JP2002311364A - Scanning optical device and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high-quality scanning optical device and a high-quality image forming device capable of preventing the deviation of an irradiating position. SOLUTION: This optical device is equipped with positioning plates (L) 35 and (R) 36 fixed and supported by laser scanner stays (L) 25 and (R) 26. This device positions and holds an optical box 24 on the laser scanner stays (L) 25 and (R) 26 after the laser scanner stays (L) 25 and (R) 26 are positioned by screw and fixed on front and back side plates 40 and 41.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a copying machine having a function of forming an image on a recording medium such as a sheet.
The present invention relates to an image forming apparatus such as a printer or a facsimile apparatus, and more particularly, to a scanning optical apparatus provided in these apparatuses.

[0002]

2. Description of the Related Art FIG. 6 is a view showing the configuration of a conventional image forming apparatus. In FIG. 6, reference numeral 1 denotes an image forming section as image forming means for forming an image by an electrophotographic process. Reference numeral 1 denotes a photosensitive drum 10 as an image carrier, a laser scanner unit 9a as a scanning optical device for exposing the surface of the photosensitive drum 10 to form an electrostatic latent image on the photosensitive drum 10, and on the photosensitive drum 10. And a developing unit 11 for developing the latent image formed on the image forming apparatus.

Reference numeral 2 denotes a cassette for accommodating a recording material 3 as a sheet, and reference numeral 6 denotes a paper feeding / conveying unit for conveying the recording material 3 to the image forming unit 1. And a registration roller 8 for correcting the skew of the recording material 3 and the like.

[0004] Reference numeral 14 denotes a paper discharge transport section for transporting the recording material 3 on which an image has been formed by the image forming section 1 to a paper discharge tray 17 serving as a paper discharge section. And a sheet discharge roller 16 and the like.

In the image forming apparatus having such a configuration, when forming an image, the recording material 3 stored in the cassette 2 is first picked up by a pickup roller 4 and then separated by a separation unit 5 into one sheet. The sheet is separated and sent to the sheet feeder 6. Thereafter, the recording material 3 is reversed by the reversing guide unit 7, and the skew of the recording material 3 is corrected by the registration roller 8, and then the recording material 3 is guided to the image forming unit 1.

When the recording material 3 passes through the top sensor 18 provided in front of the image forming unit 1, the laser scanner of the laser scanner unit 9a of the image forming unit 1 starts operating synchronously, and operates on the photosensitive drum 10. Is irradiated with a laser to form an electrostatic latent image. Thereafter, the electrostatic latent image is visualized by the developing unit 11 and then transferred to the recording material 3 by the transfer unit 12.

After the visible image is transferred as described above, the recording material 3 is guided to a fixing unit 13 by a guide 19, and the visible image is fixed by heating and pressing in the fixing unit 13, thereby forming an image. Ends. After that, the recording material 3 is sent to the paper discharge transport section 14, and is stacked on the paper discharge tray 17 by the paper discharge roller 16 via the reversing guide 15.

Next, the laser scanner unit 9a as an exposure system will be described.

FIGS. 7 and 8 show a laser scanner unit 9.
It is a detailed view of a.

In FIG. 1, reference numeral 20 denotes a laser as a light source unit; 21 denotes a deflection scanning means; a polygon motor for driving a polygon mirror for deflecting and scanning the laser beam from the laser 20 onto the photosensitive drum 10; An optical lens group as an optical member for uniformly scanning the photosensitive drum 10 is shown. A folding mirror 23 is a folding member that reflects laser light onto the photosensitive drum 10.

These laser 20 and polygon motor 2
1. The optical lens group 22 and the folding mirror 23 are integrally fixed to a mold frame called an optical box 24 as a housing.

The optical box 24 is made of a resin member, and is made of PC-ABS containing 35% of GF (glass fiber), and has high rigidity, light weight, and low cost.

