JP2007163879A - Noise reduction mechanism of image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a noise reduction mechanism of an image forming apparatus, which is capable of preventing an influence upon an image of vibrations occurring in a process cartridge during printing operation. <P>SOLUTION: In the image forming apparatus having a process cartridge attached thereto and detached therefrom, a sound absorbing member is stuck to the inside of a cartridge door which is opened and closed when the process cartridge is attached/detached. The sound absorbing member is stuck so as to fill a space between the process cartridge and the cartridge door, and the sound absorbing member is deflected by contact with the process cartridge and is brought into close contact with the process cartridge to press the process cartridge when the cartridge door is closed. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a noise reduction mechanism used in an image forming apparatus such as a printer / copier using an electrophotographic process.

  An example of an image forming apparatus using an electrophotographic process will be described with reference to FIG. The image forming apparatus 1 using an electrophotographic process forms an image on a sheet by the following series of operations. The sheet fed by the feed roller 101 is conveyed to the image forming unit. In the image forming unit, the photosensitive drum 103 provided in the process cartridge 2 is charged by a charging device (not shown) such as a charging roller in the process cartridge 2. A latent image is formed by irradiating the photosensitive drum 103 with light generated by a semiconductor laser or the like installed in the polygon scanner 102. Then, toner is adsorbed to the latent image, and the toner is transferred to a recording medium by the transfer roller 104 to form an image. The sheet onto which the image has been transferred is fixed by the fixing device 105 and discharged onto the discharge tray 106.

  As a charging method in such an image forming apparatus, a contact charging method is often used in which a roller is brought into contact with the photoconductor 103 to be charged. In the contact charging method using a roller, a DC voltage or a DC voltage is applied to a roller in contact with the photoconductor 103 so that an AC voltage is superimposed on the roller, and the surface of the photoconductor 103 is charged to a constant potential by the potential. At this time, the charging roller and the photoconductor 103 are repeatedly contacted and peeled at a constant cycle by the AC voltage superimposed on the DC voltage. This may cause a sound called a charging sound. The generation factor of the charging sound is described in detail in Patent Document 1.

  In many cases, the process cartridge is opened and closed by opening and closing the cartridge door 3 as shown in FIG. The process cartridge is attached and detached by engaging the photosensitive member support portion 108 and the boss-shaped convex portion 109 installed in the process cartridge with the cartridge guide 107 and moving along the cartridge guide. The inserted process cartridge 2 is fixed by a cartridge fixing member 6.

The image forming apparatus having the detachable process cartridge 2 is provided with a cartridge door 3 that can be opened and closed to detach the process cartridge 2. The cartridge door 3 is often lightly weighted so as to reduce the degree of sealing with the main body when the cartridge door is closed so as not to be a burden on the user during the opening / closing operation. In such a case, there is a case where a gap is generated between the main body and the cartridge door, and a charging sound generated inside the main body is likely to leak to the outside. In order to prevent such sound leakage, a technique has been proposed in which noise is reduced by attaching a fibrous or felt-like sound absorbing member having a sound absorbing effect to the inside of the main body exterior. (See Patent Document 2)
Japanese Patent Laid-Open No. 5-35050 JP 2002-365985 A

  As described in the above conventional example, in a contact charging type image forming apparatus using a roller, when charging is performed by superimposing an AC voltage on a DC voltage, contact and peeling between the roller and the photosensitive member are performed. By repeating the above, a sound called a charging sound is generated. In order to reduce these sounds, when a sound-absorbing member is affixed inside the exterior, the cost increases.

  The object according to the present proposal is to prevent sound generated inside the image forming apparatus from being emitted from between the main body exterior portion and the cartridge door by attaching a sound absorbing member to the inside of the cartridge door. Further, by providing the sound absorbing member with a process cartridge fixing function or a pressing function, the fixing member and the pressing member can be omitted, and the noise of the image forming apparatus can be reduced without increasing the cost.

  According to the first aspect of the present invention, the sound-absorbing member is affixed to the inside of the cartridge door with a double-sided tape or the like, so that the sound generated inside the image forming apparatus is emitted from between the main body exterior and the cartridge door. To prevent it. The process cartridge is pressed and fixed by the sound absorbing member toward the inside of the main body, so that the fixing member of the process cartridge can be omitted.

  According to the second aspect of the present invention, the sound-absorbing member is affixed to the inside of the cartridge door with a double-sided tape or the like, so that the sound generated inside the image forming apparatus is emitted from between the main body exterior and the cartridge door. To prevent it. When the cartridge door is closed, the process cartridge is pushed toward the inside of the main body by the sound absorbing member, so that the cartridge pressing member for preventing poor insertion can be omitted.

  As described above, according to the present invention, it is possible to provide a function of fixing the process cartridge to the sound absorbing member attached to the inside of the cartridge door. In addition, it is possible to prevent the image from being affected by the vibration generated in the process cartridge during the printing operation. Further, the sound absorbing member attached to the inner side of the cartridge door can have a function of pressing the process cartridge. Then, when the process cartridge is not inserted to a predetermined position, it is possible to prevent poor insertion by pushing down to the predetermined position. Thus, by providing the sound absorbing member with a fixing function or a pressing function, it is possible to reduce the noise without increasing the cost by omitting the fixing member and the pressing member of the process cartridge.

