Abstract: A device for detection and adjustment of the tension of a scraper chain of a chain conveyor, in particular of a face conveyor, having a tensionable return station, on which a spoked chainwheel to reverse the scraper chain, having chain links and scrapers attached thereto, is supported between the bottom race and the top race. The devices including a sensor which determines the tension of the scraper chain at the return station and the sensor having a swivellable sensor body coupled with a shaft encoder. The sensor body being in the top race and in contact with the upper face of the scraper chain in a measurement zone with provision being made in the measuring zone for vertical play for the run of the scrapers and/or the chain links.

Abstract: In the method according to the invention and the arrangement or according to the invention for extracting extraction products in underground mining operations using the caving method, the extraction products (20) collapsing in an upper gate area (10) are extracted via at least one extraction funnel (13) or the like into an extraction path (14) driven below the gate and are transported away therein by means of an extraction conveyor (15). According to the invention the extraction funnels (13) are arranged laterally beside the extraction conveyor (15) and lead at their lower end into a ramp surface (17) inclined towards the extraction conveyor, the extraction products extracted from the gate through the extraction funnels being transported slidingly over the inclined ramp surface to the extraction conveyor.

Abstract: Toggle retainers are disclosed for toggle connection assemblies of conveyor pans of a chain scraper conveyor or guide troughs of a mining machine guide used in underground mining operations. The toggle retainers feature laterally open toggle pockets into which toggles can be readily inserted. The toggles have toggle heads that are connected in one piece with one another, with at least one of the toggle heads having a bolt tongue. A toggle retainer can be affixed to one of the toggle pockets by extending the retainer under one or more wall projections. The toggle retainer is designed so as to have multiple parts, with a bolt element, in the assembled state, extending over the bolt tongue and under the wall projections. To ensure a secure placement of the toggle in the toggle pockets, a filler element can be form-fittingly inserted between the bolt element and the back wall of the toggle pocket and connected to the bolt element via a screw joint.

Abstract: A mining machine for underground mining is disclosed, particularly an extraction or coal plough. When in use, the mining machine is guided along a machine guide, said machine guide including a guide rail and a guide pawl. The guide pawl engaging around said guide rail from above wherein a guide piece is disposed between said guide pawl and said guide rail. The guide piece is releasably attached or attachable to said guide pawl and is sliding along said guide rail. According to the invention, said guide pawl has at least one support means whereassaid guide piece in its installation position is supported on said support means. Further, the guide piece with said guide pawl is fixed by means of a locking mechanism in the longitudinal direction of said guide rail.

Abstract: A bit holder for a ploughing bit, particularly a bottom bit of a coal plough, includes an insert pocket 12 which is open at the top side 11 for receiving and supporting a bit stem of the ploughing bit and which pocket 12 is bounded on its edges by two lateral supporting walls 20, 30, a front supporting wall 13 and a rear supporting wall 14 with the rear supporting wall 14 projecting above the front supporting wall 13. In order to minimise the wear effect on the contact surfaces between bit stem and bit holder, the lateral supporting wall 20 facing away from the working face when the plough is in use projects above the front supporting wall 13 and the other lateral supporting wall 30 and forms an extended lateral support for the bit stem with respect to the other supporting wall 30.

Abstract: Toggles are disclosed for toggle connections of conveyor pans of a chain scraper conveyor or conveyor troughs of a mining machine guide. In providing a toggle and a toggle connection, with which high axial forces can be transmitted while, at the same time, maintaining high angular mobility of the pans and troughs, shoulder areas of the toggle are designed so as to be spherical. Because of the spherical design of the shoulder areas, the vertical mobility of adjoining conveyor pans is improved while at the same time the transmission of axial tensile forces to the toggle heads is optimized.

Abstract: Chain guide arrangement for a mining machine, in particular for an extraction plough. The chain guide arrangement comprises a first chain passage for a load strand and a second chain passage for a return strand of a drive chain of the mining machine. At the end areas of the chain passages there are provided a drive station and a return station for the drive chain. At least at one of the chain passages a chain guide for the load strand and/or for the return strand of the drive chain is provided in a transition area to the drive station/s and/or the return station. According to the invention, the chain guide comprises a retaining pocket being open towards the drive chain and at an end face thereof being bounded by a hinge pin arranged to be transverse to a direction of movement of the chain. The chain guide further comprises a hold-down device comprising a pin seating on at least its one end face which pin seating matches with the hinge pin and is open on one side, and a locking arrangement.

Abstract: The invention relates to a conveyor pan (150) for underground face and gate conveyors, with a bottom run (102) and a top run (103) for the guidance of a scraper of a scraper chain, with a frame work construction (101) which has side walls (110) comprising cast parts firmly joined to each other, with an intermediate flange (111) and an upper moulded flange lug (112) extending outwards from it and a lower moulded flange arm (113) as well as a moulded foot flange (120) extending inwards and bordering the bottom run partly to the side.

Abstract: A lift cylinder arrangement is disclosed for a hydraulic support frame for underground mining. The support frame has a lift cylinder for lifting the base shoes during advancing, which is supported on the one hand on a return rod and on the other hand, in a pivoting manner, with an end supporting head to a drawbar connected to the base shoes. In order to allow a simple, rapid and reliable connection between the supporting head and the drawbar, the supporting head is connected to the drawbar by a plug-type locking system comprising two plug-type locking elements, which include first locking notches on the drawbar, and arranged complementarily thereto second locking notches on the supporting head, whereby the plug-type locking elements engage in at least one of the locking notches with clearance.

