JPS5949573A - Inspecting device of photoreceptor for electrophotography - Google Patents

Abstract

PURPOSE:To detect quickly, easily, and accurately the abnormality of a photosensitive layer which is a cause of image defects, by providing a means for electrostatic charging the surface of a cylindrical photoreceptor, a movable potential detecting probe, and destaticizing means. CONSTITUTION:A cylindrical photoreceptor 1 to be inspected is supported and rotated by rolls 2. An electrostatic charging 3, a potential detecting probe 4, and a destaticizing lamp 6 are provided near the surface of the photoreceptor 1. The surface of the photoreceptor 1 electrostatic charged by the electrostatic charger 3 is scanned from one end to the other by the probe 4 to measure the potential. The detection potential of the probe 4 is recorded in order at a certain pitch through a potentiometer 7 by a pen recorder 8. This potential is indicated with a waveform 31 and is indicated on a chart as a potential abnormal waveform 32. The degree of the abnormality is detected by a height (h) of the abnormal waveform 32. This defect is detected beforehand to remove the photoreceptor 1 which generates image defects.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a photoreceptor inspection device for detecting abnormalities in a photosensitive layer that causes defects on an image in an electrophotographic photoreceptor.

In order to detect abnormalities in the photosensitive layer, there are two methods: indirect means to detect surface defects visually or using an optical device, and direct means to detect surface defects by installing them in the copying machine and obtaining copied images under practical conditions. A method of visually evaluating is known. The former method is commonly used in order not to damage the commercial value of the photoreceptor, but it is difficult to strictly clarify the correlation between the degree of image defects and the size, shape, etc. of surface defects. and when inspecting, e.g. visually,
This method has drawbacks such as individual differences among examiners and difficulty in making judgments with good reproducibility, making it an incomplete method as a means of confirming image quality. On the other hand, in the latter case, the surface of the photoreceptor is damaged and contaminated by the photo processing process, resulting in a significant loss of commercial value, and the mounting work on the copying machine is as tedious as general line work, so it should generally be avoided as much as possible. This is the content of the construction.

SUMMARY OF THE INVENTION An object of the present invention is to provide an electrophotographic photoreceptor inspection apparatus that eliminates the drawbacks of these methods and can simply, quickly, and accurately find abnormalities in the photosensitive layer that cause image defects.

This purpose is to provide an inspection device that includes a drive means that supports a cylindrical photoreceptor at its end and rotates it around its axis, and a drive means that supports the cylindrical photoreceptor at its end and rotates the photoreceptor M'/ in the axial direction of the photoreceptor, facing the surface of the photoreceptor M'/ of the rotating photoreceptor. Charger i1 Probe for detecting micro-area potential that is movable in the axial direction of the photoreceptor, close to and opposite the surface of the photosensitive layer, and charger i1 that charges the entire length of the photoreceptor; This is achieved by comprising a static eliminating means.

Embodiments of the present invention will be described below with reference to the drawings.

The cylindrical photoreceptor to be inspected is supported by a rotation transmission roller 2 to prevent shaft wobbling during rotation. This support may be a part of the end of the photoreceptor 1 where a photoreceptor layer is not normally provided and which is allowed to come in contact with foreign matter, or a pier machined to fit parts such as a 7 flange for supporting the photoreceptor. However, the commercial value of the photoreceptor will not be compromised. A charger 6 is disposed close to the surface of the photosensitive layer of the photoreceptor 1, and a potential detection probe 4 is disposed behind the charger 6 in the rotational direction. ? )5: tj! As vessel 5,
A frame charger commonly used in copying machines is used, and the probe 4 is a commercially available high-resolution type, for example, 1009 manufactured by Mon" CM Onl" Oe).
An E-type probe or the like can be used.

It is preferable that the distance P between the probe 4 and the surface of the photoreceptor 1 is as small as possible, but due to constraints on mechanical precision, it is practically set to 0.1 to 1 tntn, so that the entire surface of the photosensitive layer can be scanned. It is attached to a support 5 that is movable in the axial direction of the photoreceptor 1 (in FIG. 1, in a direction perpendicular to the plane of the figure). Further, at the rear in the rotational direction, the photosensitive layer is irradiated over its entire length by a static eliminating lamp B, and the surface potential of the charger 1 before charging is neutralized to approximately zero. Note that an electrical static eliminator may be used or used in combination for static neutralization. Then, the rotating photoconductor is charged to a predetermined level by a charger 3, and the surface potential is measured while scanning the photoconductor 1 with the probe 4 from one end to the other end. That is, as shown in FIG. 2, the surface potential when the entire length 21 of the photoreceptor 1 is scanned along a scanning locus 23 by the probe 4 moving in the direction of the arrow 22 is measured at a constant level by the pen recorder 8 via the electrometer 7. When arranged in order of pitch, it becomes as shown in Fig. 3. The potential measured by scanning the probe 4 during one rotation of the photoreceptor is shown by a waveform 31 spread out along the circumference. For example, photoreceptor 1 in FIG.
Regarding the abnormality 24 existing on the surface of
The degree of abnormality can be known from the magnitude h of the potential abnormality.

By knowing the relationship between this potential and image defects in advance and setting a potential standard that corresponds to the image standard, it becomes possible to detect and determine image defects based on the potential.

As described above, the electrophotographic photoreceptor inspection equipment according to the present invention uses a high-resolution electrometer and a probe to detect abnormalities in the photosensitive layer that cause image defects as abnormalities in the surface potential, and uses a sonobu rope. It is possible to scan the probe in the axial direction of the photoconductor while supporting the photoconductor at its end and rotating it so as to bring the probe close to the surface of the photoconductor layer, maintain the spacing with high precision, and not impair the commercial value of the photoconductor. With this structure, abnormalities in the photosensitive layer can be detected quickly and reproducibly in response to image defects, and photoreceptors that cause image defects can be reliably prevented from being put on the market, so the effects obtained are extremely large.

[Brief explanation of the drawing]

FIG. 1 is a layout diagram showing an embodiment of the present invention, FIG. 2 is a front view of a photoreceptor conceptually showing inspection by inspection equipment according to the present invention, and FIG. 3 is a diagram showing a measurement chart thereof. be. 1: Photoreceptor, 2: Rotation transmission roller, 3: Charger, 4
: Potential detection probe, 6: Static elimination lamp.

Claims (1)

[Claims] 1) A driving means that supports a cylindrical photoreceptor at its end and rotates it around its axis; and a charger that opposes the surface of the photosensitive layer of the rotating photoreceptor and charges the entire length of the photoreceptor in the axial direction. , comprising: a micro-area potential detection probe that faces the surface of the photosensitive layer and is movable in the axial direction of the photosensitive member; and a static eliminating means that faces the surface of the photosensitive layer and eliminates static electricity over the entire axial length of the photosensitive member. An inspection device for electrophotographic photoreceptors.