JP2004213040A - Image exposure means assembly method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an assembly method in which an optical system for an image exposure can be secured at a focusing position without a controlling mechanism or a mounting member. <P>SOLUTION: This is an assembly method of an image exposure means which is used for a color image forming device in which a plurality of charged means, image exposure means and developing means are provided respectively at the periphery of an image forming body, and after a plurality of toner images are superposed and formed on the image forming body in one rotation of the image forming body, they are copied onto a copying material in a lump. This method has a step of holding the image exposure means position-controllably and a controlling device to support a supporting member which installs the image exposure means and a CCD where an image formation surface is set at the position corresponding to the image formation body surface is used, and moving the image exposure means in vertical direction of the CCD surface and its position so that the focus of the image exposure means focuses the CCD surface, and a step of securing the position controlled image exposure means on the supporting member via adhesive with low hardening shrinkage characteristics. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

  The present invention relates to a method of assembling an image exposing unit used in a color image forming apparatus for forming a color image by superimposing a plurality of toner images on a peripheral surface of an image forming body, and in particular, an optical system as an image exposing unit and a light source. The present invention relates to a method of assembling image exposure means used in a digital color image forming apparatus using an exposure optical system in which the image exposure means is integrated.

  As a method of forming a multi-color image, a single-color toner image formed on a photoconductor is superimposed on an intermediate transfer body, etc., each including the same number of photoconductors, chargers, developing devices, and the like as required for the image. (A), a device for forming a color image by repeating charging, image exposure and development for each color by rotating a single photoconductor a plurality of times, or a single photoconductor, An apparatus (C) for forming a color image by sequentially performing charging, image exposure, and development for each color within rotation is known.

  However, the above-mentioned device (A) has a drawback that the volume of the device is increased due to the need for a plurality of photoconductors and intermediate transfer members, while the device (B) requires only one charging means, image exposure means and photoconductor. Therefore, although the volume is reduced, there is a restriction that the size of an image to be formed is limited to the surface area of the photoreceptor or less. There are many advantages such as no limitation on size and high-speed printing.

  However, the apparatus (C) is capable of positioning the optical system with high precision so that all of the plurality of image exposure means are accurately coupled to the surface of the photoreceptor, and guaranteeing the resist accuracy of the image exposure, that is, the image exposure to be superimposed. It is necessary that the image exposure position always coincides with the image plane in a correct and synchronized manner.

  An object of the present invention is to provide a color image forming apparatus in which the image exposure means can be adjusted and fixed to the photoreceptor surface with high precision and easy operation as a result of solving and improving this point. is there.

  Further, the present invention solves this problem and as a result, as a result, assembling of the image exposure means used in the color image forming apparatus which enables the image exposure means to be adjusted and fixed to the photoreceptor surface with high precision and easy operation. It is intended to provide a method.

