GB2096223A - Improvements in hydraulic control apparatus for controlling the operation of mine roof support props - Google Patents

Improvements in hydraulic control apparatus for controlling the operation of mine roof support props Download PDF

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Publication number
GB2096223A
GB2096223A GB8215240A GB8215240A GB2096223A GB 2096223 A GB2096223 A GB 2096223A GB 8215240 A GB8215240 A GB 8215240A GB 8215240 A GB8215240 A GB 8215240A GB 2096223 A GB2096223 A GB 2096223A
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GB
United Kingdom
Prior art keywords
pressure
prop
valve device
chamber
piston member
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.)
Granted
Application number
GB8215240A
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GB2096223B (en
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
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Gewerkschaft Eisenhutte Westfalia GmbH
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Publication of GB2096223A publication Critical patent/GB2096223A/en
Application granted granted Critical
Publication of GB2096223B publication Critical patent/GB2096223B/en
Expired legal-status Critical Current

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Classifications

    • EFIXED CONSTRUCTIONS
    • E21EARTH OR ROCK DRILLING; MINING
    • E21DSHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
    • E21D23/00Mine roof supports for step- by- step movement, e.g. in combination with provisions for shifting of conveyors, mining machines, or guides therefor
    • E21D23/16Hydraulic or pneumatic features, e.g. circuits, arrangement or adaptation of valves, setting or retracting devices
    • E21D23/26Hydraulic or pneumatic control
    • EFIXED CONSTRUCTIONS
    • E21EARTH OR ROCK DRILLING; MINING
    • E21DSHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
    • E21D23/00Mine roof supports for step- by- step movement, e.g. in combination with provisions for shifting of conveyors, mining machines, or guides therefor
    • E21D23/16Hydraulic or pneumatic features, e.g. circuits, arrangement or adaptation of valves, setting or retracting devices

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  • Engineering & Computer Science (AREA)
  • Mining & Mineral Resources (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Geology (AREA)
  • Safety Valves (AREA)
  • Fluid-Pressure Circuits (AREA)
  • Control Of Presses (AREA)

Abstract

Hydraulic control apparatus serves to operate roof support props of a mineral mining installation and employs a manually-operable main valve device 11 which can be set to various positions to selectively connect fluid pressure and return lines P, R to the working chambers 10@1<1>, 10@1<2> of at least one associated prop 10 to thereby cause extension and retraction of the prop. A pressure- relief valve device 12 is connected to the particular prop chamber 10@1<1> charged with pressure fluid by the main valve device 11 to effect extension of the prop. The relief valve device 12 is automatically set by pressure control means 11, 42, 41, 40, 39 to respond to a significantly higher pressure whilst the prop 10 is actually being extended (state 1) and set by the main device 11 and reverts back to its normal response pressure once the prop 10 is set (state 0). <IMAGE>

