JPH0453957A - Positioning device for cylindrical drum - Google Patents

Abstract

PURPOSE:To prevent the rubbing contact of cylindrical drums and to prevent the flawing of the cylindrical drums even when the cylindrical drums are continuously transported by providing free moving means which freely move at least the gripping parts of gripping means in the transporting direction of the cylindrical drums. CONSTITUTION:The outside surfaces of the parts for connecting the cylindrical drums 1 to each other are gripped from the outside to correct steps. Then, the outside surfaces of the adjacent cylindrical drums 1 are positioned flush each other with good accuracy. In addition, the flawing of the entire part in the longitudinal direction of the cylindrical drums is obviated at the time of correcting the steps. The free moving means 15 which freely move at least the gripping parts 12 of the gripping means 10 in the transporting direction of the cylindrical drums 1 are provided. Even if the cylindrical drums 1 are already risen when the cylindrical drums 1 are gripped by the gripping parts 12, the gripping parts 12 are driven according to the rise thereof and, therefore, there is no rubbing contact to be generated if the positions of the gripping parts 12 of the gripping means 10 are fixed. The flawing on the outside surface of the cylindrical drums 1 is thus prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an apparatus for positioning a cylindrical drum when manufacturing an electrophotographic photosensitive member by coating the cylindrical drum with a photosensitive liquid.

[Conventional technology]

In manufacturing an organic photoconductor photosensitive drum, which is a photosensitive member used in an electrophotographic apparatus, a photosensitive coating liquid is applied to a cylindrical drum. In applying the coating, adjustment work is required to position slide holes and the like at predetermined positions around the cylindrical drum and to maintain a constant clearance between the two in the circumferential direction. In this case, since the required thickness of the coating layer is extremely thin, even if the cylindrical drum shifts by 0.1a+, it will cause a large deviation in the thickness of the coating layer as a whole in the circumferential direction.

It is a well-known fact that such deviations in the thickness of the coating layer cause various problems such as changes in the amount of charge, non-uniform sensitivity, and changes in residual potential in the circumferential direction of the cylindrical drum. Accurate positioning of the cylindrical drum is therefore extremely important.

Conventionally, this type of drum positioning device has been disclosed, for example, in Japanese Patent Application Laid-Open No. 60-50537 and Japanese Patent Application Laid-Open No. 60-955.
As in the technology described in Publication No. 46, position regulating rollers are provided around the drum in contact with each other, or a group of drive rollers provided in plurality in the conveyance direction of the drum are continuously applied to the coating head while in contact with the drum. It is known to adjust the relative positional relationship of the coating head with respect to the outer circumferential surface of the drum while supplying the coating head and moving the coating head in the horizontal direction via a trochanter.

[Problem to be solved by the invention]

However, all of the conventional devices perform positioning using a position regulating roller or a group of drive rollers, which has the disadvantage that the entire length of the cylindrical drum is damaged. It is well known that electrophotographic properties deteriorate if the drum is scratched.

On the other hand, with the device described in the latter publication, it is essential to adjust the position of the coating head in addition to regulating the drum position. However, if the coating head is made slidable, the position of the coating head relative to the drum is likely to shift, especially when the drum is It becomes difficult to maintain the coating head in a coaxial state at all times.

On the other hand, in each of the above examples, even if it is possible to position the two cylindrical drums being supplied to the coating head, it is impossible to align the axis of the subsequent cylindrical drum with the previous cylindrical drum. This is not possible and requires a separate means to align the coaxial center.

If the succeeding cylindrical drum does not closely match the preceding cylindrical drum, e.g. when raising the cylindrical drum,
When raised relative to the coating head via the subsequent cylindrical drum, the upper surface of the preceding cylindrical drum collides with the lower surface of the coating head, and a situation may occur in which it is not possible to enter the interior of the coating head. Furthermore, if the cylindrical drum group is raised in a state where there is a difference in level, the coating liquid will drip or run out at the difference in level, resulting in uneven coating thickness or uneven coating. Furthermore, with the technology described in the above publication,
Even if only the leading cylindrical drums are aligned, if the following cylindrical drums are installed in series and moved upwards with a difference in level, the leading cylindrical drums will have their fine edges tilted toward the coating head. Often supplied.

