Mine Props Patents (Class 91/170MP)
  • Patent number: 5611646
    Abstract: A compact support prop having a pressure limiting valve with a very high flow volume forming a prop head as a valve housing. The pressure limiting valve is integrated into the prop head. Thus, insertion speeds of more than 3 meters per second can be achieved. The drawing and filling valve consists of one or possibly two pilot-controlled check valves which can be easily attached to an outer side of the internal prop. It allows for a quick setting and drawing after removal of the released pressure medium. The released pressure medium flows off via the connection of the pilot-controlled check valve. The connection is provided as a setting gun connection and the released pressure medium can be returned to the inside by this connection.
    Type: Grant
    Filed: March 15, 1995
    Date of Patent: March 18, 1997
    Assignee: Richard Voss Grubenausbau GmbH
    Inventor: Richard Voss
  • Patent number: 5555644
    Abstract: Method and apparatus for eliminating the danger of inadvertent failure of a weight-bearing retraction system, such as a dryer hood retraction system. A load lifted using a fluid cylinder can be easily locked in place against gravity by using a double rod ended cylinder, where the rod end not exerting the force is permitted to move through a clearance hole while the load is being lifted, and is then blocked to prevent the return motion until the load is to be released.
    Type: Grant
    Filed: October 17, 1994
    Date of Patent: September 17, 1996
    Assignee: W.R. Grace & Co.-Conn.
    Inventor: Rodney Voegtline
  • Patent number: 5401123
    Abstract: The control device is adapted to be inserted between the control valves of a pilot device and the pressure-medium consumers (hydraulic prop and hydraulic working cylinder) in an hydraulic self-advancing mine-roof support and is connected to a pressure-medium line and to a return line. The control device comprises a valve block with continuous longitudinal bores for connection to a multiple tubing line leading to the pilot device, the valve block having bores for receiving piloted 3/2-way valves and bores for connection to the directly-controlled working cylinders of the mine-roof support.
    Type: Grant
    Filed: December 20, 1993
    Date of Patent: March 28, 1995
    Assignee: Hermann Hemscheidt Maschinenfabrik GmbH & Co.
    Inventors: Wolfgang Kobow, Werner Reinelt
  • Patent number: 5297901
    Abstract: For use in underground individual prop support, an individual prop valve is provided whose case integrates a return valve for setting, a non-return valve for drawing, and a pressure-limiting valve for securing the prop against overload. The valve case of the pressure-limiting valve is moved hydraulically if the case is also equipped on the drawing side with a coupling piece which has a gripping groove and locking shoulder. A push bolt which is loaded correspondingly by the pressure fluid acts on the valve case and moves it by a predefined length, so that the non-return valve is hereby opened and the pressure fluid is able to flow from the prop interior through the suction pump connection located on the setting side. Here the channels or spaces are proportioned in such a way that an increased amount of pressure fluid may be discharged, whereby this process is supported by a pump connected to the suction pump connection.
    Type: Grant
    Filed: November 9, 1992
    Date of Patent: March 29, 1994
    Assignee: Grubenausbau GmbH
    Inventor: Richard Voss
  • Patent number: 5181451
    Abstract: A control system for longwall face support frames as used in mines, the system comprising pushing rams which are adapted to be actuated at two different pressures (for example, a low pressure of about 70 to 120 bar for non-defined cutting and a high pressure of 120 to 350 bar for defined cutting) with each pushing ram being individually actuatable by a respective non-return valve arrangement, the pushing rams being connected by a common pressure line to an hydraulic pressure unit.
    Type: Grant
    Filed: June 18, 1991
    Date of Patent: January 26, 1993
    Assignee: Hermann Hemscheidt Maschinenfabrik GmbH & Co.
    Inventors: Guy Geuns, Werner Reinelt
  • Patent number: 5157947
    Abstract: A valve device takes the form of a multi-part cartridge with a hollow stepped housing containing a stepped rod. A control piston at one end of the rod is opposed by the force of a main spring in a main chamber remote from the control piston. A valve closure member is axially displaceable relative to the rod. The valve closure member is normally held against a valve seating but pressure on the control piston displaces the rod and causes the valve closure member to be lifted from its seating via stop faces. An auxiliary chamber in the housing leads via a connection to some consumer appliance and forms, the downstream side of the valve. A compensating piston on the rod member opposes a face of the valve closure member open to the auxiliary chamber. A further spring in the auxiliary chamber holds the valve closure member on its seating. The valve can open independently of the control piston should the pressure on the upstream side of the valve exceed the consumer pressure.
