JP2003270576A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain an image forming apparatus in which deviation in the irradiation position of a light beam is reduced by reducing the deflection of a mounting plate in the image forming apparatus provided with several optical scanners. <P>SOLUTION: Respective optical scanners 14A and 14B are arranged and are attached to a mounting plate 15 so that the center-of-gravity position CM of the optical scanners 14A and 14B is positioned in the vicinity of the side plate 13S of a main body frame 13. Since the deflection of the mounting plate 15 is reduced, the change of relative positional relation between the optical scanners 14A and 14B and a photoreceptor 38 is reduced, so that the deviation in the irradiation position of a laser beam LB on the photoreceptor 38 is reduced. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus having a plurality of optical scanning devices, and more specifically, to an image forming apparatus such as a so-called laser beam printer or digital copying machine.

[0002]

2. Description of the Related Art In recent years, there has been an increasing demand for high-speed, high-quality laser beam printers and digital copying machines. Therefore, as shown in FIGS. 11 and 12, in the image forming apparatus 312 (so-called laser beam printer, etc.),
A device including a plurality of optical scanning devices 314 (sometimes referred to as a tandem machine) has been proposed. That is, in this image forming apparatus 312, two optical scanning devices 314 having the same configuration are attached and fixed to the attachment plate 315 fixed to the main body frame 313.

By the way, conventionally, when two optical scanning devices 314 having the same structure are mounted on the mounting plate 315, the optical scanning devices 314 are mounted so that they are oriented in the same direction. In the optical scanning device 314, its center of gravity CM
However, since it is often near the optical deflector 316, if the optical scanning device 314 is mounted in the same direction, the center of gravity CM of one optical scanning device 314 will be near the center of the mounting plate 315. The mounting plate 315 sometimes bent. As shown in FIG. 13, when the mounting plate 315 bends, the optical scanning device 31
Since the posture of No. 4 also changes, there may occur a problem that the irradiation position of the laser beam LB on the photoconductor 338 is displaced.

In general, the optical scanning device 314 is fixed to the mounting plate 315 at a plurality of fixing points. The position of these fixing points also increases the bending of the mounting plate 315 and the above-mentioned light beam irradiation position. It sometimes caused a deviation.

[0005]

SUMMARY OF THE INVENTION In consideration of the above facts, an object of the present invention is to reduce the deflection of the mounting plate and the deviation of the irradiation position of the light beam in an image forming apparatus having a plurality of optical scanning devices. An object of the present invention is to obtain an image forming apparatus that can be used.

[0006]

According to a first aspect of the present invention, there is provided a main body frame, a mounting plate fixed to the main body frame, and an optical deflector for deflecting a light beam emitted from a light source according to image information. And a plurality of optical scanning devices including an imaging optical system that forms an image of the deflected light beam on the surface to be scanned, and the plurality of optical scanning devices are provided with It is characterized in that it is attached to the attachment plate so as to be located near a side surface of the main body frame.

Since this image forming apparatus is provided with a plurality of optical scanning devices, it is possible to form an image in multi-color or mono-color as required. In each optical scanning device, the light beam emitted from the light source is deflected by the optical deflector, and the deflected light beam is imaged on the surface to be scanned by the imaging optical system.

The plurality of optical scanning devices are mounted on the mounting plate such that the center of gravity of each of the plurality of optical scanning devices is located near the side surface of the body frame. As a result, the bending of the mounting plate is reduced, and the change in the attitude of the optical scanning device is also reduced. Therefore, it is possible to reduce the deviation of the irradiation position of the light beam emitted from each optical scanning device.

According to a second aspect of the present invention, in the first aspect of the invention, the optical deflector is disposed near a side surface of the optical scanning device, and the optical scanning device is disposed near a side surface of the main body frame. It is characterized in that it is attached to the attachment plate so as to be positioned.

