US3906738A - Control systems for use with mineral mining apparatus - Google Patents

Control systems for use with mineral mining apparatus Download PDF

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Publication number
US3906738A
US3906738A US341012A US34101273A US3906738A US 3906738 A US3906738 A US 3906738A US 341012 A US341012 A US 341012A US 34101273 A US34101273 A US 34101273A US 3906738 A US3906738 A US 3906738A
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Prior art keywords
disc
shifting
pressure fluid
automatic
port
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US341012A
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English (en)
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Walter Weirich
Karl Heinz Rosenhovel
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Gewerkschaft Eisenhutte Westfalia GmbH
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Gewerkschaft Eisenhutte Westfalia GmbH
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    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
    • E21D23/00—Mine roof supports for step- by- step movement, e.g. in combination with provisions for shifting of conveyors, mining machines, or guides therefor
    • E21D23/16—Hydraulic or pneumatic features, e.g. circuits, arrangement or adaptation of valves, setting or retracting devices
    • E21D23/26—Hydraulic or pneumatic control
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
    • F15B11/16—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors
    • F15B11/20—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors controlling several interacting or sequentially-operating members

Definitions

  • ABSTRACT A hydraulic control system for controlling the shifting of roof support units and a longwall conveyor in a mineral mining installation.
  • the units are shifted in groups by means of an automatic shifting means known per se which shifts each of the units in the associated group in succession.
  • the control system has control devices operably associated with the first and last units of each group so that the automatic shifting sequence can commence from either the first or the last of the units.
  • Each control device has a disc mounted in a housing and rotatable to three operating positions namely a neutral position whereat no shifting operations occur, an operating position whereat shifting of the conveyor occurs and an automatic position whereat the automatic shifting means is actuated. At each of the operating positions the disc serves to establish communication between pressure fluid boxes in the device via a non-return valve which is manually operated.
  • the devices are interconnected by a pressure fluid conduit which serves, when pressurized, to lock the disc of one of devices when the other device is set to the automatic position and to move the disc of the one device to the neutral position.
  • Each device also has a mechanism to ensure the disc thereof can only rotate in one direction so that it is impossible to change directly from the neutral position to the automatic position.
  • the present invention relates to a control system for controlling the shifting of mineral mining apparatus which includes roof support units sequentially shifted with the aid of automatic shifting means known per se.
  • each of the support units is equipped with a hydraulic control valve, which is usually actuated manually, in order to shift the support units in succession in accordance with the progress of the'mining work.
  • These control valves can be so constructed so that for each unit the removal of pressure from the props of the unit for their retraction the operation of feeding the support unit forward and the resetting of the props is accomplished by switching over the associated control valve.
  • Systems are already known, however, in which each support unit of the mine working is equipped with its own automatic control valve, which when initiated automatically performs the entire support-shifting cycle.
  • each group comprising, for example, 6 15 units.
  • Each of these groups then has an automatic shifting means associated therewith with which all the support units belonging to the group in question can be automatically shifted in succession.
  • Such a shifting means can operate hydraulically, pneumatically or electrically and if necessary the shifting means can be designed to be actuated remotely.
  • This invention is based on the known group sequence control systems, in which a group of support units generally comprising about 6 l and preferably 8 12 support units of a mine working are automatically shifted in the preselected sequence, by selecting or switching on the automatic shifting means associated with the group. To enable all the support units of the group to be shifted in this process, therefore, all that is necessary is to initiate the control sequence, which is then completed automatically, and to ensure that the automatic shifting sequence is not hindred; and proceeds safely until the last support unit of the group has been shifted.
  • a general object of the invention is to provide an improved form of control'system for mining apparatus of the above mentioned kind.
  • a control system for controlling the shifting of mining apparatus which includes roof support units sequentially shifted with the aid of automatic shifting means; said system comprising individual control devices associated with an operational group of the support units and connected to said shifting means so that each device is capable of initiating the automatic shifting sequence and interlock means for inhibiting operation of one of said devices when the other device has initiated said automatic shifting sequence.
  • the first and the tenth unit of the group can each be associated with one of the control devices in such a way that the shifting of the entire group, accomplished by the shifting means and initiated by one of the control devices, can start from either the first or the tenth unit as desired.
  • the shifting of the group of units can thus be effected from either end thereof, rendering the task of the operators considerably easier and safer and enabling the support units to be shifted more rapidly after an associated mining machine has passed.