Abstract: The invention relates to a method for joining the functional parts of hydraulic or pneumatic operating devices, such as hydraulic props and rams for underground mining, with a first part exhibiting an external wall section and a second part exhibiting an internal wall section, which are joined together with mutually overlapping wall sections and in this region are connected together, as well as the joining connection for corresponding functional parts. In accordance with the invention both wall sections comprise a depression, which in the connected state form a cavity that is filled with a fluid casting compound of plastic, which after its hardening or solidification connects the two parts together by means of a positive form fit.

Abstract: The conveyor pan according to the present invention has a framework construction (1) having the bottom run (2) and an interchangeably constructed exchangeable tray (4) forming the top run (3), which can be lifted out, vertically supported on the framework (1). The framework construction (1) of the conveyor pan (50) has two roiled U-profiles forming the side walls of the conveyor pan, each of which has a vertically extending intermediate arm (11), an upper, outwards facing flange arm (12) and, lower outwards facing flange arm (13). The identically constructed but mirror imaged iron U-profiles (10), i.e.

Abstract: The invention relates to a plough chain strand 50 with horizontal chain links and vertical chain links including normal chain links 30, 40, the chain link legs of which are connected by chain link arcs and engage one another alternately in an intractable manner. In the chain strand 50 in front of and behind the chain connector link 10 is arranged in the same installation position as this at least one special chain link 20, the link legs of which comprise the same outer contour, especially the same width and the same thickness, as the outer legs of the connector link parts of the chain connector link 10. Due to the special chain links 20 preceding and trailing the chain connector link and having the same or a marginally larger contour as this, the wear of the chain connector link 10 of the chain strand 50 according to the invention is reduced or avoided if compared to known plough chains.

Abstract: The present invention relates to a conveyor pan (50) for underground face and gate conveyors, with a bottom pan (2) and a top pan (3) for the guidance of scrapers of a scrapper chain, the conveyor pan (50) having a welded frame construction (1) comprising side walls firmly fixed to one another with a conveyor base (8) and a means (60) of joining the conveyor pans. In accordance with the present invention the side walls comprise mirror image single part rolled profiles (10) with a constant profile form over the length of the conveyor pan (50), whereby the rolled profile (10) includes a base arm (11) and a top arm (12) both angled outwards as well as an extended intermediate arm (13) joining these, which is provided with an offset (14), onto which intermediate arm (13) on its inside at least one step (17) is formed for the support and welding on of at least one of the intermediate plates (40A) stiffening the frame construction (1).

Abstract: A toggle retainer (10) for toggle connections of conveyor pans (5) for chain scraper conveyors, guide troughs of mining machines and similar, with a locking plate (30) engaging across the locking extension (23, 24) on the toggle head (21, 22) of a toggle (20) and securing the toggle (20) in the toggle accepting pocket (9) against falling out to the side, both ends (31, 32) of which can be introduced into an insertion pocket (11, 12) in the toggle acceptor (1) and which for retention in the locking cut-outs (13, 14) of the toggle acceptor (1) have at least one aperture (37) into which the shaft (41) of a locking element (40) engaging in one of the locking cut-outs (13, 14) can be inserted. The locking plate (30) is provided with transverse borings (38, 39), one of which opens into the aperture (37) and in which a securing clamp (50) engagement can be inserted or is inserted retaining the shaft (41) by positive.

Abstract: The extraction machine for underground ore extraction operations, with extraction of the extraction product by blasting has an advancing support equipment (11) and a face conveyor (18) coupled to it as well as at least one boring device (26) for the production of shot holes (23) and a loading device (27) to supply the face conveyor (18) with the blast rock loosened by blasting, whereby the boring device (26) and the loading device (27) are assigned to a common boring and loading machine (24), which can be driven along the face conveyor (18) at right angles to the direction of mining in the direction towards the rock face (20) running parallel to the direction of mining, or away from this.

Abstract: In a toggle bar link (100) for conveyor pans of conveyors or guideway pans of extraction machine guideways, with toggle bar sockets (1) arranged at the sides of the pans in whose socket cut-outs (3) a toggle bar can be inserted and retained by securing elements (4), both the toggle bar (2) and the securing elements (4) as well as the toggle bar sockets (1) are constructed intrinsically symmetrically and the toggle bar sockets (1) are arranged symmetrical to a plane of symmetry (S) running through the joint between the pans. Owing to the symmetrical construction of the individual parts they can not only be produced simply but also no orientation problems are posed in the assembly of the individual parts.

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: The subject matter of the present invention relates to a plow guide for a chain-pulled plow for use in underground mining operations, with plow guide troughs 20 and 50 having multiple parts and being connectable to one another by means of coupling elements so as to be tension-proof and angularly movable. Each plow guide trough has a center piece 21 and 51 with superposed chain guide channels 10C, 10B, 10D, to both sides of which center piece an end piece, 22,23 and 52,53 is joined by welding, which end piece is a single-piece casting with superposed chain channel sections that are separated by a sliding spacer piece that is cast on. To make available a high-performance Gleithobel system with a high tool life, cast-on holding pockets 24,25 and 54, 55—which are open on the working face side—for toggle connections with toggles 1 as coupling organs are disposed on end pieces 22,23 and 52, 53. (FIG.

Abstract: A lift cylinder arrangement is disclosed for a hydraulic support frame for underground mining. The support frame has a lift cylinder for lifting the base shoes during advancing, which is supported on the one hand on a return rod and on the other hand, in a pivoting manner, with an end supporting head to a drawbar connected to the base shoes. In order to allow a simple, rapid and reliable connection between the supporting head and the drawbar, the supporting head is connected to the drawbar by a plug-type locking system comprising two plug-type locking elements, which include first locking notches on the drawbar, and arranged complementarily thereto second locking notches on the supporting head, whereby the plug-type locking elements engage in at least one of the locking notches with clearance.