JP2002354215A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming device which interrupts copying to perform calibration by automatically detecting the period of calibration from the temperature dependence of the output characteristics of an image sensor and characteristics of the temperature rise caused by continuous print. SOLUTION: The number of copies in continuous copying is monitored, and when it reaches a prescribed number, continuous print is temporarily stopped to perform calibration.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a multifunction printer (MF) incorporating an image scanner or the like.
P) and the like.

[0002]

2. Description of the Related Art In the field of personal computer peripheral devices, there are products such as printers and image scanners. In recent years, a new product called a multifunction printer (MFP) combining these products has been released.

An MFP is a printer, an image scanner, an F
This product is a product in which the functions of the AX are integrated. For example, the product is connected to a host computer by a Vicentronics I / F, and transmits data read by an image scanner or data transmitted by a facsimile to the host computer, or a host computer. The created data is sent to a printer and printed by the printer. Further, a copying operation of reading by a scanner and printing by a printer can be performed by the MFP alone.

FIG. 2 is a schematic side view of an example of an image forming apparatus. In FIG. 2, 1 is a document table, 2 is a document, 3
Denotes a main motor, 4 denotes a paper feed roller, 5 denotes a laser unit, 6 denotes a process cartridge, 7 denotes a transfer unit, 8 denotes a fixing unit, 9 denotes a sheet discharge table, 10 denotes an engine controller, and 11 denotes a printer controller.

The above components are components of the printer unit. When receiving data from a host computer (not shown), the printer controller 11 sends a print command to the engine controller 10 and converts code data into dot data. The engine controller 10 receives the print command and drives the motor 3, the paper feed roller 4, the laser unit 5, the transfer device 7, and the fixing device 8.

As a result, a toner image is formed on the document 2 on the document table 1 based on the data developed by the printer controller 11, and is fixed by the fixing device 8, thereby completing the printing operation.

In FIG. 1, reference numerals 20 to 25 denote parts of an image scanner unit, reference numeral 20 denotes a document table, reference numeral 21 denotes a paper feed roller, reference numeral 22 denotes an image sensor, reference numeral 23 denotes a white sheet metal, reference numeral 24 denotes a discharge roller, and reference numeral 26 denotes a paper discharge roller. A motor 25 is a scanner controller. When the scanner controller 25 receives a read command with an operation button (not shown), it drives the motor 26, the paper feed roller 21, and the image sensor 22 to read the data of the original 1 and, via the printer controller 11,
Reads and sends image data to the host computer.
At the time of copying, data is sent from the scanner controller 25 to the printer controller 11, and the printer controller 11 prints based on this data.

Next, the image sensor will be described.
The image sensor includes a light emitting unit that irradiates the original with light, and an image reading element that detects the density of the original based on the intensity of the reflected light. The image reading elements are arranged in a line. For example, if an A4 document can be read at a resolution of 600 dpi, 5000 or more reading sensors are arranged in a line. By arranging the image sensor main body perpendicular to the document conveyance direction and controlling the motor to advance the document by 600 dpi and one dot at a time, 600 dpi × 60
It can be read at a resolution of 0 dpi.

Further, even if each sensor receives reflected light of the same intensity, the output varies (FIG. 3). Therefore, it is necessary to receive light having the same intensity and correct the light before the actual reading operation. In this example, the light is emitted before reading, and the reflected light is received by the white background plate 23 to perform the correction (FIG. 5).

This correction operation is automatically performed for the first sheet of a copy or scan start. Of course, it is designed so that the user can do it arbitrarily.

[0011]

However, the output of the above-described sensor in the conventional example is easily affected by an increase in the ambient temperature. For example, when 100 continuous copies are repeated, the heat of the fixing unit in the printer is reduced. As a result, the output of the image sensor may fluctuate (FIG. 4).

For this reason, there is a problem that the quality of the print sample after 100 sheets is deteriorated as compared with the first sheet.

