JPH11133336A - Scanning optical device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To hermetically seal the drawing-out port of a cable connected to the motor of a rotary polygon mirror. SOLUTION: The motor rotating the rotary polygon mirror 3 is electrically connected to a controller arranged outside an optical box 10 by the cable 13. The drawing-out port 10a of the cable 13 is constituted of a pair of slits 10c formed at the circumferential wall of a recessed part 10b formed at the side wall of the box 10. By pushing an elastic material 14 in the recessed part 10b, the port 10a is hermetically sealed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scanning optical device used for an image forming apparatus such as a laser beam printer and a laser facsimile.

[0002]

2. Description of the Related Art As shown in FIG. 7, a scanning optical device used in an image forming apparatus such as a laser beam printer or a laser facsimile collimates a laser beam generated from a semiconductor laser 101 by a collimator lens 102a.
After adjusting the beam shape by the aperture 102b, the beam is condensed into a linear light beam by the cylindrical lens 102c, and a predetermined direction (Y axis) perpendicular to the direction along the rotation axis (Z axis direction) by the rotary polygon mirror 103. Direction) and scans the rotating drum 10 through the imaging lens system 104.
5 on the photoreceptor. The light flux that forms an image on the photoconductor is
An electrostatic latent image is formed by main scanning in the Y-axis direction by rotation of the rotating polygon mirror 103 and sub-scanning in the Z-axis direction by rotation of the rotating drum 105.

In this manner, scanning for writing image information on the photosensitive member of the rotating drum 105 is repeated, but the writing position on the rotating drum 105 may be shifted due to a division error of the reflection surface of the rotating polygon mirror 103. There is. Therefore, the scanning light L ₀ of the rotating polygon mirror 103 is transmitted to the scanning plane (X
At one end in the Y-axis direction (Y plane), the signal detection mirror 10
6, the light is separated below the scanning surface by the condensing lens 1
The signal is introduced into the signal detection sensor 107 via the line 06a, converted into a scanning start signal by a controller (not shown), and transmitted to the semiconductor laser 101. The semiconductor laser 101 starts write modulation after receiving the scanning start signal.

The imaging lens system 104 includes a spherical lens 104
a and the toric lens 104b, and the rotating polygon mirror 1
03 has a so-called fθ function of converting the scanning light L ₀ scanned at a constant angular velocity into the scanning light that scans on the rotating drum 105 in the Y-axis direction at a constant velocity.

[0005] A semiconductor laser 101, a cylindrical lens 102c, a rotary polygon mirror 103, an imaging lens system 104,
The signal detection mirror 106, the signal detection sensor 107, and the like are attached to a side wall or a bottom wall of an optical box (not shown). Rotating drum 105 is disposed outside the optical box, the like the side wall of the optical box, rotary drum 10 scan light L ₀ from the optical box
A window for taking out toward 5 is provided. After assembling the optical components and the like in the optical box, the opening of the optical box is closed with a lid member.

A motor 1 for rotatingly driving the polygon mirror 103
Numeral 03a includes a drive circuit mounted on a motor substrate supported on the bottom wall of the optical box, and a magnetic circuit including a stator excited by a drive current of the drive circuit, a rotor opposed thereto, and the like.

[0007]

However, according to the above prior art, even if the opening of the optical box is closed by the lid member as described above, a motor for driving the rotary polygon mirror in the optical box, a signal detection sensor, etc. If a drawer such as a hole or a gap for pulling out a cable for electrically connecting the cable to an external controller etc. is left open, when the rotating polygon mirror is rotated, outside air will be sucked into the optical box and floating Dust adheres to the reflecting surface of the rotating polygon mirror and the lens surface of the imaging lens system.

When the optical components such as the rotary polygon mirror and the imaging lens system are contaminated by the outside air flowing into the optical box, the optical characteristics are deteriorated and the image quality is reduced, so that the maintenance cost is increased. Or the life of the device is shortened. In recent years, the speed of the scanning optical device has been increased, and the rotation speed of the rotary polygon mirror has tended to further increase. However, as the rotation speed of the rotary polygon mirror increases, the amount of outside air sucked into the optical box also increases. .