    Type: Grant
    Filed: February 16, 1989
    Date of Patent: October 27, 1992
    Assignee: Gewerkschaft Eisenhutte Westfalia GmbH
    Inventors: Walter Weirich, Reiner Stich, Michael Dettmers
  • Patent number: 4946316
    Abstract: A method and device is provided for the moving of a shield-type support trestle 1 having stamps 4, 5 arranged between a roof pressure cap 3 and a lying skid 2, a pushing ram 6 is in the lying skid 2, and control valves 11, 12, 13, 14 for controlling the desired functions of the shield-type support trestle 1. The stamps 4, 5 have an inlet valve 22 and a discharge valve 4. A pressure line 40 is provided between control valve 13 and the pushing ram 6. A valve 51 is provided which is controlled by the pressure in the pressure line 40 and by which interconnects stamp pressure chambers. A manometric switch 48 is arranged on the pressure line 40 and activates an electronic control device 42. In lines 53, 55, and 29 between the stamp pressure chambers and the return line 18, an unlockable reflux valve 54 is provided which is actuated through the electronic control device 42 and the discharge valve 24.
    Type: Grant
    Filed: July 19, 1989
    Date of Patent: August 7, 1990
    Assignee: Klockner-Becorit GmbH
    Inventors: Willy Watermann, Herman-Josef Schulze-Heiming
  • Patent number: 4906143
    Abstract: An electro-hydraulic control system has a valve unit allocated to a roof support (support shield, support trestle or the like) and equipped with electromagnetic valves. The unit is controlled by a control unit via a cable which includes two current supply leads serving as a common current supply for all the electromagnetic valves and at least one data bus through which an actuator connected with the valve unit is actuated from a microprocessor of the control unit. The actuator itself consists preferably of a shift register through which all the electromagnetic valves can be actuated.
    Type: Grant
    Filed: May 9, 1988
    Date of Patent: March 6, 1990
    Assignee: Gewerkschaft Eisenhutte Westfalia GmbH
    Inventors: Willy Kussel, Johannes Konig, Martin Reuter
  • Patent number: 4798417
    Abstract: A method in underground coal mining for separating the upper coal of the seam from the roof during the advancement of the upper sliding cap of a support frame, wherein the front edge of the cap is forced in a plane of the cap between the upper coal to be separated and the rock from which the coal is to be separated. During the advancement of the sliding cap, the sliding cap is alternatingly moved backwardly and forwardly, so that the from edge of the sliding cap separates the upper coal during its forward movement. Alternatively or additionally, when the front edge of the sliding cap contacts the upper coal, alternatingly higher and lower pressure can be admitted to the sliding cap in order to obtain a shaking effect. In this combined method, the sliding cap is advanced, the shaking procedure is carried out as the front edge contacts the upper coal, and the sliding cap is subsequently moved backwardly. The cycle is then repeated several times.
    Type: Grant
    Filed: September 14, 1987
    Date of Patent: January 17, 1989
    Assignee: Bochumer Eisenhutte Heintzmann GmbH & Co. HG
    Inventors: Gunter Blumenthal, Gustav Neu, Karl-Heinz Berger, Siegmar Block
  • Patent number: 4782736
    Abstract: A pressure-control valve is connected to a working cylinder of an hydraulic, walking, mine roof support on one side of the piston in the cylinder. In its function as a pressure-limiting valve, it regulates the pressure in the working cylinder in dependence upon a predetermined pressure in a control conduit which is connected to the pressure chamber of a prop of the mine roof support. Through it a spring-loaded control piston of the pressure-control valve is hydraulically loaded so as to act on a spring-loaded valve closure member in the pressure-control valve. The control piston holds the valve-closure member in the closure position if the pressure in the control conduit exceeds the predetermined pressure. If the pressure in the control conduit drops off, the valve-closure member then regulates the pressure in the working cylinder to a comparatively low value.
    Type: Grant
    Filed: February 4, 1986
    Date of Patent: November 8, 1988
    Assignee: Hermann Hemscheidt Maschinenfabrik GmbH & Co.