Further, the optical box 24 is supported by a laser scanner stay (L) 25 and a laser scanner stay (R) 26, which are iron casings having a thickness of 3.2 mm. These two laser scanner stays 25 and 26 are connected to the front and rear side plates 40 and 41 and hold the position of the laser scanner unit 9a.

The two laser scanner stays 25,
Reference numeral 26 denotes a jig in which the mounting surface of the laser scanner unit 9a is suppressed to a flatness of 0.1 or less when incorporated into the main body, so that the optical component is not deformed when tightened with the screw 32.

FIG. 9 is a view showing a state where the laser scanner 9a is removed.

The four mounting surfaces 37 of the laser scanner stay (L) 25 and the laser scanner stay (R) 26 on which the laser scanner unit 9a is mounted are fixed with jigs having flatness, and positioning holes are formed with the same jigs. The reference numeral 31 is fixed to a nominal position with respect to the axial hole 42 of the pseudo photosensitive drum 10 provided on the front and rear side plates 40 and 41, and in this state, the front and rear side plates 40 and 41 and the laser scanner stay (L) 25 are screwed. , (R) 26 are fastened.

Thereafter, the jig is removed and the laser scanner unit 9a is mounted.

The laser scanner unit 9a is positioned by positioning pins (L) 27 and positioning pins (R) 28.
Done by The positioning pins 27 and 28 are separate parts from the optical box 24, and are located in another place, that is, on a jig.
By moving the position of the optical box 24 in the front, rear, left and right directions indicated by 29 in FIG. 7 in a state where the positioning pins 27 and 28 are positioned, the optical box 24 is previously provided on the jig.
The laser light is adjusted to be incident on the light receiving sensor at the correct irradiation position, and the positioning pins 27 and 28 and the optical box 24 are fixed by three screws 30.

In this conventional example, the irradiation position is not adjusted on the apparatus main body, the laser scanner unit 9a is adjusted on the jig in advance, and the two positioning positions opened by the laser scanner stays 25 and 26 on the apparatus main body. Hole 3
Just plug in one. Naturally, the positioning holes 31 of the laser scanner stays 25 and 26 are accurately processed at the component level.

The reason for adopting such a method is that if the laser scanner unit 9a is damaged in the market, if the laser scanner unit 9a is replaced,
This is because the irradiation position does not change even after replacement since the adjustment is made in advance on the jig, and compatibility is guaranteed.

The laser scanner unit 9a is fixed with four screws 32, and four outer peripheral portions are fixed to the laser scanner stays 25 and 26. further,
As shown in FIG. 10, dustproof lids 33 and 34 are attached, but this part is naturally attached on a jig in advance. FIG. 7 is described with the lid removed for easy understanding.

[0022]

However, in the case of the laser scanner unit 9a having the configuration as in the prior art described above, there is a problem that the accuracy of the positioning hole 31 varies.

As described above, the loading surface 3 on which the laser scanner units 9a of the laser scanner stay (L) 25 and the laser scanner stay (R) 26 are mounted.
7 are fixed with a jig having a plane accuracy, and the positioning jig 31 is fixed at the nominal position with respect to the axis hole 42 of the pseudo drum provided on the front and rear side plates by the same jig. Then, the front and rear side plates 40 and 41 and the laser scanner stays (L) 25 and (R) 26 are fastened with screws.

Thereafter, the jig is removed, and the laser scanner unit 9a is mounted. When the jig is removed, the force applied to the front and rear side plates 40, 41 and the laser scanner stays (L) 25, (R) 26 generated at the time of screw fastening. When the residual stress releases the jig, the accuracy held by the jig is destroyed by the release of the distortion and residual stress, and even if the jig is used for the purpose, it finally becomes meaningless.

Moreover, this deviation is good or bad depending on the order of fastening the screws, the force of the operator, and the like, so that the deviation is large and it is difficult to uniformly correct the deviation by another means.
This step is, of course, the first step of the mechanical assembly, and the electrical unit, the reader, the laser scanner unit 9a, the image forming unit 1, the sheet feeding and conveying unit 6, the sheet discharging and conveying unit 14 and the like are attached without being shifted. If it is not at the final stage of image confirmation, the deviation is not known, and if a deviation occurs at the final stage,
The machine had to be disassembled again and the jigs reassembled, which wasted a great deal of time.