Therefore, as shown in FIG. 6, a step IA is formed on the inner surface of the end of the cylindrical drum 1, and each time a subsequent cylindrical drum 1 is connected, a spacer S having an outer diameter corresponding to the inner surface of the step IA is formed. It is possible to consider a means of eliminating the level difference between the preceding cylindrical drum 1 and the succeeding cylindrical drum 1 by installing the drum 1 internally.

However, although this embodiment requires a highly accurate spacer, a certain amount of clearance is required to insert the spacer into the step on the inner surface of the cylindrical drum, so there is a limit to the accuracy of correcting the step. Furthermore, it is necessary to insert and remove the spacer each time the spacer is installed in series and each time the application is completed, which requires a great deal of effort and manual labor, or requires two dedicated devices for insertion and removal. Furthermore, when removing and inserting the spacer, the bare spacer gets dirty with spray from the coating solution, and because the accuracy of level difference correction is inherently poor, the coating solution penetrates inside the spacer through the small gap created between the cylindrical drums, causing the spacer to become dirty. often gets dirty and requires cleaning at regular intervals.
Spacer management is extremely complicated.

The present inventors have found that in order to easily position the cylindrical drums without damaging the entire drum, it is preferable to grip the joints between the cylindrical drums.

However, this gripping method is suitable when the cylindrical drum is not being conveyed, but if the cylindrical drum is gripped while being conveyed continuously, the cylindrical drum may slide against the gripping surface of the gripping means. Contact may damage the outer surface of the cylindrical drum.

Therefore, the main object of the present invention is to prevent the above-mentioned sliding contact and damage to the cylindrical drum even when the cylindrical drum is continuously conveyed, while ensuring the above-mentioned advantages. be.

[Means to solve the problem]

The above-mentioned problem is a device that positions the cylindrical drum when it surrounds the outer peripheral surface of the cylindrical drum and applies a coating liquid to the outer peripheral surface of the cylindrical drum in the process of moving the cylindrical drum while being connected in the axial direction. a gripping means for gripping the outer surfaces of the joints between the cylindrical drums from the outside to correct the level difference; a transporting means for transporting the group of cylindrical drums; and at least the gripping portion of the gripping means is freely movable in the transporting direction of the cylindrical drums. This can be solved by providing a means of free movement.

[Effect]

In the present invention, the outer surface of the connecting portion between the cylindrical drums is gripped from the outside by the gripping means to correct the level difference.

Therefore, the spacer described above becomes unnecessary, and
No dedicated equipment or personnel are required to insert and remove the spacer. Furthermore, by gripping the outer surfaces of the joints between the cylindrical drums from the outside by the gripping means, the outer surfaces of adjacent cylindrical drums can be made to match with high accuracy.

Moreover, since only the connecting portion is sufficient for correcting the step difference, the entire length of the cylindrical drum is not damaged in the longitudinal direction as in the conventional publications.

Furthermore, since the free movement means for freely moving at least the gripping part of the gripping means in the transport direction of the cylindrical drum is provided, when the cylindrical drum is gripped by the gripping part, even if the cylindrical drum is raised, the As the gripping portion moves up, the gripping portion of the gripping means is free from sliding contact that occurs when the gripping portion is fixed in position, and as a result, damage to the outer surface of the cylindrical drum can be prevented.

〔Example〕

The present invention will be explained in more detail below with reference to Examples.

1 to 3 show an embodiment, in which 1 is, for example, a hollow cylindrical drum, which is transported upward while being chucked by a robot or the like. The conveying means 3 in the embodiment performs chucking using chucks 3A and 3B, and after chucking, the chuck 3A13B is raised by rotating the screws 3C and 3C using a rotary drive motor 3D. There is. Instead of this conveying means, it is also possible to use a conveying means configured to be raised by a cylinder or the like via the bottom surface of a cylindrical drum at the lower end.

