Gewerkschaft Eisenhutte Westfalia, Gmbh

Harry Rosenberg

Walter Weirich

Kunibert Becker

Lubomir Plevak

Gunter Lagodka

Karl-Heinz Plester

Friedrich Eggenstein

Burckhardt Elsner

Gunter Terhorst

Michael Dettmers

Bernd Peters

Jurgen Dodt

Thomas Trumper

Egon Wojaczek

Gerd Dunkel

Norbert Holken

Klaus Seeberger

Wolfgang Stradtmann

To increase the height of operation of a shield type roof support an attachment is fitted to the floor sill or to each of a pair of spaced-apart floor skids. The attachment has side walls with bores for receiving pivot pins used to link the attachment to the floor sill or skid and to guide levers connected to the goaf shield. A transverse body extends between the side walls and defines a socket for forming part of a ball-and-socket joint connecting the attachment to a hydraulic prop. The side walls of the attachment have under surfaces which rest on a support surface of the skid or sill near the working face.

Roof supports

A mine roof support has a slidable extension at the front end of an auxiliary roof cap pivoted for swinging up and down on a main cap. To prevent the extension from being extended when the angle of inclination of the auxiliary cap is too high an insulative cylindrical block is fitted to say the auxiliary cap to partially rotate as the auxiliary cap pivots. A flattened region on the block supports a metallic plate and indexes as the auxiliary cap pivots. A resiliently-mounted proximity switch on the main cap senses the presence of the plate and produces a signal to prevent the extension from being extended.

Multi-part roof-contacting structures of mine roof supports

A mine roof support unit includes a pair of generally parallel floor girders, and an advance mechanism positioned between the floor girders. The advance mechanism comprises a hydraulic advance ram and a guide rod system. The advance ram is pivotally connected between the guide rod system and a cross member which interconnects the floor girders. The guide rod system is attachable to a longwall conveyor positioned adjacent to a work face. The cross member is engageable with the floor girders in such a manner that the floor girders are relatively displaceable in a vertical direction. Each of the floor girders is provided with a respective hydraulic lifting ram, the arrangement being such that the lifting rams can be operated to lift one of the floor girders relative to the other floor girder.

Mine roof support unit

An electro-hydraulic control system for an underground mineral mining installation employs individual control assemblies and devices on a series of support units which are interconnected to one another and to a central control station via lines conveying electrical control signals. Manually-operable selector switches on the units enable groups of the support units to be operated in sequence at will by operating the switches of adjacent units outside the group.

Control systems for mineral mining installations

A mineral mining installation includes a longwall conveyor and a plurality of roof support units positioned side-by-side on the goaf side of the conveyor. The conveyor is braced longitudinally by a block bracing system having a plurality of hydraulic bracing rams each of which is disposed at an acute angle to the conveyor. The bracing rams act between the conveyor and floor girders of the roof support units. Each bracing ram is attached to a respective floor girder by means of a bracket. Each bracket has first and second bracket parts welded together, the first bracket part comprising means for connecting the bracket to its floor girder, and the second bracket part forming an extension of the first bracket part and carrying a pivot joint member for pivotally supporting the cylinder of the associated bracing ram. The first bracket part is a standard cast member, to which second bracket parts of differing lengths can be welded.

Mineral mining installation

A longwall mineral mining installation has a conveyor and a plurality of roof support units positioned side-by-side on the goaf side of the conveyor. Each roof support unit has a roof shield having an advanceable shield extension. Each unit has a first hydraulic ram for extending its shield extension, and a second hydraulic ram for advancing the conveyor. The extension of each first ram is controlled in dependence upon the retraction of one of the second rams (either the second ram of the same unit or that of an adjacent unit). This control is effected by controlling the supply of pressurized hydraulic fluid to the first rams. In one embodiment this is carried out by a control valve which has a spring-loaded plunger which engages with a series of equispaced cams on the movable cylinder of the associated second ram. In another embodiment, the piston rods of the rams are provided with series of equispaced magnets. The cylinders of the rams are provided with sensors, which sense the magnets and generate control signals. A control box is provided to direct the control signals to control valves associated with the rams, so that the first rams are extended by the same distance as that through which the second rams are retracted.

A hydraulic control system, particularly for controlling the operation of roof support props of a mine working, employs control devices operated manually to feed pressure fluid to the working chambers of the props to effect extension or retraction thereof. A two-state valve device is operated when the props are extended to ensure that the correct setting pressure is established. This valve device has a control piston which is actuated to cause the device to establish independent connection between the main fluid pressure line and the associated working chambers of the props charged with fluid by the initial operation of the control devices. The connection established by the valve device is maintained even if the control devices break connection between the chambers and the pressure line. When the correct setting pressure is reached, a further control piston of the valve device is actuated to break the connection established by the valve device ready for the next operative cycle.