  • this function is effected automatically by the interlock means when one device is actuated.
  • Each device preferably has an assembly which can be moved into various operative positions whereat in one position the automatic shifting sequence is initiated and in another position the shifting operations occur.
  • the assembly can be moved into a further position whereat shifting of a longwall conveyor is effected by means of pressure fluid passed through the device to the shifting rams, thereof.
  • the interlocking can be effected in various ways, e.g. by mechanically locking the assembly of the one device in its neutral position, i.e. in said another position, so that it cannot be moved, even by the application of force, into the automatic position, i.e. into said one position.
  • the system can be so designed that the assembly of the one device is automatically returned to the neutral position. More particularly, it is possible to arrange that the particular control device which initiated the automatic shift sequence is automatically returned to the neutral position by a control pulse at the end of the automatic shifting cycle which it has initiated.
  • the control system of the invention is preferably constructed as a. purely hydraulic control system.
  • the interlock means then preferably includes a pressure fluid conduit and a locking mechanism operably connected to said conduit and serving to inhibit or preventthe movementof said assembly when the conduit conveys pressure fluid thereto.
  • control devices it is advisable for the control devices to be so designed that the support units can also be shifted by manual control independently of the said automatic shifting means if this proves necessary or desirable for operational reasons. It would also be an easy matter to construct the control devices in such a way that they can be actuated not only manually, but, if necessary, via a hydraulic, pneumatic or electrical remote control arrangement.
  • the assembly at least includes a disc mounted for rotation in a housing to effect selective communication between bores for conveying pressure fluid and a lever connected to said disc for manually effecting said rotation to thereby adopt said operative positions.
  • the locking mechanism may then have a spring-loaded piston which is displaced when subjected to pressure by said conduit to engage the peripheral surface of the disc.
  • the disc can have a recess in its peripheral surface, said recess having one of its defining surfaces engageable with said rod whereby the rod can engage said surface to move the disc from the automatic position to the neutral position.
  • the recess in the disc can be V-shaped and the piston may be located in a tubular structure extending tangentially to the housing for the disc so that the piston rod can move the disc about its axis of rotation.
  • control devices each be provided with means for preventing the disc thereof from rotating in one direction to thereby ensure the disc cannot move directly between the neutral and automatic positions, i.e. without the intermediary of the position whereat shifting of the conveyor occurs.
  • This means may take the form of a spring-loaded pin disposed in a bore extending radially of the disc, the inner surface of the housing surrounding the disc having recesses therein, each recess having a shoulder at one end and tapering therefrom towards the disc to the other end whereby the pin can engage on the shoulder of each of said recesses so as to allow movement of the disc only in said one direction.
  • each control device preferably has a central spigot containing a non-return valve openable by means of a plunger operated by pivotal movement of the lever.
  • This spigot may locate in a recess of a baseplate which leads via bores to a connection on the device for receiving pressure fluid, the disc having a sleeve offset from its central axis and connectible through said valve to said connection, the sleeve being selectively communicatable with further bores in the bascplate as the disc is rotated, the further bores leading to further connections on the device.
  • FIG. 1 is a schematic diagram depicting a mineral mining installation employing a control system made in accordance with the invention
  • FIG. 1A is a schematic diagram showing the hydraulic connections between a mineral mining installation and the control system of the present invention.
  • FIG. 2 is a plan view of a control device used in the control system
  • FIG. 3 is a sectional elevational view of the device, the section being taken along the line III III of FIG. 2;
  • FIG. 4 is a sectional plan view of the device the section being taken along the line IV IV of FIG. 3.
  • FIG. 1 there is shown a mineral mining installation with a conveyor F arranged alongside a longwall mineral face K.
  • a winning machine such as a plough (not shown) is guided on the conveyor F and serves to cut mineral from the face K as it is moved along the conveyor F.
  • roof support units such as frames or chocks which can be of any type. These units, depicted by rectangular boxes in FIG. 1, are shifted from time to time towards the face K, i.e. in the direction of arrow R, as is the conveyor F also, shifting rams being provided for this purpose.
  • the shifting of the support units and the conveyor F is controlled by means of a control system made in accordance with the invention.
  • the units are operably combined into groups in generally known manner.
  • one such group is composed of the units designated 1 10 in FIG. 1; the remainder of the units shown in FIG. 1 forming part of similar other groups.
  • Each group of support units 1 10 has associated therewith.
  • each support unit 1, 2, 9, 10 is equipped with a shifting ram R1, R2, R9, R10, and a prop P1, P2, P9, P10.
  • Each of the rams are connected to the conveyor and are operative on being extended to advance the conveyor toward the longwall face K, provided that the props are also in their extended conditions, so as to wedge the units between the floor and roof. Extension of the rams is achieved by feeding pressure fluid to them along the line Cl.
