GB2117433A

GB2117433A - Device for the compression of infill material in mines

Info

Publication number: GB2117433A
Application number: GB08234364A
Authority: GB
Inventors: Kurt-Heinz Voss; Hans-Dieter Sielaff
Original assignee: Bergwerksverband GmbH
Current assignee: Bergwerksverband GmbH
Priority date: 1982-03-11
Filing date: 1982-12-02
Publication date: 1983-10-12
Also published as: GB2117433B; DE3215924C1

Abstract

Hydraulic shield lining frames are provided, particularly in conjunction with blast filling with a stowage screen system taking the form of a sliding roof bar. For the compression of dense stowage extending up to the roof and the avoidance of gaps in the backfilling under the roof the sliding roof bars according to the invention are provided with a compression plate 4 constructed to be retractable and extensible over the width of a lining frame. The compression plate 4 may be hydraulically actuated. <IMAGE>

Description

SPECIFICATION Device for the condensation of infill material in mines The invention relates to a drive for condensing the blast filling entering mine workings having hydraulic lining frames, particularly in the roof zone, the lining frames being provided in the longitudinal direction of the coal face with a stowage screening system consisting, for example, of shield elements.

In the mechanized infilling of hollow spaces in mine workings, particularly in pit coal mining for seams of flat and only slightly inclined deposits, the blast filling method is being adopted more and more widely. When the blast filling process is combined with travelling linings the roof in the zone to be filled is supported by resistant roof bars extending towards the rear. The subsidence of the roof in cases of blast filling nevertheless averages 50% of the thickness of the seam being worked. The subsidence mainly consists of the convergence of the roof, the "blast shadow" and the compression of the filling material.

The convergence between a line in the panel and the filling section amounts to about 12-15% ofthe seam thickness. The "blast shadows", i.e., the spaces which cannot be filled by the filling material amount to about 8-10%, and the compression of the material, as a result of the pore volume of the waste material introduced, causes a further subsidence of 25-30%.

The convergence of the roof can hardly be combated at all by the means avaiiable. Mining en gineersendeavour, by dense filling of the hollow space, to avoid at least the said "blast shadows", likewise attempting, by condensing the filling material to reduce the compression likewise.

Devices of this kind for the condensation of the filling material have already been described in Ger.

Pats. 2835171 and 2918194. As these devices described in the said patents nevertheless have little or no effect on the zone situated underneath the roof and difficult of access for the jet of filling material, the aim of the invention is to provide a device by which this zone can be condensed and which will not be subject to the aforementioned "blast shadows" and which will also condense the hollow spaces which had hitherto been left open after the lining had been drawn forward by the rearward extending roof bars.

The invention solves this problem as a result of the fact that the part of the roof bar which extends towards the rear in the direction of the filling is fitted with a compression plate constructed to be retractable and extensible over the width of a lining frame.

Within the framework of the invention it is also found to be particularly advantagous if the compression plate is constructed to be retractable and extensible by means of at least one hydraulically operable cylinder hinged on and guided underneath the roof bar.

It is likewise found to be of particular advantage if, in accordance with a further embodiment of the invention, the compression plate is constructed to be retractable and extensible via a sliding roof bar of a known type of construction hinged to the end nearer the filling.

The technical progress embodied in the invention mainly resides in the fact that the use of a pivotable compression plate extensible into the stowage space makes it possible to prevent, by additional condensation, the "blast shadows" inevitable in the blast stowage process, and to obtain, by means of this compression of the filling in the horizontal direction, an additional condensation of the filling in the vertical direction as well, which likewise reduces the subsidence resulting from the pore volume of the debris introduced.

An example of the invention is shown in the drawings and will be explained below in greater detail. The diagrams are as follows: Figure 1 a partial elevation of the rearward extending roof bar of a lining frame as seen from below, Figure 2 a partial lateral view of the rearward extending part of a roof bar, shown schematically, Figure 3 a partial elevation of the rearward extending roof bar of a lining frame with the sliding roof bar in the extended position, Figure 4 a partial lateral view of the extended sliding roof bar, with a compression plate hinged to the end thereof.

In the example of the invention shown in Figures 1 and 2 the compression plate 4 is hinged to the rearward extending part of the roof bar 1 via two hydraulic cylinders 2 in such a way that it can be moved inwards and outwards. As may be seen from the side view of a roof bar 1 in Figure 2 the compression plate 4 is rigidly connected to the piston 12 of the hydraulic cylinder 2. At the end situated opposite to the compression plate 4 the cylinders 2 are articulated to the roof bar 1 by means of joints 9 in such a way as to be pivotable in the vertical plane. At the filling end of the roof bar 1 the cylinders 2 are mounted in guides 10 provided with spring elements 11.

