JP5070182B2 - Image forming apparatus - Google Patents

Description

  The present invention relates to an image forming apparatus such as a digital copying machine and a laser printer, and more particularly to an image forming apparatus in which a part of an exterior member of the apparatus main body has a multiple structure.

  In an image forming apparatus using an electrophotographic system such as a copying machine, a printer, or a FAX, the surface of an image carrier such as a photosensitive drum is uniformly charged by a charging device, and the image is carried by exposure (light irradiation) from an exposure device. In general, a process in which an electrostatic latent image formed on a body is visualized by a developing device, the toner image is transferred onto a recording medium, and then a fixing process is performed by a fixing device.

  Here, since a considerable amount of heat is generated from the power supply board that supplies power to the fixing device and each part of the device, the heat from these members causes the inside of the device to become high temperature, which adversely affects the image quality and malfunctions the device. It becomes the cause of. Therefore, a configuration is adopted in which an intake fan is provided near the inside of the exterior member and the inside of the apparatus is cooled by taking in cold air outside the apparatus via a louver formed in the exterior member.

  On the other hand, it is necessary to replace replacement parts such as a waste toner collection tank, to clean the charging unit, and to perform maintenance and inspection inside the apparatus. Therefore, a part of the exterior member of the device has a double structure, and the workability is improved by opening only the outer exterior member when replacing the waste toner collection tank or during internal maintenance and inspection. ing.

  However, in the above configuration, when the louver is formed in the double structure portion, the air inside the apparatus is also drawn into the intake fan through the gap between the outer and inner exterior members, so that the outside air is efficiently drawn There was a problem that it could not be captured. In addition, an air flow is also generated around the waste toner collection tank by the intake fan, and the toner adhering to the waste toner collection tank is drawn into the apparatus from the gap between the outer and inner exterior members through the louver of the inner exterior member. There was also a problem of contaminating the inside of the apparatus.

  Here, the intake fan that introduces outside air into the apparatus has been described as an example, but the exhaust fan that discharges the air inside the apparatus to the outside also leaks the air flow from the gap of the exterior member and the exhaust efficiency decreases. There was a similar problem.

As a method for preventing airflow leakage and improving the intake or exhaust efficiency by the fan, for example, in Patent Document 1, a sponge material such as urethane foam is stuck between a duct and an exterior cover to prevent wind leakage. A method is disclosed. Patent Document 2 discloses an image forming apparatus in which a rib protruding into a space from a fan opening to a louver is integrally formed on an exterior cover. On the other hand, Patent Document 3 discloses an image forming apparatus in which exhaust efficiency is improved by fitting an exhaust fan unit into an opening of a rib of an exterior cover with a seal plate interposed therebetween.
Japanese Patent Laid-Open No. 3-105366 (see FIG. 10) JP-A-6-318028 JP 2006-208842 A

  However, in the method of Patent Document 1, since the sponge material is used, the number of parts is increased, and in order to surely prevent the leakage of the air flow, the accuracy of attaching the sponge material is required, and the assembling work is complicated. It was. In addition, the sponge material may be peeled off during assembly. Further, when the louver is provided on the opening / closing cover, there is a problem that the opening / closing cover is not completely closed due to the restoring force of the sponge material, and the opening / closing cover is deformed or damaged.

  On the other hand, in the method of Patent Document 2, if the gap between the outer periphery of the fan and the rib is made small, it is necessary to increase the mounting accuracy of the fan, and there is a problem that the assembly workability is lowered. Further, since the rib is disposed in the immediate vicinity of the fan, the rib may resonate due to the rotation of the fan, which may cause noise. The method of Patent Document 3 requires a sealing plate, which increases the number of parts and increases the gap between the exterior and the fan, which is disadvantageous from the viewpoint of downsizing and space saving of the device.

  SUMMARY OF THE INVENTION In view of the above problems, the present invention provides an image forming apparatus in which leakage of airflow from a gap between exterior members having a multiple structure is prevented with a simple configuration and intake or exhaust efficiency by a fan is improved. Objective.

  In order to achieve the above object, the present invention includes a fan that introduces external air into the apparatus body or exhausts the air inside the apparatus to the outside, and a louver through which an air flow generated by the fan passes. And a plurality of exterior covers that face each other so that the positions of the respective louvers overlap with each other, wherein each of the exterior covers protrudes so as to surround the louver on the facing exterior cover side. The ribs are formed integrally with each other, and the ribs face each other so as to overlap each other with a predetermined gap in the radial direction between the outer covers, and the outer cover facing the tip of the ribs A gap is formed between the two.

