| 摘要 |
1,149,423. Programmed-extruders. L. D. CARLO. 5 Oct., 1966 [21 Oct., 1965], No. 44449/66. Heading B5A. [Also in Divisions F2 and G1] An axially profiled extrudate B is made by forcing material C by means of a ram 40 past a mandrel-supporting spider 30 and through orifice device 12 comprising blades 50, Fig. 3, operable in the manner of an iris-diaphragm to vary the diameter of the extrudate, and remotely controlled by a programmer 162, Fig. 1, to produce a preselected profile. Blades 50 each pivot on a pin 62 and move when a camplate 82 is rotated by the co-operation between further pins 64 on the blades with slots 84 in the plate. A motor 126, Fig. 1, controlled from programmer 162 via voltage lines 128, 130, rotates cam-plate 82 through gears 122, 120, 110 and 96. A cam 160 on ram 40 actuates limit switches 156, 158 for a sensing mechanism 150, and axial movement of the ram, and hence the amount of material extruded, is communicated to mechanism 150 through rotation of a pinion 142 by rack 140. This information is then passed to programmer 162 to be correlated with punch card or the like profile information 166, 168. Pinion 142 may be replaced by a slide 180 moved by extrudate B, and which contacts a rheostat 176 connected to programmer 162 via line 184. In an alternative arrangement, Fig. 8 (not shown), motor 126 is adjusted by co-operation between a cam (230), having a surface (232) representing the desired profile, and a cam follower (236). Blades 50 of orifice device 12 are described in detail, Fig. 4 (not shown), together with an alternative, more rigid, blade (50a), Fig. 5 (not shown), and an iris-diaphragm utilizing radially reciprocable rectangular blades (254), Fig. 9 (not shown). The profiled extrudate B may be of thermoplastic or thermosetting plastics material and in particular thermosetting plastics containing metal particles, e.g. epoxy resin and steel particles, with extrudate B being cut and cured to form a profiled blank which only requires final grinding to form a roll. As shown, Fig. 7 (not reproduced), the blank has been cropped to give square edges (202, 204), is supported by expandable mandrels (214, 216), and is acted upon by grinding wheel (220). |
