GB2144788A - Mining machine traction unit - Google Patents
Mining machine traction unit Download PDFInfo
- Publication number
- GB2144788A GB2144788A GB08419486A GB8419486A GB2144788A GB 2144788 A GB2144788 A GB 2144788A GB 08419486 A GB08419486 A GB 08419486A GB 8419486 A GB8419486 A GB 8419486A GB 2144788 A GB2144788 A GB 2144788A
- Authority
- GB
- United Kingdom
- Prior art keywords
- machine
- traction unit
- unit
- traction
- mining machine
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
- 238000005065 mining Methods 0.000 title claims abstract description 36
- 229910052500 inorganic mineral Inorganic materials 0.000 claims abstract description 26
- 239000011707 mineral Substances 0.000 claims abstract description 26
- 230000003068 static effect Effects 0.000 claims description 14
- 235000018936 Vitellaria paradoxa Nutrition 0.000 claims 1
- 235000010755 mineral Nutrition 0.000 description 11
- 238000005520 cutting process Methods 0.000 description 6
- 238000006243 chemical reaction Methods 0.000 description 2
- 238000006073 displacement reaction Methods 0.000 description 2
- 230000002028 premature Effects 0.000 description 2
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 description 1
- 230000004913 activation Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 210000000078 claw Anatomy 0.000 description 1
- 239000003245 coal Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 229940072033 potash Drugs 0.000 description 1
- BWHMMNNQKKPAPP-UHFFFAOYSA-L potassium carbonate Substances [K+].[K+].[O-]C([O-])=O BWHMMNNQKKPAPP-UHFFFAOYSA-L 0.000 description 1
- 235000015320 potassium carbonate Nutrition 0.000 description 1
Classifications
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21C—MINING OR QUARRYING
- E21C29/00—Propulsion of machines for slitting or completely freeing the mineral from the seam
- E21C29/04—Propulsion of machines for slitting or completely freeing the mineral from the seam by cable or chains
- E21C29/06—Propulsion of machines for slitting or completely freeing the mineral from the seam by cable or chains anchored at one or both ends to the mine working face
- E21C29/10—Cable or chain co-operating with a winch or the like on the machine
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21C—MINING OR QUARRYING
- E21C29/00—Propulsion of machines for slitting or completely freeing the mineral from the seam
- E21C29/02—Propulsion of machines for slitting or completely freeing the mineral from the seam by means on the machine exerting a thrust against fixed supports
Landscapes
- Engineering & Computer Science (AREA)
- Mining & Mineral Resources (AREA)
- Mechanical Engineering (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Geology (AREA)
- Harvesting Machines For Root Crops (AREA)
Abstract
A traction unit (1) for a shearer type mineral mining machine (2) incorporates a drive sprocket (22) adapted, in use, to drivably engage rack bars (19), the traction unit (1) being independent of the machine (2) and being either attached to the machine (2) by a flexible, load transmitting device (23) or alternatively being capable of engaging at least one abutment carried by the machine, to transmit haulage forces to the machine. The invention also includes a machine (2) provided with at least one such traction unit. <IMAGE>
Description
SPECIFICATION
Shearer type mining machine
This invention relates to a shearer type mining machine, such machines being used extensively for the mining of coal, potash etc.
These machines usually incorporate at least one ranging arm carrying a rotary mineral cutting disc provided with a plurality of cutter picks and operate on the longwall mining principle, being associated with an armoured, scraper chain conveyor built up to the desired length by securing together, end-to-end, the required number of line pans and extending along the mineral face in question. The association is either by being mounted above the conveyor and guided either by the sidewalls of the conveyor or by guide tracks or toe plates attached to the sidewalls, or alternatively mounted beyond the face side of the conveyor and having at least one guidance arm attached to a guidanceltrapping tube or profile in turn attached to the conveyor. In use, the machines are hauled to and fro along the conveyor.In recent times such haulage has been effected on the rack and pinion principle by the so-called "chainless" systems, with at least one traction unit carried by a traction module forming part of the machine body incorporating a drive sprocket which either meshes directly with rack bars or a static chain carried or constrained by the conveyor, or which drives a relatively short, endless chain which in turn meshes with the rack bars. It will be appreciated that when operating on this rack and pinion principle, it is desirable both for effective haulage and for the minimising of wear minimise out-of-pitch problems, whilst it is also necessary to trap the drive sprocket or drive chain into engagement with the rack or static chain to counter the components of the drive force tending to disengage the drive sprocket or drive chain, from the rack or static chain.
