Electrophotography – Internal machine environment
Reexamination Certificate
2000-11-20
2001-12-25
Chen, Sophia S. (Department: 2852)
Electrophotography
Internal machine environment
C399S098000, C399S110000
Reexamination Certificate
active
06334033
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of Invention
This invention concerns maintaining the air pressure in a xerographic module of an image forming device.
2. Description of Related Art
This invention is related to co-pending application, Ser. No. 09/714,994, entitled, “Method and Apparatus for Controlling Humidity in a Copying Device,” filed on May 1, 2000, incorporated herein by reference in its entirety.
Many different types of image forming devices are available in the marketplace. Some of these devices employ a xerographic process for producing the images. In a typical xerographic image forming device, all elements are located in the same ambient atmosphere, and the air pressure throughout the entire image forming device is the same as the ambient atmospheric pressure. Because some of these devices employ fans and blower motors to direct air throughout parts of the image forming device, the air pressure throughout the machine may differ depending on whether a blower is operated or not. Typically, there is no specific compartment or module in the image forming device that is separated from the rest of the image forming device and maintained at a different pressure than the other parts of the image forming device.
SUMMARY OF THE INVENTION
As a result, contaminants from supplies used in the image forming device, such as paper and toner, are routinely circulated throughout parts of the image forming device. Also, contaminated room air is sucked into image forming device, including the xerographic module that might contain chemicals, dust and other contaminants. Filters and traps may be employed to reduce contaminants, such as, for example, toner, which has been picked up by air flowing through the image forming device, from adversely affecting components in other parts of the image forming device. Another source of contaminants are the image recording media used in the image forming device on which the image is formed and fixed. Contaminants from the image forming media include water vapor and image forming media fibers as well as toner applied to the image recording media throughout the xerographic process. However, even filters and traps will not eliminate contamination of xerographic system elements such as the imaging optics, the media transport elements, machine frames, toner bottles, and other elements.
The invention provides systems and methods for maintaining the pressure within a xerographic module of an image forming device within a specific range.
This invention further provides systems and methods that maintain the pressure in the xerographic module higher than the air pressure of the ambient atmosphere where the image forming device is located as well as outside of the xerographic module.
Maintaining a higher pressure in the xerographic module reduces the chance of contaminants from the image recording media entering and adversely affecting elements within the xerographic module. A positive pressure differential is maintained between the air pressure in the xerographic module and the air pressure both of the image forming device outside of the xerographic module and of the atmosphere in which the device is located.
In accordance with the systems and methods of this invention, an image forming device includes a xerographic module which includes various elements used to produce an image. Typically these elements include a light exposure device, a photoreceptor usable to generate a latent image, a developer unit that transfers toner to develop the latent image, a transfer unit that transfers the developed image to the image recording media, and a fuser. The xerographic module is located within a chamber in which the air pressure is maintained slightly above ambient pressure both within the other portions of the image forming machine and the surrounding atmosphere. This higher pressure within the xerographic module helps to prevent contaminants in unfiltered air from outside the xerographic module from entering into the xerographic module and contaminating the elements of the xerographic module or in some way adversely affecting the performance and condition of the xerographic module.
In a first exemplary embodiment of the systems and methods of this invention the xerographic module includes a pressurized semi-air-tight enclosure with a small gap between the xerographic module and the media path. This small gap prevents rapid loss of pressure from the xerographic module. A pressure sensor, such as, for example, an altimeter, is used to measure the ambient atmospheric pressure. A microcontroller is used to maintain the air pressure inside the xerographic module above the measured ambient atmospheric pressure.
These and other features and advantages of this invention are described in or are apparent from the following detailed description of various exemplary embodiments of the systems and methods according to this invention.
REFERENCES:
patent: 5467180, 19951100
patent: 5689766, 19971100
patent: 5946528, 19990800
patent: 6003608, 19991200
patent: 6266494, 20010700
Ankrom Dennis M.
Ayash Karl B.
Dergham Ali R.
Hollar Thomas C.
Chen Sophia S.
Oliff & Berridg,e PLC
Xerox Corporation
LandOfFree
Ambient atmospheric pressure compensation controller for... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Ambient atmospheric pressure compensation controller for..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Ambient atmospheric pressure compensation controller for... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2584111