US3525227A - Mine roof supports - Google Patents

Mine roof supports Download PDF

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Publication number
US3525227A
US3525227A US746070A US3525227DA US3525227A US 3525227 A US3525227 A US 3525227A US 746070 A US746070 A US 746070A US 3525227D A US3525227D A US 3525227DA US 3525227 A US3525227 A US 3525227A
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United States
Prior art keywords
support
rams
roof
conveyor
elements
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Expired - Lifetime
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US746070A
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English (en)
Inventor
Kenneth George Hancock
Peter Frank Eastwood
Brian Worrall
Ronald Roy Reeves
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Gullick Ltd
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Gullick Ltd
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Priority claimed from GB3850967A external-priority patent/GB1222204A/en
Application filed by Gullick Ltd filed Critical Gullick Ltd
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    • 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
    • E21D23/04—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

Definitions

  • Mine roof supports of the advancing type comprise one or more roof contacting members, one or more floor contacting members with one or more props arranged therebetween and having two laterally spaced apart support advancing rams pivotally connected to the support and adapted for connection to an anchorage, for example a coalface conveyor.
  • Guide surfaces are provided on the support to co-operate with complementary first surfaces carried by adjacent supports, or co-operating first surfaces carried by independently movable parts of the same support, whereby during advancing movement of the support it is guided relative to an adjacent roof supporting member or members.
  • This invention relates to advancing mine roof supports of the type comprising one or more roof contacting members, one or more floor contacting members with one or more props arranged therebetween and having two laterally spaced apart support advancing rams pivotally connected to the support and adapted for connection to an anchorage, for example a coalface conveyer. More particularly the invention concerns the guidance of such a support during its advancing movement.
  • the advancing rams referred to may be single acting and used to advance the support to the conveyer or they may be double acting. In the latter case they may be used to advance the conveyor when the support is set to the roof and subsequently (the conveyer being retained in its advanced position by adjacent supports), used to advance the support, after its release from supporting the roof, up to the conveyor. Longitudinal movement of the conveyer frequently occurs during its advancement and provision for this must be made in the manner in which the advancing rams are connected between the conveyer and the support; otherwise the rams will be damaged, for example by bending of their piston rods. Provision should also be made to ensure that when the support is advanced it takes up a position normal to the conveyer.
  • a mine roof support of the type described comprises first guide surfaces carried by the support and adapted to co-operate with complementary first surfaces carried by adjacent supports, or co-operating first surfaces carried by independently movable parts of the same support, whereby the support, or that part thereof to which the aforementioned rams are connected, is guided relative to an adjacent roof supporting member or members over a substantial part of the support advancing stroke of the rams and the restraint imposed by the co-operating guide surfaces is removed over the final advancing movement of the support so as then to permit lateral movement thereof.
  • first guide surfaces carried by the support comprise forward and rear sections providing discontinuous guide surfaces.
  • connection of the rams to the anchorage comprises link members pivotally connected to the rams and adapted for pivotal connection to the anchorage, each link member having a second guide surface arranged to co-operate with a second surface on the support so as to guide the support into a predetermined position relative to the anchorage during closure of the rams, the link members being so formed and the pivotal connections between the anchorage, the link members and the rams being so arranged that, when the support approaches its fully advanced position, the axis of each ram is inclined to a line joining the pivotal connections at the anchorage and the support, whereby a leverage is exerted on the link members tending to exert a lateral force on the support so as to steer it into a predetermined positlon relative to the anchorage or restrain it from moving away from that position.
  • each link member is formed with a projection cam or the like beyond which the leading edge of the co-operating second surface on the support passes, when the support is fully advanced to the anchorage, so that the support is guided or steered into its predetermined position even though it may not be fully advanced to the anchorage.
  • connections of the link members to the anchorage are arranged to permit relative vertical movement.
  • the link members may be provided with abutment surfaces for engagement with the anchorage so that, when double acting rams are provided, the anchorage may be advanced thereby.