The present invention has been made in view of the above-mentioned unresolved problems of the prior art, and has a cable for electrically connecting a motor or a signal detection sensor of a rotary polygon mirror in an optical box to an external controller or the like. High-performance scanning suitable for high-speed operation, which effectively seals the draw-out opening for drawing out, prevents contamination of rotating polygon mirrors and lenses due to dust from the outside air, maintains maintenance-free, and maintains good image quality for a long time It is an object to provide an optical device.

[0010]

In order to achieve the above object, a scanning optical device according to the present invention comprises a deflecting means for converting a light beam generated from a light source into a scanning light, and applying the scanning light to a photosensitive member. An image forming means for forming an image, an optical box containing the deflecting means and the image forming means, a control means provided outside thereof, and an electric box for electrically connecting a driving means of the deflecting means to the control means. Connecting means, and an elastic material for sealing a draw-out opening provided in the optical box for pulling out the connecting means, wherein the optical box includes a recess for holding the elastic material; Characterized in that the outlet is provided on the peripheral wall.

[0011] Further, deflection means for converting a light beam generated from a light source into scanning light, imaging means for forming an image of the scanning light on a photosensitive member, and detecting a part of the scanning light as a scanning start signal. Signal detecting means, an optical box containing the deflecting means, the imaging means, and the signal detecting means, a control means disposed outside the optical box, and an electric connection between the control means and the signal detecting means. A connection means, and an elastic material for sealing a draw-out port provided in the optical box for extracting the connection means, wherein the optical box has a recess for holding the elastic material. The scanning optical device may be characterized in that the outlet is provided on the peripheral wall of the place.

Preferably, the connection means is sandwiched between the bottom surface of the recess of the optical box and the elastic material.

[0013] The connecting means may be sandwiched by cuts made of an elastic material held in the recesses of the optical box.

Alternatively, two elastic members may be held in the concave portion of the optical box, and a connecting means may be held between the two elastic members.

[0015]

The optical box is provided with a draw-out port for drawing out a cable or the like for electrically connecting the motor or the like of the rotary polygon mirror to an external controller or the like. The outside air enters and the rotating polygon mirror and the image forming means are contaminated. Therefore, a recess is provided on the side wall or the like of the optical box, the outlet is provided on the peripheral wall, and an elastic material for sealing the recess is pushed into the recess, so that the bottom of the recess and the elastic material The connecting means is sandwiched between them. Alternatively, the connection means may be sandwiched between cut portions provided in the elastic material, or the connection means may be sandwiched between two elastic materials.

Since the draw-out port can be sealed in a state where the elastic material is compressed and brought into close contact with the connection means, the outside air entering the optical box from the draw-out port is completely shut off, and the dust-proof effect of the optical box is greatly reduced. Can be improved.

[0017]

Embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows a scanning optical device according to a first embodiment, in which a laser beam L _1, which is a light beam emitted from a semiconductor laser 1 as a light source, is a collimator lens 1.
The light is collimated by a, is condensed into a linear light beam by the cylindrical lens 2, and is incident on the reflection surface of the rotary polygon mirror 3, which is a deflecting means. The reflected light is deflected and scanned by the rotation of the rotary polygon mirror 3, and is scanned in the Y-axis direction (main scanning direction).
, And forms an image on a photoreceptor on a rotating drum (not shown) via an imaging lens system 4 serving as an imaging means and a return mirror 5. The light beam that forms an image on the photoreceptor forms an electrostatic latent image with the main scanning in the Y-axis direction by the rotation of the rotary polygon mirror 3 and the sub-scanning in the Z-axis direction by the rotation of the rotating drum.

In the periphery of the photoreceptor, a charging device for uniformly charging the surface of the photoreceptor, a visualization device for visualizing an electrostatic latent image formed on the surface of the photoreceptor into a toner image, A transfer device or the like for transferring the toner image to a recording medium such as recording paper is provided, and by these operations, recording information corresponding to the light beam generated by the semiconductor laser 1 is printed on recording paper or the like.

The scanning light of the rotary polygon mirror 3 reaches one end of the scanning surface and is reflected by the signal detecting mirror 6.
The light is introduced into the signal detection sensor 7 through the condenser lens 7 a, converted into a scan start signal by the controller 8, which is control means provided outside the optical box 10, and transmitted to the semiconductor laser 1. After receiving the scanning start signal, the semiconductor laser 1 starts writing modulation based on image information transmitted from the host computer of the apparatus.

