JP2000241736A - Optical box - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an optical box capable of accurately measuring the relative positional relation of optical parts attached to the front side and the rear side of the inside of the optical box. SOLUTION: Shafts 28 (28a to 28c) are provided to project from at least three points on the outer wall of this optical box 11. A plane set by the center parts of the respective shafts 28 is set as reference in the case of fixing the optical box 11 on a surface plate 22 and measuring the attaching position of an fθ lens 14 on the front side. Meanwhile, the plane set by the center parts of the shafts 28 is similarly set as the reference in the case of measurement when the optical box 1 is inverted and fixed on the surface plate 22 and the attaching position of a cylinder mirror 20 on the back side is measured. Therefore, the measurement reference is made common in the measurement, so that the relative positional relation between the lens 14 and the mirror 20 is accurately measured.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical box of an optical scanning device used for a digital copying machine, a laser printer, and the like, and more particularly, to an optical box having optical components mounted on the front and back surfaces.

[0002]

2. Description of the Related Art Conventionally, many optical scanning devices used in copiers, laser printers and the like use laser light as a means for forming an electrostatic latent image on a photosensitive member. And
In order to respond to recent demands for higher speed and higher image quality, a so-called overfilled type that irradiates the rotating polygonal mirror with laser light whose width in the direction corresponding to the main scanning direction is larger than the area of the rotating polygonal mirror has been adopted. ing.

[0003] This type of optical scanning device is characterized in that a long optical path is folded back by a plurality of mirrors and optical components are accommodated in an optical box as small as possible in order to reduce the size of the optical scanning device. For this reason, the optical components inside the optical box may be arranged on the front side and the back side with respect to the mounting board of the optical box. That is, as shown in FIG. 7, the polygon mirror 12, each lens 14, the reflection mirror 16, and the like are arranged on the front side from the mounting substrate 18, and the photosensitive member (not shown) is irradiated with laser light from the mounting substrate 18 to the rear side. The configuration is such that a cylinder mirror 20 is disposed.

When measuring the accuracy of the components of the optical box, first, as shown in FIG. Using a dimension measuring machine 38, the mounting positions of the lenses 14 and the reflection mirror 16 arranged on the front side of the optical box 10 are
7B, the back of the leg 26 is fixed to the block 24 with the optical box 10 on the back, and the back of the leg 26 on the basis of the back L2 as shown in FIG. Is measured for the mounting position of the cylinder mirror 20 disposed at the position.

[0005]

However, in the above-mentioned measuring method, the thickness of the leg portion 26 varies, and
The measurement standards do not match, the dimensions from the measurement standards, and the mounting positions of the optical components on the front and back sides cannot be accurately measured, and each lens 14 and reflection mirror 18 on the front side and the cylinder mirror 20 on the back side cannot be measured. There is a problem that the relative positional relationship cannot be accurately known.

Accordingly, the present invention has been made to solve the above problem, and an optical box capable of accurately measuring a relative positional relationship between optical components disposed on the front side and the back side inside the optical box. The task is to provide.

[0007]

The optical box according to the present invention is an optical box having optical components mounted on the front and back surfaces thereof, and the mounting portion of the optical box is fixed to a jig and measured by a measuring machine. It is possible to turn over the optical box, fix the mounting portion of the optical box to the jig, and provide a common measurement site on the side wall that can be measured by the measuring machine.

[0008] According to this configuration, the optical components are mounted inside the front and back surfaces of the optical box, respectively. The optical box has its mounting portion fixed to a jig when measuring the mounting position of the optical component. In addition, this optical box can be measured with a measuring machine when the optical box is fixed to a jig to measure the optical parts on the front side, and the optical box is turned upside down to measure the mounting position of the optical parts on the back side. There is provided a common measurement site that can be measured by the measuring machine when fixed to the fixture.

For this reason, when measuring the mounting position of the optical component on the front side and the mounting position of the optical component on the back side, the above-mentioned measurement site can be used as a common measurement reference, and the optical components mounted on the front side and the back side can be measured. The relative positional relationship can be accurately measured.

Also, as in the invention described in claim 2,
Preferably, the measurement site is a shaft protruding from at least three places on the outer wall of the optical box.

Also, as in the invention according to claim 3,
Preferably, the measurement site is a hole formed in at least three places on the outer wall of the optical box.

Further, as in the invention described in claim 4,
It is preferable that a surface connecting the cores of the shafts or a surface connecting the cores of the holes is parallel to a mounting surface of the mounting portion fixed to the jig.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an optical box according to an embodiment of the present invention will be described with reference to the accompanying drawings.

As shown in FIG. 1, an optical box 1 of the optical scanning device is provided.
A cylindrical shaft 28 is integrally formed at three places on the outer wall of the optical box 1. In FIG. 1A, the shaft 28A is on the back surface N1 of the optical box 11, the shaft 28B is on the right side N2, and the shaft 28C is on the left side. It is located on each of the surfaces N3. Hereinafter, the shaft 28 is appropriately abbreviated.

