Patent GB-1029876-A (GB)
Title: A fabric shearing machine
IPC: D06C13/00
Filed: 1964-08-19
Abstract: 1,029,876. Shearing fabrics, K.A.MULLERS. Aug. 19,1964 [Sept.21, 1963], No.33834/64. Heading D1S.  A fabric shearing machine of the kind comprising one or more shearing cylinders 7 each supplied with a ledger blade 10, a shearing bed 14 and a nap or pile raiser (not shown), wherein the cylinder 7, the speed of the fabric, a mechanism for adjusting . The depth of the cut, and displacement devices for raising the cutting tool during the passage of a fabric seam are controllable in a continuously variable manner, is characterized in that the machine incorporates a programme control system whereby all functions including the number of fabric traverse and the corresponding depths of cut may be preset and adjusted independently and controlled fully automatically within the machine. The machine comprises a double pump 2 driven by an electric motor 1. The larger pump 2a supplies oil through a volume governor 3 and  a four-way valve 4 to a hydraulic motor 5 which drives the shearing cylinder 7 in the cutting direction through a belt drive 6. The governor 3 regulates the speed of the cylinder 7 and the valve 4 may be used to reverse the direction of rotation of the cylinder 7 necessary when a new cylinder 7 or blade 10 is to be knitted, the drive to the cylinder 7 being turned off in the median position of the valve. The smaller pump 2b is connected to a pressure reservoir 8 from which pressurised oil is drawn through control valves 9,11,13,15, respectively, to lift the cylinder 7 off the blade 10 when the latter has to be reground, to displace the nap or pile raiser through a linkage 12, to displace the shearing table 14 following a thick selvedge and to displace the table 14 towards and away from the cylinder 7. A second driven double pump 17 comprises a larger pump 17a which acts through a volume governor 18 and a four-way valve 19 to drive a hydraulic motor 20 which drives feed rolls 21, 22 for the fabric through gears 23, 24. The oil circuit of the pump 17a includes a three-way valve 25 by which the oil of this pump may be turned off when a low or crawl speed of the fabric is required and flow back into a tank 26. The pump 17b delivers into the hydraulic motor 20 so that a constant crawling motion is available at all times. A spindle 27 driven by a geared motor 28 is used to adjust the depth of cut. The brush rolls (not shown) and the nap or pile raising roll are driven by motors (not shown). The seam sensing device, Fig. 3, comprises one or more sensing strips or bars 31, 32 linearly displaceable with respect to guide rollers 29, 30 by a seam 33 and act on switches 34, 35 to transmit a signal to the cutting tools. The machine is provided with a counting device to record the number of preselected fabric traverses completed and a sonic or visual warning device to indicate the termination of the programme. The automatic operations are controlled through controllable time relays A control panel, Fig. 2 (not shown), is employed to operate the machine and comprises knobs for automatic and manual operation of the machine, to actuate the shearing cylinder, to set the feed rolls to working motion or crawling motion, to effect an emergency stop, to increase or reduce the depth of cut, to raise or lower the shearing table, to displace the pile or nap raiser, to reverse the machine in crawling motion, to actuate the governor 18 for fabric speed control, to actuate the governor 3 for shearing cylinder speed control and to act on a pressure reducing valve 52a for fabric tension control. An embodiment in which the severed pile ends are removed through a suction nozzle 54 is described, Fig. 4 (not shown). The operation of the shearing machine during the passage therethrough of a fabric having an angled seam is described.