US2198163A - Method of and apparatus for mining, quarrying, and the like - Google Patents

Method of and apparatus for mining, quarrying, and the like Download PDF

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US2198163A
US2198163A US211299A US21129938A US2198163A US 2198163 A US2198163 A US 2198163A US 211299 A US211299 A US 211299A US 21129938 A US21129938 A US 21129938A US 2198163 A US2198163 A US 2198163A
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roof
coal
face
undercut
cut
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US211299A
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Gullick Geoffrey Merton
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Mavor and Coulson Ltd
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    • EFIXED CONSTRUCTIONS
    • E21EARTH DRILLING; MINING
    • E21DSHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
    • E21D17/00Caps for supporting mine roofs
    • EFIXED CONSTRUCTIONS
    • E21EARTH DRILLING; MINING
    • E21CMINING OR QUARRYING
    • E21C25/00Cutting machines, i.e. for making slits approximately parallel or perpendicular to the seam
    • E21C25/22Machines slitting solely by one or more cutter chains moving unidirectionally along jibs
    • E21C25/24Machines slitting solely by one or more cutter chains moving unidirectionally along jibs with flat jibs only

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  • a method, known as fore-timbering or forepoling, sometimes used in coal mining for supporting the roof at the coal' face comprises drilling holes in the face at the roof level to a greater depth than the depth to which the coal is about to be removed, inserting one end of a roof beam intothe hole and supporting the beam at its outer end by means of a ⁇ prop, the beams being upheld, during and after breaking down of' the '0 coal, by their engagement with the inner extremities of the holes. however, limited in its application because of its expense.
  • the present invention refers to a method of l5 mining, quarrying and the like which provides in an improved manner for fore-poling and which fenables drilling of the face, hereinafter assumed to be a coal face, and shot firing to be eliminated, allows the breaking down of the coal to be ⁇ controlled and provides for its being readily handled mechanically at the position where it is broken down.
  • two cuts are made in the coal face, an undercutat or near the floor level and a roof cut at or near the roof ⁇ level,
  • roof beams are then inserted into the roof cut so that their inner ends reach beyond the depth of the undercut, theroof beams are supported in frontof the coal face by Props or the like, and
  • the coal between theundercut and the roof cut is broken off, the extra depth of the roof cut leaving a shelf or ledge on which the inner ends of the roo-f beams rest while, and after, the coal is broken, thus securing the roof.
  • breaking may be eiected by the application of downward pressure to it o within ⁇ the roof cut, for example, by hydraulic pressure, or breaking maybe effected by the application of upward pressure within the undercut.
  • breaking is ⁇ under control in ⁇ that the coal is not scattered asitwould be, for example, as a result of shot firing.
  • a face conveyor may be assembled on the face side of the rowfo'f props supporting the outer l5() ends of the roof beamsand a mechanical loader be operated between the-conveyor and the new coal face to load the broken coal on to the face conveyor.
  • a cutting machine having two cutter l members, for example, cutter chains, adapted to operate simultaneously one above the other at a substantial distance apart vertically and the upper of which when in the normal cutting position has a greater cutting reach than the 10 lower. It is desirable that ina machine of this nature the arrangement should be such that the lower cutting member cuts in advance of the upper cutter member, as better breakage of the coal from the coal face results.
  • This feature of one ll cutter member cutting in advance of another is known in itself, its embodiment in a machine having equal undercutting and overcutting members being disclosed in the specification of United States Patent No. 1,979,694, granted to W. A. n
  • a machine may be so constructed that the lead (or degree of advance) of the lower cutter member Il relative to the upper cutter member can be adjusted from a Zero position (i. e. where there is no lead) to a maximum amount allowed for in the construction of the machine.
  • FIGS 1, 2, 3, 4, 5 and 6 illustrate diagrammatically successive stages in the method of minlng
  • FIG. 7 is a side elevation and Figure 8 is an 35 end elevation showing a first example of coal cutting machine for use in the method in accordance with the invention
  • Figure 9 is a side elevation and Figure 10 is an end elevation showing a second example of coal- 40 cutting machine
  • Figure l1 shows a detail.
