GB1494304A - Method of and apparatus for working flexible sheet material - Google Patents

Abstract

1494304 Working flexible sheet material VYZKUMNY USTAV KOZEDELNY 21 May 1976 [23 May 1975] 20995/76 Heading C6C Flexible sheet material, especially leathers, are worked by continuously pressing the sheet between a pair of opposed rotatable rollers having protrusions and recesses so disposed therein as to form on each face of the continuously moving sheet a checkerboard pattern of protrusions and recesses. Apparatus comprises a press including a pair of opposed rotatable rollers 1, 2 each having side-by side peripheral series of teeth penetrating the intertooth spaces of the opposite roller, the teeth of each peripheral series being staggered in relation to the teeth of the next adjacent peripheral series so that on passing the sheet between the rollers the teeth deform the sheet to form on each face of the sheet a checkerboard pattern of protrusions and recesses. The press may comprise a pair of opposed toothed rollers, one being a supporting roller and the other a pressing roller. Each roller preferably consists of a series of toothed rings 11, 12, 21, 22 mounted side by side on a cylinder, each ring having the teeth thereof angularly displaced by half of the pitch of the teeth in relation to the teeth of the next adjacent ring on the cylinders. The pressing roller may be slidingly adjustable towards and from the opposed roller to provide for adjustment of the degree of penetration of the teeth of the pressing roller into the intertooth spaces of the opposed roller. A plurality of presses may be arranged in series and air jets are arranged between the presses. In another arrangement the presses are arranged inside a closed treating chamber. Alternatively the presses are arranged in a vat, and between the individual presses jets of tanning solution are arranged. In a first unit there are arranged one supporting roller in operative association with at least two pressing rollers. In a second unit there are arranged one pressing roller in operative association with at least two supporting rollers. The first and second units may be combined. The teeth of the supporting roller of the first unit penetrating the intertooth spaces of the pressing roller of the second unit. In the combined units, between the teeth of a hollow supporting roller the apertures are arranged, these apertures being connected with a vacuum space inside of the supporting roller. Also, between the teeth of a hollow pressing roller, apertures are arranged, these apertures being connected with a vacuum space inside the pressing roller. A cutting cylinder may be arranged at the entry to a press to cut the sheet prior to its passage between the rollers of the press.