Title of Invention

"A DEVICE FOR LOADING BLASTED COAL FROM THE WORKING FACE IN CONVENTIONAL LONGWALL MINING"

Abstract

A device for loading blasted coal from the working face in conventional longwall mining, which comprises a pair of working implements(17), such as loading buckets, each of the said segment consists in combination a Bull gear (2) mounted on a powered shaft (21) on which a flat face cam - follower (3, 4) and a pinion (5) are also mounted, the said Bull gear (2) being provided with a coaxial bevel gear (1) and crank (12) so as to provide adjustable forward and backward stroke through a slider link (9) in a slot in a pivoted (11) rocker arm/slotted lever (10), non-pivoted end of the said rocker arm/slotted lever (10) being connected through a link (13) enabling transmission of the forward and backward movement through a ram (14) in a casing (18), a L-shaped link (16) and a guided link (15) to a working implement, such as the loading bucket (17), the ram (14) in the casing (18) being mounted perpendicularly with the flat face follower (4) enabling vertical reciprocating movement, the said ram (14) in the said casing (18) being supported with a rack and pinion (19) arrangement at the non-working end, the said shaft (21) being powered through the said shaft mounted pinion (5) being coupled with a spur gear (6) of a gearbox (7) connected to a prime mover, such as a motor (8).