The above purpose is
1) A plurality of charging means, image exposing means, and developing means are provided around the image forming body, and a plurality of toner images are superimposed on the image forming body during one rotation of the image forming body, and then transferred. A method of assembling an image exposure unit used in a color image forming apparatus that collectively transfers to a material,
Using an adjustment device that holds the image exposure unit in a position-adjustable manner, and that supports a support member to which the image exposure unit is attached, and a CCD having an imaging surface set at a position corresponding to the image forming body surface,
Moving the image exposure means in the vertical direction of the CCD surface to adjust the position of the image exposure means so that the focus of the image exposure means is focused on the CCD surface; and Fixing on the supporting member via a non-conductive adhesive,
2) A plurality of charging units, image exposing units, and developing units are provided around the image forming body, and a plurality of toner images are superimposed on the image forming body during one rotation of the image forming body, and then transferred. A method of assembling an image exposure unit used in a color image forming apparatus that collectively transfers to a material,
Arranging a CCD having an imaging surface set at a position corresponding to the image forming body surface on a support member to which the image exposure unit is attached;
Moving the image exposure means in the vertical direction of the CCD surface to adjust the position of the image exposure means so that the focus of the image exposure means is focused on the CCD surface; and Fixing on the supporting member via a non-conductive adhesive,
3) The method of assembling the image exposure unit according to 1) or 2), wherein the image exposure unit is an exposure optical system including a light emitting element and a lens arranged in an axial direction of the image forming body.
4) The method of assembling the image exposure means according to any one of 1) to 3), wherein the image exposure means is clamped and held on a fine movement stage.
5) The imaging surface of the CCD is moved in parallel with the axis of the support member in a state where the imaging surface is set at a position corresponding to the surface of the image forming body. Assembling method of image exposure means,
6) The method of assembling the image exposing means according to any one of 1) to 5), wherein the adjustment of the focus position of the entire image exposing means with respect to the CCD surface is performed at two places near at least both ends of the image exposing means.
7) In the adjusting step, the image exposure unit is adjusted in angle and position with respect to the CCD surface, and then moved in the vertical direction of the CCD surface. Method,
8) The CCD is a two-dimensional area type CCD,
In the adjusting step, the in-focus position is predicted by changing the focal position of the image exposing means with respect to the CCD at least at three or more positions, and measuring the half-value width or the maximum luminance, thereby adjusting the position of the image exposing means. The method of assembling the image exposure means according to any one of 1) to 7),
9) The low-curing shrinkable adhesive is an ultraviolet-curing adhesive, and in the fixing step, the image exposing means includes an adhesive member that can transmit ultraviolet light between the supporting member and the image exposing means. A method for assembling the image exposure means according to any one of 1) to 8), which is fixed by an adhesive;
Achieved by

  According to the method of assembling the image exposure means of the present invention, a plurality of image exposure means can be accurately and firmly fixed at a predetermined position with respect to the photoreceptor surface by shortening the adjustment time without incorporating an adjustment mechanism or a fixing member in the apparatus. As a result, a color image forming apparatus that has a simple structure and can be expected to reduce costs has been realized.

  Prior to the description of each embodiment, the structure and operation of a common color image forming apparatus will be described with reference to FIGS.

  FIG. 1 shows a color image forming apparatus provided with a so-called internal type image exposing means for accommodating the image exposing means inside the image forming body, but the present invention employs a type in which the image exposing means is arranged outside the image forming body. This is also applied to the color image forming apparatus described above.

  Reference numeral 10 denotes a drum-shaped image forming body, that is, a photosensitive drum, which is formed by coating an organic photosensitive layer (OPC) made of a transparent conductive layer on a basic outer periphery formed of a transparent member such as optical glass or transparent acrylic resin, and is grounded. It is driven and rotated clockwise in this state.

  Numeral 11 denotes a scorotron charger as a charging means, which performs a charging action on the above-mentioned organic photoreceptor layer of the photoreceptor drum 10 by a grid maintained at a predetermined potential and corona discharge by a discharge wire. On the other hand, a uniform potential is applied.

  Reference numeral 12 denotes an exposure optical system, which is an image exposure means, and includes light emitting elements such as LEDs, FL, EL, and PL arranged in the axial direction of the photosensitive drum 10 and a selfoc lens. Image signals of each color read by a separate image reading device are sequentially taken out of the memory and input to the exposure optical systems 12 as electric signals. The emission wavelength of the light emitting element used in this embodiment is in the range of 500 to 900 nm.

  Each of the exposure optical systems 12 is mounted on a columnar support member 20 and housed inside the base of the photosensitive drum 10. The exposure optical system 12 can be composed of a combination of an optical shutter member such as LCD, LISA, PLZT and the like, and an imaging lens such as a SELFOC lens, in addition to the above light emitting elements.

  Reference numerals 13Y, 13M, 13C, and 13K denote developing units which are developing means for storing developers of yellow (Y), magenta (M), cyan (C), and black (K), respectively. And a developing sleeve 130 that rotates in the same direction while maintaining a predetermined gap.