  • Means may be provided to prevent overlapping of link members of adjacent supports, for example, during lateral movement of the anchorage relative to the supports.
  • FIGS. 1(1) (A), 1(I)(B), 1(II) (C) and 1(II) (D) show diagrammatically in plan successive positions of the parts in the advance of a mine roof support;
  • FIG. 2 is a diagrammatic scrap view in plan illustrating one method of connecting an advancing ram to an anchorage, e.g. a coalface conveyor;
  • FIG. 3 is a diagrammatic plan view showing in part only one ram, a preferred link member, the co-operating second surface of a support and an anchorage;
  • FIG. 4 is an elevation showing the connections between the ram, link member and anchorage of FIG. 3;
  • FIGS. 5(I) (A), 5(I) (B), 5(II) (C), and 5(II) (D) show diagrammatically in plan successive positions of the parts in the advance of a mine roof support;
  • FIGS. 1(I) (A)-1(II)-(D) are referred to collectively in some instances in the following descriptions as FIG. 1; and, FIGS. 5(1) (A)-5(II) (D) are referred to collectively in some instances as FIG. .5; and,
  • FIG. 6 is a fragmentary perspective view of two outer support elements and an inner or third support element, showing cooperating guide surfaces on the support elements.
  • a composite mine roof support which consists of two outer support elements 2, 3 in conjunction with an inner or third roof support element 4.
  • the elements 2, 3 are similar and each has a base 5A, 5B, two hydraulically operated telescopic props 6A, 7A, 6B, 7B, resiliently mounted thereon and a roof contacting member in the form of a roof bar 8A, 8B respectively carried by the props in known articulated manner, Brackets 9, 10 are secured to the rear ends of the bases 5A, 5B respectively.
  • the bases 5A, 5B are connected together by a substantial metal plate 11 having side lugs 12 which span the brackets 9, 10 and are connected to them by transversely disposed pins 13, the latter being located by split pins (not shown).
  • First and second double acting advancing rams 35, 36 have their piston rods pivotally connected to brackets 17 on the bases 5A, 5B and their cylinders are pivotally connected to links 38 (FIG. 1), 95 (FIG. 5) which are in turn pivotally connected to a conveyor 30, all the pivot axes being in the vertical plane.
  • the third roof of support element 4 comprises a base '41, two hydraulically operated props 43., 44 resiliently mounted thereon and a roof bar 42 carried by the props in known articulated manner.
  • the base 41 has sideways clearance (see position D) between the bases 5A, 5B the amount of clearance provided on either side being not less than the maximum anticipated longitudinal movement of the conveyor 30 during one cycle of advance.
  • the cylinder of a third advancing ram 45 has a horizontal pivot connection to the base 41 and its piston rod has a vertical pivot connection at 67 to a lever 68 intermediate the ends thereof.
  • the ends of the lever 68 have vertical pivot connections at 69, 70 to the rear ends of two members 71, 72 whose forward ends, cranked at a small angle, are horizontally pivotally connected at 73, 74 to the inwardly facing sides of the bases 5A, 5B of the elements 2 and 3 respectively.
  • the roof bar 42 comprises a rigid main portion 58 to which is bolted a narrower front portion 59 in the form of a leaf spring.
  • Plates 53A, 54A bolted to the bases 5A, 5B have tapered edges 55, 56 which comprise first guide surfaces which co-operate with complementary first surfaces on the third roof support element 4 whereby the outer elements 2, 3 of the support are guided over a substantial part of the support advancing stroke of the rams 35, 36.
  • the complementary first surfaces are constituted by an upwardly inclined plate 140 at the front end of the base 41 and a generally vertical plate 141 on each side which is joined to the upwardly inclined plate 140.
  • each link 38 comprises similar upper and lower link portions (the lower being masked in the drawing by the upper) having a common vertical pivot connection 90 to the conveyor 30 and they are arranged above and below a thrust member 91 which comprises an extension on the ram cylinder towards the conveyor 30.
  • the thrust member 91 is slotted at 92 and a pin 93 passes through the link portions and the slot 92.
  • the length of the slot 92 is such that on extension of the ram the free end 94 of the thrust member 91 engages a thrust plate or the like (not shown) on the conveyor 30 leaving clearance between the end of the slot 92 remote from the conveyor 30 and the pin 93.
  • FIG. 5 similar, but shorter, forward plates 53A, 54A are provided on the bases 5A, 5B of the support of FIG. 5.
  • the plates 53A are respectively formed with guide surfaces 53B, 55 and 54B, 56.
  • Rear plates 105, 106 are also provided, bolted to the bases 5A, 5B towards their rear ends, at such a height that they are clear of the upper surface of the base 41, each being provided with guide surfaces (forming a part of the first guides) 107, 108, 109, 110 similar to the surfaces 53B, 55 and 54B, 56 provided on the plates 53A, 54A.
  • Two bearing pads 111, 112 are mounted on a cross member 113 above the rear end of the base 41 in the way of the plates 105, 106 (positions A and B) which co-operate with the surfaces 107, 108, 109, 110.
  • the cylinder of the ram 36 is pivotally connected at 95A to one end of a link 95 whose other end is pivotally connected at 95B to a bracket 96 which is secured as by bolts and nuts to a coalface conveyor 30.
