JP6410126B2 - SOUND ABSORBING DEVICE, ELECTRONIC DEVICE, AND IMAGE FORMING DEVICE - Google Patents

Description

  The present invention relates to a sound absorbing device using a Helmholtz resonator, and an electronic apparatus and an image forming apparatus using the same.

  In an electrophotographic image forming apparatus, driving sounds of various driving units and sounds when a polygon mirror rotates are generated during image formation. Patent Documents 1 and 2 describe an image forming apparatus including a sound absorbing device using a Helmholtz resonator as a configuration capable of absorbing sound generated during image formation.

（Δｒ：開口端補正）
ヘルムホルツ共鳴器を用いた吸音装置では、所望の吸音効果を得るためには、空洞部は連通部の開口部以外は外部に対して密閉されている必要がある。 The Helmholtz resonator is formed by a hollow portion having a certain volume and a communication portion that communicates the hollow portion with the outside. When the volume of the cavity is “V”, the opening area of the communication part is “S”, the length of the communication part in the communication direction is “H”, and the sound velocity is “c”, the sound absorption using the Helmholtz resonator is performed. The frequency “f” of the sound absorbed by the device is obtained by the following equation (1).

(Δr: Open end correction)
In a sound absorbing device using a Helmholtz resonator, in order to obtain a desired sound absorbing effect, the cavity needs to be sealed from the outside except for the opening of the communicating portion.

In Patent Documents 1 and 2, a first member that forms a wall surface provided with a communicating portion that communicates with the outside of a wall surface that forms a cavity portion of a Helmholtz resonator, and a second member that forms another wall surface of the cavity portion To form a cavity.
In such a configuration in which the hollow portion is formed by two members, there is a possibility that a gap may be generated in the joint portion due to manufacturing errors or assembly errors of the members. If a gap occurs in the joint, the sealing of the cavity cannot be ensured and a desired sound absorbing effect cannot be obtained.
Such a problem is not limited to the sound absorbing device used in the image forming apparatus, and may be caused by a sound absorbing device using a Helmholtz resonator.

  The present invention has been made in view of the above problems, and the object thereof is as follows. That is, a sound absorbing device using a Helmholtz resonator that suppresses a reduction in the sound absorbing effect due to the occurrence of a gap at the joint between the members forming the cavity, and can efficiently absorb sound, And providing an electronic apparatus and an image forming apparatus including the same.

In order to achieve the above object, a first aspect of the invention provides a sound absorbing device using a Helmholtz resonator, wherein a wall surface provided with a communication portion communicating with the outside is formed among the wall surfaces forming a cavity of the Helmholtz resonator. And a second member that forms the other wall surface of the cavity,
A joining portion between the first member and the second member is formed by a concave shape portion and an end portion of a side wall into which a tip portion enters the concave portion of the concave shape portion, and between the concave portion and the end portion. pinched and is characterized in that it comprises a fixing means for fixing the gap closing member for closing a gap between said first member and said second member, and said first member and said second member.

  According to the present invention, in a sound absorbing device using a Helmholtz resonator, it is possible to efficiently suppress sound by suppressing a reduction in sound absorbing effect caused by a gap formed at a joint between members forming a cavity. There is an excellent effect of becoming.

1 is a schematic sectional view schematically showing a sound absorbing device according to the present invention. 1 is a schematic configuration diagram of a copying machine according to an embodiment of the present invention. FIG. 2 is a schematic configuration diagram in the vicinity of a photoconductor in the copier. FIG. 3 is a perspective explanatory view showing a state where a front opening / closing cover of the copier is opened. FIG. 5 is a perspective view of the copying machine with the left side exterior cover removed from the state shown in FIG. 4. FIG. 6 is an explanatory perspective view of the copying machine in the state of FIG. 5 as viewed from an angle at which an inner surface of the front housing to which the front inner cover is fixed is visible. Explanatory drawing of the attachment position of the sound-absorbing device in a front inner cover. The expansion perspective view of a sound absorption device. The schematic sectional drawing of the state which attached the sound-absorbing apparatus to the front inner cover. The schematic diagram of the sound-absorbing device using a Helmholtz resonator. The schematic sectional drawing which showed typically the sound-absorbing device of the 3 body structure which consists of three members. The schematic sectional drawing which shows typically the sound-absorbing device of the structure where a sealing member contacts only the front end surface of a main body side wall part. The schematic sectional drawing which shows typically the sound-absorbing apparatus which forms a several Helmholtz resonator by a pair of sound-absorbing cover members and a sound-absorbing main body member. Explanatory drawing of a sound absorption cover member, (a) is perspective explanatory drawing, (b) is a bottom view, (c) is side sectional drawing in the DD cross section in (b). Explanatory drawing of a sound absorption main body member, (a) is perspective explanatory drawing, (b) is a top view, (c) is a sectional side view in the DD cross section in (b). Explanatory drawing of a sound absorption cap member, (a) is a perspective explanatory drawing, (b) is side sectional drawing. Explanatory drawing of the concave shape part in the lower surface of a sound absorption cover member. The schematic sectional drawing which showed typically the sound-absorbing apparatus which concerns on a modification.

