JP7394590B2 - Optical scanning device and image forming device equipped with the same - Google Patents

Description

The present invention relates to an optical scanning device and an image forming apparatus such as a copying machine, a multifunction device, a printer, and a facsimile machine.

An optical scanning device is generally a device that deflects and scans a light beam emitted from a light source (eg, a laser diode element) in a predetermined main scanning direction using a deflector (eg, a rotating polygon mirror).

The deflector is generally housed in a hollow housing for sound and dust proofing, and is built into the casing of the optical scanning device, and vibrates together with the housing as it rotates at high speed. Further, the casing of the optical scanning device generally includes a top cover for sound and dustproofing, and vibrates due to vibrations transmitted from the image forming device. If no precautions are taken against the vibrations of the deflector or the housing, the deflected and scanned light beam will shift, resulting in blurred print produced by the image forming apparatus. Therefore, as a measure to alleviate the vibration of the deflector or the housing, an elastic member is used (see, for example, Patent Document 1 and Patent Document 2).

Japanese Patent Application Publication No. 5-164983 Japanese Patent Application Publication No. 2013-44858

Patent Document 1 discloses a structure in which transmission of vibrations of the deflector to the optical scanning device is insulated by an elastic member provided between the motor and the housing of the deflector. Further, in Patent Document 2, an optical scanning device is fastened to an image forming device via an elastic member, so that the elastic member is held in pressure contact between the optical scanning device and the image forming device, and, A structure is disclosed in which vibration of the optical scanning device is suppressed by the elastic member.

The means disclosed in Patent Document 1 is only a means for reducing the vibration of the optical scanning device by making it difficult for the vibration of the deflector to be transmitted to the optical scanning device, and therefore is insufficient to suppress the vibration of the deflector. Further, there is a problem in that vibrations transmitted from the image forming device to the housing of the optical scanning device are not suppressed at all.

Therefore, as a vibration damping means for suppressing both the vibration of the deflector and the vibration of the casing of the optical scanning device, a vibration damping means that suppresses both the vibration of the deflector and the vibration of the casing of the optical scanning device is proposed, following Patent Document 2, between the housing in which the deflector is built and the casing of the optical scanning device. It is conceivable to press and hold the elastic member between the two. Specifically, by pressing and sandwiching an elastic member between the top cover of the case of the optical scanning device and the cover material of the housing of the deflector, the vibration of the case of the optical scanning device and the cover of the deflector housing are suppressed. It is conceivable to suppress vibrations and, by extension, vibrations of the deflector. However, following Patent Document 2, the elastic member is provided at the end of the lid of the deflector housing. However, since the deflector housing is hollow, the amplitude at the center of the lid is larger than the amplitude at the ends of the lid. Therefore, the elastic member provided at the end of the deflector housing, as disclosed in Patent Document 2, has a problem in that it is inefficient in suppressing vibrations of the deflector housing and ultimately vibrations of the deflector.

The present invention has been made to solve all of the above problems, and is capable of simultaneously and efficiently damping the vibrations of the casing of the optical scanning device, the vibrations of the deflector housing, and the vibrations of the deflector. As a result, it is an object of the present invention to provide an optical scanning device that can reduce printing blur caused by these vibrations, and an image forming apparatus equipped with the same.

In order to achieve the above object, an optical scanning device of the present invention includes a deflector that deflects and scans light, a covered hollow housing, and a covered hollow deflector housing inscribed in the housing and housing the deflector. and an elastic member held in pressure contact between the lid of the deflector accommodating part and the lid of the casing, and in a plan view of the deflector accommodating part, the elastic member It is a part of the top surface of the lid section, is provided at the center of the top surface of the lid section, and is positioned by a projection provided on the top surface of the lid section of the deflector accommodating section. Features.

Further, the lid portion of the casing may be made of metal.

Further, the elastic member may have a through hole passing through between the lid of the deflector accommodating portion and the lid of the casing.

Further, the elastic member may be formed by laminating a plurality of elastic layers.

