JP2006266630A - Cooling device and image forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent the rotation of a cooling fan when the cooling fan is retrorsely mounted. <P>SOLUTION: When the cooling fan 62 is retrorsely mounted to a casing 90, the rotation of the cooling fan 62 is prevented by a projecting part 96. The projecting part 96 is molded integrally with the casing 90. The cooling fan 62 comprises blades 64 rotatably supported to a frame 66, and the projecting part 96 abuts on the blade 64 of the cooling fan 62 in the retrorsely mounted state to prevent the rotation of the cooling fan 62. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a cooling device and an image forming apparatus.

  2. Description of the Related Art There are known a cooling apparatus and an image forming apparatus provided with a cooling fan for discharging heated air inside the apparatus to the outside of the apparatus. In this apparatus, the cooling fan is configured as a single component, and is generally used by being mounted on the casing of the apparatus during the manufacturing process (for example, Patent Document 1).

JP-A-10-161511

  However, in this apparatus, for example, when the apparatus is manufactured, the cooling fan may be mounted in a direction opposite to the original direction. In particular, the cooling fan and the structure of the housing to which the cooling fan is mounted can be used to generate an airflow in the direction of exhausting air from the inside of the apparatus or in a direction of generating an airflow in the direction of sucking air from the outside of the apparatus. In addition, when a configuration that can attach a cooling fan is adopted, it may be difficult to determine the direction of airflow unless the fan is actually driven, and there is a risk that the cooling fan will be installed in the opposite direction. large. If the cooling fan is installed in the opposite direction, the direction of the air flow generated by the cooling fan will also be reversed, and the heated air inside the device will be blown into the device without being discharged to the outside. Therefore, there is a problem that the apparatus may be damaged by heat.

Japanese Patent Application Laid-Open Publication No. 2004-259542 discloses a technique for attaching a member for preventing rotation of the cooling fan to the casing when the cooling fan is mounted in the reverse direction and preventing the reverse rotation of the cooling fan. . However, there is a problem that the number of parts may increase, leading to an increase in cost, and there is a concern that forgetting to attach a member that prevents reverse rotation.

SUMMARY OF THE INVENTION An object of the present invention is to provide a cooling device and an image forming apparatus that solve the above-mentioned conventional problems and reliably prevent the rotation when a cooling fan is mounted in the opposite direction.

In order to achieve the above object, the first feature of the present invention is that a housing, a cooling fan attached to the housing, and the cooling fan attached to the housing in the opposite direction. And a rotation preventing means for preventing rotation of the cooling fan. Therefore, when the cooling fan is mounted in the reverse direction, the cooling fan is prevented from rotating.

  Preferably, a part of the housing forms the rotation preventing means. Therefore, it is possible to avoid forgetting to attach the rotation prevention means during the manufacturing process, and the reverse rotation of the cooling fan is reliably prevented.

  In order to achieve the above object, the second feature of the present invention is that it has a casing and a cooling fan that can be mounted on the casing in the forward and reverse directions. And a frame having a reverse mounting surface, and a blade rotatably supported by the frame, the reverse mounting surface of the frame being more than a first distance from the front mounting surface of the frame to one end of the blade. The second distance from the other end of the blade to the other end of the blade is set short, and the protrusion protrudes into the cooling fan that is smaller than the first distance and larger than the second distance in the casing. It is in the cooling device provided. Therefore, when the cooling fan is mounted in such a direction that the front mounting surface side faces the casing, the blades can be rotated without contacting the protruding portion. On the other hand, when the cooling fan is mounted with its reverse mounting surface facing the housing, the blades are in a state where they cannot rotate by contacting the protruding member, and reverse rotation of the cooling fan is prevented.

  Preferably, a plurality of through holes penetrating from the front mounting surface to the reverse mounting surface provided in the cooling fan, a mounting portion provided at a position corresponding to the through hole of the housing, and the through hole And a plurality of through holes arranged symmetrically with respect to the cooling fan. Therefore, the cooling fan is inserted into the through hole and attached to the housing by the attachment member that reaches the attachment portion.