Full Text

This invention relates to a device for loading blasted coal from the working face in conventional longwall mining. This invention particularly relates to a device useful for underground coal mines more particularly in conventional longwall panel with blasted coal face for gathering loose coal from the working face to the running chain conveyor. In general, in conventional longwall panel, coal is extracted by blasting the face and then loose coal is transferred by manual shoveling process from working face to the running chain conveyor which is very much time consuming, costly, as a large contingent of work force is involved in the process and at the same time hazardous to the workers from health point of view. At present no such intermediate low cost, easy to handle equipment are available which can eliminate the above problems and increase the productivity which is the main objective of the Indian coal mining industry. In this context reference may be made to US patent no. 6,672,674 B2, in which an advancing support equipment and a face conveyor which is parallel to the direction of mining, coupled with it as well as one boring device for the production of shot holes and a loading device driven perpendicularly to the direction of mining to supply the face conveyor with the blasted rock. This makes the device heavy and bulky. From the drawing and literature as described in the patent one can assume that the operation of the machine is either hydraulically or pneumatically operated. All this makes the device very expensive. At the same time since device moves parallel to the direction of the conveyor for loading the blasted ore, swinging long boom is required, which needs more working space and also makes the operation more time consuming which ultimately affects the rate of transfer of blasted ore from the face to conveyor. Also from operation it is evident that loading machine shovels blasted rock / ore from the face and discharges them to the perpendicularly run face conveyor in which there is always a possibility that entire rocks / ore may not be transfer to the face conveyor. This invention relates to a device for loading blasted coal from the working face in conventional longwall mining. This invention particularly relates to a device useful for underground coal mines more particularly in conventional longwall panel with blasted coal face for gathering loose coal from the working face to the running chain conveyor. In general, in conventional longwall panel, coal is extracted by blasting the face and then loose coal is transferred by manual shoveling process from working face to the running chain conveyor which is very much time consuming, costly, as a large contingent of work force is involved in the process and at the same time hazardous to the workers from health point of view. At present no such intermediate low cost, easy to handle equipment are available which can eliminate the above problems and increase the productivity which is the main objective of the Indian coal mining industry. In this context reference may be made to US patent no. 6,672,674 B2, in which an advancing support equipment and a face conveyor which is parallel to the direction of mining, coupled with it as well as one boring device for the production of shot holes and a loading device driven perpendicularly to the direction of mining to supply the face conveyor with the blasted rock. This makes the device heavy and bulky. From the drawing and literature as described in the patent one can assume that the operation of the machine is either hydraulically or pneumatically operated. All this makes the device very expensive. At the same time since device moves parallel to the direction of the conveyor for loading the blasted ore, swinging long boom is required, which needs more working space and also makes the operation more time consuming which ultimately affects the rate of transfer of blasted ore from the face to conveyor. Also from operation it is evident that loading machine shovels blasted rock / ore from the face and discharges them to the perpendicularly run face conveyor in which there is always a possibility that entire rocks / ore may not be transfer to the face conveyor. Besides the drawbacks as noted above in respect of the US patent no. 6,672,674 B2, in India, conventional longwall panels with blasted coal face runs on different methodology. In this method shot holes in faces are made perpendicularly of the running face conveyor. Thus this machine may not be useful in Indian mining condition. At the same time since side-loading shovel is used, here gathering of ore is basically scooping process, in which, in-fact there is possibility of some broken ore remains and not entire broken ore may not be transferred into the conveyor. In view of the above, it is apparent that there is a definite need to provide a device for gathering blasted loose coal from the working face in conventional longwall in underground coal mines. The main object of the present invention is to provide a device for loading blasted coal from the working face in conventional longwall mining, which will help obviate the drawbacks as set forth above. Another object of the present invention is to provide a device useful for underground coal mines more particularly in conventional longwall panel with blasted coal face for gathering loose coal from the working face to the running chain conveyor. Still another object of present invention is to provide a mechanized device which can get blasted coal from the face to the running chain conveyor in minimum time thus increasing the productivity using less amount of man power and cutting short the loose coal collecting time. In the present invention there is provided a device for loading blasted coal from the working face in conventional longwall mining. The device