  • a unit is first released by retracting its prop, retraction of the ram will serve to advance the unit toward the conveyor.
  • the prop may then be extended again to wedge the unit in position.
  • This sequence of operations involving the passage of fluid through lines C2, C3, is controlled automatically by a shifting means M.
  • the shifting means operates to cause unit 2 to go through the .same sequence of operation, and so on until unit 10 is in the advanced condition.
  • the automatic shifting means M is actuable to initiate the above-mentioned operation by a signal along line C5.
  • the process is bidirectional.
  • the frame 10 can also be advanced first by actuating automatic shifting means by a signal on line C6, in which case frame 1 is the last to move.
  • an advance of the group of units, unit by unit may be caused by a signal applied to line C5 or C6.
  • control devices S1 and S2 applying the signals to the lines C5 and C6 must be operated in such a way as to ensure that the shifting means M is not actuated by a signal in line C6, once the sequence of advancing the support units has already commenced following a signal in line C5.
  • control devices S1 and S2 shown in the lower part of FIGS. 1 and 1A.
  • two control devices SI and S2 are provided. Each receives pressure fluid through an inlet P from a main supply line C7, and may return fluid to a receiving tank through an outlet PR and line C8. Three other ports are provided in each device, namely an outlet PA for connection to the line C5 or C6 as the case may be, an outlet RL for connection to the line Cl, and an inlet 63 connected to a line L which may receive fluid from the outlet PA of the other control device.
  • the effect of a signal in the line L is to prevent the other control device from being operated when the first device is set to supply fluid from outlet PA. Accordingly, signals on both lines C5, and C6 are rendered impossible.
  • FIGS. 2 4 show a preferred constructional form for the control devices S1 or S2.
  • each of the devices S1 and S2 has a housing composed of a baseplate 20 connected with screws to a hollow pot-shaped complementary part 21.
  • a packing ring is disposed between the housing part 21 and the baseplate 20.
  • Within the housing part 21 is a disc 22 mounted for rotation therein by means of a roller bearing 37.
  • the bearing 37 is accommodated in a recess in the part 21 which is formed between the main wall of the part 21 and an axial shoulder projecting inwardly of the part 21.
  • the disc 22 has a hollow spigot 23 received within a recess 24 disposed at the centre of the base plate to guide and ensure centralization of the disc 22.
  • the exterior of the spigot 23 carries a sealing ring 25 which engages the inner surface of the recess 24.
  • a non-return valve is disposed within the spigot 23 which is open at its outer end facing the recess 24.
  • This valve is composed of a closure element in the form of a ball 27 biased by a spring 26 onto a seating 33.
  • the seating 33 locates in a recess in the main body of the disc 22.
  • the disc 22 also carries a hollow axial shift 28 which is received within a central opening leading to the outer end face of the part 21 and partly defined by the shoulder thereof.
  • the mating surfaces of the shaft 28 and the opening are provided with sealing or packing rings 29, 3O accommodated in grooves.
  • the shaft 28 has its hollow interior communicating with the recess in the body of the disc 22 adjoining the interior of the spigot 23 providing a passageway through these componant parts.
  • a screw-threaded bushing 31 is received within the shaft 28 and has sealing rings provided on its outer surface for engagement with the interior of the shaft 28.
  • a stepped plug defining interior and exterior chambers joined by radial bores is disposed between the bushing 31 and the valve seating 33.
  • Within the bushing 31 there is disposed a displaceable plunger 32 which is guided through the plug and the seating 33. The plunger 32 can be moved to engage and lift the ball 27 off the seating 33 to thereby open the non-return valve.
  • the wall of the central bore of the bushing 31 receiving the plunger 32 also has sealing rings therein for engaging the exterior of the plunger 32.
  • the displacement of the plunger 32 is effected by means of a lever 34 pivotably supported on a rod 35 carried by or connected to the shaft 28.
  • the lever 34 has a block with a cam surface 36 which is engageable with the outer end of the plunger 32 when the lever 34 is pivoted in the direction of arrow Q in FIG. 3.
  • the plunger 32 is maintained in a position where the ball 27 is lifted off the seating 33 and when the lever 34 is returned to the position depicted in FIG. 3 the ball 27 will be urged back against the seating 33 by the spring 26.
  • the assembly essentially composed of the components 22, 31, 34 and referred to hereinafter as the assembly can be rotated about the axis of the disc 22 by means of the lever 34.
  • the disc 22 has a'bore 38 therein radially offset from its centre and receiving a sleeve 40 therein.
  • the sleeve 40 which is displaceable along the bore 38 to a limited extent, has a sealing ring in a groove in its exterior which engages the interior of the bore 38.
  • a flexible abutment ring 41 is carried by the outer end of the sleeve 40 facing the baseplate 20 so as to engage the latter.
  • the interior of the sleeve 40 and the bore 38 communicate with a bore 39 extending radially through the disc 22 to adjoin the exterior chamber defined by the plug disposed between the seating 33 and the bushing 31.
  • a further mounting plate 42 is connected to the baseplate 20 and packing rings are disposed between these component parts as illustrated in FIG. 3.
  • the plate 42 has an axially-directed blind bore 44 which communicates with an extension of the recess 24 in the baseplate 20, and hence with the valve 33, 27.
  • the bore 44 adjoins a radially directed bore 43 in the plate 42 and the bore 43 terminates in a connection or plug P intended for coupling the main pressure fluid conduit C7 of the associated pressure fluid system.