    Inventors: Karl Krieger, Werner Reinelt
  • Patent number: 4737052
    Abstract: The invention relates to a distributor for controlling hydraulic distribution between hydraulic consumers of a mine roof support unit and hydraulic supply lines extending along a mine working. The distributor comprises a supply block provided with a plurality of pairs of main hose connections and a plurality of branch hose connections. The hose connections of each pair of main hose connections are connected by a respective main passage. Each branch hose connector is connected to a corresponding main passage by a respective branch passage. The supply block is provided with two sets of shut-off valves, the shut-off valves of one valve set being arranged in the main passages, and the shut-off valves of the other valve set being arranged in the branch passages. The hose connections of each pair of main hose connections are connected into a respective hydraulic supply line, and the branch hose connections are connected to the hydraulic consumers of the roof support unit.
    Type: Grant
    Filed: March 11, 1987
    Date of Patent: April 12, 1988
    Assignee: Gewerkschaft Eisenhutte Westfalia GmbH
    Inventors: Walter Weirich, Bernd Peters
  • Patent number: 4694730
    Abstract: The control valve for the re-setting of the props at a predetermined minimum setting pressure is connected at respective junctions to a high pressure conduit, to the pressure chambers of the props, to the prop-setting conduit and to the return-flow conduit leading to the annular chambers of the props. The spring-loaded closure body is guided displaceably in the valve housing by journals on each of the two sides of the valve cone. The ends of the journals are formed as actuation faces. The valve cone seals off the high pressure junction and the junctions leading to the pressure chambers of the prop and opens only when a predetermined minimum setting pressure at the junction is exceeded. For closure, the control valve is loaded through the junction on the actuation area of the journal with the pressure fluid conducted to the annular chambers of the props.
    Type: Grant
    Filed: October 16, 1986
    Date of Patent: September 22, 1987
    Assignee: Hermann Hemschedit Maschinenfabrik GmbH & Co.
    Inventors: Karl Krieger, Werner Reinelt
  • Patent number: 4692067
    Abstract: A coal cutting machine 13, a conveyor 12 and a plurality of mine roof supports 10 extend along the face 11 of a coal mine. The operation of the hydraulic jacks of the roof supports are controlled by pilot valves which are electrically powered and rotationally driven. For example, motorized or cam operated pilot valves can be used. Such pilot valves use much less energy than valves controlled conventionally by solenoids, and the electricity supply can thus be at an intrinsically safe level.The operation of the pilot valves include unitary operation of a given support, remote operation of one support from another and sequential operation of a series of supports.
    Type: Grant
    Filed: June 18, 1984
    Date of Patent: September 8, 1987
    Assignee: Dobson Park Industries Plc.
    Inventors: Richard Ward, Archelaius D. Allen
  • Patent number: 4657443
    Abstract: An arrangement for supervising and controlling synchronous displacement of respective pistons of two cylinder-and-piston units, especially of an advancement and a roof cap displacement unit of a roof support assembly for use in underground mining, comprises first and second conduit systems each having two branches each connected with one of the piston and annular spaces of a different one of the units; a switching valve interposed between pressure and a return conduits and the first and second conduit systems; and first and second shut-off valves respectively interposed in those of the branches of the first and second conduit systems which lead to the piston spaces.
    Type: Grant
    Filed: March 11, 1986
    Date of Patent: April 14, 1987
    Assignee: Bochumer Eisenhuette Heintzmann GmbH & Co.
    Inventor: Gunter Blumenthal
  • Patent number: 4643392
    Abstract: A valve for use in controlling a plurality of fluid operated functions, for example the functions of a hydraulic mine roof support, comprises a valve body 10, a plurality of valve members 13 each movable independently to carry out a fluid flow control function, a plurality of valve actuating members 21, movable in a direction tending to actuate the valve members 13, and an interposer device 25 movable to prevent at least one of the valve actuating members 21 from actuating its associated valve member 13, thus enabling the valves to be selectively operable.
    Type: Grant
    Filed: January 14, 1985
    Date of Patent: February 17, 1987
    Assignee: Dobson Park Industries Plc.
    Inventor: Richard Ward
  • Patent number: 4639169
    Abstract: A mineral mining installation comprises a roof support unit and an advance mechanism. The roof support unit has a floor sill constituted by two floor girders. The advance mechanism comprises a hydraulic advance ram, the advance ram having a relatively-displaceable cylinder and a piston rod, and a device for selectively limiting the working stroke of the ram. The stroke-limiting device comprises a stop fixed to the cylinder of the advance ram, and an adjustable stop member which is mounted on the side wall of one of the floor girders.
