Abstract: A water spray nozzle (1) for location in a receiving bore (2) of a pick box (3) of a rotary cutting head (4) of a mining machine, comprising an elongate and generally cylindrical body member (5) having at one end an entry nose (6) and at the other end an enlarged extraction head (7), in use, intended to remain outside the receiving bore (2). A radial, water inlet orifice (8) intermediate the ends of the body member (5) leading to a water receiving chamber (25). A water sealing ring (9) located in a retaining groove (10) in the body member (5) between the water inlet orifice (8) and the nose (6) . A water discharge orifice (11) is in communication with the chamber (25). A reduced diameter formation (12) on the body member (5) has a resilient, nozzle-retaining ring (13) of material and/or dimensions such that it is compressible and/or deformable, into a nozzle retaining mode, without additional retaining means.

Abstract: A water spray unit is provided, to be located in a receiving bore provided in a pick box. The unit comprises an elongate nozzle portion and a fastener for the nozzle portion. The nozzle portion has an internal water receiving chamber and a water inlet orifice communicates with the chamber. At one end of the nozzle portion, a water discharge orifice communicates with the chamber. An external screw thread is provided on the fastener and drive surfaces on the fastener serve to screw or unscrew the fastener. One end of the nozzle portion is distal from said fastener and terminates in a nose having a frustoconical sealing surface, adapted, in use, to be forced by the fastener, into tight, water sealing engagement with a complementary frustoconical seat of the receiving bore. The invention also includes a pick box provided with such a water spray and a rotary cutting head provided with such a pick box.

Abstract: A gearbox for a rotary, mineral cutting head, comprises a casing housing speed reduction gearing and also a portion of a drive shaft supported by first and second, spaced-apart bearings, with at least one radially extending cylinder having a closed inner end and an open, outer end provided in said drive shaft and a reciprocable piston partially housed in said cylinder with a fluid seal between said piston and said cylinder; a variable volume, pressure-generating chamber defined between a radially inner end of said piston and a closed, inner end of its cylinder; a ring surrounding said drive shaft and having an inner profile and with a radially outer end of said piston in contact with said inner profile and with said piston.

Abstract: A mineral cutter tip 14 comprises a bottom face 15 and a rear face 16 located in "V"-formation whereby the tip 14 is, in use, seated in a "V"-notch 7 provided in a head 2 of a mineral cutter pick 1, the tip 14 further comprising a front cutting face 17 and, reawardly thereof, a water-conveying slit or slot 20 provided intermediate opposed, lateral side faces 19 of the tip 14, and having a water inlet end 23 emerging at the rear face 16 of the tip 14 and a water outlet end 24 emerging at the top face 18 of the tip 14. The invention also includes a pick 1 provided with a tip 14 as defined.

Abstract: A roadheader type mining machine (1) comprises a self-propelled chassis (6), an elongate boom (9) having a longitudinal axis (10), rotary cutting head (15) having a plurality of water spray nozzles (17). The boom (9) is of a two-part construction comprising an inner part (18) that is non-rotatable about the boom longitudinal axis (10), that is supported from one end (8) on the chassis (6), and that carries towards its other end (14) bearing means (19) for rotatably supporting an outer part (20) that axially extends from said inner part (18).

Abstract: A mineral cutting device comprises a plurality of replaceable picks (10, 10A-10G) and associated water conveying lances (20, 20A-20G), each lance being of flexible, tubular synthetic plastics material having a hollow, water-conveying interior and being contained, at least partially, within a bore (13, 13A, 13B) in the pick (10, 10A-10G) when the pick (10, 10A-10G) has been mounted on the device (1, 1A, 1B), to line the bore and prevent water pressure within the lance being effective on the pick, with a terminal end of each lance provided with a metallic nozzle secured in water sealing manner thereto and providing a water discharge orifice (23). The invention further includes a lance (20, 20A-20G) for use with the mineral cutting device defined above, and also a shank bore (13B) formed at least partially in a side (27) of the pick shank (12, 12A-12D), which, in use, is the compressive stress side, and/or with an inner bore end (15) intersected by a slot (42) provided in at least a portion of the shank (12D).

