US3592011A - Roof-supporting assembly for hydraulic roof-supporting system - Google Patents

Roof-supporting assembly for hydraulic roof-supporting system Download PDF

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Publication number
US3592011A
US3592011A US820808A US3592011DA US3592011A US 3592011 A US3592011 A US 3592011A US 820808 A US820808 A US 820808A US 3592011D A US3592011D A US 3592011DA US 3592011 A US3592011 A US 3592011A
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frames
roof
cylinders
cylinder
piston
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US820808A
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Friedrich-Alexander Brosowski
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KLOCKNER WERKE AG DUISBURG
KLOCKNER-WERKE AG DUISBURG
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KLOCKNER WERKE AG DUISBURG
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    • E—FIXED CONSTRUCTIONS
    • E21—EARTH 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
    • E21D23/04—Structural features of the supporting construction, e.g. linking members between adjacent frames or sets of props; Means for counteracting lateral sliding on inclined floor
    • E21D23/0409—Aligning or guiding means for the supports or for the constitutive parts of the supports
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH 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

Definitions

  • This invention relates to a roof-supporting assembly for a hydraulic roof-supporting system for longwall faces, which roof-supporting assembly comprises three frames placed side by side of which either the two outer frames jointly or the frame in the middle can be advanced and wherein the frames are coupled by paired control cylinders operable in contrary directions for correcting the relative positions of the frames, the annular piston face in one of each pair of cylinders having the same effective cross-sectional area as the full piston face in the other cylinder and the chamber on the full piston face side in one control cylinder being connected to the chamber on the annular piston face side in the other cylinder for keeping the frames parallel.
  • the invention permits the available length of advance of the frames to be increased without at the same time in any way impairing the functional reliability of the control cylinders.
  • each control cylinder comprises two parallel single cylinders which are located side by side and firmly interconnected, and which contain pistons to which pressure is simultaneously applied urging said pistons in contrary directions, the piston rod of each piston being linked to one of the neighboring frames and being guided so that it cannot rotate in its cylinder.
  • each individual cylinder need be attached to only one of the neighboring frames because the cylinders themselves cannot rotate.
  • FIG. I is a plan of a roof-supporting system according to the invention prior to the center frame being advanced
  • FIG. 2 is a view similar to FIG. 1 showing the system after the center frames has been advanced
  • FIG. 3 is a perspective fragmentary view of three props of frames forming an assembly, showing the division of the control cylinders into pairs, and
  • FIG. 4 is a part sectional side elevational view, on an enlarged scale, of a control cylinder of the system according to the invention.
  • each assembly comprises three parallel frames A, B and C.
  • each frame consists of a roofbar 1, two hydraulic props 2 which align in the direction of the roofbar and a soleplate3.
  • the three frames are of completely identical construction.
  • Double-acting ram cylinders 6 and 7 for advancing the frames are interposed between each two neighboring frames. By appropriately admitting hydraulic fluid into these ram cylinders the center frame B can be advanced while the two outer frames A and C remain tight. If hydraulic fluid is admitted into the ram cylinders 6 and 7 in the oppositely acting direction the two outer frames A and C can be advanced while the center frame B remains tight.
  • the props 2 of the outer frame A are linked to the corresponding props 2 of the center frame B by control cylinders 11 and 12.
  • the props 2 of the outer frame C are linked to the corresponding props 2 of the center frame B by control cylinders l4 and 15.
  • the cylinders 11 and 14 as well as the cylinders 12 and 15 form pairs and they are operated in contrary directions for correcting the relative positions of the frames.
  • the cylinders of each pair differ slightly in size.
  • the annular piston face in the cylinder 11 has exactly the same effective cross-sectional area as the full piston face in the corresponding cylinder 14, and the same applies to the two other control cylinders 12 and 15, which are attached to the rear ends of the frames.
  • the working chambers on the full piston face sides in the cylinders 14 and 15 are connected to the chambers on the annular piston face sides in the two control cylinders 11 and 12.
  • the piston displacements in the paired control cylinders are always equal. If during a change in direction for instance the soleplate of the center frame B should be pulled out of alignment, the props 2 of the center frame B will be tilted. However, at the end of the advance of this frame the contradirectional admission of hydraulic fluid into the above-defined chambers in the paired control cylinders operates to correct the positions of the props and of the frame.
  • FIGS. 3 and 4 show a pair of control cylinders 11 and 14 in greater detail. From these figures it is seen that each of the control cylinders is actually formed by two single cylinders 40 and 41. Since all the control cylinders are of identical construction only the construction of the control cylinder 14 need be described in detail.
  • the two single cylinders 40 and 41 are placed parallel side by side. They may be firmly interconnected in any convenient way, the connection being shown as a weld 42 in the embodiment illustrated.
  • the pistons in the single cylinders 40 and 41 of which one is shown in FIG. 4 at 43 move in opposite directions. Hence, pressure is applied to the piston face 44 and at the same time pressure is also applied to the face of the piston that cannot be seen inside the single cylinder 40. In other words, the hydraulic pressure in the two cylinders acts in contrary directions.
  • the overall length of the control cylinder will be three times the maximum stroke of one of the pistons and this length will contract to the length of the piston stroke when the piston rods are fully retracted.
  • the ends of the piston rods 45 and 46 are provided with transverse bores 48 and 49 which are adapted to receive pivot pins 50 which in turn are received in fork-shaped members 51 formed on the shackles 13.
  • the bores 4% and 49 are provided in transverse head members 53 and S4.
  • the head member 54 on the piston rod 46 of the single cylinder 41 carries a lateral arm 53 to which a guide rod 56 extending parallel to the piston rod 46 and the cylinder 41 is attached.
  • This guide rod is adapted to slide in a sleeveshaped guide 57 secured to the body of the cylinder 41.
  • This arrangement prevents the piston rods 45 and 46 and their associated pistons from rotating inside their cylinders 40 and 41.
  • a roof-supporting assembly for a hydraulic roof-supporting system which roof-supporting assembly comprises three frames placed side by side of which either the two outer frames jointly or the frame in the middle can be advanced and wherein the frames are coupled by paired control cylinders operable in contrary directions for correcting the relative positions of the frames, the chamber on the full piston face side in one control cylinder being connected to the chamber on the annular piston face side in the other cylinder for keeping the frames parallel, characterized in that each control cylinder comprises two parallel single cylinders which are located side by side means rigidly connecting said cylinders, and pistons in said cylinders to which pressure is simultaneously applied urging said pistons in contrary directions, means to link the piston rod of each piston to one of the neighboring frames, and means to guide each piston so that it cannot rotate in its cylinder.
  • a roof-supporting assembly comprising a head member on the outer end of each piston rod, each head member having a transverse bore, a pivot pin in each bore, shackles connected to the frames and fork-shaped members on said shackles to receive said pivot pins respectively.

