JP2006001166A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus having a scanning optical device capable of greatly inclining a scanning line in a magnitude equal to that of a conventional scanning optical device. <P>SOLUTION: The scanning optical device is attached to a body of the image forming apparatus by two portions of fitting of shafts with holes. Ones of the shafts and the holes are provided in the scanning optical device and the others are to the body. The inclination of the scanning optical device is adjusted by adjusting one of the heights of the shaft and the hole. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an image forming apparatus including a scanning optical device used for image formation such as a copying machine, a printer, and a FAX.

  In the case of using a bending mirror, the inclination of the scanning line of the conventional scanning optical device is corrected by correcting the mirror. In the case where the light beam is straight from the polygon to the image plane (straight path), an image forming apparatus provided with a technique in which the scanning optical device on the support is tilted or a scanning optical device that is performed by swinging the CY2 lens in the scanning optical device There is a technology.

In addition, the exposure apparatus is supported at three points, and the support at at least one point is a support structure that can rotate in all directions by a spherical bearing, so that the tilt of the laser beam in the main scanning direction and the variation in magnification in the main scanning direction can be adjusted. An image forming apparatus including a scanning optical device is known (see Patent Document 1).
JP 2002-90678 A

  However, in the image forming apparatus provided with the scanning optical device, the former has a problem that the whole apparatus becomes large (cost increase), and the latter has a problem that it cannot be tilted greatly due to the effective area of the lens.

  An object of the present invention is to provide an image forming apparatus including a scanning optical device that solves the above-described problems and is capable of tilting a scanning line with a size equivalent to that of a normal scanning optical device.

  The object is to provide an image carrier, a charging means for charging the surface of the image carrier, a scanning optical device for forming an electrostatic latent image by irradiating the image carrier with light, and the image carrier. And a developing means for developing a toner image by developing the electrostatic latent image formed on the scanning optical device. The scanning optical device is attached to the apparatus main body by fitting two shafts and holes. One of the shaft and the hole is provided in the scanning optical device and the other is provided in the apparatus main body, and the inclination of the scanning optical device is adjusted by adjusting the height of one of the shaft and the hole. This is achieved by the featured image forming apparatus.

  The present invention is intended to provide an image forming apparatus provided with a scanning optical device having a configuration equivalent to that of a normal scanning optical device and capable of tilting a scanning line greatly.

  According to the present invention, it is possible to provide an image forming apparatus including a scanning optical device that can tilt the scanning line with a size equivalent to that of a normal scanning optical device.

  Embodiments of the present invention will be described below. The description in this column does not limit the technical scope of the claims or the meaning of terms. In addition, the following assertive description in the embodiment of the present invention shows the best mode, and does not limit the meaning or technical scope of the terms of the present invention.

  (1) An image forming apparatus including a scanning optical apparatus according to the present invention will be described below with reference to FIG. FIG. 1 is a schematic sectional view of an image forming apparatus provided with a scanning optical device according to the present invention.

  In FIG. 1, the image forming apparatus GS includes an image forming apparatus main body GH and an image reading apparatus YS.

  The image forming apparatus main body GH is called a tandem type color image forming apparatus, and includes a plurality of sets of image forming units 10Y, 10M, 10C, and 10K, a belt-like intermediate transfer member 6, a sheet feeding and conveying unit, and a separation assist. Means and a fixing device 17.

  An image reading device YS including an automatic document feeder 201 and a document image scanning exposure device 202 is installed on the upper part of the image forming apparatus main body GH. The document d placed on the document table of the automatic document feeder 201 is transported by a transport unit, and an image on one or both sides of the document is scanned and exposed by the optical system of the document image scanning exposure device 202, and the line image sensor CCD is scanned. Is read.

  The analog signal photoelectrically converted by the line image sensor CCD is subjected to analog processing, A / D conversion, shading correction, image compression processing, and the like in an image processing unit, and then an image writing unit (scanning optical device) 800Y, 800M. , 800C, 800K.