    Type: Grant
    Filed: January 30, 1985
    Date of Patent: January 27, 1987
    Assignee: Gewerkschaft Eisenhutte Westfalia
    Inventors: Kunibert Becker, Rudiger Kirchbrucher, Michael Preuschoff
  • Patent number: 4580594
    Abstract: A valve device is provided for use in a pressurized hydraulic fluid path, for example the hydraulic path of a hydraulic leg of a mine roof support which is required to yield under two different sets of conditions. The valve device has a port 15 for connection to the pressurized hydraulic fluid path, a bleed valve 25 being arranged to permit hydraulic fluid to bleed from the path at a first rate when the pressure in the path exceeds the first limit, for example to permit the hydraulic leg to collapse at a very slow rate, for example as a mine roof converges. There is also a dump valve 20 arranged to permit hydraulic fluid to flow from the path at a second greater rate, for example if a rock burst occurs. Although the dump valve 20 reacts to high pressure surges of fluid, it does not react to low pressure surges because a non-return valve device 30 traps on one side of the dump valve hydraulic fluid which is at a pressure in the region of the first limit.
    Type: Grant
    Filed: December 17, 1984
    Date of Patent: April 8, 1986
    Assignee: Dobson Park Industries Plc
    Inventor: Nigel J. Petts
  • Patent number: 4572709
    Abstract: Apparatus for controlling the working stoke of the hydraulic props of a mine roof support unit is disclosed. The control apparatus comprises a control valve whose input side is connected to a hydraulic pressure line, and whose output side is connected to a working chamber of each of the props via a respective supply line. A sequence valve is provided in the supply line leading to one of the props. The sequence valve is such as to open the associated supply line when subjected to a predetermined hydraulic pressure, this predetermined hydraulic pressure being at least approximately equal to the hydraulic pressure necessary to overcome the resistance to the working stroke of another of the props. The sequence valve has a tubular valve body, a valve closure element mounted within the valve body, and a valve seat positioned within the valve body. A spring is provided for biassing the valve closure element towards the valve seat.
    Type: Grant
    Filed: April 4, 1983
    Date of Patent: February 25, 1986
    Assignee: Gewerkschaft Eisenhutte Westfalia
    Inventors: Walter Weirich, Michael Dettmers
  • Patent number: 4538640
    Abstract: A multiposition selector valve of the rotary type includes a valve body having a single inlet port and a plurality of outlet ports. Fluid communication between the inlet port and any one of the outlet ports is provided via a check valve assembly mounted on the valve body, and via a fluid-providing conduit connected at one end to the inlet port via the check valve. The other end of the conduit is movable in rotary fashion for fluidtight engagement with any one of a plurality of valve seat areas associated with the outlet ports. The valve seat areas are integral portions of a flat metal disk that can be removed from the valve body to facilitate maintenance of the valve. A single handle rotates the conduit through its various selected outlet positions and operates the check valve assembly to open and close the valve at selected outlet positions.
    Type: Grant
    Filed: September 30, 1982
    Date of Patent: September 3, 1985
    Assignee: Teledyne Republic Manufacturing
    Inventor: Richard C. Acker
  • Patent number: 4518285
    Abstract: A control system for longwall mining roof supports which are controlled in dependence on the position of the mining machine at any time. All of the roof supports are connected to a central computer via common conductors. Each of the roof supports includes a control unit having a code corresponding to the number of that support. This code serves as an address and enables the central computer to transmit its control command signals positively, in response to the mining machine position signals, through an appropriate address control unit for a particular roof support. In order to enable roof supports to be actuated manually also, the control units of all of the roof supports are connected to the central computer by two common conductors, one of which carries an automatic enable signal and the other of which carries a manual enable signal.
    Type: Grant
    Filed: February 28, 1983
    Date of Patent: May 21, 1985
    Assignee: Gebr. Eickhoff Maschinenfabrik und Eisengiesserei mbH
    Inventors: Karl-Heinz Weber, Wolfgang Beckmann, Hartmut Gebauer
  • Patent number: 4485724
    Abstract: Hydraulic control apparatus serves to operate roof support props of a mineral mining installation. An automatic setting arrangement with a valve device ensures the props become set against the roof with a high uniform force by connecting a prop pressure chamber to a pressure fluid source once a threshold pressure is exceeded signifying the prop has been extended. To disable the automatic setting arrangement during prop retraction the valve device thereof is provided with a control piston which is subjected to pressure during retraction to oppose the action of another control piston which responds to the threshold pressure.
