JPS5715103A - Falloff preventive circuit for liquid pressure cylinder - Google Patents

Falloff preventive circuit for liquid pressure cylinder

Info

Publication number
JPS5715103A
JPS5715103A JP8772280A JP8772280A JPS5715103A JP S5715103 A JPS5715103 A JP S5715103A JP 8772280 A JP8772280 A JP 8772280A JP 8772280 A JP8772280 A JP 8772280A JP S5715103 A JPS5715103 A JP S5715103A
Authority
JP
Japan
Prior art keywords
selector valve
speed sensor
preset value
output
stop position
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.)
Pending
Application number
JP8772280A
Other languages
Japanese (ja)
Inventor
Shuichi Ichiyama
Masaki Kanehara
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 JP8772280A priority Critical patent/JPS5715103A/en
Publication of JPS5715103A publication Critical patent/JPS5715103A/en
Pending legal-status Critical Current

Links

Landscapes

  • Fluid-Pressure Circuits (AREA)

Abstract

PURPOSE: To prevent unrestrained fall of a liquid pressure cylinder at the rupture time of pipings of an oil-hydraulic shovel etc. by providing a selector valve and a speed sensor on the exhaust side at the unrestrained falling time of the cylinder and by arranging so that the selector valve is set to the stop position when the output of the speed sensor exceed a certain preset value.
CONSTITUTION: A selector valve with detent, 8, is arranged in a pipeline 5, and a speed sensor composed of a stroke gauge 10 to sense the stroke and a differential operator 11 is provided, where the selector valve 8 is held in the operation position normally and changed over to the stop position when the output of the differential operator 11 exceeds a certain preset value. Thereby, even rupture of the line 5 will not lead to unrestrained fall of the oil-hydraulic cylinder 2 because the selector valve 8 is changed over to the stop position when the output of the differential operator 11 exceeds the preset value. Not even hunting will occur because no counterbalance valve is used.
COPYRIGHT: (C)1982,JPO&Japio
JP8772280A 1980-06-30 1980-06-30 Falloff preventive circuit for liquid pressure cylinder Pending JPS5715103A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP8772280A JPS5715103A (en) 1980-06-30 1980-06-30 Falloff preventive circuit for liquid pressure cylinder

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP8772280A JPS5715103A (en) 1980-06-30 1980-06-30 Falloff preventive circuit for liquid pressure cylinder

Publications (1)

Publication Number Publication Date
JPS5715103A true JPS5715103A (en) 1982-01-26

Family

ID=13922795

Family Applications (1)

Application Number Title Priority Date Filing Date
JP8772280A Pending JPS5715103A (en) 1980-06-30 1980-06-30 Falloff preventive circuit for liquid pressure cylinder

Country Status (1)

Country Link
JP (1) JPS5715103A (en)

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6131705A (en) * 1984-07-20 1986-02-14 Kayaba Ind Co Ltd Control device of counterbalance valve
JPS6131704A (en) * 1984-07-20 1986-02-14 Kayaba Ind Co Ltd Control device of counterbalance valve
JPS6138201A (en) * 1984-07-31 1986-02-24 Kayaba Ind Co Ltd Control device for counterbalance valve
JPS6182009A (en) * 1984-09-21 1986-04-25 Kayaba Ind Co Ltd Controller of counterbalance valve
US8245446B2 (en) 2009-06-23 2012-08-21 Hp Doors, Llc Tilt-up door
US9091107B2 (en) 2009-06-23 2015-07-28 Hp Doors, Llc Tilt-up door
US9428951B2 (en) 2009-06-23 2016-08-30 Hp Doors, Llc Tilt-up door
US9631418B2 (en) 2014-06-25 2017-04-25 Phillip A. Crown Hydraulically operated overhead tilt-up door with stabilizer
US10208529B2 (en) 2009-06-23 2019-02-19 Higher Power Hydraulic Doors, Llc Tilt-up door

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6131705A (en) * 1984-07-20 1986-02-14 Kayaba Ind Co Ltd Control device of counterbalance valve
JPS6131704A (en) * 1984-07-20 1986-02-14 Kayaba Ind Co Ltd Control device of counterbalance valve
JPH0456886B2 (en) * 1984-07-20 1992-09-09 Kayaba Industry Co Ltd
JPH0456885B2 (en) * 1984-07-20 1992-09-09 Kayaba Industry Co Ltd
JPS6138201A (en) * 1984-07-31 1986-02-24 Kayaba Ind Co Ltd Control device for counterbalance valve
JPS6182009A (en) * 1984-09-21 1986-04-25 Kayaba Ind Co Ltd Controller of counterbalance valve
US8245446B2 (en) 2009-06-23 2012-08-21 Hp Doors, Llc Tilt-up door
US8539716B2 (en) 2009-06-23 2013-09-24 Hp Doors, Llc Tilt-up door
US8769871B2 (en) 2009-06-23 2014-07-08 Hp Doors, Llc Tilt-up door
US9015996B2 (en) 2009-06-23 2015-04-28 Hp Doors, Llc Tilt-up door
US9091107B2 (en) 2009-06-23 2015-07-28 Hp Doors, Llc Tilt-up door
US9404301B2 (en) 2009-06-23 2016-08-02 Hp Doors, Llc Tilt-up door
US9428951B2 (en) 2009-06-23 2016-08-30 Hp Doors, Llc Tilt-up door
US10208529B2 (en) 2009-06-23 2019-02-19 Higher Power Hydraulic Doors, Llc Tilt-up door
US9631418B2 (en) 2014-06-25 2017-04-25 Phillip A. Crown Hydraulically operated overhead tilt-up door with stabilizer

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