Apparatus and method for making a drainage element

An apparatus for making drainage elements, said apparatus comprising

• a hopper disposed about a vertical axis for receiving a supply of loose aggregate, said hopper having an outlet of cylindrical shape on said axis for receiving a collapsed cylinder of mesh material about a lower end thereof;
• a hollow mandrel extending through said hopper and disposed on said axis, said mandrel having a centrally disposed bore for passage of a length of material therethrough and a screw-threaded flight extending about and along an outer periphery thereof;
• and
• means for rotating said mandrel relative to said hopper to effect movement of loose aggregate in said hopper into and through said outlet of said hopper whereby the loose aggregate is pushed through said outlet of said hopper into an annular space between the length of material passing out of said hopper and the elongating cylinder of mesh material secured at one end to and moving with the length of material.

An apparatus for making drainage elements, said apparatus comprising

• a hopper disposed about a vertical axis for receiving a supply of loose aggregate, said hopper having an outlet of cylindrical shape on said axis for passing aggregate therethrough;
• an extension secured to said outlet and having a bulbous cross-sectional shape for receiving a cylinder of mesh material on an upper section thereof;
• a sleeve mounted in said hopper for guiding a length of material therethrough;
• and
• a pair of rollers for driving the length of material through said sleeve, said hopper and said extension while dispensing the aggregate through said outlet of said hopper and said extension into an annular space between the length of material passing out of said hopper and the elongating cylinder of mesh material secured at one end to and moving with the length of material.

An apparatus for making drainage elements comprising

• a hopper having an outlet disposed on a vertical axis and defining a closed chamber communicating with said outlet;
• at least one pipe for delivering a flow of aggregate into said chamber;
• a first gate selectively movable between an open position allowing passage of aggregate from said pipe into said chamber and a closed position closing said pipe to said chamber to block passage of aggregate into said chamber;
• a second gate in said hopper selectively movable between an open position allowing passage of aggregate from said chamber into said outlet and a closed position closing said chamber to said outlet to block passage of aggregate into said outlet;
• a blower in communication with the interior of said hopper for blowing aggregate in said hopper through said outlet, said blower being selectively operable to blow air into said chamber with said first gate in said closed position thereof and said second gate in said open position thereof.

A method of making a drainage element comprising the steps of

• placing loose aggregate in a hopper having an outlet of cylindrical shape;
• positioning a perforated plastic pipe concentrically in said outlet of said hopper;
• placing a collapsed cylinder of mesh material on and about a lower end of said outlet of said hopper;
• securing one end of said cylinder of mesh material to said perforated plastic pipe;
• and
• dispensing the aggregate in said hopper through said outlet of said hopper into an annular space between the pipe passing out of said hopper and the elongating cylinder of mesh material secured at one end to and moving with the pipe.