JPH10221620A - Optical scanner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an easily decomposable optical scanner excellent for a re-cyclable property. SOLUTION: Optical parts such as an fθ lens 42, etc., arranged in an optical box 46 in the optical scanner are pressurized and held by hold members 50, and are fixed by a wire 52 and a tensioner. That is, by adjusting tension applied to the wire 52 by the tensioner, the optical parts are fixed surely. Thus, the optical parts are taken off, and the optical scanner is decomposed only by performing simple work so as to weaken the tension applied to the wire 52. Further, since the parts aren't damaged at a decomposing time, respective parts are reused after cleaning, adjustment and exchange of consumption parts, etc., are performed, and the recyclable property is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical scanning device provided in an image recording apparatus such as a laser printer and a digital copying machine, and more particularly to an optical scanning device excellent in recyclability.

[0002]

2. Description of the Related Art Recent image recording apparatuses such as laser beam printers and digital copiers are provided with an optical scanning device for scanning a photosensitive material or a photosensitive member with a light beam.
The optical scanning device includes a plurality of optical components such as a collimator lens, a cylinder lens, a polygon mirror, an fθ lens, and a reflection mirror. These optical components are fixed to a predetermined position in an optical box, which is one of the forming components of the optical scanning device, using, for example, an elastic member or an adhesive.

For example, in the case of fixing using an elastic member, an optical component is arranged at a predetermined position of an optical box, pressed in this state by an elastic member, and screwed so as to maintain the pressed state (not shown). ) And the elastic member 100 are snap-fitted (smooth at the time of insertion, but difficult to remove due to the influence of frictional force, etc.) to the pin 103 formed on the optical box 102, and optically held by the holding portion 100 </ b> A of the elastic member 100 A method for fixing the component 104 (FIG. 11)
(A)). When an adhesive is used, the optical component 104 is arranged at a predetermined position of the optical box 106 as shown in FIGS.
Fix at 8.

[0004] In recent years, there has been a need for designing an optical scanning device in consideration of recyclability. Designs suitable for recycling include avoiding inseparable connections between dissimilar materials, such as by adhesion, and the presence of easily decomposable mechanical connections. However, when the optical component is fixed by the above-described means, the structure is difficult to be disassembled. For example, when the elastic member is screwed, screwing work in a narrow space is complicated, and especially when a tapping screw is used, it becomes impossible to reuse the optical box. When the snap fit is used, the elastic member 100
It is conceivable that the elastic member 100 is deformed when it is removed, so that the elastic member 100 cannot be reused or the pin 103 on the optical box 106 holding the elastic member 100 is broken.
Furthermore, when an adhesive is used, it is difficult to disassemble, and even if it is decomposed, there is a problem that it is difficult to reuse the adhesive because the adhesive remains attached.

[0005] As described above, the optical scanning device in which the optical components are fixed by the above-described means is designed to be difficult to adapt to recyclability. Therefore, in order to solve the above-mentioned problem, there is an optical unit for fixing an optical component with a cover (cover) of an optical box (Japanese Patent Laid-Open No. 3-233474).

As shown in FIGS. 12A and 12B, an optical box 110 of an optical unit includes a housing 112 and a lid 1.
14. The housing 11 is attached to the lid 114.
A concave pressing portion 118 is formed to press each of the optical components 116 arranged at the two predetermined positions from above. A screw 122 is used to close the opening of the housing 112 with the lid 114. As a result, the pressing portion 118 formed on the lid 114 comes into contact with the upper part of each optical component 116 to press and fix it. When the screw 122 is removed, the housing 112 and the lid 114 can be separated, and the optical unit (optical scanning device) can be easily disassembled.

[0007]

However, since the optical component 116 is pressed and fixed by the pressing portion 118 formed on the lid 114, a space cannot be formed above the optical component 116. As a result, the scanning direction of the light beam emitted from the light source is limited, and it is difficult to form a three-dimensional optical layout.

In view of the above, the present invention provides an optical scanning apparatus which can form a three-dimensional optical layout without increasing the size of the apparatus and which can be easily disassembled and has excellent recyclability. With the goal.

[0009]

According to the first aspect of the present invention, there is provided an optical component for converging a light beam emitted from a light source to form an image on a surface to be scanned, and a predetermined position. A detachable holding member for holding the optical component disposed in the vicinity by elastic force, and a scanning space of the light beam are hooked on the holding member in a region partitioned from the holding member to prevent the holding member from falling off. Locking means.

