JPS62127851A - Cleaning device for image density sensor of copying machine - Google Patents

Abstract

PURPOSE:To obtain correct image density while always cleaning the surface of an image density sensor, by providing a cleaning brush on the sensor. CONSTITUTION:In the lower part of a photosensitive drum 17, an image density sensor 19 is provided in the inside of a carrying device 18. At every copying operation, a sensor mark of a reference density which is fixed to an original platen is developed onto the photosensitive drum 17, and synchronized when it has come right above the image density sensor 19, and the image density sensor 19 is operated. A carrying lever 28 which is attached to a bottom plate 20 supports the carrying device 18 by a pushing-up member 24,therefore, this device consists of a mechanism by which the pushing-up member 24 is inclined and the carrying device 18 descends to the bottom plate 20 by rotating counterclockwise the carrying lever 28. Also, a slide plate 21 on which a brush 22 is attached to the tip slides along a guide pin 23, and drawn in the right direction by a tension spring 27.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an image density sensor cleaning device for electrostatic transfer copying machines and the like.

Conventional technology FIG. 3 is a schematic diagram showing a conventional copying machine.

Conventionally, as a toner density control method, after the photoreceptor drum 1 is charged by the charger 4, a reference density sensor mark 14 attached to the document table 16 is exposed on the photoreceptor drum 1, and the developing device 2 is activated. As described above, the density of the developed image on the photosensitive drum 1 is read by the image density sensor 8, and when the output of the image density sensor 8 falls below a reference level, toner is replenished to the developing device 2.

Further, when the transfer paper is distorted on the conveyance device 3, the conveyance device 3 is moved in the input direction about the drive shaft 12 by moving the conveyance lever 9 in the B direction.

Problems to be Solved by the Invention However, with the above configuration, the image density sensor 8 disposed on the conveying device 3 prevents the toner in the developing device 2 from spreading during the copying operation and causing the toner to spread onto the photoreceptor drum 1. Image density sensor 8 may be damaged due to scattered toner after development.
There has been a problem in that the toner adheres to the lens portion on the top surface, and as a result, the image density sensor 8 does not operate properly and proper image density cannot be obtained.

In view of the above-mentioned problems, the present invention is a copying machine that wipes off toner adhering to the top surface of the image density sensor by moving a release lever on the conveyance device to move the brush disposed on the top surface of the image density sensor from side to side. The purpose is to provide a complete image density sensor cleaning device.

Means for Solving the Problems In order to solve the above-mentioned problems, the present invention provides a cleaning brush in the transport device that moves from side to side by moving a transport lever to clean the dirt on the surface of the image density sensor. It is something.

Function The present invention has the above-described structure, so that even if toner scatters and adheres to the surface of the image density sensor, the cleaning brush cleans the image and the surface of the image density sensor by simply moving the conveyance lever. Image density can be obtained.

EXAMPLES Below, examples of the present invention will be described with reference to FIGS. 1 and 2. FIG. 1 is a side view of an electrostatographic copying machine equipped with a cleaning device according to the present invention, and FIG. 2 is an enlarged view of essential parts of the cleaning device.

In FIG. 1, an image density sensor 19 is disposed below the photosensitive drum 17 inside a conveying device 18. As shown in FIG. During each copy operation, a sensor mark of standard C degree fixed to the document table is developed on the photosensitive drum 17, and the image density sensor 19 is activated in synchronization with the time when the image is placed directly above the image density sensor 19. It has become.

j Since the conveying lever 28 attached to the forming board 20 supports the conveying device 18 by the pushing up member 24, by rotating the conveying lever 2B to the left, the pushing up member 2
4 is a mechanism in which the conveying device 18 descends to the bottom plate 20 by tilting. ``Also, the slide plate 21 with the brush 22 attached to the tip slides along the guide pin 23, and the tension spring 27
is being pulled to the right.

In the above-described structure, by rotating the conveyance lever 28 to the left, the conveyance device 1B is lowered and the bottom plate 20 is lowered.
The slide row 225 of the slide plate 21 slides along the guide plate 26 fixed to.

The bluff 22 of the slide plate 21 wipes the surface of the image density sensor 19. Furthermore, when the transport lever 28 is returned to the right, the brush 22 similarly moves to the right, thereby cleaning the surface of the image density sensor 19.

During normal copy operation, the brush 22 and slide plate 2
1 is hidden within the conveying device 18, so that it does not adversely affect the running of the transfer paper or the reading by the image density sensor 19.

Image by moving the transport lever 28 and using the bluff 22 in the market! The sensor 19 can be cleaned once by a service person when cleaning the sensor or during regular maintenance. Since the amount of toner and paper dust from the transfer paper scattered on the image density sensor 19 is small, it is possible to completely restore the original sensor sensitivity by moving the conveyance lever 28 left and right four to six times during regular maintenance.

The material of the brush may be any soft material that does not damage the resin on the surface of the image density sensor 19.

Effects of the Invention As described above, according to the present invention, by providing a cleaning brush on the image density sensor, the surface of the image density sensor can be cleaned simply by periodically moving the conveyance lever, and the scattered toner can be removed from the image. It is possible to prevent defects such as when toner adheres to the density sensor and the sensor sensitivity decreases, causing toner to no longer be replenished, resulting in a decrease in image density.

Furthermore, the above-described structure eliminates the difficulty of inserting one's hand into a narrow space inside the copying machine and cleaning the five image density sensors with a brush or air blower during maintenance.

[Brief explanation of drawings]

FIG. 1 is a side view of an electrostatographic copying machine equipped with a cleaning device according to the present invention, and FIG. 2 is an enlarged view of the cleaning device. FIG. 3 is an explanatory diagram of a conventional electrostatographic copying machine. 17... Photosensitive drum, 1B... Conveying device, 19... Image density sensor, 20...
...Bottom plate, 21...Slide plate, 22...
... Brush, 23 ... Guide pin, 24.2
4'... Pushing member, 25... Slide roller, 26... Guide plate, 27...
...Tension spring, 28...Transportation lever. l7- Photoconductor drum ta-*L*t I9- Image thick cliff sensor 20- Bottom Slope 21- Slide plate? ? - Brush 23 - Guide pin 24 - Push up 1ヂ@goods (1) 24' - Weighing member (2) Of course - JL & L lever 1 - Ram 2 on photoreceptor - Current cultivation 1 3 - Conveyance method 1 4 - f- Charger 5- Fail belt t! 6-Currently #111Ft device 7-Excluding ff111FtL 8-Iff image density height - 9-Transport lever 10-One-branch rod n-Evaluation member/2-U Gai Crow 13-One conveyor belt 16-Mirror

Claims (1)

[Claims] An image density sensor that reads the image density on the photoreceptor drum, a conveyance device in which this image density sensor is disposed and configured to move up and down, and a brush that cleans the image density sensor as the conveyance device moves up and down. An image density sensor cleaning device for a copying machine, comprising: