Abstract: The invention relates to ranging drum shearers having cutting drums driven by electric motors mounted on the respective ranging arms. A coal sizer is pivotably mounted on a shroud of the motor and is maintained at a constant disposition regardless of the position of the ranging arm. The coal sizer is maintained at a constant disposition through a control arm pivotally mounted to the pivot axis of the ranging arm and having a keyway containing a key on the axis of the coal sizer. The key and keyway provide for longitudinal movement of the coal sizer relative to the shearer body whereby on the pivotal movement of the ranging arm, the control arm remains stationary and the distance between the key and the axis of the shroud is maintained by the longitudinal adjustment of the coal sizer in the keyway.

Abstract: A combination of a cutting tool (10) and a holder (14) defining a socket (13) for receiving a shank (12) of the cutting tool, wherein the shank includes a slot (17) extending transversely to its longitudinal axis, an elongate locking bar (20) mounted in the slot and projecting therefrom, and resilient means (19) biassing the bar into its projecting position and wherein the holder includes an elongate abutment member 21 releasably connected thereto and co-operable with the locking bar to retain the shank within the socket.

Abstract: The inspection line pan has an opening (11), in its deck plate (10) and a three-piece door (12) located in the opening. The door is formed of three rectangular panels (15, 16, 17) of similar length and width which are disposed transversely of each other. The outer panels (15, 17) are pivotally connected to the center panel (16) and the center panel has transverse grooves (18) which are supported on tongues on central portions of the opening (10) for transverse movement. In use, one or other outer panel can be pivotally raised for inspection below the line pan. If access to the area below the line pan is required, the center panel can be slid transversely into the space created by the raised outer panel and after the center panel is free of the tongues, it can be lifted clear of the opening. If the outer panels are attached to the center panel, they are lifted clear of the opening with the center panel; otherwise they are removed separately.

Abstract: Apparatus for manipulating a tool which is particularly suited for use in drilling and inserting bolts into thin seams of mine workings. The apparatus (100) comprises a reaction support member (4) to support the tool, a chuck (1) for holding the tool, mounting member (12) in which the chuck (1) is mounted, and a lever linkage (13) connected between the mounting member (12) and the support member (4). The lever linkage (13) comprises parallel chuck orienting members (5, 10) connecting the mounting member to a control member (9), said control member being adapted to manipulate the chuck orienting members and to control the orientation of the chuck. The lever linkage further comprises first and second links (14, 15) each having first and second ends. The links are pivotally attached to each other at the first ends thereof. The first link is pivotally attached at the second end thereof to the mounting member and the second link is pivotally attached at the second end thereof to the support member.

Abstract: An angle station for an endless conveyor belt has an upper and a lower horizontal roller bank disposed in parallel with each other across a framework across the angle station. The angle of entry to the angle station of the upper run is co-linear with the exit of the lower return run. A reversing roller is associated with the lower bank to reverse the direction of the incoming return run before it passes over and around the lower roller bank and a reversing roller is associated with the upper bank to reverse the direction of the outgoing upper run of the belt after it has passed over and around the upper roller bank. The roller banks are interchangeably mountable on the framework to receive a right-handed or left-handed belt.

Abstract: A flexible track (10) is held captive in an armoured face conveyor and comprises a plurality of blocks (14) arranged in longitudinally spaced relation with a pair of links (15) at opposed transverse sides of each adjacent two blocks interconnecting said blocks and forming apertures (18) between adjacent blocks. The blocks (14) have side projections (16) and the links (15) have corresponding apertures which are of slightly greater dimensions longitudinally to permit a small amount of longitudinal movement (end-float) of each block (14) relative to its two pairs of links (15). Each block has a vertical aperture (22) through its body, the apertures (22, 18) in the blocks and between the end faces (20, 21) of adjacent blocks being adapted to receive a tooth (25) of a toothed wheel (26) mounted on a machine movable along the conveyor.