Description

1 GB 2 096 223 A 1 SPECRCATION Improvements in hydraulic control apparatus
for controlling the operation of mine roof support props The present invention relates to hydraulic 70 control apparatus for operating the support props of a mineral mining installation.
Control apparatus is described in published German patent specification P27 49 312.5 which utilizes manual-operable control valves which serve to connect pressure fluid feed and return lines selectively to the working chambers of associated props. The apparatus employs an automatic setting arrangement composed of valve devices. This arrangement automatically connects the prop chambers, charged with fluid to extend the props, to the pressure line once a threshold pressure is exceeded. This ensures the props can be properly set against the roof even if one of the control valves is operated prematurely to disconnect the pressure line to an associated prop chamber. The automatic setting arrangement isolates the prop chambers from the pressure line once the setting pressure is reached. Excessive pressure is prevented from building up in the prop chambers by means of pressure-relief valves set to respond at pressure above the normal setting pressure. The threshold pressure level at which the setting arrangement comes into operation is higher than that present in the prop chambers when the props are being extended freely without contact with the roof and less than the setting pressure. The threshold pressure is selected so that any prop can be extended and retracted by operation of the associated control valve freely and the prop can be extended until its roof cap or the like actually contacts the roof without the setting arrangement coming into action. This enables repair and maintenance work, and any back filling necessary in the event of roof fails, to be performed without the automatic setting arrangement becoming affected. Generally the threshold pressure at which the setting arrangement comes into operation is in the range 50 bars to 150 bars while the pressure in the pressure line is significantly higher -typically above 300 bars and in the range 350 bars to 450 bars.
A general objectof the present invention is to provide improved control apparatus for operating the support props of a mining installation.
Apparatus constructed in accordance with the invention comprises a control valve device for selectively connecting first and second working chambers of an associated support prop to 120 pressure fluid feed and retun lines to effect extension and retraction of the props and a pressure-relief valve device which is connected to the first working chamber of the prop which is charged with pressure fluid by the control valve device when the prop is to be extended and set, said relief valve device being connectible to the return line to prevent excessive pressure in the first chamber and control means which automatically changes the response pressure of the relief valve device so that the response pressure of the relief valve device is higher when the associated prop is being extended and set than it is when the prop has become set.
Control apparatus constructed in accordance with the invention can utilize a manually-operable control valve device which can be set with a lever to various positions to connect the chambers of an associated roof support prop to the pressure fluid feed and return lines to effect extension and retraction of the prop in a manner known per se. Preferably the control valve device has the socalled -dead-man's handle" mechanism which causes the device to adopt a neutral position when its lever is released to isolate the pressure line from the prop pressure chamber which is used to extend the prop. The pressure-relief valve device is connected to the prop pressure chamber to prevent excessive pressure building up in the neutral position.
The pressure-relief valve can be based on that described in German published Patent Specifications 1750834 and 2803283.
The pressure control means makes the response pressure of the relief valve device significantly higher while the setting operation actually takes place. Once the associated prop has become set however, the pressure control permits the relief valve device to revert back to its normal response pressure.
The relief valve device with the pressure control facility can employ a spring-loaded piston member sliding in a guide piece provided with a mating O-ring seal. A housing, accommodating the guide piece and its piston member, may have a chamber which is connected to the pressure line when the prop is being set. The resulting pressure in the housing chamber can then supplement the spring force holding the piston member in a closure position. Once the setting operation has been terminated the housing chamber is relieved of pressure so the response pressure is determined solely by the spring force. As will become apparent, the invention also provides hydraulic control apparatus for controlling a pressure-fluid operated roof support prop of mining apparatus; said apparatus comprising: main pressure fluid feed and return lines, a manually-operable control device for selectively connecting the feed and return lines to working chambers of the prop to effect extension and retraction thereof, a pressurerelief valve device having a piston member with relief borings slidably mounted in a guide piece provided with an Oring seal engaging on the piston member, a housing locating the guide piece and the piston member, a spring in the housing acting on the piston member to hold the latter in a position with the valve device closed, a fluid connection between the relief borings of the piston member and the particular working chamber of the prop which is charged with pressure fluid to effect extension and setting of the prop, the piston member being movable by excessive pressure above a response pressure set by the spring to 2 GB 2 096 223 A 2 open the valve device and a further fluid connection leading to the chamber in the housing to expose the chamber to pressure to supplement the spring closure force and make the response pressure significantly higher when the control device connects the working chamber of the prop to the pressure line.
