US3474627A

US3474627A - Roof supports for mine workings

Info

Publication number: US3474627A
Application number: US765564A
Authority: US
Inventors: Karl M Groetschel
Original assignee: Individual
Current assignee: Individual
Priority date: 1967-10-10
Filing date: 1968-10-07
Publication date: 1969-10-28
Anticipated expiration: 1986-10-28
Also published as: DE6801450U; DE1802010B1; GB1219897A

Description

9a. 28 1959 K. M. GROETSCHEL 3,474,627

ROOF SUPPORTS FOR MINE WQRKINGS 4 Sheets$heet 1 Filed 001:. 7, 1968 mvinrolp KARL main 030mm 99% BY W i ATTQQVEE Oct. 28, 1969 K. M. GROETSCHEL ROOF SUPPORTS FOR MINE WORKINGS 4 Sheets-Sheet 2 Filed Oct. 7. 1968 O on mm QN INVENT R Ka'rL Maria o'etschcL 5 BY M f ATTURl/EYS d 2 1969 K. M. GROETSCHEL. 3,474,527

RQQF SUPPORTS FOR MINE WORKINGS 4 Sheets-Sheet 3 Filed Oct. '7. 1968 INVENTOR.

Karl. Maria G'mdschel mm MN Om -N J 21:44 u I n .HVNI (A I I f m w 1h -a awn c 1969 K. M. ,GROETSCHEL 3, 5

ROOF SUPPORTS FOR MINE woaxmes Filed Oct. 1. 1968 4 Sheets-Sheet 4- 6/ 27 59 i 36- 3 l #76. Q. 47 i l i INVENTQR i Kavl. Maria. G OGtS IQL J BY z ){ye mnugl s United States Patent O 3,474,627 ROOF SUPPORTS FOR MINE WORKINGS Karl M. Groetschel, 44 Stolzestrasse, 463 Bochum, Germany Filed Oct. 7, 1968, Ser. No. 765,564 Claims priority, application Great Britain, Oct. 10, 1967, 46,258/ 67 Int. Cl. E21d 15/44, 23/08; F16m 13/00 US. C]. 61-45 14 Claims ABSTRACT OF THE DISCLOSURE A roof support for use primarily in underground mine workings wherein a flexible or articulated protective member is mounted to form a closure for an opening which would otherwise be afforded above a manway presented between a base and superstructure of the support when one part of the superstructure is advanced relatively to the second part during advancement of the support as a whole.

BACKGROUND OF THE INVENTION Field of the invention This invention relates to roof supports primarily for use in underground mine workings and is concerned with a roof support comprising a base, a plurality of poweroperated extensible props carried thereon, a roof-engaging superstructure, and traction means for advancing the support. Such supports are hereinafter referred to as being of the kind specified.

The invention has been developed primarily in relation to a roof support of the kind specified intended for use in coal mines where the method of mining adopted is that known generally as mechanised long wall coal mining. In this method coal-getting machinery is traversed along a coal face and the coal thus removed from the face is discharged or deflected onto a conveyor which extends along the coal face. The roof of the mine working extending over the top of the coal-getting machine and over the conveyor in a direction away from the coal face, and in a region on the side of the conveyor remote from the coalgetting machinery, requires to be supported at all times and it is important especially to provide early support to any newly exposed portions of the roof immediately adjacent to the coal face after the coal-getting machinery has moved past the roof support concerned along the coal face.

Forward advancement of a part of the superstructure to meet this requirement has, however, hitherto been accompanied by some diminution in the degree of protection provided over those areas of the roof situated adjacent to the rearward end of the roof support due to the creation of an opening presented by that part of the superstructure which temporarily remains stationary and which formerly was occupied by the rear end portion of the part of the superstructure which has undergone advancement.

Such opening need not necessarily be of very large dimensions but there is the possibility of loose roof material descending through this opening.

The object of the present invention is to provide an improved roof support whereby this disadvantage is overcome or reduced.