  According to the present invention, in the image forming apparatus configured as described above, a gap between the front end of the rib and the outer cover facing the rib is 1 mm or less.

  According to the present invention, in the image forming apparatus configured as described above, the exterior cover includes a first exterior cover and a second exterior cover that supports the first exterior cover so that the first exterior cover can be opened and closed, and the fan includes the first exterior cover. An air intake fan that introduces external air into the apparatus main body through a first louver formed on the exterior cover and a second louver formed on the second exterior cover. An opening for exposing the disposed waste toner recovery tank is formed.

  According to the first configuration of the present invention, the ribs integrally formed so as to surround the louver face each other so as to overlap each other in the radial direction between the respective exterior covers. Inflow or leakage of the air flow into the gap of the exterior cover can be suppressed, and intake or exhaust efficiency by the fan can be improved with a simple configuration. Further, since the ribs, the outer cover facing the ribs, and the ribs formed on the facing outer cover do not come into contact with each other, there is no possibility that the assembling workability of the outer cover is lowered.

  According to the second configuration of the present invention, in the image forming apparatus having the first configuration, the labyrinth effect is enhanced by setting the gap between the front end of the rib and the facing outer cover to be 1 mm or less. The airflow generated in the gap can be sufficiently weakened.

  Also, according to the third configuration of the present invention, in the image forming apparatus having the first or second configuration, the waste toner collection tank is simply opened by the opening formed in the second exterior cover. Can be easily replaced, and waste toner adhering to the waste toner recovery tank can be effectively prevented from being contaminated by being drawn into the intake fan through the gap between the first and second exterior covers.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a side sectional view showing the internal structure of the image forming apparatus of the present invention. In an image forming apparatus (for example, a printer) 100, when performing an image forming operation, a photosensitive drum 5 that rotates clockwise in the drawing is uniformly charged by a charging unit 4, and an exposure unit (laser scanning unit) based on document image data. Etc.) An electrostatic latent image is formed on the photosensitive drum 5 by the laser beam from 7, and a developer (hereinafter referred to as toner) is attached to the electrostatic latent image by the developing unit 8 to form a toner image.

  The toner is supplied to the developing unit 8 from the toner container 9. The image data is transmitted from a personal computer (not shown) or the like. Further, a static elimination device (not shown) for removing residual charges on the surface of the photosensitive drum 5 is provided on the downstream side of the cleaning device 19.

  A sheet is conveyed from the sheet feeding cassette 10 or the manual feed tray 11 via the sheet conveying path 12 and the registration roller pair 13 toward the photosensitive drum 5 on which the toner image is formed as described above, and the transfer roller 14 (image The toner image formed on the surface of the photosensitive drum 5 is transferred onto the sheet by the transfer unit. The sheet on which the toner image has been transferred is separated from the photosensitive drum 5 and conveyed to a fixing unit 15 having a fixing roller pair 15a to fix the toner image. The sheet that has passed through the fixing unit 15 is conveyed to the upper part of the apparatus by the sheet conveying path 16 and is discharged from the discharge roller pair 17 to the discharge tray 18.

  FIG. 2 is an external perspective view of the image forming apparatus of the present invention. The exterior of the printer 100 includes a cassette cover 35 disposed on the front of the apparatus, a manual tray cover 36, a side cover 37 (second exterior cover) disposed on both sides of the apparatus, and top covers 38a and 38b disposed on the top of the apparatus. The opening / closing cover 40 (first exterior cover) is supported by the side cover 37 so as to be openable and closable, and a back cover (not shown). In FIG. 2, only the side cover 37 on one side (left side of the apparatus) is shown.

  The cassette cover 35 is attached to the paper feed cassette 10 (see FIG. 1), and the surface side thereof is exposed to the outside to constitute a part of the exterior surface of the main body of the image forming apparatus 100 (here, the apparatus front surface). The manual feed tray cover 36 is attached to the outside of the manual feed tray 11 (see FIG. 1), and can be opened and closed up and down with the lower end portion as a fulcrum. In the opened state (the state shown in FIG. 1) The manual feed tray 11 can be used, and when it is turned upward and closed (the state shown in FIG. 2), it forms an exterior surface on the front surface of the apparatus together with the cassette cover 35.