Also, after the jig is removed, a jig for checking may be further formed and only the OK one may be transferred to the subsequent work. However, new equipment investment, jig cost and inspection man-hours are required, which naturally increases the cost. turn into.

As another countermeasure, there is a method of stopping the adjustment on the jig and fixing the positions of the positioning pins 27 and 28 with the messing screw 30 just before the final image check to adjust the irradiation position. However, in this case, the number of adjustment steps also increases, and the cost increases.

Further, when the laser scanner is broken, the laser scanner unit 9a must be readjusted in the market, which imposes a heavy burden on the user and the service person.

Further, in the market, when it is difficult to cope with the situation, a heavy load is imposed such as returning to a factory for readjustment.

The present invention has been made to solve the above-mentioned problems of the prior art, and an object of the present invention is to provide a high quality scanning optical apparatus and an image forming apparatus capable of preventing irradiation position deviation. To provide.

[0031]

According to the present invention, there is provided a light source unit, deflection scanning means for deflecting and scanning a light beam from the light source unit, and deflection scanning by the deflection scanning means. A scanning optical device comprising: an optical member for condensing the light flux on a predetermined surface; and a housing to which the light source unit, the deflection scanning unit, and the optical member are attached. And a positioning and holding member for positioning and holding the housing to the frame.

The positioning and holding member is positioned and held together with the frame by a jig, held by holding means provided on the jig, and then the assembled frame is released from the holding state by the holding means. After that, it is also preferable to be fixedly supported by the frame.

It is also preferable that the apparatus further comprises a position adjusting means for moving the positioning holding member with respect to the frame.

The position adjusting means includes concave portions provided on the positioning and holding member and the frame, respectively. The jig of the jig fitted into the concave portions provided on the positioning and holding member and the frame, respectively. It is also preferable that the positioning and holding member be moved with respect to the frame by movement.

The first positioning / holding portion provided on the positioning / holding member for positioning and holding the housing is provided vertically with respect to the position on the predetermined surface where the light beam deflected and scanned by the deflection scanning means is condensed. It is also preferable to be located near the line.

The positioning and holding member is configured to swingably hold the housing by a first positioning and holding portion of at least two positioning and holding portions, and the first positioning and holding portion is controlled by the deflection scanning means. The deflected and scanned light beam is positioned so as to be located in the vicinity of the vertical line with respect to the position on the predetermined surface where the light beam is condensed. It is also preferable to be swung with respect to this.

The casing has two positioning portions, and the positioning and holding members are provided for the two positioning portions of the housing, respectively. The first positioning / holding unit holds the housing so as to be swingable, and the first positioning / holding unit positions the light beam deflected and scanned by the deflection scanning unit on the predetermined surface. The second positioning and holding member is positioned so as to be located in the vicinity of a vertical line, and the second positioning and holding member is swung by the position adjusting means with the housing with respect to the frame with the first positioning and holding portion as a swing center. It is also suitable.

It is also preferable that the positioning and holding member is positioned so that the first positioning and holding portion is located near a vertical line substantially at the center of the light beam condensed on the predetermined surface in the scanning direction. It is.

The image forming apparatus has the scanning optical device described above and an image carrier as the predetermined surface, and develops the electrostatic latent image formed on the image carrier by the scanning optical device. And an image forming means for transferring the toner image obtained as described above to a recording material.

[0040]

Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, the dimensions of the components described in this embodiment,
The material, shape, and their relative arrangement should be appropriately changed depending on the configuration of the apparatus to which the invention is applied and various conditions, and are not intended to limit the scope of the invention to the following embodiments.