  Hereinafter, an embodiment of an electrophotographic copying machine (hereinafter simply referred to as “copying machine 500”) as an image forming apparatus to which the present invention is applied will be described. In this embodiment, a monochrome image forming apparatus will be described as an example of the copying machine 500, but the present invention can be similarly applied to a known color image forming apparatus.

First, the configuration of the copying machine 500 will be described.
FIG. 2 is a schematic configuration diagram of the entire copying machine 500 according to the present embodiment. In FIG. 2, the image reading apparatus 200 is mounted on the copying machine main body 100 of the copying machine 500, and the copying machine main body 100 is placed on a recording paper bank 300. Mounted on the image reading apparatus 200 is an automatic document feeder 400 that is configured to be rotatable about the back side (the back side in the drawing) as a fulcrum.

  Inside the copying machine main body 100, a drum-shaped photoconductor 10 is provided as a latent image carrier. FIG. 3 is a schematic configuration diagram in which the vicinity of the photoconductor 10 is enlarged. As shown in FIG. 3, around the photosensitive member 10, a static elimination lamp 9, a charging device 11 using a charging roller, a developing device 12, a transfer unit 13, and a cleaning device 14 having a photosensitive member cleaning blade 8 are arranged. Yes. The developing device 12 uses a polymerized toner produced by a polymerization method as a toner, and attaches the polymerized toner to an electrostatic latent image on the photoconductor 10 using a developing roller 121 as a developer carrier. Visualize.

  The transfer unit 13 includes a transfer belt 17 wound around two roller members, a first belt stretching roller 15 and a second belt stretching roller 16, and the transfer belt 17 is photosensitive at the transfer position B. It is pressed against the peripheral surface of the body 10.

  Foreign matter such as residual toner and paper dust remaining on the transfer belt 17 after the recording paper P is separated is transferred to the first belt stretching roller 15 via the transfer belt 17 provided in the transfer belt cleaning unit C. Then, the cleaning blade 18 is scraped off.

  Further, the copying machine main body 100 is provided with a toner replenishing device 20 for replenishing the developing device 12 with new toner on the left side of the charging device 11 and the cleaning device 14 in the drawing.

  Further, the copying machine main body 100 is provided with a recording paper transport device 60 that transports the recording paper P sent from the recording paper cassette 61 of the recording paper bank 300 to the discharge stack section 39 via the transfer position B. The recording paper transport device 60 transports the recording paper P along the supply path R1 or the manual feed path R2 and the recording paper transport path R. On the recording paper conveyance path R, a registration roller pair 21 is provided upstream of the transfer position B in the recording paper conveyance direction.

  On the other hand, a thermal fixing device 22 is provided on the downstream side in the recording paper conveyance direction of the recording paper conveyance path R with respect to the transfer position B. The heat fixing device 22 performs heat and pressure fixing by sandwiching the recording paper P between a heating roller 30 as a heating member and a pressure roller 32 as a pressure member.

  A discharge branch claw 34, a discharge roller 35, a first pressure roller 36, a second pressure roller 37, and a roller 38 with a stiffness are provided further downstream in the recording paper conveyance direction of the heat fixing device 22. In addition, a discharge stack unit 39 for stacking the recording paper P on which the image has been formed through the heat fixing device 22 is also provided.

  Further, the copying machine main body 100 is provided with a switchback device 42 on the right side in the drawing. The switchback device 42 reverses the reversing path R3 branched from the position where the discharge branch claw 34 of the recording paper transport path R is disposed, and the recording paper P passing through the reversing path R3 again. The recording paper P is conveyed along a re-conveying path R4 that leads to the position of the roller pair 21. A switchback roller pair 43 is provided in the reverse path R3, and a plurality of recording paper transport roller pairs 66 are provided in the re-transport path R4.

  As shown in FIG. 2, the copying machine main body 100 is provided with a laser writing device 47 on the left side of the developing device 12 in the drawing. The laser writing device 47 includes a scanning optical system such as a laser light source (not shown), a polygon mirror 48 that is a rotating polygon mirror for scanning, a polygon motor 49, and an fθ lens (not shown).

The image reading apparatus 200 includes a light source 53, a plurality of mirrors 54, an imaging optical lens 55, an image sensor 56 such as a CCD image sensor, and the like, and a contact glass 57 is provided on the upper surface thereof.
The automatic document feeder 400 is provided with a document setting table (not shown), and a document stacking table (not shown) is provided at the document discharge position. The automatic document conveying device 400 includes a plurality of document conveying rollers (not shown), and the document is conveyed by the document conveying rollers from the document setting table to the reading position on the contact glass 57 of the image reading device 200 (not shown). It is conveyed to the document stacking table.

  In the recording paper bank 300, a plurality of recording paper cassettes 61 for storing recording paper P such as paper or OHP film as recording materials are provided. Each recording paper cassette 61 is provided with a call roller 62, a supply roller 63, and a separation roller 64, respectively. On the right side of the recording paper cassette 61 in the drawing, the above-described supply path R1 leading to the recording paper conveyance path R of the copying machine main body 100 is formed. This supply path R1 is also provided with several recording paper transport roller pairs 66 for transporting the recording paper P.

