S0709730K
Page 5
Power Steering Unit
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Neutral Operation
With the steering wheel in the neutral position (wheels turned neither right nor left), the spool (2, Figure 3)
and sleeve (1) are stationary at the position where the center pin (6) becomes centered in the spool space
by the centering springs (3). Oil flow through the load sensing line (LS), port L, port R, and port T are
bypassed to the tank line and the oil supply (P) is blocked by the directional spool in the steering unit (1,
Figure 2). Even if an external force is applied to the steering cylinder, the steering unit is protected because
the oil path is blocked by the directional spool.
Right Turn
The spool (2, Figure 3) is engaged with the spline of the steering shaft. When the steering wheel is turned
to the right, the spool turns. The sleeve (1) is connected to the spool (2) by centering springs (3). When
spool turns, the sleeve turns. The sleeve turning angle is about 10° less than the spool turning angle. This
allows the longitudinal slots in the spool to align with the ports in the sleeve. Oil from port P on the steering
unit (1, Figure 2) travels through the control spool and is directed to port R which directs the oil to the
steering cylinders (3, Figure 2). The amount of flow metered to port R is controlled by the amount of
steering wheel rotation. Excess oil flow through port P that is not metered to port R, is directed by the spool
to port T and is then directed through the il cooler and into the tank.
Left Turn
The spool (2, Figure 3) is engaged with the spline of the steering shaft. When the steering wheel is
connected to the spool (2) by centering springs (3). When the spool turns, the sleeve turns. The sleeve
turning angle is about 10° less than the spool turning angle. This allows the longitudinal slots in the spool to
align with the ports in the sleeve. When the steering wheel is turned to the left, oil from port P on the
steering unit (1, Figure 2) is directed through the control spool in the steering unit, out port L and into the
steering cylinders (3, Figure 2). The amount of oil flow metered to port L is controlled by the amount of
steering wheel rotation. Excess oil flow through port P that is not metered to port L, is directed by the spool
to port T and is then directed through the oil cooler and into the tank.
GEROTOR OPERATION
If the engine or pump is not operating, the steering unit (1, Figure 2) works as a manual pump when the
steering wheel is turned. The gerotor will work when the input torque to the steering wheel is less than 12
kg•m (87 ft lb). If the necessary input torque is greater than this, the gerotor will not function. When the
steering wheel is turned, the gerotor creates a vacuum that draws oil from port T. See Figure 2. The gerotor
pumps this oil through the control spool and into the steering cylinders. Return oil flows back to the spool
and is used to lubricate the steering unit (1, Figure 2). The return oil then flows back into the tank line and
is recirculated back to the gerotor and the steering cylinders.
Reference
Number
Description
1
Sleeve
2
Spool
3
Centering Spring
4
Spool
5
Sleeve
6
Center Pin
7
Drive shaft
Figure 3
Summary of Contents for Mega 500-V
Page 4: ...1SAFETY ...
Page 41: ...1SPECIFICATIONS ...
Page 47: ...S0203070K Page 6 Specifications for Mega 500 V ENGINE PERFORMANCE CURVES AHS3720L Figure 2 ...
Page 55: ...S0203070K Page 14 Specifications for Mega 500 V ...
Page 56: ...1GENERAL MAINTENANCE ...
Page 70: ...S0302000 Page 14 General Maintenance Procedures Return to Master Table of Contents ...
Page 83: ...1UPPER STRUCTURE ...
Page 85: ...S0403040K Page 2 Counterweight TABLE OF CONTENTS Specifications 3 Counterweight 3 ...
Page 87: ...S0403040K Page 4 Counterweight ...
Page 98: ...1LOWER STRUCTURE AND CHASSIS ...
Page 104: ...S0502020K Page 6 Center Joint Articulation Joint ...
Page 105: ...1ENGINE AND DRIVE TRAIN ...
Page 118: ...S0602170K Page 13 Axle ZF AP 420R Figure 9 ...
Page 119: ...S0602170K Page 14 Axle ZF AP 420R ...
Page 121: ...S0602170K Page 16 Axle ZF AP 420R FINAL DRIVE AP 407 409 Figure 10 ...