It may also be seen from the side view in Figure 2 of the compression plate 4 consists of an upper section 5 rigidly connected to the piston 12 and of a lower section 6 connected to the upper plate section 5 via joints 7.

The lower plate section 6 has an extension 8 which via the joints 7 enables it to be pivoted in the direction of the filling. When the piston 12 moves out of the cylinder 2, i.e., when the actual condensing process is performed underneath the roof 3, the lower plate section 6 assumes the position 6' in which its contour is shown in broken lines in the drawing.

The plate 4 thus reaches, in the condensing process, a larger area than in the restoring process, in which the lower plate section 6 is returned to the position shown in Figure 2, after being pivoted inwards on the filling. To ensure that the compression plate 4will be adapted to an uneven an undulating roof 3 the ends of the hydraulic cylinders 2 are mounted in joints 9 so that the cylinders will be pivotable in the vertical plane.

The guide 10 which serves for the cylinders 2 and which is provided at that end of the roof bar 1 which is nearer to the stowage contains spring elements 11 which in each case ensure the contact prressure of the compression plate against the roof 3.

The efficiency of the process of condensation of the filling material by means of the compression plate 4 is improved as a result of the fact that the hydraulic cylinders 2 are actuated hydraulically in accordance with the invention via flutter valves or comparable devices by which pressure surges enable the hollow space in the roof zone to be almost completely filled while the filling material is being condensed.

In the example shown in Figures 3 and 4 the compression plate is articulated to the end of a sliding roof bar which can be moved out in the direction of the filling. The sliding roof bar 13 is constructed so that it can be caused to siide completely into the roof bar 1. A single-part compression plate 4 is articulated to the end of the sliding roof bar 13 via a joint 14. Underneath the sliding roof bar 13 is the hydraulic cylinder 15 which, by the inward or outward movement of the piston 16, is able to pivot the condensing plate 4 outwards by 90 via a connecting support 19 or move the compression plate 4 into the sliding roof bar 13 to a sufficient distance to ensure that the compression plate 4, when resting against it, can be moved into the sliding roof bar 1. The support 19 is mounted, in such a way as to be pivotable in the vertical plane, in a guide element 17 underneath the sliding roof bar 13. The guide element 17 is slidably mounted on both sides in the like guide 18 and connected to the piston 16 of the hydraulic cylinder 15.

In actuating the thrust cylinders for the sliding roof bar 13 it is found to be of advantage to use flutter valves or a similar device in order to obtain additional and more intensive condensation of the filling material in the roof zone.

Claims

1. A device for condensing the blast filling entering mine workings having hydraulic lining frames, particularly in the roof zone, the lining frames being provided in the longitudindal direction of the coal face with a filling screening system consisting, for example, of shield elements, wherein the part of the roof bar which extends towards the rear in the direction of filling is fitted with a compression plate constructed to be retractable and extensible over the width of a lining frame.

2. A device in accordance with Claim 1, wherein the compression plate is constructed to be retractable and extensible by means of at least one hydraulically operable cylinder hinged on and guided underneath the roof bar.

3. A device in accordance with Claim 1, wherein the compression plate is constructed to be retractable and extensible via a sliding roof bar, hinged to the end near the filling.

4. A device in accordance with Claim 1, wherein the compression plate, over the width of a lining frame, consists of two plate sections, the upper section being rigidly connected to at least one hydraulic cylinder, while the lower section of the plate is affixed to the upper section in such a way as to be pivotable in the direction of filling.

5. A device in accordance with Claim 1, wherein the compression plate is hinged to two cylinders each of which is situated under one side of the roof bar.

6. A device in accordance with Claim 5, wherein the cylinders, at the end situated opposite the compression plate, are hinged in such a way as to be pivotable in the vertical plane, underneath the roof bar.

7. A device in accordance with Claim 2, wherein a guide accommodating the cylinder is provided, at the stowage end of the roof bar, with a spring element.

8. A device in accordance with Claim 3, wherein the compression plate, which is constructed in one piece over the width of a lining frame, is constructed in such a way as to be pivotable by means of at least one hydraulically operable cylinder situated underneath the sliding roof bar and by means of a support hinged to the cylinder and to the compression plate, likewise in such a way as to be pivotable in the vertical plane in each case.

9. A device in accordance with Claim 8, wherein the support is hinged into a guide element, in such a way as to be pivotable in the vertical plane, the said element being guided in a two-sided link guide and connected with the hydraulic cylinder.

10. A device in accordance with Claims 1,2 or 3, wherein the hydraulic cylinder and the sliding roof bar can be subjected to pressure surges by flutter valves or comparable means.

11. A device for condensing the blast filling entering mine workings with hydraulic lining frames, substantially as described with reference to the accompanying drawings.