Patent GB-905907-A (GB)
Title: Improvements relating to sheet folding or other article processing apparatus and control systems therefor
Inventor: BUSS BENJAMIN ALVIN
IPC: D06F89/00
Filed: 1958-09-15
Abstract: 905,907. Control systems for folding fabrics. AMETEK Inc. Sept. 15, 1958, No. 29551/58. Class 42 (2). A control system for article processing apparatus, comprises a plurality of timing mechanisms each adapted to control operating means and having a rate of operation of its timing mechanism which is related to the rate at which the articles are fed through the apparatus, sensing means responsive to the length of an article and capable of controlling the duration of operation of each of the timing mechanisms and sequence controller means arranged sequentially to transfer control by the sensing means from one to the next of the timing mechanisms so that each of the timing mechanisms assumes control of the operating means for one of the articles, the sequence controller being adapted to perform its transfer function in two discrete steps, the first being performed as the article is being sensed, by a cam means operated by the sequence controller and the second step being performed by the cam means so as to transfer control to the next timing mechanism before the next article reaches the sensing means. As shown, the invention is applied to sheet-folding apparatus 10 which comprises a series of endless conveyer belts 11, 12, 13 driven by constant speed motor 14, a first folding means 15 opposite rollers 16 and 17 and a second folding means 18 opposite rollers 19 and 20. The folding means are preferable in the form of air jets issuing from a pipe across the width of the article to be folded. To control folding operations on successively fed sheets a plurality of timing mechanisms 200, 300, 400, 500 are provided, each of which may consist of sub-timing devices-one for each folding means. Each sub-timing device is controlled by sensing switch S-1 and a camactuated switch S-3, S-4, S-5, S-6 for the respective timing mechanisms. Sub-timing device 201 which controls folding means 15 is composed of a circular cam 31 having an indentation 32 and can be rotated by a highspeed motor 33 through an over-running clutch 34 or a low-speed motor 35 through over-running clutch 36. Switch 37, operated by the cam 31, controls the operation of the folding means 15 and switch 39 controls the energization of motor 33. Sub-timing device 202 is similar and controls the folding means 18. The timing mechanisms 300, 400 and 500 are composed of similar sub-timing devices for controlling the folding means 15 and 18. In operation, assuming initially only timing mechanism 200 is operated, when the leading edge of an article engages the sensing switch S-1, which has a portion extending between the belts 11, the member 51 of the switch is dis-engaged from contact 52 and engages contact 53. This energizes low-speed motors 35 and 43 and cams 31 and 41 rotate. Switches 39 and 48 are made but the high-speed motors 33 and 42 are not energized since the movable member 108 of cam-actuated switch S-3 is in contact with contact 112 and not contact 115. Cams 31, 41 rotate until the trailing edge of the sheet passes sensing switch S-1, at which time member 51 re-engages contact 52. At this point switch S-3 is operated by sequence-controller 100, as explained later, to move member 108 to contact 115 and thus energize high-speed motors 33 and 42 so that cams 31, 41 are rotated at high speed until followers 38 and 47 of switches 37 and 46 engage notches 32 to operate the folding means 15 and 18. The speed of the belt-drive motor 14 and the motors 33, 35, 42 and 43 are so related that the sheet is in the correct relative position when the folding means are actuated. To allow for rapid succession of sheets fed to the machine sequence controller 100 is provided to sequentially transfer the control information from switch S-1 to each of the timing mechanisms 300, 400 and 500 for successively fed sheets. The sequence controller, as shown in Fig. 2, comprises motor 105 driving cams 130 and 131. Cam-actuated switches S-3, S-4,S-5 and S-6 are positioned equidistantly around cam 130 and the time switch S-2 is actuated by cam 131. It will be seen that at any instant only one of the switches S-3 to S-6 is in actuated position wherein the low-speed motors of the timing mechanism can be energized by sensing switch S-1, and the timer-switch S-2 is alternatively actuated to one or other of its two positions. Referring back to Fig. 1, when the leading edge of a sheet operates sensing switch S-1 motor 105 is energized through lead 55 to rotate cams 130, 131. The low-speed motor of timing mechanism are also energized as explained above and the folding sequence initiated. The motor 105 rotates until timer switch S-2 is actuated to the dotted line position when the circuit to motor 105 is broken but the timing mechanism 200 continues to operate. The remainder of switches S-4, S-5 and S-6 are in their inoperative position. After the trailing edge of the sheet passes sensing switch S-1 the latter returns to its normal position, this then energizes motor 105 through lead 54 since member 103 of switch S-2 is in the dotted line position. Rotation of motor 105 now puts switch S-3 into its inoperative position and switch S-4 into its operative position and at the same time returns switch S-2 to its normal full-line position, thus breaking the circuit to motor 105. It will thus be seen that control has been transferred to timing mechanism 300 so that when the next sheet operates switch S-1 the sequence of folding operations is controlled by timing mechanism 300. After this sheet has passed, control is transferred to timing mechanism 400 by operating switch S-5, and for the next sheet to timing mechanism 500 by operating switch S-6 and then back to timing mechanism 200 by operating switch S-3 and so on, thus allowing rapid feed of sheets through the folding-machine.