  The copying machine main body 100 is provided with a manual paper feed unit 68 on the right side in FIG. The manual feed unit 68 is provided with a manual feed tray 67 that can be opened and closed. The manual feed path R2 that guides the recording paper P set on the manual feed tray 67 to the recording paper transport path R is formed. ing. Similarly to the recording paper cassette 61, the manual paper feeding unit 68 is also provided with a calling roller 62, a supply roller 63, and a separation roller 64.

Next, the operation of the copying machine 500 will be described.
When copying using the copying machine 500, first, a main switch (not shown) is turned on, and a document is set on a document setting table of the automatic document feeder 400. In the case of a book document, the automatic document feeder 400 is opened, a document is set directly on the contact glass 57 of the image reading device 200, and the automatic document feeder 400 is closed and pressed.

Thereafter, when a start switch (not shown) is pressed, when an original is set on the automatic document feeder 400, the original is moved onto the contact glass 57 through the document feeding path by the document feeding roller, and then the image reading device 200 is driven. To do. The original content is read and discharged onto the original stack table. On the other hand, when the document is set directly on the contact glass 57, the image reading device 200 is immediately driven to read the content of the document.
When reading the content of the original, the image reading apparatus 200 irradiates the original surface on the contact glass 57 with light from the light source 53 while moving the light source 53 along the contact glass 57. Then, the reflected light is guided to the imaging optical lens 55 by a plurality of mirrors 54 and put into the image sensor 56, and the document content is read by the image sensor 56.

  In the copying machine 500, the photosensitive member 10 is rotated by a photosensitive member driving motor (not shown) at the same time as reading the document content. First, the charging device 11 uniformly charges the surface of the photoconductor 10 to about −1000 [V], for example. Next, laser writing is performed by irradiating the photosensitive member 10 with laser light from the laser writing device 47 in accordance with the content of the original read by the image reading device 200 described above, thereby forming an electrostatic latent image on the surface of the photosensitive member 10. The surface potential of the portion irradiated with the laser light (latent image portion) is, for example, 0 [V] to −200 [V]. Thereafter, the developing device 12 attaches toner to the electrostatic latent image to make it visible.

  In the copying machine 500, at the same time when the start switch is pressed, the recording paper P is sent out by the calling roller 62 from the one corresponding to the selected size among the plurality of recording paper cassettes 61 provided in the recording paper bank 300. Then, the fed recording sheet P is separated one by one by the supply roller 63 and the separation roller 64, and the one sheet is guided to the supply path R 1, and is guided to the recording sheet conveyance path R by the recording sheet conveyance roller pair 66. . The recording paper P conveyed to the recording paper conveyance path R hits the registration roller pair 21 and is stopped.

When the manual paper feed unit 68 is used, the manual feed tray 67 is opened and the recording paper P is set thereon. Also in this case, the recording paper P is transported to the manual feed path R2 by the calling roller 62, the supply roller 63, and the separation roller 64, and is guided to the recording paper transport path R by the recording paper transport roller pair 66. It stops against the registration roller pair 21.
In this way, the recording paper P stopped by the registration roller pair 21 starts to rotate at the timing when the leading edge of the visible toner image of the photoreceptor 10 enters the transfer position B. The pair 21 is sent to the transfer position B.

  The recording paper P fed to the transfer position B is transferred with the toner image on the photoreceptor 10 by the transfer unit 13 and carries the toner image on the surface thereof. The residual toner remaining on the surface of the photoreceptor 10 after the transfer is removed by the cleaning device 14, and the residual potential on the photoreceptor 10 is also removed by the charge eliminating lamp 9. By removing the residual potential, the surface potential is averaged to a reference potential of 0 [V] to −150 [V], and is prepared for the next image formation starting from the charging device 11.

  On the other hand, the recording paper P carrying the toner image is conveyed by the transfer belt 17 and enters the heat fixing device 22. Then, heat and pressure are applied while being conveyed between the heating roller 30 and the pressure roller 32, and the toner image on the recording paper P is fixed. Thereafter, the recording paper P is stiffened by the discharge roller 35, the first pressure roller 36, the second pressure roller 37, and the roller 38 with a stiffness, discharged onto the discharge stack portion 39, and stacked there. .

  When images are to be formed on both sides of the recording paper P, the discharge branch claw 34 is switched, the toner image is transferred and fixed on one side of the recording paper P, and then the recording paper P is removed from the recording paper conveyance path R. Enter in reverse path R3. The recording paper P put in the reversing path R3 is transported by the recording paper transport roller pair 66 and put into the switchback position 44, and then switched back by the switchback roller pair 43, and this time is put in the re-transporting path R4 and recorded. The paper transport roller pair 66 guides the recording paper transport path R again. Then, the toner image is transferred to the opposite surface of the recording paper P that has passed through the re-transport path R4 in the same manner as described above.