    Type: Grant
    Filed: June 25, 1982
    Date of Patent: December 4, 1984
    Assignee: Gewerkschaft Eisenhutte Westfalia
    Inventors: Bayramadi Demircan, Willy Kussel
  • Patent number: 4476898
    Abstract: A control device for the sequential control of an advancing mine-roof support comprising pressure-controlled directional control valves alternately connectable to a high pressure line and to a return line in order to convert a pressure pulse into a switching step at the main control unit of the advancing mine-roof support and for transmitting an answering pressure pulse signalling the completion of the workstage for continuing the sequence.
    Type: Grant
    Filed: March 19, 1982
    Date of Patent: October 16, 1984
    Assignee: Hermann Hemscheidt Maschinenfabrik GmbH & Co.
    Inventors: Karl Krieger, Gunther Kuschke
  • Patent number: 4473324
    Abstract: A mine roof support includes a first liquid supply means having a first control valve for connecting a source of liquid under pressure to the legs of the support. The support is also provided with a second control valve which is actuatable, when the pressure of the liquid being supplied to the legs attains a value below the setting pressure for the legs, to connect the legs to a source of liquid under pressure by way of a second liquid supply means. Time-delay means is operable on the second control valve to cause it to close when a predetermined time has elapsed after the pressure in the legs has reached the setting pressure.
    Type: Grant
    Filed: February 23, 1983
    Date of Patent: September 25, 1984
    Assignee: Dowty Mining Equipment Limited
    Inventor: Stephen P. Cook
  • Patent number: 4465408
    Abstract: A control line connects an annular space in an auxiliary hydraulic cylinder of an hydraulically-movable mine-roof support (the auxiliary cylinder being provided to advance a forward, auxiliary, roof-support canopy in the direction of the working face of a mine) to the displacement space of an hydraulic measuring cylinder which is longitudinally displaceable in a direction parallel to the hydraulic advancing cylinder in order to advance the auxiliary roof-support canopy, which is pivoted to the main roof-support canopy, in synchronism with the advancing cylinder mounted in the base of the mine-roof support and attached to an abutment on the working face side of the support. A control valve is connected to the control line and responds to the control line pressure in such a way that, when the pressure falls, it supplies pressurized fluid into the pressure space of the auxiliary cylinder to extend the piston rod thereof, and shuts off again when the pressure increases.
    Type: Grant
    Filed: April 29, 1983
    Date of Patent: August 14, 1984
    Assignee: Hermann Hemscheidt Maschinenfabrik GmbH & Co.
    Inventors: Karl Krieger, Gunter Kuschke, Werner Reinelt
  • Patent number: 4440522
    Abstract: A roof support unit for a longwall mineral mining installation has a roof shield supported above a floor sill. A first hydraulic ram is provided for advancing the roof support unit. The roof shield is provided with a forward extension which is advanceable by means of a second hydraulic advance ram. A hydraulic control arrangement, which includes the two hydraulic advance rams is provided for controlling the advance of the roof shield extension in dependence upon the working stroke of the first hydraulic advance ram. The control arrangement is such that the amount of hydraulic fluid supplied to one of the pressure chambers of the second hydraulic advance ram is dependent upon the amount of hydraulic fluid expelled from one of the pressure chambers of the first hydraulic advance ram during the working stroke of the first hydraulic advance ram.
    Type: Grant
    Filed: December 19, 1980
    Date of Patent: April 3, 1984
    Assignee: Gewerkschaft Eisenhutte Westfalia
    Inventors: Michael Dettmers, Walter Weirich
  • Patent number: 4422808
    Abstract: An assembly of mine roof supports each of which has a control member and a hydraulically-operated member, e.g. a cantilever. The cantilevers operate one after the other in a predetermined sequence in response to actuation of one of the control members.Each cantilever is associated with a pressure-operated control valve and two serially-connected control valves which normally prevent operation of a cantilever in response to actuation of a control member unless the next-before cantilever in the series has completed its operation and the control member which caused that next-before cantilever to operate has been actuated.