  • the link 95 has at its forward end two surfaces 97, 98 inclined at an angle to one another, which define limits of angular movement of the link 95 relative to the conveyer 30 by abutment with the bracket 96.
  • the surface 97 is abutting the bracket 96 and thereby limiting angular movement of the ram 36 away from the "base 5B. In this position the line of action of the ram 36 is shown at 99 and its lever arm about the pivot 95B is shown at 100.
  • the link 95 is provided with a second guide surface 101 culminating in a projection or cam 102 which guide surface and cam are adapted to co-operate with a second surface on the support which may conveniently be a vertical surface extending rearwardly from a forward location 103 on the base 5B.
  • the link may also include vertical surfaces 104 at its side remote from the support, seen more clearly in FIG. 4, for a purpose to be described. Also depicted in FIG. 3, in chain dotted lines, is the position of the ram 36, link 95 and base 5B when the support has been fully advanced to the conveyor 30 and guided--in a manner to be describedinto a predetermined position relative to the conveyor 30.
  • a leverage is thus exerted on the link 95 which, if its surface 98 has not yet abutted the bracket 96, imparts a lateral force on the support to steer it towards its final predetermined position as the ram 36 approaches its fully closed position.
  • the leverage exerted on the link 95 now acts to restrain movement of the support from its predetermined position.
  • FIG. 4 which includes an elevation of the bracket 96 it will be seen that in the way of the pivot 95B the bracket is formed as a yoke the upper and lower arms of which are spaced apart to permit relative vertical movement between the link 95 and the conveyor 30.
  • the elements 2, 3 of the composite support are released from supporting the roof and the rams 35, 36 are closed so as to advance the elements 2, 3 to a position adjacent to the conveyor again. Due to the tension force in the rams 35, 36 and the links 38, 95 the support elements 2, 3 will tend to be advanced into a position normal to the conveyor 30. It will be noted (FIG. 5B) that before advancement of the elements 2, 3 the links 95 are well forward and clear of the second surfaces on the bases 5A, 5B so the tension force in the rams will rotate the links 95 so that their surfaces 98 abut the brackets 96, as shown in FIG. 5B.
  • FIGS. 1C and 5C show them partially advanced. Their path of advancement will be defined by the orientation of the third roof support element 4, which is maintained in roof supporting position, due to the first surfaces on the base 41 co-operating with the first guide surfaces. That is to say, the first surfaces on the base 41 co-operate with the plates 53A, 54A (FIGS. 1 and 5) and the pads 111, 112 co-operate with the plates 105, 106 (FIG. 5).
  • the elements 2, 3 are prevented from twisting round due to closure of the ram 36 by interaction of the guide surfaces which have been described provided between the bases 5A, 5B and the element 4.
  • the amount to which elements 2, 3 can be twisted is limited by the clearance between the co-operating guide surfaces and the degree of twist permitted is arranged to be less than that which is required to cause either of the rams 35, 36 to foul their respective support elements 2, 3 for example, when the maximum movement of the conveyor transverse to the support has taken place.
  • the first guide surfaces 53B, 54B and 108, 110 move clear of the co-operating first surfaces on the element 4 so as to permit lateral movement of the elements 2, 3 and permit any necessary re-alignment of the elements 2, 3 with the conveyor 30.
  • Guide plates may be provided if desired on the conveyor 30 to engage bases 5A, SE to guide the elements 2, 3 into contact alignment with the conveyor 30 during the final stages of their advancing movement and after release of the restraint to lateral movement of the elements 2, 3.
  • this guidance may be provided by suitable shaping of the links 38, for example as shown at in FIGS. 3 to 5.
  • Movement of the conveyor 30 may occur, for example, in the direction of the arrow X, due to passage of a coal cutting machine when the elements 2, 3 are in the advanced position adjacent to the conveyor 30.
  • the rams 35, 36 may be vented and as the conveyor moves the link 95 pivots about the cam 102 which abuts the co-operating surface on the base 5B and in consequence the ram 36 is extended a small amount thus permitting the movement of the conveyor to take place without damage to the support.
  • the link 95 is so formed that during the final advancing movement of the support, the cam 102 is positioned so that it is enabled to engage the co-operating second surface at 103 a short distance, for example, 4 to 6 inches, before the support reaches its fully advanced position enabling the support to be guided or steered into its predetermined position relative to the conveyor even though the support may not be fully advanced.
