JPH07191505A - Image recorder - Google Patents

Abstract

PURPOSE:To eliminate the deterioration of image quality due to the temp. rising of an optical writing device by providing a control means for changing an image recording process condition in accordance with the detection output of the temp. rising by a temp. detecting means in order to obtain an optimum image. CONSTITUTION:Temp. information by the temp. detecting means is inputted to a process condition control means, and the surface potential of a photoreceptor as an electrophotographic process condition, or a developing bias is changed in detail by a control substrate 13 functioning as the control means so as to keep the image constant. That is, the surface potential of the photoreceptor is decided based on a voltage supplied by a power supply device 12 for supplying the voltage to an electrostatic charger 3. The temp. detection output by the temp. detecting means is inputted to the control substrate 13 in order to decide the impressed voltage, and also, a proper voltage capable of recovering the influence of the temp. rising is commanded to the power supply device 12 and the impressed voltage is changed, consequently, the surface potential is changed. And in the case of changing the developing bias value, the bias value is changed by changing the voltage impressed from the power supply device 12, corresponding to the change of the surface potential.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image recording apparatus applied to an image forming apparatus such as an electrophotographic apparatus, a facsimile and a printer.

[0002]

2. Description of the Related Art There is an image recording apparatus in which a charging device, an optical writing device, a developing device, a transfer device, a cleaning device, and a charge eliminating device are arranged so as to face a photoconductor and an image is recorded according to an image recording process.

[0003]

In the conventional image recording apparatus, when the image signal is written on the photoconductor by the optical writing device using the LED, the temperature of the LED device body rises due to the heat energy generated by the light emission.

With this temperature rise, GaAs, which is an LED element,
P has a reduced luminous efficiency and a reduced amount of light. Such a decrease in the amount of light is a serious problem, especially when a gradation image such as a graphical picture is being written as the image because the decrease in the amount of light appears immediately in accordance with the image quality.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an image recording apparatus capable of eliminating the deterioration of image quality due to the temperature rise of the optical writing device.

[0006]

In order to achieve the above object, the present invention has the following constitution.

(1). Facing the photoconductor, charging device,
In an image recording apparatus, in which an optical writing device, a developing device, a transfer device, a cleaning device, and a static eliminator are arranged, and which records an image according to an image recording process, a temperature detecting means for detecting a temperature rise of the optical writing device and the temperature detection means. According to the temperature rise detection output by the means, the control means changes the process condition of the image recording to obtain the optimum image (claim 1).

(2). In (1), the optical writing device is an LED array device, and the temperature detecting means is a temperature detecting sensor (claim 2).

(3). Facing the photoconductor, charging device,
In an image recording method device for arranging an optical writing device, a developing device, a transfer device, a cleaning device, and a static eliminator to record an image according to an image recording process, a temperature detecting means for detecting a temperature rise of the optical writing device, The writing device is provided with a cooling device for cooling the writing device and a control device for controlling the cooling device according to the output of the temperature detecting device (claim 3).

(4). In (1) or (3), the temperature detecting means is composed of one or more temperature detecting sensors (claim 4).

[0011]

According to the first and second aspects of the present invention, the image recording process condition is appropriately changed by the control means according to the temperature information of the temperature detecting means for detecting the temperature of the optical writing device, and the image formation is performed by the temperature rise of the optical writing device. Is controlled so that the influence of is reduced.

According to the third aspect of the present invention, the temperature of the optical writing device is controlled within the temperature range in which the cooling device is driven by the control device and does not affect the image formation according to the temperature information from the temperature detection device.

[0013]

[Example] 1. Image Recording Apparatus Suitable for Implementing the Present Invention FIG. 5 shows an example of an image recording apparatus suitable for implementing the present invention. This image recording apparatus is a transfer type color image recording apparatus and has photoreceptors 2a, 2b, 2c and 2d for forming images of cyan, magenta, yellow and black colors necessary for obtaining a full color image. .

Around the photoconductor 2a, a charging device 3, an optical writing device 4, a developing device 5, a transfer device 6, a cleaning device 7, a charge eliminating device 8 and the like are arranged in opposition to the photoconductor 2a. The other photoconductors are also arranged in the same device, but the explanation is omitted because it is complicated.

A transfer belt 10 is provided so as to pass between each photoconductor and the transfer device. Each image information obtained by color-separating a color original image is carried as a latent image on each photoconductor through each optical writing device, then visualized by a developing device, and set on the transfer belt 10. Are sequentially transferred onto the respective photoconductors, and a full-color toner image is formed on the transfer paper.

This full-color toner image is transferred onto the transfer paper sent from the paper feed cassette 1. The transfer paper onto which the full-color toner image has been transferred is fixed while passing through the fixing device 9 and is discharged to the paper discharge tray.

In FIG. 5, reference numeral 12 is a power supply unit of the image recording apparatus, and reference numeral 13 is a control board for controlling the process of the image recording apparatus.