In order to solve this problem, there is a means for correcting each time before reading each page during continuous copying, but this has caused a problem that the throughput is reduced.

Since the present invention has been made in view of the above problems, the timing of calibration is automatically detected in advance from the output characteristics of the image sensor with respect to the temperature and the temperature rise characteristics of continuous printing, and copying is interrupted. It is an object of the present invention to provide an image forming apparatus in which calibration is performed by performing the calibration.

[0015]

The present invention can solve the above-mentioned problems by providing the following constitution.

(1) An image forming apparatus comprising an image reading unit for irradiating a document with light and measuring the reflected light to read the document, and a printing unit for receiving and printing image data. The image reading unit has a reading unit correcting unit that receives a reference light and corrects a reading element, and corresponds to a result of a continuous printing sheet number detecting unit provided in the printing device unit. An image forming apparatus, wherein correction is performed using a unit.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an image forming apparatus according to the present invention will be described below.

FIG. 1 is a flowchart showing the operation of the image forming apparatus according to the embodiment of the present invention.

In this embodiment, the printer controller is a master and the scanner controller is a slave. That is, the scanner controller operates according to a command from the printer controller. In detail, FIG. 1 shows a part of the firmware provided in the printer controller.

In FIG. 1, when the printer controller 11 receives a copy command in step S00, it instructs the scanner controller 25 to perform calibration and then read an image.

The scanner controller 25 receives the command, performs calibration in step S01, and starts the scanner operation in step S02.

Thereafter, the printer controller 11 starts the printing operation in step S03, resets the continuous sheet number counter provided therein, and starts counting the continuous sheet number (step S04). Then, in step S05, 1
It is checked whether the copy is the 00th copy. If the copy is not the 100th copy, the copy operation is continued in step S08.

If the number is 100, it is determined that the temperature of the image sensor 22 has risen to a predetermined temperature or higher, and the printing operation is temporarily stopped in step S06, and the scanning operation is also stopped (step S07).

After returning to step S01 and performing calibration, the scanner operation and the printing operation are continued.

As described above, by using this means, it is possible to anticipate a rise in the temperature of the image sensor that occurs during continuous copying, and to correct the mismatch of calibration data caused thereby. Simultaneous automatic execution minimizes a decrease in throughput.

[0026]

As described above, continuous copying can be performed without deteriorating printing quality by monitoring the number of continuous printings of the printer during the copying operation and automatically performing calibration after a predetermined number of printings. , And has the effect.

[Brief description of the drawings]

FIG. 1 is a flowchart illustrating an operation of an image forming apparatus according to an embodiment of the present invention.

FIG. 2 is a schematic side view of an image forming apparatus as an example.

FIG. 3 is an explanatory diagram showing a variation in output of each sensor.

FIG. 4 is a comparative explanatory diagram of sensor outputs before copying of each sensor and after copying 100 sheets.

FIG. 5 is a flowchart showing an example in which light is emitted before reading and correction is performed by receiving reflected light from a white background plate 23;

[Explanation of symbols]

REFERENCE SIGNS LIST 1 document table 2 document 3 main motor 4 paper feed roller 5 laser unit 6 process cartridge 7 transfer device 8 fixing device 9 paper discharge table 10 engine controller 11 printer controller 20 to 25 parts of image scanner section (20 is a document table, 21 is a document table) Paper feed roller, 22 is an image sensor, 23 is a sheet metal on a white background, 24 is a discharge roller, 25 is a scanner controller) 26 Motor

Claims (1)

[Claims] An image forming apparatus comprising: an image reading unit that irradiates a document with light and measures reflected light to read the document; and a printing unit that receives and prints image data. The image reading unit has a reading unit correction unit that receives a reference light and corrects a reading element, and corresponds to a result of a continuous printing sheet number detection unit provided in the printing device unit;
An image forming apparatus, wherein the correction is performed using the reading unit correction unit.