JPH05204203A - Image forming device - Google Patents

Abstract

PURPOSE:To eliminate various kinds of failure occurring on paper immediately after applying a power source by providing a paper feeding means forcibly feeding the paper from a cassette after finishing initializing operation. CONSTITUTION:When the power source switch of a copying machine main body 1 is turned on, the initializing operation is performed. For example, heating a fixing roller pair 23a, moving 1st and 2nd carriages to a home position, and detecting the toner concentration of a developing device 12 are performed as the initializing operation. When the initializing operation is finished, test copying is started in synchronism with the finish of the action, and the paper P on the uppermost part is taken out from the paper feeding cassette 13 and fed to a transfer part by a resist roller pair 19 through a paper passage 17, then blank paper copying is performed. Since the blank paper copying is automatically performed when the power source is applied, the moist uppermost paper is forcibly ejected, the stain by oil and dew condensation in a machine body are eliminated and the temperature of the machine body is stabilized as the paper is ejected.

Description

Detailed Description of the Invention

 [Object of the Invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as an electronic copying machine or a laser printer.

[0002]

2. Description of the Related Art Conventionally, in an electronic copying machine, if the power is not turned on for a long time, the paper (image forming medium) in the cassette becomes moist, and especially the transfer failure occurs on the first paper. However, there are drawbacks such that the image is liable to occur, the image is soiled by the oil for preventing the stain applied to the fixing device from leaking out, or the image is defective due to the dew condensation in the sheet feeding and conveying section.

In cold regions, there may be a large temperature difference between the heat roller and the press roller even when the fixing device has reached the set temperature. In such a case, Has a drawback in that the paper tends to curl into a tubular shape.

[0004]

As described above, conventionally, there is a drawback that various inconveniences are likely to occur on the paper (copy image) immediately after the power is turned on. Therefore, an object of the present invention is to provide an image forming apparatus capable of eliminating various inconveniences that appear on an image forming medium immediately after power is turned on. [Constitution of Invention]

[0005]

In order to achieve the above object, in the image forming apparatus of the present invention, an image is formed on an image forming medium fed from a cassette. After the operation is completed, a sheet passing means for forcibly feeding the sheet from the cassette is provided.

Further, in the image forming apparatus of the present invention, when an image is formed on the image forming medium fed from the cassette, the sheet is forcibly fed from the cassette after completion of the initialization operation. Paper passing means for performing,
After the paper is fed by the paper passing means, it is constituted by control means for permitting acceptance of key input.

Further, in the image forming apparatus of the present invention, in the case where an image is formed on the image forming medium fed from the cassette, the initialization means for performing the initialization operation and the initialization means are used. When the initializing operation is completed, the ejecting means for ejecting the image forming medium from the cassette, the sheet passing means for conveying the image forming medium ejected by the ejecting means, and the image conveyed by the sheet passing means It is composed of operating means for forming a white background image on the forming medium, and control means for permitting acceptance of a key input after the white background image is formed by the operating means.

[0008]

According to the present invention, since the above-mentioned means can prevent the image from being formed on the uppermost sheet in the cassette, a good image forming operation can be performed on the first image forming medium after the power is turned on. It is possible to execute.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows the structure of a copying machine according to the present invention.

An original table (transparent glass) 2 for supporting an original is fixed on the upper surface of the copying machine main body 1, and a fixed scale 2a serving as a reference for setting the original is provided in the vicinity of the original table 2. .. The lower surface of the fixed scale 2a is made white by painting or sticking a white sheet material.
Further, the document cover 1a is arranged so as to cover the document table 2.
Is openable and closable.

For the original placed on the original table 2, the optical system including the exposure lamp 4 and the mirrors 5, 6, 7 is reciprocated in the direction of arrow a along the lower surface of the original table 2. Is used for exposure scanning. In this case, the exposure lamp 4 and the mirror 5 are supported on the first carriage, and the mirrors 6 and 7 are supported on the second carriage (neither is shown). Also, the mirror 6,
7 is moved at half the speed of the mirror 5 so as to maintain the optical path length.

