Sheet feeder with dynamic speed control
AssigneeTohoku Ricoh Co., Ltd.
InventorKenji Endo
Life of this patent
Estimating the term…
Abstract
A sheet feeding apparatus for image processing systems such as a stencil duplicating machine or a copying machine comprises a sheet feeding time sensor, and a control unit. The control unit compares a sheet feeding time detected by the sheet feeding time sensor with a predetermined reference sheet feeding time, and controls a revolution speed of a sheet feeding roller during or after a sheet feeding operation.
Claims27
A sheet feeding apparatus for an image processing system which includes register rollers periodically conveying a sheet from a sheet feed roller to a printing section, the sheet feeding apparatus comprising:
- (a) a sheet feeding time sensor for detecting a sheet being positioned upstream of the register rollers in a sheet feeding path;
- (b) a control unit for comparing the sheet feeding time detected by the sheet feeding time sensor with a reference sheet feeding time out of experimentally predetermined sheet feeding times, and controlling a revolution speed of the sheet feed roller on the basis of a compared result during or after a sheet feeding operation;
- and
- (c) a sheet kind sensor, wherein when the sheet kind sensor detects a thickness of a sheet, a sheet feeding time of a sheet of the detected thickness is compared with a reference sheet feeding time predetermined for the corresponding sheet kind.
A sheet feeding apparatus for an image processing system which includes register rollers periodically conveying a sheet from a sheet feed roller to a printing section, the sheet feeding apparatus comprising:
- (a) a sheet feeding time sensor for detecting a sheet being positioned upstream of the register rollers in a sheet feeding path;
- and
- (b) a control unit for comparing the sheet feeding time detected by the sheet feeding time sensor with a reference sheet feeding time out of experimentally predetermined sheet feeding times, and controlling a revolution speed of the sheet feed roller on the basis of a compared result during or after a sheet feeding operation,
- wherein the sheet feeding time sensor detects sheet feeding times of a plurality of sheets, and an average of detected sheet feeding times is compared with the reference sheet feeding times.
A sheet feeding apparatus for an image processing system which includes register rollers periodically conveying a sheet from a sheet feed roller to a printing section, the sheet feeding apparatus comprising:
- (a) a sheet feeding time sensor for detecting a sheet being positioned upstream of the register rollers in a sheet feeding path;
- (b) a control unit for comparing the sheet feeding time detected by the sheet feeding time sensor with a reference sheet feeding time out of experimentally predetermined sheet feeding times, and controlling a revolution speed of the sheet feed roller on the basis of a compared result during or after a sheet feeding operation;
- and
- (c) an environment sensor for detecting factors such as temperature and humidity in the image processing system,
- wherein a sheet feeding time under the detected temperature or humidity is compared with a reference sheet feeding time predetermined for the corresponding temperature or humidity.
A sheet feeding apparatus for an image processing system which includes register rollers periodically conveying a sheet from a sheet feed roller to a printing section, the sheet feeding apparatus comprising:
- (a) a sheet feeding time sensor for detecting a sheet being positioned upstream of the register rollers in a sheet feeding path;
- (b) a control unit for comparing the sheet feeding time detected by the sheet feeding time sensor with a reference sheet feeding time out of experimentally predetermined sheet feeding times, and controlling a revolution speed of the sheet feed roller on the basis of a compared result during or after a sheet feeding operation;
- and
- (c) a multiple feed sensor for detecting multiple sheet feeding, disposed upstream of the register rollers in the sheet feeding path, and a sheet separating pressure regulating mechanism for regulating a sheet separating pressure,
- wherein when multiple sheet feeding is detected by the multiple feed sensor, the sheet separating pressure regulating mechanism regulates the sheet separating pressure.
A sheet feeding apparatus for an image processing system which includes register rollers periodically conveying a sheet from a sheet feed roller to a printing section, the sheet feeding apparatus comprising:
- (a) a sheet feeding time sensor for detecting a sheet being positioned upstream of the register rollers in a sheet feeding path;
- and
- (b) a control unit for comparing the sheet feeding time detected by the sheet feeding time sensor with a reference sheet feeding time out of experimentally predetermined sheet feeding times, and controlling a revolution speed of the sheet feed roller on the basis of a compared result during or after a sheet feeding operation;
- and
- (c) a sheet feeding pressure regulating member for regulating a sheet feeding pressure,
- wherein the sheet feeding pressure is regulated during or after the sheet feeding operation, on the basis of comparison between the reference sheet feeding time and the detected sheet feeding time, and
- wherein each time a detected sheet feeding time exceeds the reference sheet feeding time, no-sheet feeding is counted once, and the sheet feeding pressure is adjusted when the count of no-sheet feeding exceeds a predetermined value.
A sheet feeding apparatus for an image processing system which includes register rollers periodically conveying a sheet from a sheet feed roller to a printing section, the sheet feeding apparatus comprising:
- (a) a sheet feeding time sensor for detecting a sheet being positioned upstream of the register rollers in a sheet feeding path;
- and
- (b) a control unit for comparing the sheet feeding time detected by the sheet feeding time sensor with a reference sheet feeding time out of experimentally predetermined sheet feeding times, and controlling a revolution speed of the sheet feed roller on the basis of a compared result during or after a sheet feeding operation;
- and
- (c) a sheet feeding pressure regulating member for regulating a sheet feeding pressure,
- wherein the sheet feeding pressure is regulated during or after the sheet feeding operation, on the basis of comparison between the reference sheet feeding time and the detected sheet feeding time, and
- wherein only a predetermined sheet kind is specified, a detected sheet feeding time is compared with the reference sheet feeding time predetermined for the specified sheet kind.
A sheet feeding apparatus for an image processing system which includes register rollers periodically conveying a sheet from a sheet feed roller to a printing section, the sheet feeding apparatus comprising:
- (a) a sheet feeding time sensor for detecting a sheet being positioned upstream of the register rollers in a sheet feeding path;
- (b) a control unit for comparing the sheet feeding time detected by the sheet feeding time sensor with a reference sheet feeding time out of experimentally predetermined sheet feeding times, and controlling a revolution speed of the sheet feed roller on the basis of a compared result during or after a sheet feeding operation;
- and
- (c) a sheet kind setting member, wherein when the sheet kind setting member sets a sheet kind, a sheet feeding time of a sheet of the set kind is compared with a reference sheet feeding time predetermined for the corresponding sheet kind.
Dependencies are inferred from the claim text.