  • the diagrams are ⁇ vertical sections at right angles ⁇ to the coal face and show coal face A, packing B, a face conveyor C, and a coal cutting machine D.
  • this invention provides for the formation of ⁇ a shelf or ledge in the coal face at or near the roof level to carry the inner ⁇ ends of roof beams while and after the coal.- below is broken.
  • a mass yof coal has just been removed in accordance with the invention, leaving a ledge I in the new face A supporting the innerends .of
  • roof beams 2 the, outer ends of which are supu ported by a row of props 3, each of which has a. laterally projecting bracket for that purpose.
  • a fresh row of props is now set up at @with their brackets under and just clear of' the roof beams 2.
  • rl'lne coal cutting machine D having an under-, cutting jib 5 and an overcutting jib 6, the latter of greater cuttingreach than the former, now cuts along thev face, see Figure 2, forming an undercut and a roof cut of greater depth than the undercut, say 4 feet 6 inches deep in the one The coal which has been overcut and undercut tends.
  • laterally extending cantilever conveyor partB is now advanced into the broken coal F, see Figure G, and loads it into the face conveyor C, leaving thel new ⁇ face A1 clear, as shown in Figure 5 in which the conditions are virtually a repetition of the conditions shown in Figure l. The process can then be repeated.
  • Figures '7 and 8 show' a coal cutting machine D having ⁇ two superimposed cutter-chain jibs 5. and 6, one for undercutting and the other for roof cutting.
  • the undercutting jib. 5 is' arranged to cut in advance of the over-cutting jib it while the overcutting jib li. has agreater cuttingl reach than the undercutting jibi 5.
  • Bothcutter-chains are driven from one and the ⁇ same motor in the body or the machine and the machine is adapted to beadvanced by haulage means, the drum 9 of which is shown.
  • the overcutting jib 6 is carried'by a turret structure iwhich permits of adjustment of its height.
  • Figures 9 and 10 show a machine having provision whereby the lead of the lower cutter-member relative to the upper ⁇ cutter member can.
  • This machine is made uptof a first machine element D1, whichA comprises ⁇ a body complete with motoncuttermember 51 forl undercutting, and haulage means, and -a-,secondmachine element D2 mountedupon the iirstelement Dl and comprising a separate body complete with motor, cutter member 61 for overcutting, and haulage means.
  • the lower element'D1 has two parallel longitudinal bars II ⁇ upon it, one at or near each side, see Figure 10.
  • the upper element D2 is carriedby'means of fourisorew jacks I2 the feet of which engage with a plate I3 resting upon the longitudinalbars II, and the upper element D2 with the jacks I2, plate I3 and bars I I can be slid longitudinally upon the lower element D1, provisionl being made.y for. holding. them.Il atl any desired position of adjustment, for example, by means of screw clamps (not shown). In some cases there may be screw mechanism for effecting the longitudinal movement, which will serve to hold the upper element at the longitudinal posi'- tion desired.
  • the height of the overcutting member relative to the base of the machine can be varied and by operating the jacks differentially the upper element can be inclined relative to the lower element, the connection of the jacks, top and bottom, being arranged to allow of such movement. Provision may be made for effecting any or all of the adjustments by power from one or other of the motors ofthe machine, or by hand.
  • Figure 11 ⁇ shows the top of a steel mine post of H-section with two welded-on brackets I4, one at each side, for the support of roof beams.
  • Amachine for simultaneous undercutting and roof cutting may be of the cutter-chain type
  • cutter-bar type or of disc type, or a combination of 'any two of these types.