Further, the elastic member is formed by laminating a plurality of elastic layers, and the elastic layer includes a first elastic layer that is in contact with the lid of the deflector accommodating section, and a first elastic layer that is in contact with the lid of the casing. a second elastic layer, the hardness of the first elastic layer may be higher than the hardness of the second elastic layer.

Further, an image forming apparatus according to the present invention is characterized in that it includes the optical scanning device.

According to the present invention, since the elastic member held in pressure contact between the lid of the casing and the lid of the deflector accommodating part is configured to suppress the casing and the deflector accommodating part together, Vibrations of the casing, vibrations of the deflector accommodating portion, and ultimately vibrations of the deflector are suppressed comprehensively. In addition, since the elastic member is provided in the central portion of the deflector accommodating portion in a plan view where the amplitude is large, vibrations of the deflector accommodating portion and, in turn, vibrations of the deflector are efficiently suppressed.

1 is a schematic vertical cross-sectional view showing the front of an image forming apparatus according to Embodiment 1 of the present invention. 1 is a schematic cross-sectional plan view of an optical scanning device according to Embodiment 1 of the present invention. 3 is a perspective view of the optical scanning device of FIG. 2. FIG. 3 is a plan view of the optical scanning device of FIG. 2. FIG. 3 is a bottom view of the optical scanning device of FIG. 2. FIG. FIG. 3 is an exploded perspective view of the optical scanning device of FIG. 2 with a lower cover removed. FIG. 2 is a perspective view showing a deflector accommodating portion according to Embodiment 1 of the present invention. 5 is a cross-sectional view taken along the line AA in FIG. 4. FIG. It is a perspective view which shows the deflector accommodating part based on Embodiment 2 of this invention. FIG. 7 is a sectional view showing a longitudinal section of an elastic member according to Embodiment 3 of the present invention.

Embodiments of the present invention will be described below with reference to the accompanying drawings. In the following description, the same parts and the like are given the same reference numerals, and the names and functions of these parts and the like are also the same. Therefore, detailed explanations of those parts and the like are omitted.

(Embodiment 1)
-Overall configuration of image forming device-
FIG. 1 is a schematic cross-sectional view of an image forming apparatus 100 according to the present embodiment viewed from the front. In the figure, symbol X represents the depth direction, symbol Y represents the left-right direction, and symbol Z represents the up-down direction (vertical direction). The symbol X1 represents the main scanning direction of the light beam.

Image forming apparatus 100 according to this embodiment is a monochrome image forming apparatus. The image forming apparatus 100 performs image forming processing according to image data read by the image reading apparatus 1 or image data transmitted from the outside. Note that the image forming apparatus 100 may be a color image forming apparatus that forms multicolor and monochrome images on the paper P.

Image forming apparatus 100 includes a document feeder 108 and an image forming apparatus main body 110. The image forming apparatus main body 110 is provided with an image forming section 102 and a paper transport system 103.

The image forming section 102 includes an optical scanning device 200 (optical scanning unit), a developing unit 2, a photosensitive drum 3 that acts as an electrostatic latent image carrier, a cleaning section 4, a charging device 5, and a fixing unit 7. Further, the paper transport system 103 includes a paper feed tray 81 , a manual paper feed tray 82 , an ejection roller 31 , and an ejection tray 14 .

An image reading device 1 for reading an image of a document G is provided at the top of the image forming apparatus main body 110. The image reading device 1 includes a document placement table 107 on which a document G is placed. Further, a document feeder 108 is provided above the document table 107. In the image forming apparatus 100, the image of the document G read by the image reading apparatus 1 is sent as image data to the image forming apparatus main body 110, and the image is recorded on the paper P.

The image forming apparatus main body 110 is provided with a paper conveyance path S1. The paper feed tray 81 or the manual paper feed tray 82 supplies paper P to the paper transport path S1. The paper transport path S1 guides the paper P to the discharge tray 14 via the transfer roller 10 and the fixing unit 7. The fixing unit 7 heats and fixes the toner image formed on the paper P to the paper P. Pick-up rollers 11a and 11b, a conveyance roller 12a, a registration roller 13, a transfer roller 10, a heat roller 71 and a pressure roller 72 in the fixing unit 7, and a discharge roller 31 are arranged near the paper conveyance path S1.