of the present invention consists of a pair of working implements, such as loading buckets, based on Whitworth Quick Return Mechanism. Each segment consists of a powered shaft mounted bull gear having a bevel gear, crank, slider and a pivoted rocker arm capable of providing backward and forward stroke with the help of a link to a ram in a casing which rests on a rack and pinion arrangement. The ram in casing is provided with vertical displacement by a powered shaft mounted cam and follower mechanism. The ram is connected to the working implement, such as loading bucket, through a L-shaped link and guided link. The drive to the powered shaft being given by a prime mover, such as a motor, through a gearbox and pinions. The device is to be mounted on the edges of an Armor Face Conveyor (AFC). The device is useful for loading blasted coal on Armor Face Conveyor (AFC) in minimum possible time and at low cost in conventional panel of longwall mining. Thus enabling enhanced productivity. The schematic diagram of an embodiment of the device of the present invention is shown in figures 1 & 2 of the drawings accompanying this specification. Figures 3 & 4 shows the elevation and plan of the working face in a conventional longwall in an underground coal mine. This invention provides a device useful for collecting and loading post-blast loose coal from conventional longwall face as depicted in per figures 1 and 2. It comprises a pair of working implements, such as loading buckets, based on Whitworth's Quick Return Mechanism. Since both the working implements are mirror image of each other resting on same shaft at two ends, only one implement is explained herein below. Each segment consists of a Bull gear (2) mounted on a powered shaft (21) on which a flat face cam (3) and follower (4) and a pinion (5) are mounted. The Bull gear (2) being provided with a coaxial bevel gear (1) and crank (12) capable of providing adjustable forward and backward stroke as per requirement. The shaft (21) mounted pinion (5) is coupled with a spur gear (6), a gearbox (7) and a prime mover, such as a motor (8) to provide power to the shaft (21). A slider link (9) slides in a slot in a pivoted (11) rocker arm / slotted lever (10) with the help of a driving crank (12) which rotates at uniform angular speed. The connecting link (13) transmits the forward and backward movement through a ram (14), a Lshaped link (16) and a guided link (15) to a working implement, such as loading bucket (17). The ram (14) in a casing (18) is mounted perpendicularly with a flat face follower (4) which reciprocates the casing (18) vertically. The ram (14) in a casing (18) is supported with rack and pinion (19) arrangement at one end. There are four wheels (20) attached at the bottom for rolling at Armor Face Conveyor (AFC) edges along the longwall panel. Accordingly, the present invention provides a device for loading blasted coal from the working face in conventional longwall mining, which comprises a pair of working implements(17), such as loading buckets, based on Whitworth's Quick Return Mechanism, characterised in that each of the said segment consists in combination a Bull gear (2) mounted on a powered shaft (21) on which a flat face cam - follower (3, 4) and a pinion (5) are also mounted, the said Bull gear (2) being provided with a coaxial bevel gear (1) and crank (12) so as to provide adjustable forward and backward stroke through a slider link (9) in a slot in a pivoted (11) rocker arm/slotted lever (10), non-pivoted end of the said rocker arm/slotted lever (10) being connected through a link (13) enabling transmission of the forward and backward movement through a ram (14) in a casing (18), a L-shaped link (16) and a guided link (15) to a working implement, such as the loading bucket (17), the ram (14) in the casing (18) being mounted perpendicularly with the flat face follower (4) enabling vertical reciprocating movement, the said ram (14) in the said casing (18) being supported with a rack and pinion (19) arrangement at the non-working end, the said shaft (21) being powered through the said shaft mounted pinion (5) being coupled with a spur gear (6) of a gearbox (7) connected to a prime mover, such as a motor (8). In an embodiment of the present invention, the Bull gear (2), flat face cam follower (3,4) and pinion (5) are rotatably fixed on the powered shaft (21).In another embodiment of the present invention, the device is provided with a long arm bucket (17). in still another embodiment of the present invention, the forward stroke of the bucket (17) is adjustable as per the distance of the coal face from AFC by adjusting the crank length (12) which rotates about the shaft (21) driven by pinion (5) and spur gear (6) connected to gear box (7) and motor (8). In yet another embodiment of the present invention, the device is provided with wheels (20) attached at the bottom enabling rolling at Armor Face Conveyor (AFC) edges along the longwall panel. The novelty of the device of the present invention for loading blasted coal from the working face in conventional longwall mining, resides in the capability of loading blasted coal on Armor Face Conveyor (AFC) in minimum possible time and at very cheaper cost. In order to minimize the time of forward stroke it should be completed as quickly as possible. This machine is not only less time consuming and economically viable but eco-friendly as well. Hand shoveling will be eliminated to a great extent with the help of long arm bucket attached to the machine. The novelty has been realized by the non-obvious inventive steps of providing in combination a pair of working implements, such as loading buckets, based on Whitworth's Quick Return Mechanism. This has been achieved by employing a crank slotter mechanism coupled to a of bevel gear coaxial to the bull gear, crank which