  • the method of mining comprising making two cuts in the coal face, an undercut at or near the door level and a roof cut at or near the roof level, the roof out being made of a greater ydepth inwards from the face than the undercut, insertn ing roof beams intothe roof cut so that their ⁇ inner ends reach beyond the depth of the undercut, supportingthe roof beams in front of the coal face by props vor, the like, and breaking on the coal between the undercut and the roof cut, the extra depth ofthe roof cut leaving a ledge on which the inner ends of the roof beams rest while and after the coal is broken, thus securing the roof.
  • the method of mining comprising making two cutsin the coalv face, an undercut at or near theiioor level and a roofcut at or near the roof level, the roof cut being made of'a greaterdepth inwards from the face than the undercut, inserting roof beams. into theroof cut so thattheir inner ends reach beyond'the depth of the' undercut, supporting the roof beams in front of the coal face'by props or the like,.breakingroff the' coalr between .the undercut and the roof cut, the extra depth of theroof cut leaving; a ledge' on which the inner ends.
  • the method of mining comprising ⁇ making two cutssimultaneously iny thecoalface, an undercut at or near thev floor level and a roof cut at or near the roof level, the roof cut being made of a greater depth vinwards from the ⁇ face ythan .the undercut, inserting roof beamsinto the roof. cut so that their inner ends reachbeyondthe depth of the undercut, supportingthe roof beams.v in front ofthe coal face by props or the like, and breaking off thevcoal between theundercut and the roof cut, the extra depth of the roofcut leaving-a ledge on which the'inner ⁇ ends of the roof beams rest Vwhile and after the coal is broken, thus securing the roof.VY y v 4.
  • the methodof miningV comprising making two cuts simultaneously in the coal face, an undercut at or near the oor level and aroof'cut at or. near the roof level, the roof cut vbeing made offa greaterzdepth inwards-.from the face than the undercut, inserting roof beams into the roof out so that their inner ends reach beyond the depth of the undercut, supporting the roof beams' in iront of the coal face by props or ⁇ the like,
  • a coal cutting ⁇ machine having a machine i body adapted for movement along a coal face
  • the twocutter members when in the normal cutting ⁇ position having a greater cutting reach than the lower to make the-roof cut of a greater depth inwards from the face than the undercut, and the twocutter members being relatively movable longitudinally for adjusting the lower cutter member to out in advance of the upper cutter member to a degree variable ⁇ from 'a maximum allowed for in the construction of the machine to zero, with means for securing the cutter members inposition as adjusted.
  • a coal cutting machine having a machine Abody to be moved along a coal face, two cutter members projecting from said body, one above the other, to make an undercut and a roof cut in the face simultaneously, haulage means for moving the machine alongthe coal face, motor means 4for driving the said haulage means and the said ⁇ cutter members, the upper of the two cutter members when in the normal cutting position having a greater cutting reach than the lower tc mak-e the roof ⁇ cut of a greater depth inwards means iorsecuring the cutter members in position as adjusted.

Description

Apri] 23, 1940. G. M. GuLLlcK 2 Sheets-Sheet 1 Filed June 1. 19:58
April 23, 1940.
G. M; GuLLlcK METHOD OF' AND APPARATUS FOR MINING, QUARRYING, AND TH Filed June l. 1938 E LIKE 2 Sheets-Sheet 2 By awww.
, Patented Apr. 23, 1940 PATENT OFFICE L METHOD oF AND APPARATUS Fon MINING,
' QUARRYING, AND THE LIKE G'coirey Merton Gullick, Glasgow, Scotland, assignor to Mavor and Coulson, Limited,fGlasgow, Scotlandl Application June 1, 1938, Serial No. 211,299 In Greatritain June 12, 1937 t f f l `e claims. -(c1. 2oz-1) A method, known as fore-timbering or forepoling, sometimes used in coal mining for supporting the roof at the coal' face comprises drilling holes in the face at the roof level to a greater depth than the depth to which the coal is about to be removed, inserting one end of a roof beam intothe hole and supporting the beam at its outer end by means of a` prop, the beams being upheld, during and after breaking down of' the '0 coal, by their engagement with the inner extremities of the holes. however, limited in its application because of its expense.