Abstract: A rotary mineral winning/rock cutting head 1 comprises a plurality of water discharge nozzles 8, at least one supply conduit 23, 24, 25, 26, 28, 30, 35, 36, 37 to convey, in use, pressurized water to the discharge nozzles 8 from a supply source, and valve means 38 associated with the or each conduit 23, 24 to permit or prevent a flow of water along the conduit(s) 23, 24, to achieve phased water control with water discharge from the nozzles 8 located in, or adjacent, the cut segment in the course of rotation of the head 1, and no discharge from the nozzles 8 located in, or adjacent, the non-cut segment, each valve means 38 comprising a rotary valve member 43, with an actuator shaft 45 operable on the valve member 43 to rotate the latter through "on" and "off" positions, and at least one arm 50 extending radially from the actuator shaft 45 and adapted, upon rotation of the head 1, to be displaced by contact with, and/or guidance by, an abutment device 53 to cause rotation of the arm 50, and hence both its actua

Abstract: A haulage system for a mining machine comprises a mining machine mounted on and/or guided by a conveyor and reciprocable with respect thereto, the conveyor being provided with a rack having plural rows of teeth of identical pitch, with the teeth of one row staggered with respect to an adjacent row(s), and the machine being provided with at least one power driven haulage sprocket comprising plural sets of peripherally arranged teeth of identical pitch, one set being angularly staggered with respect to an adjacent set(s), whereby one set is engageable with each row of teeth of the rack. The invention also includes a mining machine provided with such a power driven haulage sprocket, and a rack as above described and provided with end fittings for securing in articulated manner to an adjacent rack.

Abstract: An "in-web" mineral winning machine 1 for reciprocation along a mineral face, comprises an elongate machine body 2, adapted, in use, to be located beyond the face side sidewall 14 of an armoured conveyor 16 extending along the mineral face, at least one bridge 10 extending rearwardly from the machine body 2 and adapted, in use, to overlie the conveyor 16 and to engage slidingly a trapping means 19, 20, 21 located at the goaf side 15 of the conveyor 16, the or each bridge 10 housing a machine haulage unit 34, and the or each bridge 10 being connected to the machine body 2 by at least one joint 9 providing for articulation along an axis 11 extending parallel to the longitudinal axis of the machine body 2.

Abstract: An end cutting unit for a mining machine comprises a cutting unit body, a ranging arm carrying a drivable cutting device, said ranging arm being carried by the cutting unit body at a location towards a first end thereof, and a transmission for transmitting drive to the cutting device. In order that the end cutting unit may be adaptable to advance and retreat mining uses as required, transmission is provided with two drive couplings respectively at said first end and at the opposite second end of the cutting unit body to enable rotary drive to be transmitted to the cutting device from a selected one of said drive couplings, and the ranging arm is capable of being set in a position, about which the arm can be ranged, in which the arm extends generally away from the end of the cutting unit body at which is located whichever drive coupling has been selected to impart rotary drive to the cutting device.

Abstract: A mineral lump breaker, for example for use in conjunction with a coal conveyor in a mine, comprises a breaker element and reaction means, for example in the form of a breaker plate or reaction discs. The breaker element and reaction means are carried by a framework straddling the conveyor and are spaced-apart so as to define between them a lump breaking gap. Material on the conveyor is moved into the gap where it is impacted by the breaker element against the reaction means. The reaction means is adjustable with respect to the breaker element periphery to vary the gap dimension.

Abstract: A longwall mining machine incorporates breaking apparatus comprising an underframe which may be an integral extension of the main underframe of the machine and which is mounted on the conveyor for movement therealong, such that the breaking apparatus is rigidly secured to, and comprises an integral part of, the mining machine. The breaking apparatus also comprises a rotary breaking element drivably carried by the breaker underframe and a reaction plate, for example, on the same underframe, which is spaced from an adjacent periphery of the breaking element. In use, material, such as coal and rocks, on the conveyor passing between the rotary element and the reaction plate is broken against the reaction plate by the rotating breaking element. In this way, the coal and rocks are broken down to a sufficiently small size that they will not become jammed under the main underframe of the mining machine.

Abstract: Breaking apparatus for use with a conveyor and intended to be used in a coal mine comprises a frame generally of inverted U-shape bridging the conveyor and secured to its opposite side walls. A rotary breaking element is drivably carried on an arm assembly mounted on the frame, and a reaction plate on the frame is spaced from an adjacent periphery of the rotary element. In use, coal and rocks on the conveyor pass between the rotary element and reaction plate where they are broken up by the rotary element as it rotates.

Abstract: An auxiliary device for a longwall mining machine incorporating an underframe, by which it is mounted for movement along the conveyor of the mining machine, and it is coupled to the mining machine. The auxiliary device comprises a rotary breaking or crushing element drivably carried by the underframe and the underframe is provided with a reaction means, preferably a plate, spaced away from an adjacent periphery of the rotary element. In use, material on the moving conveyor passes between the rotating breaking or crushing element and the reaction plate where the material is broken up or crushed. In this way, it can be ensured that any large lumps of coal or rock on the conveyor can be broken down to a sufficiently small size so as not to become jammed beneath the main frame of the mining machine straddling the conveyor.