GB890644A - Improvements in or relating to hydraulic jacks, pit props or the like - Google Patents

Improvements in or relating to hydraulic jacks, pit props or the like

Info

Publication number
GB890644A
GB890644A GB1832157A GB1832157A GB890644A GB 890644 A GB890644 A GB 890644A GB 1832157 A GB1832157 A GB 1832157A GB 1832157 A GB1832157 A GB 1832157A GB 890644 A GB890644 A GB 890644A
Authority
GB
United Kingdom
Prior art keywords
prop
piston
main cylinder
cylinder
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
GB1832157A
Inventor
Frank Cowlishaw
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.)
Dobson Ltd W E & F
WE&F Dobson Ltd
Original Assignee
Dobson Ltd W E & F
WE&F Dobson 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
Priority to BE568439D priority Critical patent/BE568439A/xx
Application filed by Dobson Ltd W E & F, WE&F Dobson Ltd filed Critical Dobson Ltd W E & F
Priority to GB1832157A priority patent/GB890644A/en
Priority to DED28261A priority patent/DE1211113B/en
Priority to FR1207456D priority patent/FR1207456A/en
Publication of GB890644A publication Critical patent/GB890644A/en
Expired legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B66—HOISTING; LIFTING; HAULING
    • B66F—HOISTING, LIFTING, HAULING OR PUSHING, NOT OTHERWISE PROVIDED FOR, e.g. DEVICES WHICH APPLY A LIFTING OR PUSHING FORCE DIRECTLY TO THE SURFACE OF A LOAD
    • B66F3/00—Devices, e.g. jacks, adapted for uninterrupted lifting of loads
    • B66F3/24—Devices, e.g. jacks, adapted for uninterrupted lifting of loads fluid-pressure operated
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
    • E21D15/00—Props; Chocks, e.g. made of flexible containers filled with backfilling material
    • E21D15/14—Telescopic props
    • E21D15/44—Hydraulic, pneumatic, or hydraulic-pneumatic props
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
    • E21D23/00—Mine roof supports for step- by- step movement, e.g. in combination with provisions for shifting of conveyors, mining machines, or guides therefor
    • E21D23/006—Mine roof supports for step- by- step movement, e.g. in combination with provisions for shifting of conveyors, mining machines, or guides therefor provided with essential hydraulic devices
    • E21D23/0069—Mine roof supports for step- by- step movement, e.g. in combination with provisions for shifting of conveyors, mining machines, or guides therefor provided with essential hydraulic devices without essential advancing shifting devices
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
    • E21D23/00—Mine roof supports for step- by- step movement, e.g. in combination with provisions for shifting of conveyors, mining machines, or guides therefor
    • E21D23/006—Mine roof supports for step- by- step movement, e.g. in combination with provisions for shifting of conveyors, mining machines, or guides therefor provided with essential hydraulic devices
    • E21D23/0073—Mine roof supports for step- by- step movement, e.g. in combination with provisions for shifting of conveyors, mining machines, or guides therefor provided with essential hydraulic devices with advancing shifting devices connected therewith

Landscapes

  • Engineering & Computer Science (AREA)
  • Mining & Mineral Resources (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Geology (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Mechanical Engineering (AREA)
  • Structural Engineering (AREA)
  • Fluid-Driven Valves (AREA)
  • Supply Devices, Intensifiers, Converters, And Telemotors (AREA)
  • Shaping Metal By Deep-Drawing, Or The Like (AREA)

Abstract

890,644. Hydraulic pit props. DOBSON Ltd., W. E. & F. May 29, 1958 [June 11, 1957], No. 18321/57. Class 20(2) A hydraulic pit prop comprises hydraulic pressure intensifier means 21, 22, 25 which preloads the prop. To extend the prop, hydraulic fluid is introduced at a valve 11 to the main cylinder formed by the outer prop part, to act on the piston 15, and at 32 to an auxiliary cylinder in the inner prop part 2 to act on the piston 22 of the pressure intensifier means and the head 13 of the prop. When inner prop part 2 bears on the roof, valve 11 closes and the pressure in the main cylinder is increased by fluid in the auxiliary cylinder acting on the unit 21, 22 which has a smaller piston head 25 moving in a cylinder 26 in communication, via a bore 27, with the main cylinder. The intensifier means is initially urged into the state of equilibrium as shown by expelling air from the main cylinder through a manually and externally adjusted apertured control screw 20 and ports 15a, 28a communicating with the underside of the piston 22. A cam operated external valve control (Figs. 2-5, not shown, refer) collapses the prop by allowing fluid to escape at 32 and 12. Specifications 854,967, 856,719, 856,720 and 885,293 are referred to.
GB1832157A 1957-06-11 1957-06-11 Improvements in or relating to hydraulic jacks, pit props or the like Expired GB890644A (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
BE568439D BE568439A (en) 1957-06-11
GB1832157A GB890644A (en) 1957-06-11 1957-06-11 Improvements in or relating to hydraulic jacks, pit props or the like
DED28261A DE1211113B (en) 1957-06-11 1958-06-07 Hydraulic pit ram
FR1207456D FR1207456A (en) 1957-06-11 1958-06-11 Improvements relating to hydraulic rams and the like

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB1832157A GB890644A (en) 1957-06-11 1957-06-11 Improvements in or relating to hydraulic jacks, pit props or the like

Publications (1)

Publication Number Publication Date
GB890644A true GB890644A (en) 1962-03-07

Family

ID=10110475

Family Applications (1)

Application Number Title Priority Date Filing Date
GB1832157A Expired GB890644A (en) 1957-06-11 1957-06-11 Improvements in or relating to hydraulic jacks, pit props or the like

Country Status (4)

Country Link
BE (1) BE568439A (en)
DE (1) DE1211113B (en)
FR (1) FR1207456A (en)
GB (1) GB890644A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108862088A (en) * 2018-08-21 2018-11-23 九江消防装备有限公司 A kind of electronic jacking machine

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5275086A (en) * 1992-08-27 1994-01-04 Unlimited Solutions, Inc. Fluid actuator with internal pressure relief valve

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE808785C (en) * 1948-10-02 1951-07-19 Hermann Wolf G M B H Method and mold for the production of plastic moldings with inserts made of metal or the like, for example eyeglass hook brackets made of thermoplastics with a wire insert
DE871585C (en) * 1950-01-17 1953-03-23 Edgar Tacke Hydraulic pit ram
DE918562C (en) * 1951-11-24 1954-09-30 Werner Sogalla Dr Ing Hydraulic pit ram
LU34334A1 (en) * 1955-04-25

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108862088A (en) * 2018-08-21 2018-11-23 九江消防装备有限公司 A kind of electronic jacking machine
CN108862088B (en) * 2018-08-21 2023-07-18 九江消防装备有限公司 Electric propping device

Also Published As

Publication number Publication date
BE568439A (en)
FR1207456A (en) 1960-02-17
DE1211113B (en) 1966-02-24

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