Patent GB-1128349-A (GB)
Title: Improvements in or relating to a mechanism for transferring fabric pieces from stacks thereof
IPC: B65H3/22
Filed: 1966-04-15
Abstract: 1,128,349. Feeding sheets. L. & L. MFG. Inc. 15 April, 1966 [20 April, 1965], No. 16726/66. Heading B6B. A mechanism for feeding pieces of fabric one by one from the top of a pile of pieces to, for example, a feed conveyer has means whereby alternate pieces are turned upside down before being deposited on the conveyer. Sheet-separating and turning.- The pile 39, Fig. 2, of fabric pieces rests upon a foam rubber cushion 42 supported by a table 41 automatically raised as described below. A head 20 carrying the separating devices is fixed to a shaft 17 rotatably mounted in arms 12 pivoted at 13 and actuated by a lever-and-crank mechanism to move the head 20 from a position X where it engages the top piece of the pile to a position Y where it can deposit the piece on a conveyer 100. An endless chain arrangement engaging a sprocket on the shaft 17 maintains the head 20 horizontally during the movements. Mounted in the head 20 are two sandpaper-covered rollers 43, 44, Fig. 4, which, when the head 20 is over the pile, engage the top piece near its rear and leading edges respectively. A rack 48 engages a pinion 47 on the roller 43, and when a solenoid 53 is energized moves to the right to rotate the roller 33 clockwise. As the roller rotates it stretches the piece and at the same time picks up an edge portion of the fabric so as to separate the piece from the piece underneath it. A plate 59 may be associated with the roller 33 to obtain a positive pinching or gripping of the fabric. Energization of a solenoid 55 causes reverse rotation of the roller 33 to release the piece as described below. A similar rack-and-pinion arrangement 49, 50, and solenoids 54, 56 are provided for the roller 44. When the head 20 moves down on to the pile, spring-pressed rods 63, 64 engage the pile and are moved upwardly to close switches LS1 LS2, and cause the solenoids 53, 54 to be energized so that the top piece is separated and held by the head. The arms 12 are now operated to swing the head from position X to position Y. As described, the pieces in the pile have been cut from a stack of tubular knit fabric, so that if the top piece has the outside face of the tubular fabric uppermost, the next piece has the inner face uppermost, and so on throughout the pile. The mechanism operates so that all the pieces are delivered to the conveyer the same face upwards, i.e. alternate pieces have to be turned over. A piece with the outer face uppermost is carried by the head 20 to position Y where the solenoid 56 is energized to cause the leading edge of the piece to be released and to drop on to the conveyer 100. Subsequently, the solenoid 55 is energized to cause the release of the rear edge of the piece which is then carried forward by the conveyer. When the next piece is taken by the head 20, the release solenoid 56 is energized before the head reaches the conveyer 100 so that the released leading edge of the piece drops in front of a fixed plate 99. The trailing edge of the piece, is however, carried by the head 20 over the conveyer 100 and now becomes the leading edge as the piece is turned over. At position Y, the solenoid 55 is energized to release the piece which now has the same face upwards as the preceding piece. Subsequent pieces are alternately delivered without and with turning over. Air blasts directed downwardly and inwardly on to the top piece of a pile from openings in casings 97, 98 in the head 20 pass through the top piece and assist separation. Raising pile table.-The table 41 is attached to the piston 67 of a pneumatic cylinder 68, and a feeler 78 engaging the top of the pile or a cam-operated switch controls the admission of pressure air to below the piston so as to raise the pile as the pieces are removed. When the pile is exhausted, a second feeler 80 operates to cause the admission of pressure air to the top of the cylinder to lower the pile table 41 and at the same time effects stoppage of the motor 29 driving the crank mechanism of the arms 12. Sheet smoothers.-An air jet 95 above the conveyer 100 serves to smooth out small flaps that may be formed on the pieces by the rollers 33, 34. Detecting faulty sheet feed.-Beyond the jet 95, another air jet 109, Fig. 1 (not shown), controlled by a photo-cell detector device, blows off the conveyer 100 any pieces deposited incorrectly on the conveyer.