  • a mine roof support comprising at least two roof support elements; means connecting said roof support elements for simultaneous advancing movement, each of said elements comprising a base, a roof bar and at least one extensible prop arranged therebetween; two advancing rams; means connecting said rams one to each of said elements, said rams being adapted for pivotal connection to an anchorage; first guide surfaces carried by said two elements; at least one adjacent support element; complementary guide surfaces on said one adjacent support element, said first guide surfaces being arranged to cooperate with said complementary guide surfaces whereby on closure of said rams to advance said roof support, said first guide surfaces and said complementary guide surfaces guide said roof support relatively to said at least one adjacent support element over a substantial part of the support advancing stroke of said rams, engagement of said cooperating guide surfaces restraining said at least two support elements from lateral movement, and the restraint imposed by said cooperating guide surfaces being removed over the final advancing movement of the support so as then to permit lateral movement thereof.
  • a mine roof support comprising two roof support elements; means connecting said roof support elements for simultaneous advancing movement, each element comprising a base, a roof bar and at least one extensible prop arranged therebetween; two advancing rams; means connecting said rams one to each of said elements, said rams being adapted for pivotal connection to an anchorage; first guide surfaces carried by said two elements; an independently moveable roof support member arranged between and laterally spaced from said roof support elements; complementary guide surfaces on said independently moveable roof supporting member, said first guide surfaces being arranged to cooperate with said complementary guide surfaces whereby, on closure of said rams to advance said roof support, said first guide surfaces and complementary guide surfaces guide said roof support relatively to said independently moveable roof supporting member over a substantial part of the support advancing stroke of said rams, engagement of said cooperating guide surfaces restraining said two support elements from lateral movement, and the restraint imposed by said cooperating guide surfaces being removed over the final advancing movement of the support so as then to permit lateral movement thereof.
  • a mine roof support as claimed in claim 2 including second surfaces on the support; link members, one pivotally connected to each advancing ram and adapted for pivotal connection to the anchorage; and a second guide surface on each link member arranged to cooperate with said second surfaces on the support so as, on closure of the rams, to guide the support into a predetermined position relative to the anchorage, the link members being so formed and the pivotal connections being so arranged that, when the support approaches its fully advanced position, the axis of each ram is inclined to a line joining the pivotal connection at the anchorage and the support, whereby a leverage is exerted on the link members tending to exert a lateral force on the support so as to steer it into a predetermined position relative to the anchorage or restrain it from moving away from that position.
  • a mine roof support as claimed in claim 1, said one adjacent support element comprising a third roof supporting element, said complementary first surfaces being provided on said third roof supporting element, the third element comprising a base, a roof bar and two eX- tensible props arranged therebetween, the third element having lateral clearance from and being located between said first two elements; a third advancing ram pivotally connected between said third element and the first two elements; and means to permit relative vertical and lateral movement between the third element and the first and second elements.
  • first guide surfaces comprise forward and rear sections providing discontinuous guide surfaces, the first and second advancing rams being double acting; a link member pivotally connected to each of the first and second advancing rams and being adapted for pivotal connection to the achorage; abutment surfaces on the link members adapted to engage the anchorage whereby, on extension of said rams, force is transmitted to said anchorage to move it away from said support; cam portions on the link members adapted to engage the support and transmit a lateral force thereto during closure of the rams; and generally vertical plate portions on the link members adapted to prevent overlapping of the link members with the link members of adjacent supports.
  • a mine roof support comprising a pair of support elements; means connecting said pair of support elements for simultaneous advancing movement, each element comprising a base, a roof bar and at least one extensible prop arranged therebetween; two advancing rams; means connecting said rams, one to each of said elements of said pair, said rams being adapted for pivotal connection to an anchorage; first guide surfaces carried by the pair of elements; an adjacent support element on each side of said pair of support elements; complementary guide surfaces on said adjacent support elements, said first guide surfaces being arranged to cooperate with said complementary guide surfaces whereby, on closure of said rams to advance said roof support, said first guide surfaces and complementary guide surfaces guide said roof support relatively to adjacent roof supporting members over a substantial part of the support advancing stroke of the rams, engagement of said cooperating guide surfaces restraining said two support elements from lateral movement, and in which the restraint imposed by said cooperating guide surfaces is removed over the final advancing movement of the support so as then to permit lateral movement thereof; second surfaces on said support; link members, one

