GB905918A - Sheet feed control device - Google Patents

Abstract

905,918. Sheet separators. MILLER PRINTING MACHINERY CO. Feb. 25, 1960 [March 6, 1959], No. 6630/60. Class 100 (1). Control apparatus for a sheet feeder comprises a cyclically operable separating means movable into and out of contact with a pile of sheets to separate sheets one by one from the top of the pile, the separating means being actuated by one portion of an operating member having another portion connected to continuouslyoperable driving means, and manually operable means to vary the cycle of the separating means so that separation of the sheets is prevented, the manually operable means being located remote from and at all times out of direct contact with the separating means and being operable while the driving means continue to operate. As shown, a number of sheet-separating devices 4 each having a suction foot 5 is mounted for vertical reciprocation in guides 55 of a supporting structure 56, the feet 5 being thereby moved towards and away from a pile of sheets 3 on a pile support 2. Each device 4 is biased downwards by a spring 58 and is connected with a source of suction by a pipe 70. A bell-crank lever 62, pivoted at 6, engages by means of a fork 60 at one end thereof a pin 59 projecting from a collar 57 mounted on each device 4. The bell-crank levers are oscillated by means of continuously-driven cams 69 which engage follower rollers 68 mounted on the bellcrank levers. A detent 15 is secured to a shaft 12 adjacent to each bell-crank lever 62 and is movable by rotation of the shaft between positions in which it does and does not engage a laterally projecting portion 63a of the bell-crank lever, such engagement preventing oscillation of the bell-crank lever and thus vertical reciprocation of the associated device 4 while the cam 69 continues to rotate. An arm 12a is fixed to the shaft 12 at one end and at the other is pivoted to a bar 8 which is vertically slidable in a guide 7 carried by the structure 56 and which is spring-biased downwards. The bar 8 has a foot 9 which engages the top of a horizontal bar 17. The bar 17 is formed with slots 18 which engage over studs 16 on the supporting structure, and is biased towards the left by a spring 19 which is more powerful than the spring biasing the bar 8 downwards. The bar 17 is normally held in the chain line position by an eccentric 24 mounted on a shaft 22, in which position the detent 15 does not engage the portion 63a. In order to interrupt the separation of sheets the operator moves the eccentric 24 to the full-line position by means of a hand-crank on the shaft 22, whereby the bar 17 moves upwards and to the left, thus urging the bar 8 upwards and the detent 15 into engagement with the portion 63a. Separation is resumed when the eccentric 24 is moved back to the chain-line position. The detent 15 can be engaged with and disengaged from the portion 63a only when the cam follower 68 is in engagement with the high portion of the cam 69.