| 摘要 |
1,091,565. Web coating apparatus. W. D. McALPINE. May 5, 1965 [May 5, 1964], No. 19047/65. Divided out of 1,091,564. Heading D1L. In apparatus for coating a material with molten thermoplastic material a roller 38 is mounted for rotation in bearings 39 and is driven from a motor 39a. Thermoplastic material in granular or flake form is fed into a hopper 40 having a curved bottom plate 41 which is spaced from the roller surface but positioned progressively closer thereto so as to define a chamber 80 of progressively decreasing depth from an inlet end 81 to an exit end 82. The front portion of this chamber is heated by heaters 42 and the roller 38 is also heated so as to maintain the thermoplastic material in chamber 80 in a molten state. The rear section of the hopper has cooling means 44, 45, 46 to maintain the thermoplastic material therein in particle form and this prevents oxidisation of the molten material in chamber 80. In use roller 38 picks up molten thermoplastic material from the chamber 80, the material is smoothed by heated doctor blade 48 and applied to web 49 brought into contact with the surface of the roller by suitable guide means. In a second embodiment (Fig. 3, not shown) a second roller 83 is spaced from the first roller 38 and extending between the two rollers is a heat conductive endless belt 85. In this embodiment roller 83 is cooled and the web 49 is brought into contact with the endless belt 85 such that thermoplastic material picked up by the belt 85 is transferred to the web 49. |