FIG. 4 is a perspective explanatory view of the copying machine 500 with the front opening / closing cover 101 opened.
The copying machine 500 shown in FIG. 4 is in a state in which the automatic document feeder 400 and the optical system inside the image reading apparatus 200 are removed. Further, by opening the front opening / closing cover 101 which is an exterior cover, the front inner cover 102 which is an interior cover is exposed. Further, a toner bottle (not shown) provided in the toner replenishing device 20 is removed, and a bottle set hole 20a, which is a portion where the toner bottle is inserted in the front inner cover 102, is opened. A recording paper cassette outer cover 61 a having a handle for pulling out the recording paper cassette 61 is disposed below the front opening / closing cover 101 in the copying machine 500.

FIG. 5 is a perspective view of the copying machine 500 in which the left side exterior cover 103 is removed from the state shown in FIG. 4 and the left side case 520 is exposed. FIG. 6 is a perspective view of the copier 500 in the state of FIG. 5 as viewed from an angle at which the inner surface of the front casing 510 provided inside the front inner cover 102 and to which the front inner cover 102 is fixed is visible. FIG.
As shown in FIG. 6, the copier 500 includes a sound absorbing device 600 using a Helmholtz resonator at a position facing the laser writing device 47 inside the front surface.

  FIG. 7 is an explanatory diagram of a mounting position of the sound absorbing device 600 on the front inner cover 102. As shown in FIG. 7, the front inner cover 102 includes a sound absorbing device installation portion 160 on its inner surface. Then, as indicated by an arrow in FIG. 7, the sound absorbing device 600 is attached and fixed to the sound absorbing device installation portion 160, and the front inner cover 102 is fixed to the front casing 510. As a result, as shown in FIG. 6, the sound absorbing device 600 protrudes inward from the sound absorbing device installation opening 510 a which is an opening formed in the front housing 510.

  FIG. 8 is an enlarged perspective view of the sound absorbing device 600, and FIG. 9 is a schematic cross-sectional view of the sound absorbing device 600 attached to the front inner cover 102. The sound absorbing device 600 is a sound absorbing device using a Helmholtz resonator, and includes three members, a sound absorbing main body member 610, a sound absorbing cover member 620, and a sound absorbing cap member 630, as shown in FIGS. The sound absorbing cover member 620 is fixed to the sound absorbing main body member 610 by a cover fixing screw 640, and the sound absorbing main body member 610 is fixed to the front inner cover 102 by the main body fixing screw 650.

FIG. 10 is a schematic diagram of a sound absorbing device 600 using a Helmholtz resonator.
As shown in FIG. 10, the Helmholtz resonator is shaped like a container with a narrow entrance, and is configured by a hollow portion 601 having a certain volume and a communication portion 603 smaller than the hollow portion 601. Absorbs incoming specific frequency sound.
The volume of the cavity 601 is “V”, the opening area of the opening 602 in the communication portion 603 is “S”, the length of the communication portion 603 is “H”, the sound velocity is “c”, and the sound absorption frequency in the sound absorbing device 600 is set. When “f” is assumed, the following equation (1) is established.

“Δr” in the equation (1) is an opening end correction, and “Δr = 0.6r” is generally used when the radius when the cross section of the communication portion 603 is circular is “r”.
As shown in the equation (1), the frequency of the sound absorbed by the sound absorbing device 600 can be obtained from the volume V of the hollow portion 601, the length H of the communicating portion 603, and the opening area S of the communicating portion 603.

  In the copying machine 500, various sounds such as a driving sound of a driving motor that transmits rotational driving to various rollers, a moving sound of moving members such as various rollers, and a rotating sound of the polygon mirror 48 of the laser writing device 47 are generated. . Such a sound may be transmitted to the outside of the copier 500, resulting in noise that causes discomfort to surrounding people. By forming the sound absorbing device 600 in accordance with the frequency of the sound that is desired to be suppressed from being transmitted to the outside among such sounds that can become noise, the sound absorbing device 600 can absorb the sound that can become noise.

FIG. 11 is a schematic cross-sectional view schematically showing a three-component sound absorbing device 600 including three members, a sound absorbing main body member 610, a sound absorbing cover member 620, and a sound absorbing cap member 630.
The sound absorbing cover member 620 that forms the wall surface provided with the communication portion 603 and the sound absorbing cap member 630 that forms the communication portion 603 are separate members. Thus, by replacing the sound absorbing cap member 630 with a different shape, the length H of the communication portion 603 and the value of the opening area S of the communication portion 603 in the equation (1) can be easily changed. The sound absorption frequency can be changed.

  A sound absorbing device 600 using a Helmholtz resonator mutes sound of a specific frequency as a noise countermeasure for electronic equipment. In such a sound absorbing device 600, in an image forming apparatus having a plurality of printing speeds using a common structure, the frequency of sound that can become noise varies depending on the printing speed. In the configuration in which the sound absorbing cap member 630 is a separate member with respect to the sound absorbing main body member 610 and the sound absorbing cover member 620 that form the wall surface of the hollow portion 601, the sound absorbing cap member 630 is replaced, so that sound absorption corresponding to each printing speed is achieved. The frequency can be changed cheaply and easily.