"The present invention refers to a method of l5 mining, quarrying and the like which provides in an improved manner for fore-poling and which fenables drilling of the face, hereinafter assumed to be a coal face, and shot firing to be eliminated, allows the breaking down of the coal to be `controlled and provides for its being readily handled mechanically at the position where it is broken down.
According to this invention, two cuts are made in the coal face, an undercutat or near the floor level and a roof cut at or near the roof` level,
the roof cut being made of a greater depth inwards from the face than the undercut, roof beams are then inserted into the roof cut so that their inner ends reach beyond the depth of the undercut, theroof beams are supported in frontof the coal face by Props or the like, and
the coal between theundercut and the roof cut is broken off, the extra depth of the roof cut leaving a shelf or ledge on which the inner ends of the roo-f beams rest while, and after, the coal is broken, thus securing the roof.
If the coal is such that, after cutting, it does not break ofi of itself, breaking may be eiected by the application of downward pressure to it o within `the roof cut, for example, by hydraulic pressure, or breaking maybe effected by the application of upward pressure within the undercut. In this way, coal can be mined without drilling and without shot ring, and the breaking is `under control in `that the coal is not scattered asitwould be, for example, as a result of shot firing.
A face conveyor may be assembled on the face side of the rowfo'f props supporting the outer l5() ends of the roof beamsand a mechanical loader be operated between the-conveyor and the new coal face to load the broken coal on to the face conveyor. l
It ispreferred that the undercut and the deeps er 'roof cut shouldbe made simultaneously,vbut
'Ihis method` of workingis,
they may be made separately, in which latter case the undercut should as a rule be made iirst. For simultaneously making an undercut and a roof cut, there is provided in accordance with this .Y invention a cutting machine having two cutter l members, for example, cutter chains, adapted to operate simultaneously one above the other at a substantial distance apart vertically and the upper of which when in the normal cutting position has a greater cutting reach than the 10 lower. It is desirable that ina machine of this nature the arrangement should be such that the lower cutting member cuts in advance of the upper cutter member, as better breakage of the coal from the coal face results. This feature of one ll cutter member cutting in advance of another is known in itself, its embodiment in a machine having equal undercutting and overcutting members being disclosed in the specification of United States Patent No. 1,979,694, granted to W. A. n
Logan. A
In this connection, in accordance with a further feature of the present invention, a machine may be so constructed that the lead (or degree of advance) of the lower cutter member Il relative to the upper cutter member can be adjusted from a Zero position (i. e. where there is no lead) to a maximum amount allowed for in the construction of the machine. l
The invention will nowbe described with rei- 30 erence tothe accompanying drawings, in which:
Figures 1, 2, 3, 4, 5 and 6 illustrate diagrammatically successive stages in the method of minlng,
` Figure, 7 is a side elevation and Figure 8 is an 35 end elevation showing a first example of coal cutting machine for use in the method in accordance with the invention,
` Figure 9 is a side elevation and Figure 10 is an end elevation showing a second example of coal- 40 cutting machine, and
Figure l1 shows a detail.
