The present invention relates to an apparatus for laying down a pipe line composed of individual pipe sections arranged end-to-end in an open trench.
A known apparatus is described in U.S. Pat. No. 3,994,139. This known apparatus is particularly useful in laying a pipe line in water bearing soil, and employs an advanceable drive shield excavating an open trench and a sealed receptacle for receiving the individual pipe sections. The receptacle is directly coupled to the frame of the drive shield and a series of supplementary elongate planks or members lie between the receptacle and the trench walls. These supplementary planks are pivoted to the cutter planks or drive members of the drive shield. The trench walls are unsupported behind the receptacle however and in certain cases this is a disadvantage since separate shoring sheets or planks may be needed to support the trench walls in the rear zone.
A general object of the present invention is to provide an improved apparatus of the aforementioned kind where the various operations, i.e., the trench driving, the pipe laying and the subsequent re-filling of the trench can be carried out largely independently of one another permitting the overall operation to proceed more rapidly.
USPTO Backgrounds
USPTO Backgrounds