Example 1
In the first embodiment of the present invention, a sound absorbing member is attached to the gap between the process cartridge and the cartridge door, thereby preventing sound generated from the process cartridge. Further, by pressing the process cartridge with the sound absorbing member, the process cartridge is prevented from being detached from a predetermined position by a driving force received from the main body driving unit.

  This example will be described with reference to FIGS.

  1A and 1B are cross-sectional views of the main body of the image forming apparatus. FIG. 1A is a view when the cartridge door is closed, and FIG. 1B is a view when the cartridge door is opened. 4 is a sound absorbing member. Here, the same components as those in the conventional example (FIG. 7) and the components having the same actions are designated by the same reference numerals, and redundant description is omitted.

  FIG. 2 shows the numerical value of the frequency peak around 1200 Hz, which is the frequency of the charging sound when the image forming apparatus of a certain product is in operation.

  FIG. 3 is an enlarged view of a process cartridge pressing portion by a sound absorbing member. (A) is a figure just before a sound-absorbing member and a process cartridge contact, (b) is a figure which a sound-absorbing member and a process cartridge are in contact, and is pressing a process cartridge with a sound-absorbing member. In this figure, reference numeral 5 denotes a deformed portion of the sound absorbing member when the process cartridge is pressed by the sound absorbing member.

  A part of the cartridge door 3 is fitted to the upper part of the apparatus main body, and the cartridge door 3 is installed so as to be rotatable about the fitting portion. When the cartridge door 3 is opened, the process cartridge 2 is exposed. When removing the process cartridge 2 from the main body, the cartridge door 3 is opened, and the exposed process cartridge 2 is pulled out obliquely upward. Thereby, the process cartridge 2 is pulled out along the cartridge guide 107 and taken out. Further, when the process cartridge 2 is inserted, a protrusion 109 for engaging the photosensitive member support 108 and the cartridge guide installed in the process cartridge 2 is inserted obliquely from above so as to engage with the cartridge guide 107. . Then, the cartridge guide 107 is mounted by being pushed into the apparatus main body.

  When the process cartridge 2 is inserted into the apparatus main body and the cartridge door 3 is closed, there is a gap between the process cartridge 2 and the cartridge door 3. An unpleasant sound such as a charging sound is generated from the process cartridge 2 when the apparatus main body is driven, and the sound is radiated to the outside of the apparatus main body through a space between the process cartridge 2 and the cartridge door 3.

  In order to prevent such sound from being radiated out of the apparatus main body, a sound absorbing member 4 is used by using a double-sided tape (not shown) inside the cartridge door 3 so as to fill a space between the process cartridge 2 and the cartridge door 3. Is attached as shown in FIG. FIG. 2 shows the result of measuring the sound during operation of the apparatus main body when foamed rubber is used for the sound absorbing member 4. The frequency peak around 1200 Hz, which is the frequency of the charging sound, is reduced by about 5 dB when the sound absorbing member is attached, compared to when no sound absorbing member is present. In this way, it is possible to reduce unpleasant sounds by attaching the sound absorbing member. The measurement conditions at this time are shown in FIG. The noise level meter 202 was installed in the front direction of the printer main body at a position 100 mm above and 100 mm forward from the surface of the printer main body, and the central position of the printer main body in the left-right direction.

  When the sound absorbing member 4 is attached, the sound absorbing member 4 is installed so that a part of the sound absorbing member 4 is in contact with the process cartridge 2 with the cartridge door 3 closed (FIG. 1A). At this time, when the process cartridge 2 is pressed as shown in FIG. 3, a part of the sound absorbing member 4 (the deformed portion 5 of the sound absorbing member shown in FIG. 3A) is deformed so that the process cartridge 2 is in close contact with the process cartridge 2. Then, the process cartridge 2 is pressed into the main body. When the sound absorbing member having a hardness of about 50 ° (Asker C) is used, the pushing pressure when the cartridge is pressed can be about 2 kgf. In this way, the process cartridge 2 is pressed against the inside of the main body by the sound absorbing member 4. Then, it is possible to continue printing without being influenced by the vibration generated in the process cartridge 2 due to the driving force received by the process cartridge 2 from the main body drive unit. This eliminates the need to install a member for fixing the process cartridge 2 (fixing member 6 shown in FIG. 7A) or the like, and can be omitted.

  In this way, the sound absorbing member is stuck between the process cartridge and the cartridge door, and is pressed against the process cartridge so that a part of the sound absorbing member is deformed. Accordingly, it is possible to shield the sound generated from the process cartridge and reduce the main body noise, and to prevent the process cartridge from being unintentionally detached from the main body. As a result, the process cartridge fixing member can be omitted, and the noise can be reduced without increasing the cost.