FIG. 1 is a view showing a schematic configuration of a copying machine which is an example of an image forming apparatus according to an embodiment of the present invention. FIGS. 2 and 3 show details of a laser scanner unit according to this embodiment. FIG. The same components as those described in the section of the related art are denoted by the same reference numerals, and description thereof will be omitted.

In FIG. 1, reference numeral 1 denotes an image forming unit as image forming means for forming an image by an electrophotographic process. The image forming unit 1 has a predetermined surface, a photosensitive drum 10 as an image carrier, and a photosensitive drum 10. A laser scanner unit 9 as a scanning optical device for exposing the surface of the photosensitive drum 10 to form an electrostatic latent image on the photosensitive drum 10, a developing unit 11 for developing the latent image formed on the photosensitive drum 10, and the like. It has.

Reference numeral 2 denotes a cassette for storing the recording material 3 as a sheet, and reference numeral 6 denotes a paper feeding and conveying unit for conveying the recording material 3 to the image forming unit 1. And a registration roller 8 for correcting the skew of the recording material 3 and the like.

Numeral 14 denotes a paper discharge transport section for transporting the recording material 3 on which an image has been formed by the image forming section 1 to a paper discharge tray 17 serving as a paper discharge section. And a sheet discharge roller 16 and the like.

In the image forming apparatus having such a configuration, at the time of image formation, the recording material 3 stored in the cassette 2 is first picked up by the pickup roller 4 and then separated by the separation unit 5 into one sheet. The sheet is separated and sent to the sheet feeder 6. Thereafter, the recording material 3 is reversed by the reversing guide unit 7, and the skew of the recording material 3 is corrected by the registration roller 8, and thereafter, is guided to the image forming unit 1.

When the recording material 3 passes through the top sensor 18 provided in front of the image forming unit 1, the laser scanner of the laser scanner unit 9 of the image forming unit 1 starts operating in synchronization with the photosensitive drum 10 Is irradiated with a laser to form an electrostatic latent image. Thereafter, the electrostatic latent image is visualized by the developing unit 11 and then transferred to the recording material 3 by the transfer unit 12.

After the visible image is transferred in this manner, the recording material 3 is guided to the fixing unit 13 by the guide 19, and the visible image is fixed by heating and pressing in the fixing unit 13 to form the image. Ends. After that, the recording material 3 is sent to the paper discharge transport section 14, and is stacked on the paper discharge tray 17 by the paper discharge roller 16 via the reversing guide 15.

Next, the laser scanner unit 9 as an exposure system will be described.

As a characteristic configuration of this embodiment, FIG.
As shown in the figure, a positioning holding member, which is a small sheet metal, is provided with a fitting hole for fitting positioning pins 27 and 28 as positioning portions of the laser scanner unit 9 as a housing, and positions and holds the laser scanner unit 9. Positioning plate (L) 35 and positioning plate (R) 36
Is provided. The laser scanner unit 9 is positioned so that the positioning pins 27 and 28 are fitted to the positioning plate (L) 35 and the positioning plate (R) 36, and the laser scanner stay (L) 25 as a frame is fixed by screws 43 and 44. , (R) 26.

In other words, the laser scanner stays (L) 25 and (R) 26 are fixed via the positioning plate (L) 35 and the positioning plate (R) 36.

Next, a method of assembling the positioning plate (L) 35 and the positioning plate (R) 36 will be described.

FIG. 4 shows a state before the laser scanner unit 9 is mounted. Reference numeral 45 denotes a jig for assembling the positioning plate (L) 35 and the positioning plate (R) 36. This jig is provided at a position corresponding to the photosensitive drum indicated by 42 so as to be a reference of the photosensitive drum, and the front and rear side plates 4 serving as a frame for actually positioning the photosensitive drum 10 are provided.
0, 41 are inserted into holes 42 provided. Based on this, first, the laser scanner stay (L) 2
The loading surface 37 of the laser scanner unit 9 of 5, (R) 26 is fixed by an electromagnet as a strong holding means, and four points of flatness are obtained. As a standard, a flatness of 0.1 or less is guaranteed with the jig removed.

