GB1023431A - Apparatus and method for forming composition board - Google Patents

Abstract

1,023,431. Building panels. W. L. KNOWLES. Jan. 16, 1963, No. 2049/63. Heading E1B. [Also in Division B5] In. an apparatus for continuously extruding composition board from a mixture of lignocellulose fines and a resin the mixture is forced by a plunger or piston between two die members one of which has an uneven surface, e.g. grooved surface. As described the apparatus produces board of the form shown in Fig. 13 (not shown). The mixture in the hopper 140, Fig. 16 (not shown), is fed by a hopper vibrator 144 via a vibrating tray 135 and funnel guide 132 to a feed chamber box 106 located above the due members. The box 106 is provided with a plurality of agitator fingers actuated through a rack and pinion gearing. The lower die member 54, Figs. 17 and 19 (not shown), has a series of longitudinal grooves 74 and is located by pins which pass through an insulating plate 60, on a guide block 45. Aligned with the die 54 is a cooking member 62. Above and spaced from the die 54 is an upper die 95 which has a transverse notch 96 defining a rear portion which can be vertically adjusted, to vary the pressure on the material being extruded. A hand wheel operated shaft extends across the apparatus and through eccentrics it acts on brackets carried by the part 97 of the upper die for adjustment purposes. Aligned with the upper die 98 is an upper cooking member 98. Independently controlled heating elements 61 extend through the dies 54, 95 and the cooking members 62, 98. The material is pushed through the space between the die members 54, 95 by an electrically heated piston 66, Figs. 6 and 19 (not shown), which is fixed to a slide block 52 located on the block 45. The piston 66 has a horizontal part 69, Fig. 10 (not shown), with depending ribs 70 having frontal projection.72. The block 52 is connected by links 75 and a shaft 78 to a connecting rod 44 of the main drive shaft 38 which extends transversely of the apparatus and carries at one end a fly wheel and at the other a multiple belt pulley by which it is driven. The effective throne of the connection rod 44 may be adjusted through the mechanism shown in (Fig. 6) to vary the stroke of the piston 66 through the die members. A transversely reciprocable cut-off saw automatically cuts the board into lengths. Protrusions at the front of the upper die and the projections 72 on the piston define a varying feed path and so serve to ensure uniformity in the density of the extruded material. The upper surface of the board may be covered with a paint, paper, veneer, metal or plastics material.