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  • Engineering & Computer Science (AREA)
  • Mining & Mineral Resources (AREA)
  • Architecture (AREA)
  • Structural Engineering (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Geology (AREA)
  • Lining And Supports For Tunnels (AREA)
  • Escalators And Moving Walkways (AREA)
  • Chain Conveyers (AREA)
US746070A 1967-07-19 1968-07-19 Mine roof supports Expired - Lifetime US3525227A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB3321867 1967-07-19
GB3850967A GB1222204A (en) 1967-07-19 1967-07-19 Advancing mine roof supports

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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3812681A (en) * 1971-07-16 1974-05-28 Gullick Dobson Ltd Mine roof supports
US3987634A (en) * 1975-02-18 1976-10-26 Hermann Hemscheidt Maschinenfabrik Roof-supporting arrangement
US3991580A (en) * 1974-11-15 1976-11-16 Gullick Dobson Limited Mine roof supports
US4195953A (en) * 1977-12-29 1980-04-01 Gewerkschaft Eisenhutte Westfalia Advance mechanism for a mine roof support assembly
FR2448625A1 (fr) * 1979-02-07 1980-09-05 Hemscheidt Maschf Hermann Appareil pousseur pour chevalets hydrauliques de soutenement a fleche
FR2473109A1 (fr) * 1977-12-29 1981-07-10 Gewerk Eisenhuette Westfalia Dispositif d'avance pour soutenement hydraulique marchant

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3034645A1 (de) * 1980-09-13 1982-04-29 Gewerkschaft Eisenhütte Westfalia, 4670 Lünen Schreitwerk fuer einen schreitausbau, insbesondere fuer einen schild- oder bockausbau

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2644311A (en) * 1951-08-16 1953-07-07 Malloy Paul V Self-propelled mine roof prop
GB1026965A (en) * 1963-06-11 1966-04-20 Dowty Mining Equipment Ltd Advanceable roof supports suitable for use in mines
GB1044907A (en) * 1963-08-08 1966-10-05 Electro Hydraulics Ltd Improvements in or relating to mine roof supports
US3333426A (en) * 1964-04-11 1967-08-01 Gullick Ltd Self-advancing hydraulically extensible mine roof supports
US3355898A (en) * 1964-11-17 1967-12-05 Dowty Mining Equipment Ltd Roof support assembly
US3425229A (en) * 1962-11-10 1969-02-04 Karl Maria Groetschel Mine roof support

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1051783A (de) * 1900-01-01
GB930838A (en) * 1960-08-31 1963-07-10 Gullick Ltd Improvements in or relating to roof supports for mines and the like
FR1325840A (fr) * 1962-03-23 1963-05-03 Charbonnages De France Dispositif permettant de commander les déplacements d'un objet mobile muni de ses propres moyens de locomotion en fonction de sa position par rapport à un autre objet mobile dont il doit suivre les déplacements, applicable plus particulièrement aux soutènements marchants dans les mines
GB965172A (en) * 1962-04-06 1964-07-29 Gullick Ltd Improvements in or relating to roof supports for mines and the like
GB1057157A (en) * 1964-08-19 1967-02-01 Mastabar Mining Equip Co Ltd Improvements in and relating to mine roof supports

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2644311A (en) * 1951-08-16 1953-07-07 Malloy Paul V Self-propelled mine roof prop
US3425229A (en) * 1962-11-10 1969-02-04 Karl Maria Groetschel Mine roof support
GB1026965A (en) * 1963-06-11 1966-04-20 Dowty Mining Equipment Ltd Advanceable roof supports suitable for use in mines
GB1044907A (en) * 1963-08-08 1966-10-05 Electro Hydraulics Ltd Improvements in or relating to mine roof supports
US3333426A (en) * 1964-04-11 1967-08-01 Gullick Ltd Self-advancing hydraulically extensible mine roof supports
US3355898A (en) * 1964-11-17 1967-12-05 Dowty Mining Equipment Ltd Roof support assembly

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3812681A (en) * 1971-07-16 1974-05-28 Gullick Dobson Ltd Mine roof supports
US3991580A (en) * 1974-11-15 1976-11-16 Gullick Dobson Limited Mine roof supports
US3987634A (en) * 1975-02-18 1976-10-26 Hermann Hemscheidt Maschinenfabrik Roof-supporting arrangement
US4195953A (en) * 1977-12-29 1980-04-01 Gewerkschaft Eisenhutte Westfalia Advance mechanism for a mine roof support assembly
FR2473109A1 (fr) * 1977-12-29 1981-07-10 Gewerk Eisenhuette Westfalia Dispositif d'avance pour soutenement hydraulique marchant
USRE31346E (en) * 1977-12-29 1983-08-16 Gewerschaft Eisenhutte Westfalia Advance mechanism for a mine roof support assembly
FR2448625A1 (fr) * 1979-02-07 1980-09-05 Hemscheidt Maschf Hermann Appareil pousseur pour chevalets hydrauliques de soutenement a fleche

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JPS4834641B1 (de) 1973-10-23
DE1758675B1 (de) 1972-05-31

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