Applying consistent coating to substrate - cleaning the substrate in front of the coating head by using spring-loaded block with doctoring edge set at acute angle

摘要

Appts. for applying a consistent coating on to a material has a nozzle to discharge the coating substance (as a bead) on to a web of material which is moved relative to the coater, and has also a device which mechanically cleans the material before it is coated. This device is a doctor type of arrangement which has a wiping edge applied to the material under spring pressure. The device pref. has a nitrile rubber block. For applying e.g. a consistent adhesive or sealant on to a material (2) the appts. has the coating nozzle (3) and the cleaning device (4). The coater (3) applies its substance along the material (2) by its movement (4), before which the material (2) is cleaned (4). The cleaning device (4) has basically a block (7) to serve as a doctor as its edge (8) is pressed against the material (2) by a spring. The angle made by that edge (8) to the web (2) is between 2 and 5 degs. This also sharpens the edge (8) at the same time. The action of the spring (8) enables the device (4) to act on either flat or slightly curving surfaces, its mounting (9) also enables the doctor (7) to be changed quickly even by hand. The arrangement is suitable for robotic application. ADVANTAGE - The appts. is simple but robust.