| 摘要 |
1,119,199. Moulding machines; feeding plastics materials. PROCESS DEVELOPMENTS Ltd. 20 June, 1966, No. 27457/66. Heading B5A. In a device for feeding additives such as stabilizers, colouring or anti-static materials to thermoplastics processing machinery, e.g. extrusion, injection or blow moulding machines, a strand 24 of the material is fed between a knurled capstan 15 driven by motor 14 and a roller 19, through a position-adjustable guide tube 25 and thence to co-operating knives 2 and 6 which slice the strand into pieces of required size. These pieces travel to the processing machine via a funnel (52), Figs. 1 and 2 (not shown), and may be led either through the hopper which contains the bulk of the material to be processed or directly to an inlet in the machine barrel or cylinder. Knife 2 may be one of a number attached to rotary cutter 1 and a number of anvils, 5, only one shown, each of which support a knife 6, may be provided together with associated feed mechanism 15, 19 secured around a circular base-plate 7. The clearance between knives 2 and 6, e.g. 0À004 inch, is adjustable by rotation of an eccentric sleeve 12 whose end projects through a slot 13 in anvil 5. Guide tube 25 is biased by a spring 28 attached to the anvil against the end of an adjustable screw (33), Figs. 1 and 2 (not shown). When several anvils are used it is preferred to guide each strand 24 to a different point along the vertically disposed length of knife 6. Fig. 7 (not reproduced), shows the mounting of blade 6 which is held within a slot by a grub-screw (40) bearing on a disc-spring (41). Furthermore, a pressure pad (37) may be provided to prevent backlash between anvil 5 and sleeve 12. Figs. 4 and 5 (not reproduced), show an alternative cutter 1 where blades (44) are supported between side-plates (45) biased against pins (48) by springs (50). Instead of strip feed by capstan 15, feeding may be accomplished by means of a reciprocating chuck. A visual or audio alarm may be actuated when there is no strand between capstan 15 and roller 19 by consequent movement of motor 14, pivoted at 21, against a microswitch 53. |
