GB1569216A - Mineral mining machines - Google Patents

Description

(54) IMPROVEMENTS IN OR RELATING TO MINERAL MINTING MACHINES (71) We, COAL INDUSTRY (PA TENTS) LIMITED, a company organised in accordance with the laws of Great Britain of Hobart House, Grosvenor Place, London, S.W.1X 7AE England, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed. to be particularly described in and by the follow mg statement: This invention concerns improvements in or relating to mineral mining machines and in particular to such machines for advancing shortwall faces.

One machine of this nature is disclosed in our prior U.K. Patent Specification No. 1 229 238 and includes a conveying track for cut mineral extending transversely to the direction of advance of the machine and disposed adjacent to a floor on which the machine is supported for advance over. a cutter member supported for vertical movement as a whole, the member including a guideway having upper and lower runs extending generally parallel to the conveying track and adapted to support an endless cutter chain, and a drive motor for the cutter chain mounted on the member.

The extraction height of such a machine is dictated by the height of the seam to be excavated and any particular machine is usually designed to cater for a range of heights. In order to enable the machine to cut mineral at various heights, it is necessary to change the disposition or lacing of the cutter picks carried by the cutter chain and possibly to alter other characteristics of the mineral cutting and loading geometry. This is not easily achieved underground in the confined space of the environment in which the machine has to work.

An object of the invention is therefore to provide an improved machine having the facility to operate at various heights without the necessity of having to effect laborious and time consuming alterations thereto.

Accordingly, the invention provides a mineral mining machine including a conveying track for cut mineral extending transversely to the direction of advance of the machine and disposed adjacent to a floor over and on which the machine is supported for advance, a cutter member supported for vertical movement as a whole, the member including a guideway having upper and lower runs extending generally parallel to the conveying track and adapted to support an endless cutter chain. a drive motor for the cutter chain mounted on the member, and means for continuously ranging the cutter member in use.

Preferably adjustment means are provided for varying the amplitude of the ranging movement of the cutter member.

The means for continuously ranging the cutter member may include a crank mechanism driven by a motor, the mechanism being adapted to oscillate the cutter member.

Alternatively the means for continuously ranging the cutter member may include fluid-operable rams sequenced to give an oscillatory movement to the member.

The cutter member may conveniently be mounted on a pivot arrangement.

By way of example only two embodiments of mineral mining machine according to the invention are described below with reference to the accompanying drawings in which: Figure 1 is a schematic view of a first embodiment: Figure 2 is a circuit diagram for a fluid control circuit applicable to a second embodiment.

Referring to Figure 1. there is shown a mineral mining machine 1 disposed adjacent a shortwall face, e.g. a heading, indicated at 2. The machine 1 includes a conveying track 4 consisting at least in part of a ramp plate 6 which forms a portion of base 8 having upstanding therefrom at least two pivot mountings 10, only one of which is shown, one being located at or towards each end of the machine 1.

Two support arms 12. only one of which is shown, support a rigid cutter member 14 comprising a guideway 16 having upper and lower runs 18, 20 respectively, the arms 12 being pivotted to the mountings 10. A cutter carrying chain diagrammatically shown at 22, is slidable around the guideway 16 and carries a plurality of cutter picks 24 disposed at spaced intervals along its length and loading paddles 26.

The machine 1 is provided with a drive shaft 30 carrying two cranks 32, 34 to each of which is pivotally attached a connecting rod 36. Each rod 36 is connected to the one support arm 12 through the agency of a pin 38 the position of which on the arm may be varied. A drive motor 40 is coupled to the shaft 30 and is fluid operable with a variable speed facility.

In use, the chain 22 is driven by a motor (not shown) thereby to cause the cutter picks 24 and paddles 26 to move. At the same time, the drive motor 40 is actuated to rotate the shaft 30 and to move the cranks 32, 34 which cause the rods 36 to swing about the little end 42 of the cranks 32, 34.

In so doing the arms 12 are reciprocated about the mountings 10. This ranging motion of the arms 12 and thus the guideway 16 is maintained throughout the cutting operation and the amplitude of the oscillation determines the full extraction height of the machine depending on the setting position of the pin 38. A variation in this setting position will effect a change in extraction height. The first embodiment thus provides a simpler means of varying extraction height than the methods used hitherto.

Referring now to Figure 2. the hvdraulic circuit 50 there depicted is intended as a control for two lift rams 52 attached between the base 8 of the machine 1 and the arms 12 thereof, although these features are not shown in Figure 2. the rams replacing the drive shaft and crank arrangement of Figure 1.

