| 摘要 |
900,316. Mine roof supports. EGGEMANN, W., and CAMPENHAUSEN, E. VON, [trading as SCHWARZ KOMM. - GES., HERMANN]. Dec. 1, 1958 [Dec. 4, 1957; March 18, 1958; April 22, 1958], No. 38596/58. Class 20 (2). A mine roof bar, Fig. 6, has at one end a tongue 30 provided with a pivot pin 32 and a pin 31. The tongue 30 is introduced between the fork end of an adjacent bar 10, the pin 31 sliding on guides 29a on either internal side of the fork until it is behind their surfaces 34 when the pin 32 will be between notches 33 in the ends of the fork. A wedge member 19 is introduced into an aperture 17 opening into the inside of the fork, the pin 31 being received by an inclined slot therein. A wedge 39, Fig. 10, may be inserted behind the member 19 in the aperture 17 having two sharply-inclined surfaces 38a. In a modification, the wedge 39 is placed in a separate slot behind the slot 17 and acts on the member 19 through a sliding block 45 (Fig. 14, not shown). |