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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)
  • Architecture (AREA)
  • Structural Engineering (AREA)
  • Pit Excavations, Shoring, Fill Or Stabilisation Of Slopes (AREA)
  • Conveying And Assembling Of Building Elements In Situ (AREA)
  • Actuator (AREA)

Abstract

This invention relates to a roof-supporting assembly for a hydraulic roof-supporting system for longwall faces, which roofsupporting assembly comprises three frames placed side by side of which either the two outer frames jointly or the frame in the middle can be advanced and wherein the frames are coupled by paired control cylinders operable in contrary directions for correcting the relative positions of the frames, the annular piston face in one of each pair of cylinders having the same effective cross-sectional area as the full piston face in the other cylinder and the chamber on the full piston face side in one control cylinder being connected to the chamber on the annular piston face side in the other cylinder for keeping the frames parallel.

Description

United States Patent [72] Inventor Friedrich-Alexander Brosowski Castrop-Rauxel, Germany [21] Appl. No. 820,808
[22} Filed May 1,1969
[45] Patented July 13, 1971 i 73] Assignee Klockner-Vi'erke AG. Duisburg, Germany [32] Priority July 1, 1968 [33] Germany [54] ROOF-SUPPORTING ASSEMBLY FOR HYDRAULIC ROOF-SUPPORTING SYSTEM 3 Claims, 4 Drawing Figs.
[52] U.S.Cl 61/45, 248/357 [51] lnt.Cl E2ld 15/44 [50] Field of Search 6 1 /45.2; 348/357; 299/31, 33
[56] References Cited UNlTED STATES PATENTS 3,505,823 4/1970 Bell 61/45 D 3,120,105 2/1964 Kibble etal 61/45 FOREIGN PATENTS 766,537 1/1957 Great Britain 1. 61/45 874,435 8/1961 Great Britain 61/45 1,028,516 4/1958 Germany 61/45 1,169,399 5/1964 Germany 61/45 Primary Examiner- Dennis L. Taylor Attorney-Malcolm W. Fraser ABSTRACT: This invention relates to a roof-supporting assembly for a hydraulic roof-supporting system for longwall faces, which roof-supporting assembly comprises three frames placed side by side of which either the two outer frames jointly or the frame in the middle can be advanced and wherein the frames are coupled by paired control cylinders operable in contrary directions for correcting the relative positions of the frames, the annular piston face in one of each pair of cylinders having the same effective cross-sectional area as the full piston face in the other cylinder and the chamber on the full piston face side in one control cylinder being connected to the chamber on the annular piston face side in the other cylinder for keeping the frames parallel.
PATEr-HFHJuumn 3,592,011
sum 2 m 2 INVENTOR ROOF-SUPPORTING ASSEMBLYFOR HYDRAULIC ROOF-SUPPORTING SYSTEM SUMMARY OF THE INVENTION I This arrangement permits the frames to be kept parallel even when they are advanced on a rise or dip face because the direction of the advancing frames is continuously corrected by virtue of the pistons in the control cylinders being displaced through like distances. Special control means. for ensuring parallel advance of the frames are not therefore needed. The realignment of the frames need not take place until the advancing movement has been completed. For this purpose the hydraulic fluid is admitted into the control cylinders by programmed control means.
This has the advantage of simplifying control and of improving the safety of roof control since during self-advance of the roof-supporting assemblies the miner can keep his eye on the roof which he was unable to do in the past because his attention was concentrated on controlling the control cylinders.
When the advancing steps are long and the frames are placed in close juxtaposition, the disposition and accommodation of the control cylinders in the assemblies presents some difficulty. In such circumstances the fully extended length of the piston rods of the control cylinders is often insufficient to provide the desired length of each advancing step.
By subdividing the control cylinders the invention permits the available length of advance of the frames to be increased without at the same time in any way impairing the functional reliability of the control cylinders.
According to the invention this is achieved in that each control cylinder comprises two parallel single cylinders which are located side by side and firmly interconnected, and which contain pistons to which pressure is simultaneously applied urging said pistons in contrary directions, the piston rod of each piston being linked to one of the neighboring frames and being guided so that it cannot rotate in its cylinder.
This permits the advancing step to be considerably lengthened beyond that which single cylinders would permit. On the other hand, each individual cylinder need be attached to only one of the neighboring frames because the cylinders themselves cannot rotate.
Where hitherto two hydraulic frames were connected by two advancing ram cylinders in which pressure was simultaneously applied to the two pistons in contrary directions so that the piston moved in opposite directions, piston rods had to be used which extended through the length of the cylinder. Otherwise difficulties could have arisen because of the ability of the pistons to rotate in the cylinders. In the arrangement according to the invention the necessity of providing throughtype piston rods is avoided.
In practice rotation of the pistons in the cylinders is prevented by providing one piston rod of the two single cylin ders forming a control cylinder with a parallel guide rod which is firmly attached to said piston rod and slidably movable in guide means on one of the single cylinders.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a plan of a roof-supporting system according to the invention prior to the center frame being advanced,
FIG. 2 is a view similar to FIG. 1 showing the system after the center frames has been advanced,
