JP2003043757A - Electrophotographic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem that the life of a contact type temperature detecting member is shortened because the contact part thereof is worn, or temperature can not be measured accurately because of the adhesion of dust to the surface of a measuring member, and further a printed matter is soiled because the contact part of a photoreceptor is also worn and damaged in the case of repeating rotation in a method in which the contact type temperature detecting member is attached to the surface of the photoreceptor, and also an optical temperature detecting member is soiled by the repeated rotation and temperature is changed with the lapse of time and reliability on the measured temperature is lowered in a method in which the optical temperature detecting member is attached to a position where it does not come into contact with a photoreceptor drum. SOLUTION: The temperature of the photoreceptor being a rotating body is not directly but indirectly measured by attaching the contact type temperature detecting member for detecting the temperature of a member fixed near to the photoreceptor.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a charger for charging a photoconductor, an optical device for exposing a charged photoconductor to form an electrostatic latent image on the photoconductor, and a photoconductor formed on the photoconductor. The present invention relates to the temperature measurement of a photosensitive member of an electrophotographic apparatus having a developing device for developing an electrostatic latent image and a transfer device for transferring the developed developed image onto a sheet.

[0002]

2. Description of the Related Art In the prior art, a method of mounting a contact type temperature detecting member on the surface of a photoconductor or facing a photoconductor,
The temperature of the photoconductor is measured by a method in which an optical temperature detecting member is attached to a position where the photoconductor does not come into contact with the photoconductor.

[0003]

The temperature of the photosensitive member in the electrophotographic apparatus affects the charging characteristics of the photosensitive member and the sensitivity of the photosensitive member to the laser light emitted from the optical device, and it is important to influence the image quality of the printed result. Since it is a parameter, the conventional method is to stabilize the temperature of the photoconductor, or to control the conditions of each part of the optical device, the developing device, etc. according to the temperature of the photoconductor. The temperature of the photoconductor needs to be detected stably and reliably in the above control. However, when printing on paper, the photoconductor rotates while performing the steps of charging, exposing, developing, transferring, and cleaning at a constant speed, and in the method of attaching the temperature detection member to the position in contact with the photoconductor of the related art, Since the temperature measuring member is in contact with the photoconductor, the contact part of the temperature measuring member may wear and shorten the life of the temperature detecting member, or stains on the surface of the measuring member may prevent accurate temperature measurement. . Further, the contact portion of the photoconductor was also worn and scratched, and the print was stained. In addition, in the method of mounting the optical temperature detecting member at a position where it does not come into contact with the photosensitive drum, the detection surface of the optical temperature detecting member becomes soiled due to dirt due to toner scattering, etc., which occurs when the rotation is repeated, and the measured temperature does not change over time. Change, which reduced the reliability of temperature measurement.

[0004]

SUMMARY OF THE INVENTION The present invention is intended to stably detect the temperature of a photoconductor without damaging the photoconductor and being not changed with time. This object is achieved by attaching a contact-type temperature detection member that detects the temperature of the fixed member to a fixed member near the photoconductor.

[0005]

DETAILED DESCRIPTION OF THE INVENTION The present invention will be described below with reference to the accompanying drawings. FIG. 1 shows a charger 2 for charging a photoconductor 1, an optical device 3 for exposing a charged photoconductor to form an electrostatic latent image on the photoconductor, and an electrostatic latent image formed on the photoconductor. A light-shielding cover 4 that covers the photoconductor that blocks external light other than optical so as not to disturb the light, a developing device 5 that develops the electrostatic latent image formed on the photoconductor, and a developed image on the paper 7. FIG. 3 is a sectional view of an electrophotographic apparatus having a transfer device 6 for copying. The light shielding cover 4 is fixed within a distance of 30 mm perpendicular to the electrostatic latent image forming surface of the photoconductor. A contact-type temperature detecting member 9 for detecting the temperature of the light shielding cover 4 was attached to the light shielding cover 4. In the electrophotographic apparatus,
The results of measuring the temperatures of the photosensitive member 1 and the light-shielding cover 4 during printing are shown in FIG. In FIG. 2, the temperatures of the photoconductor 1 and the light-shielding cover 4 show a linear correlation, and the temperatures of the light-shielding cover 4 and the photoconductor 1 can be approximated by a linear expression. Instead of measuring the temperature of
By indirectly measuring the temperature of the light shielding cover 4, the temperature of the photoconductor 1 can be sensed without actually measuring the temperature of the photoconductor 1.

[0006]

Since the temperature of the fixed member in the vicinity of the photosensitive member correlates with the temperature of the photosensitive member, the temperature of the rotating photosensitive member is not directly measured but the fixing member is indirectly fixed. The temperature of the photoconductor can be detected by measuring the temperature. In addition, the fixing member is fixed unlike the photoconductor which is a rotating body, and the contact type temperature detecting member attached to the fixing member is not worn or has a surface in contact with the photoconductor. Since there is no wear and the contact surface of the contact type temperature detecting member is not contaminated, the measured value of the temperature of the fixing member is stable, and the temperature detecting member can sense the temperature of the photoconductor without being changed with time. .

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing an embodiment of the present invention.

FIG. 2 is a graph showing a correlation between temperatures of a photoconductor and a light-shielding cover that covers the photoconductor.

[Explanation of symbols]

1 is a photoconductor, 2 is a charger, 3 is an optical device, 4 is a light-shielding cover, 5 is a developing device, 6 is a transfer device, 7 is printing paper, 8 is a cleaner, and 9 is a temperature detecting member.

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Claims (2)

[Claims] 1. A charging device for charging a photoreceptor, comprising:
An optical device that exposes a charged photoconductor to an electrostatic latent image on the photoconductor, a developing device that develops the electrostatic latent image formed on the photoconductor, and a developed image on a paper sheet. And a temperature detection member for measuring the temperature of the photoconductor,
In an electrophotographic device that measures the temperature of the photoconductor and performs feedback control to change the partial condition or multi-part condition of the above device to stabilize the print quality, depending on the photoconductor temperature,
An electronic device characterized in that a contact-type temperature detecting member for detecting the temperature of the fixing member is attached to the fixing member in a region within a distance of 30 mm perpendicular to the electrostatic latent image forming surface of the photosensitive member. Photographic equipment. 2. A vertical distance 3 from the electrostatic latent image forming surface of the photoconductor.
The electrophotographic apparatus, wherein a contact-type temperature detecting member for detecting the temperature of the fixing member is attached to the fixing member having a part of the fixing member in an area within 0 mm.