Patent GB-1053213-A (GB)
IPC: B05B13/00
Abstract: 1,053,213. Coating apparatus. WEYER HAEUSER CO. Jan. 24, 1964 [Jan. 28, 1963], No. 3188/64. Heading B2L. [Also in DivisionD1] A method for controllably applying liquids on moving surfaces comprises establishing a liquid supply available at an adjustable controlled rate of flow, depositing the liquid uniformly on the moving surface, measuring the liquid consumption and distribution by selectively operating sensing, counting, calibrating and indicating devices determining flow rates of the liquids and the moving surfaces, giving an immediate presentation of liquid consumption rate expressible in industry standard terms such as pounds of liquid per one thousand square feet of surface area, and adjusting the liquid consumption rate, by increasing or decreasing, optionally, the controllable rate of flow of the established liquid supply or the speed of the moving surface. In one embodiment (Fig. 3) the adhesive supply consists of a bottom storage tank 64 and a top mixing tank 160. Adhesive is fed from tank 64 by a positive displacement pump 167 through manifolds 170 to outlets 171 for filling the nip or cavity 172 between driven rollers 61, 62 such that adhesive is supplied to both surfaces of web 15 coming from supply roll 54. Cavity end guides (not shown) enclose the cavity 172 and a level control overriding pump 167 eliminates any possibility of overflow. A roll space actuator 174 is provided for controlling the spacing of rolls 61, 62. In another embodiment (Fig. 4 not shown) the adhesive from tank 64 is fed by pump 167 and manifolds 170 on to a revolving spreader roll 178 for applying adhesive to sheets 175 conveyed on conveyer 14. The roll 178 may be adjustable relative to the surfaces to be coated to control the adhesive film depth and other adjustable damming devices may be used. A further adhesive applying system (shown dotted) may be provided for coating the underside of sheets 175. In both embodiments the pumping volume is observed during designated periods or continuously by counters 183. Also the surface area moving to the application location is observed by using a fixed light and photo-cell 185-186 (Fig. 3) or a fixed location gap detector 187 (Fig. 4) each sending a signal to respective counters 188. In Fig. 3 an automatic summing system is schematically illustrated. The data from the pumping counter 183 and the surface counter 188 is analysed in a calibrated adhesive spread rate indicator 190 and the actual rate is compared with a pre-specified rate resulting in the transmittal of a control signal as necessary to operate power controls 191 which are adjusted automatically to keep the entire apparatus tuned to the adhesive requirements, e.g. by controlling pump 167, mixer drive 162, spacer actuator 174 and web roll drive 196. The latter however may be optionally powered and controlled in reference to conveyer 14. In (Fig. 4, not shown) a system which operates only during selected periods is schematically illustrated. Thus a counter 188 is is pre-set to operate during the passing of a predetermined number of sheets 175 and when in operation controls the circuit of another counter 183 recording the pumping operation of pump 167. In this way the quantity of adhesive pumped per pre-determined number of sheets is known and this information can be analysed for automatic or manual adjustment as necessary. The invention may also be used for applying decorative, protective and/or preservative materials on passing surfaces.