GB752121A - Machine for the fabrication of hardenable foamy plastic - Google Patents

Abstract

752,121. Mixing appliances. SPUMALITANSTALT. March 5, 1954 [March 12, 1953], No. 6591/54. Class 86. [Also in Group XXI] A machine for the continuous production of hardenable foamy plastic consists of a coarse foam producer 24, Fig. 1, wherein compressed air from a pipe 25 passes upwardly through a horizontal fine mesh sieve 27, Fig. 5, to combine with a foam forming liquid possessing catalytic properties which is continuously supplied through a duct 26 to form a thin layer over the sieve 27, the coarse foam produced thereby passing into a horizontally elongated agitator unit 1, wherein a plurality of rotating horizontally elongated wire bristle rollers 8 closely spaced from each other and from the wall of the agitator unit reduce the coarse foam to fine foam and mix the fine foam with liquid synthetic resin forced through a pipe 32, which resin immediately begins to harden under the catalytic action of the foam. The foamy plastic is removed from the agitator unit while it is still not fully hardened by a rotating impeller 37 which delivers through a pipe 38. The rollers 8 consist of diametrically split tubes 12, Fig. 3, attached in pairs to shafts 11 by clamp rings 13 and the bristles 14 are formed in pairs bent from lengths of wire which are inserted from the interior through holes in the tubes and are secured by welding or screwing their connecting pieces 15 to the inside of the tubes. As described four wire bristle rollers are provided which are driven by means of a belt, Fig. 4 (not shown) and pulleys such as 19, 20 on the outer ends of the shafts 11 so that each roller rotates in the same direction as its diagonally opposed roller which is opposite to the direction of rotation of the pair of adjacent rollers. Each roller rotates at the same speed as its diagonally opposed roller which is different from the speed of rotation of the pair of adjacent rollers. The rear section of the agitator unit into which the liquid synthetic resin is added to the foam, is separated from the preceding portion of the agitator unit by discs 5 on the rollers and a baffle plate 6 on the container wall closely spaced from the discs 5, or by a rigid transverse wall with one or several openings therein. The liquid synthetic resin is supplied through a rapid action needle valve, Fig. 6 (not shown), which can be closed to prevent the foam from entering the feed line 32 of the liquid synthetic resin. In an alternative arrangement the rollers may be driven through a train of gears. The rollers may rotate at different speeds from each other.