  A discharge tray 18 is formed on the top cover 38a, and an operation unit (not shown) on which operation buttons, a display panel, and the like are mounted is disposed at the right end of the top cover 38b. An opening / closing cover 40 is provided outside the side cover 37, and a first louver 41 is formed on the opening / closing cover 40.

  3 is a perspective view of the image forming apparatus showing a state in which the opening / closing cover 40 is opened, and FIG. 4 is an enlarged view of the periphery of the opening / closing cover 40 and the side cover 37 in FIG. The opening / closing cover 40 is supported on the side cover 37 by a lower rotation fulcrum 40a and an upper rotation fulcrum 40b, and can be opened and closed horizontally around a rotation axis connecting the rotation fulcrums 40a and 40b. ing.

  In addition, an opening 37 a is formed at a substantially central portion of the side cover 37. When the opening / closing cover 40 is closed as shown in FIG. 2, the opening 37a is covered with the opening / closing cover 40, and the opening / closing cover 40 is opened as shown in FIG. 3, and the waste toner inside the apparatus is collected via the opening 37a. Maintenance such as replacement of the tank 42 and cleaning of the charging unit 4 is performed. When exchanging the drum unit including the photosensitive drum 5 and the developing unit 8, the upper surface cover 38a is removed and the operation is performed from above the apparatus.

  As shown in FIG. 4, an annular first rib 45 projects from the inner surface of the opening / closing cover 40 so as to surround the first louver 41. Further, the side cover 37 is formed with a second louver 43 at a position overlapping the first louver 41 when the opening / closing cover 40 is closed, and an annular second rib 47 is provided so as to surround the second louver 43. Has been.

  FIG. 5 is a longitudinal sectional view of the vicinity of the first louver 41 in FIG. When the open / close cover 40 is closed as shown in FIG. 2, the first louver 41, the second louver 43, and the intake fan 50 are sequentially arranged from the outside of the apparatus (left side of FIG. 5). Outside air is drawn into the apparatus through the louver 41 and the second louver 43, and is used for cooling the fixing unit 15 (see FIG. 1) and the like.

  Further, the inner circumferential length of the first rib 45 surrounding the first louver 41 is formed larger than the outer circumferential length of the second rib 47 surrounding the second louver 43, and the first rib 45 surrounds the second rib 47. Are arranged as follows. That is, the first rib 45 and the second rib 47 overlap each other at a predetermined interval in the radial direction. Further, a gap is formed between the tip of the first rib 45 and the side cover 37 and between the tip of the second rib 47 and the opening / closing cover 40.

  FIG. 6 is a partially enlarged view inside the broken-line circle S in FIG. The air outside the apparatus linearly passes through the first louver 41 of the opening / closing cover 40 and the second louver 43 of the side cover 37 as indicated by solid arrows, and is drawn into the intake fan 50 (see FIG. 5), and is fixed to the fixing unit. 15 is sent to each part of the apparatus. On the other hand, the suction force of the intake fan 50 also acts on the air present in the gap between the side cover 37 and the opening / closing cover 40, but passes through the first rib 45 and the second rib 47 in an S-shape as indicated by broken line arrows. In the meantime, the air flow is weakened by the labyrinth effect.

  With this configuration, since cold air outside the apparatus can be efficiently drawn into the apparatus, the cooling effect of the heat radiation source in the apparatus is improved. In addition, since waste toner attached to the waste toner collection tank 42 is less likely to be drawn into the intake fan 50 through the gap between the side cover 37 and the opening / closing cover 40, it is possible to effectively prevent contamination inside the apparatus due to waste toner. it can.

  Further, the narrower the gap a1 between the tip of the first rib 45 and the side cover 37 and the gap a2 between the tip of the second rib 47 and the opening / closing cover 40, the higher the labyrinth effect and weaken the air flow. On the other hand, if the first rib 45 and the side cover 37 or the second rib 47 and the opening / closing cover 40 are in contact, the opening / closing cover 40 may not be completely closed due to deformation or dimensional tolerance of the side cover 37 or the opening / closing cover 40. There is sex. Therefore, it is preferable to provide gaps a1 and a2 of 1 mm or less, and more preferably about 0.5 mm.

  Note that the labyrinth effect increases as the distance between the first rib 45 and the second rib 47 is reduced. However, as with the gaps a1 and a2, the deformation amount and dimensional tolerance of the side cover 37 or the opening / closing cover 40 are taken into consideration. To decide.

