GB937103A - Drying apparatus - Google Patents

Abstract

937,103. Drying veneers. FLEISSNER G.m.b.H. March 21, 1960 [March 26, 1959; April 20, 1959], No. 9875/60. Class 34 (2). Apparatus for the drying of substantially air-impermeable goods, e.g. veneers comprises at least one sieve-drum in a main drying zone associated with at least one preliminary or after-drying zone or an air-conditioned zone, the sieve-drum having means to generate a sufficiently strong suction current within the drum to cause the goods to adhere to the drum to be smoothed thereby. Substantially impermeable goods, e.g. veneers are dried in a preliminary drying zone 1, Fig. 3, which may comprise at least one belt drier from which the goods are transferred either directly or indirectly via adjustable rollers or slatted belts to the main drying and smoothing zone 3 comprising sieve drums having means to generate sufficiently strong suction current within the drums to cause the goods to adhere to and be smoothed by the drums, from whence the goods pass to an air-conditioned zone 4 comprising a belt drier, as shown, or a sieve-drum installation. The zones may be arranged in a single chamber, Fig. 6 (not shown), or the zones may be subdivided so that the speed, temperature or quantity of the drying air may be graduated therein, and the air flow may be in countercurrent in part or over the whole of the installation by mounting the air inlet of each zone adjacent the goods exit, as in Fig. 5 (not shown). The sieve drums may comprise two separate air flows, one being used for drying the goods by blowing air from nozzles. Thereover and removing the air laterally by suction and the other flow being used for generating a high suction current within the drum to obtain the smoothing effect. Partition plates may be mounted in each sieve-drum to allow one compartment thereof to be used for suction and the other for delivery, one or more fans being utilized in each drum. Nozzles may be arranged concentrically about the periphery of the sievedrums, the air issuing therefrom impinging on the goods being conveyed away through air ducts arranged concentrically between the nozzles to the part of the adjacent sieve-drums not covered by the goods. The sieve drum peripheries 16, Fig. 8A, may be formed with radially arranged, perforated entrainment elements 17 having suction bearing surfaces 15, the interiors of which elements have a negative pressure to obtain the smoothing effect on the goods introduced by their thin sides therebetween by a synchronized feed device, e.g. individual belts, which smoothing effect is enhanced by radiant heat outside or within the drum. In a modification, entrainment elements 21, Fig. 9, articulated together by pivotal connections 22, 23 convey the goods about a series of sieve-drums.