Abstract: In a hydraulic shield support system, a plurality of pressure intensifiers are respectively provided for a plurality of hydraulic props. Each pressure intensifier is operated to increase a system pressure to an increased pressure for supplying fluid at the increased pressure to a pressure chamber of the associated hydraulic prop. The plurality of pressure sensors measure the pressures of the fluid supplied to the respective hydraulic props. A control unit sets a plurality of desired pressures for the plurality of hydraulic props, and stops operation of the respective pressure intensifiers when the set desired pressure has been reached.

Abstract: In a hydraulic shield support system, a plurality of pressure intensifiers are respectively provided for a plurality of hydraulic props. Each pressure intensifier is operated to increase a system pressure to an increased pressure for supplying fluid at the increased pressure to a pressure chamber of the associated hydraulic prop. The plurality of pressure sensors measure the pressures of the fluid supplied to the respective hydraulic props. A control unit sets a plurality of desired pressures for the plurality of hydraulic props, and stops operation of the respective pressure intensifiers when the set desired pressure has been reached.

Abstract: A plug-in connection for hydraulic hose lines includes a first plug connector having a circumferential groove on a plug-in nipple, a plug-in sleeve having two transverse bores, and a fork-shaped coupling bracket. The coupling bracket has two bracket portions and one bracket curve, which may be being inserted into the transverse bores for locking the plug-in connection to the bracket portions and penetrate the groove transversely with respect to the plug-in axis. A retaining element for retaining the coupling bracket is also provided and includes an accommodating portion for the bracket curve, two holding arms which are spaced apart from each other and connected by a base at rear ends of the holding arms facing the accommodating portion, and which define at front ends a mounting mouth which can be slipped onto the plug-in nipple and/or the plug-in sleeve in a transverse manner with respect to the plug-in axis.

Abstract: A water system for the admission of pressurized water to spray systems arranged on a powered support assembly for underground mining, having at least one spray system for plow or shearer track spraying and having at least one further spray system for goaf space spraying, canopy spraying and side spraying. A central water line feeds spray nozzles of the spray systems. To increase the operating reliability of the water system and thus of the powered support assembly, the control valves for the spray systems are accommodated in a spray valve block which is provided with a connection for the water line and which can be arranged on the powered support assembly as a unit separated from a hydraulic valve block.

Abstract: A water system for the admission of pressurized water to spray systems arranged on a powered support assembly for underground mining, having at least one spray system for plow or shearer track spraying and having at least one further spray system for goaf space spraying, canopy spraying and side spraying. A central water line feeds spray nozzles of the spray systems. To increase the operating reliability of the water system and thus of the powered support assembly, the control valves for the spray systems are accommodated in a spray valve block which is provided with a connection for the water line and can be arranged on the powered support assembly as a unit separated from a hydraulic valve block.

Abstract: A hydraulic shield support is disclosed with at least two adjustable-length hydraulic props supporting a dedicated shield, which are connected through a control bank to a hydraulic fluid supply and borne on base shoes, and to which a pressure in excess of the pressure of the hydraulic fluid may be applied in the set condition of the shield support. In order to provide almost any pressure level at each shield support at a deep face in a simple way, the shield support has at least one pressure intensifier located in a hydraulic pipe system between the hydraulic fluid supply and the hydraulic props, with an oscillating intensifier piston in the form a differential piston effecting the increase in pressure. The low pressure inlet of the pressure intensifier is connected to the setting pressure pipes upstream, and its high-pressure outlet downstream, of a hydraulically-releasable non-return valve.

Abstract: An electro-hydraulic assembly for use in underground mining is disclosed. The assembly includes a hydraulic component, such as a valve block for an underground self-advancing roof support, as well as actuators and/or sensors which have a housing and can be connected or are connected via a data-transmission system to a control unit. A function (e.g. withdrawing the support, setting, advancing, or the like) can be activated at the hydraulic component by each actuator, and/or a hydraulic state associated with a measuring point of the hydraulic component or another measured variable associated with the self-advancing roof support can be measured by each sensor. A reader unit is associated with each actuator and/or sensor in its respective housing, and an information element or transponder is associated with the hydraulic component for each function, each control valve, or each measuring point.

Abstract: The present invention relates to a pilot control valve, especially for use in mining hydraulics. The valve has a valve insert constructed as a valve cartridge, whose single or multipart valve housing has an input entry 17 for pressure fluid P, a connection opening 18 for a load connection A, an output opening 19, opening into the return flow T and an axial boring 21 to accept a valve closing body 20 provided with a closing surface, which can be lifted from a valve sealing seat 31 arranged between the entry opening 17 and the connection opening 18 by means of an electro-magnetic or piezo-electric switching device which can be fastened onto the valve housing. With the lifting movement of the valve closing body 20 from the valve sealing seat 31 is coupled an at least two part closing mechanism for their separation arranged between the connection opening 18 and the output opening 19.

Abstract: A piezoelectric actuator unit 10 for valve switching has a piezoelectric element changing its size on the application of a control voltage for switching the valve. So as to ensure a Totmann (safety) function of the valve and a fast return of the piezoelectric element into its initial position, the piezoelectric actuator unit 10 comprises a discharge circuit with at least one discharge element 21, 31 connected to the piezoelectric element 11. Discharge of the piezoelectric element is effected when the actuator is in its initial, safe position. The discharge circuit has to be switched actively so as to be able to exert a maximum stroke with the piezoelectric actuator.