  Further, in the configuration in which the wall surface of the cavity 601 is formed by two members, the sound absorbing main body member 610 and the sound absorbing cover member 620, as in the sound absorbing device 600 shown in FIG. 11, there is a gap between the joints due to manufacturing errors and assembly errors of the members. May occur. If a gap occurs in the joint, the sealing of the cavity cannot be ensured and a desired sound absorbing effect cannot be obtained.

  To solve such a problem, as shown in FIG. 11, a concave shape portion 621 is provided at a joint portion of the sound absorption cover member 620 with the sound absorbing main body member 610, and the concave shape portion 621 is a sealing member made of an elastic material. It is conceivable to provide 660. By providing the sealing member 660 in the concave portion 621, when the sound absorbing cover member 620 and the sound absorbing main body member 610 are joined, the sealing member 660 is sandwiched between the two members and deformed to close the gap. it can.

  However, if only the sealing member 660 is provided in the concave shape portion 621, the shape of the hollow portion 601 changes or a gap is generated in the joint portion when the sound absorbing cover member 620 vibrates with respect to the sound absorbing main body member 610. As a result, the desired sound absorption effect may not be obtained.

Next, features of the sound absorbing device 600 according to the present invention will be described.
FIG. 1 is a schematic cross-sectional view schematically showing a sound absorbing device 600 according to the present invention.
A sound absorbing device 600 shown in FIG. 1 includes a sound absorbing cover member 620 that forms a wall surface provided with a communication portion 603 that communicates with the outside of the wall surfaces that form the cavity portion 601, and a sound absorbing device that forms the other wall surface of the cavity portion 601. A main body member 610. In addition, a sealing member 660 that is sandwiched between the sound absorbing cover member 620 and the sound absorbing main body member 610 at the concave shape portion 621 and deforms along the surfaces of the sound absorbing cover member 620 and the sound absorbing main body member 610 by being pressurized is provided. . Furthermore, the sealing member 660 is sandwiched between the sound absorbing cover member 620 and the sound absorbing main body member 610, and the cover fixing screw that fixes the sound absorbing cover member 620 and the sound absorbing main body member 610 in a state where the sealing member 660 is deformed more than before pressurization. 640.

As in the sound absorbing device 600 shown in FIG. 1, by fixing the sound absorbing cover member 620, the sound absorbing main body member 610, and the cover fixing screw 640, pressure is applied to the joint between the sound absorbing cover member 620 and the sound absorbing main body member 610. Then, the sealing member 660 disposed in the concave portion 621 that is the joint portion is crushed to close the gap at the joint portion between the sound absorbing cover member 620 and the sound absorbing main body member 610, and the sealing performance of the cavity portion 601 can be improved. Increases sound absorption effect.
Further, since the sealing member 660 made of an elastic material is crushed and the sound absorbing cover member 620 and the sound absorbing main body member 610 are fixed, vibrations of the sound absorbing cover member 620 with respect to the sound absorbing main body member 610 can be reduced, so that a higher sound absorbing effect can be obtained. You can expect.

  If a fixing member such as the cover fixing screw 640 is inside the hollow portion 601, the function as the Helmholtz resonator is deteriorated. In the sound absorbing device 600 shown in FIG. 1, since the cover fixing screw 640 that is a fixing member is installed outside the cavity portion 601, the function as a Helmholtz resonator is reduced due to the provision of the fixing member. Can be prevented.

  In the sound absorbing device 600 shown in FIG. 1, the sealing member 660 is pushed by the tip of the main body side wall portion 611 that is a portion forming the hollow portion 601 of the sound absorbing main body member 610 and deformed along the surface thereof, and the main body side wall portion 611. It is touching up to the side. As a result, the sealing member 660 is in a state of closing the gap between the main body side wall portion 611 of the sound absorbing main body member 610 and the concave shape portion 621 of the sound absorbing cover member 620.

FIG. 12 is a schematic cross-sectional view schematically showing a sound absorbing device 600 having a configuration in which the sealing member 660 contacts only the front end surface of the main body side wall 611. FIG. 12A is an explanatory view before the sound absorbing main body member 610 and the sound absorbing cover member 620 are joined, and FIG. 12B is a sound absorbing device obtained by joining the sound absorbing main body member 610 and the sound absorbing cover member 620. It is explanatory drawing of the state which formed 600. FIG.
The sealing member 660 may have any shape that prevents air from passing through the joint between the sound absorbing main body member 610 and the sound absorbing cover member 620. In the sound absorbing device 600 shown in FIG. 1, the range that contacts not only the front end surface of the main body side wall portion 611 but also the side surface is widened. However, as shown in FIG. The structure which the sealing member 660 contacts so that a contact area may spread may be sufficient.

  FIG. 13 is a schematic cross-sectional view schematically showing a sound absorbing device 600 that forms a plurality of Helmholtz resonators by a pair of sound absorbing cover members 620 and a sound absorbing main body member 610. In the sound absorbing device 600 shown in FIG. 13, the sound absorbing effect is enhanced by forming two or more hollow portions 601 by a pair of the sound absorbing cover member 620 and the sound absorbing main body member 610.