According to the first aspect of the present invention, the optical scanning device is provided with an optical component. As optical components,
For example, there are a collimator lens, a cylinder lens, a polygon mirror, an fθ lens, a reflection mirror, and the like. The light beam emitted from the light source is focused to form an image on a surface to be scanned such as a photoconductor. Further, the optical components provided in the optical scanning device are held by a detachable holding member having an elastic force. As the holding member, for example, a leaf spring or a coil spring is used. Further, the optical scanning device is provided with a locking means for preventing a holding member for holding the optical component from falling off. At this time, the locking means is locked to the holding member in a region separated from the scanning space of the light beam emitted from the light source. For example, when arranging the optical component in the optical box, a part of the holding member is protruded to the back side of the optical box, and the protruding portion is hooked by the hooking means. In addition, as the hooking means, for example, a wire or the like is used. As described above, since the locking means is locked to the holding member in a region partitioned from the scanning space of the light beam, the space above the optical component is not limited. Therefore, a three-dimensional optical layout can be formed without increasing the size of the entire apparatus.

According to a second aspect of the present invention, the hooking means comprises a wire hooked on a predetermined position of the holding member, and a tensioner for adjusting a tension applied to the wire. It is characterized in that the tension is increased by the tensioner when the hook is engaged, and the tension is reduced by the tensioner when the hook is released from the holding member by the wire.

According to the second aspect of the present invention, the hooking means comprises a wire and a tensioner. The wire is hooked on a hook formed on the holding member, and the tensioner adjusts the tension applied to the wire.
At this time, when the wire is hung on the holding member, the tension applied to the wire is increased by the tensioner. Thus, the optical components provided in the optical scanning device can be reliably fixed. On the other hand, when releasing the holding of the holding member by the wire, the tension applied to the wire is reduced by the tensioner. This allows
The optical scanning device can be easily disassembled. That is,
The optical scanning device can be disassembled simply by performing a simple operation of reducing the tension applied to the wire. In addition, since no screwing or the like is performed, all parts are not damaged during disassembly. For this reason, parts can be reused after cleaning / adjustment, replacement of consumable parts, etc., and a design excellent in recyclability can be achieved.

According to a third aspect of the present invention, the wire radiates heat generated by a driving unit for driving a deflector as the optical component.

In recent years, the speed of driving means for driving a deflector as an optical component tends to increase with an increase in speed and resolution from the market. The deflector continuously changes the incident angle of the light beam emitted from the light source and deflects it. When the number of rotations of the driving means for driving the deflector increases, heat is generated from the heat generating portion.
The life of the driving means is shortened. Therefore, according to the third aspect of the present invention, the wire radiates heat generated by the driving means for driving the deflector. That is, by disposing the wire near the heat generating portion of the driving means, heat generated from the driving means can be radiated through the wire. Therefore,
The life of the driving means can be extended.

According to a fourth aspect of the present invention, in the wire, a change in an optical path according to a temperature in the optical component held by the holding member is offset by a change in the posture of the optical component due to linear expansion of the wire itself. It is characterized by.

In an optical scanning device, optical components are sometimes arranged in, for example, an optical box. In this case, for example, a resin material is often used as the material of the optical box in consideration of cost reduction, but the optical box may be deformed when the temperature changes. For this reason, the attitude of the optical component arranged at a predetermined position of the optical box changes, and the light beam emitted from the light source fluctuates in the optical path, deteriorating the image quality of the image output from the image recording apparatus. Therefore, according to the fourth aspect of the present invention, the wire cancels the optical path fluctuation caused by the change in the attitude of the optical component held by the holding member by the change in the attitude of the optical component due to the linear expansion of the wire itself. For example, when the optical box is deformed when the temperature changes, the posture of the optical component changes and the optical path fluctuates. However, since the wire expands and contracts due to linear expansion, the posture of the optical component corrects the optical path fluctuation. Is changed to That is, the optical path fluctuation caused by the temperature change is corrected. Therefore, since the expansion and contraction due to the linear expansion of the wire is used, the optical path fluctuation according to the temperature can be corrected without using an expensive device.