In the image forming apparatus 100 , the paper P supplied from the paper feed tray 81 or the manual paper feed tray 82 is conveyed to the registration rollers 13 . Next, the paper P is conveyed to the transfer roller 10 by the registration roller 13 at a timing to align the paper P and the toner image on the photoreceptor drum 3 . The toner image on the photosensitive drum 3 is transferred onto the paper P by a transfer roller 10. Thereafter, the paper P passes through a heat roller 71 and a pressure roller 72 in the fixing unit 7, passes through a conveyance roller 12a and an ejection roller 31, and is ejected onto an ejection tray 14. When forming an image not only on the front side but also on the back side of the paper P, the paper P is conveyed in the opposite direction from the discharge roller 31 to the reversing paper conveyance path S2. The paper P passes through the reversing conveyance rollers 12b to 12b, reverses the front and back of the paper P, and is led to the registration rollers 13 again. Then, the paper P is discharged toward the discharge tray 14 after a toner image is formed and fixed on the back surface in the same manner as on the front surface.

-Optical scanning device-
FIG. 2 is a schematic cross-sectional plan view of the optical scanning device 200 in the image forming apparatus 100 shown in FIG. 3 is a perspective view of the optical scanning device 200, FIG. 4 is a plan view of the optical scanning device 200, and FIG. 5 is a bottom view of the optical scanning device 200. FIG. 6 is an exploded perspective view showing the optical scanning device 200 with the lower cover 204 removed. Note that in FIG. 4, illustration of the upper lid 202 is omitted.

FIG. 7 is a perspective view showing the deflector accommodating part 203 of the present invention, and FIG. 8 is a sectional view showing the AA cross section of the deflector accommodating part 203. Note that in FIG. 7, illustration of the upper lid 202 is omitted.

The optical scanning device 200 includes a housing 201, an input optical system 210, a deflector 220 (deflection scanning section), and an output optical system 230.

<Incidence optical system>
The input optical system 210 includes a light source 211 (laser diode element), a collimator lens 212, an aperture member 213, a cylindrical lens 214, and a light source reflection mirror 215. The light source 211 emits a light beam L (laser beam). The collimator lens 212 converts the light beam L from the light source 211 into substantially parallel light and irradiates it onto the aperture member 213 . The aperture member 213 focuses the light beam L from the collimator lens 212 and irradiates it onto the cylindrical lens 214 . The cylindrical lens 214 converges the light beam L from the aperture member 213 only in the sub-scanning direction and focuses it on the reflective surface 223a of the deflection scanning member 223 (polygon mirror) via the light source reflective mirror 215. The light source reflection mirror 215 guides the light beam L from the cylindrical lens 214 to the reflection surface 223a of the deflection scanning member 223 (polygon mirror).

The optical scanning device 200 further includes a substrate 240 (a substrate for a light source and a beam detection section). A light source 211 is provided on the substrate 240. The substrate 240 is a flat printed circuit board and includes a circuit for driving the light source 211. This board 240 is attached to the side plate 201d of the housing 201, and is connected to a control board 290, which will be described later, via a flat cable FC (see FIG. 7).

<Deflector>
The deflector 220 includes a deflection scanning substrate 221, a deflection scanning motor 222 (polygon motor), and a deflection scanning member 223 (rotating polygon mirror) (see FIGS. 2 and 6). A deflection scanning motor 222 is provided on the deflection scanning substrate 221 . A deflection scanning member 223 that deflects and scans the light beam L from the light source reflection mirror 215 in a predetermined main scanning direction X1 is fixed to the rotation shaft 222a. The deflection scanning board 221 is fixed to the plane (upper surface) side of the lower lid 204 with a plurality of fixing members (screws) SC1 to SC1 (see FIGS. 6 and 8). When the deflection scanning board 221 is fixed to the lower lid 204, the lower end of the rotating shaft 222a of the deflection scanning motor 222 passes through the lower lid 204 and emerges from the bottom surface (lower surface) of the lower lid 204.

