JPS62229264A - Color copying machine - Google Patents

Abstract

PURPOSE:To eliminate the positional deviation of transfer images due to the disturbance of parallelism of drums and transfer belt by providing a positioning adjustment mechanism for each drum for the purpose of ensuring the parallelism between each photosensitive drum and a transfer belt driving roll shaft. CONSTITUTION:A face plate 25 is provided with attaching and fixing holes 26 and 27 to a front plate and the required number of holes 33 having a diameter larger than that of photosensitive body attaching shafts and adjusting member attaching tapped holes 34, and an adjusting member 29 superposedly fixed on the hole 33 is provided with a photosensitive body positioning hole 28 having the same diameter as the photosensitive body shaft and attaching holes 30. After reference shafts 31 and face plate positioning shafts 32 are attached to photosensitive body attaching holes of a rear plate 21, the face plate 25 is put on the rear plate 21 based on shafts 32, and reference shafts 31 passing through holes 33 are used to fix positioning adjustment members 29 to the face plate 25 through holes 30 and 34 by screws. When the face plate 25 is detached from the rear plate 21 thereafter, positions of photosensitive body attaching holes of the rear plate 21 coincide with photosensitive body positioning holes 28 of positioning adjustment members 29 attached to the face plate 25, and thus, the parallelism of plural photosensitive bodies is ensured.

Description

[Detailed Description of the Invention] [Technical Field] The present invention relates to a color copying machine using a plurality of photoreceptors and a transfer belt, and can also be applied to a color copying machine and a facsimile machine using an electrophotographic process. It is.

[Prior Art] Many color copying machines that use multiple photoreceptors and transfer belts have been proposed, but generally the position of each photoreceptor is determined by the rear plate and front face plate of the main body. As shown in FIG. 3, the inclination θ of the photoreceptor 9 appears twice (2θ) on the transfer paper P, so when the images of each photoreceptor are superimposed on the transfer paper, one color will be blurred. Therefore, in order to regulate the position of each photoreceptor, strict accuracy is required for both the hole positions of the rear plate and the face plate. One possible adjustment method is to tilt the exposure means so that there is no inclination on the transfer paper according to the inclination of the photoreceptor, but with this method, it is necessary to adjust the exposure means according to the inclination of the photoreceptor for each recording device. However, there are disadvantages in that it takes a lot of time and effort, and the adjustment cost is also high.

To further explain the conventional apparatus, FIG. 2 is a sectional view showing a conventionally used color copying machine to which the present invention can be applied. Color copying is possible by forming images in each of the four colors (Similarly C), black (Similarly BkJ) and then transferring and superimposing them.

The copying machine has a scanner part 1, a processing part 2. In the printer part 3 and the scanner part l, the document is illuminated with a fluorescent lamp, the reflected light is reflected by a mirror, and the image forming lens 4
The light enters the dichroic prism 5, where the light of three wavelengths, red (R), clean (G), and blue (
The light is separated by the BJ and enters the CCD (7R, 7G, 78).

The light incident on the CCD (7R17G, 7B) is converted into a digital signal and sent to the image processing section 2.

The image processing unit 2 performs necessary processing to obtain recording color information such as black (Bk), yellow (Y), magenta (M),
The signal is converted into a recording activation signal for cyan (C). The converted signal is sent to the printer section 2 (7) L/-f-light output bag @8 (88k, 8v, 8M, 8C),
Based on the signal, the laser beam emitted from the laser beam emitting device, which is the exposure means, is applied to the photoreceptor 9 (98k, 9v, 9M).
, 9c) Form an image. Note that the photoreceptor 9 is charged with a charged Nayaja 10 (lOBk, 10Y, IOM, l
0c) and is uniformly charged. next.

The latent image on the second photoconductor is transferred to the developing base 11 (llBk, IIY
, IIM, 11C), respectively.
Transfer charger 12 (128, 12”/, 12
M, 12 (transferred to transfer paper by J.

The transfer paper is sent out from the cassette by the paper feed roller 13,
After the timing is adjusted by the register 1-roller 14, the sheet is conveyed by the transfer bells 1 to 15, the image is transferred at each transfer position, the sheet is fixed by the fixing roller 16, and the sheet is discharged by the sheet discharge roller 17.

Next, to explain the color blur caused by the tilt of the photoreceptor,
As shown in Figure 3, if one side of the photoconductor is shifted by Δχ with respect to the ideal photoconductor position (assuming the inclination of the photoconductor at this time is 8), then in this state the laser beam will be applied to the transfer paper. P
If a line is made on the photoconductor 9 at 90 degrees with respect to the direction of movement, the inclination of the transferred image will be 2θ (twice the inclination of the photoconductor)
Next door.

As a result, the line slippage becomes 2Δχ. When images are transferred from four photoreceptors in such a state, the inclinations of each photoreceptor do not match, so the lines of images formed and superimposed with the photoreceptors tilted do not overlap.

FIG. 4 shows a conventional example of positioning a photoreceptor drum, in which photoreceptor mounting shafts 22 (228), 22Y, 22M, and 22 (J) are attached to the rear plate 21 of the main body. The belt drive roller (8) is rotatably attached to the rear side plate 21 and the front side plate 23 via bearings 19, 20.Furthermore, on the front side plate 23, a face plate 25 for positioning the axis for mounting the photoconductor is positioned and fixed. The face plate 25 has face plate fixing holes 26, 27 and photoconductor positioning holes 28 (288, 28Y, 28M, 28).
C) is provided and after mounting a photoreceptor on each shaft 22.

