GB834813A - Tube corrugating apparatus and methods - Google Patents

Abstract

834,813. Making corrugated tubes and bellows; stamping. FLEXONICS CORPORATION. June 5, 1956, No. 17381/56. Classes 83 (2) and 83 (4). A method of making corrugated tubing is characterized in that zones of a piece of plain tubing are each in turn formed into a corrugation by first radially deforming the zone into a partial corrugation by means of a distensible member which engages the tubing and which is directly acted upon by fluid under pressure, and then axially collapsing the partial corrugation by means of relatively axially movable die means which engage the opposite sides of the partial corrugation. The apparatus comprises a base 10 having a central pedestal 12 and pairs of side supports 14 and 16 carrying brackets 22 and 24 respectively which lie on the same plane as a platform 18 carried by the central pedestal 12, said platform incorporating the elastic forming member 20. The brackets 22 and 24 carry a pair of slidable die plates 28 and 30 which loosely embrace the tube 26 on the opposite side to the platform 18. The die plates are operated by hydraulic pistons 32 and 34 (Fig. 2). An additional co-operative die plate 40 is carried at the end of a sleeve 42, the lower end of which has a pair of flanges 44 and 46. The die assembly 40-46 is shifted by a pair of hydraulic pistons 48 and 50 secured to the flanges 44 and 46 and spring-loaded guide pins 56 and 58 urge the sleeves towards their lowermost positions. Stop screw 62, 64 limit the upward movement of the die-plate 40. The tubing is intermittently vertically fed by an annular member 66 frictionally mounted on a sleeve 68 on the central pedestal 12, said member 66 having a rubber outer gripping ring 70. An hydraulic piston 82 intermittently raises the sleeve 68 through a one-way ball clutch 74 and rack-and-pinion gearing. An adjustable stop pin 86 limits the feed of the gripping member. In operation, fluid pressure is applied to the forming member 20 to project a shallow corrugation 88 (Fig. 5) on the tubing after which the die plate 40 is raised to collapse and deepen the corrugation in co-operation with the die plates 28-30. During the collapsing operation the forming member 20 is either expanded or collapsed, but during the final forming operation by the die plates the member 20 is in its normal collapsed position (Fig. 7). An hydraulic control circuit (Fig. 8) operates valves controlling the pistons actuating the die plates and feed member in predetermined timed sequence by means of a series of operating cams driven from a motor 134. In a modification, the forming member 20 comprises an annular cylindrical rubber band 20a clamped to the platform 18a by rings 138 and 140 (Fig. 9).