US2713774A - Supporting frame, especially mine supports - Google Patents

Description

July 26, 1955 v H. F. HEINTZMANN ET AL 2,713,774

SUPPORTING FRAME ESPECIALLY MINE SUPPORTS 3 Sheets-Sheet 1 Filed Aug. 3, 1949 y 1955 H. F. HEINTZMANN ET AL 2,713,774

SUPPORTING FRAME ESPECIALLY MINE SUPPORTS Fi led Aug. 3, 1949 s Sheets-Sheet 2 Jnrenfors:

y 26, 1955 H. F. HEINTZMANN ETAL 2,713,774

SUPPORTING FRAME ESPECIALLY MINE SUPPORTS 3 Sheets-Sheet 3 Fig. is

Fig. 12

Filed Aug. 3, 1949 nited States Patent.

SUPPORTING FRAME, ESPECIALLY MINE SUPPORTS Hans Friedrich Heintzmann and Wilhelm Stuhlmann, Bochum, Germany, assignors to Bochumer Eisenhutte Heintzmann & Co., Bochum, Germany Application August 3, 1949, Serial No. 108,254

Claims priority, application France August 24, 1948 6 Claims. (Cl. 61-45) This invention relates to mine or tunnel supports of the type consisting of metal profiles or frame members of channel-shape cross section. More specifically the invention relates to mine and tunnel extensible supporting beams of the type in which channel shaped steel or metal profile members are provided with flanges.

It is therefore an object of the invention to provide the profile members as identical as to all cross sections and each profile member having an X-axis laterally across the channel and a Y-axis at right angles thereto and being symmetrical with respect to the Y-axis. Such profile members have the advantage that the moments of resistance of the X-axis and the Y-axis approach one another so that such members will not only take up vertical forces or pressures, but also lateral forces as may be encountered in mine supports. It is a further object of the invention to provide the profile members with flanges, web portions and bottom portions and that each flange has a thickness in a direction parallel to the Y-axis greater than the thickness of the bottom part so that when two overlapping ends of the profile members are forced together with one member in the channel of the other, the flanges will contact each other with a small space between the bottom portions. Another object of the invention resides in the web parts of each profile member diverging gradually outwardly from the bottom part to the flange parts with an opening angle of from approximately 15 to 45.

A still further object of the invention resides therein that due to the identical profile members the resistance to torsion is materially increased by having the flanges contact each other. This will result in a great resistance to twisting of the profile members.

A characteristic feature of the invention resides in the moments of resistance of the X-axis and Y-axis not differing from one another by more than 50% as illustrated by the following example. When one assigns WX as the moment of resistance to the Xaxis and WY as the moment of resistance to the Y-axis and assume WX=54, then WY is at the most 81 and the least 36 as the moment of resistance is not more than 50% between the two. The figure 81 as the upper limit for WY is attained in that 50% of 54, namely 27 is to be added to 54. Also WX=54 as the lower limit is diflerentiated from the upper value WY=36 so that limitation of not exceeding 50% of 36 is 18.

Further advantages and features of the invention may be apparent from the following specification when considered in connection with the accompanying drawings.

The drawings show by way of example a plurality of embodiments of the invention, in which:

Fig. l is a side elevation showing a support for mines with arch-like shape and constructed in accordance with the invention,

Fig. 2 is a cross section showing an embodiment of the connection of the overlapping ends of the channellike profiles forming the support,

Fig. 3 is a cross-section through a single profile,

overlap each other.

2,713,774 Patented July 26, 1955 Figs. 4 and 5 are cross sections illustrating the interposing of the profile ends, Fig. 4 showing a mean position and Fig. 5 the end position,

Fig. 6 is a cross section showing flanges provided with curved contacting surfaces,

Fig. 7 is a cross section showing an embodiment in which one flange contacts the other by means of projections,

Fig. 8 is a plan view of Fig. 7,

Fig. 9 is a cross section showing a similar embodiment as shown in Fig. 7, the projections being provided at the lower surface,

Fig. 10 is a plan view of Fig. 9,

Fig. 11 is a cross section showing an embodiment in which a ledge provided on the one flange engages a recess provided on the other flange,

Fig. 12 is a plan view of Fig. 11,

Fig. 13 is a cross section showing a flange similar to Fig. 11, the ledges and recesses being rounded,

Fig. 14 is a plan view of Fig. 13,

Fig. 15 is a cross section showing a further embodiment in which both flanges are provided each with a recess and a ledge on opposite sides, and

Fig. 16 is a plan view of Fig. 15.

