US3241323A

US3241323A - Mine prop assembly

Info

Publication number: US3241323A
Application number: US130732A
Authority: US
Inventors: Grisebach Hans-Theodor
Original assignee: Gewerkschaft Eisenhutte Westfalia GmbH
Current assignee: Gewerkschaft Eisenhutte Westfalia GmbH
Priority date: 1960-08-13
Filing date: 1961-08-07
Publication date: 1966-03-22
Anticipated expiration: 1983-03-22
Also published as: DE1147905B; BE607139A; GB984430A

Description

March 2 1966 HANS-THEODOR GRISEBACH 3,241,323

MINE PROP ASSEMBLY Filed Aug. 7, 1961 2 Sheets-Sheet l March 22, 1966 HANS-THEODOR GRISEBACH MINE PROP ASSEMBLY Filed Aug. '7 1961 2 Sheets-Sheet 2 Fig.3

WIIIIIIIIIIII United States 3,241,323 MINE PROP ASSEMBLY Hans-Theodor Grisebach, Lunen-Galmen, Germany, assignor to Gewerkschaft Eisenhiitte Westfalia, Wethmar, near Lumen, Westphalia, Germany Fiied Aug. 7, 1961, Ser. No. 1l3,732 Claims priority, application Germany, Aug. l3, 1969, G 3%,281 11 Claims. (Ci. 61-45) This invention relates to mining apparatus and more particularly to a device for use in supporting mine roofs.

The system of mining in which this invention is particularly useful is employed in extracting coal underground or any similar material which lies in seams. To extract the coal, the face of the seam is exposed on a long wall. Usually in a relatively low room, a cutter travels along the face of the seam plowing the coal from the face onto a conveyor. The roof of the room behind the cutter and conveyor is supported by props arranged in a gang of units, each unit generally consisting of two pairs of columns or props which are hydraulically extended to the roof.

The pairs of columns are so arranged that while one supports the roof of the other pair can be moved for ward as the cutting proceeds and then as the one which has been advanced is raised to support the roof the other pair of props are loosened and moved up beside the first.

As such units have been arranged heretofore, loosening of one set of props from the roof has often had the effect of permitting the roof to sag, thereby causing cracks leading to obvious difiiculties. In some cases where the columns have been equally spaced the attempt has been made to correct this condition by enlarging the size of the caps contacting the roof. This has not been successful in many cases because the roof surface is not often even to provide good bearing surface. Furthermore, when the caps cover a large area, it is difficult to lower them to move them forward. Sometimes the caps have been provided with interlocking parts so that they slide on one another. Such an arrangement is very awkward as will be understood since the footing for the columns must move along with the caps, and the pair of columns must be kept parallel. Furthermore, if the columns are flexibly mounted with respect to each other the problem of guiding them while they are being advanced is diflicult.

A better arrangement is to provide smaller bearing surfaces for the columns at the roof which make better contact with the roof than wide caps, and in accordance with this invention the caps are made relatively small and they are placed close together so that when one is moved the other which lay beside it holds up the roof. On account of the unevenness of the floor which has a tendency to tilt the columns out of position, special provision is made to assure that the caps will stay in position close to each other after both have been advanced; The invention provides guide means which will enable the columns to pass one another without turning out of position. It will be seen that as one set of columns is being advanced the columns which were adjacent will support substantially the same area of roof and thus it is not necessary that the distance advanced be large. Ordinarily it will not be greater than about half the distance between the fore and aft columns.

A further feature of the invention is the use of guides for the caps which guides them not only vertically but horizontally and in combination with the resilient mounting they maintain the adjacent caps substantially in contact with each other and tend in some cases to tilt the columns toward each other at the top. Thus, pieces of ice rock from the roof will not get caught between the caps.

Another feature of the invention is the flexibility of the footing which accommodates itself to unevennesses of the [loor while maintaining parallelism.

It is accordingly an object of the invention to provide a prop unit of the type described which is adapted to adequately support the roof of the workings, simple to operate and easy to manufacture.

Other objects and advantages of the invention will be in part obvious and in part pointed out hereinafter.

In the drawing in which two embodiments of the invention are shown,

FIG. 1 is a side view of a mine prop constructed in accordance with the practice of the invention and showing a plurality of units in gang arrangement;

FIG. 2 is a plan section taken along the line 2-2 of FIG. 1;

FIG. 3 is a front view of a modified form of prop unit partly in section along the line 3-3 of FIG. 4; and

FIG. 4 is a horizontal section along the line 44 of FIG. 3.