Next, each member which comprises the sound-absorbing device 600 of this embodiment shown in FIG. 8 is demonstrated.
FIG. 14 is an explanatory view of a sound absorbing cover member 620 constituting the sound absorbing device 600, FIG. 14 (a) is a perspective explanatory view, FIG. 14 (b) is a bottom view, and FIG. 14 (c) is FIG. 14 (b). It is a side sectional view in the DD section inside.
FIG. 15 is an explanatory view of a sound absorbing main body member 610 constituting the sound absorbing device 600, FIG. 15 (a) is a perspective explanatory view, FIG. 15 (b) is a top view, and FIG. 15 (c) is FIG. It is a side sectional view in the DD section inside.
FIG. 16 is an explanatory view of a sound absorbing cap member 630 constituting the sound absorbing device 600, FIG. 16 (a) is a perspective explanatory view, and FIG. 16 (b) is a side sectional view.
FIG. 17 is an explanatory diagram of the concave portion 621 in which the position of the concave portion 621 on the lower surface of the sound absorbing cover member 620 shown in FIG.

  As shown in FIG. 14, in the sound absorbing cover member 620, three cavity upper surface portions 623 that form the upper surface of the cavity portion 601 are each surrounded by a concave shape portion 621, and an upper surface opening 622 is formed in each cavity upper surface portion 623. Is the shape formed. In addition, a cover-side screw hole 640 a into which the cover fixing screw 640 is inserted is formed in the outer portion of the concave shaped portion 621 with respect to the cavity upper surface portion 623.

  As shown in FIG. 15, the sound absorbing main body member 610 includes a main body side fixing portion 612 in which a main body side screw hole 640 b into which the cover fixing screw 640 is inserted is formed outside the main body side wall portion 611 that forms the side surface of the cavity portion 601. Is provided. Further, a main body fixing screw hole 650 a into which a main body fixing screw 650 that fixes the sound absorbing main body member 610 to the front inner cover 102 is inserted is provided in another portion outside the main body side wall portion 611.

  As shown in FIG. 16, the sound absorbing cap member 630 becomes a shell with a cap flange portion 632 that forms the communication portion 603 and a cap flange portion 631 that abuts against the upper surface of the sound absorbing cover member 620. By changing the length of the cap flange portion 632 of the sound absorbing cap member 630, the value of the length H of the communication portion 603 can be changed, and by changing the inner diameter of the cylindrical cap flange portion 632, the communication portion The value of the opening area S of 603 can be changed.

  The sealing member 660 is provided in the concave portion 621 of the sound absorbing cover member 620. As the sealing member 660, a configuration in which a sealing material such as a resin material is filled in the concave shape portion 621 by caulking, or a configuration in which a sealing member that matches the shape of the concave shape portion 621 is prepared in advance and installed in the concave shape portion 621. Can be mentioned.

  As the sealing member 660, an elastic body such as rubber can be used. However, if the sound absorbing cover member 620 and the sound absorbing main body member 610 are deformed when they are joined and the joint is sealed, they are not limited to those that are restored when pressure is released after deformation, such as an elastic body, A member such as clay that remains deformed even when the pressure is released may be used. However, if the elastic member is used as the sealing member 660, the shape of the sealing member 660 is restored when the sound absorbing cover member 620 is removed from the sound absorbing main body member 610. Therefore, the sound absorbing cover member 620 and the sound absorbing main body member 610 again It can also be used as it is for bonding. That is, the sealing member 660 can be used repeatedly.

When assembling the sound absorbing device 600, the sound absorbing main body member 610 is covered with the sound absorbing cover member 620 provided with the sealing member 660 so that the main body side screw hole 640b faces the cover side screw hole 640a. Then, the cover fixing screw 640 is inserted from the cover side screw hole 640a and tightened. The cover fixing screw 640 of the present embodiment is a wood screw with a sharp tip, and the main body side screw hole 640b has a smaller diameter than the shaft portion of the cover fixing screw 640. By tightening the cover fixing screw 640, the cover fixing screw 640 enters the main body side fixing portion 612 while cutting the screw in the main body side screw hole 640b.
In the present embodiment, the sound absorbing cover member 620 is moved to the sound absorbing main body member 610 in a state where the sealing member 660 is elastically deformed by tightening until the upper end surface of the main body side fixing portion 612 hits the lower surface of the sound absorbing cover member 620. It can be fixed.

  Further, one of the cap flange portions 632 sandwiching the cap flange portion 631 in the sound absorbing cap member 630 is inserted into the upper surface opening 622 of the sound absorbing cover member 620. Thereby, the sound absorbing cap member 630 can be fixed to the sound absorbing cover member 620, and the sound absorbing device 600 shown in FIG. 8 can be assembled.

As shown in FIG. 7, the copying machine 500 of the present embodiment is configured such that the front inner cover 102 and the sound absorbing device 600 are separated and the sound absorbing device 600 is attached to the front inner cover 102. However, the sound absorbing device 600 may be configured such that the front inner cover 102 is also used as the sound absorbing cover member 620 or the sound absorbing main body member 610.
As shown in FIGS. 14, 15, and 17, the screwing portion between the sound absorbing cover member 620 and the sound absorbing main body member 610 forming the sound absorbing device 600 is outside the hollow portion 601, and the sound absorbing effect of the sound absorbing device 600 is obstructed. It has a configuration that does not.

