US3656411A - Telescopic props - Google Patents

Telescopic props Download PDF

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Publication number
US3656411A
US3656411A US865355A US3656411DA US3656411A US 3656411 A US3656411 A US 3656411A US 865355 A US865355 A US 865355A US 3656411D A US3656411D A US 3656411DA US 3656411 A US3656411 A US 3656411A
Authority
US
United States
Prior art keywords
chamber
inner member
piston
disposed
pressure fluid
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 - Lifetime
Application number
US865355A
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English (en)
Inventor
Karl Heinz Plester
Heinz Hessel
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.)
Gewerkschaft Eisenhutte Westfalia GmbH
Original Assignee
Gewerkschaft Eisenhutte Westfalia GmbH
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 claimed from DE19691931627 external-priority patent/DE1931627C3/de
Application filed by Gewerkschaft Eisenhutte Westfalia GmbH filed Critical Gewerkschaft Eisenhutte Westfalia GmbH
Application granted granted Critical
Publication of US3656411A publication Critical patent/US3656411A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B15/00—Fluid-actuated devices for displacing a member from one position to another; Gearing associated therewith
    • F15B15/08—Characterised by the construction of the motor unit
    • F15B15/14—Characterised by the construction of the motor unit of the straight-cylinder type
    • F15B15/16—Characterised by the construction of the motor unit of the straight-cylinder type of the telescopic type
    • 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