FIG. 3 is a perspective fragmentary view of three props of frames forming an assembly, showing the division of the control cylinders into pairs, and
FIG. 4 is a part sectional side elevational view, on an enlarged scale, of a control cylinder of the system according to the invention.
DESCRIPTION OF PREFERRED EMBODIMENT OF THE INVENTION I trolling the roof at a longwall working face by placing assemblies of the illustratedkind side by side along the length of the face. Each assembly comprises three parallel frames A, B and C. In the illustrated embodiment each frame consists of a roofbar 1, two hydraulic props 2 which align in the direction of the roofbar and a soleplate3. The three frames are of completely identical construction.
Double-acting ram cylinders 6 and 7 for advancing the frames are interposed between each two neighboring frames. By appropriately admitting hydraulic fluid into these ram cylinders the center frame B can be advanced while the two outer frames A and C remain tight. If hydraulic fluid is admitted into the ram cylinders 6 and 7 in the oppositely acting direction the two outer frames A and C can be advanced while the center frame B remains tight.
The props 2 of the outer frame A are linked to the corresponding props 2 of the center frame B by control cylinders 11 and 12. The props 2 of the outer frame C are linked to the corresponding props 2 of the center frame B by control cylinders l4 and 15.
The cylinders 11 and 14 as well as the cylinders 12 and 15 form pairs and they are operated in contrary directions for correcting the relative positions of the frames. The cylinders of each pair differ slightly in size.
In actual fact the annular piston face in the cylinder 11 has exactly the same effective cross-sectional area as the full piston face in the corresponding cylinder 14, and the same applies to the two other control cylinders 12 and 15, which are attached to the rear ends of the frames. For keeping the frames in relative parallelism the working chambers on the full piston face sides in the cylinders 14 and 15 are connected to the chambers on the annular piston face sides in the two control cylinders 11 and 12. Hence, the piston displacements in the paired control cylinders are always equal. If during a change in direction for instance the soleplate of the center frame B should be pulled out of alignment, the props 2 of the center frame B will be tilted. However, at the end of the advance of this frame the contradirectional admission of hydraulic fluid into the above-defined chambers in the paired control cylinders operates to correct the positions of the props and of the frame.
FIGS. 3 and 4 show a pair of control cylinders 11 and 14 in greater detail. From these figures it is seen that each of the control cylinders is actually formed by two single cylinders 40 and 41. Since all the control cylinders are of identical construction only the construction of the control cylinder 14 need be described in detail.
The two single cylinders 40 and 41 are placed parallel side by side. They may be firmly interconnected in any convenient way, the connection being shown as a weld 42 in the embodiment illustrated. The pistons in the single cylinders 40 and 41 of which one is shown in FIG. 4 at 43 move in opposite directions. Hence, pressure is applied to the piston face 44 and at the same time pressure is also applied to the face of the piston that cannot be seen inside the single cylinder 40. In other words, the hydraulic pressure in the two cylinders acts in contrary directions. Consequently, when the piston rods 45 and 46 of the two single cylinders 40 and 41 forming the control cylinder 14 are fully extended, the overall length of the control cylinder will be three times the maximum stroke of one of the pistons and this length will contract to the length of the piston stroke when the piston rods are fully retracted.
The ends of the piston rods 45 and 46 are provided with transverse bores 48 and 49 which are adapted to receive pivot pins 50 which in turn are received in fork-shaped members 51 formed on the shackles 13.
The bores 4% and 49 are provided in transverse head members 53 and S4. The head member 54 on the piston rod 46 of the single cylinder 41 carries a lateral arm 53 to which a guide rod 56 extending parallel to the piston rod 46 and the cylinder 41 is attached. This guide rod is adapted to slide in a sleeveshaped guide 57 secured to the body of the cylinder 41.
This arrangement prevents the piston rods 45 and 46 and their associated pistons from rotating inside their cylinders 40 and 41.
What I claim is:
1. A roof-supporting assembly for a hydraulic roof-supporting system, which roof-supporting assembly comprises three frames placed side by side of which either the two outer frames jointly or the frame in the middle can be advanced and wherein the frames are coupled by paired control cylinders operable in contrary directions for correcting the relative positions of the frames, the chamber on the full piston face side in one control cylinder being connected to the chamber on the annular piston face side in the other cylinder for keeping the frames parallel, characterized in that each control cylinder comprises two parallel single cylinders which are located side by side means rigidly connecting said cylinders, and pistons in said cylinders to which pressure is simultaneously applied urging said pistons in contrary directions, means to link the piston rod of each piston to one of the neighboring frames, and means to guide each piston so that it cannot rotate in its cylinder.
2. A roof-supporting assembly according to claim 1, in which the ends of the piston rods are provided with pivot pins receivable in recesses in shackles connected to the frame.
3. A roof-supporting assembly according to claim 1, comprising a head member on the outer end of each piston rod, each head member having a transverse bore, a pivot pin in each bore, shackles connected to the frames and fork-shaped members on said shackles to receive said pivot pins respectively.