Generally, the position of the center of gravity of the optical scanning device is often near the position of the optical deflector. In the image forming apparatus according to the second aspect, since the optical deflector is arranged near the side surface of the optical scanning device, the center of gravity of the optical scanning device is also near the side surface of the optical scanning device. The optical scanning device is attached to the mounting plate so as to be located near the side surface of the body frame, so that the center of gravity of the optical scanning device is attached to the mounting plate so as to be located near the side surface of the body frame.

According to a third aspect of the present invention, in the first or second aspect of the present invention, a plurality of photoconductors are respectively irradiated with the light beams deflected and imaged by the plurality of optical scanning devices, And the optical scanning device is arranged so that the light beam is vertically incident on the photoconductor.

As a result, it becomes possible to arrange the photosensitive members having the same structure in the image forming apparatus in the same direction.

According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, at least a part of each electric component of each of the plurality of optical scanning devices is attached to the main body frame. It is characterized in that it is arranged so as to concentrate in the vicinity of the interface board.

As a result, the distance from the interface board of the main body frame to the electric parts is shortened, so that wiring or the like can be performed at low cost. By shortening the wiring, it is possible to reduce noise that acts on the wiring.

According to a fifth aspect of the invention, in the invention according to any one of the first to fourth aspects, the plurality of optical scanning devices have the same deflection direction of the light beam by the optical deflector. It is characterized by being arranged as follows.

When the deflection direction of the light beam by the light deflector is the opposite direction, this shift becomes large if the writing position of the light beam is shifted. On the other hand, by setting the deflection directions of the light beams in the same direction as described in claim 5, the shift of the writing position also moves in the same direction.
It is possible to eliminate the relative positional deviation between the two light beams.

According to a sixth aspect of the present invention, a body frame, a mounting plate fixed to the body frame, an optical deflector for deflecting a light beam emitted from a light source according to image information, and a deflector are provided. A plurality of optical scanning devices including an image forming optical system for forming an image of a light beam on a surface to be scanned, the optical scanning device including three optical scanning devices near the side plate of the body frame with respect to the mounting plate. It is characterized by being attached at a fixed point.

Since this image forming apparatus is provided with a plurality of optical scanning devices, it is possible to form images in multi-color and mono-color as required. In each optical scanning device, the light beam emitted from the light source is deflected by the optical deflector, and the deflected light beam is imaged on the surface to be scanned by the coupling optical system.

The plurality of optical scanning devices are attached to the attachment plate at three fixing points near the side plates of the main body frame. Compared with a case where the optical scanning device is fixed at the central portion of the mounting plate, the mounting plate is less likely to bend, and therefore the posture of the optical scanning device is less changed. Therefore, it is possible to reduce the deviation of the irradiation position of the light beam emitted from each optical scanning device.

In the invention according to claim 7, in the invention according to claim 6, two of the three fixing points are arranged in the vicinity of a relatively high-rigidity portion of the main body frame. It is characterized by being.

As a result, the bending of the mounting plate can be further reduced.

[0022]

1 and 2 show a schematic structure of an image forming apparatus 12 according to an embodiment of the present invention.

The image forming apparatus 12 has a box-shaped or frame-shaped main body frame 13.
A mounting plate 15 is fixed inside. Two optical scanning devices 14A, 14 are mounted on the mounting plate 15.
B is fixed by the fixing portion 22, and it is possible to form a color image.

Each of the optical scanning devices 14A and 14B has a
In the housing 21, a laser beam light source 17 such as a laser diode, a collimator lens 26, a cylinder lens 28,
The optical deflector 16, the f-θ lens 30, and the cylinder mirror 32 are provided.

A wiring portion 34 is provided in the housing 21. The wiring portion 34 is the side plate 1 on the back side of the main body frame 13.
The laser beam light source 17 and the optical deflector 1 are connected to the interface board 36 attached to the 3R.
Wiring necessary for controlling 6 is provided. Therefore, according to the signal from the interface board 36, the laser beam light source 17 emits a laser beam and the optical deflector 16 is rotationally controlled.