Page 123: ...S0602170K Page 18 Axle ZF AP 420R AP 411 415 Figure 11 ...
Page 125: ...S0602170K Page 20 Axle ZF AP 420R AP 417 420 Figure 12 ...
Page 129: ...S0602170K Page 24 Axle ZF AP 420R Differential Carrier RK Figure 14 ...
Page 131: ...S0602170K Page 26 Axle ZF AP 420R Differential Carrier DK ...
Page 135: ...S0602170K Page 30 Axle ZF AP 420R Differential Carrier HK Figure 16 ...
Page 178: ...S0602170K Page 73 Axle ZF AP 420R ILLUSTRATED TABLE Figure 152 ...
Page 194: ...S0602170K Page 89 Axle ZF AP 420R ILLUSTRATED TABLE Figure 196 ...
Page 210: ...S0602170K Page 105 Axle ZF AP 420R ILLUSTRATED TABLE Figure 242 ...
Page 225: ...S0602170K Page 120 Axle ZF AP 420R ILLUSTRATED TABLE Figure 289 ...
Page 251: ...S0605050K Page 26 Air Conditioner Return to Master Table of Contents ...
Page 261: ...S0607080K Page 10 Transmission and Torque Converter ZF 4WG 310 Figure 2 ...
Page 264: ...S0607080K Page 13 Transmission and Torque Converter ZF 4WG 310 ...
Page 271: ...S0607080K Page 20 Transmission and Torque Converter ZF 4WG 310 ...
Page 296: ...S0607080K Page 45 Transmission and Torque Converter ZF 4WG 310 ...
Page 447: ...S0607900C Page 36 Transmission Error Codes ZF ...
Page 448: ...1HYDRAULICS ...
Page 478: ...S0705010 Page 22 Cylinders Return to Master Table of Contents ...
Page 489: ...S0708460K Page 11 Main Pump Denison T6DMY Series ...
Page 490: ...S0708460K Page 12 Main Pump Denison T6DMY Series PARTS LIST Figure 8 ...
Page 504: ...S0708460K Page 26 Main Pump Denison T6DMY Series ...
Page 508: ...S0708470K Page 4 Steering and Brake Pump Denison T67DB Series PARTS LIST Figure 2 ...
Page 514: ...S0708470K Page 10 Steering and Brake Pump Denison T67DB Series DISASSEMBLY Figure 5 ...
Page 521: ...S0708470K Page 17 Steering and Brake Pump Denison T67DB Series ...
Page 522: ...S0708470K Page 18 Steering and Brake Pump Denison T67DB Series REASSEMBLY Figure 15 ...
Page 528: ...S0708470K Page 24 Steering and Brake Pump Denison T67DB Series ...
Page 548: ...S0709476K Page 2 Pilot Control Valve Return to Master Table of Contents ...
Page 554: ...S0709476K Page 8 Pilot Control Valve Return to Master Table of Contents ...
Page 557: ...S0709665K Page 3 Flow Amplifier Danfoss GENERAL DESCRIPTION Figure 1 ...
Page 558: ...S0709665K Page 4 Flow Amplifier Danfoss PARTS LIST Figure 2 ...
Page 609: ...S0709730K Page 7 Power Steering Unit Return to Master Table of Contents ...
Page 632: ...S0709730K Page 30 Power Steering Unit Return to Master Table of Contents ...
Page 638: ...S0709750K Page 6 Restriction Valve Return to Master Table of Contents ...
Page 644: ...S0793060K Page 6 Hydraulic Schematic Mega 500 V Return to Master Table of Contents ...
Page 645: ...1ELECTRICAL SYSTEM ...
Page 654: ...S0802190K Page 9 Electrical System Return to Master Table of Contents ...
Page 658: ...S0802190K Page 13 Electrical System Return to Master Table of Contents ...
Page 676: ...S0802190K Page 31 Electrical System Return to Master Table of Contents ...
Page 685: ...S0893060K Page 6 Electrical Schematic Mega 500 V Return to Master Table of Contents ...
Page 686: ...1ATTACHMENTS ...