According to a fifth aspect of the present invention, when the optical component is housed in an optical box of a housing, the wire is provided in contact with the optical box, and a drive for driving a deflector as the optical component is provided. The tension applied to the wire is adjusted by the tensioner so that the rotational frequency of the optical box and the natural frequency of the optical box do not resonate.

In recent years, the same optical scanning device can cope with image recording devices such as laser printers and digital copiers having different resolutions by changing the rotation speed of a deflector as an optical component. When the optical component is accommodated in the optical box of the housing, if the rotation speed of the driving unit is changed, the optical box resonates and the image quality deteriorates. Therefore, according to the fifth aspect of the present invention, the wire is provided in contact with the optical box of the optical scanning device, and the rotational frequency of the driving means for driving the deflector and the natural frequency of the optical box are different. Adjust the tension on the wire with a tensioner so that it does not resonate. As a result, an external force is applied to the optical box itself, and the natural frequency of the optical box can be changed with a simple configuration. Therefore, it is possible to prevent image quality deterioration caused by resonance of the optical box.

The invention according to claim 6 is characterized in that the adjustment of the tension by the tensioner is performed in conjunction with the resolution switching signal of the image recording apparatus.

For example, an image recording apparatus such as a laser printer or a digital copying machine may be controlled by a host computer. Therefore, according to the invention described in claim 6, when a signal (resolution switching signal) for changing the resolution is output from an external device such as a host computer, the tension applied to the wire is interlocked with the signal. Adjust with a tensioner. That is, the tension applied to the wire is adjusted so that the rotational frequency of the driving means for driving the deflector and the natural frequency of the optical box do not resonate. Thus, good image quality can always be provided.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION

[First Embodiment] As shown in FIG. 1, an image recording apparatus 12 incorporating an optical scanning device 10 according to the first embodiment includes a polygon mirror 14 (see FIG. 2) described later. Optical scanning device 10 and cylindrical photoreceptor 16
Is installed. A charger 18 is provided near the side surface of the photoconductor 16 along the rotation direction of the photoconductor 16 (the direction of arrow F). This charger 18 has a function of charging the surface of the photoconductor 16. A developing device 20 is disposed downstream of the installation position of the charging device 22 in the rotation direction of the photoconductor 16 so that toner adheres to the surface of the photoconductor 16. Further, a transfer charger 24 for transferring the toner from the surface of the photoconductor 16 to the sheet 22 is provided downstream of the photoconductor 16 in the rotation direction. Also, the photoconductor 16
The cleaner 26 that removes toner from the surface of the photoconductor 16 is disposed downstream of the transfer charger 24 in the rotation direction of the photoconductor 16. The paper 22 is transported in the direction of arrow G shown in FIG. 1, and the toner on the paper 22 is melted and fixed by a fixing device 28 installed on the downstream side in the transport direction of the paper 22.

FIG. 2 shows a schematic configuration of the optical scanning device 10 according to the first embodiment.

As shown in FIG. 2, the optical scanning device 10 includes an optical box 46 and a laser diode 30 as a light source. A collimator lens 32 for converting a light beam from the laser diode 30 from a diffused light beam to a parallel light beam is disposed near the emission side of the laser diode 30. Collimator lens 32
The light beam which has become a parallel light beam is focused on a reflection surface 14A provided on the side surface of the polygon mirror 14 having a regular polygonal prism shape through a cylinder lens 34 and a reflection mirror 36A.

The polygon mirror 14 is a regular polygonal prism (a regular hexagonal prism in FIG. 2) having a plurality of reflection surfaces 14A on its side surface, and the shaft 40 is driven by a driving force from a scanner motor 38 (see FIG. 5) described later. It rotates at high speed in the direction of arrow P at the center. As a result, the angle of incidence of the light beam on each reflecting surface 14A changes continuously and is deflected.

An fθ lens 42 is arranged in the traveling direction of the light beam deflected by the polygon mirror 14. The fθ lens 42 is for making the scanning speed when forming an image on the photoreceptor 16 uniform, and the first lens 4
2A and a second lens 42B. The light beam transmitted through the fθ lens 42 is bent by the reflection mirror 36B and the reflection mirror 36D, and is connected to a scanning surface of the photoconductor 16 (see FIG. 1) from a rectangular hole (not shown) provided on the bottom surface of the optical box 46. Imaged.