Referring to the drawing and particularly to FIG. 1 and FIG. 2, there are illustrated a complete unit and parts of two others arranged in side by side gang formation, the complete unit being shown at the center. A unit in this embodiment consists of a set of footings 1t and 12 arranged parallel to each other. Each footing is provided with a pair of prop means or columns, collum 14 being at one end of footing 10 and column 16 being spaced from column 14 and at the. other end of footing 10. Likewise on footing 12 is mounted a forward column 18 and a rearward column 20. Each column is tiltably mounted on its footing and is extensible, being hydraulically operated preferably, and has a cap at its top. Thus column 16 has a cap 22 together with column 14 and column 13 has a cap 24 together with column 20 in the usual way, which caps are pressed against the roof of the working 26 to support it temporarily.

Footings

10 and 12 are adapted to slide along the fioor with respect to one another and to be maintained in parallelism and for this purpose there is provided a hydraulic cylinder 28 having a piston rod 30. Hydraulic cylinder 28 is joined by resilient straps or flat spring members 32 to footing 12, and piston rod 30 is likewise joined to footing 19 by resilient straps or flat spring members 34. Being wide and flat, resilient straps or

spring members

32 and 34 allow no lateral movement but are flexible vertically so that as

footings

10 and 12 move with respect to each other they can conform to unevennesses of the floor both in an endwise direction and transversely.

To compensate for any transverse tilting of footings it and 12,

columns

16 and 18 are provided with springs 36 attached to the footings and pressing against the columns so that the

caps

22 and 24 tend to bear against adjacent caps for purposes explained hereinafter.

Advancing of the column is accomplished in a sort of walking motion, the power therefor being supplied by hydraulic cylinder 28 and the piston rod 30. Thus when it is desired to advance

columns

14 and 16, the caps of these columns are lowered by the telescoping action of columns 14 and lo, and footing 10 is stepped forward by hydraulic pressure applied to piston rod 30. After being stepped forward a suitable distance,

column

14 and 16 are extended so that then caps contact roof 26, whereupon similar actuation of

columns

18 and 20 and power applied to hydraulic cylinder 28 and piston 30 stepsfooting l2 forward. Because of the flexibility of

members

32 and 34, footings 1t) and 12 accommodate themselves to the floor surface.

As has been indicated above the unit described is adapted to be used in combination with similar units as indicated. Thus an additional unit shown at the right (FIG. 1) is provided with columns 16 and 14- and the footing 1d and an additional unit shown at the left in part is provided with a footing l2 and columns 18 and 20'. Column 18' has a cap 24' to contact roof 26 and column 16' has a cap 22' also adapted to engage roof 26. Actually, the footing 12 from the spaced apar footing set 10, 12 forms a footing pair 12, lid with the correspondingly adjacent footing til for joint or separate partial support of the mine roof, while the footing 19 from set 10, 12 forms an analogous footing pair 1 12 with the correspondingly adjacent footing 1.2.

In the gang arrangement indicated in FIG. 1 and FIG. 2 the units are arranged to slide in parallelism with respect to each other and for this purpose the adjacent footings in a respective footing pair are provided with a tongue and groove coupling which compels them to move horizontally in parallelism while permitting a degree of flexibility in vertical direction. Thus, in the footing pair l2, l, footing 12 is provided with a longitudinal slot member 38, in which is adapted to slide the tongue 4th of footing Likewise, in the footing pair 12', til, the tongue 42 provided on footing 12 engages the slot member 44 provided on footing it inasmuch as the springs 36 tend to push the various columns away from the center of the set and therefore push the adjacent columns in a footing pair toward each other the caps at the tops of the columns Will be forced against one another and thus press against adjacent areas of the roof 26.

Means is provided to prevent interference of the caps as they pass by each other and to assure that they will assume suitable positions against the roof 26 when they have been stepped forward. Such means is adapted not only to guide the caps into their uppermost positions but in their retracted positions as well. For this purpose each cap is provided with a plate 46 extending downwardly and longitudinally and which are adapted to contact each other at all times on adjacent cap-s. Thus when column 16 is retracted its plate 46 slides downwardly with respecet to the plate 46 on column 18' and in that position as the column is stepped forward it will assume a suitable position for reextension of column 116 so that when column 13 is again advanced the interaction of plates 46 guide cap 24' into a position such as is shown in FIG. 1 where

caps

22 and 24 are adjacent and mutually support substantially the same area of roof.

In FIG. 3 and FIG. 4 is illustrated a prop unit which may be used independently, that is to say, unguided by other units although such other units will be usable in conjunction therewith. In this embodiment piston rod 54 is carried by footing and the hydraulic cylinder 56 is attached to footing 52 by the spring plate 58.

