GB1393029A - Abrasive rolls and machines incorporating such rolls - Google Patents

Abstract

1393029 Abrading J N KOKORAS and W N KOKORAS 1 June 1972 [3 June 1971] 25700/72 Heading B3D An abrasive roll or cylinder 24 for a hide treating machine comprises an abrasive body formed with a plurality of helical ribs 44 oppositely directed from a radial plane longitudinally bisecting the cylinder, each rib being thicker at its base than at its periphery. The roll or cylinder 24 is mounted on a shaft 32 having an enlarged part 52 provided with four keys 55 and a reinforcing cage 56 for the body which is cast around the part 52 and consists of a mixture of abrasive grains, such as emery, and an epoxy resin. The surface of the roll is formed with the helical ribs 44, the helix of which is opposite for different ends of the roll. The ribs are also tapered on each side so as to be thicker at their bases whereby as the diameter of the roll is reduced by wear or trueing the abrading action remains constant. The shaft 32 of the roll is mounted in bearings 26, 28 on standards 20, 22 and is driven by belts 38 from a motor. During rotation, the roll is also axially reciprocated by a sleeve 64 mounted on the shaft and having a reduced part engaged by ears 66 on a rod 68 having an enlargement receiving an eccentric on a shaft 70 rotated by a motor. The roll is trued by a tool 76, Fig. 4, such as a single diamond or a multiplicity of diamond chips in a metal matrix, carried by a transversely adjustable slide 88 mounted on a plate 88 movable along guide rods 82 parallel to the axis of the roll by rotation of a lead screw 84. The hide to be treated is drawn through the machine by a feed roll 98 driven by a chain 106 from a motor 112, the roll having a friction covering and being supported by bearings 102 on bars 100 pivoted to the frame and urged downwardly to positions determined by adjustable nuts 116 by springs 113. The hide is presented to the abrasive roll by upper and lower support rolls 118, 120 mounted on arms 124, 126 and interconnected by chains 132 so that the lower roll rotates at a slower speed than the upper, the hide being pinched between the upper roll 118 and the driven roll 98 and the upper and lower rolls being spaced a distance greater than the thickness of the hide from the abrasive roll 24. The rolls 118, 120 are movable between a retracted and an advanced position by pivoting of the arms 124, 126 by arms 140 forming levers with the arms 124, 126 and connected by spring loaded lost motion connections 154 to rods 148. The rods are pivotally connected to arms 146 keyed to shaft 145 and connected to the rod of an hydraulic cylinder 142, actuation of which by a foot controlled valve advances the rolls 118, 120 to a position determined by adjustable stops 166.