rotates in the shaft. The working of the device of the present invention for gathering blasted loose coal from the working face in conventional longwall in underground coal mines is described below: The operation of the machine is simple. First of all the machine is kept on the rail so designed at the two edges of the AFC. As the motor (8) with gearbox (7) is switched on, the spur gear (6) meshes with the pinion (5), which is, fixed rotatably on the same shaft (21) on which cam (3) and bull gear (2) of the Whiteworth Quick Return Mechanism are mounted. This mechanism works idle in forward stroke and in backward stroke coal is transported through bucket (17) to the AFC. In order to minimize the time of forward stroke it should be completed as quickly as possible. This is achieved by employing a crank slotter mechanism in which bull gear (2), crank (12) which rotates in the shaft (21) and with the help of bevel gear (1). In this way slider (9) has rotating as well as sliding motion and in turn oscillates the rocker arm (10). Considering the rotation of bull gear (2) in anti-clockwise, when slotter lever / rocker arm (10) is in forward stroke, thus pushing the ram (14) forward with the help of connecting link (13) which gives the required motion to the guided link (16) and (15) by stretching / pushing forwarding the bucket upto the coal face. Also during this stroke the cam (3) and follower (4) is in top most position giving a upward vertical displacement to the casing (18) and the bucket (17) with the help of guided link (16), (15) and rack and pinion arrangement (19). In return stroke / backward stroke the rocker arm (10) moves anti clock wise direction. In this stroke connecting link (13) and ram (14) return back, thus with the help of link (16) and guided link (15), bucket (17) comes inward with blasted coal in it. And thus the coal withdrawn through the bucket (17) is poured on to the running AFC for ongoing transportation. During this stroke the cam (3) and follower (4) is in lower position keeps bucket (17) in normal position. The forward stroke of the bucket (17) can be adjusted as per the distance of the coal face from AFC with the help of adjusting the crank length (12) which rotates about the shaft (21) driven by pinion (5) & (6), gear box (7) and motor (8). The main advantages of the device of the present invention for gathering blasted loose coal from the working face in conventional longwall in underground coal mines are: 1. Can be easily transported in underground mines. 2. Simple mechanism. 3. Ease of operation. 4. Reduces labour cost to a large extent. 5. Is an eco-friendly machine. 6. Running cost is low. 7. Maintenance cost is minimal. 8. The cost of the machine is very economical. 9. Saves time per shift in loading the blasted coal and transferring it to the conveyer belt. 10. It is safe. 11. Reduces the revenue investment per ton of coal through higher productivity. We claim: 1. A device for loading blasted coal from the working face in conventional longwall mining, which comprises a pair of working implements(17), such as loading buckets, based on Whitworth's Quick Return Mechanism, characterised in that each of the said segment consists in combination a Bull gear (2) mounted on a powered shaft (21) on which a flat face cam - follower (3, 4) and a pinion (5) are also mounted, the said Bull gear (2) being provided with a coaxial bevel gear (1) and crank (12) so as to provide adjustable forward and backward stroke through a slider link (9) in a slot in a pivoted (11) rocker arm/slotted lever (10), non-pivoted end of the said rocker arm/slotted lever (10) being connected through a link (13) enabling transmission of the forward and backward movement through a ram (14) in a casing (18), a L-shaped link (16) and a guided link (15) to a working implement, such as the loading bucket (17), the ram (14) in the casing (18) being mounted perpendicularly with the flat face follower (4) enabling vertical reciprocating movement, the said ram (14) in the said casing (18) being supported with a rack and pinion (19) arrangement at the non-working end, the said shaft (21) being powered through the said shaft mounted pinion (5) being coupled with a spur gear (6) of a gearbox (7) connected to a prime mover, such as a motor (8). 2. A device as claimed in claim 1, wherein the said Bull gear (2), flat face cam follower (3,4) and pinion (5) are rotatably fixed on the powered shaft (21). 3. A device as claimed in claim 1-2, wherein the said device is provided with a long arm bucket (17). 4. A device as claimed in claim 1-3, wherein the forward stroke of the bucket (17) is adjustable as per the distance of the coal face from Armor Face Conveyor (AFC) by adjusting the crank length (12) which rotates about the shaft (21) driven by pinion (5) and spur gear (6) connected to gear box (7) and motor (8). 5. A device as claimed in claim 1-4, wherein the device is provided with wheels (20) attached at the bottom enabling rolling at armor Face Conveyor (AFC) edges along the longwall panel. 6. A device for loading blasted coal from the working face in conventional longwall mining, substantially as herein described with reference to figs 1 -2 of the drawings accompanying this specification.

Documents:

1101-DEL-2004-Abstract-(07-01-2010).pdf

1101-del-2004-abstract.pdf

1101-DEL-2004-Claims-(07-01-2010).pdf

1101-del-2004-claims.pdf

1101-DEL-2004-Correspondence-Others-(07-01-2010).pdf

1101-del-2004-correspondence-others.pdf

1101-del-2004-correspondence-po.pdf

1101-DEL-2004-Description (Complete)-(07-01-2010).pdf

1101-del-2004-description (complete).pdf

1101-del-2004-drawings.pdf

1101-DEL-2004-Form-1-(07-01-2010).pdf

1101-del-2004-form-1.pdf

1101-del-2004-form-18.pdf

1101-del-2004-form-2.pdf

1101-DEL-2004-Form-3-(07-01-2010).pdf

1101-del-2004-form-3.pdf

1101-del-2004-form-5.pdf