Claims (3)

1. A roof-supporting assembly for a hydraulic roof-supporting system, which roof-supporting assembly comprises three frames placed side by side of which either the two outer frames jointly or the frame in the middle can be advanced and wherein the frames are coupled by paired control cylinders operable in contrary directions for correcting the relative positions of the frames, the chamber on the full piston face side in one control cylinder being connected to the chamber on the annular piston face side in the other cylinder for keeping the frames parallel, characterized in that each control cylinder comprises two parallel single cylinders which are located side by side means rigidly connecting said cylinders, and pistons in said cylinders to which pressure is simultaneously applied urging said pistons in contrary directions, means to link the piston rod of each piston to one of the neighboring frames, and means to guide each piston so that it cannot rotate in its cylinder.
2. A roof-supporting assembly according to claim 1, in which the ends of the piston rods are provided with pivot pins receivable in recesses in shackles connected to the frame.
3. A roof-supporting assembly according to claim 1, comprising a head member on the outer end of each piston rod, each head member having a transverse bore, a pivot pin in each bore, shackles connected to the frames and fork-shaped members on said shackles to receive said pivot pins respectively.
US820808A 1968-06-01 1969-05-01 Roof-supporting assembly for hydraulic roof-supporting system Expired - Lifetime US3592011A (en)