    Type: Grant
    Filed: July 7, 1982
    Date of Patent: December 27, 1983
    Assignee: Dowty Mining Equipment Limited
    Inventor: Stephen P. Cook
  • Patent number: 4394875
    Abstract: A hydraulic control system for a mine roof support unit has a control valve assembly for controlling the hydraulic appliances of the unit, and an actuator for actuating the control valve assembly. The actuator has a valve block provided with a plurality of pairs of spool valves. The spool valves of each pair are detachably fixed in a pair of generally parallel bores formed in the valve block. Each pair of spool valves is provided with a respective rocker arm for actuating purposes. Each of the rocker arms is mounted on a respective cover plate, which covers the mouths of the corresponding pair of bores, and which is detachably secured to the valve block.
    Type: Grant
    Filed: March 24, 1981
    Date of Patent: July 26, 1983
    Assignee: Gewerkschaft Eisenhutte Westfalla
    Inventors: Walter Weirich, Werner Grommas
  • Patent number: 4379662
    Abstract: An improved control for an underground mining working support unit arrangement of the type having an adjacent support unit arrangement hydraulically connectable to the working support unit arrangement in which a plurality of hydraulic supports support load points, it is disclosed wherein the hydraulic supports are successively connectable to several of the load points with a reversing valve operable to alternately connect control valves to selected hydraulic supports.
    Type: Grant
    Filed: June 29, 1981
    Date of Patent: April 12, 1983
    Assignee: Thyssen Industrie AG
    Inventor: Siegmar Block
  • Patent number: 4306822
    Abstract: 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.
    Type: Grant
    Filed: July 26, 1979
    Date of Patent: December 22, 1981
    Assignee: Gewerkschaft Eisenhutte Westfalia
    Inventors: Walter Weirich, Harry Rosenberg
  • Patent number: 4299517
    Abstract: The mine roof supporting structure comprises hydraulic props (3) which are pressing a swivelling cap (8) against the mine roof. A link lever (5) is pivotally linked to the floor frame (1) and a shield (4) is pivotally linked to the link lever (5) and to the cap (8). The shield (4) is pulled in direction to the floor frame (1) by means of a hydraulic tension strut (14). The working chamber (24) of the tension strut (16), which working chamber includes the piston rod and is facing the pivotal point (12) of the tension strut (16) to the shield (4), can be brought in connection with the supply conduit (19) for feeding pressurized fluid to the props (3) via a spring loaded check valve (22, 23), noting that the opening pressure of the spring (22) is smaller than the final supporting pressure exerted by the props (3). The piston surface of the working chamber (24) is smaller than the piston surface (4) delimiting the working chamber of the props (3).
    Type: Grant
    Filed: January 23, 1980
    Date of Patent: November 10, 1981
    Assignee: Voest-Alpine Aktiengesellschaft
    Inventors: Gottfried Siebenhofer, Heinrich Suessenbeck, Alfred Zitz
  • Patent number: 4247226
    Abstract: In a mine installation which employs a winning machine moved back and forth along a guide in a working and coupled via shifting rams to roof supports, the invention provides a hydraulic fluid supply conduit system for supplying the pressure fluid for operating the shifting rams and the props of the roof supports. The system employs a first conduit containing fluid at a pressure of 300 to 400 bars for setting the props of the roof supports, a second conduit containing fluid at a pressure of 100 to 200 bars for use as a robbing aid during retraction of the props, a third conduit containing fluid at a pressure of 100 to 200 bars for operating the shifting rams and a common fluid return conduit. The conduits are laid along the working and the first and the second or third conduits are fed by separate pumps in a heading or gallery while the third or second conduit is connected via a pressure-reducing valve to the pump feeding the first conduit.
    Type: Grant
    Filed: December 12, 1978
    Date of Patent: January 27, 1981
    Assignee: Gewerkschaft Eisenhutte Westfalia
    Inventors: Walter Weirich, Michael Dettmers
  • Patent number: 4225271
    Abstract: A control arrangement for a hydraulically operated mine roof support having first and second consumers which require smaller and larger amount of the working medium per time unit, respectively, has first control elements for the first consumers and second control elements for the second consumers. The first control elements include a first bundle of hoses having a small inner diameter and arranged to select and apply pressure to the first consumers directly from a neighboring mine roof support. The second control elements include a second bundle of hoses with a small inner diameter, main control valves indirectly remotely controlled through the second bundle of hoses and arranged to select the second consumers, and conduits extending between the second consumers and the main control valves and arranged to apply pressure to the former. The conduits have an inner diameter which exceeds that of the hoses of the first and second bundles.
