Method and appliance for laying a sheet of material in the ground

• US 4,720,212 A
• Filed: 02/13/1986
• Issued: 01/19/1988
• Est. Priority Date: 02/14/1985
• Status: Expired due to Fees

• Current Assignee: Digging Trading Company NV
• Original Assignee: Digging Trading Company NV
• Inventors: Hofman, Arie A., Steenbergen, Bastiaan G.
• Primary Examiner(s): NOT, DEFINED
• Application Number:
  US06/828,998
• Time in Patent Office: 705 Days
• Field of Search: 405/36, 405/38, 405/50, 405/52, 405/156, 405/157, 405/174, 405/176, 405/177, 405/179, 405/180, 405/183, 405/267, 405/270, 405/107, 405/109, 47/9, 47/56, 111/1, 111/2, 111/3, 111/7
• US Class Current: 405/176
• CPC Class Codes: E02D 19/18 by making use of sealing aprons, e.g. diaphragms made from bituminous or clay materialconcrete diaphragms E02D5/18; sealing or joints for hydraulic engineering work E02B3/16
• CPC Class Codes: E02F 5/06 with digging elements mounted on an endless chain E02F5/109 takes precedence; with digging elements mounted on an endless chain per se E02F3/08
• CPC Class Codes: E02F 5/101 forming during digging, e.g. underground canalisations or conduits, by bending or twisting a strip of pliable material; by extrusion

Abstract

A sheet of material is laid in the ground by digging a trench in the ground by means of a trench digger and unwinding the sheet of material from a stock roll above ground level, passing it into the trench in a downward direction and diverting it in a direction essentially parallel to ground level. In order for the protective housing which is attached downstream of the trench digger and has to keep the trench open over its length not to be designed too long the sheet of material is passed into the trench folded double and is unfolded via three return rollers or rods or flanges, and passed in the unfolded state in an approximately vertical plane in the horizontal direction. To lay the film at a particular depth in an approximately horizontal position or in the shape of an essentially horizontal gutter in the ground the sheet of material is passed, folded double, in a trench in the shape of an inverted T and, via four return rollers or rods or plate edge flanges which are located essentially near the bottom of the trench, is folded open and passed further in a horizontal or gutter-shaped position in the horizontal direction.

Claims

1. Method for laying a sheet of material in the ground, wherein a trench is dug in the ground and the sheet is passed into the trench while being unwound from a stock roll, the sheet of material being fed, with its longitudinal dimension in a downward direction, into the trench from the stock roll located above ground level, and deflection means for turning the longitudinal dimension of the sheet, within the trench, to extend longitudinally in said trench;

the method comprising the steps of introducing the sheet of material into the trench folded on itself along its length, unfolding said sheet into an approximately vertical plane, and extending said sheet along the trench.

2. Apparatus for use in conjunction with a trench digger for the laying of sheet material in a dug trench, a protective housing receivable within and movable along a dug trench for protecting the trench against collapsing of walls of the trench, means located above the protective housing for mounting a longitudinally folded sheet of material for longitudinal introduction of the folded sheet downward into said housing, three elongate sheet unfolding members arranged in a substantially vertical plane within the housing for engagement of the downwardly introduced folded sheet therewith for the unfolding of the sheet into a substantially vertical plane and the directing of the unfolded sheet longitudinally along the trench, two of said sheet unfolding members converging toward a point of convergence in the direction of movement of the protective housing, the third sheet unfolding member, starting from a point near the point of convergence of the first two members, extending between the converging members rearwardly relative to the direction of movement of the housing and essentially parallel to the trench.

3. Apparatus for use in conjunction with a trench digger for the laying of a sheet of material in a dug trench, a protective housing receivable within and movable along a dug trench for protecting the trench against collapsing of walls of the trench, means located above the protective housing for mounting a longitudinally folded sheet of material for longitudinal introduction of the folded sheet downward into said housing, four elongate sheet unfolding members located in generally horizontal spaced relation to each other within the trench for engagement of the downwardly introduced folded sheet therewith, two of said sheet unfolding members converging toward a point of convergence in the direction of movement of the protective housing, the other two sheet unfolding members, starting from points near the point of convergence of the first two members, extending between the converging members rearward relative to the direction of movement of the housing and generally parallel to the trench, said other two sheet unfolding members paralleling each other in closely spaced relation for reception of the folded sheet downward therebetween and laterally thereabout for a generally horizontal unfolding of the sheet toward the first two members and a redirecting of the generally horizontal unfolded sheet, by the first two members, longitudinally along the trench.

4. Apparatus for use in conjunction with a trench digger for the laying of a sheet of material in a dug trench, a protective housing receivable within and movable along a dug trench for protecting the trench against collapsing of walls of the trench, means located above the protective housing for mounting a longitudinally folded sheet of material for longitudinal introduction of the folded sheet downward into said housing, multiple elongate sheet unfolding members within the trench for engagement of the downwardly introduced folded sheet therewith, two of said sheet unfolding members converging toward a point of convergence in the direction of movement of the protective housing, said two converging members defining a plane, the remainder of said sheet unfolding members lying substantially in said plane and, starting from generally the point of convergence of the first two members, extending between the converging members rearward relative to the direction of movement of the housing and generally parallel to the trench for reception of at least a portion of the folded sheet thereabout and a redirecting of the sheet toward at least one of the first two members for a subsequent redirecting longitudinally along the trench.