However, when the machines are effecting mineral cutting operations, considerable displacement/ vibration is transmitted to the traction module and hence to the drive sprocket or drive chain, from reaction forces on the mineral cutting disc(s). Consequently the drive sprockets or drive chains are rarely maintained in optimum driving relationship with the rack bars or static chain, resulting in an inability to transmit the predicted and/or required haulage forces to the machine and also resulting in premature wear and hence premature replacement of the drive sprockets or drive chain. One proposal to alleviate this problem in a machine of the kind located beyond the face side of the conveyor is disclosed in GB 2081778 A, where the machine body is hinged to the traction units.
According to a first aspect of the present invention, there is provided a traction unit for a shearer type mineral machine, the traction unit incorporating a drive sprocket or a drive chain adapted, in use, to drivably engage rack bars or a static chain, and the traction unit being independent of the machine and being attached to the machine by a flexible, load transmitting device, by which device haulage forces are transmitted to the machine.
The invention also includes a shearer type mining machine incorporting at least one traction unit in accordance with the first aspect of the invention.
According to a second aspect of the present invention, there is provided a traction unit for a shearer type mineral mining machine, the traction unit incorporating a drive sprocket or drive chain adapted, in use, to drivably engage rack bars or a static chain, the traction unit being independent of the machine and capable of engaging at least one abutment carried by the machine, so as to transmit haulage forces to the machine via the abutment.
The invention also includes a shearer type mining machine provided with at least one traction unit in accordance with the second aspect of the invention.
Thus, the traction units in accordance with the first or second aspects of the invention, because they are independent of the machine and are either not attached or are flexibly attached to the machine, can be accurately controlled, thus maintaining optimum engagement conditions between the drive sprocket or drive chain and the rack bars or static chain, so that the designed haulage forces can be transmitted to the machine and so that wear on the drive sprockets or drive chain is minimised, the machine itself still being capable of being displaced by the cutting reaction forces, within the limit of its captivation, with such displacement having no disturbing effect on the positional alignment of the traction unit and its rack bars or static chain.
Machines in accordance with the invention can be provided with one, two, three, or more traction units, depending on the size and hence weight of the machine and consequently the traction forces that it is necessary to apply to the machine to achieve the desired haulage speeds and to meet particular operating conditions e.g. whether the machine is operating a substantially horizontal mineral seam or an inclined mineral seam. Thus a single-ended ranging drum shearer type of machine could be provided with one traction unit, a double-ended ranging drum shearer of say 400 h.p. with three or more traction units.
Furthermore, traction units in accordance with the invention can be mounted either on the face side or the goaf side of the machine for engagement of course with a rack bar or static chain located along the face side or goaf side of the associated conveyor.
Additionally, because the traction units in accordance with the invention are not integrated parts of the machine, a haulage unit requiring servicing, or fault rectification can be removed and replaced by a fresh traction unit, with minimum down-time.
Conventionally, shearer type mining machines are provided with underframes to suit the particular conveyor/operating conditions, and the traction units in accordance with the invention can be mounted either beneath the underframe or at the side of the underframe, so that such units are suitable for relatively small underframes or relatively high underframes.
The traction units in accordance with the invention may operate on a true rack and pinion system i.e. by the drive sprockets directly or indirectly engaging rack bars or static chains, (e.g. via an idler gear) or on the modified rack and pinion principle with the drive sprocket driving a relatively short endless chain e.g.
of the roller link or of the round link types, which endless chain in turn engages the rack bars or more accurately the teeth of the rack bars.
In detail, the traction units may incorporate either electric motors if electric haulage is required, or hydraulic motors if hydraulic haulage is required.
With regard to the first embodiment of the invention, the flexible, load transmitting device may take the form of a chain or wire rope. In detail, each end of the or each traction unit may be flexibly attached to the machine by a short length of chain or wire rope extending between the traction unit and an appropriate fixing point on the machine.
With regard to the second embodiment of traction unit in accordance with the invention, the machine preferably incorporates a pair of abutments to be engaged by opposite ends of the or each traction unit. Alternatively if only one abutment is provided then the machine may be hauled in the reverse direction by attaching a flexible load transmitting device, in accordance with the first aspect of the invention, between the traction unit and the machine. It follows that for machines incorporating, in the preferred arrangement, pairs of abutments, then the number of pairs of abutments provided corresponds to the number of traction units required by that particular machine.