The deflection scanning board 221 is a flat printed circuit board, and has a circuit for driving the deflection scanning motor 222. A deflection scanning motor 222 is fixed on the deflection scanning substrate 221, and a center portion of a deflection scanning member 223 is connected and fixed to a rotating shaft 222a of the deflection scanning motor 222. The deflection scanning member 223 is rotationally driven by the deflection scanning motor 222.

<Output optical system>
The output optical system 230 includes an fθ lens 231, a beam detection reflection mirror 232, a beam detection lens 233 (condensing lens), and a beam detection section 234 [Beam Detect sensor (BD sensor)] (FIG. 2). reference).

The fθ lens 231 has an elongated shape in the main scanning direction X1. The fθ lens 231 receives the light beam L deflected and scanned by the deflection scanning member 223 in the main scanning direction X1 (longitudinal direction W). The beam detection reflection mirror 232 guides the light beam L deflected and scanned by the reflection surface 223a of the deflection scanning member 223 to the beam detection lens 233. The beam detection unit 234 detects the main scanning start timing (image writing start timing) of the light beam L.

<Housing>
The housing 201 is made of, for example, a flame-retardant synthetic resin material, and has a rectangular bottom plate 201a and four side plates 201b to 201e surrounding the bottom plate 201a (see FIGS. 3 to 6). The housing 201 is provided with a deflector accommodating portion 203 (see FIGS. 2 and 4) that covers the deflector 220. The deflector accommodating section 203 is formed into a hollow box shape by a accommodating section top surface 205, accommodating section side surfaces 206a to 206d extending along the outer periphery of the accommodating section top surface 205, and a lower lid 204. (See Figure 7). This storage section top surface 205 corresponds to the "cover section of the deflector storage section" in the claims of the present application. The housing section top surface 205 and the housing section side surfaces 206a to 206d are integrally molded with the housing 201, and the housing section side surfaces 206a to 206d form an opening 203a below the deflector housing section 203 (Fig. 6 reference). The opening 203a is closed by a lower lid 204, and the lower lid 204 is fixed to the bottom surface (lower surface) side of the bottom plate 201a with a plurality of fixing members (screws) SC2 to SC2 (see FIGS. 6 and 8). ). A deflector 220 is disposed on the lower lid 204, and by fixing the lower lid 204 to the bottom plate 201a, the inside of the deflector accommodating portion 203 is formed in which the deflector 220 is accommodated. A control board 290 is fixed to the bottom surface (lower surface) of the bottom plate 201a with a plurality of fixing members (screws) SC3 to SC3. The control board 290 is a flat printed circuit board and includes a circuit for controlling the optical scanning device 200.

The deflector 220 and the lower lid 204 on which the deflector 220 is disposed vibrate as the deflection scanning motor 222 rotates. Vibrations generated as the deflector 220 rotates are transmitted to the housing side surfaces 206a to 206d and the housing top surface 205 via fixing members (screws) SC2 to SC2 of the lower lid 204. In other words, the housing section top surface 205 is configured to vibrate indirectly as the deflector 220 rotates. Since the deflector accommodating part 203 is hollow, the center part of the accommodating part top surface 205 is a more open part compared to the end part of the accommodating part top surface 205. The amplitude at the center of the housing section top surface 205 is larger than the amplitude at the end portions of the housing section top surface 205.

Furthermore, the housing 201 is provided with an upper lid 202 that closes the upper opening of the housing 201 (see FIG. 3). This upper lid 202 corresponds to the “lid portion of the housing” in the claims of the present application. The upper lid 202 is made of a sheet metal such as SECC, for example. Since the upper lid 202 is made of metal, the upper lid 202 helps efficiently radiate heat from a deflector 220 (described later) to the outside of the optical scanning device 200.