In the optical box 46, there is provided a photodetector 35 for detecting a write start timing of the optical scanning device 10.

Here, a method of fixing optical components such as the collimator lens 32, the cylinder lens 34, the polygon mirror 14, the fθ lens 42, and the reflection mirrors 36A, 36B, 36C and 36D to the optical box 46 of the optical scanning device 10 will be described. explain. In the first embodiment, a method for fixing the second lens 42B of the fθ lens 42 will be described in detail with reference to FIGS. 3 (A) and 3 (B).

As shown in FIGS. 3A and 3B,
An fθ lens 4 is provided on the bottom of the optical box 46 (only a part is shown).
Positioning members 48 and 49 are provided to indicate predetermined positions where the second second lenses 42B are arranged. Positioning member 48
Is formed integrally with a substantially L-shaped positioning main body 48A and a rectangular engaging piece 48B, and the positioning main body 48A is located above the bottom surface of the optical box 46 (inside the optical box 46),
It is attached so that the engagement piece 48B is located on the back surface of the optical box 46. At this time, the positioning member 48 is
The positioning member 48 can be attached by inserting the engagement piece 48B of the positioning member 48 into a slit hole formed on the bottom surface of the positioning member 48. Since the shapes of the positioning main body 48A and the engagement piece 48B are different, the positioning member 48 is locked at the boundary between the positioning main body 48A and the engagement piece 48B when inserted into the slit hole. The positioning member 49 is provided on the bottom surface of the optical box 46, and the hemispherical tip portion is f
The second lens 42B of the θ lens 42 is in contact with the second lens 42B.

The second lens 42B of the fθ lens 42
Is held by the holding member 50. The holding member 50 is
The cross-shaped flat plate is formed of a holding portion 50A having three sides bent at right angles and a leading end bent substantially in a U-shape, and an engagement piece 50B for attaching the holding member 50 to the optical box 46. , A so-called leaf spring. The holding portion 50A of the holding member 50 generates an elastic force by bending the distal end portion into a substantially U-shape with a radius of curvature corresponding to the shape of the fθ lens 42, and the elastic force of the holding member 50 secures the fθ lens 42. Can be held. That is, the fθ lens 42 is held by the holding portion 50A of the holding member 50 from above and on both sides in three directions, and is pressed and held. The holding member 50 is fitted in a rectangular hole formed in the optical box 46 with an engaging piece 50.
By inserting B, it can be attached.

Further, a hook 51 for hooking the wire 52 is formed on the engagement piece 50B of the holding member 50. The wires 52 are hooked on hooks 51 formed on the engagement pieces 50B of all the holding members 50 holding the optical components arranged in the optical box 46, and both ends are fixed members 54.
(See FIGS. 5A and 5B). A tensioner 55 (see FIG. 4) is provided on a part of the wire 52 so that the tension applied to the wire 52 can be adjusted.

FIGS. 4A and 4B show the structure of the tensioner 55. FIG. The tensioner 55 includes a square rod-shaped shaft 56 and a clip 5 bent in a substantially rectangular shape.
And 8. At one end of the shaft 56, a disk-shaped locking plate 56C is integrally formed.
Is formed at the other end thereof with a cutout portion 56B formed in a concave shape. The wire 52 passes through the cutout 56B. A plurality of grooves 56A (three in FIGS. 4A and 4B) for engaging the clips 58 are formed in the shaft 56. The width W1 of the groove 56A in the longitudinal direction of the shaft 56 is the same as the width W2 of the clip 58. Therefore, the tension applied to the wire 52 can be adjusted by selectively changing the groove 56A for engaging the clip 58.

As described above, when the wire 52 is hooked on the hook 51 formed on the engagement piece 50B of the holding member 50, the tension on the wire 52 is increased by the tensioner 55. Thereby, the optical component can be fixed at a predetermined position of the optical box 46. On the other hand, by reducing the tension of the wire 52 by the tensioner 55, the hooked state of the wire 52 can be easily released. That is, the optical components fixed to the optical box 46 can be removed, and the optical scanning device 10 can be easily disassembled.