The invention will now be described, in greater detail, by way of examples, with reference to the accompanying drawings, in which:
Figure 1 is a diagrammatic side elevation of a first embodiment of traction unit in accordance with the invention, with part of an associated shearer type mining machine also being illustrated,
Figure 2 is an end elevation of Figure 1;
Figure 3 is a diagrammatic side elevation of a second embodiment of traction unit in accordance with the invention, with part of an associated shearer type mining machine also being illustrated;
Figure 4 is an end elevation of Figure 3;
Figure 5 is a diagrammatic side elevation of a third embodiment of traction unit in accordance with the invention, with part of an associated shearer type mining machine also being illustrated;
Figure 6 is an end elevation of Figure 5;;
Figure 7 is a diagrammatic side elevation of a fourth embodiment of traction unit in accordance with the invention, with part of an associated shearer type mining machine also being illustrated.
Figure 8 is an end elevation of Figure 7;
Figure 9 is a diagrammatic side elevation of a fifth embodiment of traction unit in accordance with the invention, with part of an associated shearer type
mining machine also being illustrated;
Figure 10 is a diagrammatic side elevation of a sixth embodiment of traction unit in accordance with the invention, with part of an associated shearer type mining machine also being illustrated;
Figure ii is an end elevation of Figure 10.
In all Figures, like components are accorded like reference numerals.
In Figures 1 and 2, a traction unit in accordance with the first aspect of the invention is indicated generally at 1, and is intended for use in hauling a shearer type mining machine e.g. a double-ended ranging drum shearer, one end of which is indicated generally at 2 and comprising a machine body -3 made up of various functional modules housing at least one electric motor, a pump module 4 and a gearhead 5 at each end of the machine 2, each gearhead providing an axis of rotation 6 for a ranging arm, indicated partially at 7 and carrying a rotary mineral cutting head (not shown). A similar traction unit is provided at the other end of the machine 2.The mining machine 2 further comprises an underframe 8 which bridges an armoured, scrap enchain conveyor 9 shown seated on a mine floor 10 and comprising a pluraity of conventional line-pans 11 secured together, end to end, in the known articulated manner, to form the conveyor 9 to desired length, the conveyor 9 extending along a longwall mineral face (not shown) from whih webs of mineral are removed by the rotary cutting heads during reciprocable movement of the machine 2 along the conveyor 9 by operation of the traction units 1.In detail, each line pan 11 comprises a face side sidewall 12 spaced from a goaf side sidewall 13 by an interconnecting deck plate 14, with a toe plate 15, constituting one machine guidance track, attached to the face side sidewall 12 and a spill plate 16, constituting another machine guidance track but also serving to trap the machine to the spill plate 16 which is attached to the goaf side sidewall 13. For operative association with the toe plate 15 and spill plate 16, the underframe 8 is provided at its face side with a slide shoe or roller 17 to run on the toe plate 15, and with a slide/trapping shoe 18 to engage the spill plate 16. Attached by bolts to the latter is a rack bar 19 provided with a plurality of rack teeth at regular pitch.
Beyond the rack bar 19 are located the traction units 1 each comprising a rigid outer casing 20 incorporating a hydraulic motor 21 connected by suitable hoses (not shown) to the hydraulic pump module 4, with each motor 21 drivably connected via a transmission (not shown) within the casing 20 terminating in an output, drive sprocket 22 rotatable about a generally horizontal axis and in direct engagement with the teeth of the rack bar 19, the traction units 1 being attached to the underframe 8 by flexible, load transmitting devices in the form of two round link chains 23, of relatively short length, extending between anchor points on the casing 20 and the underframe 8. The traction units 1 are provided with their own guide track 24 attached to the rack bar 19, the guide track comprising a lower guide channel 25 and an upper guide channel 26 interconnected by a support plate 27, with each traction unit 1 provided with a pair of longitudinally spaced apart, lower rollers 28 to run in the guide channel 25, and a pair of longitudinally spaced apart upper rollers 29 to run in the guide channel 26.
Hence activation of the hydraulic motors 21 of the traction units 1, results in torque being applied to the drive sprocket 22, so that the traction units 1 haul themselves, in the appropriate drive direction, along the teeth of the rack bars 19 of adjacent line pans 11, and because of the attachment of the machine 2 to the traction units 1 via the chains 23, the machine 2 is pulled in the appropriate drive direction. It will be appreciated that as the only connection between the traction units 1 and the machine 2 is through the chains 23, the inevitable movements of the machine 2 that occur in use are not transmitted to the traction units 1 and consequently optimum driving relationship of the drive sprockets 22 of the traction units 1 with the teeth of the rack bars 19, is not disturbed.
In the second embodiment, illustrated in Figures 3 and 4, a modified traction unit 1A is shown, in which unit the rollers 29 and 28 of the first embodiment are replaced by an upper slide shoe 29A and a lower slide shoe 28A, to engage the guide channels 25 and 26 respectively.