Further, these optical scanning devices 14A, 14B
Corresponding to the above, the photoconductor 38 is disposed below the photoconductor 38, and a charging device 40, a developing device 42, and a cleaning device 44 are provided around the photoconductor 38 (note that the charging device 40, the developing device 40 in FIG. The device 42 and the cleaning device 44 are not shown).

In the image forming apparatus 12 of the first embodiment having such a configuration, the respective optical scanning devices 14A and 1A are provided.
4B, the laser beam light source 17 according to the image information
The laser beam LB emitted from is converted into a substantially parallel light beam by the collimator lens 26 and the cylinder lens 28, and is incident on the rotary polygon mirror 24 of the optical deflector 16. The rotary polygon mirror 24 is adapted to rotate at a constant speed, and the laser beam LB is deflected by this rotation.

At this time, as shown in FIG. 1, in the optical scanning devices 14A and 14B of the present embodiment, the optical deflector 16 is rotated in the opposite directions to thereby deflect the laser beam LB (main scanning direction). However, two optical scanning devices 14A,
14B, the same direction (arrow L direction) is set.

The deflected laser beam LB passes through the f-θ lens 30, is further reflected by the cylinder mirror 32, and is imaged on the photoconductor 38. Then, the electrostatic latent image formed on the photoconductor 38 becomes a toner image by the developing device 42 and is developed (visualized). This toner image is further transferred to a sheet on a transfer belt (not shown) to form an image on the sheet.

Here, the image forming apparatus 12 of the first embodiment.
Then, as can be seen from FIGS. 1 and 2, the optical scanning device 14
The optical scanning devices 14A and 14B are arranged so that the center of gravity (center of mass) CM of A and 14B is located near the side plate 13S of the main body frame 13, and the mounting plate 1 is mounted.
It is attached to 5. Generally, in an optical scanning device, the optical deflector 16 often has the largest mass, and even if the mass of each member other than the optical deflector 16 is taken into consideration, the position of the optical deflector 16 is set to the optical scanning devices 14A and 14B. In many cases, the position of the center of gravity of can be approximated. Therefore, in the present embodiment, the optical deflector 16 is positioned near the side plate 21S of the housing 21, and the one optical scanning device 14A is arranged so that the optical deflector 16 is positioned near the side plate 13S. Also, with respect to the other optical scanning device 14B, the mounting plate 1 is rotated in a direction in which the optical scanning device 14A is substantially rotated by 180 degrees about the vertical axis so that the optical deflector 16 is located near the side plate 13S.
It is attached to 5.

As a result, the bending force acting on the mounting plate 15 from the optical scanning devices 14A and 14B is also reduced by the side plate 13.
Acting in the vicinity of S, the mounting plate 15
Less bending. Since the changes in the postures of the optical scanning devices 14A and 14B are reduced and the changes in the relative positional relationship between the optical scanning devices 14A and 14B and the photoconductor 38 are also reduced,
The deviation of the irradiation position of the laser beam LB on the photoconductor 38 is also reduced.

In particular, in this embodiment, as can be seen from FIGS. 1 and 2, the optical deflector 16 of each of the optical scanning devices 14A and 14B is connected to the side plate 21 of the optical scanning devices 14A and 14B.
By arranging in the vicinity of S, the optical scanning devices 14A, 14B
The barycentric position CM is positively shifted from the centers of the optical scanning devices 14A and 14B. Then, the optical scanning devices 14A, 1
4B is arranged such that the center of gravity of these 4B is located in the vicinity of the side plate 13S, so that the bending force acting on the mounting plate 15 from the optical scanning devices 14A and 14B is applied to the side plate 13S.
So that the mounting plate 15 can be more securely prevented from bending.

The "vicinity" in the present invention means that the center of gravity CM of the optical scanning devices 14A and 14B is the optical scanning device 1.
4A, 14B is closer to any of the side plates 13F, 13R, 13S of the main body frame 13 than the center of the 4A, 14B in plan view.