  The image forming unit 10Y for forming a yellow (Y) image includes a scanning optical unit 800Y as a scanning optical device for the charging means 2Y and Y arranged around the photosensitive drum 1Y as an image carrier, and a developing device 4Y. And a cleaning means 8Y. An image forming unit 10M that forms a magenta (M) color image includes a photosensitive drum 1M as an image carrier, a charging unit 2M, a scanning optical unit 800M as a scanning optical device of M, a developing unit 4M, and a cleaning unit 8M. Have. An image forming unit 10C for forming a cyan (C) color image includes a photosensitive drum 1C as an image carrier, a charging unit 2C, a scanning optical unit 800C as a scanning optical device for C, a developing unit 4C, and a cleaning unit 8C. Have. An image forming unit 10K that forms a black (K) image includes a photosensitive drum 1K as an image carrier, a charging unit 2K, a scanning optical unit 800K as a scanning optical device for K, a developing unit 4K, and a cleaning unit 8K. Have. The charging unit 2Y and the exposure unit 3Y, the charging unit 2M and the scanning optical unit 800M, the charging unit 2C and the scanning optical unit 800C, and the charging unit 2K and the scanning optical unit 800K constitute a latent image forming unit.

  4Y, 4M, 4C, and 4K are developing devices that include a two-component developer composed of a toner having a small particle diameter and a carrier of yellow (Y), magenta (M), cyan (C), and black (K). .

  The intermediate transfer body 6 is wound around a plurality of rollers and is rotatably supported.

  The images of the respective colors formed by the image forming units 10Y, 10M, 10C, and 10K are sequentially transferred (primary transfer) onto the rotating intermediate transfer body 6 by the transfer means 7Y, 7M, 7C, and 7K. A synthesized color image is formed on the belt 6. The recording paper P as a transfer material accommodated in the paper feed cassette 20 is fed by the paper feed means 21 and is conveyed to the transfer means 7A via the paper feed rollers 22A, 22B, 22C, the registration rollers 23, etc. A color image is transferred onto the recording paper P (secondary transfer). The recording paper P on which the color image is transferred is conveyed to the fixing device 17. The recording paper P on which the color toner image (or toner image) has been fixed by applying heat and pressure in the fixing device 17 is sandwiched between the paper discharge rollers 24 and discharged onto a paper discharge tray 25 outside the apparatus. .

  On the other hand, the toner remaining on the intermediate transfer body 6 after the color image is transferred to the recording paper P by the transfer means 7A is removed by the cleaning means 8A.

  The apparatus body is provided with a body panel HPa to which the scanning optical devices 800Y, 800M, 800C and 800K are attached.

  In the description of the image forming apparatus, the color image formation is described. However, the present invention includes a case where a monochrome image is formed.

  (2) An embodiment of a beam-type scanning optical apparatus according to the present invention will be described. FIG. 2 is a perspective view showing a scanning optical device using a light deflecting device for a polygon mirror according to the present invention.

  In FIG. 2, a scanning optical unit 800 used in combination with a scanning optical apparatus includes a semiconductor laser 80 as a light source, a collimator lens 81 as a first optical system of a beam shaping optical system, and a first cylindrical lens 82. , 83 are polygon mirrors as a second optical system, 84A and 84B are fθ lenses as polarization means, 85 is a second cylindrical lens, 86 is a mirror, 87 is a cover glass, and 88 is a photosensitive drum. . Reference numeral 89 denotes an index mirror for synchronization detection, 89S denotes an index sensor for synchronization detection, and 83M denotes a rotation driving unit of the polygon mirror 83 of the optical deflector. The above members are attached to the casing KTa (see FIG. 3) of the scanning optical unit 800.

  The beam emitted from the semiconductor laser 80 becomes parallel light by the collimator lens 81, and enters the mirror surface of the polygon mirror 83 that rotates at a constant speed through the first cylindrical lens 82. The reflected light passes through the fθ lenses 84A and 84B and the second cylindrical lens 85, and (main) scanning is performed with a predetermined spot diameter on the peripheral surface of the photosensitive drum 88 via the mirror 86 and the cover glass 87. The main scanning direction is finely adjusted by an adjustment mechanism (not shown), and synchronization detection for each line is performed by making the beam before the scan start enter the index sensor 89S via the index mirror 89.

  (3) A method of correcting the tilt of the scanning optical apparatus according to the present invention will be described with reference to FIGS. FIG. 3 is a diagram showing the attachment of the main body of the image forming apparatus described in FIG. 1 by fitting two main body side holes and two scanning optical apparatus side shafts. FIG. FIG. 5 is a diagram showing a fitting shaft on the side of the scanning optical unit provided in the optical device, FIG. 5 is a diagram showing a drive unit of the rotating shaft, and FIG. 6 is a perspective view of the rotating shaft. 7 is a diagram of an axis when the main body panel side is an axis and the scanning optical unit side is a hole.