At the same time, positioning pins 46,
47 is a positioning plate (L) 35 and a positioning plate (R) 36
The position is determined by fitting into the positioning holes 48 and 49 formed in the holes. Here, the position of the positioning plate (L) 35 is determined by two sets of pins 46 and positioning holes 48, while the positioning plate (R) 36 is formed by two sets of embosses and holes 50 in only the vertical direction 51 in the figure. Since it is configured to have a degree of freedom, it is positioned by one positioning pin 47 and a long hole 49.

The reason why such a configuration is adopted is that when the position of the positioning plate (R) 36 is adjusted by the eccentric shaft, which will be described later, the positioning plate (R) 36 can be smoothly moved only in a necessary direction. Further, the other holes 54 allow the screw points of the fixing screws 30 of the positioning pins 27 and 28 attached to the laser scanner unit 9 to escape.

Four positions 55 are used for positioning plate (L) 35 and positioning plate (R) 36 with laser scanner stay (L) 2.
5, (R) 26 is a fixing tap for a screw for fixing to the (R) 26, but at this point, fixing by a screw is not yet performed.

In the next stage, first, the laser scanner stays (L) 25 and (R) 26 are attached to the front and rear side plates 40 and 41.
To the front and rear side plates 40,
The other frame stays (not shown) fixed by 41 are simultaneously screwed and fixed.

As described above, the laser scanner unit 9
When the flatness of the loading surface 37 is finished, the electromagnet that has been sucking the loading surface 37 is turned off. However, the electromagnet
At the moment of the FF, the laser scanner stays (L) 25 and (R) 26 are distorted and displaced due to the stress generated by screwing the front and rear side plates 40 and 41 as described above.

However, at this stage, the positioning plate (L) 35 and the positioning plate (R) 36 for positioning the laser scanner unit 9 are not screwed and are still positioned by the jig. Even if the stays (L) 25 and (R) 26 move, the positioning plates (L) 35 and (R) 36 maintain their positions without being affected by stress.

In the next stage, the positioning plate (L) 35,
Positioning plate (R) 36 with laser scanner stay (L)
25, four taps 55 for fixing to (R) 26
The screw is fastened and fixed.

Finally, the jig 45 is removed. Even if the jig 45 is removed at this stage, no displacement occurs because the stress has already been released at the stage when the electromagnet is turned off.

By taking such a setup, the laser scanner stay (L) 25,
The effect of deformation and distortion generated by screwing the (R) 26 to the front and rear side plates 40 and 41 is affected by the positioning plate (L) 3.
5. Since the positioning plate (R) 36 is not yet screwed, it is not affected, and the positioning holes 48 and 49 do not shift even if the jig is removed thereafter.

By taking such a configuration / procedure,
Variations in the positioning holes 48 and 49 are eliminated, and the irradiation position shift, the increase in the number of working steps as described above, and the compatibility of the laser scanner unit 9 in the market are ensured.

In the present embodiment, the loading surface 37 is fixed by an electromagnet as holding means, but may be fixed by screws. That is, when the laser scanner stays (L) 25 and (R) 26 are fixed to the front and rear side plates 40 and 41, the flatness of the loading surface 37 of the laser scanner unit 9 can be reliably determined, and the flatness determination is completed. After that, it is sufficient if the fixed state of the loading surface 37 can be released.

Further, in this embodiment, as shown in FIGS. 2 and 4, holes 52 and 53 as concave portions are provided in the positioning plate (R) 36 and the laser scanner stay (R) 26.

In general, even if the positioning holes 48 and 49 of the frame are adjusted once with a jig, if the floor on which the machine is installed is extremely uneven, the frame may be twisted slightly. As a result, the positioning holes 48 and 49 may be displaced.

Also, in the process, an excessive force is applied to the frame due to an error of the assembler such as a collision, a drop or a stepping on the frame, and the frame is deformed, and similarly, the positions of the positioning holes 48 and 49 may be shifted.