SUMMARY OF THE INVENTION With this object in view there is provided in a roof support for use in underground mine workings and comprising a base, a plurality of power-operated extensible props carried thereon, a roof-engaging superstructure, and traction means for advancing the support, the improvement wherein said base, props and roof-engaging super- Patented Oct. 28, 1969 structure define at least one manway extending laterally of said base between said base and said superstructure, said superstructure includes two parts, said parts of said superstructure are operably connected with said traction means for relative movement in a direction longitudinally of said base between a first position and a second position, in said first position said parts of said superstructure extend longitudinally of said base above said manway from one longitudinal boundary thereof to the opposite longitudinal boundary, in said second position said parts of said superstructure define an opening above said manway, a protective member is mounted in said opening, said protective member including a portion presenting a length which varies in conformity with the longitudinal dimension of said opening to span said opening longitudinally during relative movement of said parts of said superstructure from said first position to said second position and thereafter upon attainment of the latter.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described, by way of example, with reference to the accompanying drawings wherein:

FIGURE 1 is a view in side elevation and in crosssection on the line II of FIGURE 3 of one form of roof support of the kind specified incorporating a first embodiment of the present invention;

FIGURE 2 is a view similar to FIGURE 1 after advancement of one part of the superstructure;

FIGURE 3 is a plan view of the roof support of FIG- URES 1 and 2 with said part of the superstructure about its mid-position of advancement;

FIGURE 4 is a fragmentary view in side elevation of the roof support showing a second embodiment of the invention;

FIGURE 5 is a fragmentary view in side elevation showing a third embodiment of the invention; and

FIGURE 6 is a further fragmentary view in side elevation showing a fourth embodiment of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring firstly to the roof support and the embodiment of the invention incorporated therein, as seen in FIGURES 1 and 2, the roof support is of a form more fully described and illustrated in my co-pending application Ser. No. 682,867 which is to be considered part of the present disclosure. However, for convenience the following brief description of the main features of the roof support is now set forth below.

The support comprises inner and outer units, of which the latter includes a base element 10 and four hydraulic props indicated generally at 11, and a part of a superstructure (hereinbefore called the second part) carried by these props and indicated generally at 12.

The inner unit comprises a base element 13 on which are carried two hydraulic props 14, and a further part of the superstructure (herein called the first part) indicated generally at 15.

Traction means are operatively connected between the two units, such traction means comprising a doubleacting hydraulic ram 16 having a cylinder 17 accommodated conveniently in the base element 13 and connected thereto at the rearward end of the cylinder, and having a piston rod 18 projecting forwardly and connected at its forward end to the base element 10. In the embodiment illustrated the traction means is thus constituted wholly by the ram 17 mounted at the level of the base, but it would be possible to provide, in addition, a further part of the traction means in the form of a hydraulic ram operatively connected at the level of the superstructure to operate between the inner part 15 thereof and the outer parts 12, if desired.

It will be evident that between the inner and outer parts of the superstructure, as seen in FIGURE 3, there exist lateral clearance spaces 19, and similar lateral clearance spaces exist also between the inner and outer base element so that intrinsically the inner unit is capable of limited angular movement in a plane parallel to the floor of the mine working relatively to the outer unit.

The relative angular movement of the inner and outer units is controlled by guide means, as more fully described and claimed in my co-pending application Ser. No. 682,867, and which broadly comprise a transversely slidable plate operable from a hydraulic piston and cylinder unit 21 through the intermediary of a lever 22, the outer ends of the plate 20 engaging opposed laterally inwardly presented side faces afforded by side members 10a of the base element 10, one on each side of a longitudinally extending medial slot or opening in which the inner base element 13 moves, the plate, cylinder and lever being mounted on the latter. The side members are connected rigidly at their front and rear ends by

cross members

35a, 35b, of which the former as hereinafter mentioned also acts as a shield.

The guide means further comprises fixed guide elements 23 spaced longitudinally of the inner base element 13 from the transversely slidable plate 20, and also co-operating with the laterally inwardly presented sides of the outer base element to define a fulcrum about which relative angular movement between the two units can take place.

The second or outer part of the superstructure comprises laterally spaced beams 24 each formed conveniently of a pair of laterally spaced roof bars 25 of hollow rectangular section, usually termed, and herein called, box-section, united by vertically spaced horizontal plates 26 welded respectively to upper and lower flanges of the box-section roof bars. The two beams 24 are rigidly connected to each other by

cross members

27 and 28 adjacent to the rearward and. forward ends of the outer base element, such cross members being cranked downwardly in between the beams 12 to provide a channel or opening in which the inner or first part 15 of the superstructure is received.