Abstract: A circular heading machine for excavating tunnels by advancing a machine in stepwise fashion and erecting tunnel supports, having an elongate machine body at the forward end on which a forwardly directed cutter boom is mounted. Rams advance the machine body in stepwise fashion acting against grippers and a profile ring limits peripheral movement of the cutter boom to form an accurate profile. A gathering apron is provided at the forward extremity of the machine body. The cutter boom is mounted on a sliding carriage longitudinally movable on and independently of the machine body and a hood overlies the apron. A cage structure extends rearwardly from the hood structure and surrounds the body cutter and sliding carriage and tunnel support erecting members are provided externally of the cage structure, directly behind the hood structure. The hood is a semi-circular member supported by hydraulic rams for height adjustment.

Abstract: In an angle station for an endless conveyor belt, there are presented to each incoming run of the belt stationary curved guide members (18, 19) of the shape of a major segment of a right-circular cylinder and having in the part-cylindrical portion (16 or 17) thereof rectangular openings (15) arranged in parallel and helical paths and through which project small freely-rotatable rollers (14), the continuously-changing segments of the curved surfaces of which projecting through said openings (15) are in attitude to change the direction of travel of the belt (13) through 90.degree. during passage of the belt about the part-cylindrical portion (16 or 17) of the guide member (18 or 19).

Abstract: A line pan for an AFC conveyor including a pair of sigma-section sides parallel and transversely spaced, a deck plate between the sides, and a base plate to which the sides are attached. The upper part of each sigma-section side and the deck plate are removably attached to the lower parts of the sigma-section sides and the base plate, and the deck plate has a transversely slidable section which can slide out of the deck plate for inspection of the conveyor components below the deck plate.

Abstract: The drive gearbox comprises an in-line primary box, a right-angled primary box and a nose module which can be coupled to one or both primary boxes. Each primary box has an open-ended interface which exposes gearing and the nose module has two open interfaces which expose gearing when the primary boxes are coupled to the nose modules, the gearings mesh with the gearing.If only one primary box is coupled to the nose module, a cover (not shown) is placed over the open interface.A gearbox formed of nose module and one or both primary boxes are advantageous in several ways, such as adaptability, power capacity, shape and size and design.

Abstract: A link component is adapted for interfitment with like link components to form a flexible chain free of hinge pins and cooperable with a drive sprocket. The link component has complementarily-shaped end parts (10, 11; 10' 11') whereof each is the true or inverted image of the other. Each end part comprises a transverse recess (20) located between transverse walls (21, 22) of which the longitudinally outer wall (22) is shorter than the inner wall (21). The shorter end of the outer wall (22) and the recess (20) have complementary rounded formations so that when the end part of one link (10 or 10') interengages with the end part (11 or 11') of an adjacent link, the respective outer walls (22) locate in the corresponding recess (20). Parallel side braces (12, 12') space the end parts (10, 11; 10' 11') apart through integration therewith and have external surfaces spaced laterally beyond the width of the end parts.

Abstract: A control system for eddy current coupling drive for armoured face conveyors wherein the systems controls a number of eddy current drives via a pair of power supply lines and a single pilot line. A main contactor controlled by a relay is held closed by contact of a pilot relay which is energized only if relay contacts in individual control units for each drive remain closed. These last mentioned contacts open if certain operating conditions are not met.

Abstract: A longwall coal-mining machine has a gearcase at each of its ends, each gearcase carrying two ranging arms respectively mounting a cutter drum and a lump breaker, and also carrying a haulage drive. Each gearcase comprises a casing having therein first and second co-axial and mutually-spaced transverse horizontal shafts projecting through opposite sides of the casing driven by individual transmissions located in the gearcase and from an electric motor and a hydraulic motor, respectively, both outside the casing. Rotation of the second shaft drives the mining machine along a longwall face. Rotation of the first shaft actuates a cutter drum through a gear train and also actuates a lump breaker through a gear transmission.