  Each of the developing units 13 inverts the electrostatic latent image on the photosensitive drum 10 formed by the charging by the charger 11 and the image exposure by the exposure optical system 12 in a non-contact state by applying a developing bias voltage. develop.

  Next, a process of forming a color image in the present apparatus will be described.

  The image of the original is stored in an image reading device separate from the present device, and the image read by the image sensor or the image edited by the computer is temporarily stored in the memory as image signals for each of Y, M, C and K colors. And stored.

  At the start of image recording, the photoconductor driving motor rotates to rotate the photoconductor drum 10 clockwise, and at the same time, application of a potential to the photoconductor drum 10 is started by the charging action of the charger 11 (Y).

  After the photosensitive drum 10 is applied with a potential, the exposure optical system 12 (Y) starts image exposure with an electrical signal corresponding to a first color signal, that is, an image signal of yellow (Y), and rotates the drum. As a result, an electrostatic latent image corresponding to the yellow (Y) image of the original image is formed on the photosensitive layer on the surface.

  The latent image is reversal-developed by the developing device 13 (Y) in a state where the developer on the developing sleeve is not in contact, and a yellow (Y) toner image is formed according to the rotation of the photosensitive drum 10.

  Next, the photosensitive drum 10 is further provided with a potential on the yellow (Y) toner image by the charging action of the charger 11 (M), and the second color signal of the exposure optical system 12 (M), that is, magenta (M). Image exposure is performed by an electric signal corresponding to the image signal of (3), and a magenta (M) toner image is sequentially formed on the yellow (Y) toner image by non-contact reversal development by the developing unit 13 (M). It is formed by overlapping.

  By the same process, a cyan (C) toner image corresponding to the third color signal is further formed by the charger 11 (C), the exposure optical system 12 (C), and the developing device 13 (C). (K), a black (K) toner image corresponding to the fourth color signal is sequentially superimposed by the exposure optical system 12 (K) and the developing device 13 (K), and is formed within one rotation of the photosensitive drum 10. Then, a color toner image is formed on the peripheral surface.

  The color toner image thus formed on the peripheral surface of the photosensitive drum 10 is transferred from a paper feed cassette 15 to a transfer sheet, which is a transfer material fed synchronously by the driving of a timing roller 16, in a transfer unit 14A. Transcribed.

  The transfer paper to which the toner image has been transferred is separated from the peripheral surface of the drum by the removal of the charge in the static eliminator 14B, and the toner is welded in the fixing device 17 and then on the tray at the top of the device via the paper discharge roller 18. Is discharged.

  On the other hand, the photosensitive drum 10 from which the transfer paper has been separated removes and cleans the residual toner in the cleaning device 19 to continue forming the toner image of the original image, or temporarily stops to form the toner image of the new original image. To wait.

  As shown in FIG. 2, the photosensitive drum 10 is rotatable by directly or indirectly bearing a flange shaft 10A and 10B at both ends for engaging and fixing the photosensitive drum 10 directly or indirectly to the apparatus main body. , And the gear G integrated with the flange member 10B is rotated in a predetermined direction by being driven by meshing with a drive gear on the apparatus main body side.

  The drum shaft 110 is integrally fixed by inserting a support member 20 for mounting and fixing each of the above-described exposure optical systems 12 inside the photosensitive drum 10.

  FIG. 3 shows a color image forming apparatus of another embodiment, and shows a configuration in which an exposure optical system 12 is arranged outside a photosensitive drum 10. As shown in FIG. 2 described above, the above-mentioned photosensitive drum 10 has flange members 10A and 10B at both ends for engaging and fixing it directly or indirectly to a drum shaft 110 which is fixedly mounted on the apparatus main body. The gear G integrally formed with the flange member 10B is rotated in a predetermined direction by being engaged with and driven by a driving gear on the apparatus main body side.