In this case, reassembling from the beginning is a great waste of time and cost. Alternatively, if it is absolutely necessary to install the floor on an uneven market in the installed market, it is necessary to take some measures.

To cope with such a situation, in the present embodiment, the skew of the reading position of the laser scanner unit 9 is adjusted by the position adjusting means.

Here, the reason why the adjustment is only skew is that, in general, when the image does not skew and shifts in the paper feed direction, it can be readjusted simply by changing the image writing timing by software. Also, when the image is shifted in the image scanning direction,
As a matter of course, it is possible to take measures simply by changing the setting of the writing start timing by software, and such measures are easy and quick.

However, it is difficult to correct skew of an image in software unless high-grade image processing means is provided. For this reason, the adjustment is made only in skew.

In this embodiment, when the image is skewed, the eccentric shaft 5 as a jig as shown in FIG.
The adjustment is performed using 6.

Specifically, by inserting an eccentric shaft 56 having two eccentric shafts into the holes 52 and 53 and rotating the positioning plate (R) 36 in the direction of the arrow, a laser beam is applied to this plate. Since the positioning pin 28 of the scanner is stuck, the right side of the laser scanner in the figure rotates around the positioning pin 27. As a result, the skew can be adjusted.

By providing the positioning plate with the adjusting mechanism, it is possible to easily and inexpensively cope with the above-mentioned unexpected situation, and to improve the productivity in the factory, the serviceability in the market, and the reliability of the image quality. The performance is improved.

Further, the position adjusting means may be adjusted by, for example, a screw and a spring, or may be adjusted by hand. However, the method using two holes and an eccentric shaft as described above uses the eccentric shaft as a jig. By simply preparing, the cost is low as a product, and the adjustment accuracy can be performed with much higher accuracy and faster than manual adjustment. That is, it is inexpensive and excellent in workability and accuracy.

Next, as shown in FIG. 3, in this embodiment, the position of the positioning pin 27 and the position of the actual writing position 38 on the photosensitive drum 10 are on the same vertical line and at the center in the scanning direction. . By doing so, the photosensitive drum 10 rotates about the writing position center, and even if the skew adjustment is performed, the image does not shift in the paper feed direction or the scanning direction. This is to prevent the wastefulness of the other part from being adjusted. If the positioning pin 27 positioned on the positioning plate (L) 35 is located on the same vertical line with respect to the writing position 38, it is possible to suppress the deviation of the irradiation position due to an error generated at the time of assembly.

With this configuration, the adjustment workability is remarkably improved, and the productivity is improved.

Here, in this embodiment, the laser scanner stays (L) 25 and (R) 26 are divided into two pieces. There is no problem even if it is acceptable.

Further, as positioning means, a shaft / positioning plate (L) 35,
(R) 36 is provided with holes. Conversely, holes / positioning plates (L) 35 and (R) 36 are provided on the laser scanner unit 9 side.
May be used as an axis. In this case, the visibility at the time of setting is improved.

Further, two positioning plates (L) 35 and (R) 36 are used as the positioning and holding members, but either one of them can be used as long as the accuracy of one side can be guaranteed at the component level.

In the present embodiment, the positioning between the two members is performed by fitting the hole and the shaft. For example, the positioning is performed such that one side of the hole is abutted against the reference side by a spring or the like. Is also good. In this case, the cost increases, but the play position does not occur, so that the accuracy of the irradiation position is improved.

The position adjusting means is also provided with a positioning plate (R).
36 and the laser scanner stay (R) 26, and both the positioning plate (L) 35 and the laser scanner stay (L) 25.

The point is that the number, position, etc. of the parts are arbitrary according to the precision and quality specifications of the parts.

As described above, according to the present embodiment,
The positioning plates (L) 35 and (R) 36 are provided on the positioning / loading portion of the laser scanner unit 9 and the jig adjustment is performed, so that the laser scanner stay (L) 25,
(R) 26 is not affected by the deformation and distortion caused by screwing it to the front and rear side plates 40 and 41, and the positioning holes 4 are not affected.
8, 49 does not shift.

