Abstract: A cutting head for a selective cutting machine includes internally-fed spraying means including a high pressure water control means which is designed in such a way that only spray nozzles adjacent to cutting tools that are actually cutting are supplied with water under pressure. The water under pressure is supplied from a boom to the rotating cutting head via a piston whose free end surface is pressed, by the pressurized water, against a control surface provided on the cutting head. Said free end surface is formed with a control opening which overlaps control ducts provided in the control surface during rotation of the cutting head, thereby controlling the flow of pressurized water to the various groups of spray nozzles. Non-return valves, which keep the control ducts closed, when they are not aligned with the control opening of the piston, are located in the control ducts.

Abstract: To facilitate the fixing of attachments to the side walls of scraper-chain conveyors upstanding recesses are provided in the side walls in upper regions where the upper flanges merge with the side walls. The recesses, which can be milled, open from the upper flanges and have a depth less than the thickness of the side wall upper regions. The recesses are generally U-shaped as viewed from the exterior. The recesses are enlarged or undercut internally to be deeper all round so as to provide shaped pockets which exactly match the shape of non-circular heads of threaded elements which are received therein and fill the recesses.

Abstract: A distributor block for interconnecting a hose bundle to a control device of a pressure fluid control system in an underground mine working has internal passageways for connecting valves of the device to individual hoses. Bores in the block receive detachable elongate coupling members which themselves have internal bores and plugs for engaging in sockets within the control device. The coupling members are journalled in the block for slight transverse and angular movements within seals.

Abstract: A cross-axis cutting assembly of a selective cutting machine is provided with internally-fed spray means. The assembly includes two cutting heads supported by a boom, the cutting heads being driven by a shaft which is transverse to the boom. A high pressure water supply line for each cutting head is provided by means of a connecting member. Each connecting member is arranged externally on the boom, is preferably designed as a channelled plate, and closely fits the external contour of the associated cutting head. Each connecting member extends to the free end of the shaft, and is connected to an internal high pressure water duct formed in the associated cutting head by means of a rotary arrangement. Each rotary arrangement has an axial pin which fits sealingly into a passage.

Abstract: A pressure-relief hydraulic valve device for mining equipment is composed of a hollow sleeve mounting a guide with a through bore slidably receiving the stem of a valve member. The stem is provided with a blind axial bore leading to a set of radial bores and a seal in the bore of the guide co-operates with the radial bores to form a valve. A spring accommodated in the sleeve acts through a shaped pressure member to urge the valve member to a position with the valve closed. Pressure fluid in equipment to be protected acts on the valve member and excess pressure displaces the valve member against the spring force to open the valve and permit the escape of fluid via an outflow chamber and outlets in the sleeve. The pressure member has a piston like flange guided within the sleeve against which the spring bears and the underside of the flange of the pressure member is shaped to provide a concave guide face in the outflow chamber.

Abstract: A mineral mining installation employs a scraper-chain conveyor constructed from individual pans joined end-to-end and a plough having a drive plate running beneath the conveyor and on a skid bed formed as a sub-frame structure on the floor of the working. The drive plate is connected via guide means to the haulage run of a chain in a lower guide passage at the side of the conveyor opposite to the plough. An upper guide passage accommodates the return run of the chain. The passages are defined by a guide structure fitted to the side walls of the pans and includes detachable covers which can be removed for access purposes. At least some of the covers are linked with the sub-frame structure with the aid of tongue-and-groove connections.

Abstract: A loading apparatus comprises a ramp defining a loading surface and a pair of loading blades each having a triangular cross-section with a nearly perpendicular front face and a shallow inclined rear face relative to a desired delivery direction for material collecting on the loading surface. The blades are oscillated back and forth about upstanding pivot axes relative to the loading surface. Between the blades is a component or some other means defining a step with a similar configuration to the blades with a steep front face relative to the delivery direction and a shallow inclined rear face. The step defining means assists the blades in the loading work.

Abstract: As is known mineral, e.g. coal, is won from a mineral face with the aid of a winning machine guided for movement along a conveyor composed of individual pans joined end-to-end. The conveyor is advanced towards the face behind the machine by shifting rams linked to the pans. In accordance with the invention, the rams are connected to and disconnected from a supply of pressure fluid in a controlled manner to form a group composed of a predetermined number of rams which are simultaneously charged with pressure fluid and this group progresses along the working behind the machine step-by-step in a sliding fashion within and over larger bank-push groups of rams.

Abstract: A mine roof support has gap seals in the form of L-shaped plates on its roof cap and goaf shield. The side walls of the plates overlap at the junctures between the roof cap and the goaf shield and these walls are interconnected with pivot connections each of which is composed of complementary components fitted into openings in the walls. The components combine to form a pivot journal and and are locked to one another by a twist catch which can be released by relative rotation of the components.

Abstract: A composite floor plate assembly for locating between side walls of a pan of a scraper-chain conveyor has an access plate fitted into an aperture in a floor plate proper. A locking bar secures the access plate in position. The access plate has the same thickness as the floor plate but lies wholly flush with the floor plate as does the locking bar and the fixings to prevent collision with the scraper-chain assembly.