The semiconductor laser 1, the cylindrical lens 2, the rotating polygon mirror 3, the imaging lens system 4, the signal detection mirror 6, the signal detection sensor 7, etc. are mounted on the side and bottom walls of the optical box 10. The rotating drum is disposed outside the optical box 10, and the scanning light is applied to the bottom wall of the optical box 10.
A window 11 is provided for taking out from the rotating drum toward the rotating drum. The upper opening of the optical box 10 is closed by a lid member 20 shown in FIG. 3, and the lid member 20 is screwed to the optical box 10 at a peripheral edge thereof.

The imaging lens system 4 comprises a spherical lens 4a and a toric lens 4b, and converts scanning light scanned at a constant angular velocity by the rotating polygon mirror 3 into scanning light scanning at a constant speed in the Y-axis direction on the rotating drum. It has a so-called fθ function for conversion.

When assembling the optical box 10 to the main body frame of the scanning optical apparatus, first, positioning pins 9a, 9b of a positioning unit that engage with guide holes provided in the support portions 12a, 12b outside the optical box 10. Thus, the optical box 10 is positioned in the X-axis direction (optical axis direction) and the θ-axis direction (rotation angle). Positioning in the X-axis direction
The rotation is performed by moving the positioning pins 9a and 9b in the same direction in the X-axis direction with respect to the guide hole.
9b by moving them in opposite directions. After adjusting the relative position with respect to the photoconductor in this manner, the optical box 10 is fixed to the main body frame.

A motor 3a as a driving means of the rotary polygon mirror 3
As shown in FIG. 3, the magnetic circuit is composed of a stator 3c excited by a drive current of a drive circuit of a motor board 3b supported on the bottom wall of the optical box 10 and a magnetic circuit including a rotor 3d opposed thereto. .

An electric signal for controlling the above driving circuit is transmitted from a controller 8 disposed outside the optical box 10 via a cable 13 as connection means. The optical box 10 is provided with a draw-out port 10a for pulling out the cable 13 from the optical box 10. However, if this is left open, outside air flows in and the inside of the optical box 10 is contaminated by dust or the like. Therefore, the drawer port 10a is
(See FIG. 2).

The elastic member 14 is inserted into the recess 10b having a rectangular cross section provided on the side wall of the optical box 10 while being elastically compressed. The concave portion 10b of the optical box 10 has a flat bottom surface and a peripheral wall surrounding the flat bottom surface, and an outlet 10a for pulling out the cable 13 from the inside of the optical box 10 is substantially formed in the peripheral wall of the concave portion 10b. And a pair of slits 10c.

At the time of assembling the elastic member 14, the cable 13 is fitted into the slit 10c of the recess 10b of the optical box 10, and the elastic member 14 is pressed into the recess 10b while being compressed. Cable 13 to recess 1
0b. After the cable 13 is thus sandwiched between the elastic member 14 and the bottom surface of the recess 10b, the elastic member 14 is compressed from above when the lid member 20 is attached to the optical box 10. As described above, the elastic member 14 is airtightly filled in the recess 10b of the optical box 10 and the elastic member 14 is brought into close contact with the cable 13, so that the outlet 10a of the cable 13 is completely sealed, thereby preventing outside air from entering. Can be.

In the scanning optical device according to the present embodiment, the outlet for extracting the cable from the optical box can be completely sealed by the compressed elastic material.
Dust and the like do not enter the optical box from the outlet, and therefore, maintenance-free and high image performance can be maintained for a long time.

In addition, since the assembly of the elastic member is only required to press the elastic member into the concave portion of the optical box while compressing it, the operation is extremely simple, and can greatly contribute to the reduction of the assembly cost of the apparatus.

FIG. 4 shows a first modification of the first embodiment. This is because the bottom of the recess 10b of the optical box 10 and the elastic material 1
4 instead of inserting the cable 13 between the optical boxes 10
Elastic members 34a, 34 pushed into the recess 10b
The cable 13 is sandwiched between b. The elastic members 34a, 34b are assembled by pushing one elastic member 34a into the recess 10b, fitting the cable 13 into both slits 10c, and pushing the other elastic member 34b.

By sandwiching the cable between the two elastic members, the airtightness can be enhanced, and the dustproof effect of the optical box can be further enhanced.