The invention may be understood more readily, and various other aspects and features of the invention may become apparent, from consideration of the following description.
An embodiment of the invention will now be described, by way of example only, with reference to the accompanying drawing which is a schematic representation of a hydraulic control apparatus constructed in accordance with the invention.
As shown in the drawing, control apparatus has a setting valve device 11 connected by way of example through conduits or lines 13, 14 to the working chambers 10', 1 W of an hydraulic prop 10 and to pressure fluid feed and return lines P, R. A non-return valve 43 is incorporated in the line 13. It is also possible to connect the valve device 11 to several props instead of a single prop as shown. The valve device 11 is capable of adopting one of three settings or states depicted schematically in the drawing. The valve device 11 preferably has a housing with flat surfaces for face-to-face mounting at some convenient location and employs a rotary slide valve actuated by a pivotable control lever accessible at the exterior of the housing. The valve device 11 is provided with an automatic return mechanism the so-called -dead-man's handle- - which automatically brings the control lever back to a neutral position when released. This neutral position corresponds to a neutral state or setting designated 0 and shown to be adopted in the drawing. In the state 0, the device 11 connects the chamber 1011 to the return line R while effectively isolating the chamber 10' from the pressure line P. With the valve device 11 set to the control state designated 1, the chamber 10' is connected to the pressure feed line P via the valve 110 43 while the chamber 1 W is connected to the return line R. This setting state 1 initiates extension and setting of the prop 10. With the valve device 11 set to the control state designated 2, the chamber 10' is connected to the 115 return line R while the chamber 1 W is connected to the pressure feed line P. This setting state 2 initiates positive retraction of the prop 1. With the device 11 set to the active states 1 or 2, the typical flow rate of pressure fluid through the device 11 is 50 litres per minute at a typical working pressure in the feed line P of about 400 bars. A pressure-relief valve device 12 has its inlet connected to the line 13 leading to the chamber 10' and hence to the chamber 10' of the prop 10. The device 12 has its outlet connected to 125 the inlet side of the valve 43 and hence to the fluid return R when the valve device 11 is set to the state 0 as shown.
The relief-valve device 12 is arranged to have automatic pressure control. The pressure-relief valve device 12 is composed of a guide 32 screwed into the open end of a cylindrical housing 33 and a piston or valve member 30 guided for sliding in main bore 31 of the guide 32. The housing 33, contains a spring 34 which bears on the inner end wall of the housing 33 and on a pressure plate 35 engaging on a domed head 36 of the valve member 30. The bore 31 of the guide 32 leads through a conduit or line 37 to the conduit or line 13 connected to the prop working chamber 10'. An 0-ring seal 38 is contained in a groove in the wall of the bore 31 and seals to the exterior periphery of a stem of the valve member 30. This stem contains an axial bore and radial borings open to the periphery and can be raised to bring the radial borings above the seal 38 to permit fluid to pass into the housing 33. The axial bore in the valve member 30 forming the valve inlet leads through the auide 32 and a conduit 37 to the line 13 as shown. The interior 3 9 of the housing 33, forming the outlet of the device 12, is connected through a passage 40 in the guide 32 to an annular chamber 41 which in turn is connected through a conduit or line 42 to the line 13 so that the non- return valve 43 is disposed between the junctions of the line with the lines 37, 42. The device 12 can be set to respond normally at 370 bars. If the setting valve 11 is set to state 1, the chamber 101 is connected to the pressure line P and the prop 10 extends. The pressure prevailing in the line 13 leading to the chamber 10' is transmitted through the line 42, the chamber 41 and the passage 40 into the chamber 39 and hence acts with the spring 34 to hold the valve member 30 in a closed position. The pressure in the line 13 is also transmitted through the line 37 to the borings in the valve member 30 but the valve member 30 cannot become raised to open the valve because of the additive spring and pressure force acting in the opposite closing direction. Hence, when the prop 10 is being extended and set the device 12 cannot normally open. When the prop 10 has become set and the device 11 is set back to its neutral state 0 the chamber 39 becomes connected via the passage 40 and the line 42 and the device 11 to the return line R. Consequently, the chamber 39 is relieved and only the closure force of the spring 34 acts on the valve member 30. Consequently should the pressure in the chamber 10' rise beyond the response setting of the device 12 the valve member 30 will rise to allow pressure relief. The change over to permit the valve device 12 to function is achieved automatically whenever the device 11 adopts its neutral state 0.