In the third embodiment, illustrated in Figures 5 and 6 is shown a further modified traction unit 1 B, this time in accordance with the second aspect of the invention, in that the chains 23 of the first and second embodiments are omitted, the underframe 8 being provided with downwardly depending abutments 30, spaced apart longitudinally of the underframe 8 (and of the conveyor 9), buy a distance corresponding to the distance between a pair of bearing surfaces 20A of casing 20B of traction unit 1 B, whereby haulage forces from the both traction units 1 B are transmitted to the underframe 8 via the pairs of abutments 30, in the desired haulage direction.Also in this embodiment, trapping or captivation of the underframes, is effected by providing a modified spill plate 16B with a circular trapping bar 33, for engagement by an appropriately profiled shoe 18B pivotally attached to the underframe at 34, while a modified support plate 27B is also provided with a circular trapping bar 36, for engagement by an appropriately profiled claw 37 of the underframe 8. It will again be appreciated that as the only connection between the traction units 1 and the machine 2 is by engagement between surfaces 20A of the casings 20B and the adjacent abutment 30, movements of the machine 2 are not transmitted to the traction units 1 and consequently optimum driving relationship of the drive sprockets 22 of the traction units 1 with the teeth of the rack bars 19, is not disturbed.
In the fourth embodiment, illustrated in Figures 7 and 8, is shown a second embodiment of traction unit 1C in accordance with the second aspect of the invention, with casing 20C provided with bearing surfaces 20Ato engage abutments 20. In contrast to the third embodiment, this fourth embodiment is provided with slide shoes 29C, 28C.
In the fifth embodiment, illustrating Figure 9, is shown in traction unit 1 D in which the drive sprocket 22 is rotatable about an upright axis (in contrast to rotation about a horizontal axis, as illustrated in the embodiments of Figures 1 to 8). With this fifth embodiment, the traction unit 1 D is again in accordance with the second aspect of the invention, in that the traction unit 1D is engageable with downwardly depending abutments of the underframe 8, while in contrast with the embodiments illustrated in Figures 2 and 4, the guide track 24 is adjacent the spill plate 16, whilst the rack bar 19 is remote from the spill plate 16.
In the sixth embodiment, illustrated in Figures 10 and 11, is shown a further example of traction unit 1 E in accordance with the second aspect of the invention. However, with this embodiment, the rack bar 19 is remote from the spill plate 16.
Claims (34)
1. Atraction unit for a shearer type mineral mining machine, the traction unit incorporating a drive sprocket or a drive chain adapted, in use, to drivably engage rack bars or a static chain, and the traction unit being independent of the machine and being attached to the machine by a flexible, load transmitting device, by which device haulage forces are transmitted to the machine.
2. A traction unit for a shearer type mineral mining machine, the traction unit incorporating a drive sprocket or drive chain adapted, in use, to drivably engage rack bars or a static chain, the traction unit being independent of the machine and capable of engaging at least one abutment carried by the machine, so as to transmit haulage forces to the machine via the abutment.
3. Ashearertype mining machine incorporating at least one traction unit as defined in Claim 1.
4. A shea rer type mining machine provided with at least one traction unit as defined in Claim 2.
5. A machine as Claimed in Claim 3 or Claim 4, provided with one, two, three, or more traction units.
6. A single-ended ranging drum shearertypeof machine as claimed in Claim 3 or Claim 4, provided with one traction unit.
7. A double-ended ranging drum shearer type of machine as claimed in Claim 3 or Claim 4, provided with three or more traction units.
8. A machine as Claimed in any one of Claims 3 to 7, wherein the traction unit(s) is or are mounted on the face of the machine.
9. A machine as Claimed in any one of Claims 3 to 7, wherein the traction unit(s) is or are mounted on the goaf side of the machine.
10. A machine as claimed in any preceding
Claim, wherein the traction unit(s) is mounted beneath an underframe of the machine.
11. A machine as claimed in any one of Claims 1 to 9, wherein the traction unit(s) is mounted at the side of an underframe of the machine.
12. A machine as claimed in any preceding Claim wherein the traction unit(s) comprises at least one drive sprocket engageable directly or indirectly with a rack bar or a static chain.
13. A machine as claimed in any one of Claims 1 to 11, wherein the traction unit(s) comprises a relatively short endless chain engageable with a rack bar or static chain.
14. A machine as claimed in Claim 13, wherein the endless chain is of the roller link type.
15. A machine as claimed in Claim 13, wherein the endless chain is of the round link type.
16. A machine as claimed in any preceding
Claim, wherein the traction unit(s) incorporates an electric motor.
17. A machine as claimed in any one of Claims 1 to 15, wherein the traction unit(s) incorporates an hydraulic motor.
18. A traction unit as claimed in Claim 1, and any
Claim appendant thereto, wherein the flexible, load transmitting device takes the form of a chain.