As shown in FIGS. 1B and 1C,
The distances (distances in the Y direction) from the upper surface or the lower surface of the optical box 11 to the respective axes 28 are different from each other, and the distance difference between the centers of the shafts 28B and 28C (hereinafter, referred to as a dimensional difference S1) and the shaft 28A are different. Distance difference between the center and the axis 28C (hereinafter, referred to as
Dimension difference S2). Therefore, the dimensional difference S3 between the shaft 28A and the shaft 28B is the sum of the dimensional difference S1 and the dimensional difference S2, as shown in FIG.

The right side N2 and the left side N
3, a plurality of flanges 32 for fixing to a block 30 described later are formed (omitted in FIG. 1A).

On the other hand, an optical system is arranged inside the optical box 11, and in FIG. 1, as an example of the optical system, a polygon mirror 12 for scanning and deflecting a laser beam from a laser light source, an fθ lens 14, Cylinder mirror 20
Etc. are shown. Among these optical systems, the polygon mirror 12 and the fθ lens 14 are arranged on the front side inside the optical box 11 and
Is arranged on the back side inside the optical box 11.

Next, a description will be given of a method for measuring the mounting positions of the optical components arranged on the front side and the optical components arranged on the back side of the optical box.

When measuring the mounting position of the fθ lens 14 disposed on the front side of the optical box 11, first, a block 30 is mounted and fixed on the surface plate 22, and the optical box 11 is formed on the block 30. Place the flange 32 on the
4) (through 4).

Next, as shown in FIG. 3 and FIG.
The tentacle 39 of the three-dimensional measuring device 38 is moved in the X direction, the Y direction, or the Z direction (a direction perpendicular to the drawing), and the optical box 11 is moved.
Are measured at any three points on the outer peripheral surface of the shaft 28A provided on the side wall. Then, the center coordinates (core) of the axis 28A are obtained from the measurement results of these three points.

This measurement is sequentially performed for the remaining axes 28B and 28C, and the center coordinates (core) of each axis 28 are obtained. Even if the center coordinates of each axis 28 or each hole 41 are deviated from the target position on the drawing, the same thing (each axis 28 or each hole 41) in measuring the front and back of one optical box 11
Is used as a measurement reference, so that the relative position can be accurately measured.

Here, since the respective axes 28 are formed with the dimensional differences S1 to S3 in the optical box 11, the plane determined by the three central coordinates is the optical box 11 as shown in FIG.
Of the flange 34 (see FIG. 1B).

Therefore, in order to facilitate measurement of the mounting position of the fθ lens 14 or the like, for example, the shaft 28B is fixed and the shaft 2B is fixed.
By subtracting the dimensional differences S1 and S2 from the respective center coordinates of the axis 8C and the axis 28A, the plane is assumed to be a plane parallel to the mounting surface L3, and is set as a reference plane.

When the reference plane is set, the vertical distance from the reference plane to the mounting position of the fθ lens 14 is measured by the three-dimensional measuring device 38.

Next, in order to measure the mounting position of the cylinder mirror 20 arranged on the back side of the optical box 11, the optical box 11 is measured.
Is once removed from the block 30, and as shown in FIG.
After that, the optical box 11 is attached to the block 30 again and fixed.

Similarly, the point of the axis 28 is measured by the three-dimensional measuring device 38 in the same manner as when measuring the front side fθ lens 14 on the optical side 11, and the center coordinates (core) of each axis 28 are determined. Ask for each. Then, considering the dimensional differences S1 and S2 between the shafts 28, the flange 3 of the optical box 11 is used.
Set a reference plane parallel to the mounting surface of No. 2. This gives f
A reference plane serving as a reference when measuring the mounting position of the θ lens 14 and a reference plane serving as a reference when measuring the mounting position of the cylinder mirror 20 can be a common reference plane.

Thereafter, the vertical distance from the reference plane to the mounting position of the cylinder mirror 20 is measured in the same manner.

As described above, the optical box 11 can be measured by the three-dimensional measuring device 38 when the optical box 11 is fixed to the block 30 in order to measure the front side fθ lens 14, and the cylinder on the back side can be measured. Since the common shaft 28 that can be measured by the three-dimensional measuring device 38 when the mirror 20 is turned upside down and fixed to the block 30 to measure the mounting position of the mirror 20 is provided, the mounting position of the fθ lens 14 and the cylinder mirror 20 are measured. The mounting position can be measured from the common shaft 28, and fθ
The relative positional relationship between the lens 14 and the cylinder mirror 20 can be accurately measured.

By setting the measurement reference to each of the shafts 28 protruding from at least three places on the outer wall of the optical box 11, one plane can be formed. Measurement becomes easy.

Next, an example of a method for measuring the mounting position of an optical component according to one embodiment will be described.

