GB729036A - Improvements in and relating to extrusion machines - Google Patents

Abstract

729,036. Extruding socketed clay pipes &c. GARFORD BENNETT, Ltd. July 4, 1952 [July 5, 1951], No. 15924/51. Class 87 (2). An extrusion machine for e.g. clay pipes having a movable die-component 19 adapted to be locked to the extrusion nozzle 18 is provided with means for automatically stopping extrusion whilst the die is still locked and thereafter unlocking the movable die-portion 19 and restarting extrusion. The machine, except for the above feature, is similar to that described in Specification 653,392. A screw driven through a clutch forces clay into the die 18, 19 and against a ring 30 forming the bottom of the die. When the die is full the ring 30 trips an electric switch 27 which disengages the clutch and stops extrusion. In the modification of Fig. 3 clay extrudes through a hole 33 when the die is full and bears on a hinged flap 34 which operates the switch 27. The switch may be placed in the electrical time-delay circuit of the machine of Specification 653,392 and may act to automatically terminate this delay when the die is full The machine may incorporate a hand operated changeover switch whereby the switch 27 may be substituted for the time-delay circuit of the prior Specification or may be incorporated in the delay circuit as described. After extrusion has been stopped cams are brought into operation which by means of levers and cables unlock the die, re-start extrusion &c. as in the prior Specification. In a modification, Fig. 1 (not shown), a series of cams on a common shaft operate hydraulic or pneumatic valves which control the various parts of the press or the slave cylinders associated with these parts. The cutting mechanism may be as described in Specification 729,050. The machine may be used for extruding a bent pipe by pulling the pipe into an arc as it is extruded. The machine may be horizontal or vertical.