Patent GB-1106808-A (GB)
Title: Improvements in and relating to ultra high speed folding
Inventor: CORNWALL JAMES EDWARD
IPC: D06F89/00
Filed: 1965-10-22
Abstract: 1,106,808. Folding sheets. THOMAS BROADBENT & SONS Ltd. 16 Aug., 1966 [22 Oct., 1965], No. 44719/65. Heading D1S.  A machine for automatically folding workpieces of flexible sheet material, e.g. textile fabric, paper or laundry flatwork, of the type comprising two pressure members 1, 2 at a fold station, a feed conveyor 3 leading to the fold station, driving means for the conveyor 3 and the members 1, 2 and means 9 for forming a bend in a workpiece and for directing the bend into the bight between the members 1, 2, is characterized by means 11, 12 to sense the passage of a workpiece 35 relatively to the fold station and in that the driving means is controllable by the means 11, 12 to temporarily decelerate the conveyor 3 and the members 1, 2 prior to operation of the means 9. In one embodiment, Figs. 1 and 2, the members 1, 2 comprise rollers which drive the conveyor 3 and a delivery conveyor 4. A conveyor 5 is driven by a roller 6. The conveyors 3, 4, 5 may each comprise a plurality of parallel tapes. The means 9 comprises an air pipe the discharge of air jets from which is controlled by a solenoid operated air valve 8. In. a modification (not shown), the means 9 comprises a folder blade. The rolls 1, 2, 6 are driven by a chain 14 driven by a sprocket 15 having conical faces at opposite sides thereof to alternatively engage a brake 16 or a driver 17 mounted on a shaft 18 on which the sprocket 15 is journalled. In operation, a workpiece 35 is fed by the conveyor 3 and when its trailing edge passes the sensing device 11 a solenoid 33 is energized to disengage a sprocket 26, which drives the shaft 18 through a chain 25 and a sprocket 24, from a high speed motor 30 and to engage a low speed motor 28 to decelerate the conveyor 3 and the rollers 1, 2. When the trailing edge of the workpiece 35 passes the sensing device 12 a. solenoid 22 is energized to draw the sprocket 15 into engagement with the brake 16 to stop the conveyor 3 and the rollers 1, 2. The solenoid 33 is instantaneously de-energized and a spring 32 engages the sprocket 26 with the motor 30. .  At a predetermined time after the energization of the solenoid 22, the valve 8 is opened so that air jets blow a bend of the workpiece into the bight between the rollers 1, 2. The solenoid 22 is then de-energized and a spring 21 engages the sprocket 15 with the driver 17 to cause the acceleration of the conveyor 3 and the rollers 1, 2 to the normal high speed. In a second embodiment, Figs. 3 and 4 {both not shown), in which the feed conveyor and the fold rollers are decelerated to a reduced speed and then accelerated back to the normal speed, a single sensing device (40) is provided. When the trailing edge of the workpiece passes the device (40) a solenoid (33) is energized to disengage a sprocket (26) from a high speed (30) and to engage it with a low speed motor (28). The valve (8) is opened and then the solenoid (33) is de-energized. In a further embodiment, Fig. 5 (not shown), when the trailing edge of the workpiece passes the sensing device a solenoid (22) is energized to disengage a sprocket (15) from a high speed motor (42) and bring it into engagement with a brake (16) to stop the conveyor and the fold rollers in a single step.