The reflected light from the original by the scanning of the optical system, that is, the reflected light from the original by the irradiation of the exposure lamp 4 is reflected by the mirrors 5, 6 and 7 and then passes through the variable magnification lens block 8. Further, the light is reflected by the mirror 9 and guided to the photosensitive drum 10. As a result, the image of the document is formed on the surface of the photoconductor drum 10.

The photosensitive drum 10 is rotated in the direction of the arrow c in the figure, and the surface is charged by the charging charger 11 first. After that, the image is slit-exposed in the exposure unit Ph to form an electrostatic latent image on the surface. This electrostatic latent image is made into a visible image (developer image) by the toner attached by the developing device 12.

On the other hand, the paper (image forming medium) P is taken out one by one from the paper feed cassette 13 by the delivery roller 15. Then, the taken-out paper P is guided to the registration roller pair 19 through the paper guide path 17, and is sent to the transfer portion by the registration roller pair 19.

The paper feed cassette 13 is detachably provided at the lower right end of the copying machine main body 1, and the cassette size is detected by the cassette size detection switch 60a. As a result, the paper size in the cassette 13 is automatically detected. The cassette size detection switch 60a is composed of, for example, a plurality of micro switches that are turned on / off according to the insertion of cassettes of different sizes.

The sheet P sent to the transfer section is brought into close contact with the surface of the photosensitive drum 10 at the transfer charger 20, and the toner image (development) on the photosensitive drum 10 is developed by the operation of the charger 20. The agent image) is transferred. The sheet P on which this image is transferred is subjected to the action of the peeling charger 21 so that the photosensitive drum 1
The toner is electrostatically separated from No. 0, and is conveyed between the fixing roller pair (heat roller) 23a and the press roller 23b as a fixing device provided at the terminal end of the conveyor belt 22.
Each of the fixing roller pair 23a and the press roller 23b has a peeling claw 310 so that the paper P is not wound around.
a and 310b are provided. Then, the paper P on which the transfer image is fixed by passing through this is discharged to the tray 25 outside the copying machine main body 1 by the paper discharge roller pair 24.

After the transfer, the photosensitive drum 10 is destaticized by the decharging charger 26, the residual toner on the surface is removed by the cleaner 27, and the residual image is erased by the destaticizing lamp 28. It is supposed to be returned to. Reference numeral 29 is a cooling fan for preventing the temperature inside the copying machine main body 1 from rising. FIG. 2 shows an operation panel 30 provided on the upper surface of the copying machine main body 1.

The operation panel 30 is for operating the drive of an optical system, a paper feeding system, etc., and has a copy key 30a for instructing the start of a copy operation, a ten key 30b for setting the number of copies, a paper selection. A key 30c, a density adjustment key 30d, a magnification key 30e, a display panel 30f, a message panel 30g and the like are provided. next,
The operation of the above configuration will be described. Figure 3
It shows a flow of processing when the power is turned on.

For example, assume that a power switch (not shown) of the copying machine main body 1 is turned on. Then, first, an initialization operation (initialization operation) is performed. As the initializing operation, for example, heating of the fixing roller pair 23a, movement of the first and second carriages to the home position, detection of toner concentration of the developing device 12, and the like are performed.

Here, at various places in the main body 1 of the copying machine, for example, temperature sensors for detecting the arrival of the fixing roller pair 23a at the fixable temperature, and for detecting the return of the first and second carriages to the home position. A position sensor, a density sensor that detects the toner density of the developing device 12, and the like are provided, and the detection signal from each of these sensors is checked by a microcomputer to determine the end of the initialization operation.

Then, the initialization operation is completed, that is, the fixing roller pair 23a reaches the fixable temperature.
When it is determined that the second carriage has returned to the home position and that the toner density of the developing device 12 is within the allowable range, the trial copy is started.

In this test copy, a normal copy operation is performed while the first carriage is kept under the fixed scale 2a which is the home position.

That is, the exposure lamp 4 is the fixed scale 2
A white image is formed on the surface of the photosensitive drum 10 by being fixed under a and being guided to the photosensitive drum 10 via the optical system by the reflected light from the fixed scale 2a. In this case, the toner from the developing device 12 is not attached to the electrostatic latent image on the surface of the photoconductor drum 10, so that the toner is not wastefully consumed and the inside of the machine body is not contaminated by the toner.

