GB825000A - An improved hydraulic jack or strut device - Google Patents

An improved hydraulic jack or strut device

Info

Publication number
GB825000A
GB825000A GB1466457A GB1466457A GB825000A GB 825000 A GB825000 A GB 825000A GB 1466457 A GB1466457 A GB 1466457A GB 1466457 A GB1466457 A GB 1466457A GB 825000 A GB825000 A GB 825000A
Authority
GB
United Kingdom
Prior art keywords
jack
valves
hydraulic jack
lifted
improved hydraulic
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.)
Expired
Application number
GB1466457A
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.)
JOHN WILLIAM GRAY CAMPBELL
Original Assignee
JOHN WILLIAM GRAY CAMPBELL
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 JOHN WILLIAM GRAY CAMPBELL filed Critical JOHN WILLIAM GRAY CAMPBELL
Priority to GB1466457A priority Critical patent/GB825000A/en
Publication of GB825000A publication Critical patent/GB825000A/en
Expired legal-status Critical Current

Links

Classifications

    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21C—MINING OR QUARRYING
    • E21C35/00—Details of, or accessories for, machines for slitting or completely freeing the mineral from the seam, not provided for in groups E21C25/00 - E21C33/00, E21C37/00 or E21C39/00
    • E21C35/08—Guiding the machine
    • E21C35/12—Guiding the machine along a conveyor for the cut material
    • E21C35/14—Equipment for pressing the conveyor towards the working face

Landscapes

  • Engineering & Computer Science (AREA)
  • Mining & Mineral Resources (AREA)
  • Mechanical Engineering (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Geology (AREA)
  • Quick-Acting Or Multi-Walled Pipe Joints (AREA)

Abstract

825,000. Hydraulic jacks. CAMPBELL, J. W. G. April 3, 1958 [May 8, 1957], No. 14664/57. Class 69 (2). [Also in Group XXX] An hydraulic jack is controlled by four valves contained in one of the jack cylinder heads, which are actuated in pairs for extension and retraction of the jack. Each valve consists of a ball 5 which is lifted from its seat when mushroom head 7 is pushed inwards by rotatable cam surface 10. Liquid is introduced via port 1a and non-return valve 39, and depending on which pair of valves is lifted, passes to one side of the jack piston, liquid simultaneously being exhausted from the other. When the jack is in the required position, the valves are closed. A relief valve (not shown) is provided to prevent excessive pressures.
GB1466457A 1957-05-08 1957-05-08 An improved hydraulic jack or strut device Expired GB825000A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB1466457A GB825000A (en) 1957-05-08 1957-05-08 An improved hydraulic jack or strut device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB1466457A GB825000A (en) 1957-05-08 1957-05-08 An improved hydraulic jack or strut device

Publications (1)

Publication Number Publication Date
GB825000A true GB825000A (en) 1959-12-09

Family

ID=10045356

Family Applications (1)

Application Number Title Priority Date Filing Date
GB1466457A Expired GB825000A (en) 1957-05-08 1957-05-08 An improved hydraulic jack or strut device

Country Status (1)

Country Link
GB (1) GB825000A (en)

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