  • the plate 42 has a further radially directed bore 45 which also terminates in a connection or plug PA which is intended for coupling to the automatic shifting means referred to previously.
  • This bore 45 adjoins a bore 46 extending parallel to the axis of the plate 42 and this bore 46 communicates with a similar parallel through bore 47 in the baseplate 20 leading generally to a chamber defined externally of the spigot 23 and at the rear faceof the disc member 22.
  • the bore 47 is alignable with the interior of the sleeve 40 when the assembly 31, 34, 22 is rotated as described hereinafter.
  • the plate 42 also has a bore 48 extending parallel to its axis and leading via a radially directed conduit to a connection or plug R or PR intended for connection to a main return conduit of the pressure fluid system.
  • the bore 48 aligns with a recess in the baseplate 20 containing a spring loaded plug not described in any detail leading to a return conduit for the shifting rams.
  • FIGS. 1A and 2 shows particularly the various connections of the device with the pressure fluid system.
  • the connection P receives pressure fluid.
  • the connection RL serves to discharge pressure fluid to the line C1 leading to the shifting rams of the conveyor F.
  • the connection PR is the main common outlet for conveying fluid to the return path C8 of the pressure source and the connection PA is the outlet for conveying fluid to the automatic shifting means.
  • the assembly 34, 31, 22 can be placed into one of three rotary control positions, denoted 0, 50 and A, by means of the lever 34.
  • the position 0 is a neutral position whereat the connectors P and RL are isolated or blocked from one another.
  • the position 50 is an operating position in which the connections P and RL communicate so that the shifting rams are pressurized to shift the conveyor F.
  • the position A is for the initiation of the automatic shifting means i.e. to move the units 1 10 in sequence.
  • the connectorRL leads to a bore (not shown) in the baseplate 20 which is aligned with the sleeve 40 when the position 50 is adopted.
  • Means in the form of a locking mechanism, described hereinafter, ensures that the assembly 34, 31, 22 can only be rotated in the direction of arrow T so that the assembly cannot be moved directly between the neutral and automatic positions and hence the automatic shifting of the units 1 10 can only take place after the shifting of the conveyor F.
  • the disc 22 has a radial bore 52 which contains a longitudinally-movable pin 51 biased outwardly of the bore 52 with a spring 53.
  • the inner peripheral wall of. the housing part 21 is provided with two recessed portions 54, 55 offset from one another by about 90. Each portion 54, 55 terminates at a shoulder 56 and tapers in a regular manner, in the direction of rotation T, from the shoulder 57 to merge smoothly with the main parts of the peripheral wall.
  • the assembly 22, 31, 34 is shown in FIG. 4 in the operating position 50 whereat the pin 51 locates on the shoulder 56 of the recessed portion 54 to prevent the assembly from moving other than in the direction of arrow T.
  • the pin When the assembly is moved to the automatic positions A the pin progressively retracts in the bore 52 until it can move outwardly to engage the shoulder 56 of the recessed portion 55, thereby preventing the assembly from being moved back to the operating position 50.
  • the housing part 21 is also provided with a subhousing in the form of a tubular tangential extension 58.
  • the extension 58 has its interior 59 constituting a cylinder which receives a piston 61 therein having a rod projecting towards the disc 22.
  • the end of the cylinder 59 remote from the disc 22 has a connector 63 which is intended for connection to the blocking conduit L (FIG. 1).
  • a spring 62 is provided in the cylinder 58 to bias the piston 61 outwardly away from the disc 22.
  • the device also however employs a more positive locking facility to prevent the automatic position A from being adopted in the presence of a pressure signal in the conduit L.
  • This is achieved with the aid of a V-shaped recess 64 provided in the external peripheral surface of the disc 22.
  • the defining surfaces 65, 66 of the recess 64 extend at about 120 relative to one another. If the assembly 34, 31, 22 is placed in the automatic position A the recess 64 will adopt the position denoted 66 and assuming pressure prevails in the conduit L to displace the piston 61 as discussed above the rod 60 will engage the surface 66 to urge the disc 22 in the direction of arrow T. Hence the assembly cannot adopt the automatic position A when a pressure signal is present in the conduit L.
  • the devices S1 and S2 will be set in the neutral position 0, in which the connection P is blocked from the shifting rams of the conveyor F.
  • the conduit L is not subjected to pressure, so that the assembly 22, 31, 34 of each device S1 and S2 is free to rotate.
  • the next operation is to shift the conveyor F. This is effected by moving the lever 34 of one device S1 or 52 into the operating position 50 and pivoting the lever 34 to open the valve 33, 27.
  • the control device in question now allows hydraulic pressure fluid to be supplied to the shifting rams of the conveyor F.
  • the fluid flows from the connection P through the bores 43 and 44 and the opened valve 33, 27 through the radial bore 39 and into the sleeve 40. From here the fluid flows into the bore (not shown) in the baseplate leading via the connector RL to the shifting rams of the conveyor F.
  • the shifting rams now displace the conveyor F over the section situated in front of the group 1 10 towards the face K in the direction shown by the arrow R in FIG. 1. After the conveyor F is moved the group of units 1 10 can likewise be shifted. This is achieved by partially rotating the assembly 31, 22 34 of control device S1 into the automatic position A and again pivoting the lever 34 to open the valve 33, 27.
