Electrophotography – Diagnostics – Consumable
Reexamination Certificate
1999-11-24
2001-08-07
Grainger, Quana M. (Department: 2852)
Electrophotography
Diagnostics
Consumable
C399S071000
Reexamination Certificate
active
06272295
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to an apparatus and method for effectively measuring and monitoring the filming level on a photoreceptor.
2. Description of the Related Art
Sensors have been used for many purposes in electrostatographic printing machines. For example, U.S. Pat. No. 5,574,527 describes a method and apparatus for sensing multiple process parameters with a single sensor in a printing machine. It is described that the sensor can be used to sense the photoreceptor belt seam to insure that the latent image is not formed on the photoreceptor belt seam, to sense the toner density to control the toner dispenser, to sense the photoreceptor charging, developer bias, image exposure and image processing systems, to sense the presence of copysheets in a paper transport, and to sense the type of copysheet. The sensor is described to be uniquely located in the printing machine in order to function as described. Sensing of photoreceptor filming with the sensor is not described.
Most typically, infrared densitometers such as extended toner area coverage sensors are used in association with developing stations to monitor the toner density on the photoreceptor in order to control the amount of toner dispensed.
U.S. Pat. No. 5,903,797 describes a method and apparatus for monitoring cleaning performance to predict printing machine cleaner life. The method and apparatus employ a sensor and artificial stress conditions to determine the cleaner brush life. In the method, a comparative analysis is done between the data from the monitoring of a normal cleaning residual toner particle mass and the data from the artificial stress conditions cleaning residual toner particle mass to predict brush cleaner life reliably. The monitoring is conducted in a non-printing area of the photoreceptor. It is described that degradation in the ability of the cleaning brush to remove toner particles from the photoreceptor becomes detectable under the artificial stress conditions. Monitoring of filming on the entire photoreceptor surface under normal printing conditions is not described.
SUMMARY OF THE INVENTION
It is an object of the present invention to develop a method for effectively and efficiently monitoring the filming level of substantially the entire surface of the photoreceptor. It is also an object of the present invention to develop a method that can detect unacceptable filming at any portion of the photoreceptor surface early on so that corrective action can be taken prior to failure. It is a still further object of the invention to develop an electrostatographic printing machine containing components that can effectively and efficiently carry out the desired monitoring of filming levels on the photoreceptor surface.
These and other objects are achieved by the present invention. The invention relates to a method for monitoring filming levels on a photoreceptor surface of an electrophotographic/electrostatographic printing machine, comprising scanning an enhanced toner area coverage sensor over the photoreceptor surface at a point downstream from a cleaning station that removes particles from the photoreceptor surface to measure the filming level on the photoreceptor surface, and continuing the scanning with the enhanced toner area coverage sensor to obtain a filming level profile of substantially all of the photoreceptor surface.
The invention also relates to a method for monitoring filming levels on a photoreceptor surface of an electrophotographic/electrostatographic printing machine, comprising beginning with a photoreceptor surface substantially free of any filming, and thereafter repeatedly scanning an enhanced toner area coverage sensor over the photoreceptor surface to measure the filming level on the photoreceptor surface, wherein the enhanced toner area coverage sensor is mounted at a point downstream from a cleaning station that removes particles from the photoreceptor surface.
The invention still further relates to a printing machine comprising a photoreceptor having an image forming surface, a charging station to provide a charge to the image forming surface of the photoreceptor, an exposure station to form a latent image on the charged image forming surface of the photoreceptor, a developing station to provide toner particles and develop the latent image on the image forming surface of the photoreceptor, a transfer station to transfer the developed latent image from the image forming surface of the photoreceptor, a cleaning station to remove residual toner particles remaining on the image forming surface of the photoreceptor following transfer, and at a point downstream from the cleaning station, an enhanced toner area coverage sensor mounted in a manner enabling movement of the sensor over the image forming surface of the photoreceptor.
REFERENCES:
patent: 5162874 (1992-11-01), Butler
patent: 5519497 (1996-05-01), Hubble, III et al.
patent: 5574527 (1996-11-01), Folkins
patent: 5606721 (1997-02-01), Thayer et al.
patent: 5887221 (1999-03-01), Grace
patent: 5903797 (1999-05-01), Daniels et al.
patent: 5950040 (1999-09-01), Mestha et al.
patent: 60-8882 (1985-01-01), None
patent: 2-275477 (1990-11-01), None
patent: 6-95555 (1994-04-01), None
patent: 10-63148 (1998-03-01), None
patent: 10-91003 (1998-04-01), None
Lindblad Nero R.
Mongeon Michael C.
Wilcox Raymond D.
Grainger Quana M.
Oliff & Berridg,e PLC
Xerox Corporation
LandOfFree
Apparatus including and use of an enhanced toner area... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Apparatus including and use of an enhanced toner area..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Apparatus including and use of an enhanced toner area... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2512199