On the other hand, in synchronization with this, the paper feed cassette 13
One of the uppermost sheets P from the inside is taken out by the delivery roller 15, and the sheet P passed through the sheet guide path 17 is delivered to the transfer section by the registration roller pair 19.

The image on the photosensitive drum 10 is transferred onto the surface of the paper P by the action of the transfer charger 20, and the paper P on which the image is transferred is separated by the charger 21.
Is electrostatically separated from the photoconductor drum 10 and is sent between the fixing roller pair 23a and the press roller 23b by the conveyor belt 22, and then the tray 25 outside the copying machine main body 1 by the paper discharge roller pair 24. Is discharged to. As a result,
This is the same as making a blank copy of a blank original on the uppermost paper in the paper feed cassette 13 through which the paper is passed.

During the trial copy, a message "Trial copy is in progress" is displayed on the message panel 30g. Also, a weight symbol mark may be displayed. In this way, when the trial copy is completed, a display indicating the ready state is displayed on the operation panel 30 and the operator waits for a key input. As described above, it is possible to prevent the image from being formed on the uppermost paper in the cassette.

That is, when the power is turned on, a blank copy is automatically made. This makes it possible to forcibly discharge the humid uppermost paper sheet, remove oil stains and dew condensation inside the machine body, and stabilize the machine body temperature along with this paper discharge. Therefore,
Immediately after the power is turned on, transfer omission, improper fixing,
It is possible to perform a good image forming operation on the first sheet after the power is turned on, without causing inconveniences such as stains, image defects, or paper curl.

In the above embodiment, the trial copy is automatically performed, but the present invention is not limited to this, and it is also possible to select, for example, by software or hardware.

Further, since blank copy is effective for cleaning dirt inside the machine body, not only one copy but also the number of sheets of paper for trial copy may be set arbitrarily.

Furthermore, the time until the power is turned on is measured,
It is also possible to perform the trial copy only when the power is not turned on for a long time or the temperature inside the machine is measured and the temperature is below a certain temperature. Of course, various modifications can be made without departing from the spirit of the invention.

[0031]

As described above in detail, according to the present invention, it is possible to provide an image forming apparatus capable of eliminating various inconveniences which appear on the image forming medium immediately after the power is turned on.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an outline of a copying machine according to an embodiment of the present invention.

FIG. 2 is a diagram similarly showing an example of an operation panel.

FIG. 3 is a flowchart similarly shown for explaining the operation.

[Explanation of symbols]

1 ... Copier main body, 2 ... Document table, 2a ... Fixed scale, 4
... exposure lamp, 10 ... photoreceptor drum, 11 ... charging charger, 12 ... developing device, 13 ... paper feed cassette, 15 ... delivery roller, 19 ... registration roller pair, 20 ... transfer charger,
22 ... Conveyor belt, 23a ... Fixing roller pair, 23b ... Press roller, 30 ... Operation panel.

Claims (3)

[Claims] 1. An image forming apparatus for forming an image on an image forming medium fed from a cassette, comprising a sheet passing means for forcibly feeding from the cassette after completion of an initialization operation. An image forming apparatus characterized by. 2. An image forming apparatus for forming an image on an image forming medium fed from a cassette, and a paper passing means for forcibly feeding paper from the cassette after completion of an initialization operation. An image forming apparatus comprising: a control unit that permits reception of a key input after the paper is fed by the paper unit. 3. An image forming apparatus for forming an image on an image forming medium fed from a cassette, wherein initialization means for performing an initialization operation, and when the initialization operation by the initialization means is completed, Taking-out means for taking out the image-forming medium from the cassette, paper-passing means for conveying the image-forming medium taken out by the taking-out means, and formation of a white background image on the image-forming medium conveyed by the paper-passing means An image forming apparatus comprising: an operation unit that performs the above operation; and a control unit that permits reception of a key input after the white background image is formed by the operation unit.