  • connection P pressure fluid from the connection P flows through the bores 43, 44, the opened valve 27, 33 and the bore 39 into the sleeve 40. From here the fluid passes into the bore 47 and thence through the bores 46, 45 to the connection PA leading to automatic shifting means which once ac- I tuated automatically shifts the entire group of units 1 10, starting with the first support unit 1 and terminating with the last support unit 10.
  • the shifting means is such that the shifting operation commences with the support unit 1 and terminates with the support unit 10. It is also possible, however, to arrange for the units to be shifted in the reversed order, i.e. starting with the support unit 10 and terminating with the support unit 1.
  • the assembly 31, 34, 22 of the device S1 or S2 by which the shifting of the group 1 10 was originally initiated remains in the automatic position A. Further shifting of the group 1 10 by means of this device S1 or S2 can then only be carried out if the assembly 31, 34, 22 of this device S1 or S2 is moved from the automatic position A in the direction shown by the arrow T in FIG. 4 via the 0 position and the operating position 50, back to the automatic position A to re-initiate the automatic-shifting means.
  • Further shifting of the group 1 10 can also be set up by actuating the other device S1 or S2, in which case the device S1 or S2 which was actuated first before and which is still in the automatic position, is automatically moved from the latter position by means of the rod 60 engaging the surface 66 as described before.
  • the system could also be arranged and constructed however, in such a way that after the completed shifting of the group 1 10 the device S1 or S2 which was moved to the automatic position A to initiate the shifting, is automatically returned to its neutral position 0. In this case, as soon as the shifting process is terminated the assemblies 31, 34, 22 of both devices S are released and operable.
  • a hydraulically operable mine roof support arrangement which comprises a group of roof support units and an automatic shifting means for controlling the advance of the units in an ordered sequence from one or other end of the group, depending upon which of two input lines to the shifting means is pressurized
  • the improvement comprising a control system for initiating the operation of the shifting means, said control system comprising two devices each of which is adapted to supply pressure fluid to a respective one of the two input lines to the shifting means, each device being adapted to be placed in a condition in which pressure fluid may be supplied through the device to the input line and interlock means operable upon one of said devices being placed in the condition aforesaid to prevent the other device being placed in said condition or to reset the said other device in a neutral condition.
  • each device has an assembly which can be moved into various operative positions whereat in one position pressure fluid is supplied to the automatic shifting means and in another position no fluid is so supplied.
  • a system according to claim 2, wherein said assembly can be moved into a further position whereat shifting of a longwall conveyor is effected.
  • said interlock means has a pressure fluid conduit connected between said devices and a locking mechanism for each device which at least inhibits movement of the assembly thereof when the pressure fluid conduit is pressurized.
  • said assembly at least includes a disc mounted for rotation in a housing to effect selective communication between bores for conveying pressure fluid and a lever connected to said disc for manually effecting said rotation to thereby adopt said operative positions.
  • the assembly at least includes a disc mounted for rotation in a housing to effect selective communication between bores for conveying pressure fluid and a lever connected to said disc for manually effecting said rotation to thereby adopt said operative positions and wherein the housing has a tubular extension receiving said piston and extending substantially tangentially to the peripheral surface of the disc so that the rod is directly engageable with the peripheral surface of the disc.
  • the disc carries a non-return valve having a spring-loaded closure element movable to open the valve with the aid of a plunger, the plunger being connected to said lever so that pivotal movement of the lever effects opening of the valve.
  • valve is contained in a spigot provided at the centre of the disc and locating in a recess in a baseplate which leads via bores to a connection on the device for receiving pressure fluid, the disc having a sleeve offset from its central axis and connectible through said valve to said connection, the sleeve being selectively communicatable with further bores in the baseplate as the disc is rotated, the further bores leading to further connections on the device.
  • the disc has a recess in its peripheral surface; said recess having one of its defining surfaces engageable with said rod whereby the rod can move the disc away from said one position to said another position when the conduit conveys pressure fluid to said piston.
  • the preventing means is in the form of a spring-loaded pin disposed in a bore extending radially of the disc, the inner surface of the housing surrounding the disc having recesses therein, each recess having a shoulder at one end and tapering therefrom towards the disc to the other end whereby the pin can engage on the shoulder of each of said recesses so as to allow movement of the disc only in said one direction.
  • a mine roof support control system comprising two control devices, each said device having first, second, third and fourth ports, said first port being connected to a main hydraulic supply conduit, said second port being connected to a conduit to mine roof support shifting rams, said third port being connected to an automatic shifting means and the fourth port being connected to the third port of the said other device, operating means movable to a first position to connect said first port to said second port, and to a second position to connect said first port to said third port, and interlock means responsive to pressure applied at said fourth port to prevent movement of said operating means to said second position.