The optical scanning device 200 is installed inside the image forming apparatus 100 (see FIG. 1). Therefore, the vibration of the image forming apparatus 100 is transmitted to the casing 201 of the optical scanning device 200 attached to the image forming apparatus 100, and then to the top lid 202 provided on the casing 201. In other words, the upper lid 202 has a structure that vibrates as the image forming apparatus 100 vibrates.

<Elastic member>
An elastic member 500 is sandwiched between the housing section top surface 205 and the upper lid 202 (see FIG. 8). Since the thickness of the elastic member 500 is set to be larger than the gap between the top surface 205 of the storage section 205 and the top lid 202, the elastic member 500 is compressed between the top surface 205 of the storage section 205 and the top lid 202. It has a sandwiched structure. Since the elastic member 500 is pressed and held between the top surface 205 of the storage section 205 and the top lid 202, the elastic member 500 is reliably contacted with the top surface 205 of the storage section 205 and the top lid 202, and the elastic member 500 is The structure is such that a load due to the repulsive force is applied to each of the top surface 205 of the housing section and the top lid 202.

In addition, the elastic member 500 is provided at the center of the top surface 205 of the storage section 205 in a plan view (that is, when viewed from the Z direction) (see FIG. 4). It is positioned by the letter-shaped protrusion 205a.

The elastic member 500 is provided for the purpose of suppressing the vibrations of the deflector 220 and the casing 201, that is, damping them.

The vibrations of the deflector 220 are damped by the elastic member 500 as follows. In other words, since the central portion of the top surface 205 of the housing section 205 has a large amplitude and is in contact with the elastic member 500, the vibration energy generated as the deflector 220 rotates is transferred from the lower lid 204 to the deflector housing section 203. This is transmitted and, in turn, absorbed into the elastic member 500 as an internal loss via the top surface 205 of the housing section. In addition, since the center portion of the top surface 205 of the storage portion where the amplitude is large is suppressed by the repulsive force of the elastic member 500, the vibration of the top surface 205 of the storage portion is efficiently suppressed. As the vibration of the housing top surface 205 forming the deflector housing 203 is suppressed, the vibration of the lower lid 204 that is integrated with the deflector housing 203 is suppressed, and as a result, the vibration of the deflector 220 is suppressed. suppressed.

Similarly, the vibration of the housing 201 is damped by the elastic member 500 as follows. That is, because the upper lid 202 is in contact with the elastic member 500, the vibration energy of the housing 201 is absorbed as internal loss into the elastic member 500 via the upper lid 202. Since the upper lid 202 is suppressed by the repulsive force of the elastic member 500, vibration of the upper lid 202 is suppressed. As the vibration of the upper lid 202 is suppressed, the vibration of the housing 201 that is integrated with the upper lid 202 is suppressed.

In the above-described structure in which the elastic member 500 is held in pressure contact between the top surface 205 of the accommodating portion and the upper lid 202, and the elastic member 500 is provided at the center of the top surface 205 of the accommodating portion, The vibrations generated by the rotation of the deflector 220 and the vibrations of the housing 201 are absorbed by the elastic member 500, and as these vibrations are efficiently suppressed, the vibrations of the deflector 220 and the vibrations of the top cover 202 are absorbed. This results in the effect that the vibrations are comprehensively suppressed.

The elastic member 500 is made of, for example, a rubber material such as chloroprene rubber, and its rubber hardness includes a low hardness of about 25±5. Rubber hardness is determined according to JIS K6253. A loss coefficient is generally used as an evaluation index for vibration damping materials, and it is said that the larger the loss coefficient, the greater the damping effect. The loss coefficient η is determined by η=(loss modulus)/(storage modulus). Rubber materials with low hardness tend to have a small storage modulus and a large loss coefficient η, and are therefore widely used as vibration damping materials. Note that the elastic member 500 may be formed from a single layer of rubber material, or may be formed from a stack of multiple layers of rubber material. Furthermore, an adhesive layer may be provided on the elastic member 500 in order to bring the elastic member 500 into stable contact with the top surface 205 of the housing section 205 or the top lid 202.