  FIG. 4 shows a single component of the support member 40 that holds the exposure optical system 12 of the embodiment shown in FIG. The support member 40 is a cylindrical member that encloses the photosensitive drum 10 and is concentric with the photosensitive drum. Each exposure optical system 12 is fixed to the peripheral surface of the support member 40. The slit holes opened by the support member 40 shown in FIG. 4 are provided for inserting the developing units 13 and the exposure optical systems 12.

  Each of the inventions described below relates to a method for mounting and fixing each exposure optical system 12 to the support member 20 or the support member 40 described above.

  An adjustment device 100 as shown in FIG. 5A is used to set the mounting position of each exposure optical system 12 with respect to each support member 20 in the color image forming apparatus shown in FIG.

  The adjusting device 100 includes a fine movement stage 110 that clamps and holds the exposure optical system 12, a slide table 120 that supports the CCD and moves in parallel along a linear scale, and supports the support member 20 and rotates the mounting member 20 by necessary degrees to mount the mounting surface. And a rotation angle setting means 130 having a rotary encoder for setting the position of the CCD. The imaging surface of the CCD is accurately set at a position corresponding to the photoconductor surface of the photoconductor drum 10. The support member 20 is moved parallel to the axis.

  The fine movement stage 110 adjusts the angle and position of the exposure optical system 12 with respect to the CCD surface held by fine adjustment of the horizontal and vertical angles, and further finely moves the exposure optical system 12 in the vertical direction of the CCD surface. As a result, the focus of the exposure optical system 12 is focused on the CCD surface as shown in the sectional view of the main part (FIG. 5B), and the relative positional relationship of the exposure optical system 12 with respect to the support member 20 is adjusted. Adjustment of the focus position of the entire exposure optical system 12 with respect to the CCD surface is performed at least at two places near both ends of the exposure optical system 12 by moving the slide table 120 in parallel.

On the other hand, in the case of the color image forming apparatus shown in FIG. 3 in which the exposure optical system 12 is disposed outside the photosensitive drum 10, the exposure optical system 12 is supported by using the notch of the support member 40 as shown in FIG. The fine movement stage 110 that can be held inside the member 40, the slide table 120 that can move in parallel with the axis of the photosensitive drum (the axis of the support member 40) inside the support member 40, and the support member 40 A rotation angle setting means (not shown) provided with an encoder which rotates the required angle to set the position of the mounting surface is used. In this case, as described with reference to FIG. 5, the focus of the exposure optical system 12 is focused on the CCD surface to adjust the relative positional relationship of the exposure optical system 12 with respect to the support member 40.
(Example 1)
One embodiment of the present invention will be described with reference to FIG.

  After adjusting the position of each exposure optical system 12 with respect to the CCD by the adjustment device 100 described above, the exposure optical system 12 is attached and fixed to the support member 20 via an adhesive.

  The predetermined gap between the back surface of the exposure optical system 12 and the mounting surface of the support member 20 may be an individual error including a variation in the focal length of the exposure optical system 12, an adjustment error in setting a focus position, or an error of the support member 20 itself. In consideration of manufacturing errors and the like, a minimum gap including a margin for applying the adhesive is set, and the adhesive is applied and filled in the gap.

  As the above adhesive, an adhesive having a low shrinkage ratio and a low curing shrinkage at the time of curing, such as a UV-curable modified acrylic resin-based adhesive or an epoxy resin-based adhesive, having a shrinkage ratio (volume) of 10% or less is used. You. Generally, by increasing the dimensional accuracy of the related parts, the amount of the gap required for adjustment is reduced, and the amount of the gap is set to 0.5 mm at the maximum, which is sufficient. The fluctuation amount of the exposure optical system 12 is within 0.02 mm or less at the maximum, and it can be stopped within the allowable deviation amount of the focus position in the fixed state.