2. Description corresponding to claims 1 and 2 FIG. 1 shows an embodiment of the invention of claims 1 and 2. In FIG. 1, reference numeral 20 indicates a temperature detecting means, which is a temperature detecting sensor for detecting the temperature of an LED array as an optical writing device.

The temperature information obtained by this temperature detecting means is shown in FIG.
When the temperature rise is input to the control means of the process means indicated by reference numeral 21 and the light quantity of the optical writing device is decreased, the surface of the photoconductor which is a process condition of image recording is compensated for so as to compensate for this light quantity decrease. The electric potential or the developing bias of the developing device is gradually changed to make the image constant.

The control means 21 shown in FIG. 1 is specifically shown in FIG.
The control board 13 is applicable. Control board 1 as control means
Reference numeral 3 controls the surface potential of the photoconductor or the developing bias, which is a process condition for electrophotography, to be changed one by one to control the image to be constant.

The surface potential of the photosensitive member is determined by the supply voltage of the power supply device 12 which supplies the voltage to the charging device 3. In order to determine this applied voltage, the temperature detection output of the temperature detection means 20 is input to the control board 13, and the power supply device 12 is instructed to an appropriate voltage that can avoid the influence of the temperature rise, and the applied voltage is changed. As a result, the surface potential is changed.

When the developing bias value is changed, it is also changed by changing the voltage from the power supply device 12 in accordance with the change of the surface potential.

3. 2. Description of Claim 3 As shown in FIG. 2, the temperature detecting means 20 for detecting a temperature rise of the optical writing device 4 is provided, which is the same as the example according to Claims 1, 2 and 4. .

In this example, the cooling device 23 is driven through the control means 22 of the cooling means based on the temperature detection result of the temperature detection means 20 so that the increased temperature is returned to the normal temperature. Prevent deterioration.

The temperature detecting means 20 detects the temperature rise of the LED main body which constitutes the optical writing device 4, and inputs the output to the control means 22. The control means 22 drives the cooling fan 23-1 shown in FIG. 4 as an example of the cooling device 22 so that the increased temperature of the light detection means returns to normal.

That is, this control system constitutes a feedback control system, and controls the air volume of the cooling fan so that the temperature of the LED becomes constant. It is the control means 22, and specifically the control board 13, that controls this control.

In FIG. 4, the arrow indicates the cooling fine 23-.
1 shows the wind flow. Reference numeral 100a indicates the front surface of the machine body, and reference numeral 100b indicates the back surface of the machine body.

4. Description Corresponding to Claim 4 As shown in FIG. 3A, the optical writing device 4 includes a lens 4-2, an LED chip mounting substrate 4-3, and a cover 4-4 which are assembled to the base body 4-1. , Radiating fins 4-5
Etc. These have a length corresponding to the width of the photoconductor in the direction of penetrating the paper surface, that is, in the axial longitudinal direction of the photoconductor.

As shown in FIG. 3B, the LED chip mounting board 4-3 is provided with an LED chip 4-3-1.
Temperature detection sensors forming the temperature detection means 20 are provided at two locations in the longitudinal direction.

When one temperature detecting sensor is provided, the temperature detecting sensor is provided at a substantially central position of the photoconductor width, and when a plurality of temperature detecting sensors are provided, the temperature detecting sensors are provided at equal intervals in the photoconductor width.

[0031]

According to the present invention, it is possible to provide an image recording apparatus capable of eliminating the deterioration of the image quality due to the temperature rise of the optical writing apparatus.

[Brief description of drawings]

FIG. 1 is a block diagram illustrating a control system of the invention corresponding to claim 1. FIG.

FIG. 2 is a block diagram illustrating a control system of the invention corresponding to claim 3;

FIG. 3 is an explanatory diagram of an optical writing unit.

FIG. 4 is a diagram illustrating an arrangement of cooling devices according to a third aspect of the invention.

FIG. 5 is a sectional view of the image recording apparatus.

[Explanation of symbols]

 20 temperature detecting means 21 control means

Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location G03G 15/04 21/20

Claims (4)

[Claims] 1. An image recording apparatus for recording an image according to an image recording process, comprising a charging device, an optical writing device, a developing device, a transfer device, a cleaning device, and a charge eliminating device, which are opposed to a photoconductor. Image recording characterized by having temperature detection means for detecting a temperature rise of the apparatus and control means for changing the process condition of the image recording in order to obtain an optimum image according to the temperature rise detection output by the temperature detection means. apparatus. 2. The optical writing device according to claim 1, wherein the optical writing device is LE.
An image recording apparatus, which is a D array apparatus, wherein the temperature detecting means is a temperature detecting sensor. 3. An image recording apparatus for recording an image according to an image recording process, wherein a charging device, an optical writing device, a developing device, a transfer device, a cleaning device and a charge eliminating device are arranged facing a photoconductor. An image recording device comprising: a temperature detection unit that detects a temperature rise of the device; a cooling device that cools the optical writing device; and a control unit that controls the cooling device according to the output of the temperature detection unit. apparatus. 4. An image recording apparatus according to claim 1 or 3, wherein the temperature detecting means comprises one or more temperature rise detecting sensors.