Incidentally, the deflector 220 rotates at a high speed and generates heat, and the heat causes a temperature rise inside the deflector housing section 203, and scanning deviation may occur due to the temperature rise. Therefore, a structure is required that appropriately dissipates the heat inside the deflector accommodating section 203. However, as described above, since the elastic member 500 is provided on the surface of the accommodating part top surface 205 of the deflector accommodating part 203, at least the contact area where the elastic member 500 is in contact with the accommodating part top surface 205 is The heat dissipation area of the housing section top surface 205 decreases accordingly. In other words, the elastic member 500 provided on the surface of the top surface 205 of the accommodating portion may impede heat radiation of the deflector 220.

Therefore, a cylindrical through hole 505A is provided in the center of the elastic member 500, passing through between the storage section top surface 205 and the upper lid 202 (see FIGS. 7 and 8). The through hole 505A penetrates through the elastic member 500 in the thickness direction, and has a diameter of, for example, about 3 mm. The through hole 505A provides a heat radiation path for radiating the heat transferred from the deflector 220 to the top surface 205 of the accommodating portion to the top lid 202. Thereby, the heat of the deflector 220 can be appropriately radiated to the outside of the optical scanning device 200 via the upper lid 202. Note that the shape of the through hole 505A is not limited to a cylindrical shape, but may be a rectangular tube shape or a conical shape.

Next, the optical path of the light beam L from the light source 211 until it enters the photoreceptor drum 3 will be explained.

The light beam L from the light source 211 passes through a collimator lens 212 to become approximately parallel light, is focused by an aperture member 213, passes through a cylindrical lens 214, enters a light source reflection mirror 215, is reflected, and is deflected. The light is incident on the reflective surface 223a of the scanning member 223. The deflection scanning member 223 is rotated in a predetermined rotation direction R at a constant angular velocity by the deflection scanning motor 222, and successively reflects the light beam L on each reflecting surface 223a, and repeatedly reflects the light beam L in the main scanning direction X1 at a constant angular velocity. deflect. The fθ lens 231 focuses the light beam L to a predetermined beam diameter on the surface of the photoreceptor drum 3 in both the main scanning direction X1 and the sub-scanning direction. Further, the fθ lens 231 converts the light beam L, which is deflected at a constant angular velocity in the main scanning direction X1 by the deflection scanning member 223, so that it moves at a constant angular velocity on the photoreceptor drum 3. Thereby, the light beam L can repeatedly scan the surface of the photoreceptor drum 3 in the main scanning direction X1.

Further, the beam detection unit 234 receives the light beam L reflected by the beam detection reflection mirror 232 immediately before main scanning (writing) of the photoreceptor drum 3 is started. The beam detection unit 234 receives the light beam L at a timing immediately before the main scanning of the surface of the photoreceptor drum 3 is started, and outputs a BD signal indicating the timing immediately before the main scanning starts. The start timing of main scanning of the photosensitive drum 3 on which a toner image is formed is set in accordance with this BD signal, and writing with the light beam L is started in accordance with image data. The two-dimensional surface (circumferential surface) of the photoreceptor drum 3, which is rotated and charged, is scanned by the light beam L, and each electrostatic latent image is formed on the surface of the photoreceptor drum 3.

(Embodiment 2)
-Optical scanning device-
<Elastic member>
FIG. 9 is a perspective view showing the deflector housing section 203 according to the second embodiment. Note that in FIG. 9, illustration of the upper lid 202 is omitted.

A rectangular tube-shaped through hole 505B is provided in the center of the elastic member 500, passing through the elastic member 500 in the thickness direction (see FIG. 9). The through hole 505B penetrates between the housing section top surface 205 and the upper lid 202.

The through hole 505B in the second embodiment plays the role of efficiently dissipating the heat of the deflector 220 to the outside of the optical scanning device 200, similar to the through hole 505A in the first embodiment. The opening area of the hole 505B is set larger than that of the through hole 505A. Therefore, the heat radiation area secured by the through hole 505B is larger than the heat radiation area secured by the through hole 505A. Therefore, in the second embodiment including the through hole 505B, the heat dissipation performance of more efficiently dissipating the heat of the deflector 220 to the outside of the optical scanning device 200 is improved.