Fig. 1 shows an arch-like supporting frame adapted to be used in mines and consisting of three segments s s and s of channel-like steel profiles. These profiles are provided each with a bottom 2, lateral webs 1 and flanges 3 as seen from Figs. 3-16. The mass of material of which the profiles are manufactured is distributed in such a way that the moments of resistance related to the two main axes of inertia arranged rectangularly the one relatively to the other and designated in the drawings by the lines XX and YY respectively, are equal or different at the highest up to i. e. they are assimilated moments.

The opening angle, i. e. the angle included by the two webs 1 is designated with the letter a. The ends of the channel-like profiles are fitted the one into the other, so that both channels open towards the same direction and Within the overlapping region Z the profiles are connected with each other by clamping or guiding means in such a way that although they are held together they may move relatively to each other in the longitudinal direction.

According to Fig. 2 U-shaped bolts 14 are used at the overlapping portions, threaded at their ends and passing other means may be used for that purpose.

through openings in the flanges of channel-like shaped ledges 13. The ledges are fixed to the bolts by nuts attached to the threaded ends of the bolts. Of course also In consequence of the segments s s and s of the supporting frame being slidable, the frame may finally have the shape shown in dot-and-dash lines in Fig. 1 in which the inside cross section of the gangway or tunnel is considerably diminished.

The opening angle included by the webs mounted, according to the invention, to 15-45. Suitably it is between 20 and 38", preferably between 22 and 25. In the embodiment illustrated in the drawing an angle of 22 is chosen. The cross section of all profiles used for the supporting frame is identical.

Fig. 4 shows the position of the ends of the profiles to be placed into each other in a mean position. After being pressed together by the clamping device the ends of the profiles have the position shown in Fig. 5. The flanges 3 are in intimate contact with each other along the entire length of the overlapping reach or portion Z. The height of the flange is from that purpose greater than the thickness of the bottom so that a space remains between the bottom parts. The webs 1 taper from the flange 3 to the bottom part 2 so that in the position shown in Fig. 4 a wedge-like gap V enlarging downwardly arises, which gap closes if the inner profile is pressed into the outer one in the manner shown in Fig. 5. In this position the opposite surfaces of the Webs and the flanges of the profiles are pressed springily against each other while between the bottoms a distance w may remain. The transitions from the webs to the bottoms are rounded with a relatively large radius.

In the embodiment shown in Fig. 6 the outer surfaces 4 of the flanges 3 are convex and the inner surfaces 5 are concave. Therefore, the outer circumference of the flanges of the inner profiles is embraced and guided by the inner surface of the flanges of the outer profiles.

According to Figs. 7 and 8 the flanges 3 are provided with spaced projections or cams 6 at their outer surfaces distributed over the Whole length of the flanges or only over the length of the overlapping places. These cams or projections provided on the one profile serve for supporting the flanges of the other profile. The cams or projections be also provided at the lower i. e. at the inner side of the flanges as shown in Figs. 9 and 10.

According to Figs. 11 and 12 ledges or ridges 7 are provided at the upper side of the flanges engaging corre sponding notches, recesses or channels 8 at the lower side of the respective counter-flange. The ledges 9 and the appertaining notches 10 may have any suitable cross section f. i. of a trapezoid shape (Figs. 11 and 12) or as shown in Figs. 13 and 14 of semi-circular shape.

According to the Figs. 15 and 16 a notch 12 is provided at the upper side of the flange and a ledge or ridge 11 on its lower side. Of course, it is also possible to provide ledges only at one side and to cause these ledges to engage an even surface of the other flange. Further, ledges may be provided at opposite sides of each flange and the flanges may contact each other by means of these ledges. In all these cases the flanges do not touch each other with their entire surface, but only with a portion thereof.