Definitions

  • ABSTRACT A telescopic prop with an outer member and first and second concentric inner members which inner members are disposed within. said outer member and are longitudinally displaceable.
  • the first inner member is extendable and retractable hydraulically whereas the second inner member is extendable hydraulically but retractable nonhydraulically.
  • Each inner member has a piston facing a chamber chargeable with hydraulic pressure fluid and two spring-biased non-return valves are operably disposed between the chambers, one valve opening in a direction between the chamber associated with the piston of the first inner member and the chamber associated with the piston of the second inner member and the other valve opening in the opposite direction.
  • Telescopic props which have an outer member within which is disposed two concentric inner members extendable and retractable relative to the outer member.
  • the first inner member disposed between the outer member and the second inner member, has a piston provided with a bore to allow pressure fluid to act on a piston of the second inner member. Pressure fluid flows through this bore when the first inner member has been moved fully outwards to thereby move the second inner member outwards until the prop is secured in the desired manner.
  • the second inner member is only able to move outwards by a certain amount.
  • the first inner member In the process of retraction, the first inner member is retracted hydraulically and a rising pressure will form underneath the piston of the first inner member. This pressure is transmitted through the bore in the piston to act upon the piston of the second inner member. Thus, as the first inner member is being retracted the second inner member is being extended. For this reason the complete retraction of the prop cannot be effected until sufficient time has elapsed to allow the second inner member to move inwards under its own weight or to allow the second member to be moved inwards by additional mechanical devices.
  • a general object of this invention is to overcome the aforementioned disadvantage and in particular to ensure that the second inner member will not move outwards when the first inner member is being retracted.
  • a first piston formed at the inner end of the first inner member, a second piston formed at the inner end of the second inner member f. a first chamber chargeable with hydraulic pressure fluid and disposed between said outer member and said first piston,
  • a first spring-biased non-return valve operably disposed to open in'a direction from the first chamber to the second chamber
  • a second spring-biased non-return valve operably disposed to open in a direction form the second chamber to the first chamber.
  • the spring force of the first valve is greater than the spring force of the second valve.
  • the valves are preferably disposed in a housing carried by the first piston.
  • the second piston is then recessed to receive the housing when the first and second pistons are disposed adjacent one another,
  • FIG. 1 is a vertical section through a telescopic prop made in accordance with the invention.
  • FIG. 2 is a view corresponding to FIG. 1, but on a larger scale showing the piston of the first inner member and the construction of the non-return valves.
  • a hydraulically operated telescopic prop has a cylindrical outer member 12 within which is disposed a first cylindrical inner member 3.
  • a second inner member 2 is in turn disposed within the member 3.
  • An annular chamber 13 is provided between the inner member 3 and the outer member and is used in an operation known as robbing.
  • the inner member 3 is provided with a piston 4 at its innermost end and the piston 4 is formed with a housing 10 containing non-return valves 5, 6.
  • the lower end of the member 12 is provided with a base and a chamber ,8 is formed between the base and the piston 4.
  • a bore 14 is provided in the base to allow the chamber 8 to be charged with hydraulic pressure fluid.
  • the member 2 likewise has a piston 9 at its innermost end and a chamber 7 is provided between the pistons 4, 9.
  • a recess 11 in the piston 9 can receive the valve housing 10 when the pistons 4, 9 lie adjacent one another.
  • FIG. 2 shows the construction of the non-return valves 5, 6 which are of conventional design.
  • the valve 6 has a valve element in the form of a ball 15 which is urged by a compression spring against a seating 16.
  • the valve 5 has a valve element in the form of a ball 18 which is urged against a seating 19 by means of a plunger acted upon by a compression spring 17.
  • the force of thespring 17 is greater than that of the spring of the valve 6.
  • the valves 5, 6 act in opposition to one another with the valve 5 opening in the direction from chamber 8 to chamber 7 and the valve 6 opening in the direction from chamber 7 to chamber 8.
  • the valve 6 also remains closed when the member 3 is being retracted and only opens after the termination of this process, when there is no longer any pressure in the chamber 8 underneath the piston 4 to allow relief of any pressure in chamber 7. At this stage when the member 3 is fully retracted the weight of the member 2 causes the pressure in the chamber 7 to lift the ball 15 from its seating 16. When the valve 6 opens the inner member 2 can thus retract under its own weight or alternatively mechanical auxiliary devices can be utilized to retract the member 2 more quickly.
  • said prop comprising:
  • a second inner member disposed within said first inner member and mounted for longitudinal displacement relative thereto.
  • a first piston formed at the inner end of the first inner member; said first piston including only two passages capable of receiving valves;
  • a first spring-biased non-return valve operably disposed in one of said two passages and between the first and second chambers and adapted to open in a direction from the first chamber to the second chamber when the first inner member has been fully extended to allow pressure fluid to enter the second chamber and extend the second inner member beyond the first inner member;
  • a second spring-biased non-return valve operably disposed in the other of said two passages and between the first and second chambers and adapted to open in a direction from the second chamber to the first chamber when the first inner member has been fully retracted to permit pressure fluid to be discharged from the second chamber to allow the second inner member to retract;
  • first and second valves being disposed in a single housing carried by the first piston and the second piston is provided with a recess which can receive said housing when the first and second pistons are brought together.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mining & Mineral Resources (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Geology (AREA)
  • Structural Engineering (AREA)
  • Fluid Mechanics (AREA)
  • General Engineering & Computer Science (AREA)
  • Actuator (AREA)
  • Lining And Supports For Tunnels (AREA)
  • Check Valves (AREA)
  • Fluid-Damping Devices (AREA)
  • Reciprocating Pumps (AREA)
US865355A 1969-06-21 1969-10-10 Telescopic props Expired - Lifetime US3656411A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE19691931627 DE1931627C3 (de) 1969-06-21 Hydraulischer Teleskopstempel

Publications (1)

Publication Number Publication Date
US3656411A true US3656411A (en) 1972-04-18

Family

ID=5737686

Family Applications (1)

Application Number Title Priority Date Filing Date
US865355A Expired - Lifetime US3656411A (en) 1969-06-21 1969-10-10 Telescopic props

Country Status (4)

Country Link
US (1) US3656411A (enrdf_load_stackoverflow)
JP (1) JPS4923441B1 (enrdf_load_stackoverflow)
FR (1) FR2030920A5 (enrdf_load_stackoverflow)
GB (1) GB1280899A (enrdf_load_stackoverflow)

