-1002023

4.4.3.4 Operating principle

●

Cylinder block (7) rotates together with
shaft (1), and slipper (5) slides on

at sur-

face (A).

●

When this happens, swash plate (4) moves
along cylindrical surface (B), so angle (a)
between central line (X) of swash plate (4)
and the axial direction of cylinder block (7)
changes.

●

(a) stands for the angle of the swash plate.

●

With central line (X) of swash plate (4) at
a swash plate angle (a) in relation to the
axial direction of cylinder block (7),

at sur-

face (A) acts as a cam in relation to slipper
(5).

●

In this way, plunger (6) slides on the in-
side of cylinder block (7), so a difference
between volumes (E) and (F) is created
inside cylinder block (7).

●

A single plunger sucks and discharges the
oil by the amount (F) – (E).

●

As cylinder block (7) rotates and the vol-
ume of chamber (E) becomes smaller, the
pressurized oil is discharged.

●

On the other hand, the volume of chamber
(F) grows larger and, in this process, the
oil is sucked in.

●

As central line (X) of swash plate (4) over-
laps the axial direction of cylinder block (7)
(swash plate angle (a) = 0), the difference
between volumes (E) and (F) inside cylin-
der block (7)becomes 0.

●

Suction and discharging of pressurized
oil is not carried out in this state. Namely
pumping action is not performed. (In real-
ity, however, the swash plate angle is not
set to 0)

Fig. 4-19

Fig. 4-20

Fig. 4-21

4-35

Structure and Functions

SY365(B)H-9 Crawler Hydraulic Excavator

4.4.5 Regulator

W365P130701

438

646

079

B-B

418

496

439

413

757

438

656

722 543

876

874

612

412

897

755 545 541

724

725

438

730

643

708

644

645

728

801

924

627

753

756

763

887

626

625

623

621

622

733

732

631

898

875

611

613

614

755

858

615 814

641

655

653

734

654 836 651

A-A

652

601

624

629

630

628

802

755
466

545

543

755 541

E-E

D-D

ൟো

642

DETAIL OF STAMP FOR TYPE
AND SERIAL NUMBER

SERIAL NUMBER

ᑣ߫ো

753

467,727

601

TYPE

Fig. 4-24

4-36

Structure and Functions

SY365(B)H-9 Crawler Hydraulic Excavator

No.

Part name

Material

Quantity

Part code

Remark

—

Regulator

Alloy steel

412

Screw, socket head

Alloy steel

60150559

JIS B1176 M8-50

413

Screw, socket head

Alloy steel

60150560

JIS B1176 M8-70

418

Screw, socket head

Alloy steel

60150556

JIS B1176 M5-12

438

Screw, socket head

Alloy steel

60150557

JIS B1176 M6-20

439

Screw, socket head

Rolled steel

60150558

JIS B1176 M6-35

466

Plug

Rolled steel

60008724

G1/4

467

Plug

Carbon steel

60008507

G3/8

496

Plug

Alloy steel

60008728

497

Plug

Alloy steel

541

Seat

Alloy steel

60008884

543

Stopper 1

Alloy steel

60008885

545

Steel ball

Bearing steel

601

Housing

Cast iron

60197213

611

Feedback rod block

Alloy steel

60075481

612

Lever

（

）

Alloy steel

60008532

613

Lever

（

）

Alloy steel

60008522

614

Pivot pin

Carbon steel

60008533

615

Compensation pis-

ton

Carbon steel

60008534

621

In-cavity piston

Alloy steel

60008535

622

Piston shell

Cast iron

60008536

623

Compensation piece

Alloy steel

60008524

624

Spring seat

（

）

Alloy steel

60008494

625

Outer spring

Spring steel

626

Inner spring

Spring steel

60075415

627

Adjusting ring

（

）

Carbon steel

60008526

628

Adjusting bolt

（

）

Carbon steel

60008497

629

Cover

（

）

Aluminum al-

loy

60008529

630

Locknut

Rolled steel

60008537

631

PF sleeve

Cast iron

60150553

641

Guide cover

Aluminum al-

loy

60008510

642

Valve stem

Carbon steel

B229900001021

643

Guid piston

Alloy steel

60008520

644

Spring seat

（

）

Alloy steel

60008495

645

Adjusting ring

（

）

Carbon steel

60197211

4-37

Structure and Functions

SY365(B)H-9 Crawler Hydraulic Excavator

No.