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DE19681758448 DE1758448A1 (en) 1968-06-01 1968-06-01 Hydraulic longwall construction

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BE (1) BE732099A (en)
DE (1) DE1758448A1 (en)
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GB (1) GB1261118A (en)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2744992A1 (en) * 1977-10-06 1979-04-19 Gewerk Eisenhuette Westfalia WORK FOR A SHIELD OR FRAMEWORK, ETC.
FR2591658A1 (en) * 1985-12-14 1987-06-19 Gewerk Eisenhuette Westfalia Hydraulic aligner for striding roof support
US5584611A (en) * 1994-11-22 1996-12-17 Long-Airdox Roof support for underground excavations
CN102678140A (en) * 2012-05-30 2012-09-19 山西东华机械有限公司 Rotation device of hydraulic support retraction machine
US10774642B1 (en) * 2019-05-05 2020-09-15 Liaoning University Hydraulic support unit and hydraulic support for anti-rock burst roadway
CN112963181A (en) * 2021-02-24 2021-06-15 中国矿业大学 Forepoling top beam supporting device and using method thereof

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2808844C2 (en) * 1978-03-01 1983-04-14 Gosudarstvennyj proektno-konstruktorskij i technologičeskij institut pod"emno-transportnogo mašinostroenija, Novomoskovsk, Tul'skaja oblast' Auxiliary support to secure the longwall / route transition when the seam is moderately inclined
GB8328281D0 (en) * 1983-10-22 1983-11-23 Dobson Park Ind Mine roof supports
DE3410973C2 (en) * 1984-03-24 1986-06-05 Festo KG, 7300 Esslingen Pressure medium-operated slide-like feed device

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB766537A (en) * 1953-02-25 1957-01-23 Coal Industry Patents Ltd Improvements in mine roof supports
DE1028516B (en) * 1955-07-22 1958-04-24 Arnold Haarmann Dr Ing Wandering pit construction for mining operations
GB874435A (en) * 1956-12-12 1961-08-10 Arnold Haarmann Advancing mine roof support structure for mine working faces
US3120105A (en) * 1959-09-25 1964-02-04 Coal Industry Patents Ltd Self-advancing mine roof supports
DE1169399B (en) * 1956-06-18 1964-05-06 Gewerk Eisenhuette Westfalia Removable expansion for mining operations
US3505823A (en) * 1967-07-19 1970-04-14 Gunter Bell Hydraulic support systems for mine workings

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB766537A (en) * 1953-02-25 1957-01-23 Coal Industry Patents Ltd Improvements in mine roof supports
DE1028516B (en) * 1955-07-22 1958-04-24 Arnold Haarmann Dr Ing Wandering pit construction for mining operations
DE1169399B (en) * 1956-06-18 1964-05-06 Gewerk Eisenhuette Westfalia Removable expansion for mining operations
GB874435A (en) * 1956-12-12 1961-08-10 Arnold Haarmann Advancing mine roof support structure for mine working faces
US3120105A (en) * 1959-09-25 1964-02-04 Coal Industry Patents Ltd Self-advancing mine roof supports
US3505823A (en) * 1967-07-19 1970-04-14 Gunter Bell Hydraulic support systems for mine workings

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2744992A1 (en) * 1977-10-06 1979-04-19 Gewerk Eisenhuette Westfalia WORK FOR A SHIELD OR FRAMEWORK, ETC.
FR2591658A1 (en) * 1985-12-14 1987-06-19 Gewerk Eisenhuette Westfalia Hydraulic aligner for striding roof support
US5584611A (en) * 1994-11-22 1996-12-17 Long-Airdox Roof support for underground excavations
CN102678140A (en) * 2012-05-30 2012-09-19 山西东华机械有限公司 Rotation device of hydraulic support retraction machine
CN102678140B (en) * 2012-05-30 2014-06-18 山西东华机械有限公司 Rotation device of hydraulic support retraction machine
US10774642B1 (en) * 2019-05-05 2020-09-15 Liaoning University Hydraulic support unit and hydraulic support for anti-rock burst roadway
CN112963181A (en) * 2021-02-24 2021-06-15 中国矿业大学 Forepoling top beam supporting device and using method thereof

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BE732099A (en) 1969-10-27
DE1758448A1 (en) 1971-01-28
GB1261118A (en) 1972-01-19
FR2010003A1 (en) 1970-02-13

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