Therefore, according to the present invention, the exposure optical system 12 is fixed to the predetermined position of the support member 20 with high accuracy only by the adhesive, and as a result, a fine adjustment mechanism for supporting the conventionally used exposure optical system and an exposure A screw member or the like for fixing the optical system to the support member is not required, and the cost can be reduced by simplifying the mechanism and reducing labor.
(Example 2)
Another embodiment of the present invention will be described with reference to FIG.

  According to the present invention, the focus position of the image exposure means, which has been conventionally adjusted by visual observation, can be automatically adjusted.

  The optical characteristics of the exposure optical system 12 are examined in advance, and a change in the half-width or the maximum luminance as shown in FIG. 8 corresponding to the deviation of the imaging position with respect to the normal focus position is obtained from the result. And is stored in the focus position adjustment memory. As is clear from FIG. 8, the half width is the minimum value and the maximum luminance is the maximum value at the in-focus position.

  On the other hand, the CCD supported by the slide table 120 of the adjusting device 100 is a two-dimensional area type CCD, and the CCD is adapted to correspond to the vicinity of both ends of the exposure optical system 12 set at a predetermined position in the main scanning direction. Are installed at two places on the linear scale.

  When adjusting the position of the exposure optical system 12 to the in-focus position, the half-width or the maximum luminance is measured for at least three points before and after the position including the position assumed to be the in-focus position, and the measured value is referred to as above. Is plotted (substituted) on the above program (approximate expression of a fourth order or less) to calculate the in-focus position, and automatically controls the exposure optical system 12 to move the CCD by an amount based on the calculation result. When the stop position of the exposure optical system 12 is determined, the position of the exposure optical system 12 is set using that point as the focus position. In FIG. 8, black circles indicate three measurement points, and X indicates an in-focus position obtained by arithmetic processing.

Also, by using a two-dimensional CCD, it is possible to automatically set the position of the exposure optical system 12 in the main scanning and sub-scanning directions by providing a mounting reference position on the CCD. By automatically and sequentially setting the positions in the main scanning and sub-scanning directions, the position setting of the exposure optical system 12 can be completely automated.
(Example 3)
Another embodiment of the present invention will be described with reference to FIG.

  After the position of each exposure optical system 12 with respect to the CCD is determined by the adjusting device 100 described above, the exposure optical system 12 is pasted and fixed via an adhesive after a pair of pasting members is interposed between the exposure optical system 12 and the support member 20.

  The sticking member is formed of a material that efficiently transmits ultraviolet light, and an ultraviolet-curable adhesive is used as the adhesive.

  The exposure optical system 12 shown in FIG. 9 (a) integrally has sticking members 120A provided at both ends thereof, and the adhesive applied and filled between the sticking member 12A and the mounting surface of the support member 20 is made of the above-described adhesive. It is cured and fixed by the irradiation of the ultraviolet light passing through the attaching member 120A.

  The exposure optical system 12 shown in FIG. 9B is attached to the mounting surface of the support member 20 via an L-shaped attachment member 120B, and the attachment member 120B, the exposure optical system 12, and the attachment member 120B are attached. The ultraviolet curable adhesive applied and filled between the support member 20 and the mounting surface of the support member 20 is cured and fixed by the irradiation of ultraviolet rays which are dispersed and transmitted through the application member 120B.

  Further, the exposure optical system 12 shown in FIG. 9C is attached to a mounting surface of the support member 20 via a wedge-shaped attaching member 120C for adjustment, and an attaching surface of the attaching member 120C and the supporting member 20; The adhesive applied and filled between the attaching member 120C and the exposure optical system 12 is hardened and fixed by the irradiation of the ultraviolet rays transmitted through the attaching member 120C and reflected on the inner surface.

  Therefore, the bonding work of each exposure optical system to the support member shown in FIGS. 9A to 9C is extremely easily and efficiently performed in a bright room, and is immediately adjusted by irradiating ultraviolet rays when the adjustment is performed. The exposure optical system 12 can be accurately fixed to the position.

