| 摘要 |
925,353. Mine arches. MARGOT VON LINSINGEN, [trading as BOCHUMER EISENHUTTE HEINTZMANN & CO.]. Aug. 14, 1959 [Aug. 16, 1958], No. 27897/59. Class 20 (2). An arched mine support comprises trough sections 1 and 2 overlapping and clamped together by plates 11 and 12. Each section comprises flanges 5, a base 7, and webs 6a, 6b. The surfaces of the webs may be formed as mutually inclined plane faces. In Fig. 5, the distance a is greater than the width of the base but is less than half h. The base 7 may be strengthened by a further web or webs 9 between the webs 6b. The contact between the sections 1 and 2 can be through the web edges 8, the webs 6, or the flanges 5. |
