Patent GB-856124-A (GB)
Title: Plastic material calendering machine
IPC: B29B7/56
Filed: 1959-05-12
Abstract: 856,124. Calendering machines. BLAW-KNOX CO. May 12, 1959 [June 5, 1958], No. 16215/59. Class 87(2). Apparatus for milling and calendering plastic stock comprises a pair of rotatable mill rollers, a carriage arranged above the calendering roller and cutting and deflecting means carried by the carriage and adapted to bear against the calendering roller in order to cut and deflect strips of stock for repeated passage between the rollers, the deflecting means being angularly adjustable on the carriage. The nip between the rollers 21, 22, which are hollow for the passage of temperature regulating fluid, is adjustable by a screw 28, a cushion spring 29 being interposed and a shear pin 28d inserted to prevent injury in case foreign matter enters the nip. A band 37 passes round part of the calendering roller 22, driven at a lineal speed equal to the peripheral speed of the roller, and prevents the pellets of material from initially dropping off the roller. The frame 35 carrying the rollers which guide the band is mounted on wheels 47 which run on tracks 48 for ease of removal. Fragments of stock are removed from the feed roller 21 by a nylon scraper blade 53 on a swinging frame 54 which is moved to and from the roller surface by pneumatic cylinders 58. The deflector blades, which are also of nylon, are supported from shafts 68, 70 which form part of a carriage 60 and are clamped down by clamps 75. The shafts 68, 70 connect side members 67 which extend from blocks 66 pivoting on a shaft 65. The carriage is pivotally mounted so that it may be raised by a hoist cable 88, Fig. 5, wound on a drum 80 and lead round a system of pulleys 89, 91 (not shown, coaxial with 92), 93, 92 and 94, the drum 80 being operated by a hand wheel 85 or a motor The pellets are fed to the nip between the rollers from a hopper 100 pivotally supported between two arms 128 clamped to the shaft 70. When the material passes outwards to both ends of the rollers the hopper is on the centre line, as shown ; if in one direction only the hopper is at one end. The feed roller 21 is chamfered accordingly. The feed is adjustable by altering the passage from the hopper by nuts 106 on tie rods 105, Fig. 10, and by altering the positions of swinging extensions 110 from the side plates by a screw threaded shaft 112 rotated by a chain 118 from a sprocket 119, on the shaft 65, by a hand wheel 120. The material is confined to the nip by nylon side boards 123, 126. When the material has passed once around the roller 22 it is diverted to pass outside the side boards by divergent blades 140, of nylon, spring-mounted on an arm 145 which is clamped to the shaft 68. Screw threaded plugs 147 adjust the pressure of the blades on the roller surface and their alignment is adjustable by the position of the clamp 151. The material is repeatedly severed and moved towards the ends of the rollers by nylon deflector blades 155, Fig. 14, spring-mounted on link arms 160 clamped at both ends to the shafts 68, 70 through slotted connections which allow angular adjustment of the blades, with respect to the rollers, by moving the clamps along the shafts. The number of deflector blades may be varied Fig. 2 showing, on the right-hand side, eleven angular deflector blades and an end transverse deflector blade and, on the left-hand side, five angular deflector blades and an end transverse deflector blade. The leading edge of each blade 155 is sharpened as shown at 155b, Fig. 14, and the spring mounting is through floating shafts 159 extending from a bracket 157 to which the blade is bolted. The spring tension is adjustable by plugs 162. The tips of end deflector blades have extensions which conform to the contour of the nip between the rollers, to retain the material, and are connected to the main blade through links to enable them to pivot when the carriage 60 swings as it is raised. When the material reaches the end of the rollers 22 it is cut off as a strip, by a nylon blade on a pivoting frame kept against the surface roller by pneumatic cylinder and piston means, and the strip is continuously fed to a conveyer.