The face plate 25 is attached and the position of each photoreceptor is determined.

In this case, due to variations in the positions of the holes and shafts, the photoreceptors are not parallel to each other, and therefore, the superimposed transferred images are likely to be misaligned or have uneven color.

[Purpose] The present invention aims to improve the above-mentioned drawbacks of the conventional apparatus, and in order to reliably guarantee the parallelism of each photoreceptor drum and the transfer belt drive roller axis, a positioning adjustment mechanism for each drum is provided. By adopting a configuration in which each drum,
This is intended to eliminate misalignment of transferred images due to imbalance in the parallelism of the transfer belt.

[composition] In the present invention, one side plate is provided with a photoreceptor or a photoreceptor.

One end of the drive roller shaft of the photoreceptor and the transfer belt is supported, and a face plate is fixed to the other side plate, on which adjusting members that support the other end of each of the shafts are individually adjustable. This is an attempt to ensure the parallelism of the photoreceptor axes, etc. in a color copying machine equipped with #i number of photoreceptors, and to prevent one color shift from occurring. 6 FIG. 1 shows a rear side plate in a color copying machine according to the present invention, and
It is a perspective view which shows the relationship between the face plate attached to the front side plate corresponding to this, and the adjustment member provided so as to be adjustable.

As shown in FIG. 1, the face plate 25 according to this embodiment requires holes 26 and 27 for fixing the attachment to the front side plate, a hole 33 with a diameter larger than the photoconductor attachment shaft, and a screw hole 34 for attaching the adjustment member. The adjustment member 29, which is superimposed and fixed on the hole 33, is provided with a photoreceptor positioning hole 28 and a mounting hole 30 having the same diameter as the photoreceptor axis.

After attaching the reference shaft 31 and the face plate positioning shaft 32 to the photoreceptor mounting hole of the rear plate 21, the face plate 25 is placed on the rear plate 21 with the shaft 32 as a reference. Then, the positioning adjustment member 2g is fixed to the face plate 25 using the reference shaft 31 through the hole 33 with a screw, and then the face plate 25 is removed from the rear plate 21. The position of the body mounting hole and the photoreceptor positioning hole' of the positioning adjustment member 29 attached to the face plate,! 8 positions coincide, and the parallelism of 1t1 several photoreceptors is guaranteed.

In addition, in this embodiment, whether the reference shaft 31 was used during assembly or
The photoreceptor mounting shaft may be used as is.

Further, in the embodiment, only the parallel alignment of the plurality of photoreceptor mounting shafts is performed, or in addition to this, the parallel alignment of the transfer belt driving roller may be performed simultaneously.

effect] As explained below, according to the present invention.

(1) Since the parallelism between each photoreceptor (including the belt when driving rollers at the same time) is ensured, there is no installation error.

(!) There is no need to make parts accurate.

+3+ Accuracy is guaranteed when assembling at the component level.

It requires less assembly time and reduces adjustment costs.

It has this effect.

[Brief explanation of drawings]

FIG. 1 shows a rear plate in a color copying machine according to the present invention,
A perspective view showing the relationship between a face plate attached to the corresponding front side plate and an adjustment member provided on this face plate so as to be able to adjust the WI4, and FIG. 2 is a conventionally used color copy to which the present invention is applicable. 3 is a plan view showing the relationship between the transfer paper and the photoreceptor drum, and FIG. 4 is a perspective view showing the relationship between the front and rear side plates and the face plate showing a conventional example of positioning the photoreceptor tram. be. 1... Part of the scanner, 2... Processing section, ;U...
Printer section, 8... Rape-emission device (exposure means). 9... Photosensitive drum, 10... Charger. 11... Developing device, 12... Transfer charger, 15... Transfer bell l-, 19, 20... Bearing, 2
1... Rear side plate, 22... Photoconductor mounting shaft,
23...Front side plate, 24...Positioning and fixing shaft. z5... Face plate, 26.27... Mounting fixing hole. 28...Photoconductor positioning hole. 29...&l! ! Member, 30...hole. 31...Reference shaft (photoconductor mounting shaft), 3...Face plate positioning shaft, :33...Hole larger than the photoconductor mounting shaft, P...Transfer paper.

Claims (2)

[Claims] (1) A photoreceptor, a charger that uniformly charges the surface of the photoreceptor, an exposure unit that projects light onto the photoreceptor according to recorded information, a developer that converts an electrostatic latent image formed by exposure into a head image, and In a color copying machine, in which a plurality of recording devices each consisting of a transfer means for transferring a developed image onto a transfer paper are arranged, and the transfer paper is conveyed by a transfer belt that electrostatically attracts the paper, one side plate has a photoreceptor shaft or One end of the photoconductor shaft and the drive roller shaft of the transfer belt are supported, and a face plate is fixed to the other side plate, on which adjustment members for supporting the other end of each shaft are individually adjustable. A color copying machine with the following features: (2) Fit each shaft into the support hole that supports the photoreceptor shaft of one side plate or the drive roller shaft of the transfer belt, and fit the support hole and shaft into the face plate attached to the other side plate. 2. A color copying machine according to claim 1, further comprising an adjusting member which is adjustable so as to be inserted therethrough and positioned and fixed.