Further, in the image forming apparatus 12 of the present embodiment, the optical scanning devices 14A, 14A, 14B are arranged so that the laser beams LB emitted from the respective optical scanning devices 14A, 14B are vertically incident on the photoconductor 38. 14B is arranged. As a result, the photoconductor 38 and the members (the charging device 40, the developing device 42, the cleaning device 44, etc.) around the photoconductor 38 can be made common in configuration, and those having the same configuration can be arranged in the same direction. ing.

Further, in the image forming apparatus 12 of the present embodiment, the deflection directions (main scanning directions) of the laser beams LB emitted from the respective optical scanning devices 14A and 14B are the same direction, so-called color shift. Is prevented.
This point will be described with reference to FIG.

FIG. 3 shows an image writing start position by the laser beam LB in a configuration using two optical scanning devices, and (A) shows an ideal position where the image writing start position is not displaced (B). ) And (C) are both cases where there is a deviation, (B) is the case where the deflection directions of the laser beam LB are the same as in the present embodiment, and (C) is the laser beam LB. This is the case where the deflection direction of is reversed (see FIG. 4). In each of (A), (B), and (C), the laser beams LB of the two optical scanning devices are shown as LB1 and LB2 by the upper and lower two lines. Further, a dashed line in the vertical direction indicates a position where the image writing start position of the laser beam LB is not displaced (hereinafter referred to as “reference position”).

In an ideal image forming apparatus, since the two laser beams LB are both at the reference position as shown in FIG. 3A, so-called color misregistration does not occur and a high quality image is formed. can do.

On the other hand, as shown in FIG.
When absolute deviations D1 and D2 from the reference position are generated in the laser beam LB of the book, if the deflection directions of the laser beam LB are opposite directions, the laser beams LB deviate in opposite directions. In the laser beam LB, the amount of misregistration is added and increased (D3), and color misregistration occurs.

On the other hand, as shown in FIG. 3B, when the laser beams LB are deflected in the same direction, each laser beam LB has an absolute deviation D1 from the reference position. Also, since the two laser beams LB are displaced by the same amount in the same direction, as a result, the relative displacement is eliminated. That is, in this embodiment, so-called color shift is reliably prevented.

Further, in the image forming apparatus 12 of the present embodiment, as shown in FIG.
It is attached to the housing 21 so as to be in the vicinity of the interface board 36 of the main body frame 13. Without using such a configuration, only two optical scanning devices 14A,
When 14B are arranged so that they are rotated about the vertical axis, the wiring portions 34 are in mutually opposite positions as shown in FIG. 4, so that the wiring portion 34 on one side (the optical scanning device 14A in FIG. 4) is an interface. Although located near the board 36, the other wiring portion 34 (the optical scanning device 14B in FIG. 4) is separated from the interface board 36. When the wiring portion 34 is separated from the interface board 36 in this way, more members (cord or the like) are required for wiring between the interface board 36 and the wiring portion 34, resulting in higher cost. In addition, noise from the outside world may act on the wiring between the interface board 36 and the wiring portion 34. In the present embodiment, both the wiring portions 34 of the two optical scanning devices 14A and 14B are located in the vicinity of the interface board 36, so that the wiring between them can be short and the cost can be reduced. Also, the influence of noise from the outside world can be reduced.

The electric parts arranged near the interface board 36 are not limited to the wiring part 34. That is, by disposing at least a part of the electric components constituting the optical scanning devices 14A and 14B in the vicinity of the interface board 36, wiring can be performed between the interface board 36 and the electric components at low cost, and
The influence of noise can be reduced.

In the above description, the two optical scanning devices 14A,
The image forming apparatus 12 including 14B has been described as an example, but the number of optical scanning devices forming the image forming apparatus is not particularly limited. For example, as shown in FIG. 5, the image forming apparatus 52 includes three optical scanning devices 14A, 14B, and 14C.
May be configured. Furthermore, it is of course possible to form an image forming apparatus with four optical scanning devices so that a so-called full-color image can be formed. When an odd number of optical scanning devices are arranged, as can be seen from FIG. 5, the central optical scanning device (in FIG. 5, the optical scanning device 1
4C) is arranged such that its center of gravity CM is close to one of the side plates 13, and other optical scanning devices (optical scanning devices 14A and 14B in FIG. 5) are
The barycentric positions CM may be arranged so as to be located nearer the side plates 13 that are closer to each other.