19. Atraction unit as claimed in Claim land any
Claim appendant thereto, wherein the flexible, load transmitting device takes the form of a wire rope.
20. A machine as claimed in Claim 3, and any
Claim appendant thereto, flexibly attached to a traction unit as defined in Claim land any Claim appendant thereto, by a relatively short length of chain or wire rope constituting the flexible, load transmitting device and extending between the traction unit(s) and an appropriate fixing point on the machine.
21. A traction unit as claimed in Claim 2, and any
Claim appendantthereto, associated with a mining machine as claimed in Claim 4, and any Claim appendant thereto, with the machine incorporating a pair of abutments to be engaged by opposite ends of the traction unit(s).
22. A traction unit as claimed in Claim 2, and any
Claim appendantthereto, associated with a mining machine as claimed in Claim 4, and any Claim appendant thereto, the machine incorporating an abutment, to be engaged by one end of the traction unit(s) for haulage of the machine in a first direction, with the machine hauled in the reverse direction by attaching a flexible, load transmitting device between the traction unit and the machine.
23. Atraction unit for a shearer type mineral mining machine, the unit being substantially as hereinbefore described with reference to Figures 1 and 2 of the accompanying drawings.
24. A traction unit for a shearer type mineral mining machine, the unit being substantially as hereinbefore described with reference to Figures 3 and 4 of the accompanying drawings.
25. Atraction unitfora shearertype mineral mining machine, the unit being substantially as herein before described with reference to Figures 5 and 6 of the accompanying drawings.
26. Atraction unitfora shearer type mineral mining machine, the unit being substantially as hereinbefore described with reference to Figures 7 and 8 of the accompanying drawings.
27. A traction unit for a shearer type mineral mining machine, the unit being substantially as hereinbefore described with reference to Figure 9 of the accompanying drawings.
28. A traction unit for a shearer type mineral mining machine, the unit being substantially as hereinbefore described with reference to Figures 10 and 11 of the accompanying drawings.
29. A shearer type mineral mining machine, substantially as hereinbefore described with reference to Figures 1 and 2 of the accompanying drawings.
30. Ashearertype mineral mining machine, substantially as hereinbefore described with reference to Figures 3 and 4 of the accompanying drawings.
31. Ashearertype mineral mining machine, substantially as herein before described with reference to Figures 5 and 6 of the accompanying drawings.
32. Ashearertype mineral mining machine, substantially as hereinbefore described with reference to Figures 7 and 8 of the accompanying drawings.
33. Ashearertype mineral mining machine, substantially as hereinbefore described with reference to Figure 9 of the accompanying drawings.
34. A shearer type mineral mining machine, substantially as hereinbefore described with reference to Figures 10 and 11 of the accompanying drawings.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB838321490A GB8321490D0 (en) | 1983-08-10 | 1983-08-10 | Shearer-type mining machine |
Publications (2)
Publication Number | Publication Date |
---|---|
GB8419486D0 GB8419486D0 (en) | 1984-09-05 |
GB2144788A true GB2144788A (en) | 1985-03-13 |
Family
ID=10547085
Family Applications (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB838321490A Pending GB8321490D0 (en) | 1983-08-10 | 1983-08-10 | Shearer-type mining machine |
GB08419486A Withdrawn GB2144788A (en) | 1983-08-10 | 1984-07-31 | Mining machine traction unit |
Family Applications Before (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB838321490A Pending GB8321490D0 (en) | 1983-08-10 | 1983-08-10 | Shearer-type mining machine |
Country Status (1)
Country | Link |
---|---|
GB (2) | GB8321490D0 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20120104832A1 (en) * | 2010-10-29 | 2012-05-03 | Niederriter Edward F | Drive mechanism for a longwall mining machine |
-
1983
- 1983-08-10 GB GB838321490A patent/GB8321490D0/en active Pending
-
1984
- 1984-07-31 GB GB08419486A patent/GB2144788A/en not_active Withdrawn
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20120104832A1 (en) * | 2010-10-29 | 2012-05-03 | Niederriter Edward F | Drive mechanism for a longwall mining machine |
US8789892B2 (en) * | 2010-10-29 | 2014-07-29 | Joy Mm Delaware, Inc. | Drive mechanism for a longwall mining machine |
Also Published As
Publication number | Publication date |
---|---|
GB8321490D0 (en) | 1983-09-14 |
GB8419486D0 (en) | 1984-09-05 |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
WAP | Application withdrawn, taken to be withdrawn or refused ** after publication under section 16(1) |