The first or inner part of the superstructure is likewise conveniently formed of a pair of laterally spaced roof bars of box-section 29 connected by vertically spaced horizontal plates 30 welded to the upper and lower flanges of these roof bars and is of the same, or about the same, length as that of the beams 12.

It will be noted that the inner base element 13 is of about half the length of the outer base element 10 and, when advanced along the medial slot or opening afforded by the latter, as seen in FIGURE 2, an opening of considerable area would be created in the superstructure between the rearward end of the second part, as defined by the cross member 27 and rearward end portions of the beams 12, and the rearward end of the first or inner part 15. When in use in the method of long wall coal mining, the support is installed, as shown in FIGURE 1, at the side of a conveyor 32 remote from a coal face alongside which the conveyor 32 exists. The superstructure engages and supports portions of the roof of the mine working over the conveyor 32.

The coal winning machine ordinarily travels along a trackway aflorded by the conveyor 32 and when this has moved passed a particular one of the supports in a row thereof extending along the coal face, it is important to provide support to the roof newly exposed by the coal cut away by the machine. For this purpose the inner unit of the support is ordinarily advanced preparatory to any movement of the conveyor 32 in a direction towards the coal face by a traction ram provided for this purpose (not shown) on a selected number of the supports, and the piston rod whereof 31 is shown connected to a flange or rail 32a on the conveyor.

During the advancement of the inner part mining personnel may be stationed in the rearward one 33 of two manways 33 and 34 afforded in a direction laterally of the row supports between the base element and superstructure thereof and it is, therefore, important, for the safety of such personnel, to prevent the ascent of any loose material through the opening created as previously mentioned.

The risk of such material entering the manway 33 and the risk of further material entering the manway, as a result of caving or descent of the roof on the goaf or waste side of the support rearwardly thereof, is to some extent reduced by the provision of a shield member 35 which also functions as a member of the outer base element. Moreover, a dependent flexible shield member 36 supported from the cross member 27 further reduces the risk.

The present invention, however, provides a protective member which still further reduces the possibility of entry of material into the manway 33 by descent of the roof, as distinct from entry of material by sliding or displacement from the waste area.

This protective member is indicated generally at 38.

The protective member preferably of a width sufficient substantially to close the opening which would otherwise exist between the beams 24, cross member 27, and the rearward end of the first or inner part 15 of the superstructure, when the latter is advanced as shown in FIG- URE 2, and owing to its articulated, or possibly flexible, character, as hereinafter referred to, will accommodate any desired angular displacement between the inner and outer units as a result of operation of the guide means previously mentioned.

The form of protective member illustrated in FIG- URES 1 to 3 comprises a plurality of slat elements in the form of plates 39 which may be of steel or other suitable metal and which are articulately connected to each other at adjacent transverse edges by any suitable pivotally connecting means. For example, as shown, each plate may include sleeve-like bearing portions 40 welded to its rearward margin and spaced apart laterally to receive between them further sleeve-like bearing portions 41 welded to the forward margin of the plate 39 occupying the next rearward position.

At the forward extremity of the protective member the latter is pivotally connected to the rear end of the first or inner part 15 of the superstructure. This may be elfected by the provision of bearing sleeves 42 having attachment plates 43 extending into the interior of the roof bars 29 of this part of the superstructure and secured thereto in any suitable manner as, for example, by a bolt or other fastening element 44 securing the attachment plate 43 to webs 46 welded to, and spanning, the roof bars internally.

At each articulated connection the bearing portions are connected to each other by pivot pins 47.

The assembly of slat elements in eflfect forms a mat of which an operative portion extends between the rearward end of the first or inner part 15 of the superstructure and the cross member 27 upon which the rearward end of this operative portion rests. The protective member also includes a reserve portion which, as seen in FIGURE 1, depends from the rearward end of the operative portion at the rearward side of the cross member 27. The latter may be equipped with a pair of laterally spacer members 48 presenting rearward edge faces of curved convex form to provide for smooth sliding passage of the slat elements thereover when they are transferred from the reserve portion, indicated generally at 49, to the operative portion, indicated generally at 50 (FIGURE 3) where the inner unit is in an intermediate stage of advancement.