The diagrams are `vertical sections at right angles `to the coal face and show coal face A, packing B, a face conveyor C, and a coal cutting machine D. l
As has already been explained, this invention provides for the formation of `a shelf or ledge in the coal face at or near the roof level to carry the inner `ends of roof beams while and after the coal.- below is broken. In Figurel, it is assumed that a mass yof coal has just been removed in accordance with the invention, leaving a ledge I in the new face A supporting the innerends .of
roof beams 2, the, outer ends of which are supu ported by a row of props 3, each of which has a. laterally projecting bracket for that purpose. A fresh row of props is now set up at @with their brackets under and just clear of' the roof beams 2. rl'lne coal cutting machine D, having an under-, cutting jib 5 and an overcutting jib 6, the latter of greater cuttingreach than the former, now cuts along thev face, see Figure 2, forming an undercut and a roof cut of greater depth than the undercut, say 4 feet 6 inches deep in the one The coal which has been overcut and undercut tends. to break downon to the vertical plane Dxtending upwards from the inner extremity oi the undercut, see Figure 4, in many cases coming down of its own accord, but if necessary being brought down by the use in either of the cuts of a hydraulic coal burster, similar to apparatus at present used for breaking down undercut coal by insertion into a hole drilled in the co-al face above lthe cut. The inner end of the roof bea-n1 2 is left supportedv on a ledge I 2 correspondingwith the ledge I initially assumed to exist in Figure 1. The position is now as shown in Figures 4 and 6. A mechanical loader E, shown as being of the known type with oscillating gatheringarms 'I and a rearwardly and'. laterally extending cantilever conveyor partB is now advanced into the broken coal F, see Figure G, and loads it into the face conveyor C, leaving thel new` face A1 clear, as shown in Figure 5 in which the conditions are virtually a repetition of the conditions shown in Figure l. The process can then be repeated.
Figures '7 and 8 show' a coal cutting machine D having `two superimposed cutter-chain jibs 5. and 6, one for undercutting and the other for roof cutting. The undercutting jib. 5 is' arranged to cut in advance of the over-cutting jib it while the overcutting jib li. has agreater cuttingl reach than the undercutting jibi 5. Bothcutter-chains are driven from one and the` same motor in the body or the machine and the machine is adapted to beadvanced by haulage means, the drum 9 of which is shown. The overcutting jib 6 is carried'by a turret structure iwhich permits of adjustment of its height.
Figures 9 and 10 show a machine having provision whereby the lead of the lower cutter-member relative to the upper` cutter member can. be
' adjusted from a Zeroi positionto1 a maximum amount allowed for in the construction of the machine. This machine is made uptof a first machine element D1, whichA comprises` a body complete with motoncuttermember 51 forl undercutting, and haulage means, and -a-,secondmachine element D2 mountedupon the iirstelement Dl and comprising a separate body complete with motor, cutter member 61 for overcutting, and haulage means. The lower element'D1 has two parallel longitudinal bars II `upon it, one at or near each side, see Figure 10. The upper element D2 is carriedby'means of fourisorew jacks I2 the feet of which engage with a plate I3 resting upon the longitudinalbars II, and the upper element D2 with the jacks I2, plate I3 and bars I I can be slid longitudinally upon the lower element D1, provisionl being made.y for. holding. them.Il atl any desired position of adjustment, for example, by means of screw clamps (not shown). In some cases there may be screw mechanism for effecting the longitudinal movement, which will serve to hold the upper element at the longitudinal posi'- tion desired. By equal operation of the jacks, the height of the overcutting member relative to the base of the machine can be varied and by operating the jacks differentially the upper element can be inclined relative to the lower element, the connection of the jacks, top and bottom, being arranged to allow of such movement. Provision may be made for effecting any or all of the adjustments by power from one or other of the motors ofthe machine, or by hand.
Figure 11` shows the top of a steel mine post of H-section with two welded-on brackets I4, one at each side, for the support of roof beams.
Amachine for simultaneous undercutting and roof cutting, may be of the cutter-chain type,
the cutter-bar type, or of disc type, or a combination of 'any two of these types.
I claim:
l. The method of mining comprising making two cuts in the coal face, an undercut at or near the door level and a roof cut at or near the roof level, the roof out being made of a greater ydepth inwards from the face than the undercut, insertn ing roof beams intothe roof cut so that their`inner ends reach beyond the depth of the undercut, supportingthe roof beams in front of the coal face by props vor, the like, and breaking on the coal between the undercut and the roof cut, the extra depth ofthe roof cut leaving a ledge on which the inner ends of the roof beams rest while and after the coal is broken, thus securing the roof.
