Vorrichtung zum Auftragen von Fluessigkeit, z. B. Klebstoff

摘要

A liquid or pasty substance, e.g. an adhesive, is continuously or intermittently applied to a support by continuously applying it in a predetermined thickness to the surface of an application roller or the like, substantially completely removing any excess of the coating substance remaining on the roller after the substance has been transferred to the support, by means of a removal device, from which such excess is passed to a storage vessel from which it can be re-fed to the application member. As shown, the feed and removal devices may constitute a single unit 19 which rests on the application roller 18. The feed device comprises a chamber 33, filled with the coating material which emerges through slots 38 as a series of stripes 40 on the roller 18. The removal device is formed by the chamber 34, which excess material 401 enters through a tapered aperture 39. The chambers 33, 34 are connected to a storage vessel 22 by flexible pipes 20, 21 and the pressure generated in the chamber 34 by the rotation of the roller 18, which is driven from a shaft 44, may be sufficient to overcome the hydrostatic pressure of the material in the container 22, and effect circulation. If necessary, pumping devices may be inserted in the pipes 20, 21. As shown in Fig. 8, the bracket 46 carrying the coating device may be capable of being raised while the roller 18 continues to be driven, so that it is freed from coating-material when not in use. As applied to a labelling-machine, Fig. 9, supports 1 are fed in succession by an intermittently-operated suction-drum 3 and are then forwarded by two pairs of carrier tapes 6, which grip their edges. The drum 3 is caused to rotate to feed a further support as a previous one contacts a control element 12. As each support reaches a control element 13, a roller 24 is caused to swing upwardly, pressing the support into contact with the roller 18 to coat the support with adhesive for a length determined by a control-member in the box 16. As the support reaches the control element 14 an air valve is operated, and a label from a stack 28 is gripped by a suction drum 25, which then rotates through 180 degrees. When the leading edge of the support reaches the control element 15, a roller 241 is swung upwardly to press the coated portion of the support against the label.