Further, in the above description, the position of the optical deflector 16 of each of the optical scanning devices 14A, 14B and 14C is set as the center of gravity CM, and the optical deflector 16 is arranged in the vicinity of the side surface of the housing 21. As shown in each of the embodiments, it is possible to determine the position of the center of gravity and also determine the arrangement of each of these members in consideration of the arrangement of other members constituting the optical scanning device.

For example, in the image forming apparatus 62 of the second embodiment shown in FIG. 6, the respective optical scanning devices 64A, 64 are provided.
A reflection mirror 66 is provided at B, and the laser beam LB deflected by the optical deflector 16 is reflected by the reflection mirror 66, then is reflected again by the cylinder mirror 32 and is incident on the photoconductor 38. Then, regarding each of the optical scanning devices 64A and 64B, the center of gravity CM is positioned near the side surface of the housing 21 in consideration of not only the optical deflector 16 but also the cylinder mirror 32 and the f-θ lens 30. (Therefore, the barycentric position CM shown in FIG. 6 is slightly displaced from the position of the optical deflector 16 unlike the barycentric position CM shown in FIG. 2).

The image forming apparatus 72 of the third embodiment shown in FIG. 7 is provided with two optical scanning devices 74A and 74B in which the positions of the respective members are different. That is, the optical scanning device 74A on the left side of the drawing has substantially the same configuration as the optical scanning device 64A shown in FIG.
In addition to the right side optical scanning device 74A, a plurality of reflection mirrors 76 are arranged, and the f-θ lens 30 is arranged at a position farther from the optical deflector 16. As a result, in the optical scanning device 74B, the position of the optical deflector 16 in the housing 21 is on the left side in the drawing as in the optical scanning device 74A, but its center of gravity CM is moved to the right side.
As described above, the position of the center of gravity CM can be set at a desired position in consideration of the positions of various optical components and members forming the optical scanning device.

Further, as an example of the configuration of the optical scanning device,
Various structures shown in FIGS. 8A to 8C can be given.

As shown in FIG. 8A, in the optical scanning device 84 according to the fourth embodiment, the light beam deflected by the optical deflector 16 is reflected by the reflection mirror 86 and then by the cylinder mirror 32, The laser beam LB is made to enter the photoconductor 38 from the back side of the optical deflector 16.

As shown in FIG. 8B, the optical scanning device 94 according to the fifth embodiment has the same members as the optical scanning device 84 shown in FIG.
By changing the direction of 2, the light beam is emitted diagonally upward,
The light is incident on the photoconductor 38 (therefore, it is arranged above the optical scanning device 94 of the photoconductor 38).

The optical scanning device 104 according to the sixth embodiment shown in FIG. 8C has the same members as the optical scanning device 84 shown in FIG. 8A, but the orientation of the cylinder mirror 32 is changed. By changing it, the light beam is irradiated downward from between the light deflector 16 and the f-θ lens 30 and is incident on the photoconductor 38.

Then, in each of the optical scanning devices 84, 94 and 104 of the respective embodiments shown in FIGS. 8A to 8C, the optical deflector 16, the cylinder lens 28 and the f-θ lens 30 are provided.
In addition to the collimator lens 26, the cylinder mirror 3
2 and the laser beam light source 17 and the like, they are arranged so that the center of gravity is located near the side surface of the housing 21. Therefore, the optical scanning devices 84, 94, 1
When the image forming apparatus is configured by using 04, it is possible to easily arrange the optical scanning devices 84, 94, 104 so that the center of gravity positions thereof are located near the side plate 13S (see FIG. 1) of the main body frame 13 ( For example, similarly to the first embodiment, it may be rotated about the vertical axis). This allows
The bending of the mounting plate 15 can be reliably prevented.

FIG. 9 shows the positions of fixing points 116A, 116B and 116C for fixing the optical scanning device 114 in the image forming apparatus 112 according to the seventh embodiment of the present invention.