2L The method of mining comprising making two cutsin the coalv face, an undercut at or near theiioor level and a roofcut at or near the roof level, the roof cut being made of'a greaterdepth inwards from the face than the undercut, inserting roof beams. into theroof cut so thattheir inner ends reach beyond'the depth of the' undercut, supporting the roof beams in front of the coal face'by props or the like,.breakingroff the' coalr between .the undercut and the roof cut, the extra depth of theroof cut leaving; a ledge' on which the inner ends. oftheroof beams rest while and afterv the coal is broken, vthusrsecuring the roof, assembling a face conveyor on the face sideof therow of props.- supporting the outer `ends of the roof beams, and operating a mechanical loader between the. conveyor and, the new coal face, to yload thel broken coal on tothe face conveyor.
3. The method of mining comprising` making two cutssimultaneously iny thecoalface, an undercut at or near thev floor level and a roof cut at or near the roof level, the roof cut being made of a greater depth vinwards from the `face ythan .the undercut, inserting roof beamsinto the roof. cut so that their inner ends reachbeyondthe depth of the undercut, supportingthe roof beams.v in front ofthe coal face by props or the like, and breaking off thevcoal between theundercut and the roof cut, the extra depth of the roofcut leaving-a ledge on which the'inner `ends of the roof beams rest Vwhile and after the coal is broken, thus securing the roof.VY y v 4. The methodof miningV comprising making two cuts simultaneously in the coal face, an undercut at or near the oor level and aroof'cut at or. near the roof level, the roof cut vbeing made offa greaterzdepth inwards-.from the face than the undercut, inserting roof beams into the roof out so that their inner ends reach beyond the depth of the undercut, supporting the roof beams' in iront of the coal face by props or`the like,
breaking off the coal between the undercut and the roof out, the extra depth oi the roof out leav-` ing a ledge on which the inner ends of the roof beams rest while and after the'coal is broken,
thus securing the roof, assembling a face oonveyor on the face side of the `row of props supporting the outer fends of thereof beams, and operating a mechanical loader between the conveyor and the new coal face, to load the broken coalon to the face conveyor.
5. A coal cutting `machine having a machine i body adapted for movement along a coal face,
two cutter members projecting from saidfbody,
one above theother, to `make an undercut and a roof out` inthe ace simultaneously, motor means for driving the said cutter members, the
upperor the two cutter members when in the normal cutting `position having a greater cutting reach than the lower to make the-roof cut of a greater depth inwards from the face than the undercut, and the twocutter members being relatively movable longitudinally for adjusting the lower cutter member to out in advance of the upper cutter member to a degree variable` from 'a maximum allowed for in the construction of the machine to zero, with means for securing the cutter members inposition as adjusted.
6. A coal cutting machine having a machine Abody to be moved along a coal face, two cutter members projecting from said body, one above the other, to make an undercut and a roof cut in the face simultaneously, haulage means for moving the machine alongthe coal face, motor means 4for driving the said haulage means and the said `cutter members, the upper of the two cutter members when in the normal cutting position having a greater cutting reach than the lower tc mak-e the roof `cut of a greater depth inwards means iorsecuring the cutter members in position as adjusted.
GEOFFREY MERTON GULLICK.
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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2677535A (en) * 1950-02-17 1954-05-04 Paul V Malloy Mine roof support beam with wall drilling end
US2716025A (en) * 1951-07-17 1955-08-23 Paul V Malloy Method and mining apparatus with movable roof supports
US2945686A (en) * 1956-11-23 1960-07-19 Jeffrey Mfg Co Mining machine having means for cutting side wall holes for roof timbers

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2677535A (en) * 1950-02-17 1954-05-04 Paul V Malloy Mine roof support beam with wall drilling end
US2716025A (en) * 1951-07-17 1955-08-23 Paul V Malloy Method and mining apparatus with movable roof supports
US2945686A (en) * 1956-11-23 1960-07-19 Jeffrey Mfg Co Mining machine having means for cutting side wall holes for roof timbers

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