  Further, as shown in FIG. 17, a sealing member 660 is provided so as to surround each cavity upper surface portion 623 at a joint portion between the sound absorbing cover member 620 and the sound absorbing main body member 610. Thereby, it is possible to prevent a gap that allows the cavity 601 and the outside from communicating with each other at the joint.

[Modification]
FIG. 18 is a schematic cross-sectional view schematically showing a sound absorbing device 600 according to a modification of the present invention. The sound absorbing device 600 of the above-described embodiment has a configuration using screwing by the cover fixing screw 640 as the fixing means, but the fixing means is not limited to this.

  The sound absorbing device 600 according to the modified example includes fixing means for fixing by fixing a fixing claw 625 provided on the sound absorbing cover member 620 to a claw receiving convex portion 615 provided on the sound absorbing main body member 610. In the modification example in which the fixing claw 625 is used for fixing, the sound absorbing cover member 620 can be fixed to the sound absorbing main body member 610 in a state where the sealing member 660 is elastically deformed, similarly to the screw fixing of the above-described embodiment. Yes. By elastically deforming the sealing member 660 so as to be crushed, the sealing property of the cavity 601 can be ensured, and the sound absorption effect is enhanced. Moreover, since it can fix only by hooking the fixed nail | claw 625, there also exists an advantage that it is easy to assemble | attach.

  In the screw fixing configuration as in the above-described embodiment, it takes time and effort to tighten the screw at the time of assembly as compared with the configuration in which the fixing claw 625 is hooked and fixed as in the modification. However, the screw fixing can be fixed more firmly and the sealing performance is improved, so that the sound absorbing effect can be further improved. Further, after the fixing claw 625 is hooked and temporarily fixed, the final fixing may be performed by screwing.

As shown in FIG. 6, the sound absorbing device 600 according to the present embodiment is disposed at a position facing the laser writing device 47, and generates rotation sound of the polygon mirror 48 of the laser writing device 47 and driving sound of the polygon motor 49. It can absorb sound efficiently. However, the sound absorbing device to which the present invention is applied may be appropriately disposed at another position of the image forming apparatus.
In the present embodiment, the case where the electronic apparatus including the sound absorbing device is an image forming apparatus has been described. However, the electronic device including the sound absorbing device may be configured to include a sound source unit that generates sound during operation and a sound absorbing device that absorbs sound emitted from the sound source unit. For example, the present invention can be applied to an electronic apparatus other than the image forming apparatus.

What has been described above is merely an example, and the present invention has a specific effect for each of the following modes.
(Aspect A)
In the sound absorbing device using the Helmholtz resonator such as the sound absorbing device 600, a wall surface provided with a communication portion such as the communication portion 603 communicating with the outside is formed among the wall surfaces forming the cavity portion of the Helmholtz resonator such as the cavity portion 601. A first member such as a sound absorbing cover member 620 and a second member such as a sound absorbing main body member 610 that forms the other wall surface of the cavity, and the first member at the joint between the first member and the second member In a state where the gap closing member such as a sealing member 660 that is sandwiched between the second member and is pressurized and deformed to close the gap between the first member and the second member and the gap closing member is deformed. Fixing means such as a cover fixing screw 640 for fixing the first member and the second member.
According to this, as demonstrated about the said embodiment, the 1st member which forms a cavity part by fixing a 1st member and a 2nd member in the state which changed the gap obstruction | occlusion member arrange | positioned in the junction part. It is possible to close the gap at the joint portion between the second member and the second member. As a result, it is possible to suppress the reduction of the sound absorption effect due to the occurrence of a gap at the joint portion between the members forming the hollow portion, and to efficiently absorb the sound.

(Aspect B)
In the aspect A, the fixing means performs fixing with a screw such as a cover fixing screw 640.
According to this, as described in the above-described embodiment, the sound absorption effect as a Helmholtz resonator in the sound absorbing device such as the sound absorbing device 600 can be improved because it is firmly tightened by screwing and the sealing degree is increased.

(Aspect C)
In any of the aspects A and B, the fixing means pulls the claw shape such as the fixing claw 625 provided on one of the first member such as the sound absorbing cover member 620 or the second member such as the sound absorbing main body member 610 to the other. It is fixed by hanging.
According to this, as described in the modification, by pressing the first member and the second member so as to be close to each other, the claw shape is caught and the first member and the second member can be easily fixed. It can be carried out. Thereby, the assembly | attachment property which assembles a sound-absorbing device can be aimed at.

(Aspect D)
In any one of the aspects A to C, a communication part forming member such as a sound absorbing cap member 630 formed by a member different from the first member such as the sound absorbing cover member 620 is formed. Prepare.
According to this, as described in the above embodiment, the sound absorbing frequency in the sound absorbing device such as the sound absorbing device 600 can be easily changed at low cost by replacing the communicating portion forming member with a different shape.