Accordingly, variations in the positioning holes 48 and 49 can be eliminated, the displacement of the irradiation position and the increase in the number of man-hours for assembling can be prevented, and the compatibility of the laser scanner unit 9 in the market can be ensured.

Furthermore, by providing the positioning plate with an adjusting mechanism, it is possible to easily and inexpensively cope with accidents such as a work error or an installation environment, thereby improving the productivity in the factory and the serviceability in the market. Image quality reliability is improved.

Further, by using the above-described method using two holes and an eccentric shaft as the position adjusting means, it is only necessary to prepare an eccentric shaft as a jig. In addition, the adjustment accuracy can be made much higher and faster than manual adjustment, and it is inexpensive, has excellent workability and accuracy, and improves the productivity in the factory and the serviceability in the market.

Further, the position of the positioning pin 27 and the position of the actual writing position 38 on the photosensitive drum 10 are set on the same vertical line and at the center in the scanning direction, so that the writing position center on the drum can be adjusted. As a result, even if the skew is adjusted by the position adjusting means, the image is not shifted in the paper feeding direction or the scanning direction, so that the adjustment workability is remarkably improved and the productivity is improved.

[0088]

As described above, according to the present invention,
By providing the positioning holding member, the frame is not affected by the deformation and distortion generated when the frame is positioned and assembled, and the housing can be positioned reliably. Therefore, it is possible to prevent the irradiation position from being shifted and the number of man-hours required for assembling from increasing, and it is possible to ensure the compatibility of the housing in the market.

Further, by providing the position adjusting means, it is possible to easily and inexpensively cope with an accident itself such as a work error or an installation environment, and the reliability of the productivity in the factory, the serviceability in the market and the image quality. The performance is improved.

Further, since the positioning and holding portion is located in the vicinity of the vertical line with respect to the position on the predetermined surface where the light beam is condensed, it is possible to suppress the deviation of the irradiation position due to an error generated during assembly. Also, even when the adjustment is performed by the position adjusting means, the adjustment workability can be remarkably improved, and the productivity can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of an image forming apparatus according to an embodiment.

FIG. 2 is a detailed explanatory diagram of the laser scanner unit according to the present embodiment.

FIG. 3 is a schematic sectional view of a laser scanner unit according to the present embodiment.

FIG. 4 is a diagram showing a frame according to the present embodiment;
(A) is a schematic top view, (b) is a schematic sectional view.

5A and 5B are diagrams illustrating an adjustment method according to the present embodiment, wherein FIG. 5A is a schematic top view and FIG. 5B is a schematic cross-sectional view.

FIG. 6 is a schematic sectional view of a conventional image forming apparatus.

FIG. 7 is a detailed explanatory view of a conventional laser scanner unit.

FIG. 8 is a schematic sectional view of a conventional laser scanner unit.

FIG. 9 is a schematic view showing a conventional frame.

FIG. 10 is a schematic view of a laser scanner unit with a dust cover attached.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Image forming part 2 Cassette 3 Recording paper 4 Pickup roller 5 Separation part 6 Feeding conveyance part 7 Reversing guide part 8 Registration roller 9 Laser scanner 10 Photoreceptor drum 11 Developing part 12 Transfer part 13 Fixing part 14 Discharge conveyance part 15 Reversal Guide 16 Paper discharge roller 17 Paper discharge tray 18 Top sensor 19 Guide 20 Laser 21 Polygon motor 22 Optical lens group 23 Folding mirror 24 Optical box 25 Laser scanner stay (L) 26 Laser scanner stay (R) 27 Positioning pin (L) 28 Positioning pin (R) 29 Moving direction 30 Fixing screw 31 Positioning hole 32 Fixing screw 33, 34 Dust-proof lid 35 Positioning plate (L) 36 Positioning plate (R) 37 Loading surface of optical box 38 Writing position on drum 40 Front side plate 41 Rear side plate 42 Dora Axis hole 43 Positioning plate (R) fixing screw 44 Positioning plate (L) fixing screw 45 Frame adjustment jig 46 Jig positioning pin (L) 47 Jig positioning pin (R) 48 Positioning plate (L) positioning hole 49 Positioning plate (R ) Positioning hole 50 Positioning emboss and hole 51 Moving direction (up and down) 52 Laser scanner stay (R) adjustment hole 53 Positioning plate (R) adjustment hole 54 Negative hole 55 Fixing tap 56 Eccentric shaft