Part name

Material

Quantity

Part code

Remark

646

Guide spring

Spring steel

651

Sleeve

Alloy steel

60008503

652

Spool

Alloy steel

60008538

653

Spring seat

Carbon steel

60008539

654

Reset spring

Spring steel

60008541

655

Adjusting spring

Spring steel

60008540

656

Cover plate

Cast iron

60008548

708

O-ring seal

NBR

60008694

JISB 2401

722

O-ring seal

NBR

60008707

JISB 2401

724

O-ring seal

NBR

JISB 2401

725

O-ring seal

NBR

60008696

JISB 2401

727

O-ring seal

NBR

60008700

JISB 2401

728

O-ring seal

NBR

60008702

JISB 2401

730

O-ring seal

NBR

60008704

JISB 2401

732

O-ring seal

NBR

60008701

JISB 2401

733

O-ring seal

NBR

60221603

JISB 2401

734

O-ring seal

NBR

60008692

JISB 2401

753

O-ring seal

NBR

60008709

JISB 2401

755

O-ring seal

NBR

60008697

JISB 2401

756

O-ring seal

NBR

60008706

JISB 2401

757

O-ring seal

NBR

60008698

JISB 2401

763

O-ring seal

NBR

60039416

JISB 2401

801

Nut, hexagon

Rolled steel

60150561

JIS B1181 RN-M8

802

Nut, hexagon

Rolled steel

60008506

M10

814

Collar

Tool steel

60009938

JIS B 2B04 SR-10

836

Collar

Tool steel

60008748

858

Collar

Tool steel

60009937

JIS B 2B04 RR-15

874

Bearing steel

60008734

11.7L

875

Bearing steel

60008733

876

Bearing steel

60008735

887

Carbon steel

60008546

897

Bearing steel

60008736

19L

898

Bearing steel

60150562

8.5

10L

924

Screw, socket head

Alloy steel

60008743

079

Pressure-reducing

solenoid valve

60125194

041

Check valve block

60117792

4-38

Structure and Functions

SY365(B)H-9 Crawler Hydraulic Excavator

Operating principle

●

The regulator controls the

ow of the main

pup through various pressure signal com-
mands, keeping the pump

’

s driving pow-

er lower than the engine power

●

Pump 1 and pump 2 are each equipped
with a regulator. Primary components of
the regulator are electromagnetic propor-
tional pressure-reducing valve (1), electro-
hydraulic converter valve (2), variable
power regulator (3), positive

ow regulator

(4), servo piston (5) and servo directional
valve (6). The regulator opens or closes
the oil passage of servo piston (5) accord-
ing to various pressure signal commands,
change the inclination of swash plate, and
control the

ow of pump as a result.

W365P130702

Psv

Fig. 4-25

Components of control mechanism

Electric current

ow control: when normal

By changing the value I of command current

owing to the electromagnetic proportional pres-

sure reducing valve, the inclination angle (output

ow) of pump can be controlled freely. This is a

regulator featured with positive

ow control (forward control), in which the output

ow Q increases

with the value I of command current. With such a device, when you input a current necessary for

ow required by corresponding operation, the pump only delivers a

ow as desired and no power

will be wasted.

Power control (+ power shift): For emergency (with rod pulled out)

●

In case of emergency, the power shift command pressure Pf is used to change the value of
power setting. The power shift command pressure (secondary pressure P2 of electromagnetic
proportional pressure reducing valve) is introduced via in-pump passage to the power control
component of each regulator and shifted to respective similar power setting value.

●

When power shifting is being performed, the rising of self-pump output pressure Pd1 automat-
ically reduces the inclination (output

ow) of the pump. As a result, the input torque is limited

under certain value. (In case of constant speed, the input power becomes constant too.)

●

When power control is exercised, regulator of each pump is controlled to the same inclina-
tion (output

ow). Therefore, power control is performed irrelevant to the load of both pumps.

Overload of prime mover is prevented as a result. In addition, the normal pressure for power
shift is 0 MPa. So the power control is inactive in normal hours.

●

With this mechanism, optimum power can be achieved in butting operation.

Although the regulator has the two control mechanisms described above, each control in joint ac-
tion can put small inclination (

ow) command to priority via mechanical calculation.

4-40

Structure and Functions

SY365(B)H-9 Crawler Hydraulic Excavator

Maximum flow adjustment (pump body
side)

●

Loosen the hex nut (808). Tighten (or
loosen) socket-headed setscrew (954). No
control characteristics except the maximum

ow changes.

Minimum flow adjustment (pump body
side)

●

Loosen the hex nut (806). Tighten (or
loosen) the socket-headed setscrew (953).
Though this action is the same as the ad-
justment of maximum

ow and all the other

control characteristics do not change,
power required for maximum output pres-
sure (at relief) is likely to increase if over-
tightened. Be careful in this case.