Claims (4)

1. Hydraulic control apparatus for controlling the operation of mine roof support props; said apparatus comprising a control valve device for selective connecting first and second working chambers of an associated support prop to pressure fluid feed and return lines to effect extension and retraction of the props and a 4 3 GB 2 096 223 A 3 pressure-relief valve device which is connected to 30 main pressure fluid feed and return lines, a the first working chamber of the prop which is charged with pressure fluid by the control valve device when the prop is to be extended and set, said relief valve device being connectible to the return line to prevent excessive pressure in the first chamber and control means which automatically changes the response pressure of the relief valve device so that the response pressure of the relief valve device is higher when the associated prop is being extended and set than it is when the prop has become set.
2. Apparatus according to claim 1, wherein the pressure-relief valve device has a spring-loaded piston member slidably mounted in a guide piece the piston member having axial and radial bores acting as an inlet, the guide piece having an 0-ring seal mating with the piston member and a housing containing a chamber locating the guide piece and the piston member, said chamber acting as an outlet and wherein the control means serves to connect the chamber in the housing to the pressure line when the prop is being extended and set so that the closure force exerted on the piston member by the spring is supplemented by the pressure in the chamber.
3. Hydraulic control apparatus for controlling a pressure-fluid operated roof support prop of mining apparatus; said apparatus comprising:
manually-operable control device for selectively connecting the feed and return lines to working chambers of the prop to effect extension and retraction thereof, a pressure-relief valve device having a piston member with relief borings slidably mounted in a guide piece provided with an 0-ring seal engaging on the piston member, a housing locating the guide piece and the piston member, a spring in the housing acting on the piston member to hold the latter in a position with the valve device closed, a fluid connection between the relief borings of the piston member and the particular working chamber of the prop which is charged with pressure fluid to effect extension and setting of the prop, the piston member being movable by excessive pressure above a response pressure set by the spring to open the valve device and a further fluid connection leading to the chamber in the housing to expose the chamber to pressure to supplement the spring closure force and make the response pressure significantly higher when the control device connects the working chamber of the prop to the pressure line.
4. Apparatus substantially as described with reference to, and as illustrated in the accompanying drawing.
Printed for Her Majesty's Stationery Office by the Courier Press, Leamington Spa, 1982. Published by the Patent Office, 25 Southampton Buildings, London, WC2A lAY, from which copies may be obtained
GB8215240A 1979-04-12 1980-04-08 Improvements in hydraulic control apparatus for controlling the operation of mine roof support props Expired GB2096223B (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE2914884A DE2914884C2 (en) 1979-04-12 1979-04-12 Control device for a hydraulic ram removal with associated automatic repositioning

Publications (2)

Publication Number Publication Date
GB2096223A true GB2096223A (en) 1982-10-13
GB2096223B GB2096223B (en) 1983-05-11

Family

ID=6068183

Family Applications (2)

Application Number Title Priority Date Filing Date
GB8215240A Expired GB2096223B (en) 1979-04-12 1980-04-08 Improvements in hydraulic control apparatus for controlling the operation of mine roof support props
GB8011620A Expired GB2047316B (en) 1979-04-12 1980-04-08 Hydraulic control apparatus for controlling the operation of mine roof support props

Family Applications After (1)

Application Number Title Priority Date Filing Date
GB8011620A Expired GB2047316B (en) 1979-04-12 1980-04-08 Hydraulic control apparatus for controlling the operation of mine roof support props

Country Status (8)

Country Link
AU (1) AU533562B2 (en)
BE (1) BE882725A (en)
CA (1) CA1138303A (en)
DE (1) DE2914884C2 (en)
FR (1) FR2455673B2 (en)
GB (2) GB2096223B (en)
PL (1) PL125322B1 (en)
ZA (1) ZA802130B (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2168100A (en) * 1984-12-10 1986-06-11 Ct Kt Maszyn Gorniczych Komag Changing the machinability and workability of a coal bed, by varying the thrust applied to the roof
GB2184766A (en) * 1985-12-28 1987-07-01 Bergwerksverband Gmbh Finishing control for face supports
GB2243640A (en) * 1990-05-02 1991-11-06 Meco Mining Equip A mine roof support
CN103775115A (en) * 2014-01-21 2014-05-07 焦作欣扬程煤矿设备有限公司 Side-sway shifting vertical pressure cylinder machine

