GB1116885A - Improvements in or relating to a tanning machine - Google Patents

Abstract

<PICT:1116885/C6-C7/1> <PICT:1116885/C6-C7/2> A tannery machine, in which raw skins are treated with water or an appropriate liquor (hereinafter referred to as liquor) to effect one or more of the following operations, namely: soaking, rinsing, depilation, alkalinization, e.g. liming, acidic bating or drenching, acidic pickling, chrome or vegetable tanning, is preferably made of high grade steel, plated metal or plastics, and comprises a perforated drum 1, Figs. 1 and 3, having a door 2, through which skins can be fed into, or discharged from, the drum. The drum can be rotated, e.g. at 2 to 15 r.p.m., about its longitudinal, e.g. horicontal, axis, in a vessel 3 containing the liquor, and can be removed from the vessel in a direction normal to said axis, e.g. in a vertical direction, as by a crane or grab, whose lifting hooks engage projecting pins or rings 11 on the drum. The drum may be cylindrical and the vessel 3 may have a part-cylindrical base spaced 5 c.m. from the periphery of the drum. The base of the vessel 3 may be surrounded by a steam jacket for heating the liquor. A probe 5 is located in the vessel 3 to sense the pH of the liquor. The probe 5 is connected to an instrument 6, which measures the pH value, and displays this value on a dial 7, and controls valves 8a and 8b in pipes, respectively delivering acidic liquor from a container 9a or alkaline liquor from a container 9b, so that, whenever the pH of the liquor in the vessel 3 deviates from a desired, pre-set value the required amount of acidic or alkaline liquor for re-establishing said desired pH value is added automatically to the liquor in the vessel 3. Liquor may be supplied to the vessel 3 through an independent pipe, and may be drained off through a valve 4. The drum may be rotated by an electric motor 13 through a reduction gear and a driving belt.