Next, the operation of the first embodiment will be described. As shown in FIG. 1, the image recording device 12 is provided with an optical scanning device 10 and a photoconductor 16. Charger 18
The photoreceptor 16 charged by the above has a characteristic that when it is irradiated with a light beam, the potential of the light receiving portion is reduced. Therefore, the image recording device 12 has a structure utilizing this characteristic. That is, when the surface of the photoconductor 16 that is charged by the charger 18 and rotates in the direction of the arrow F is irradiated with light from the optical scanning device 10 indicated by the arrow J, the photoconductor 16
Of the light-receiving portion of the light-emitting device decreases. Thereby, the photoconductor 16
The toner is adhered by the developing device 20 to the light receiving portion on the surface of the substrate, that is, the portion where the potential is lowered. The toner attached to the photoconductor 16 is transferred to the photoconductor 16 by the transfer charger 24.
Is transferred to the sheet 22 from the surface of the sheet. Transferred paper 22
Is transported in the direction of arrow G, and the toner on the paper 22 is melted and fixed by the fixing device 28 provided on the downstream side in the transport direction. In this way, a desired image is output on the sheet 22.

Next, the optical scanning device 10 used in the image recording device 12 will be described. First, optical components (such as the collimator lens 32, the cylinder lens 34, the polygon mirror 14, and the fθ lens 42) are arranged at predetermined positions along a positioning member 48 provided in the optical box 46. After that, the engagement piece 50B of the holding member 50 is inserted into a slit hole formed on the bottom surface of the optical box 46. As a result, the optical component is nipped and held by the holding portion 50A of the holding member 50 from above and below the optical component in three directions. The holding member 5
The zero engagement piece 50B protrudes from the back surface of the optical box 46.

Subsequently, the wire 52 is hooked on the hook 51 provided on the engagement piece 50B of the holding member 50. At this time, all the holding members 50 that hold the optical components arranged in the optical box 46 are connected. Further, a tensioner 55 is provided on a part of the wire 52 so that the tension applied to the wire 52 can be adjusted. Hold the wire 52 to the holding member 5
When the wire 52 is hooked on the hook portion 51 formed at 0, the tension is adjusted by the tensioner 55 so that the tension applied to the wire 52 is increased. In this case, the holding member 50
Can be prevented from falling off, and the optical component can be reliably held.

On the other hand, the tension applied to the wire 52 is weakened by the tensioner 55 so that the holding member 50
The hooking state of the wire 52 by hooking on the hooking portion 51 can be easily released. Thereby, the optical component fixed to the optical box 46 can be removed,
The optical scanning device 10 can be easily disassembled.

As described above, only by weakening the tension applied to the wire 52 by the tensioner 55, the hooked state of the wire 52 is released, and the optical scanning device 10 can be easily disassembled. That is, since the optical parts are not screwed, the disassembling operation of the optical scanning device 10 becomes easy. Further, since the parts are not damaged when the optical scanning device 10 is disassembled, the parts can be reused after cleaning / adjustment, replacement of consumable parts, etc., and the design is excellent in recyclability. be able to. further,
Since the optical component is fixed on the back surface of the optical box 46, the space above the optical component is not limited. Therefore, a three-dimensional optical layout can be formed without increasing the size of the optical scanning device 10.

In the first embodiment, all of the holding members 50 for holding a plurality of optical components are connected by one wire 52, and one tensioner 55 adjusts the tension applied to the wire 52. Scanning device 10
(Refer to FIGS. 5A and 5B). However, when it is difficult to connect with one wire 52 due to the arrangement of the optical components, a plurality of wires and tensioners may be used.

As shown in FIGS. 6A and 6B, the wire 52 may be brought into contact with a radiator plate 62 provided near the drive IC of the scanner motor 38 for instructing the rotation of the polygon mirror 14. Good. This allows the entire wire 52 to be used as a heat dissipating member,
The release of heat generated from the driving IC can be promoted. As a result, the life of the scanner motor 38 is extended. At this time, it is desirable to use a material having a high thermal conductivity such as iron as a material of the wire 52. In addition, if the heat radiating plate is enlarged and the wire 52 is brought into contact with the cooling fan or the wire 52 passes near the cooling fan, the heat radiation can be more effectively promoted.

Further, in the first embodiment, the scanner motor 38 is fixed with screws 61 as shown in FIG. This is to suppress vibration due to rotation of the scanner motor 38. However, optical box 4
Since the plate 60 is disposed on the back surface of the optical box 6 and screwed to the plate 60, the optical box 46 is not damaged.

