GB636568A - Improvements in pit props and other telescopic struts - Google Patents

Improvements in pit props and other telescopic struts

Info

Publication number
GB636568A
GB636568A GB92548A GB92548A GB636568A GB 636568 A GB636568 A GB 636568A GB 92548 A GB92548 A GB 92548A GB 92548 A GB92548 A GB 92548A GB 636568 A GB636568 A GB 636568A
Authority
GB
United Kingdom
Prior art keywords
ram
cylinder
blows
valve
prop
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
GB92548A
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.)
Individual
Original Assignee
Individual
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 BE486663D priority Critical patent/BE486663A/xx
Application filed by Individual filed Critical Individual
Priority to US58949A priority patent/US2621631A/en
Priority to NL143867A priority patent/NL76043C/xx
Priority to DEP25763A priority patent/DE808225C/en
Priority to FR978701D priority patent/FR978701A/en
Publication of GB636568A publication Critical patent/GB636568A/en
Priority to FR69104D priority patent/FR69104E/en
Expired legal-status Critical Current

Links

Classifications

    • E—FIXED CONSTRUCTIONS
    • E21—EARTH DRILLING; MINING
    • E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
    • E21D15/00—Props; Chocks, e.g. made of flexible containers filled with backfilling material
    • E21D15/60—Devices for withdrawing props or chocks
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH 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
    • E21D15/45—Hydraulic, pneumatic, or hydraulic-pneumatic props having closed fluid system, e.g. with built-in pumps or accumulators

Abstract

636,568. Hydraulic pit-props. DOWTY, G. H. Jan. 12, 1948, No. 925. [Class 20 (ii)] [Also in Group XXX] A hydraulic pit-prop having a ram 1 which forms a reservoir for the actuating fluid, the ram being raised by pumping this fluid by a pump 8, into the cylinder 3, comprises a relief valve 20 which is contained in a casing 15 at the outer end of the ram 1 and controls the pressure in the cylinder 3 through a pipe 19 and is adapted to be unseated by a connection 25, 26, 27 and a link 30 in order to allow the prop to contract. The external control member 27 is protected from blows by an extension of the casing 15 and lost motion between the members 25, 26 prevents these blows being transmitted to the valve 20. A valve 31 admits air to the ram 1 as the actuating fluid is withdrawn. The pump 8 is operated by a crank 11.The cylinder 3 is protected from blows by an outer cylinder 37 or a rubber covering.
GB92548A 1948-01-12 1948-01-12 Improvements in pit props and other telescopic struts Expired GB636568A (en)

Priority Applications (6)

Application Number Priority Date Filing Date Title
BE486663D BE486663A (en) 1948-01-12
US58949A US2621631A (en) 1948-01-12 1948-11-08 Telescopic hydraulic mine roof support
NL143867A NL76043C (en) 1948-01-12 1948-12-15
DEP25763A DE808225C (en) 1948-01-12 1948-12-20 Pit stamp
FR978701D FR978701A (en) 1948-01-12 1949-04-05 forestay or prop
FR69104D FR69104E (en) 1948-01-12 1954-07-20 forestay or prop

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB2011253A GB726384A (en) 1953-07-20 1953-07-20 Improvements in pit props and other telescopic struts

Publications (1)

Publication Number Publication Date
GB636568A true GB636568A (en) 1950-05-03

Family

ID=10140587

Family Applications (2)

Application Number Title Priority Date Filing Date
GB92548A Expired GB636568A (en) 1948-01-12 1948-01-12 Improvements in pit props and other telescopic struts
GB2011253A Expired GB726384A (en) 1948-01-12 1953-07-20 Improvements in pit props and other telescopic struts

Family Applications After (1)

Application Number Title Priority Date Filing Date
GB2011253A Expired GB726384A (en) 1948-01-12 1953-07-20 Improvements in pit props and other telescopic struts

Country Status (1)

Country Link
GB (2) GB636568A (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2816728A (en) * 1949-04-07 1957-12-17 Lobbe Armin Dieter Hydraulic pit props
US2830563A (en) * 1954-03-26 1958-04-15 Burton B Burckhalter Automatic jack leg
US2857125A (en) * 1953-02-25 1958-10-21 Dowty Hydraulic Units Ltd Mine roof supports
CN112727481A (en) * 2021-02-05 2021-04-30 中铁工程装备集团有限公司 Excavation cabin direct discharge slurry shield machine and excavation cabin direct discharge slurry method

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BE548513A (en) * 1955-06-10
DE1171382B (en) * 1960-02-23 1964-06-04 H Joe Rheinbay Dipl Ing Hydraulic pit ram
DE1206830B (en) * 1962-08-27 1965-12-16 Bochumer Eisen Heintzmann Hydraulic pit ram

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2816728A (en) * 1949-04-07 1957-12-17 Lobbe Armin Dieter Hydraulic pit props
US2857125A (en) * 1953-02-25 1958-10-21 Dowty Hydraulic Units Ltd Mine roof supports
US2830563A (en) * 1954-03-26 1958-04-15 Burton B Burckhalter Automatic jack leg
CN112727481A (en) * 2021-02-05 2021-04-30 中铁工程装备集团有限公司 Excavation cabin direct discharge slurry shield machine and excavation cabin direct discharge slurry method

Also Published As

Publication number Publication date
GB726384A (en) 1955-03-16

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