Reference numeral 2 denotes an annular coating head for applying photosensitive liquid to the outer circumferential surface of the cylindrical drum l, which is fixed to the ground and continuously applies the photosensitive liquid from an outlet opening on the inner surface while the cylindrical drum 1 is rising. It is applied by discharging it.

The coating head as the coating means used in the present invention may have a basic structure that is arranged around the outer surface of the cylindrical drum 1 and applies a coating liquid to the outer surface of the cylindrical drum 1. No. 58-189061, Japanese Patent Publication No. 1983-
50537 and the like can be adopted as appropriate.

An example of this is shown in FIG. This coating head 2 is a slide hopper type coating head.

To explain this, in the coating head 2, a narrow coating liquid distribution slit 22 having a coating liquid outlet 21 opening on the lower side of the cylindrical drum is formed in the horizontal direction. This slit 22 communicates with a liquid reservoir header 23, and this liquid reservoir header 23
The photosensitive liquid is supplied by a pressure pump (not shown).

On the other hand, a liquid sliding surface 25 is formed below the coating liquid outlet 21 of the slit 22 so as to continuously slope downward and terminate at a dimension slightly larger than the outer dimension of the cylindrical drum 1. Further, a lip-like portion 26 is formed extending downward from the terminal end of the liquid slide surface 25.

When such a coating head 2 is used, in the process of pulling up the cylindrical drum 1, the photosensitive liquid is pushed out from the slit 22 and the coating liquid outlet 21, and is caused to flow down along the liquid sliding surface 25. The photosensitive liquid that has reached the lip-shaped portion 26 is removed from the lip-shaped portion 26.
It is applied to the outer surface of the cylindrical drum 1 to a thickness corresponding to the clearance between the cylindrical drum 1 and the cylindrical drum 1.

For this type of coating head 2, the cylindrical drum 111.
- A gripping means 10 is provided in order to concentrically supply the groups in a continuous manner with no difference in level.

The gripping means 10 of the embodiment includes a slide rail 11, a slide block 12 that constitutes a grip part fitted to the slide rail 11,
It has a press-and-separate cylinder 13 for pressing and retracting the drum against the outer surface of the cylindrical drum 1.

A plurality of slide blocks 12 can be provided, for example, four slide blocks 12 are provided at equal intervals in the circumferential direction as shown in FIG. can be provided.

Further, the slide rail 11 is supported on the pedestal 14 via springs 15 and 15, which constitute free movement means according to the present invention.

Furthermore, in order to determine the operation timing of the gripping means 10, a connecting portion detection means 4 is provided.

As the connecting portion detection means 4, it is possible to use an optical means that includes a light projector and a light receiver and detects that the brightness decreases at the connecting portion.

Under the device configured in this way, as shown in FIG. 1, the lower cylindrical drum IA is raised by the conveying means 3.3 together with the lower cylindrical drum 1.1 towards the position of the gripping means 1O110. When the slide block 12
．． 12 is in a position set back from the outer surface of the cylindrical drum.

When the ascent continues and the joint between the upper cylindrical drums 1.1 is detected by the joint detecting means 4, as shown in FIG. Since it is an integral multiple of the length of the drum 1, it is determined that the joint between the cylindrical drums IA and IB has reached the gripping means 10.10 position, and the approaching/separating cylinders 13.13 are operated.
The slide block 12.12 is advanced, thereby gripping the cylindrical drums IA, IB and correcting the difference in level between them.

At this time, when the group of cylindrical drums 1 rises, the springs 15, 15 are stretched by the rising force of the cylindrical drums 1, and the entire gripping means 10 rises. Therefore, sliding contact between the gripping surface of the slide block 2.12 and the outer surface of the cylindrical drum 1 is prevented. When the level difference is corrected, the slide block 12.12 immediately retreats and is raised again by the conveying means 3.3.

Such step correction is basically performed for each joint.