[Second Embodiment] A resin material is often used for the optical box 80 of the optical scanning device 10A for cost reduction, as shown in FIGS. 7A and 7B. When the temperature changes, the optical box 80 may be deformed, and the posture of the optical component may change. For example, a reflection mirror 64 as an optical component
Is disposed, the optical path of the light beam emitted from the laser diode 30 is changed in the Z direction (upward in FIG. 7) by tilting the reflection mirror 64. As a result, the shape of the beam spot irradiated on the photoreceptor 16 is distorted, the writing position is shifted, the reproducibility of characters and fine lines is deteriorated, and in the case of a color machine, color shift occurs. Image quality degradation occurs.

FIG. 8 shows the optical box 46 of the optical scanning device 10A.
Some of the components within are shown. As shown in FIG. 8, the reflection mirror 64 as an optical component is positioned and arranged by two protrusions 66A and 66B provided on the optical box 80 and a protrusion 70 provided on the positioning member 68. . The positioning member 68 is bent at two obtuse angles in the longitudinal direction (the left-right direction in FIG. 8). One end of the wire 52 is connected to one end of the positioning member 68, and a pair of hemispherical recesses 68 </ b> A are formed on a surface parallel to the bottom surface of the optical box 80 as the other side. The recess 68 on the near side is shown in FIG.
A only is shown). Correspondingly, a pair of projections 74 (only one is shown in FIG. 8) are provided inside the bottom surface of the optical box 80, and the tips of the projections 74 are accommodated in recesses 68 </ b> A formed in the positioning member 68. ing. Also, the optical box 80
An O-ring 78 is mounted between the bottom surface of the first member and the positioning member 68. The O-ring 78 is an elastically deformable member such as rubber, and plays a role of elastically supporting the positioning member 68 and absorbing external vibration and the like. Thus, the positioning member 68 is rotatable in the direction of arrow A shown in FIG. 8 around the tip of the projection 74 by the pair of projections 74 provided on the optical box 80.

The holding member 72 is composed of two divided members (72A, 72B). That is,
A holding member 72A for holding the reflection mirror 64 from the back side of the reflection mirror 64 and a holding member 72B for holding the other end of the positioning member 68 (the side opposite to the side on which one end of the wire 52 is connected and fixed). Both have a function as a leaf spring.

One of the holding members 72A is erected and penetrates a slit hole 73 provided on the bottom surface of the optical box 80, and the other upper end is bent in a substantially U-shape. In addition, a part of the substantially U-shaped bent portion has a contact protrusion 7.
1 is provided. The contact projection 71 contacts and holds the reflection mirror 64. One holding member 72B is erected similarly to the holding member 72A, penetrates a slit hole 73 provided on the bottom surface of the optical box 80, and the other upper end portion is formed in a substantially S shape. ing. Part of the substantially S-shaped bent portion contacts the positioning member 68,
This positioning member 68 is held.

The wire 52 connected and fixed to one of the positioning members 68 is routed to the back side of the optical box 80, and holds the holding member 72A holding the reflection mirror 64 and the holding member 72 holding the positioning member 68. 72B. That is, the wire 52 is hooked on a hook (not shown in FIG. 8 but has the same shape as the hook 51 shown in FIG. 3A) formed on the holding members 72A and 72B as described above. Has been stopped. The tension applied to the wire 52 is adjusted by a tensioner 76. By adjusting the tension applied to the wire 52,
The position of the reflection mirror 64 can be initialized.

Thereafter, the temperature of the optical box 8 is changed by a change in temperature.
When 0 is deformed, the attitude of the reflection mirror 64 changes, causing an optical path fluctuation. However, in this case, the wire 52
Expands and contracts due to the linear expansion, and the attitude of the reflection mirror 64 is changed in a direction to correct the optical path fluctuation. Therefore, even when the optical path changes due to the temperature change, the wire 5
The optical path fluctuation according to the temperature can be corrected by expansion and contraction due to the linear expansion of 2.

FIG. 9 shows an optical path variation characteristic 84 obtained by measuring the optical path variation due to the temperature change. This optical path variation characteristic 84 is detected by a sensor 82 arranged at a position at a distance M (210 mm) from the reflection mirror 64.