  According to FIG. 3 or FIG. 4, the hole Ha shown in FIG. 3 fitted to the fixed axis KJa shown in FIG. 4 and the fixed axis KJa for adjusting the height of the scanning optical device 800 shown in FIG. 4 are fitted. A long hole Hb is provided. 4 is a diagram showing the drive unit KDU.

  According to FIG. 5 or FIG. 6, the drive unit KDU includes a gear (flat teeth) 1Ga rotated by the motor M, a gear (flat teeth) 2Gb that meshes with the gear 1Ga and rotates, and the gear 2Gb. The rotating shaft Jta is rotated by the rotated gear (worm) 4Gd and the gear (lotus tooth) 3Gc meshed with the gear 4Gd. As shown in FIG. 6, the rotation axis Jta, which is a fitting position with the main body of the scanning optical unit 800, is in an eccentric state with respect to the gear portion.

  In the scanning optical unit 800, the tilt correction of the scanning optical unit 800 as the scanning optical device is performed by adjusting the height of the rotation axis Jta. The height of the rotation shaft Jta is adjusted by rotation (see FIG. 6) of the rotation shaft Jta (eccentric portion) in an eccentric state using gear drive of the drive unit KDU.

  According to FIG. 7, when the main body side is an axis and the scanning optical unit side is a hole, the correction of the inclination of the scanning optical unit 800 as a scanning optical device is performed by a drive unit KDU (see FIG. 3) attached to the main body panel HPa (see FIG. 3). 5), one of the two fixed shafts (not shown) provided in the scanning optical device 800 (see FIG. 3) is fitted into the long hole Hc in an eccentric state. It is. The center of the long hole Hc is shifted from the center of one fixed shaft (not shown). Adjustment of the height of the hole is performed by rotation of the long hole Hb2 (eccentric part) of the shaft Jt in an eccentric state as a receiving hole using the gear drive of the drive unit KDU provided in the main body panel HPa.

  Note that, even when there are a plurality of scanning optical devices by the height adjustment, the scanning lines of the plurality of scanning optical units 800 are adjusted in parallel.

  As described above, by adopting the configuration of the present invention, it is possible to obtain an image forming apparatus including a scanning optical device capable of greatly tilting a scanning line with the same size as a normal scanning optical device.

1 is a schematic cross-sectional configuration diagram of an image forming apparatus including a scanning optical device according to the present invention. 1 is a perspective view showing a scanning optical device using an optical deflecting device of a polygon mirror according to the present invention. It is a figure which shows what the main body attachment of the image forming apparatus is made by fitting two main body side holes and two scanning optical device side shafts. It is a figure which shows the fitting shaft by the side of the scanning optical unit of two places provided in a scanning optical unit. It is a figure which shows the drive unit of a rotating shaft. It is a perspective view of a rotating shaft. It is a figure of the axis | shaft in case a main body panel side is an axis | shaft and the scanning optical unit side is a hole.

Explanation of symbols

1Y, 1M, 1C, 1K Photosensitive drum 2Y, 2M, 2C, 2K Charging means 3Y, 3M, 3C, 3K Exposure means 4Y, 4M, 4C, 4K Developing device 17 Fixing device 80 Semiconductor laser 81 Collimator lens 83 Polygon mirror 84A , 84B fθ lens 800 scanning optical unit 800Y, 800M, 800C, 800K scanning optical device Ga gear (flat tooth) 1
Gb gear (flat teeth) 2
Gc Gear (Lotus tooth) 3
Gd Gear (Worm) 4
Ha hole Hb Long hole Hc Long hole HPa Main body panel Jt axis Jta Rotating axis KDU Drive unit KJa Fixed axis KTa Housing M Motor P Recording paper

Claims (5)

An image carrier, a charging means for charging the surface of the image carrier, a scanning optical device for forming an electrostatic latent image by irradiating the image carrier with light, and formed on the image carrier. An image forming apparatus comprising: a developing unit that develops an electrostatic latent image to form a toner image;
The scanning optical device is attached to the device main body by fitting two shafts and holes,
One of the shaft and the hole is provided in the scanning optical device, the other is provided in the device main body,
An image forming apparatus comprising: adjusting an inclination of the scanning optical device by adjusting a height of one of the shaft and the hole. The image forming apparatus according to claim 1, wherein the adjustment of the shaft height is performed by rotation of an eccentric portion provided in one of the shaft and the hole. The image forming apparatus according to claim 1, wherein one of the two fittings is fixed. The image forming apparatus according to claim 1, wherein the height adjustment is performed by rotating a shaft using a gear drive. The image recording apparatus according to claim 1, further comprising a plurality of scanning optical devices.

Images