The fixed points 116A, 116B and 116C are
Three optical scanning devices 114 are provided on the mounting plate 15. Two of the fixing points 116A and 116B are located near the rear side plate 13R of the main body frame 13, and one fixing point 116C is provided.
Is located in the vicinity of the side plate 13F on the front surface side of the main body frame 13. In general, since the periphery of the mounting plate 15 is fixed to the main body frame 13, even if a load is applied to the periphery, there is little bending. Image forming apparatus 1 of the seventh embodiment
In 12, the fixed points 116A, 116B, and 116C are all located in the vicinity of any of the side plates 13F, 13R, and 13S of the main body frame 13, so that the bending of the mounting plate 15 is reliably prevented. .

On the other hand, since the vicinity of the center of the mounting plate 15 is not fixed to the main body frame 13, it tends to bend when a load acts on the vicinity of the center. Therefore, for example, as shown in FIG. 10, fixed points 116A, 116B, 1
At least one of 16C (fixed point 116C in FIG. 10)
Is in a position other than the vicinity of the body frame 13, the load of the optical scanning device 114 acts on the vicinity of the center of the mounting plate 15, so that the mounting plate 15 is easily bent.

The fixed points 116A, 116B, 116
It suffices that each of the Cs is located in the vicinity of the side plate of the body frame 13, and their specific positions are not limited to the positions shown in FIG. 9. Thus, for example, fixed point 11
One of 6A, 116B and 116C is a side plate 13F on the front side.
1 may be located near the rear side plate 13R and one may be located near the lateral side plate 13S. Generally, since the rear side plate 13R and the front side plate 13F have high rigidity, as shown in FIG. 9, the fixing points 116A, 11 are provided near these high rigidity members.
Arranging 6B and 116C is more preferable because the bending of the mounting plate 15 can be more surely prevented.

Further, the image forming apparatus 112 of the seventh embodiment.
In the above, the specific configuration of the optical scanning device 114 that constitutes the image forming apparatus 112 is not particularly limited. That is,
Since the fixing points 116A, 116B, and 116C of the image forming apparatus 112 with respect to the mounting plate 15 are set as described above to prevent the mounting plate 15 from being bent, for example, light that has been commonly used in the past can be used. Even the scanning device can prevent the mounting plate 15 from bending. Of course, the optical scanning devices 14A (or 14B), 74A, 84A, and 94 according to the respective embodiments of the present invention.
A and 104A may be used, and in this case, the bending of the mounting plate 15 can be prevented more reliably, which is preferable.

[0056]

Since the present invention has the above-described structure, in an image forming apparatus having a plurality of optical scanning devices, it is possible to reduce the deflection of the mounting plate and the deviation of the irradiation position of the light beam.

[Brief description of drawings]

FIG. 1 is a partially cutaway perspective view showing a schematic configuration of an image forming apparatus according to a first embodiment of the present invention.

FIG. 2 is a partially cutaway front view showing the schematic configuration of the image forming apparatus according to the first embodiment of the present invention.

FIG. 3 is an explanatory diagram showing an image writing start position by a laser beam, where (A) shows no deviation, (B) shows deviation in the same direction, and (C) shows deviation in the opposite direction. This is the case.

FIG. 4 is an explanatory diagram showing a schematic configuration of an image forming apparatus having an optical scanning device in which wiring portions are arranged at positions opposite to each other.

FIG. 5 is a partially cutaway front view showing an example in which three optical scanning devices are provided in the image forming apparatus of the first embodiment of the present invention.

FIG. 6 is a partially cutaway front view showing an image forming apparatus according to a second embodiment of the present invention.

FIG. 7 is a partially cutaway front view showing an image forming apparatus according to a third embodiment of the present invention.

8A to 8C are a schematic front view and a schematic plan view showing an optical scanning device applicable to any of the image forming apparatuses of the fourth embodiment of the present invention.

FIG. 9 is a plan view showing a schematic configuration of an image forming apparatus according to a fourth embodiment of the present invention.