As shown in FIG. 9, the optical path variation characteristic 84
Is substantially proportional to a change in temperature. That is, the variation is about 0.03 mm / ° C., for example, 1
When the temperature of 0 ° C. changes, the amount of change is 0.3 mm.
At this time, for example, the attachment span of the reflection mirror 64 is 10 m.
m, the protrusion 7 provided on the positioning member 68
The variation d at 0 is obtained by the following equation (1).

(D / 10) = (0.3 / 210) d = (0.3 / 210) × 10 (1) Accordingly, the variation d in the projection 70 provided on the positioning member 68 is From equation (1), it can be determined to be 0.014 mm.

The wire 52 is often made of iron. The linear expansion coefficient of iron is 11.7 × 10 ⁻⁶ mm · mm / ° C.
Therefore, for example, the wire 52 required to correct the fluctuation amount of the optical path of 0.3 mm when the temperature changes by 10 ° C.
The length L can be determined by the following equation (2) using the variation d of the protrusion 70 obtained by the equation (1).

L = 0.014 / (11.7 × 10 ⁻⁶ ) / 10 (2) That is, the length L of the wire 52 is determined to be 119.7 mm. Thus, the optimal length L of the wire 52
By selecting, it is possible to correct the optical path fluctuation according to the temperature.

[Third Embodiment] In recent years, the same optical scanning device 10B may be used for image recording devices 12 having different printing speeds and resolutions. At this time, the optical scanning device 10
By changing the number of revolutions of the scanner motor 38 provided for B, each of the image recording devices 12 is made to correspond to each other. However, when the rotation speed of the scanner motor 38 changes, the optical box 84 resonates, and the image quality deteriorates.

Therefore, as shown in FIG. 10, in the optical scanning device 10B, the wire 52 connecting the holding member holding the optical components is brought into contact with the optical box 84.

As shown in FIG. 10, the wire 52 is passed through three round holes formed in the optical box 84 and both ends are fixed by tensioners 86 (FIG. 10).
(In (A), only one end of the wire 52 is shown.) The tension applied to the wire 52 is adjusted by a tensioner 86, so that the natural frequency of the optical box 84 can be changed. That is, since an external force can be applied to the optical box 46 itself through the wire 52,
The natural frequency of the optical box 84, that is, the resonance frequency can be changed with a simple configuration.

Accordingly, the tension applied to the wire 52 is adjusted by the tensioner 86 so that the natural frequency of the optical box 84 does not resonate with the rotation frequency of the scanner motor 38 for driving the polygon mirror 14 when the scanner is driven. Can be prevented from deteriorating the image quality caused by the resonance.

In some cases, the image recording apparatus 12 is controlled by a host computer, and a resolution switching signal instructing to switch the resolution is output from the host computer. In such a case, the tension applied to the wire 52 may be adjusted in conjunction with the output of the resolution switching signal.

In the present embodiment, the optical scanning device 10,
Although the example in which the optical components are arranged in the optical boxes 46, 80, and 84 provided in 10A and 10B has been described, the members for disposing the optical components are optical boxes (that is, box-shaped members).
However, the present invention is not limited to this. For example, you may make it arrange | position to a plate-shaped member.

In the present embodiment, a leaf spring formed so that an elastic force is generated by bending a part of a cross-shaped flat plate into a substantially U-shape is used as a holding member. It is not something to be done. For example, a coil spring or the like may be used as the holding member.

[0059]

As described above, according to the present invention, the locking means is locked to the holding member in a region separated from the scanning space of the light beam, so that the three-dimensional structure can be realized without increasing the size of the entire apparatus. This has an excellent effect that an optical layout can be formed.

Also, the optical scanning device can be easily disassembled only by weakening the tension applied to the wire, and the disassembly does not damage parts.
There is an excellent effect that parts can be reused after cleaning / adjustment, replacement of consumable parts, and the like.

Further, since the heat generated from the driving means for driving the deflector is released through the wire, the life of the driving means for driving the deflector can be extended, so that there is an excellent effect.

Further, since the expansion and contraction due to the linear expansion of the wire is used, there is an excellent effect that the optical path fluctuation depending on the temperature can be corrected without using an expensive device.

Further, the tension applied to the wire can be adjusted so that the natural frequency of the optical box and the rotational frequency of the driving means for driving the deflector do not resonate. Also has an excellent effect that image quality deterioration due to resonance can be prevented.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing a configuration of an image recording device incorporating a light scanning device of the present invention.

