JPS56138477A - Controller of variable capacity pump-motor - Google Patents

Controller of variable capacity pump-motor

Info

Publication number
JPS56138477A
JPS56138477A JP4048080A JP4048080A JPS56138477A JP S56138477 A JPS56138477 A JP S56138477A JP 4048080 A JP4048080 A JP 4048080A JP 4048080 A JP4048080 A JP 4048080A JP S56138477 A JPS56138477 A JP S56138477A
Authority
JP
Japan
Prior art keywords
motor
low pressure
capacity
pump
controller
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
JP4048080A
Other languages
Japanese (ja)
Other versions
JPS646346B2 (en
Inventor
Takashi Kanai
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hitachi Construction Machinery Co Ltd
Original Assignee
Hitachi Construction Machinery Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Hitachi Construction Machinery Co Ltd filed Critical Hitachi Construction Machinery Co Ltd
Priority to JP4048080A priority Critical patent/JPS56138477A/en
Publication of JPS56138477A publication Critical patent/JPS56138477A/en
Publication of JPS646346B2 publication Critical patent/JPS646346B2/ja
Granted legal-status Critical Current

Links

Landscapes

  • Reciprocating Pumps (AREA)
  • Control Of Positive-Displacement Pumps (AREA)

Abstract

PURPOSE: To control the capacity of a pump-motor without reducing its efficiency by connecting two actuators with a low pressure source through check valves as well as with a tank through selector valves.
CONSTITUTION: Two actuators 12, 13 controlling the capacity are connected with a low pressure source 20 through check valves 21, 22 as well as with a tank through selector valves 25, 26. Since this allows operation of two capacity controlling actuators 12, 13 by low pressure fluid from the low pressure source 20, capacity control may be performed without reducing the efficiency of a pump-motor as well as using another subsidiary pump which causes a power waste.
COPYRIGHT: (C)1981,JPO&Japio
JP4048080A 1980-03-31 1980-03-31 Controller of variable capacity pump-motor Granted JPS56138477A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP4048080A JPS56138477A (en) 1980-03-31 1980-03-31 Controller of variable capacity pump-motor

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP4048080A JPS56138477A (en) 1980-03-31 1980-03-31 Controller of variable capacity pump-motor

Publications (2)

Publication Number Publication Date
JPS56138477A true JPS56138477A (en) 1981-10-29
JPS646346B2 JPS646346B2 (en) 1989-02-02

Family

ID=12581766

Family Applications (1)

Application Number Title Priority Date Filing Date
JP4048080A Granted JPS56138477A (en) 1980-03-31 1980-03-31 Controller of variable capacity pump-motor

Country Status (1)

Country Link
JP (1) JPS56138477A (en)

Also Published As

Publication number Publication date
JPS646346B2 (en) 1989-02-02

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