Hydraulic control systems for mining apparatus

A device for limiting the stroke of a hydraulic ram of mining apparatus employs a segmental stop which partly surrounds the piston rod of the ram. The stop locates between the cylinder of the ram and a head piece at the end of the piston rod. The cylinder of the ram makes contact with the stop during retraction of the ram thereby limiting the stroke of the ram. The stop is connected to the head piece via replaceable or adjustable pins. These pins permit the distance between the head piece and the stop element to be altered at will. The connection pins also enable the stop to be arranged to partly surround the piston rod periphery over different regions thereof.

Devices for limiting the stroke of a hydraulic ram used in mining

A control unit/hydraulic control mechanism for controlling the hydraulic working appliances of a mine roof support unit has a control unit mounted on one side of a distributor plate, and a valve block mounted on the other side of the distributor plate. The distributor plate and the valve block constitute the hydraulic control mechanism, the valve block being constituted by a stack of pilot-operated hydraulic control valves. The control unit has a protective casing defining first and second chambers. The first chamber accomodates a plurality of electromagnetic valves. The second chamber constitutes a lead-through chamber for leading electric cables to the electromagnetic valves. The second chamber is provided with a respective socket for each of the electric cables. Each of the sockets is shaped to mate with a complementary member attached to the associated electric cable, whereby the electric cables can be connected to the control unit so as to resist tensile forces, and in such a manner that the interior of the second chamber is sealed with respect to the external atmosphere.

Control unit for an electro-hydraulic roof support control arrangement

Hydraulic control means are provided for controlling an auxiliary shield positioned at one side of the roof shield of a mine roof support unit. The auxiliary shield is moved laterally of its roof shield by means of three hydraulic rams and the roof shield is supported by hydraulic props. The hydraulic control means comprises a control valve device and two pilot check valves. One pilot check valve is positioned in a line leading from the control valve device to two hydraulic rams which act in tandem. The other pilot check valve is positioned in a line leading from the control valve device to the other hydraulic ram. The pilot check valves are actuated in dependence upon the pressurization of the hydraulic props whereby the hydraulic rams are depressurised when the props are pressurized and vice versa.

Hydraulic control means

A mine roof support has a roof-engaging frame structure supported by hydraulic props on a floor frame and pivotably linked to a goaf shield. The roof frame and goaf shield have L-shaped seal plates at their sides. The seal plates are subjected to a lateral-outwardly-biasing spring force by means of springs and push rods accommodated in guide bores in both the roof frame and goaf shield. To adjust the distance between the plates, there are piston and cylinder units and coupling rods likewise accommodated in guide bores in both the roof frame and goaf shield. The seal plates of the roof frame overlap with those of the goaf shield. The plates are reduced in thickness at their overlapping regions and are pivotably interconnected thereat to correspond to the pivotal connection between the roof frame and the goaf shield. To facilitate assembly in situ, detachable push-in pins are located in bores in the coupling rods and push rods and in lower transverse walls of both the roof frame and goaf-shield. The pins fix the seal plates in a set position with clearance between the overlapping regions of the plates.

Seals for mine roof supports

A roof support unit for use in a mineral mining working has a roof shield supported on a floor sill by means of at least two hydraulic props. A goaf shield is pivotally linked to both the roof shield and the floor sill. At least one of the hydraulic props is inclined towards the face-side of the unit and engages the roof shield. At least one of the hydraulic props is inclined towards the goaf-side of the unit and engages the roof shield.

Roof support unit

The invention relates to a mine roof support assembly for use in winning mineral material from a mineral mining working having a mineral face. The assembly comprises three roof support units positioned side-by-side along the face, and a goaf shield common to the three units. Each of the roof support units has a roof shield supported on a floor sill. The goaf shield is adjustable in height so as to extend from the floor to the roof of the working. Advance means are provided for advancing the roof support units towards the face, and further advance means are provided for advancing the goaf shield to follow up the advance of the roof support units. The further advance means acts between the goaf shield and the roof support units, and is such as to advance the goaf shield by a distance greater than the distance through which the advance means advances the roof support units.

Mine roof support assembly

A hydraulic control system is provided for a roof support unit of an underground mining installation. The roof support unit is provided with a roof cap supported by hydraulic props. The control system comprises a valve for controlling the supply of pressurized hydraulic fluid to the props, and an actuator for closing the valve when the props have been retracted by a predetermined amount.

Growing community of inventors

Ludinghausen, Germany

Harry Rosenberg