Patent GB-666764-A (GB)
Title: Method of and apparatus for the automatic folding of textile sheets, e.g. bedsheets
IPC: B65H45/101
Filed: 1947-06-11
Abstract: 666,764. Folding sheets. FOXWELL, D. July 12, 1948 [June 11, 1947], No. 15345/47. Class 42 (ii). A textile sheet (e.g. a bed-sheet, table cloth or the like), on emerging from a processing machine is drawn through a folder which folds it longitudinally along its central running line and, as a continuing step, the doubled sheet is then drawn through a second folder which similarly folds the already folded sheet. As shown, Fig. 1, a sheet x emerging from calender roller 10 is fed by a conveyer 11 between rollers 13, 14 and 15, 16 to intake rollers 20, 21 of a first folder, to be folded centrally over a triangular creasing plate 22 and passed by delivery rollers 25 to the creasing plate 22a of a second folder, whence it is delivered by a conveyer 35 to a plaiting machine 38 for transverse folding. The second folder is mounted on wheels 32 for transverse movement relative to the first folder which is itself mounted on wheels 27 for movement relative to the machine frame 17 in a direction at right-angles to that of the second folder. The centre line of the first folder is aligned with the centre line of the sheet by the action of feeler members 80, Fig. 3, adapted to engage the edges of the sheet as it passes between rollers 13, 14 and 15, 16. Feelers 80 are carried on brackets 52, 53 and are moved inwardly along rails 41, 42 by engagement of compressed-air-operated grippers 56, 57 with a continuously - moving chain 48. Inward movement of both brackets 52, 53 moves chains 62, 63 to rotate the opposite side bevels of a differential gear 66, the crown-wheel carrying a rod 67 remaining stationary. Engagement of a feeler with an edge x of the sheet arrests its inward movement by cutting off the supply of compressed air to the gripper; continued movement of the other feeler will then disturb the differential arrangement 66, causing rod 67 to swing so as to actuate one of two grippers 69, 69a mounted on a plate 68 carried by the folder. The gripper 69 or 69a while actuated causes plate 68 and hence the whole folder to move with chain 48 and at the same time reverses the operation of the differential ; the folder thus moves intermittently at half the speed of the moving feeler so that when the latter engages the sheet edge the folder has moved so that its centre line coincides with that of the sheet and the folder remains in this position. Similar mechanism aligns the centre line of the second folder with the centre line of the oncefolded sheet. Compressed air is supplied to the grippers only when a feeler projecting through conveyer 11 is depressed by a sheet passing thereover. when compressed air is cut off, feelers 80 are retracted to the sides of the machine by weights 70 ready for the next sheet. In each folder, the sheet may be guided over the creasing plate by thin flexible blankets passing over the intake and delivery rollers, or by a number of flexible endless bands passing around a series of pulleys which replace the intake and delivery rollers shown. The means for moving the folders into alignment with the sheets as located by feeler fingers may be electrically, instead of mechanically, controlled.