GB947435A - Folding apparatus for sheets and like flat work - Google Patents

Abstract

947,435. Folding sheets &c. CHICAGO DRYER CO. Jan. 16, 1962 [Jan. 31, 1961], No. 1515/62. Heading D1S. Folding apparatus for sheets &c. comprises a number of conveyers 24, 26, 28 which are at least in part superimposed over each other and each of which moves in the opposite direction to the successive conveyer and folding means associated with the conveyers to fold the conveyed articles, the article receiving end of each conveyer being situated beneath an overlying conveyer so that a conveyed article engages both conveyers in the course of transfer therebetween and each lower conveyer travelling at a greater speed than the immediately overlying conveyer. The conveyers 24, 26, 28 comprise a number of tapes passing around rollers 20, 20a. Sprockets 46, 48, 50 fixed to the rollers 20a are driven by a motor 36 and are of diminishing size so that the conveyer 26 moves faster than the conveyer 28 which moves faster than the conveyer 24. A sheet S is fed from the discharge conveyer 30 of an ironer on to the conveyer 24 with its selvedges lying along the length thereof. The leading edge L of the sheet S deflects an arm 54, Fig. 3, to close a switch 56 which does not actuate any apparatus until the sheet S has proceeded up inclined fingers 60 secured to a bar 62 and the edge L has deflected an arm 64 to close a switch 66. A coil in a four-way solenoid valve 70 (not shown) is energized to actuate a spring-biased valve therewithin to supply compressed air to the lower portions of cylinders 74, 76, Fig. 4. The piston rod 78 of the cylinder 74 moves upwardly so that, through the linkage shown, a clamping rod 90 pivots downwardly to clamp a forward portion of the sheet S against a fixed plate 57 slotted at 59 to allow movement of the arm 64. Upward movement of the piston rod 98 of the cylinder 76 causes the bar 62 to pivot to retract the fingers 60 to the position shown in Fig. 4. The portion of the sheet S contiguous with the clamped portion is carried on by the conveyer 24 and when the trailing edge T thereof disengages the arm 54 to break the circuit energizing the valve 70 so that the rod 90 is instantaneously released to allow the edge L to drop on to the edge T. A control device 116, Fig. 6 (not shown), is provided to control the rate of escape of air from the cylinder 76 so that the fingers 60 slowly return to their inclined position. The positions of switches 56, 66 are adjustable by turn-buckles 120. The half-folded sheet S passes on to the conveyer 28 which is inclined to the horizontal at an angle of less than 15 degrees and is quarter-folded by similar folding elements with the folded bight portion dropped beyond the edges L, T, see Fig. 1. The sheet S passes on to the conveyer 26, is delivered on to a platform 34, and is folded manually about fold lines F, Fig. 7, with the edges L, T inside. By deactivating the folding elements work may pass through the machine with no folding taking place. Examples of the relative speeds of the conveyers 24, 26, 28, 30 are given.