FIG. 5 shows a second modification of the first embodiment. In this embodiment, a cutout portion 44a is provided near the center of the thickness of the elastic member 44 similar to the elastic member 14 according to the first embodiment, and the cable 13 is sandwiched therebetween.

In addition to being able to enhance the airtightness of the elastic material,
Compared with the case where two elastic members are used, the number of assembly parts is small and the assembly process is simple.

FIG. 6 shows a second embodiment. this is,
A draw-out opening 60a for pulling out a cable 63, which is a connection means for connecting a signal detection sensor 57, which is a signal detection means, to a controller, which is a control means (not shown), from an optical box 60 similar to the optical box 10 of the apparatus shown in FIG. Elastic material 64
Is to be sealed. A part of the scanning light of the rotating polygon mirror (not shown) is separated by the signal detection mirror 56 and introduced into the signal detection sensor 57 through the condenser lens 57a. The output of the signal detection sensor 57 is transmitted to the controller via the cable 63 and is converted into a scanning start signal.

A recess 60 b is provided in the side wall of the optical box 60, and an outlet 60 a through which the cable 63 is drawn out.
Is formed by a pair of slits 60c in the peripheral wall surrounding the recess 60b. To attach the elastic member 64, the cable 53 is fitted into both slits 60c and the elastic member 64 is inserted into the recess 60b.
It is done by pushing it in. As in the first embodiment, the cable 63 is sandwiched between the elastic member 64 and the bottom surface of the recess 60b to seal the outlet 60a.

[0036]

Since the present invention is configured as described above, it has the following effects.

The drawer for electrically connecting the motor of the rotary polygon mirror and the signal detection sensor in the optical box to an external controller is completely sealed to prevent outside air from entering therethrough, thereby preventing dust from entering the optical box. To strengthen. As a result, a high-performance scanning optical device that can maintain good image quality without maintenance for a long time can be realized. By mounting such a scanning optical device, it is possible to greatly enhance the performance and speed of the image forming apparatus.

[Brief description of the drawings]

FIG. 1 is a schematic plan view showing a scanning optical device according to a first embodiment.

FIG. 2 is a partial plan view showing a main part of the apparatus of FIG.

FIG. 3 is a sectional view showing the apparatus of FIG. 2;

FIG. 4 is a sectional view showing a first modification.

FIG. 5 is a partial plan view showing a second modification.

FIG. 6 is a cross-sectional view showing a second embodiment.

FIG. 7 is a diagram illustrating a scanning optical device according to a conventional example.

[Explanation of symbols]

 Reference Signs List 1 semiconductor laser 3 rotating polygon mirror 3a motor 4 imaging lens system 5 folding mirror 6 signal detection mirror 7 signal detection sensor 8 controller 10, 60 optical box 10a, 60a outlet 10b, 60b recess 20 lid member 13, 63 cable 14 , 34a, 34b, 44, 64 Elastic material

Claims (5)

[Claims] 1. A deflecting means for converting a light beam generated from a light source into a scanning light, an imaging means for forming an image of the scanning light on a photosensitive member, and an optical box containing the deflecting means and the imaging means And control means disposed outside thereof, connection means for electrically connecting the drive means of the deflecting means to the control means, and a drawing port provided in the optical box for pulling out the connection means. A scanning optical device comprising an elastic material for sealing, wherein the optical box has a recess for holding the elastic material, and the outlet is provided on a peripheral wall of the recess. 2. A deflecting means for converting a light beam generated from a light source into a scanning light, an image forming means for forming an image of the scanning light on a photosensitive member, and detecting a part of the scanning light as a scanning start signal. Signal detecting means, an optical box containing the deflecting means, the imaging means, and the signal detecting means, a control means disposed outside the optical box, and an electric connection between the control means and the signal detecting means. A connection means, and an elastic material for sealing a draw-out port provided in the optical box for extracting the connection means, wherein the optical box has a recess for holding the elastic material. A scanning optical device, wherein the drawing port is provided on a peripheral wall of a place. 3. The scanning optical apparatus according to claim 1, wherein the connecting means is sandwiched between the bottom surface of the concave portion of the optical box and the elastic member. 4. The scanning optical device according to claim 1, wherein the connecting means is held between cuts made of an elastic material held in the recess of the optical box. 5. The scanning optical device according to claim 1, wherein two elastic members are held in the recess of the optical box, and a connecting means is sandwiched between the two elastic members.