Conveyor mechanism and a method for adjusting a conveyor mechanism

Patent metadata

Field	Value
Publication number	US-2016137447-A1
Application number	US-201514943823-A
Country	US
Kind code	A1
Filing date	Nov 17, 2015
Priority date	Nov 18, 2014
Publication date	May 19, 2016
Grant date	—

Abstract

The present invention provides a conveyor mechanism for conveying sheets. The conveyor mechanism comprises a movable conveyor body, a drive mechanism, and an adjustment system configured to detect and correct skewing of the conveyor body, comprising one or more markers provided on or in the conveyor body, a sensor arrangement for detecting each marker at two or more discrete positions, and a processor to determine the skewing of the conveyor body. The conveyor body and the drive mechanism of the conveyor mechanism are mounted on a movable conveyor frame, and the adjustment system includes a frame shifting device comprising one or one or more actuator for shifting or moving the conveyor frame relative to a fixed framework. The invention also provides a related method of correcting skewing in a conveyor mechanism for conveying sheets along a transport path.

First claim

1 . A conveyor mechanism for conveying sheets along a transport path, such as sheets of a print medium in a printing system,
wherein the conveyor mechanism comprises a movable conveyor body configured to hold a plurality of sheets, such that movement of the conveyor body conveys the sheets along the transport path, and a drive mechanism which supports, and drives the movement of, the conveyor body to convey the sheets along the transport path, the conveyor mechanism further comprising an adjustment system configured to detect and correct skewing of the conveyor body as it conveys the sheets along the transport path, the adjustment system comprising:
one or more markers provided on or in the conveyor body;
a sensor arrangement for detecting each marker at two or more discrete positions spaced apart from one another by a predefined distance along the transport path; and
a processor for processing data or signals provided or generated by the sensor arrangement to determine the skewing of the conveyor body as it conveys the sheets along the transport path,
wherein the conveyor body and the drive mechanism of the conveyor mechanism are mounted on a movable conveyor frame, and the adjustment system comprises a frame shifting device comprising one or one or more actuators for shifting or moving the conveyor frame relative to a fixed framework.

2 . A conveyor mechanism according to claim 1 , wherein the one or more actuator, such as a servo motor, is arranged for driving movement of the conveyor frame, especially pivoting movement or rotational movement of the conveyor frame, with respect to a reference axis, movement of the conveyor frame being determined based on the data or signals from the sensor arrangement in relation to detected skewing of the conveyor body to compensate or correct for the detected skewing; wherein the processor is configured to analyse the data or signals from the sensor arrangement to determine the skewing based on a deviation of any of the markers with respect to the first or second skew sensing axes between the first and second sensor devices, and to control operation of the frame shifting device to correct the skewing by pivoting or rotating the conveyor frame to a required degree about the reference axis.

3 . A conveyor mechanism according to claim 1 , comprising a plurality of markers which are distributed or spaced apart along a length or extent of the conveyor body, wherein each marker is preferably fixed with respect to the conveyor body, and wherein each marker is uniquely identifiable or distinguishable by the sensor arrangement.

4 . A conveyor mechanism according to claim 3 , wherein each of the plurality of markers is distributed or spaced apart along the length or extent of the conveyor body at a unique spacing or distance, such that each marker is uniquely identifiable by the sensor arrangement, wherein each marker preferably comprises an aperture or hole in the conveyor body.

5 . A conveyor mechanism according to claim 1 , wherein the sensor arrangement comprises a first sensor device provided at a first position for detecting each marker and a second sensor device provided at a second position for detecting each marker, the first position and the second position being spaced apart from one another by the predefined distance along the transport path.

6 . A conveyor mechanism according to claim 5 , wherein the first position of the first sensor device and the second position of the second sensor device are provided on a frame member which provides or sets the predefined distance, the frame member preferably being substantially insensitive to temperature change.

7 . A conveyor mechanism according to claim 5 , wherein the first sensor device has a first skew sensing axis at the first position and the second sensor device has a second skew sensing axis at the second position, the first and second skew sensing axes extending generally parallel to the transport path, wherein the first and second sensor devices are respectively configured to detect each marker with respect to the first and second skew sensing axes.

8 . A conveyor mechanism according to claim 7 , wherein a deviation of a marker with respect to the first or second skew sensing axes between the first and second sensor devices represents a skewing of the conveyor body.

9 . A printing system comprising a conveyor mechanism according to claim 1 for conveying sheets of print medium, wherein the adjustment system is configured to determine and correct skewing of the conveyor body which holds the sheets in an image forming device for printing an image on the sheets.

10 . A method of adjusting a conveyor mechanism to correct skewing of a conveyor body which conveys sheets along a transport path, the conveyor mechanism having a movable conveyor body configured to hold the sheets, such that movement of the conveyor body conveys the sheets along the transport path, and a drive mechanism which supports and/or drives the movement of the conveyor body to convey the sheets along the transport path, the method comprising:
providing one or more markers on or in the conveyor body and distributed or spaced apart along a length or extent of the conveyor body; sensing or detecting each marker via a sensor arrangement at two or more discrete positions spaced apart from one another by a predefined distance along the transport path; processing data or signals provided or generated by the sensor arrangement to detect and/or determine skewing of the conveyor body as it conveys the sheets along the transport path; and moving a conveyor frame of the conveyor mechanism by pivoting or rotating the frame about a reference axis to correct the detected skewing.

11 . A method according to claim 10 , wherein the processing step comprises analysing the data or signals from the sensor arrangement to determine the skewing based on a deviation of any of the markers with respect to a first or a second skew sensing axis of the first and second sensor devices between first and second positions.

Assignees

• Oce Tech Bv

Inventors

• Smeyers Johannes H L
• Albers Antonius G H
• Jacobs Roy H R
• Janssen Cornelius M F
• Winarto Reinoldus F
• Clevers Ernest J J

Classifications

• B65H5/004 Primary

  using electrostatic force · CPC title

• B65H5/021

  by belts · CPC title

• B65H7/20 Primary

  Controlling associated apparatus · CPC title

• B65H2553/512

  Operations & Transport · mapped topic

• B65H2553/41

  Photoelectric detectors · CPC title