Abstract: A mine roof support having means for monitoring the angles made by the canopy 11 and the base 10 with respect to a datum. The angular information may be gathered in a number of different ways and the information used to control subsequent movements of the support.

Abstract: Mining apparatus comprises two rigid elongate members joined together in an articulated manner and a signalling device arranged to provide information dependent upon the relationship of one of the members with respect to the other of the members. The invention is particularly applicable to measure the relationship between adjacent pans and an articulated mine conveyor, for example to assist in the alignment of the conveyor. The signalling device may have two base members which, in use are respectively bolted to two adjacent pans of an articulated conveyor. Relative movement between the members is translated by components into movement detectable by rectilinear potentiometers.

Abstract: Mine roof support comprising a base including a pair of skids, a roof engaging canopy, jacks acting between the base and the canopy, an auxiliary jack connected to the base for lifting or lowering at least part of the base when the support advances and a lost motion arrangement connected between the base and the auxiliary jack for aiding movement of the base and the roof engaging canopy toward each other. The lost motion arrangement is connected to each of the skids by a pivotal connection which permits the front end of one skid to move vertically to a limited extent with respect to the front end of the adjacent skid.

Abstract: Apparatus for transmitting data relating to a mining machine in a longwall mining operation, comprising a data collection device mountable on a mining machine for collecting data relating to the machine, a data transmission device also mountable on the mining machine for transmitting the data in the form of a remote signal, and a plurality of receiving devices each mountable on one of a plurality of mine roof supports past which the machine is arranged to travel. The apparatus also includes a data conveying device for conveying the data away from the mine roof supports.

Abstract: A drive frame (1) for a scraper chain conveyor comprises a pair of spaced-apart parallel sidewalls (2), interconnected by a cross-member (3) welded to both sidewalls (2); a sprocket barrel assembly (18) provided with at least one sprocket ring (19) adapted to engage at least one endless chain assembly of the conveyor; mutually engageable seating surfaces (23, 5) provided respectively on the sprocket barrel assembly (18) and on the cross-member (3); at least one abutment face (7) provided on the cross-member (3); at least one abutment face (26) provided on the sprocket barrel assembly (18) in close but spaced proximity from the cross-member abutment face (7) to define at least one upwardly open pocket (27); and a releasable fastener (28) for securing the sprocket barrel assembly (18) to the drive frame (1) via the seating surfaces (5, 23) that is lowerable into, and raisable from, the pocket (27), and that is also actuable and accessible from above.

Abstract: An hydraulic power generating pack 1 comprises a primary pump 23 of the multi-cylinder, reciprocating ram type with a reciprocable piston 27 located in each cylinder 28 and displaceable by a crank shaft 20 rotatable by a prime mover 2 to provide a primary hydraulic fluid output 32 at a predetermined constant pressure and constant volume, and a power take off 14 to drive a secondary pump 36 of the pressure compensated variable delivery type, the output 40 of which drives a pressure intensifier 42 serving to intensify, to the required secondary pressure and volume, hydraulic fluid supplied to the intensifier 42 at a first pressure and volume.

Abstract: A valve assembly is provided for use in controlling a plurality of fluid operated functions. The assembly comprises a plurality of valve members 14, each movable independently to carry out a fluid flow control function for example, a function of a hydraulic mine roof support. There are means 39 for supplying hydraulic fluid to all the valve members 14 thus tending to move all the valve members, but there is also an interposer device 18 positionable in the path of at least one of the valve members to prevent the said one of the valve members from carrying out its fluid control function, thus enabling the valve members to be selectively operable.

Abstract: A mine roof support has a roof engaging canopy 23, a floor engaging base 12, and a hydraulic jack 24 acting between the canopy and the base for urging the canopy and the base apart. The hydraulic jack 24 is provided with at least two different locations, movement of the jack means 24 from one location to another location bringing about an alteration in the distance between the canopy and the base. The invention makes it possible to provide a hydraulic jack having a first working position in which the hydraulic jack is arranged in the optimum position to support a mine roof, and a second stowing position for transportation purposes.

Abstract: A self-advancing mine roof support comprising a floor engaging base 11, a roof engaging canopy 12, hydraulic jacks 19a, 19b to urge the base and canopy apart, and a linkage system located towards the rear of the support. The linkage system comprises an inclined shield member 22 pivotally connected to the canopy 12, and at least two links 23, 24 interconnecting the shield and the base. The jacks 19a, 19b, are located substantially halfway along the length of the base and extend substantially vertically from the base. There is a hydraulic jack 18 operable between the roof engaging canopy 12 and the linkage system to effectively counterbalance the projection on the canopy 12 which extends forwardly of the jacks 19a, 19b.