The circuit 50 includes a sequence reversing valve 54 connected to a pressure line 56 and a return line 58 to tank 59 at the input and exhaust ports 60. 62 respectively. Two outlet ports 64, 66 are provided on the valve 54 and are coupled through lines 68, 70 each of which includes a restrictor and non-return valve assembly 72. Line 68 is teed into a supplv line 74 connected to the full bore sides of both lift rams 52 and line 70 is teed into a supply 76 feeding the annulus side of the rams 52. A line 80 is teed into line 74 and feeds into a pilot-operated change over valve 82. a pilot feed line 84 being tapped into line 80 and communicating with the control end 86 of the spring-biased spool of valve 82 as shown.The valve 82 is connected via line 88 to one end of sequence reversing valve 54 as indicated, and has another port 90 connected to tank 59.

A line 100 is connected into line 76 and leads to a pilot operated change-over 102, similar to valve 82, which has a control end 104 to which a pilot feed line 106 is connected, the line 106 being tapped into line 100. The valve 102 has a pilot line connection 108 to the other end of sequence reversing valve 54 as indicated, and has another port 110 connected to tank 59.

The operation of the hydraulic circuit is as follows. Pressure fluid is fed via line 56 to valve 54 which, in the position shown in Figure 2, allows flow of fluid into line 68 whence it passes into line 74 and to the full bore side of rams 52 to extend. Once they have reached their maximum extension, a back pressure is generated in line 80 and hence pilot line 84. This back pressure acts on the control end 86 of valve 82 to cause its spool (not shown) to move against the action of the spring 120. This movement connects line 80 to line 88 and the pressure fluid flows therethrough to act on the left-hand end (as viewed in the Figure) of valve 54. In so doing the pressure fluid causes the valve spool (not shown) of valve 54 to move to the right displacing fluid in line 108 through valve 102 to tank 59.The effect of this is to connect the pressure line 56 to the line 70 and to connect line 68 to the return line 58 and to tank 59. The annulus side of the rams 52 is now pressurised whilst the full bore side is connected to exhaust.

The pressure is thus relieved in line 80 and the valve spool of valve 82 may return under the action of spring 120.

The retraction of rams 52 can now take place and once this is complete. a back pressure will build up in line 100 and through line 106 on end 104 of valve 102, the spool (not shown) thereof is displaced against spring 130. This connects line 100 to line 108 and thus to the other end of valve 54 to reverse the connections of pressure feed line 56 and return line 56 to lines 68, 70 respectively. The extension of the rams 52 can then recommence.

It can be seen therefore that a continuous oscillating movement is given to rams 52 thus causing the cutter member of the machine 1 to range continuously up and down whilst the machine is cutting and advancing into the shortwall face. As with the first embodiment. the second provides a facilitv wherebv the machine of the invention is capable of providing a range of extraction heights without the necessitv of laboriously changing the cutter pick lacing pattern or fixing in adaptor sections to cater for change in seam height. The stroke of the rams is 52 conveniently variable and can thus cater for such a change in seam height quite readily.

WHAT WE CLAIM IS: 1. A mineral mining machine including a conveying track for cut mineral extending transversely to the direction of advance of the machine and disposed adjacent to a floor over and on which the machine is supported for advance, a cutter member supported for vertical movement as a whole, the member including a guideway having upper and lower runs extending generally parallel to the conveying track and adapted to support an endless cutter chain, a drive motor for the cutter chain mounted on the member, and means for continuously ranging the cutter member in use.

2. A machine according to claim 1 in which adjustment means are provided for varying the amplitude of the ranging movement of the cutter member.

3. A machine according to claim 1 or 2 in which the means for continuously ranging the cutter member includes a crank mechanism driven by a motor, the mechanism being adapted to oscillate the cutter member.

4. A machine according to claim 1 or 2 in which the means for continuously ranging the cutter member includes fluid operable rams sequenced to give an oscillatory movement to the cutter member.

5. A machine according to any one of the preceding claims in which the cutter member is pivotally mounted.

6. A mineral mining machine substantially as hereinbefore described with reference to Figure 1 or 2 of the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (6)

**WARNING** start of CLMS field may overlap end of DESC **. rams is 52 conveniently variable and can thus cater for such a change in seam height quite readily. WHAT WE CLAIM IS:

1. A mineral mining machine including a conveying track for cut mineral extending transversely to the direction of advance of the machine and disposed adjacent to a floor over and on which the machine is supported for advance, a cutter member supported for vertical movement as a whole, the member including a guideway having upper and lower runs extending generally parallel to the conveying track and adapted to support an endless cutter chain, a drive motor for the cutter chain mounted on the member, and means for continuously ranging the cutter member in use.

2. A machine according to claim 1 in which adjustment means are provided for varying the amplitude of the ranging movement of the cutter member.

3. A machine according to claim 1 or 2 in which the means for continuously ranging the cutter member includes a crank mechanism driven by a motor, the mechanism being adapted to oscillate the cutter member.

4. A machine according to claim 1 or 2 in which the means for continuously ranging the cutter member includes fluid operable rams sequenced to give an oscillatory movement to the cutter member.

5. A machine according to any one of the preceding claims in which the cutter member is pivotally mounted.

6. A mineral mining machine substantially as hereinbefore described with reference to Figure 1 or 2 of the accompanying drawings.