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  • Engineering & Computer Science (AREA)
  • Mining & Mineral Resources (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Geology (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Fluid-Pressure Circuits (AREA)
  • Chain Conveyers (AREA)
US341012A 1972-03-16 1973-03-14 Control systems for use with mineral mining apparatus Expired - Lifetime US3906738A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE2212686A DE2212686C3 (de) 1972-03-16 1972-03-16 Gruppenfolgesteuerung zum automatischen Rücken einer Ausbaugruppe

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US3906738A true US3906738A (en) 1975-09-23

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US (1) US3906738A (de)
BE (1) BE794193A (de)
DE (1) DE2212686C3 (de)
FR (1) FR2175735B1 (de)
GB (1) GB1420862A (de)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4050256A (en) * 1975-07-29 1977-09-27 Gullick Dobson Limited Mine roof support control systems
US4159671A (en) * 1974-08-20 1979-07-03 Allen Archelaius D Self-advancing mine roof supports
US4327628A (en) * 1977-01-11 1982-05-04 Gewerkschaft Eisenhutte Westialia Hydraulic roof support control system
US4451181A (en) * 1981-03-26 1984-05-29 Gewerkschaft Eisenhutte Westfalia Control systems for mineral mining installations
US4676698A (en) * 1984-02-08 1987-06-30 Hermann Hemscheidt Maschinenfabrik Gmbh & Co. Hydraulic valve control apparatus
US4692067A (en) * 1983-06-21 1987-09-08 Dobson Park Industries Plc. Control systems
CN112524109A (zh) * 2020-12-02 2021-03-19 辽宁工程技术大学 一种液压支架四点起吊平衡的方法