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3760704A (en) * 1971-12-30 1973-09-25 Polaroid Corp Reflex camera and viewer with a folded optical path
US3961559A (en) * 1974-11-18 1976-06-08 Hiroshi Teramachi Actuator
US4516468A (en) * 1983-01-10 1985-05-14 Hydraulic Technology Corporation Double acting telescopic cylinder construction
US5209154A (en) * 1990-11-08 1993-05-11 Allied-Signal Inc. Dual area brake actuation piston mechanism
US5927178A (en) * 1997-11-24 1999-07-27 Diebolt International, Inc. Press driven tool actuator module
US5953967A (en) * 1996-05-28 1999-09-21 Junkers; John Fluid-operated cylinder-piston unit, and a tool provided therewith
US6463841B2 (en) * 2000-10-10 2002-10-15 Kayaba Kogyo Kabushiki Kaisha Lift cylinder
EP1260479A3 (en) * 2001-05-24 2003-10-22 The Raymond Corporation Cushioned actuator
CN101105133B (zh) * 2007-07-27 2010-05-19 中国矿业大学 双伸缩悬浮式液压立柱
CN101984220A (zh) * 2010-05-28 2011-03-09 金湖小青青机电设备有限公司 双伸缩悬浮液压立柱
CN105020197A (zh) * 2015-07-24 2015-11-04 芜湖市银鸿液压件有限公司 复合式双向液压起升坝油缸及其使用方法

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5293669U (enrdf_load_stackoverflow) * 1976-01-12 1977-07-13
JPS56160449U (enrdf_load_stackoverflow) * 1980-04-30 1981-11-30
JPS6143865U (ja) * 1984-08-23 1986-03-22 東一郎 柴山 植木鉢

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2172117A (en) * 1938-05-02 1939-09-05 John M Beaufort Radio antenna
US2378409A (en) * 1942-03-18 1945-06-19 Joseph F Joy Hydraulic elevating mechanism
US2517153A (en) * 1946-08-16 1950-08-01 Gar Wood Ind Inc Telescopic power down hoist
US2813515A (en) * 1955-04-28 1957-11-19 Joy Mfg Co Telescopic uniform pressure providing apparatus
US3252680A (en) * 1962-08-21 1966-05-24 Electro Hydraulics Ltd Roof supports
US3426649A (en) * 1963-11-29 1969-02-11 Rheinstahl Wanheim Gmbh Multistage hydraulic mine prop

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2172117A (en) * 1938-05-02 1939-09-05 John M Beaufort Radio antenna
US2378409A (en) * 1942-03-18 1945-06-19 Joseph F Joy Hydraulic elevating mechanism
US2517153A (en) * 1946-08-16 1950-08-01 Gar Wood Ind Inc Telescopic power down hoist
US2813515A (en) * 1955-04-28 1957-11-19 Joy Mfg Co Telescopic uniform pressure providing apparatus
US3252680A (en) * 1962-08-21 1966-05-24 Electro Hydraulics Ltd Roof supports
US3426649A (en) * 1963-11-29 1969-02-11 Rheinstahl Wanheim Gmbh Multistage hydraulic mine prop

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3760704A (en) * 1971-12-30 1973-09-25 Polaroid Corp Reflex camera and viewer with a folded optical path
US3961559A (en) * 1974-11-18 1976-06-08 Hiroshi Teramachi Actuator
US4516468A (en) * 1983-01-10 1985-05-14 Hydraulic Technology Corporation Double acting telescopic cylinder construction
US5209154A (en) * 1990-11-08 1993-05-11 Allied-Signal Inc. Dual area brake actuation piston mechanism
US5953967A (en) * 1996-05-28 1999-09-21 Junkers; John Fluid-operated cylinder-piston unit, and a tool provided therewith
US5927178A (en) * 1997-11-24 1999-07-27 Diebolt International, Inc. Press driven tool actuator module
US6463841B2 (en) * 2000-10-10 2002-10-15 Kayaba Kogyo Kabushiki Kaisha Lift cylinder
EP1260479A3 (en) * 2001-05-24 2003-10-22 The Raymond Corporation Cushioned actuator
CN101105133B (zh) * 2007-07-27 2010-05-19 中国矿业大学 双伸缩悬浮式液压立柱
CN101984220A (zh) * 2010-05-28 2011-03-09 金湖小青青机电设备有限公司 双伸缩悬浮液压立柱
CN105020197A (zh) * 2015-07-24 2015-11-04 芜湖市银鸿液压件有限公司 复合式双向液压起升坝油缸及其使用方法

Also Published As

Publication number Publication date
DE1931627B2 (de) 1977-06-30
DE1931627A1 (de) 1971-01-07
FR2030920A5 (enrdf_load_stackoverflow) 1970-11-13
GB1280899A (en) 1972-07-05
JPS4923441B1 (enrdf_load_stackoverflow) 1974-06-15

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