In all embodiments shown in the drawings the height h of the flanges 3 is relatively large compared with their breadth. Preferably the height of the flanges is double as large or larger than the thickness d of the bottom 2 of the profile. Furthermore, the walls of the webs are as thin as possible relatively to the thickness d of the bottom 2 and to the height of the flanges. The sum of the cross sectional areas of the flanges 3 are equal to, or not essentially different from the cross sectional area of the bottom 2. As the opening angle cc is enlarged by narrowing the bottom 2 the latter has a small width relatively to the height h of the profile, but is of considerable thickness compared with the thickness of the webs 1.

The aforesaid measurements; in connection with the large opening angle 0: cause-a very compact shape of the profile, the resistance of which against twisting, spreading, and other deformations being more than twice as high as that of the best known profiles of this kind. In the preferred embodiments of the invention (see Figs. 3-5) a certain increase of the resistence moments in both main axes could be attained. The high but short flanges used in the preferred embodiments of the invention according to Figs. 3-5 have not only the advantage that they increase the resistance of the profiles against spreading and twisting but also diminish the sensibility of the flanges with respect to local overstresses unavoidable in the underground work stations.

The bottom 2 of the profile has suitably a rectangular basic form i. c. it is confined at opposite sides by even and parallel surfaces, but modifications are permissible. It is also most favorable to provide the webs with opposite even confining surfaces.

The embodiments illustrated in the drawings shows a structural unit or supporting frame for mines. The invention may, however, also be used in connection with supports of any other kind. Further, instead of the archlike shape illustrated in the drawings annular or any other shape may be chosen.

What we claim is:

1. A mine support comprising at least two profile members of identical channel-like cross-section, each member having an X-axis laterally across the channel and a Y-axis at right angles thereto and being symmetrical with respect to the Y-axis with the moment of resistance of one axis not exceeding the moment of resistance of the other axis by more than 50%, each profile member having a bottom part, a pair of web parts and a flange part on each web part opposite the bottom part, the ends of the two members being in overlapping engagement with the engaging channel like portions opening in the same direction, the web parts of each profile member diverging gradually outwardly from the bottom part to the flange parts and including an opening angle of from approximately 15 to 45, and each flange having a thickness in a direction parallel with the Y-axis greater than the thickness of the bottom part whereby the bottom parts are spaced at said overlapping portions of the members when under pressure, and means releasably connecting the overlapping ends of the profile members holding the corresponding and adjacent flange surfaces on each side of the U-shape in direct frictional engagement and permitting a longitudinal sliding movement of said profile members relative to each other when under pressure.

2. A mine support according to claim 1, in which the surfaces of each flange part include a convex outer surface and a concave inner surface whereby the convex outer surface of the flange part of one profile member will contact the concave inner surface of the flange part of the other profile member of two adjacent flange parts at the overlapping portions of the members.

3. A mine support according to claim 1, in which the outer surface of each flange part is provided with spaced projections to contact the inner surface of the adjacent flange part at the overlapping portions of the members.

4. A mine support according to claim 1, in which the inner surface of each flange part is provided with spaced projections to contact the outer surface of the adjacent flange part at the overlapping portions of the members.

5. A mine support according to claim 1, in which the outer surface of each flange part is provided with a ridge extending longitudinally thereon and in which the inner surface of each flange part is provided with a channel extending longitudinally therein so that at the overlapping portions of the members the ridge of one flange will extend into the channel of the adjacent flange.

'6. A mine support according to claim 1, in which the outer surface of each flange part is provided with a channel extending longitudinally therein and in which the inner surface of each-flange part is provided with a ridge extending longitudinally thereon so that at the overlapping portions of the members the ridge of one flange will extend into the channel of the adjacent flange.

References Cited in the file of this patent UNITED STATES PATENTS 831,755 Victor et al Sept. 25, 1906 2,062,686 Toussaint Dec. 1, 1936 2,185,916 Groteschel et al Jan. 2, 1940 FOREIGN PATENTS 398,029 Great Britain Sept. 17, 1932 762,500 France Apr. 12, 1934 41,330 Netherlands of 1937 642,288 Germany Mar. 2, 1937 653,527 Germany Nov. 26, 1937 493,036 Great Britain Sept. 30, 1938 683,564 Germany Nov. 9, 1939

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