FIG. 2 is a schematic configuration diagram showing an internal structure of an optical box of the optical scanning device according to the first embodiment of the present invention.

FIG. 3 is a schematic configuration diagram illustrating details of an optical component holding unit of the optical scanning device according to the first embodiment of the present invention. (A)
3A is a perspective view of the optical component holding unit, and FIG. 3B is a side view of FIG.

FIG. 4 is a schematic configuration diagram illustrating a configuration of a tensioner member that applies tension to a fixing member. (A) is an exploded perspective view of the tensioner, and (B) is a perspective view showing a state where the tensioner is attached to the optical scanning device.

FIG. 5 is a schematic view showing a state where an optical component is fixed.
(A) is a front view showing the inside of the optical box, and (B) is a rear view showing the back of the optical box.

FIG. 6 is a schematic diagram showing the vicinity of a deflector (polygon mirror) arranged as an optical component. (A) is a front view showing the inside of the optical box and the vicinity of the polygon mirror,
(B) is a rear view showing the vicinity of a scanner motor for instructing rotation of the polygon mirror.

FIG. 7 is a schematic diagram showing deformation of the optical box of the optical scanning device when the temperature changes. (A) shows a perspective view at the time of deformation, and (B) shows a side view.

FIG. 8 is a side view showing an optical component (reflection mirror) mounting structure in an optical scanning device according to a second embodiment of the present invention.

FIG. 9 is a characteristic diagram showing an optical path variation characteristic due to a temperature change.

FIG. 10 is a configuration diagram illustrating an optical scanning device according to a third embodiment of the present invention. FIG. 2A is a schematic configuration diagram illustrating an optical scanning device in which an optical box is fixed by an optical box fixing member;
(B) is a graph showing the tension applied to the optical box fixing member and the optical box transfer function.

FIG. 11 is a schematic view showing a method of fixing an optical component in a conventional optical scanning device. (A) is a schematic perspective view when snap-fitting is fixed to an optical box using an elastic member capable of snap-fitting, and (B) is a perspective view when an optical component is bonded to the optical box. . (C) is a sectional view taken along line CC in (B).

FIG. 12 is a configuration diagram showing a conventional optical scanning device.
(A) is an exploded perspective view of the optical scanning device, and (B)
FIG. 3 is a sectional view taken along line BB of FIG.

[Explanation of symbols]

 10, 10A, 10B Optical scanning device 12 Image recording device 14 Polygon mirror (optical component, deflector) 16 Photoconductor 30 Laser diode 32 Collimator lens (optical component) 34 Cylinder lens (optical component) 38 Scanner motor (drive unit) 42 fθ lens (optical part) 46 optical box 50, 72 holding member (holding member) 52, 53 wire (hook means) 54, 86 tensioner (hook means) 64 reflection mirror (optical part)

Claims (6)

[Claims] 1. An optical component for converging a light beam emitted from a light source to form an image on a surface to be scanned, and a detachable holding member for holding the optical component arranged in the vicinity of a predetermined position by elastic force. An optical scanning device, comprising: a locking unit that is locked to the holding member in a region partitioned from the light beam scanning space and prevents the holding member from falling off. 2. The hooking means comprises a wire hooked on a predetermined position of the holding member, and a tensioner for adjusting a tension applied to the wire. When the wire is hooked on the holding member, the tensioner uses a tensioner. 2. The optical scanning device according to claim 1, wherein the tension is reduced by a tensioner when the holding member is released from the hook by the wire. 3. The optical scanning device according to claim 2, wherein the wire radiates heat generated by a driving unit that drives a deflector as the optical component. 4. The wire according to claim 2, wherein a change in the optical path of the optical component held by the holding member in accordance with the temperature is offset by a change in the attitude of the optical component due to linear expansion of the wire itself. The optical scanning device according to claim 1. 5. When the optical component is accommodated in an optical box of a housing, the wire is provided in contact with the optical box, and a driving unit for driving a deflector as an optical component is driven. The optical scanning device according to any one of claims 2 to 4, wherein the tension applied to the wire is adjusted by the tensioner so that a rotation frequency and a natural frequency of the optical box do not resonate. 6. The optical scanning device according to claim 5, wherein the adjustment of the tension of the wire by the tensioner is performed in conjunction with a resolution switching signal of an image recording device.