(Example 2)
In the second embodiment of the present invention, a sound absorbing member is attached to the gap between the process cartridge and the cartridge door. This prevents sound generated from the process cartridge, and when the process cartridge is not inserted up to a predetermined position, it is pushed down to the predetermined position by pressing the cartridge with its sound absorbing member, thereby preventing poor insertion. is there.

  This example will be described with reference to FIGS.

  4A and 4B are cross-sectional views of the main body of the image forming apparatus. FIG. 4A is a view when the cartridge door is opened, FIG. 4B is a view in the middle of closing the cartridge door, and FIG. It is. Here, the same reference numerals are given to components having the same components and actions as those in the drawings (FIGS. 1 and 7) described in the conventional example and the first embodiment, and redundant description is omitted.

  FIG. 5 shows a numerical value of a frequency peak around 1200 Hz, which is the frequency of the charging sound when the image forming apparatus is in operation.

  Also in this example, a sound absorbing member is affixed to the inside of the cartridge door 3 as in Example 1. In this example, foamed urethane is used as the sound absorbing member 4 and affixed to the inside of the cartridge door 3 with a double-sided tape (not shown). FIG. 5 shows the results of measuring the sound during operation of the apparatus main body when urethane foam is used. As for the foamed urethane, the sound during operation is reduced by about 5 dB as compared with the case without the sound absorbing member as with the foamed rubber. The measurement conditions at this time are shown in FIG. The noise level meter 202 was installed in the front direction of the printer main body at a position 100 mm above and 100 mm forward from the surface of the printer main body, and the central position of the printer main body in the left-right direction.

  When urethane foam is affixed to the inside of the cartridge door 3, the sound absorbing member is affixed so that a part of the sound absorbing member comes into contact with the process cartridge 2 with the cartridge door 3 closed as shown in FIG. 4A, when the process cartridge 2 is not sufficiently inserted as shown in FIG. 4A, the sound absorbing member 4 is attached to the process cartridge as shown in FIG. 4B when the cartridge door 3 is closed. 2 above. Then, by pushing down the cartridge door 3, the process cartridge 2 is pushed in, so that the process cartridge can be inserted to a predetermined position.

  In this way, by attaching the sound absorbing member to the gap between the process cartridge and the cartridge door, the sound generated from the process cartridge is shielded and the main body noise is reduced. Further, when the process cartridge is not sufficiently inserted, the process cartridge is pushed down to a predetermined position by closing the cartridge door, thereby preventing the process cartridge from being poorly inserted. Further, since the process cartridge can be pushed in using the sound absorbing member, the member for pushing in the process cartridge described in the conventional example can be omitted, and the noise can be reduced without increasing the cost. Become.

2A and 2B are cross-sectional views of the image forming apparatus to which the sound absorbing member is attached according to the first embodiment of the present invention, in which FIG. The figure which showed the effect of the sound absorption member based on 1st Example of this invention FIG. 4 is an enlarged view of the cartridge pressing portion by the sound absorbing member according to the first embodiment of the present invention, where (a) is when the cartridge is not pressed, and (b) is when the cartridge is pressed. FIG. 6 is a cross-sectional view of an image forming apparatus to which a sound absorbing member is attached according to a second embodiment of the present invention, where (a) is when the cartridge door is opened, (b) is in the middle of closing the cartridge door, and (c) is closed. Time The figure which showed the effect of the sound absorption member based on 2nd Example of this invention The figure which showed the measurement conditions of the operating sound based on the 1st and 2nd Example of this invention Sectional drawing of the image forming apparatus which concerns on a prior art example

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image forming apparatus main body 2 Process cartridge 3 Cartridge door 4 Sound absorption member 5 Deformation part of the sound absorption member for pressing a process cartridge 6 Cartridge fixing member 101 Paper feed roller 102 Polygon scanner 103 Photosensitive drum 104 Transfer roller 105 Fixing device 106 Exhaust Paper tray 107 Cartridge guide 108 Photosensitive member support section 109 Convex section engaged with the cartridge guide 201 The apparatus main body at the time of operating sound measurement 202 The noise meter used for measuring the operating sound 203 The tripod for fixing the noise meter 204 The apparatus main body is installed Stand to do

Claims (3)

A detachable process cartridge that constitutes a part of an image forming unit that forms an image on a sheet-like recording medium, a cartridge door that can be partially opened and closed to detach the process cartridge, and a cartridge An image forming apparatus comprising: a cartridge pressing member that presses a part of the process cartridge in a state where the cartridge door is closed inside the door.
The cartridge pressing member is a sound absorbing member having a sound absorbing effect in a region of 500 Hz to 2000 Hz, and the cartridge pressing member is affixed to the inside of the cartridge door with a double-sided tape or an adhesive so as to fill a gap between the process cartridge and the cartridge door. An image forming apparatus.   The image forming apparatus according to claim 1, wherein the cartridge pressing member is an elastic body.   3. The cartridge pressing member is affixed to the inside of the cartridge door with a double-sided tape or an adhesive, and the cartridge pressing member is closed while pushing the process cartridge toward the inside of the main body when the cartridge door is closed. The image forming apparatus described in 1.

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