The operative portion of the protective member is provided with means for rigidifying same with respect to loads imposed by descent of loose roof material.

For this purpose stop means is associated operatively with each articulated connection between adjacent plates 39, so that when the latter span the length of the opening between the cross member 27 and the rearward end of the first or inner part 15 of the superstructure, these plates 39 are maintained in coplanar, or approximately co-planar, relation with each other and positively resist bending stresses imposed by any downward loading. The plates are, however, free to pivot at their articulated connections in the opposite direction so that they can depend freely when forming the reserve portion 49 and are not damaged by descent of roof material in the goat or waste area as when caving of the roof takes place.

The preferred form of stop means comprises a plate element 51 rigidly secured, as by welding, to the rearward margin of each plate 39' at the upper side thereof, and spanning the articulated connection through the gap afforded between bearing portions 41 to overlie and abut the forward margin of the next plate 39 at the rear thereof.

The dependent reserve portion 49 of the protective member establishes tensile loading of the operative portion 50. Such tension could be augmented, if desired, by spring means such as one or more coiled tension springs connecting the lower end of the reserve portion 49 with the outer base element 10. Such spring means would be selected to have a strength to provide proper tension in the operative portion 50 without imposing any undesirable load to advancement of the inner unit.

In the embodiment illustrated in FIGURE 4-, the mat is formed of flexible sheet material, for example rubber, possibly reinforced by one or more layers of a woven fabric such as canvas.

In this embodiment the reserve portion of the mat is stored on a roller 54 journalled rotatably about a horizontal axis between brackets 55 welded or otherwise secured at adjacent opposite ends of the cross member 27.

The operative portion of the mat, as indicated at 50, is maintained in a state of tension by spring means tending to rotate the roller 54 in an anti-clockwise direction. Such spring means may comprise one or more coiled compression springs 57 connected between the base element and pulleys or drums fast with the roller around which chains, cables or similar elements connected to the upper ends of the springs 57 are lapped and to which possibly such elements are secured. Alternatively a torsion spring co-axial with the roller, and possibly disposed internally thereof, may be used.

The rearward end of the mat may also be secured to the roller by any suitable fastening means.

The height of the roller is preferably such that the operative portion of the mat inclines in a direction from front to rear so that loose material from the roof, as seen at 58, tends to be discharged rearwardly to the rearward side of a dependent static shield member ordinarily termed a flushing shield (not shown) and which may be secured at its upper end to the cross member 27.

In the alternative embodiment illustrated in FIGURE 5, a mat similar to that described with reference to FIG- URE 2 has its reserve portion stored on a similar roller 54 but instead of extending directly between the roller and the rearward end of the long beam, such mat embraces the cross member 27, the rearwardly presented profile of which is in accordance with that already described with reference to FIGURE 1.

In the alternative embodiment shown in FIGURE 6, the mat again is formed from flexible sheet material such, for example, as that already mentioned. Instead of its reserve portion being stored on a roller such reserve portion depends as a folded body or loop 59. Conveniently such loop 59 is disposed between the dependent shield 36 previously mentioned and the shield 47 of the rearward end of the base element 10. The rearward end of the mat may be attached to the cross member 27, and the lower extremity of the loop being urged downwardly by a weight 60 in the form of a cylinder. If desired the ends of the cylinder could be secured to coiled tension springs such as the springs 57 shown in FIGURE 4.

A roller or cylindrical bar non-rotatably mounted, 'as' indicated at 61, may be connected between brackets projecting forwardly from the cross member-27 to support the rearward end of the operative portion-50 of the mat which preferably inclines from front to rear;

It will be noted that in all of the embodiments a portion of the protective member longitudinally spans the opening between the beams 24, cross member 27 and the rearward end of the first or inner part 15 of the superstructure, such portion being of variable length to accommodate advancement of the first or inner part of the superstructure relative to the second or outer part.

Further, it will be noted that any loose roof material which descends onto the upwardly presented face of this portion of the protective member is shed or discarded to the rear of the support as a whole upon advancement of the second or outer part of the superstructure with consequent shortening of the portion of the protective member longitudinally spanning said opening.

