GB519737A - Improvements in and relating to the production of moulded articles by immersion - Google Patents

Abstract

519,737. Moulding articles of cellulose derivatives by dipping. BRATING, K., and INTERNATIONAL CONTAINERS, Ltd. Sept. 29, 1938. No. 28307. [Class 87 (ii)] Cores are immersed in volatile - solvent solutions within a closed chamber, and the coating produced on the cores is dried in separate closed chambers, the volatile solvent being removed in two steps, namely, recovery by condensation in those chambers in which the concentration of solvent is such that it may form explosive mixtures with air, and recovery by suction in those chambers where the concentration is less. The solvent removed by suction is passed, for example, through activated carbon for recovery. The apparatus used may comprise one immersion chamber, two drying chambers and a charging chamber but as shown in Fig. 1, it comprises ten chambers through which cores 23 loaded into frames carried by supports 15 are traversed by a pair of endless chains 14. The chambers 4, 7 and 10 are immersion chambers, the chambers 5, 8 and 11 are those in which solvent vapour is condensed, and the chambers 6, 9 and 12 are those in which solvent vapour is removed by suction. The condensing means comprises cooling elements 33 located in the. base of each condensing chamber ; the con densed liquid may be drawn off through a tap 37. In each condensing chamber, also, are heating means 32 which, in conjunction with partitions 34, induce downward current of vapour through the cores. Vapour 'is with- . drawn from each suction chamber (and also from the immersion chambers and the charging chamber 13) by a pump through apertures such as 42. The suction chambers have heaters 38. The chain 14 moves intermittently, and during the periods of rest the following movements occur :-(a) In the immersion chambers 4, 7 and 10 : Hydraulic lifting means 28 raises mmersion baths 29 so that the cores carried by the lower frame are immersed. The baths are then lowered and the . supports 15 are rotated through 180‹ by means described below. The baths are again raised and the second lot of cores are immersed. The baths are lowered and the supports again rotated through 180‹. (b.) In the charging chamber: The frames carrying the cores are removed from and inserted in slideways 22 in the supports 15. (c) In the condensing, and suction chambers : The supports 15 are automatically rotated by belts 65 driven by electromotors 64. Each support 15 is fixed on a shaft 18 carrying loose wheels 16, which run on rails 17, and fast wheels 19 with which the belts 65 engage. At the belt locations the rails 17 dip, so that the wheels 19 engage the belts 65 firmly. The chains carry grippers 20 which engage the shafts 18. Guide wheels 24 engage guide rails 61, 62 to maintain the supports horizontal. During rotation of the supports the rails 61 are rocked aside by handles 78. Doors 26, 27 are provided between the chambers, and intercepting means 79, co-acting with the rollers. 24, level the supports before they pass through the doors. The supports are rotated manually when they are within the charging and immersion chambers, by a handle 77, chain 75 and belts 67 which co-act with the wheels 19.