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H04N 1/113 H04N 1/04 104A 5C072 F term (Reference) 2C362 AA45 AA48 BA90 DA02 DA04 2H043 AB07 AB15 AB32 AB38 2H045 DA02 DA04 DA41 5C051 AA02 CA07 DB02 DB30 DB35 DC07 FA01 5C062 AA05 AB33 AD06 BA00 5C072 AA03 BA04 BA13 HA02 HA13 HA20 XA01 XA04

Claims (9)

[Claims] A light source unit; a deflection scanning unit that deflects and scans a light beam from the light source unit; an optical member that condenses a light beam deflected and scanned by the deflection scanning unit onto a predetermined surface; A scanning optical apparatus comprising: a housing to which the deflection scanning unit and the optical member are attached; and a positioning holding member fixedly supported by a frame of the apparatus main body and positioning and holding the housing to the frame. A scanning optical device, characterized in that: 2. The positioning and holding member is positioned and held together with the frame by a jig, and is held by holding means provided on the jig, and then the assembled frame is moved from the holding state by the holding means. 2. The scanning optical device according to claim 1, wherein after being released, the scanning optical device is fixedly supported by the frame. 3. The scanning optical apparatus according to claim 1, further comprising a position adjusting means for moving the positioning holding member with respect to the frame. 4. The position adjusting means includes a concave portion provided on the positioning and holding member and the frame, respectively, and a fixture fitted to the concave portion provided on the positioning and holding member and the frame, respectively. The scanning optical device according to claim 3, wherein the positioning and holding member is moved with respect to the frame by moving the tool. 5. A first positioning and holding unit provided on said positioning and holding member for positioning and holding said housing, wherein said first positioning and holding unit is located at a position on said predetermined surface at which a light beam deflected and scanned by said deflection scanning means is converged. The scanning optical device according to claim 1, wherein the scanning optical device is positioned near a vertical line. 6. The positioning and holding member, wherein the first positioning and holding portion of the at least two positioning and holding portions positions and holds the housing in a swingable manner, and the first positioning and holding portion is configured to control the deflection scanning. Means for positioning the light beam deflected and scanned by the means so as to be located in the vicinity of the vertical line with respect to the position on the predetermined surface where the light flux condensed is scanned, and the position adjusting means is provided with the first positioning and holding portion as a swing center for the frame. 5. The oscillating body is swung with respect to a body.
3. The scanning optical device according to claim 1. 7. The housing includes two positioning portions, the positioning and holding members are provided for the two positioning portions of the housing, respectively, and the first positioning and holding member of the positioning and holding members is A first positioning and holding unit for swingably positioning and holding the housing, and the first positioning and holding unit at a position on the predetermined surface where a light beam deflected and scanned by the deflection scanning unit is collected. The second positioning and holding member is pivoted by the position adjusting means with the housing with respect to the frame with the first positioning and holding portion as a pivot center. The scanning optical device according to claim 3, wherein the scanning is performed. 8. The positioning and holding member is positioned such that the first positioning and holding portion is positioned near a vertical line substantially at a center position in a scanning direction of a light beam condensed on the predetermined surface. The scanning optical device according to claim 5, 6 or 7, wherein 9. The scanning optical device according to claim 1, further comprising: an image carrier as the predetermined surface, wherein the electrostatic optical device is formed on the image carrier by the scanning optical device. An image forming apparatus, comprising: an image forming unit configured to transfer a toner image obtained by developing a latent image to a recording material.