The manways 33 and 34 are thus at all times protected from ingress of loose roof material through said opening.

I claim:

1. In a roof support for use in underground mine workings and comprising a base, a plurality of poweroperated extensible props carried thereon, a roof-engaging superstructure, and traction means for advancing the support, the improvement wherein:

(a) said base, props and roof-engaging superstructure define at least one manway extending laterally of said base between said base and said superstructure,

(b) said superstructure includes two parts,

(c) said parts of said superstructure are operably connected with said traction means for relative movement in a direction longitudinally of said base between a first position and a second position,

(d) in said first position said parts of said superstructure extend longitudinally of said base above said manway from one longitudinal boundery thereof to the opposite longitudinal boundary,

(e) in said second position said parts of said superstructure define an opening above said manway,

(f) a protective member is mounted in said opening,

(g) said protective member including a portion presenting a length which varies in conformity with the longitudinal dimension of said opening to span said opening longitudinally during relative movement of said parts of said superstructure from said first position to said second position and thereafter upon attainment of the latter.

2. The structure as defined in claim 1 wherein:

(a) in said second position a first one of said parts of said superstructure occupies a position which is advanced relatively to a second one of said parts,

(b) said opening is defined between the rearward end of said first part and the portion of said second part situated rearwardly of said rear end,

(0) said variable length portion of said protective member is connected operably to said rear end of said first part of said superstructure and extends rearwardly to at least said rear end of said second part of said superstructure.

3. The structure as defined in claim 1 wherein said protective member is formed of flexible sheet material.

4. The structure as defined in claim 2 wherein:

(a) said protective member is formed from a plurality of rigid slat elements,

(b) said slat elements are articulately connected to 7 eachother about axes extending transversely of the J length of said support.

5.. The structure as defined in claim 4 wherein said slat elements are provided with means for rendering said slat elements collectively rigid in a direction longitudinally of said opening with respect to loads imposed by descent of roof material. onto said protective member.

6. The structure as defined in claim 5 wherein said means for renderinghsaidslat elements rigid comprises:

(a) means for eifecting articulated connection between said slat elements,

i (b) stop means' for preventing relative pivotal movement between adjacent slat elements from a position in which said adjacent slat elements are substantially co-planar with each other, and in said direction to rigidify said slat elements collectively with respect to said loads,

(c) said means for effecting articulated connection and said step means in combination providing freedom for said slat elements to pivot relatively in the opposite direction.

7. The structure as defined in claim 5 wherein each slat element has a stop plate rigid therewith and overlapping and abutting the adjacent margin of the next slat element to provide collective rigidity of the slat elements spanning the length of the opening.

8. The structure as defined in claim 1 wherein:

(a) said protective member comprises an operative portion spanning said opening longitudinally,

(b) said protective member further comprises a reserve portion connected to said operative portion and adapted to provide for lengthening thereof as necessary in response to increase in the length of said opening.

9. The structure as defined in claim 8 wherein the reserve portion of the protective member depends from the rearward end of the operative portion.

10. The structure as defined in claims wherein the rear end of the operative portion of the protective member is supported by a cross member at the rearward end of the second part of the superstructure.

11. The structure as defined in claim 8 wherein said reserve portionof said protective member is stored in a compact form, as distinct from an extended form, until taken up and incorporatedjnto the operative portion of the protective member.

12. The structure as defined inclaim 8 wherein said reserve portion is stored in the vform of a roll or folded body having a plurality of downwardly and upwardly extending runs.

13.,The structure as defined in claim 8 wherein said protective member is maintained in a state of longitudinal tension by the reserve portion of the protective member.

14.. The structure as defined in claim 8 wherein said operative portion of said protective member is maintained in a state of longitudinal tension by spring or weight means operatively connected to said reserve portion.

References Cited UNITED STATES PATENTS 2,910,281 10/ 1959 Wilkenloh et a1 6 1-4S 3,399,927 9/ 1968 Groetschel 6l45 X FOREIGN PATENTS 1,010,948 11/ 1965 Great Britain. 1,044,988 6/ 1953 France.

DENNIS L. TAYLOR, Primary Examiner US. Cl. X.R. 248-357