Abstract: The invention relates to a method for the simultaneous actuation of a plurality of hydraulic consumers by means of intrinsically-safe electro-hydraulic valves. The consumers are connected by hydraulic directional control valves to a pressure line and/or a return line. These hydraulic directional control valves can be connected in a predetermined manner, via pre-control valves to a control line. The pre-control valves are pressureless, and possess electro-magnets with a current consumption of less than 50 milliamps. By connection of a series-connected electro-hydraulic directional control valve means, the pre-control valves are connected to the control line, and at the same time are hydraulically locked.

Abstract: A mobile anode-block cleaning machine has a steerable workshop floor vehicle provided with its own propulsion system and with a cleaning cabin in which anode remnants are freed from melt incrustations with the aid of a separator. The cleaning operation is completed in a chamber, closed to the exterior, provided in the cleaning cabin, the chamber air expediently being cleaned with the aid of a filter. The machine also has a collecting chamber for the storage of the incrustations separated from the anode remnants.

Abstract: A mine roof support has gap seals in the form of L-shaped plates on its roof cap and goaf shield. The side walls of the plates overlap at the junctures between the roof cap and goaf shield and are connected with pivot connections each of which is composed of a pin inserted into apertures in the side walls of the plates. The pin has a peripheral groove at its inner end region which receives an arcuate yoke plate serving as a support. The yoke plate is itself detachably secured in place with a releasable rod permitting the pivot connection to be easily dismantled.

Abstract: A system serves to establish the spatial positions of a cutter head of a tunnel driving machine with precision and monitors and/or controls this position automatically. The system uses a computer-controlled laser beam scanning technique to locate the three-dimensional positions of mirror devices in successive measuring stations spaced along the tunnel.

Abstract: A gearing unit has an input shaft coupled via a gear train and a clutch to an output shaft which can propel a drive chain for a mineral winning machine or plough.The clutch is released by hydraulic pressure and a load sensor operates a valve device to release the clutch should an excessive load occur. The response of the hydraulic system is optimised by using a special fast-switching valve device and by maintaining a certain pressure in a release chamber of the clutch by circulating pressure fluid through the valve device when the clutch connects the drive to the output shaft. This pressure is lower than that necessary to release the clutch and the valve device rapidly switches to increase the pressure should an overload occur.

Abstract: Apparatus for monitoring the working stroke of a hydraulic ram 1 includes an indicator 3 having a housing 24 containing a tubular measuring chamber 25 connected to the hydraulic ram by a hydraulic line 2. The tubular measuring chamber is transparent on at least one side for the observation of the level of hydraulic fluid contained therein. The lower end of the tubular measuring chamber is connected to the hydraulic line leading to the hydraulic ram. The upper end of the tubular measuring chamber is closed by an air-permeable but dust-impermeable member 28.

Abstract: A transfer station assembly is provided for transferring mineral material from a longwall scraper-chain conveyor to a roadway scraper-chain conveyor. The transfer station includes a box frame, in which the upper run of the roadway conveyor is guided between the upper and lower runs of the longwall conveyor. Guide bars are provided for guiding the scrapers of the scraper assembly of the roadway conveyor within the box frame. The guide bars for the roadway conveyor are detachably secured to the box frame so as to be readily releasable and replaceable by other guide bars, whereby roadway conveyors of different types and/or widths can be connected to the box frame.

Abstract: A conveyor channel section or pan is composed of upper and lower components each having U-shaped rolled side walls with inwardly-directed flanges and floor plates. Additional side plates fixed to the exteriors of the side walls of the lower component project upwardly alongside the side walls of the upper component. Recesses in the side plates mate with fittings on the side walls of the upper component and upstanding nuts and bolts secure the fittings in the recesses. The end regions of the pan can be provided with inclined deep pockets formed within welded-in shaped joining pieces which receive toggle-like coupling pieces used to connact adjacent pans together.

Abstract: A gearing unit has a housing containing gearing drivably interconnecting a rotary input to an output shaft used to propel a drive chain of a mineral mining machine. A clutch is provided which is released by hydraulic pressure to disengage the drive automatically should excessive loading occur. A spigot rotatably locked to the shaft provides a fluid passage for hydraulic fluid used to release the clutch and the fluid flow is controlled by an electromagnetic valve. A torsion bar carrying a load sensor is located within the spigot and the sensor provides an electrical signal transferred to control means for operating the valve via a slip-ring system. The torsion bar is rotatably locked to the shaft via a coupling rod disposed within the shaft and a push-in connection. The torsion bar is also rotatably secured to the spigot for easy release therefrom.

Abstract: A scraper-chain conveyor channel section comprises a pair of side walls and a floor plate extending between the side walls and connecting the side walls together. Each of the side walls has upper, lower and intermediate inwardly-extending flanges. The floor plate is connected to the intermediate flanges of the two side walls. Each of the side walls is constituted by an upper profiled bar and a lower profiled bar, each of the profiled bars being a generally U-shaped rolled section. Each of the lower profiled bars has a bottom flange and a top flange parallel to the bottom flange. The top flange of each lower profiled bar forms a support surface for the associated upper profiled bar, and constitutes part of the intermediate flange of the associated side wall. Each of the side walls is provided with a connecting bar for laterally supporting the associated upper profiled bar.