FUNCTION OF 2-STAGE SUCTION-SAFETY VALVE OF CONTROL VALVE
“Port (B) of the boom valve and port (B) of the service valve”
• Pressure is set to 2 stages.
• Low-pressure set is obtained by receiving pilot pressure from the attachment selector solenoid valve.
• The set pressure can be changed by turning ON/OFF the pilot pressure, corresponding to the types of the
attachments (for examples, breaker and crusher).
• The set pressure depends on the load at installed height of spring (1). (High-pressure side)
• The set pressure on the low-pressure side depends on the moving distance of the piston (2).
OPERATION OF 2-STAGE SUCTION-SAFETY VALVE OF CONTROL VALVE
When pilot pressure (P) is cut off (high pressure setting)
1.
Since pilot pressure (P) is cut off, piston (2) is pressed to
the left by the reaction force of spring (3). “Load at instal-
led height of spring (1) load < Load at installed height of
spring (3)”
2.
Load at installed height of spring (1) is maximum so that
the set pressure increases.
3.
Passage (B) is connected to the drain circuit via chamber
(C) and chamber (D).
When pilot pressure (P) is supplied (low pressure setting)
1.
Pilot pressure (P) is supplied, and it is sent through pas-
sage (B) to (A) part.
2.
Pilot pressure acts on the pressure receiving diameter (A)
part “(d1)-(d2)” of piston (2).
3.
Piston (2) is applied the pilot pressure, compresses the
spring (3), and moves to the right until it contacts to the
holder (4).
4.
Set pressure decreases since the tension of spring (1) is
lowered and the load at installed height decreases.
5.
Pressurized oil caused by the stroke of piston (2) is
drained through the passage (C) and the chamber (D).
A E P 2 1 6 3 1
A E P 2 1 6 3 2
COMPONENT PARTS OF HYDRAULIC SYSTEM
10 STRUCTURE AND FUNCTION
10-190
PC500LC-10R
Summary of Contents for PC500LC-10R
Page 1: ...HYDRAULIC EXCAVATOR SEN06722 00 PC500LC 10R SERIAL NUMBERS 100001 and up...
Page 2: ......
Page 3: ...00 INDEX AND FOREWORD PC500LC 10R 00 1...
Page 76: ......
Page 77: ...01 SPECIFICATIONS PC500LC 10R 01 1...
Page 94: ......
Page 95: ...10 STRUCTURE AND FUNCTION PC500LC 10R 10 1...
Page 177: ...When balanced 10 STRUCTURE AND FUNCTION CLSS PC500LC 10R 10 83...
Page 178: ...When lever is returned to fine control state CLSS 10 STRUCTURE AND FUNCTION 10 84 PC500LC 10R...
Page 179: ...When lever is pulled at a stroke 10 STRUCTURE AND FUNCTION CLSS PC500LC 10R 10 85...
Page 180: ...When lever is in stroke end CLSS 10 STRUCTURE AND FUNCTION 10 86 PC500LC 10R...
Page 377: ...20 STANDARD VALUE TABLE PC500LC 10R 20 1...
Page 407: ...30 TESTING AND ADJUSTING PC500LC 10R 30 1...
Page 583: ...30 TESTING AND ADJUSTING METHOD FOR STARTING UP KOMTRAX TERMINAL PC500LC 10R 30 177...
Page 604: ......
Page 605: ...60 MAINTENANCE STANDARD PC500LC 10R 60 1...
Page 636: ...MAINTENANCE STANDARD OF MAIN PUMP 60 MAINTENANCE STANDARD 60 32 PC500LC 10R...
Page 638: ...MAINTENANCE STANDARD OF SWING MOTOR 60 MAINTENANCE STANDARD 60 34 PC500LC 10R...
Page 641: ...60 MAINTENANCE STANDARD MAINTENANCE STANDARD OF TRAVEL MOTOR PC500LC 10R 60 37...
Page 644: ...MAINTENANCE STANDARD OF CONTROL VALVE 60 MAINTENANCE STANDARD 60 40 PC500LC 10R...
Page 646: ...MAINTENANCE STANDARD OF CONTROL VALVE 60 MAINTENANCE STANDARD 60 42 PC500LC 10R...
Page 648: ...MAINTENANCE STANDARD OF CONTROL VALVE 60 MAINTENANCE STANDARD 60 44 PC500LC 10R...
Page 650: ...MAINTENANCE STANDARD OF CONTROL VALVE 60 MAINTENANCE STANDARD 60 46 PC500LC 10R...
Page 652: ...MAINTENANCE STANDARD OF CONTROL VALVE 60 MAINTENANCE STANDARD 60 48 PC500LC 10R...
Page 658: ...MAINTENANCE STANDARD OF TRAVEL PPC VALVE 60 MAINTENANCE STANDARD 60 54 PC500LC 10R...
Page 668: ...MAINTENANCE STANDARD OF WORK EQUIPMENT LINKAGE 60 MAINTENANCE STANDARD 60 64 PC500LC 10R...
Page 679: ...90 CIRCUIT DIAGRAMS PC500LC 10R 90 1...
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Page 704: ...Symbol Content Buzzer Antenna SYMBOLS USED IN ELECTRICAL CIRCUIT DIAGRAM 90 26 PC500LC 10R...
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