Footings

50 and 52 form a footing pair and the footings are adapted to slide with respect to each other and in contact with each other. Footing 52 flexibly supports a pair of prop means or columns as and 62 adjacent to the pair of columns 6 and 66 likewise flexibly supported on footing 52 and adjacent to columns as and 62, respectively. Each

column

60 and 62 is provided with a cap 68 contiguous to caps 70 supported by

columns

64 and 66.

For the purpose of guiding caps 68 and '70 with respect to each other plates 72 and '74 are provided on

caps

68 and 70, respectively, and perform the functions of plates 46 of the previously described embodiment.

In this instance parallelism of

footings

56 and 52 is assured by their being maintained throughout their length in contact with each other by the flexible plate 58. On account of flexibility of this plate footings 5t) and 52 are able to move sufficiently vertically and otherwise to conform to the irregularities of the floor. Footings and 52 are inclined toward each other so that

caps

68 and 70 remain in contact by means of offset feet 76 and 78 i attached to the footings 5i and 52, respectively, and offset therefrom. A relief spring 84 is provided on each foot 76 hearing against

columns

60 and 62 to resiliently press them into contact at their caps 68 with caps 75 of columns as and 66.

In this embodiment the caps of each unit are adjacent so that the unit may be used independently of other units or in conjunction therewith. Otherwise the function of the

guide plates

72 and 74 has the same effect as the guide plates 46 of the embodiment of FIG. 1 and FIG. 2 wherein the adjacent columns belong to separate prop units.

Thus by the above construction are accomplished among others the objects hereinbefore referred to.

I claim:

1. Mining prop arrangement which comprises a pair of laterally adjacent footings, at least one prop means mounted substantially vertically on each footing adjacent a corresponding prop means on the other footing, each particular footing and said at least one prop means mounted thereon forming a respective prop assembly, advancing means cooperative with said footings and connected to at least one said prop assembly to advance said footings longitudinally with respect to each other, and biasing means connected to at least one said prop assembly and arranged for normally urging the upper end portion of one said prop means on one footing into slidably guiding abutment with the upper end portion of the other correspondingly adjacent prop means on the other footing.

2. Arrangement according to claim 1 wherein said prop means are hydraulically extensible, said footings being longitudinally slidably interconnected by slot guiding means on each footing longitudinally and vertically displaceably cooperating with one another for permitting vertical and longitudinal movement between said footings while preventing transverse movement therebetween, said biasing means including spring means interposed between the lower end portions of said prop means and the respective footing therefor laterally remote from said slot guiding means, and said upper portions being each provided with a plate means thereof having a lateral sliding surface adjacent and facing the corresponding sliding surface of the other upper end portion for maintaining sliding abutment thereat between the correspondingly adjacent prop means under the urging of said spring means.

3. Arrangement according to claim 1 wherein said prop means are hydraulicaly extensible, said footings being longitudinally slidably interconnected by mounted common piston-cylinder means, said piston-cylinder means having vertically flexible connecting means vertically flexible interconnecting said piston-cylinder means to one of said footings for advancing said footings longitudinally with respect to each other while permitting vertical flexible movement between said footings yet preventing transverse movement therebetween, said footings being provided with offset feet laterally outwardly thereof positioned for normally urging the correspondingly adjacent upper end portions of said prop means toward one another, said biasing means including spring means loaded between the lower end portion of one of said prop means and a corresponding offset foot, thereat for normally urging the upper end portion of said prop means toward the upper end portion of the other correspondingly adjacent prop means, and said upper end portions being each provided with a plate means thereon having a lateral sliding surface adjacent and facing the corresponding sliding surface of the other upper end portion for maintaining sliding abutment thereat between the correspondingly adjacent prop means under the urging of said spring means and said offset feet.

4. Mining prop arrangement which comprises a plurality of footing sets utilized in gang formation, each set having two spaced footings, at least one extensible prop means mounted substantially vertically on each spaced apart footing adjacent a corresponding prop means on the laterally adjacent footing of the next set whereby to form thereat a pair of correspondingly adjacent footings with correspondingly adjacent prop means, advancing means cooperative with said footings to advance the spaced apart footings of each set longitudinally with respect to each other and longitudinally with respect to the correspondingly adjacent footing of the respective footing pair, and biasing means arranged for normally urging the upper end portion of the prop means on each spaced apart footing into slidable guiding abutment with the upper end portion of the corresponding prop means on the adjacent footing of the next set, which adjacent footing forms therewith a footing pair,