In addition, in the present invention, those skilled in the art can easily imagine other modifications of the gripping means, the means for free movement of the gripping portion of the gripping means, and the conveying means of the cylindrical drum itself.

For example, as the free movement means for the gripping part 12 of the gripping means 1o, only the gripping part 12 can be freely moved without being constructed by freely moving the entire gripping means 10 as in the above example. Further, as in the above example, instead of the spring 15, a cushioning material 15A such as rubber can be used.

That is, as shown in FIG. 4, a sliding wheel is attached to a lip groove-shaped holder 120a fixed to the tip of a slide block 12A. 20b is fixed in the vertical direction, and the piece 120c touches this.
At the same time, insert the cushioning material 1 into the holder 120a.
5A can also be interposed.

In this example, the contact piece 11c is a cylindrical drum IA.

When the joints between the IB and the IB are pressed and they rise, the upper cushioning material 15A contracts to prevent damage caused by sliding contact between the contact surface of the contact piece 11c and the outer surface of the cylindrical drum IA and IB. .

As the free movement means, an air action method can also be adopted.

As described above, the present invention is extremely effective as a coating device for manufacturing electrophotographic photoreceptors.

In this case, the photosensitive liquid may be one in which an inorganic photosensitive material such as zinc oxide or cadmium sulfide or an organic photosensitive material such as polyvinylcarbazole or trinitrofluorene is dispersed in a polymer binder. Furthermore, in recent years, in order to increase sensitivity and improve durability, functionally separated photosensitive layers in which a charge generation layer and a charge transport layer are laminated can also be used.

For example, the charge generation layer is made by dispersing azo pigments, quinone pigments, perylene pigments, phthalocyanine pigments, anthanthrone pigments, etc. in a polymeric binder such as polycarbonate, and the charge transport layer is made by dispersing polycyclic aromatic compounds, nitrogen-containing cyclic compounds, etc. It can be obtained by dispersing it in a molecular binder. The thickness of the charge generation layer is 0.01 to 10 μm, preferably 0.05 to 10 μm.
5 μm, and the thickness of the charge transport layer is preferably 5 to 30 μm.
It is μm.

The viscosity of the photosensitive liquid is in the range of 0.5 to 700 cp, preferably in the range of 1 to 500 cp.

Furthermore, examples of hollow drums for electrophotography include aluminum drum, stainless steel, and plastic on which a conductive layer is formed. Alternatively, an undercoat layer and a charge generation layer may be formed in advance.

〔Effect of the invention〕

As described above, the apparatus of the present invention provides advantages such as being able to prevent damage to the drum as a whole and damage caused by sliding contact, and also being able to reliably and easily correct steps.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of the positioning device according to the present invention in a state before the level difference is eliminated, FIG. 2 is a schematic diagram of the state in which the level difference has been eliminated, FIG. 3 is a plan view of an example of the arrangement of slide blocks, and FIG. The figure is a schematic view of another example of the structure of the free movement means, FIG. 5 is a longitudinal sectional view of an example of a coating head, and FIG. 6 is a longitudinal sectional view of a main part of an example in which a spacer is used to prevent a difference in level. DESCRIPTION OF SYMBOLS 1... Cylindrical drum, 2... Coating head, 3... Conveyance means, 4... Connecting part detection means, 5... Rotation drive motor, 10... Gripping means, 12... Slide Block (gripping part), 13... Separation cylinder 14...
Frame, 15-- Spring, 15A-- Cushioning material, (Gripping part). 20c...hit piece

Claims (1)

[Claims] (1) A device that positions the cylindrical drum when the cylindrical drum is moved while being connected in the axial direction, and the cylindrical drum is surrounded and coated with a coating liquid on the outer periphery of the cylindrical drum. ; a gripping means for gripping the outer surface of the connecting portion between the cylindrical drums from the outside to correct the level difference; a conveyance means for conveying the group of cylindrical drums; and at least a gripping portion of the gripping means is freely moved in the conveyance direction of the cylindrical drums. A cylindrical drum positioning device characterized by comprising a free movement means.