    Type: Grant
    Filed: February 5, 1979
    Date of Patent: September 30, 1980
    Assignee: Bochmer Eisennuette Heintzmann GmbH
    Inventor: Ernst-Gunter Nerlich
  • Patent number: 4159671
    Abstract: A self-advancing mine roof support is provided, in addition to the normal manually operable control valve means for controlling raising and lowering of the roof-engaging structure of the support and operation of the advancing means, with an automatic sequence control valve means operable in response to a control signal from a position removed from the support, for example from an adjacent support, and an isolating valve means arranged so that control of the various operations can be effected either by means of the manually operable means or from the safety of a location spaced away from the support being controlled by means of the automatic valve means each independently of the other.
    Type: Grant
    Filed: December 2, 1977
    Date of Patent: July 3, 1979
    Inventor: Archelaius D. Allen
  • Patent number: 4155375
    Abstract: A multiple valve control device for use with a hydraulic walking mine-roof support frame, comprising a valve housing containing control valves which are disposed concentrically to a central axis around a central filter into which an axially-extending control-medium feed duct enters and from which radial bores extend in a star pattern towards the control valves, the said control valves, which are provided with valve pistons, being actuated via operating members from the valve-housing endface which is provided with a cover.
    Type: Grant
    Filed: May 18, 1977
    Date of Patent: May 22, 1979
    Assignee: Hermann Hemscheidt Maschinenfabrik
    Inventors: Karl Krieger, Horst Schurmann
  • Patent number: 4095616
    Abstract: An hydraulic controller comprising: a casing; first and second inlets and a plurality of outlets associated with the casing; a flow-directing member rotatable in the casing; first and second passages extending through the flow-directing member, the flow-directing member being rotatable in the casing to each of a plurality of selected positions for directing liquid from the said inlets to selected ones of the outlets by way of said passages, each said first and second passage having an inlet end connected to a respective one of the first and second casing inlets, and having an outlet end connected to a selected one of the said several casing outlets according to the selected position of the said flow-directing member; first and second valves mounted in the flow-directing member and movable to open and close said first and second passages respectively; and locking means which operate in at least one of the said selected positions of the flow-directing member to prevent movement of the said first valve to a posi
    Type: Grant
    Filed: November 22, 1976
    Date of Patent: June 20, 1978
    Assignee: Hermann Hemscheidt Maschinenfabrik
    Inventor: Karl Krieger
  • Patent number: 4089182
    Abstract: Equipment for remotely operating by transmitted signals self-advancing supports which are used with a shearer at a long-walled pit face in a coal mine comprises electromagnetic valves, one of which is connected to a hydraulic cylinder for lowering the roof plate of a self-advancing support and moving the support toward the pit face and the other of which is connected to another hydraulic cylinder for lifting the roof plate of the support, a signal converter and a receiver are connected through a cable to the electromagnetic valves including those of the other self-advancing supports in such a manner that each of the electromagnetic valves is specified through the matrix circuit system; and a portable transmitter is provided for transmitting operation signals to the receiver through the radio system.
    Type: Grant
    Filed: December 15, 1976
    Date of Patent: May 16, 1978
    Assignee: Taiheiyo Engineering Inc.
    Inventors: Ken Takahashi, Hideo Inoue
  • Patent number: 3985064
    Abstract: A device for displaceably supporting a body in relation to a support surface comprising at least two elastic elements positionable between the support surface and a surface of the body and separately expansible and contractible in a direction towards and from the support surface and the body surface and means for alternately expansing and contracting the elastic elements, the elastic elements thereby being alternately loaded by and unloaded from the weight of the body, the body being displaceable substantially parallel with the support surface by means of elastic shearing in the elastic element at the moment loaded by and supporting the body, and the means for expansing and contracting the elements being adapted to contract and unload the loaded element after a predetermined deformation thereof and to expanse the other element to a loaded position, the unloaded element thereby elastically resuming its non-deformed position.
    Type: Grant
    Filed: May 19, 1975
    Date of Patent: October 12, 1976
    Inventor: Lars Johnson