A machine for the dry digging of deep ditches, in sliding, crumbly and loose earths, without causing landslips in the walls

摘要

914,032. Earth - excavating apparatus. DOMENIGHETTI, C. Jan. 6, 1959 [Sept. 13, 1958], No. 457/59. Class 68 (1). In a machine for the dry digging of deep ditches in sliding, crumbly or loose earth necessitating backing up of the side walls of the so formed ditch means are provided for varying the distance between the leading edges of plates 17 for backing up the side walls and a digging unit 1 so that localised controlled cavitation can occur in the vicinity of the leading edges, said cavitation facilitating the advance of the plates. The referred to means may be screw units or pneumatic or hydraulic rams.