  In addition, this invention is not limited to the said embodiment, A various change is possible in the range which does not deviate from the meaning of this invention. For example, in the above-described embodiment, the double structure exterior member in which the opening / closing cover 40 is provided outside the side cover 37 has been described, but the present invention can be applied to exterior members having a triple structure or more. Further, instead of the intake fan 50, an exhaust fan that exhausts hot air inside the apparatus to the outside may be provided.

  In the above embodiment, the first rib 45 is disposed on the radially outer side of the second rib 47, but the first rib 45 may be disposed on the radially inner side of the second rib 47. good. Furthermore, if at least one of the first ribs 45 or the second ribs 47 is formed, and the first ribs 45 and the second ribs 47 are alternately arranged in the gap between the side cover 37 and the opening / closing cover 40, the more A remarkable labyrinth effect is obtained.

  The present invention is not limited to a printer, and can be applied to various image forming apparatuses such as analog and digital monochrome copying machines, color copying machines, and facsimiles.

  The present invention can be used for an image forming apparatus having a multiple structure exterior member opposed to a plurality of exterior covers, and having a louver serving as an air flow passage in the multiple structure portion. An annular rib projecting so as to surround the louver is integrally formed on the facing exterior cover side, and each rib is opposed to each other so as to overlap each other at a predetermined interval in the radial direction. A gap was formed between the front end and the facing outer cover.

  As a result, the labyrinth effect of the opposing ribs suppresses the flow of air from the gap of the outer cover or the leakage of the air flow to the gap of the outer cover, and the intake or exhaust efficiency by the fan can be improved with a simple configuration. An image forming apparatus can be provided simply and at low cost.

  In addition, since the ribs and the outer cover facing the ribs and the ribs formed on the facing outer cover do not come into contact with each other, it is possible to prevent the assembly workability of the outer cover from being lowered. In order to enhance the labyrinth effect, it is preferable that the gap between the front end of the rib and the facing outer cover is 1 mm or less.

  In addition, an exterior cover is configured by using an intake fan that introduces external air into the apparatus main body, and an exterior cover including a first exterior cover and a second exterior cover that supports the first exterior cover so that the first exterior cover can be opened and closed. The second exterior cover is formed with an opening through which the waste toner collection tank disposed inside the apparatus is exposed, so that the waste toner collection tank can be easily replaced and the inside of the apparatus can be drawn by drawing the waste toner from the intake fan. Thus, the image forming apparatus can suppress toner contamination.

FIG. 1 is a schematic cross-sectional view showing an overall configuration of an image forming apparatus of the present invention. FIG. 2 is an external perspective view of the image forming apparatus of the present invention. FIG. 3 is an external perspective view of the image forming apparatus showing a state in which an opening / closing cover is opened. FIG. 4 is an enlarged view of the periphery of a side cover and an opening / closing cover in FIG. 3. These are the longitudinal cross-sectional views of the 1st louver vicinity in FIG. These are the elements on larger scale in the broken-line circle | round | yen S in FIG.

Explanation of symbols

35 Cassette cover 36 Bypass tray cover 37 Side cover (second exterior cover)
38a, 38b Top cover 40 Open / close cover (first exterior cover)
41 First louver 42 Waste toner recovery tank 43 Second louver 45 First rib 47 Second rib 50 Intake fan 100 Printer

Claims (3)

A fan that introduces external air into the device body or exhausts air inside the device to the outside;
An exterior member in which a plurality of exterior covers formed with louvers through which an air flow generated by the fan passes are opposed to each other so that the positions of the louvers overlap;
In each of the exterior covers, an annular rib protruding so as to surround the louver is integrally formed on each of the exterior covers, and the ribs are formed between the exterior covers. An image forming apparatus, wherein the image forming apparatus is opposed to each other so as to overlap each other at a predetermined interval in the radial direction, and a gap is formed between the front end of the rib and the outer cover facing the rib.   The image forming apparatus according to claim 1, wherein a gap between the end of the rib and the outer cover facing the rib is 1 mm or less.   The exterior cover includes a first exterior cover and a second exterior cover that supports the first exterior cover so that the first exterior cover can be opened and closed. The fan includes a first louver and a second louver formed on the first exterior cover. An intake fan that introduces external air into the apparatus main body through a second louver formed in the exterior cover, and the second exterior cover has an opening through which a waste toner collection tank disposed inside the apparatus is exposed. The image forming apparatus according to claim 1, wherein the image forming apparatus is formed.