Abstract: An electrohydraulic control device for use in the hydraulic systems of advancing support frames of underground mining equipment, which can be switched by means of switching plungers of electromagnets (24), and the directional control valves (3, 4) are put together from pilot control valve (14) and main control valves (3) arranged on a common axis, where by the pilot control valve (4) switches the main control valve (3) by means of a separate pressure medium supply to be found on an additional control pressure line, in which accepting borings (2) are suited for the acceptance of main control and pilot control valves (3, 4) constructed as cartridges which are plugged together.

Abstract: A hydraulic shield support is disclosed with at least two adjustable-length hydraulic props supporting a dedicated shield, which are connected through a control bank to a hydraulic fluid supply and borne on base shoes, and to which a pressure in excess of the pressure of the hydraulic fluid may be applied in the set condition of the shield support. In order to provide almost any pressure level at each shield support at a deep face in a simple way, the shield support has at least one pressure intensifier located in a hydraulic pipe system between the hydraulic fluid supply and the hydraulic props, with an oscillating intensifier piston in the form a differential piston effecting the increase in pressure. The low pressure inlet of the pressure intensifier is connected to the setting pressure pipes upstream, and its high-pressure outlet downstream, of a hydraulically-releasable non-return valve.

Abstract: An electro-hydraulic assembly for use in underground mining is disclosed. The assembly includes a hydraulic component, such as a valve block for an underground self-advancing roof support, as well as actuators and/or sensors which have a housing and can be connected or are connected via a data-transmission system to a control unit. A function (e.g. withdrawing the support, setting, advancing, or the like) can be activated at the hydraulic component by each actuator, and/or a hydraulic state associated with a measuring point of the hydraulic component or another measured variable associated with the self-advancing roof support can be measured by each sensor. A reader unit is associated with each actuator and/or sensor in its respective housing, and an information element or transponder is associated with the hydraulic component for each function, each control valve, or each measuring point.

Abstract: A solenoid operated hydraulic valve for electro-hydraulic controlled underground mining installations such as advancing support frame controllers, with an actuator housing holding coil bodies, an armature, a magnetizable core, and an operating pin of at least two solenoids. The head end for the operating pins of each solenoid has a cut-out for an operating stroke adjuster. A head plate removable from the actuator housing is provided with a manual operating device for each operating pin and is fastened to the head end of the actuator housing with a head seal between them, a removable valve block accepting the hydraulic multi-way valves and an interposed base seal fastened to the actuator housing base. A housing having a socket connects to an intrinsically safe current supply and accepts the operating electronics for the solenoids, and is located on the side of the actuator housing. In each head end cut-out, an electronic protective circuit for the associated coil body is arranged.

Abstract: The present invention relates to an electrohydraulic control system (10) for an underground support system, with a valve block (1) which accepts grouped electrically-operated actuators for example electro-magnets (2, 2′) and several control valves of hydraulic valves switched with these electro-magnets and with a circuit board (7) containing an electronic circuit to which all the actuators (2, 2′) of the valve block (1) are connected through a disconnectable plug-in connection. The circuit board (7) is connected via a cable (21) to a controller (20) for data communication in the support system. The invention allows simultaneous connection of all the electro-magnets (2,2′) with the circuit board (7). For this purpose the circuit board (7) is located in a hood-type enclosure part (9) which is attachable to the back (3) of the valve block (1) and when assembled forms a sheet over all the electro-magnets (2,2′).

Abstract: A solenoid operated hydraulic valve for electro-hydraulic controlled underground mining installations such as advancing support frame controllers, with an actuator housing holding coil bodies, an armature, a magnetizable core, and an operating pin of at least two solenoids. The head end for the operating pins of each solenoid has a cut-out for an operating stroke adjuster. A head plate removable from the actuator housing is provided with a manual operating device for each operating pin and is fastened to the head end of the actuator housing with a head seal between them, a removable valve block accepting the hydraulic multi-way valves and an interposed base seal fastened to the actuator housing base. A housing having a socket connects to an intrinsically safe current supply and accepts the operating electronics for the solenoids, and is located on the side of the actuator housing. In each head end cut-out, an electronic protective circuit for the associated coil body is arranged.

Abstract: A pilot control valve for mining hydraulics. The valve has an insert constructed as a valve cartridge, whose single or multipart valve housing has an input entry for pressure fluid, a connection opening for a load connection, an output opening, opening into the return flow and an axial boring to accept a valve closing body provided with a closing surface, liftable from a valve sealing seat arranged between the entry opening and the connection opening by an electromagnetic or piezoelectric switching device fastenable onto the valve housing. A singe part valve closing body is provided, having a collar shaped sealing surface and the moving part of the closing mechanism in the form of a shaft section, whereby the shaft section enters into a boring section of the axial boring during the lifting movement, closing a radial opening.

Abstract: In an electrohydraulic control device especially for use in the hydraulic systems of advancing support frames of underground mining equipment a valve or valve block 1 is provided with accepting borings 2 and connection borings 27, 28 for load connections (6, 7), which lie on one axis M and merge directly into each other. The accepting space formed by the accepting borings 2 is constructed similarly for all the directional control valves, put together from a pilot control valve 4 and a main control valve 3. In the valve block 1 additionally to the high pressure line P and the return flow line T there runs a control pressure line PST, with which the pressure medium supply for switching the main control valve 3 is effected. The construction according to the invention of the valve block reduces manufacturing costs and offers substantial advantages in the assembly of the directional control valves.