Input power

1) Adjustment of the outer spring

Loosen the nut (630) and tighten or loosen the
screw (C) (628) to perform adjustment. When
screw (C) (628) is tightened, the control line,
as shown in the right

gure, moves rightward.

The input power increases. Moreover, When
the screw (C) (628) is turned by N turns, in-
ner spring (626) also changes along with its
setting. So turn the adjusting wheel (C) (627)
in the opposite direction by N

A turns. (For

value of A

“

Annexed Table: Regulator ad-

justing values

”

on page 4-47

W365P130703

Command current I

Output flow Q

W365P130704

Command current I

Output flow Q

W365P130705

Output pressure (Pd1)

Output flow Q

Fig. 4-27

Fig. 4-28

Fig. 4-29

4-42

Structure and Functions

SY365(B)H-9 Crawler Hydraulic Excavator

Increasing the

When the negative feedback pressure Pi2
reduces, the pilot plunger (643) will move in
direction A until a relative balance between
P2 and the resilient force of the guide spring
(646) is achieved. The movement of the pilot
plunger is transmitted to lever (2) (613) via pin
(875) and rotates towards the arrow direction
with B as the pivot. The movement of lever (2)
is transmitted to the feedback rod (611)via pin
shaft (897) and rotates in the same direction of
B with C as the pivot. Along with this, the spool
(652) connected to the feedback rod moves to-
wards direction D. The spool moving in direc-
tion D connects port C1 with the oil tank port,
and the pressure inside the large diameter end
of the servo piston is relieved. As a result, the
output pressure Pd1 inside the small diameter
end moves the servo piston (532) in direction
E and flow is increased. Since the feedback
rod is connected with the servo piston and the
spool, movement of the servo piston in direc-
tion E makes the feedback rod rotate with F
as the pivot. In this way, the spool is moved to
the original position. Through this movement,
the opening portion between the spool and the
valve block is closed slowly. The servo pis-
ton stops moving when the opening portion is
completely closed.

W365P130709

646

613

897

876

875

611

652

643

532

Port C1 connected with
head end of servo piston

Psv

W365P130710

Fig. 4-33

Fig. 4-34

4-43

Structure and Functions

SY365(B)H-9 Crawler Hydraulic Excavator

Decreasing the

When the negative feedback pressure Pi2
rises, the pilot plunger (643) will move in di-
rection G until a relative balance between P2
and the resilient force of pilot spring (646) is
achieved. The movement of pilot plunger is
transmitted to the feedback rod (611) via pin
(897) and rotates in the same direction as H
with I as the pivot. Along with this, spool (652)
connected to the feedback rod moves in direc-
tion J. If the spool moves in direction J, output
pressure Pd1 enters the large diameter end
of the servo piston through the spool and port
C1. On the other hand, output pressure Pd1
enters the small diameter end of the servo pis-
ton. As a result of the area difference, the ser-
vo piston moves in direction K and the inclina-
tion is reduced, and the

ow is also reduced.

Since the feedback rod, the servo piston and
the spool form a whole unit, when the servo
piston is moving in direction K, the feedback
rod rotates with L as the pivot. This makes the
spool move to its original position. As a result,
the opening portion between the spool and the
valve block is slowly closed. The servo pis-
ton stops moving when the opening portion is
completely closed.

W365P130711

646

613

897

876

875

611

652

643

532

Port C1 connected with
head end of servo piston

Psv

W365P130712

Fig. 4-35

Fig. 4-36

4-45

Structure and Functions

SY365(B)H-9 Crawler Hydraulic Excavator

Action against overloading

When the self pump output pressure Pd1 in-
creases, the output pressure Pd1 is acted onto
the ladder portion of the offset piston (621) ,
and as a result, the offset rod (623) moves in
direction M until the output pressure Pd1 bal-
ances the elastic forces of outer spring (625)
and inner spring (626). The movement of the
offset rod is transmitted to the lever (1) (612)
via pin (875) and rotate in the arrow direction
with N as the pivot. Then, the movement of
lever (1) is transmitted to feedback rod (611)
via pin (897) and rotates in the same arrow
direction as N with O as the pivot. Along with
this, spool (652) which is connected to the
feedback rod moves in direction P. If the spool
moves in direction P, output pressure Pd1
enters the large diameter end of the servo pis-
ton through the spool and port C1. However,
output pressure Pd1 enters the small diam-
eter end of the servo piston, and as a result
of the area difference, the servo piston moves
in direction Q. The inclination is reduced as a
result and the

ow is also reduced. Since the

feedback rod, the servo piston and the spool is
a whole unit, when the servo piston is moving
in direction Q, the feedback rod rotates with R
as the pivot. This allows the spool to move to
its original position. Through this movement,
the opening portion between the spool and the
valve block is slowly closed. The servo pis-
ton stops moving when the opening portion is
completely closed.