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS53114704A (en) * 1977-02-28 1978-10-06 Taiheiyo Eng Operating device of selfftravelling frame* etc*
DE2851937C2 (de) * 1978-12-01 1986-05-28 Gewerkschaft Eisenhütte Westfalia, 4670 Lünen Steuerventil, insbesondere für einen hydraulischen Schreitausbau in Bergbaubetrieben
GB2095425B (en) * 1981-02-25 1984-06-27 Dobson Park Ind Mine roof support control systems
DE3801593A1 (de) * 1988-01-21 1989-08-03 Hemscheidt Maschf Hermann Gruppensteuerung fuer hydraulischen schreitausbau
DE3824522A1 (de) * 1988-07-20 1990-01-25 Kloeckner Becorit Gmbh Verfahren zum ruecken eines strebausbaues
US5428959A (en) * 1994-08-01 1995-07-04 Illinois Tool Works Inc. Pneumatic control circuit

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US2540710A (en) * 1947-08-21 1951-02-06 Westinghouse Air Brake Co Fluid pressure control apparatus
US2548198A (en) * 1945-11-15 1951-04-10 Charles H Cosnett Dual control for the throttle and reversing means of pressure fluid engines
US2940428A (en) * 1954-08-10 1960-06-14 Bendix Aviat Corp Parallel hydraulic control system
US3207041A (en) * 1961-06-12 1965-09-21 Electro Hydraulics Ltd Hydraulically operated advancing roof support systems and monitoring systems therefor
US3285015A (en) * 1961-11-21 1966-11-15 Carnegie James Mining apparatus
US3319529A (en) * 1963-09-06 1967-05-16 Dowty Mining Equipment Ltd Advanceable roof support assemblies
US3320858A (en) * 1963-06-21 1967-05-23 Dowty Mining Equipment Ltd Roof support assemblies

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US2548198A (en) * 1945-11-15 1951-04-10 Charles H Cosnett Dual control for the throttle and reversing means of pressure fluid engines
US2540710A (en) * 1947-08-21 1951-02-06 Westinghouse Air Brake Co Fluid pressure control apparatus
US2940428A (en) * 1954-08-10 1960-06-14 Bendix Aviat Corp Parallel hydraulic control system
US3207041A (en) * 1961-06-12 1965-09-21 Electro Hydraulics Ltd Hydraulically operated advancing roof support systems and monitoring systems therefor
US3285015A (en) * 1961-11-21 1966-11-15 Carnegie James Mining apparatus
US3320858A (en) * 1963-06-21 1967-05-23 Dowty Mining Equipment Ltd Roof support assemblies
US3319529A (en) * 1963-09-06 1967-05-16 Dowty Mining Equipment Ltd Advanceable roof support assemblies

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US4159671A (en) * 1974-08-20 1979-07-03 Allen Archelaius D Self-advancing mine roof supports
US4050256A (en) * 1975-07-29 1977-09-27 Gullick Dobson Limited Mine roof support control systems
US4327628A (en) * 1977-01-11 1982-05-04 Gewerkschaft Eisenhutte Westialia Hydraulic roof support control system
US4451181A (en) * 1981-03-26 1984-05-29 Gewerkschaft Eisenhutte Westfalia Control systems for mineral mining installations
US4692067A (en) * 1983-06-21 1987-09-08 Dobson Park Industries Plc. Control systems
US4676698A (en) * 1984-02-08 1987-06-30 Hermann Hemscheidt Maschinenfabrik Gmbh & Co. Hydraulic valve control apparatus
CN112524109A (zh) * 2020-12-02 2021-03-19 辽宁工程技术大学 一种液压支架四点起吊平衡的方法

Also Published As

Publication number Publication date
BE794193A (fr) 1973-05-16
FR2175735A1 (de) 1973-10-26
GB1420862A (en) 1976-01-14
FR2175735B1 (de) 1976-08-27
DE2212686A1 (de) 1973-09-20
DE2212686B2 (de) 1978-07-20
DE2212686C3 (de) 1979-03-22

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