FIG. 10 is a plan view showing a schematic configuration of an image forming apparatus in which a fixed point of the optical scanning device is arranged near the center of a mounting plate.

FIG. 11 is a partially cutaway perspective view showing a schematic configuration of a conventional image forming apparatus.

FIG. 12 is a partially cutaway front view showing a schematic configuration of a conventional image forming apparatus.

FIG. 13 is an explanatory diagram showing a shift in irradiation position of a light beam on a photoconductor in a conventional image forming apparatus.

[Explanation of symbols]

12 Image forming apparatus 13 body frame 13R side plate 13S side plate 13F side plate 14A Optical scanning device 14B Optical scanning device 15 Mounting plate (mounting plate) 16 Optical deflector 17 Laser beam light source (light source) 21 housing 24 rotating polygon mirror 26 Collimator lens 28 cylinder lens 30 f-θ lens (imaging optical system) 32 cylinder mirror (imaging optical system) 34 Wiring part (electrical parts) 36 Interface board 38 photoconductor 52 image forming apparatus 62 image forming apparatus 64A optical scanning device 72 image forming apparatus 74A Optical scanning device 74B Optical scanning device 84 Optical scanning device 94 Optical scanning device 104 Optical scanning device 112 image forming apparatus 114 Optical scanning device 116A fixed point 116B fixed point 116C fixed point

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) G03G 15/01 112 G03G 15/04 111 15/04 111 B41J 3/00 DF term (reference) 2C362 BA50 BA90 DA02 DA03 2H045 BA22 BA34 CA92 DA04 2H076 AB05 AB12 AB18 AB22 EA01 EA16 EA18 2H171 FA01 FA03 FA05 FA12 FA28 GA01 GA32 HA02 HA22 JA05 JA15 KA05 KA06 KA23 MA02 MA03 MA07 MA20 QA04 QA06 QA08 QB15 QB17 QB32 QC05 TA05 TA19 WA06 WA13 WA16 WA17 WA21 WA23 2H300 EA01 EA06 EB04 EB07 EB12 EB24 EF06 EH16 EH26 EJ07 EK03 GG01 GG02 GG28 GG38 GG46 GG49 HH01 HH08 HH12 HH29

Claims (7)

[Claims] 1. A body frame, a mounting plate fixed to the body frame, an optical deflector for deflecting a light beam emitted from a light source according to image information, and the deflected light beam on a surface to be scanned. A plurality of optical scanning devices having an image forming optical system for forming an image on the optical system, wherein the plurality of optical scanning devices are mounted so that respective barycentric positions thereof are located near a side surface of the body frame. An image forming apparatus characterized by being attached to a plate. 2. The optical deflector is arranged near a side surface of the optical scanning device, and the optical scanning device is attached to the mounting plate so as to be located near a side surface of the body frame. The image forming apparatus according to claim 1. 3. A plurality of photoconductors, each of which is irradiated with a light beam that is deflected and imaged by the plurality of light scanning devices, so that the light beams are incident perpendicularly to the photoconductor. The image forming apparatus according to claim 1, wherein the optical scanning device is arranged. 4. The at least part of the electric components of each of the plurality of optical scanning devices is arranged so as to be concentrated in the vicinity of an interface board attached to the main body frame. The image forming apparatus according to claim 3. 5. The optical scanning device according to claim 1, wherein the plurality of optical scanning devices are arranged such that the deflection directions of the light beams by the optical deflector are the same. Image forming device. 6. A body frame, a mounting plate fixed to the body frame, an optical deflector for deflecting a light beam emitted from a light source according to image information, and the deflected light beam on a surface to be scanned. A plurality of optical scanning devices each having an image forming optical system for forming an image on the optical system, the optical scanning devices being attached to the attachment plate at three fixing points near a side plate of the body frame. An image forming apparatus characterized by the above. 7. The image forming according to claim 6, wherein two of the three fixing points are arranged in the vicinity of a relatively rigid portion of the main body frame. apparatus.