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3128279A1 (en) * 1981-07-17 1983-02-03 Gewerkschaft Eisenhütte Westfalia, 4670 Lünen ADJUSTMENT CONTROL FOR A HYDRAULIC STAMP EXTENSION AND HYDRAULICALLY CONTROLLED CHECK VALVE
DE3212747A1 (en) * 1982-04-06 1983-10-06 Gewerk Eisenhuette Westfalia DEVICE FOR STROKE CONTROL OF A CYLINDER GROUP OF A HYDRAULIC REMOVAL SYSTEM, IN PARTICULAR FOR SETTING THE STAMP OF A SCREAM REMOVAL UNIT
DE3301674C1 (en) * 1983-01-20 1984-01-05 Hermann Hemscheidt Maschinenfabrik Gmbh & Co, 5600 Wuppertal Control system for hydraulic stamps on walking frames
GB2137314B (en) * 1983-03-26 1986-07-23 Dobson Park Ind Valve for mine support
DE3931625C1 (en) * 1989-09-22 1990-08-09 Hermann Hemscheidt Maschinenfabrik Gmbh & Co, 5600 Wuppertal, De Underground mine roof support - maintains constant residual pressure during advance
GB2274325B (en) * 1993-01-13 1996-04-03 Meco Mining Equip A yield valve

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1024167A (en) * 1964-02-14 1966-03-30 Dowty Mining Equipment Ltd Roof support assembly suitable for use in mines
GB1135942A (en) * 1964-12-07 1968-12-11 Groetschel Karl Maria Improvements relating to roof supports for mine workings
GB1180578A (en) * 1967-03-06 1970-02-04 Podmoskovny G Pk I Exi Gornogo Advancing Mine Roof Supports
DE1290109B (en) * 1967-10-21 1969-03-06 Gewerk Eisenhuette Westfalia Stamp for expansion or bracing in the face / route transition
DE1750834A1 (en) * 1968-06-10 1971-04-29 Gewerk Eisenhuette Westfalia Pressure relief valve cartridge with piston O-ring seal
DE2146502C3 (en) * 1971-09-17 1982-04-29 Gewerkschaft Eisenhütte Westfalia, 4670 Lünen Valve arrangement for setting hydraulic pit rams with high setting force
DE2749312C2 (en) * 1977-11-04 1984-12-20 Gewerkschaft Eisenhütte Westfalia, 4670 Lünen Control device with automatic repositioning for hydraulic ram removal
DE2803283C2 (en) * 1978-01-26 1992-12-10 Gewerkschaft Eisenhütte Westfalia, 4670 Lünen Pressure relief valve for hydraulic pit rams

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2168100A (en) * 1984-12-10 1986-06-11 Ct Kt Maszyn Gorniczych Komag Changing the machinability and workability of a coal bed, by varying the thrust applied to the roof
GB2184766A (en) * 1985-12-28 1987-07-01 Bergwerksverband Gmbh Finishing control for face supports
GB2184766B (en) * 1985-12-28 1989-03-30 Bergwerksverband Gmbh Finishing control for face supports
GB2243640A (en) * 1990-05-02 1991-11-06 Meco Mining Equip A mine roof support
US5073067A (en) * 1990-05-02 1991-12-17 Meco Mining Equipment Limited Mine roof support
AU639990B2 (en) * 1990-05-02 1993-08-12 Meco Mining Equipment Limited A mine roof support
GB2243640B (en) * 1990-05-02 1994-01-12 Meco Mining Equip A mine roof support
CN103775115A (en) * 2014-01-21 2014-05-07 焦作欣扬程煤矿设备有限公司 Side-sway shifting vertical pressure cylinder machine

Also Published As

Publication number Publication date
AU5710080A (en) 1980-10-16
DE2914884C2 (en) 1987-05-14
AU533562B2 (en) 1983-12-01
PL125322B1 (en) 1983-04-30
ZA802130B (en) 1981-05-27
BE882725A (en) 1980-07-31
FR2455673A2 (en) 1980-11-28
GB2096223B (en) 1983-05-11
GB2047316A (en) 1980-11-26
DE2914884A1 (en) 1980-10-30
FR2455673B2 (en) 1987-05-07
CA1138303A (en) 1982-12-28
PL223346A1 (en) 1981-01-30
GB2047316B (en) 1983-04-20

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PCNP Patent ceased through non-payment of renewal fee