Abstract: A roof engaging structure for a mine roof support comprises at least two relatively movable roof engaging members 21 and 23, which are coupled together by at least two spaced-apart pivotal joints 25 and 26. The pivotal joints combine to influence the relationship of the roof engaging surfaces of the two members. In one embodiment for example, the roof engaging surfaces of the two roof engaging members may adopt either an angular or a parallel relationship with respect to one another, one surface lying at least partially below the adjacent surface. The arrangement enables the roof engaging structure to shape itself to various forms of mine roof, while preventing jack knifing of the forward end of the roof engaging structure.

Abstract: A mining machine having a mineral winning head mount including a plurality of links pivotted successively one to another and powered means for pivotting the successive links about their pivot axes and whereon said links and powered means allow the mineral winning head to be retracted at least partially into an angled configuration of the links.

Abstract: A mine roof support control monitoring system in which at least some of a row of self advancing mine-roof supports at a mine face each include means for providing data relating to successive advances of that support. This data is accumulated by other means of the system and stored to give readily available indicationsof differences of actual support advances. The system preferably further includes means for pre-energizing the advance mechanisms of such supports to eliminate data relating to slack or tolerance.

Abstract: The invention is concerned with mine-roof supports, especially self-advancing mine-roof supports and provides a support comprising a base, a shield inclined downwardly and rearwardly towards the rear of the base and pivotally attached to said base, a roof-engaging canopy pivotally attached to an upper part of the shield, hydraulically; extensible prop means operatively positioned between the base and said shield, and hydraulically-extensible prop means operatively positioned between the base and the canopy. In some preferred embodiments of the invention the shield is a completely non-roof-engaging member and the pivotal connection between the shield and the baseis such that raising and lowering of the shield, by the prop means between said shield and the base, does not involve material angular displacement of said prop means. The pivotal connection between the canopy and the shield conveniently includes a debris excluding joint between said canopy and shield.

Abstract: A roof-engaging assembly for a mine roof support having prop or jack means to engage and support the roof-engaging assembly, comprises a rigid part to engage said prop or jack means, and a roof-engaging part positioned over and resiliently urged away from the rigid part. Preferably the rigid part has a roof-engaging face and a relatively stepped or recessed face below the roof-engaging face, the roof-engaging part being positioned over and resiliently urged away from the stepped or recessed face and towards positions above the roof-engaging face of the rigid part.

Abstract: A control system for a self-advancing mine roof support includes function selection hydraulic valve means responsive to coded electrical signals from remote means for selecting a desired function, and means for comparing the coded signals with other signals representing the instantaneous function state of the valve means. Usually each of a plurality of supports incorporates the remote means of a neighboring support.

Abstract: The invention is concerned with a self-advancing mine roof support comprising a base, hydraulically extensible prop means mounted on said base and a roof-engaging structure, including a canopy, mounted on said prop means for application thereby to a roof to be supported. On at least one side of the roof support there is a laterally extensible and retractable auxiliary canopy and a device is provided for urging and extending said auxiliary canopy laterally outwardly with respect to the support. The auxiliary canopy on the support bears firmly against a similar auxiliary canopy on an abutment on a neighboring roof support so as to prevent roof material falling between the two supports. Because it is retractable, however, the auxiliary canopy does not interfere with the advance of the supports. Conveniently the auxiliary canopy comprises two box-like members fitted telescopically one within the other.

Abstract: A mine roof support of the type having a canopy supported from a base structure by hydraulically extensible legs and a cantilever roof-engaging member pivotally attached to the forward end of the canopy, is provided with a selectively positionable laterally extending cantilever member by means of which the effective roof-engaging surface of the canopy can be extended, the lateral cantilever member being optionally provided with a forwardly projecting cantilever member by means of which the effective width of the roof-engaging member can also be extended.

Abstract: A control means, for a mine roof support having hydraulically extensible prop means and some other pressure-fluid-operated component (e.g. a hydraulic ram for advancing the support), comprises a control valve having selectable positions in one of which (the prop extend position) it will select for a supply of hydraulic pressure-fluid to said prop means. The control means also include a valve device having a position in which it will provide for a supply of pressure-fluid to the prop means and having means adapted to cause it to move to that position, when the control valve is operated to the prop extend position, and to keep it in that position even position. the control valve is operated from the prop extend positon. By this arrangement a pressure-fluid supply to the prop means will still be maintained so as to ensure proper setting thereof and to make up any leakage of fluid.

Abstract: A self-advancing mine roof support of which the ground-engaging structure comprises a pair of spaced apart skids in the spacing between which the relay bar structure of the advancing mechanism is housed, such structure being powered by a pair of pressure-fluid operated rams disposed one adjacent each of said two skids.