By setting the opening area of the through hole 505B to be larger than that of the through hole 505A, the contact area where the elastic member 500 in the second embodiment contacts the housing section top surface 205 and the upper lid 202 becomes small. As a result, in the second embodiment, compared to the first embodiment, the repulsive force that the accommodating part top surface 205 and the upper lid 202 receive from the elastic member 500 is reduced, and the elastic member 500 Since the vibration energy absorbed through the elastic member 500 is reduced, the vibration damping performance of the elastic member 500 is reduced, but as described above, the heat dissipation performance is improved.

(Embodiment 3)
-Optical scanning device-
<Elastic member>
FIG. 10 is a sectional view showing a longitudinal section of an elastic member 500 according to the third embodiment. Note that in FIG. 10, illustration of the through hole (through hole 505A or through hole 505B) is omitted.

The elastic member 500 has a through hole (the through hole 505A or the through hole 505B) as in the first embodiment or the second embodiment, but in the third embodiment, the elastic member 500 has a through hole (the through hole 505A or the through hole 505B). The first elastic layer 501 is in contact with the upper lid 202, and the second elastic layer 502 is in contact with the upper lid 202. In this way, when the elastic member 500 is formed by laminating a plurality of elastic layers, the damping performance of the elastic member 500 can be optimized. Specifically, it is as follows. In the third embodiment, one side of the elastic member 500 is in contact with the top surface 205 of the housing section made of resin, and the other side is in contact with the top lid 202 made of metal. Resin materials and metal materials generally have different vibration characteristics, and the arrangement of the housing top surface 205 and the top lid 202 in the optical scanning device 200 is also different, so that the amplitude of the housing top surface 205 is The amplitude tends to be larger than the amplitude of the upper lid 202. Therefore, with the elastic member 500 made of a single rubber material, it may be difficult to appropriately damp the vibrations of the top surface 205 of the housing section 205 and the vibrations of the top lid 202, respectively. Therefore, if the elastic member 500 is made up of a first elastic layer 501 that is in contact with the top surface 205 of the accommodating part and a second elastic layer 502 that is in contact with the top lid 202, the accommodating part It becomes possible to appropriately damp the vibrations of the top surface 205 and the top lid 202. In the third embodiment, the hardness of the first elastic layer 501 is set higher than the hardness of the second elastic layer 502. As a result, the top surface 205 of the accommodating section, which has a large amplitude, is reliably suppressed by the first elastic layer 501 having high hardness, and the vibration energy from the top surface 205 of the accommodating section 205 and the top lid 202 is absorbed by the second elastic layer 502. Thus, an elastic member 500 that exhibits a higher vibration damping effect is realized.

Hereinafter, the present invention will be described in further detail in conjunction with examples of the present invention.

(Example 1)
In order to confirm the vibration damping performance of the elastic member 500, a vibration measurement test was conducted. The elastic member 500 was made of neoprene rubber sponge with a rubber hardness of 25±5, the top surface 205 of the housing part was made of PC+ABS (polycarbonate+acrylonitrile butadiene styrene) resin, and the top lid 202 was made of SECC sheet metal. In the case where the elastic member 500 is provided (hereinafter referred to as "the case with the elastic member") and in the case where the elastic member 500 is excluded (hereinafter referred to as the "case without the elastic member"), the storage part top Vibrations at the surface 205 (indicated as "the top surface of the deflector accommodating section" in the table below) and the top cover 202 (indicated as "the top cover of the optical scanning device" in the table below) were measured using an acceleration pickup. . The results are shown in the table below.

Regarding the top surface 205 of the housing part, the vibration (acceleration) without the elastic member was 0.33 mm/s ² , while the vibration (acceleration) with the elastic member was up to 0.07 mm/s ^2. Reduced. By providing the elastic member 500, the vibration on the top surface 205 of the housing section was reduced by approximately 78%.

