Apparatus for conveying particulate material

• US 4,186,658 A
• Filed: 08/03/1978
• Issued: 02/05/1980
• Est. Priority Date: 01/24/1977
• Status: Expired due to Term

• Current Assignee: Stage Technologies Incorporated
• Original Assignee: Stage Technologies Incorporated
• Inventors: Brown, Douglas B.
• Primary Examiner(s): Feldman, Peter
• Application Number:
  US05/930,677
• Time in Patent Office: 551 Days
• Field of Search: 100/35, 100/37, 100/41, 100/117, 100/144, 100/145, 100/147, 100/148, 100/150, 100/DIG. 3, 100/DIG. 5, 100/DIG. 8, 100/DIG. 9, 100/137-139, 100/191, 100/19 2, 425/204, 425/207, 425/376
• US Class Current: 100/148
• CPC Class Codes: B30B 11/22 Extrusion presses; Dies therefor extruding by the use of roller-and-ring machines B30B11/20
• CPC Class Codes: B30B 11/265 with precompression means

Abstract

Apparatus for conveying particulate material of the type wherein it is desired that the material be simultaneously pre-compacted from a generally loose state to a more or less solid "plug" state. A screw conveyor is arranged to deliver loose particulate material to an intermediate chamber at the end of the screw conveyor means wherein the material is pre-compacted by the action of the screw conveyor. Following the intermediate chamber, a piston reciprocating coaxially with the screw conveyor further urges the material in a direction coaxial with the centerline of the screw conveyor to further advance the material through a straight coaxial conduit within which the material becomes compacted to an increased degree of compactness, solely by the action of the reciprocating piston. The reciprocating piston has preferably an annular face, whose outside diameter is generally the same as that of the I.D. (inside diameter) of the conduit. The second, high degree of compactness is thus achieved solely by the action of the piston. Accordingly, the mounting of the screw conveyor is not subjected to extreme forces. The device is capable of compacting, for instance, fibrous material of a relatively low fibre shear strength to an extremely high compactness without exceeding the fibre shear limit in the area of the screw conveyor. Frictional drag in the conduit following the apparatus may be increased by vanes protruding inside of the conveyor. The depth of the friction increasing vanes may be selectively adjustable.

Claims

1. Apparatus for feeding a mass of material comprised of solid particles, from an outlet of hopper means to a processing means for processing of said material, said apparatus comprising, in combination:

(a) screw conveyor means for advancing said mass in a generally axial direction away from the outlet of said hopper means, towards an inlet of a tubular conduit, the outlet of said conduit being in a permanent communication with said processing means, said conduit extending generally coaxially with said conveyor means;

(b) an intermediate chamber at the discharge end of said conveyor means, said intermediate chamber being generally coaxial with said conveyor means, being located between said conveyor means and said conduit means, and normally being in a communication therewith;

(c) reciprocating piston means having a forward face end disposed at said intermediate chamber for a reciprocating movement generally coaxially with said screw conveyor means, said forward face of said piston means being turned towards said processing means, said piston means being of the type of an annular piston whose outside diameter generally corresponds to the inside diameter of said conduit, the inside diameter of said piston generally corresponding to the outside diameter of said screw conveyor means, the discharge end of said screw conveyor means being telescopically received inside said annular piston, whereby the portion of the interior of said annular piston between the discharge end of the conveyor means and the face of said piston means forms said intermediate chamber;

(d) first drive means for rotating said screw conveyor means and second drive means for reciprocating said piston means;

whereby said conveyor means is arranged to advance said mass to said intermediate chamber means, while further advance of said mass through said conduit is effected solely by compressive action of said face of the piston means.

2. Apparatus as claimed in claim 1, wherein the conduit comprises protrusion ribs extending longitudinally of the inside wall of an axially limited portion of the conduit and gradually increasing in height in the direction towards said processing means.

3. Apparatus as claimed in claim 2, further comprising means for selectively adjusting the height of said protrusion ribs, to thus adjust the frictional force acting on said mass in the area of said protrusion ribs.