W365P130714

897

652

876

612 626

625

875

623

611

532

621

(For emergency)

Port C1 connected with
head end of servo piston

W365P130715

Psv

Fig. 4-38

Fig. 4-39

4-46

Structure and Functions

SY365(B)H-9 Crawler Hydraulic Excavator

Action of

ow recovery

When the self pump output pressure Pd1
drops, elastic force offset rod (623) of outer
spring (625) and inner spring (626) moves in
direction S to a point where the elastic force of
the outer spring and the inner spring balances
the output pressure Pd1. The movement of
the offset rod (623) is transmitted to lever (1)
(612) via pin (875) and rotates in the arrow
direction with T as the pivot. Then, the move-
ment of lever (1) is transmitted to feedback
rod (611) via pin (897) and rotates in the same
arrow direction as T with U as the pivot. Along
with this, spool (652) which is connected to
the feedback rod moves in direction V. If the
spool is moving in direction V, port C1 is con-
nected with the tank port, and the pressure
inside the large diameter end of the servo pis-
ton is relieved as a result. Servo piston (532)
moves in direction W through the output pres-
sure Pd1 of the small diameter end. The

is increased in this way. Since the feedback
rod, the servo piston and the spool is a whole
unit, if the servo piston is moving in direction W,
the feedback rod will rotate with X as the pivot.
This allows the spool to move to its original
position. Through this movement, the opening
portion between the spool and the valve block
is slowly closed. The servo piston stops mov-
ing when the opening portion is completely
closed.

Prior mechanism of small inclination (small

ow) command

●

As described above, though the inclination command of delivery control and power control is
transmitted to the feedback rod (611) and spool (652) via lever (2) (613) and the big diameter
end of lever (1) (612) respectively, pin (

5) on the big hole (

9) , as a protrusive structure,

only contacts with the rod and pin at the small inclination side. It does not contact with the rod

9 and pin (897) on the large inclination side. Through this mechanical option, the inclination

command of the delivery control and power control is placed in priority.

W365P130716

652

897

876

612 626

625

875

623

611

532

621

(For emergency)

Port C1 connected with
head end of servo piston

W365P130717

Psv

Fig. 4-40

Fig. 4-41

4-47

Structure and Functions

SY365(B)H-9 Crawler Hydraulic Excavator

ZX335-1002029

Output flow Q

Output pressure (Pd1)

Power shift control (power control reduc-
tion)

●

As shown in the right diagram, the power
of the pump can be set freely through pow-
er shift pressure Pf.

●

If the power shift pressure Pf is increased,
compensating rod (623) will be pushed to
the right side via pin (898) and the offset
piston (621). Through the same action as
described in the power control overload-
ing prevention, the power set value can be
reduced by reducing pump inclination. On
the contrary, the power set value can be
increased by reducing the power shift pres-
sure Pf.

●

When the pump is under normal condition,
the power shift pressure Pf is 0 MPa. In an
emergency, the power shift pressure Pf is
4.9 MPa.

Fig. 4-42

Annexed Table: Regulator adjusting values

Model of regulator

KR3K-9T06-V

RPM (min-1)

2100

Max

ow regulation

Adjusting screw (954) screw-in (rotation)

+1/4

Delivery change (l/min-1)

Min

ow regulation

Adjusting screw (953) screw-in (rotation)

+1/4

Delivery change (l/min-1)

+4.8

Adjustment
of input
horse power

Adjustment of
outer spring

Adjusting screw (928) screw-in (rotation)

+1/4

Compensation control initial pressure
change (MPa)

+1.88

Input torque change (N·m)

+50.8

1.87

Adjustment of
inner spring

Adjusting wheel (627) screw-in (rotation)

+1/4

Flow change (l/min-1)

+10

Input torque change (N·m)

+39

Adjustment of

ow control

characteristics

Adjusting screw (924) screw-in (rotation)

+1/4

Flow control initial current change (mA)
(Secondary pressure of proportional valve)

Around 35mA

（

+0.18

）

Delivery change (l/min-1)

-19.4

SANY Crawler Hydraulic Excavator SY365H-9, SY365BH-9. Shop Manual (2014) - page 8