FIG. 2 is a cross-sectional configuration diagram of an internal exposure type color image forming apparatus. FIG. 3 is a cross-sectional view illustrating a support structure of an image exposure unit in the case of internal exposure. FIG. 1 is a cross-sectional configuration diagram of a color image forming apparatus of an external exposure type. FIG. 3 is a perspective view of a support member of an image exposure unit used for external exposure. The perspective view and principal part sectional drawing which show the structure of an adjustment apparatus. Explanatory drawing which shows the attachment type to the support member used for external exposure. FIG. 4 is an explanatory view showing a method for directly fixing an image exposure unit using an adhesive. 4 is a graph of an approximate expression used for predicting a focus position of an image exposure unit. FIG. 4 is an explanatory view showing a method of indirectly fixing an image exposure unit via an attaching member.

Explanation of reference numerals

REFERENCE SIGNS LIST 10 photoconductor drum 11 charger 12 exposure optical system 13 developing device 14A transfer device 14B static eliminator 15 paper feed cassette 16 timing roller 17 fixing device 19 cleaning device 20, 40 support member 100 adjusting device 110 fine movement stage 120 slide table 130 rotation Angle setting means 120A, 120B, 120C Sticking member

Claims (9)

A plurality of charging means, image exposing means and developing means are provided around the image forming body, and a plurality of toner images are superimposed and formed on the image forming body during one rotation of the image forming body. A method of assembling an image exposure unit used in a color image forming apparatus that performs batch transfer,
Using an adjustment device that holds the image exposure unit in a position-adjustable manner, and that supports a support member to which the image exposure unit is attached, and a CCD having an imaging surface set at a position corresponding to the image forming body surface,
Moving the image exposure means in the vertical direction of the CCD surface to adjust the position of the image exposure means so that the focus of the image exposure means is focused on the CCD surface; and Fixing the image exposure means on the support member via an adhesive. A plurality of charging means, image exposing means and developing means are provided around the image forming body, and a plurality of toner images are superimposed and formed on the image forming body during one rotation of the image forming body. A method of assembling an image exposure unit used in a color image forming apparatus that performs batch transfer,
Arranging a CCD having an imaging surface set at a position corresponding to the image forming body surface on a support member to which the image exposure unit is attached;
Moving the image exposure means in the vertical direction of the CCD surface to adjust the position of the image exposure means so that the focus of the image exposure means is focused on the CCD surface; and Fixing the image exposure means on the support member via an adhesive. 3. The method according to claim 1, wherein the image exposure unit is an exposure optical system including a light emitting element and a lens arranged in an axial direction of the image forming body. 4. The method according to claim 1, wherein the image exposure unit is clamped and held on a fine movement stage. 5. The imaging surface of the CCD is moved in parallel with the axis of the support member in a state where an imaging surface is set at a position corresponding to the surface of the image forming body. 6. The method of assembling the image exposure means according to claim 1. The image according to any one of claims 1 to 5, wherein adjustment of a focus position of the entire image exposing unit with respect to the CCD surface is performed at least at two positions near both ends of the image exposing unit. How to assemble the exposure means. 7. The method according to claim 1, wherein in the adjusting step, the image exposure unit is moved in a direction perpendicular to the CCD surface after adjusting an angle and a position with respect to the CCD surface. A method for assembling the image exposure means according to the above. The CCD is a two-dimensional area type CCD,
In the adjusting step, the in-focus position is predicted by changing the focal position of the image exposing means with respect to the CCD at least at three or more positions, and measuring the half-value width or the maximum luminance, thereby adjusting the position of the image exposing means. 8. The method according to claim 1, wherein the image exposure is performed. The low-curing shrinkable adhesive is an ultraviolet-curable adhesive, and in the fixing step, the image exposing means includes an adhesive member that can transmit ultraviolet light between the supporting member and the adhesive. 9. The method according to claim 1, wherein the image exposure unit is fixed.

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