Patent GB-1135745-A (GB)
Title: Sheet feed control mechanism
IPC: G03G15/00
Filed: 1965-12-14
Abstract: 1,135,745. Feeding sheets. RANK XEROX Ltd. 14 Dec., 1965 [31 Dec., 1964], No. 24629/67. Divided out of 1,135,742. Heading B6B. In sheet feeding apparatus wherein a separator feeds sheets seriatim from the top of a sheet stack to feed rollers, the separator and rollers are driven alternately from a drive-shaft by means of an armature and two clutch elements, the clutch elements being energized in sequence to move the armature axially of the drive-shaft, first to engage one clutch, and then the other. Separators.-The sheets 287 are supported in a tray 20 which is raised to maintain the height of the stack substantially constant. The separator comprises two driven friction rollers 367 fixed on a shaft 368 mounted rotatably in a hollow arm 371 adapted to pivot about the axis of a shaft 372, and a pulley (373, Fig. 3) secured to the shaft 368 through a slip clutch (374) is connected by a timing belt (376) to a pulley (375) secured to the shaft 372. The shaft 372 is journalled in a fixed bearing (377) at one end, and the other end is notched and urged by a spring (380) endwise into engagement with a drive pin on the end of a coaxial shaft (S.H.3) which is connected by belt and pulley means to a drive-shaft (S.H.4). The hollow arm 371 is secured to a sleeve (388), rotatable on the shaft 372, which has a notch-and-pin connection with a second sleeve (385) having a cam arm (394) secured thereto. The cam arm engages a pin (395) to limit the downward movement of the arm 371 and separator rollers 367 under gravity. Sheet guides; sheet registration; feed rollers.- A separated sheet is guided by plates 392, 393 to feed rollers (280, 281, Fig. 2), the roller (280) being positively driven by a shaft (S.H.6), which is connected by belt and pulley means to the drive-shaft (S.H.4) which drives the separator rollers, and the roller (281) being urged by a spring (286) against the roller (280). The separated sheet is fed forward to such an extent by the separator rollers 367 that its front end engages, and is registered by, the bite of the stationary feed rollers (280, 281), and the sheet is buckled. When the feed rollers are driven, they feed the sheet between guide plates (282, 283) to the drum (14) of a xerographic printing machine described in Specification 1,135,742. Driving arrangements.- The drive - shaft (S.H.4, Fig. 4) is rotatable in bearings in side frames (5, 215), and is driven by a pulley (446) and timing belt (448) from a shaft (S.H.7) carrying the drum (14), and the drum shaft is driven by a motor and belt-and-pulley means. On the drive-shaft (S.H.4) is keyed an armature clutch element (436) which can slide axially of the shaft to engage, and drive frictionally, either of two magnet clutch elements (434, 435) freely mounted on the drive-shaft. When the element (434) is energized to attract the armature (436), the element drives the shaft (S.H.3) of the sheet separator by means of a belt (443) and pulley (442); and when the element (435) is energized to attract the armature, that element drives the shaft (S.H.6) of the feed rollers by means of a belt (445) and pulley (444). The clutch elements are energized by slip-rings under the control of a cam (455) on the drive-shaft (S.H.4).