In the upper lid 202, the vibration (acceleration) without the elastic member was 0.27 mm/s ² , whereas the vibration (acceleration) with the elastic member was reduced to 0.09 mm/s ² . By providing the elastic member 500, vibrations in the upper lid 202 were reduced by approximately 66%.

From the above results, it is clear that the elastic member 500, which is pressed between the top surface 205 of the storage section 205 and the top lid 202 and provided at the center of the top surface 205 of the storage section, causes the vibration of the top surface 205 of the storage section and the vibration of the top lid 202. It can be concluded that the vibrations of the deflector 220 and the vibration of the housing 201 are suppressed by suppressing these vibrations comprehensively and efficiently.

The above embodiments and examples are illustrative in all respects and are not the basis for restrictive interpretation. Therefore, the technical scope of the present invention should not be interpreted only by the above-described embodiments and examples, but should be defined based on the claims. In addition, all changes within the meaning and scope of equivalents to the scope of the claims are included.

100 Image forming apparatus 200 Optical scanning device 201 Housing 201a Bottom plate 201b Side plate 201d Side plate 201e Side plate 201f Second window 202 Upper lid 203 Deflector housing 203a Opening 204 Lower lid 205 Accommodation top surface 205a L-shaped protrusion 206a Accommodation side side 206b Side surface 206c Side surface 206d Side surface 210 Input optical system 211 Light source 211a Terminal 212 Collimator lens 213 Aperture member 214 Cylindrical lens 215 Light source reflection mirror 220 Deflector 221 Deflection scanning board 222 Deflection scanning motor 222a Rotating shaft 223 Deflection Scanning member 223a Reflection surface 230 Output optical system 231 fθ lens 232 Reflection mirror for beam detection 232a Reflection mirror for beam detection 233 Beam detection lens 234 Beam detection section 240 Substrate 241 Cable connection section 290 Control substrate 500 Elastic member 501 First elastic layer 502 Second elastic layer 505A Through hole 505B Through hole 3 Photosensitive drum (scanned object)
L Light beam R Rotation direction W Longitudinal direction X1 Main scanning direction

Claims (7)

a deflector that deflects and scans the light;
A hollow case with a lid,
a covered hollow deflector accommodating part inscribed in the casing and accommodating the deflector;
an elastic member held in pressure contact between the lid of the deflector accommodating portion and the lid of the casing ;
In a plan view of the deflector accommodating section, the elastic member is a part of the top surface of the lid section, and is provided at the center of the top surface of the lid section, and the elastic member is a part of the top surface of the lid section. The position is determined by the protrusion provided on the top surface of the
The elastic member may have a through hole penetrating between the lid of the deflector housing and the lid of the casing.
An optical scanning device characterized by: The optical scanning device according to claim 1,
An optical scanning device characterized in that the elastic member is formed by laminating a plurality of elastic layers. a deflector that deflects and scans the light;
A hollow case with a lid,
a covered hollow deflector accommodating part inscribed in the casing and accommodating the deflector;
an elastic member held in pressure contact between the lid of the deflector accommodating portion and the lid of the casing ;
In a plan view of the deflector accommodating section, the elastic member is a part of the top surface of the lid section, and is provided at the center of the top surface of the lid section, and the elastic member is a part of the top surface of the lid section. The position is determined by the protrusion provided on the top surface of the
The elastic member is formed by laminating a plurality of elastic layers.
An optical scanning device characterized by: The optical scanning device according to claim 3,
The optical scanning device is characterized in that the elastic member has a through hole penetrating between the lid of the deflector accommodating portion and the lid of the casing. The optical scanning device according to claim 4,
The elastic member is formed by laminating a plurality of elastic layers,
The elastic layer includes a first elastic layer that is in contact with the lid of the deflector accommodating section, and a second elastic layer that is in contact with the lid of the casing,
An optical scanning device characterized in that the hardness of the first elastic layer is higher than the hardness of the second elastic layer. In the optical scanning device according to any one of claims 1 to 5,
An optical scanning device characterized in that the lid portion of the casing is made of metal. An image forming apparatus comprising the optical scanning device according to any one of claims 1 to 6 .

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