| 摘要 |
1,119,166. Connections between mine roof support bars. GUTEHOFFNUNGSHUTTE STERKRADE A.G. 9 Dec., 1965 [22 Dec., 1964], No. 52206/65. Heading E1E. A box-section roof support cap 1 is provided at one end with a pin, see Fig. 1 (not shown), and at the other end with an eye portion 3 having an end plug 8 which is secured to the cap 1 by a pin 9 allowing relative movement in a horizontal plane. The eye portion 3 has a part-circular tapering recess 6 to receive the pin portion of an adjacent roof cap which is secured thereto by a wedge. |