In this embodiment, as shown in FIGS. 5 and 6,
Dimensional differences S1 to S between shafts 28 formed on optical box 13
This is an embodiment in which 3 is not provided.

According to this embodiment, first, the fθ lens 14
The optical box 13 is fixed to the block 30 on the surface plate 22 in order to measure the mounting position of. Then, the three-dimensional measuring machine 38 is moved to measure three outer peripheral surfaces of each shaft 28, and each shaft 28 is measured.
The center coordinates (core) of 8 are obtained. One plane is set from the obtained three center coordinates. This plane is for each axis 2
8 is formed in the optical box 13 without providing the dimensional differences S1 to S3, the reference plane H parallel to the mounting surface of the flange 32 of the optical box 13 can be provided.

Then, the vertical distance from the reference plane H to the mounting position of the fθ lens 14 is measured by the three-dimensional measuring device 38.

Next, when measuring the mounting position of the cylinder mirror 20 disposed on the back side inside the optical box 13, the optical box 13 is inverted and fixed to the surface plate 22. Then, similarly, the three-dimensional measuring device 38 is moved to measure three outer peripheral surfaces of each shaft 28, and the center coordinates (core portion) of each shaft 28 are obtained. A reference plane H parallel to the mounting surface of the flange 32 of the optical box 13 is set from the three center coordinates thus obtained.

Thereafter, the vertical distance from the reference plane H to the mounting position of the cylinder mirror 20 is measured by the three-dimensional measuring device 38.

As described above, since there is no dimensional difference between the shafts 28, the center coordinates of the three points constituting the reference surface H are on a plane parallel to the mounting surface L3 of the flange 32 of the optical box 13. As a result, the center coordinates can be easily obtained. Further, there is no need to consider the dimensional differences S1 to S3, and the reference plane H can be easily set.

It is sufficient that the shaft 28 is formed in at least three places. Further, the optical box 11 is not limited to the shaft 28 but may be replaced with the shaft 28 as shown in FIG.
Holes 41 may be formed in at least three places on the outer wall of the. In this case, the three-dimensional measuring device 38 measures three locations on the outer periphery of the hole 41 to determine the center coordinates (core). By forming a hole 41 in place of the shaft 28, the optical box 1
The external protrusion of the third can be eliminated.

[0038]

According to the optical box of the present invention, the optical box can be measured by a measuring device when the optical box is fixed to a jig for measuring the optical components on the front side, and the optical box on the rear side can be measured. There is a common measurement site that can be measured with a measuring machine when it is turned upside down and fixed to a jig to measure the mounting position of the optical component, so the mounting position of the front optical component and the mounting of the rear optical component The position can be measured from a common measurement standard, and the relative positional relationship between the optical components mounted on the front side and the back side can be accurately measured.

[Brief description of the drawings]

1A is a plan view showing an optical box according to an embodiment of the present invention mounted on a surface plate, FIG. 1B is a front view thereof, and FIG. 1C is a side view thereof. is there.

FIG. 2 is a side view of a state where the optical box of FIG. 1 is inverted and attached to a surface plate.

FIG. 3 is a partial configuration diagram of a three-dimensional measuring machine.

4A is a state diagram when measuring an axis formed in an optical box by a three-dimensional measuring machine, and FIG. 4B is a diagram when measuring a hole formed in an optical box by a three-dimensional measuring machine. FIG.

FIG. 5A is a front view of an optical box according to an embodiment of the present invention mounted on a surface plate, and FIG. 5B is a side view thereof.

FIG. 6 is a side view of a state where the optical box of FIG. 5 is inverted and attached to a surface plate.

FIG. 7A is a diagram showing an optical box fixed to a jig when measuring an optical component placed on the front side of the optical box, and FIG. 7B is a view showing the optical component placed on the back side thereof. FIG. 4 is a diagram showing an optical box fixed to a jig when measuring the optical box.

[Explanation of symbols]

 11, 13 Optical box 14 fθ lens (optical part) 22 Surface plate (jig) 20 Cylinder mirror (optical part) 28 Axis (measurement part) 30 Block (jig) 32 Flange (mounting part) 38 3D measuring machine ( Measuring machine) 41 holes (measuring site) S1, S2, S3 Dimension difference H Reference plane

Claims (4)

[Claims] 1. An optical box in which optical components are mounted on the front and back surfaces, respectively, wherein the optical box is fixed to a jig and can be measured by a measuring machine. An optical box, characterized in that a common measurement site which can be measured by a measuring machine by fixing the mounting portion is provided on a side wall. 2. The optical box according to claim 1, wherein the measurement site is a shaft protruding from at least three places on an outer wall of the optical box. 3. The optical box according to claim 1, wherein the measurement site is a hole formed in at least three places on an outer wall of the optical box. 4. A surface connecting the cores of the shafts or a surface connecting the cores of the holes is parallel to a mounting surface of the mounting portion fixed to a jig. Item 2 or 3
Optical box according to the above.