(Aspect E)
In any one of the aspects A to D, a plurality of Helmholtz resonators are formed by the first member such as the sound absorbing cover member 620 and the second member such as the sound absorbing main body member 610.
According to this, as described in the above embodiment, the sound absorbing effect is improved by forming a cavity such as two or more cavities 601 by a pair of the first member and the second member. be able to.

(Aspect F)
In any one of the aspects A to E, the fixing means such as the cover fixing screw 640 is outside the wall surface of the main body side wall part 611 or the like that forms the cavity part such as the cavity part 601.
According to this, as described in the above embodiment, the fixing means does not affect the shape of the hollow portion, and it is possible to suppress the sound absorption effect from being reduced due to the provision of the fixing means.

(Aspect G)
In an electronic device such as a copying machine 500 that includes sound absorbing means for absorbing sound during operation, a sound absorbing device such as the sound absorbing device 600 according to any one of aspects A to F is used as the sound absorbing means.
According to this, as described in the above embodiment, it is possible to enhance the sound absorption effect of the sound generated during the operation of the electronic device.

(Aspect H)
The electrophotographic image forming apparatus such as the copying machine 500 has the configuration of the electronic device described in the aspect G.
According to this, as described in the above embodiment, it is possible to enhance the sound absorption effect of the sound generated during the operation of the image forming apparatus.

DESCRIPTION OF SYMBOLS 1 Photoconductor 8 Photoconductor cleaning blade 9 Static elimination lamp 10 Photoconductor 11 Charging device 12 Developing device 13 Transfer unit 14 Cleaning device 15 First belt stretching roller 16 Second belt stretching roller 17 Transfer belt 18 Cleaning blade 20 Toner supply device 20a Bottle set hole 21 Registration roller pair 22 Heat fixing device 30 Heating roller 32 Pressure roller 34 Discharge branch claw 35 Discharge roller 36 First pressure roller 37 Second pressure roller 38 Roller with stiffness 39 Discharge stack unit 42 Switchback device 43 switchback roller pair 44 switchback position 47 laser writing device 48 polygon mirror 49 polygon motor 53 light source 54 mirror 55 imaging optical lens 56 image sensor 57 contact glass 60 recording paper transport Device 61 Recording paper cassette 62 Call roller 63 Supply roller 64 Separation roller 66 Recording paper transport roller pair 67 Manual feed tray 68 Manual paper feed unit 100 Copier body 101 Front opening / closing cover 102 Front inner cover 103 Left side exterior cover 121 Developing roller 160 Sound absorption Device installation unit 200 Image reading device 300 Recording paper bank 400 Automatic document feeder 500 Copier 510 Front housing 510a Sound absorber installation opening 520 Left side housing 600 Sound absorber 601 Cavity 602 Opening 603 Communication unit 610 Sound absorption body Member 611 Body side wall portion 612 Body side fixing portion 615 Claw receiving convex portion 620 Sound absorbing cover member 621 Concave shape portion 622 Upper surface opening portion 623 Cavity upper surface portion 625 Fixing claw 630 Sound absorbing cap member 631 Cap collar 632 Cap flange Part 640 Cover fixing screw 640a Cover side screw hole 640b Main body side screw hole 650 Main body fixing screw 650a Main body fixing screw hole 660 Sealing member B Transfer position C Transfer belt cleaning part P Recording paper R Recording paper transport path R1 Supply path R2 Manual feed path R3 Reverse path R4 Re-transport path

JP 2000-235396 A JP 2001-117451 A JP 2012-71662 A JP 2012-8458 A

Claims (8)

In a sound absorbing device using a Helmholtz resonator,
A first member that forms a wall surface provided with a communicating portion that communicates with the outside of the wall surface that forms the cavity of the Helmholtz resonator, and a second member that forms the other wall surface of the cavity,
Forming a joint portion between the first member and the second member by a concave shape portion and an end portion of a side wall into which a tip portion enters the concave portion of the concave shape portion;
Sandwiched between said recess and said end portion, a gap blockage member for closing a gap between said first member and said second member,
Absorbing device, characterized in that it comprises a fixing means for fixing the said first member and said second member. The sound absorbing device according to claim 1,
A sound-absorbing device, wherein the fixing means performs fixing with screws. The sound absorbing device according to claim 1 or 2,
The sound absorbing device according to claim 1, wherein the fixing means performs fixing by hooking a claw shape provided on one of the first member or the second member to the other. The sound absorbing device according to any one of claims 1 to 3,
A sound absorbing device, comprising: a communication part forming member that forms the communication part and is formed by a member different from the first member. The sound absorbing device according to any one of claims 1 to 4,
A plurality of Helmholtz resonators are formed by a set of the first member and the second member. The sound absorbing device according to any one of claims 1 to 5,
The sound absorbing device, wherein the fixing means is outside a wall surface forming the hollow portion. In electronic equipment equipped with sound absorbing means for absorbing sound during operation,
An electronic apparatus using the sound absorbing device according to any one of claims 1 to 6 as the sound absorbing means. In an electrophotographic image forming apparatus,
An image forming apparatus comprising the configuration of the electronic device according to claim 7.

Images