5. Arrangement according to claim 4 wherein said prop means are hydraulically extensible, said advancing means including a common piston-cylinder means having vertically flexible interconnecting means vertically flexibly interconnecting the spaced apart footings of each set for advancing said footings longitudinally with respect to each other while permitting vertical flexible movement between said footings of each set yet preventing transverse movement therebetween, the spaced apart footings of each set being respectively longitudinally slidably interconnected by separate slot guiding means on each footing longitudinally and vertically displaceably cooperating with a separate slot guiding means on the correspondingly adjacent footing of the next set, which adjacent footing forms therewith a footing pair respectively, for permitting vertical and longitudinal movement between the correspondingly adjacent footings of said pairs respectively while preventing transverse movement therebetween, said biasing means including spring means operatively interposed between the lower end portions of said prop means and the respective footings therefor in each set laterally adjacent said common piston-cylinder means, and said upper end portions being each provided with plate means thereon having a lateral sliding surface adjacent and facing the corresponding sliding surface of the upper end portion of the prop means on the adjacent footing of the next set, which adjacent footing forms therewith a footing pair, for maintaining sliding abutment thereat between such correspondingly adjacent prop means in each pair under the urging of said spring means.

6. Mine prop arrangement adapted to be utilized in gang formation which comprises a pair of laterally adjacent footings, a pair of extensible prop means mounted substantially vertically on each footing respectively adjacent a corresponding pair of extensible prop means on the other footing, each particular footing and the pair of prop means mounted thereon forming a re spective prop assembly, means cooperative with each footing and connected therewith to move said footings longitudinally with respect to each other, and resilient means connected to at least one of said assemblies and arranged to press the tops of the prop means on one of the footings into slidable guiding abutment with the tops of the correspondingly adjacent prop means on the other footing.

7. Arrangement according to claim 6 wherein said means cooperative with each footing include coupling means provided for longitudinal sliding engagement between said footings, said prop means being provided at their tops with substantially vertically extending top guiding means to guide their tops in their vertical movement past the tops of the correspondingly adjacent prop means.

8. Arrangement according to claim 7 wherein said top guiding means include plates affixed to the correspondingly adjacent prop means tops and parallel to each other.

9. Arrangement according to claim 7 wherein said means cooperative with each footing are arranged to move said footings both longitudinally and parallel with respect to each other and include resilient strap vertically flexible to permit tilting of said footings with respect to each other.

10. Arrangement according to claim 9 wherein Iesilient link means are provided which are attached to said footings to pretilt adjacent prop means toward each other, and said coupling means are defined by a slide guide on each footing operatively engaging the slide guide on the adjacent footing and permitting vertical movement between said adjacent footings.

11. Arrangement according to claim 7 wherein said prop means are tiltably mounted on said footings and leaf springs mounted on said footings press adjacent prop means into slidable guide abutment with each other.

References Cited by the Examiner FOREIGN PATENTS 565,918 4/1958 Belgium. (corresponding English language, British Patent 885,645)

1,164,448 5/1958 France. (corresponding English language, British Patent 850,170)

810,296 3/ 1959 Great Britain. 831,275 3/1960 Great Britain.

OTHER REFERENCES Wiemann, German printed application No. 1,090,159, October 1960.

CHARLES E. OCONNELL, Primary Examiner.

JACOB L. NACKENOFF, JACOB SHAPIRO, EARL J.

WITMER, Examiners.

Claims

1. MINING PROP ARRANGEMENT WHICH COMPRISES A PAIR OF LATERALLY ADJACENT FOOTINGS, AT LEAST ONE PROP MEANS MOUNTED SUBSTANTIALLY VERTICALLY ON EACH FOOTING ADJACENT A CORRESPONDING PROP MEANS ON THE OTHER FOOTING, EACH PARTICULR FOOTING AND SAID AT LEAST ONE PROP MEANS MOUNTED THEREON FORMING A RESPECTIVE PROP ASSEMBLY, ADVANCING MEANS COOPERATIVE WITH SAID FOOTINGS AND CONNECTED TO AT LEAST ONE SAID PROP ASSEMBLY TO ADVANCE SAID FOOTINGS LONGITUDINALLY WITH RESPECT TO EACH OTHER, SAID BIASING MEANS CONNECTED TO AT LEAST ONE SAID PROP ASSEMBLY AND ARRANGED FOR NORMALLY URGING THE UPPER END PORTION OF ONE SAID PROP MEANS ON ONE FOOTING INTO SLIDABLY GUIDING ABUTMENT WITH THE UPPER END PORTION OF THE OTHER CORRESPONDING ADJACENT PROP MEANS ON THE OTHER FOOTING.