In order to achieve the above object, a third feature of the present invention includes an image forming apparatus main body,
A cooling fan that can be mounted on the image forming apparatus in the forward and reverse direction, and the cooling fan includes a frame having a normal mounting surface and a reverse mounting surface, and blades rotatably supported by the frame. The second distance from the reverse mounting surface of the frame to the other end of the blade is set shorter than the first distance from the front mounting surface of the frame to one end of the blade, and the image forming apparatus main body The image forming apparatus further includes a protrusion that protrudes into the cooling fan that is smaller than the first distance and larger than the second distance. Therefore, when the cooling fan is mounted in such a direction that the front mounting surface side faces the main body of the image forming apparatus, the blades can be rotated without contacting the protruding portion. On the other hand, when the cooling fan is mounted in such a direction that the reverse mounting surface faces the image forming apparatus main body, the blades are in a state where they cannot rotate by contacting the protruding member, and the reverse rotation of the cooling fan is prevented.

  Preferably, the cooling fan is provided in the vicinity of an optical writing device arranged in the image forming apparatus main body. Therefore, the heat generated from the optical writing device is discharged well out of the image forming apparatus by the cooling fan.

  Preferably, the cooling fan is provided in the vicinity of a control board disposed in the image forming apparatus main body. Therefore, the control board which is easily affected by heat is cooled well by the cooling fan.

  According to the present invention, there is provided a cooling device and an image forming apparatus capable of reliably preventing rotation of the cooling fan when the rotation preventing unit is not forgotten to be attached and the cooling fan is mounted in the opposite direction. .

Next, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows an outline of an image forming apparatus 10 according to an embodiment of the present invention. In FIG. 1, the image forming apparatus 10 has an image forming apparatus main body 12, and a cooling device 60 is attached to the image forming apparatus main body 12. The image forming means 14 and the control board 80 are provided in the image forming apparatus main body 12. And a discharge unit 16 is provided at the upper part of the image forming apparatus main body 12. For example, two stages of paper feeding units 18 and 18 are arranged at the lower part of the image forming apparatus main body 12.

  Each sheet feeding unit 18 has a sheet feeding cassette 20 and a sheet feeding roll 22 in which sheets are stored, and the sheets stacked on the sheet feeding cassette 20 are conveyed to the registration roll 24 by the rotation of the sheet feeding roll 22. Is done. Further, an image carrier 28 and a transfer device 36 of a process cartridge 46, which will be described later, are provided on the downstream side of the registration roll 24, and a fixing device 40 is further provided on the downstream side.

  Accordingly, the sheet fed from the sheet feeding cassette 20 of the sheet feeding unit 18 by the sheet feeding roll 22 is temporarily stopped by the registration roll 24 and passes between an image carrier 28 and a transfer device 36 described later at a timing. The developer image is transferred, and the transferred developer image is fixed by the fixing device 40 and discharged to the discharge unit 16 by the discharge roll 26.

  The image forming means 14 is of an electrophotographic system, and is charged by the image carrier 28 made of a photosensitive member, a charging device 30 made of, for example, a charging roll for uniformly charging the image carrier 28, and the charging device 30. An optical writing device 32 that writes a latent image on the image carrier 28 with light, a developing device 34 that visualizes the latent image of the image carrier 28 formed by the optical writing device 32 with a developer, and the developing device 34 A transfer device 36 composed of, for example, a transfer roll for transferring the developer image to the paper, a cleaning device 38 for cleaning the developer remaining on the image carrier 28, and the developer image on the paper transferred by the transfer device 36 on the paper. For example, a fixing device 40 including a pressure roll and a heating roll. The optical writing device 32 includes, for example, a scanning laser exposure device, and forms a latent image on the image carrier 28 across a process cartridge 46 described later. The cleaning device 38 includes a cleaning blade 42 that comes into contact with the image carrier 28 and a developer recovery unit 44 that stores the developer scraped off by the cleaning blade 42. The optical writing device 32 may use an LED or a surface emitting laser as another embodiment.

  In the process cartridge 46, the image carrier 28, the charging device 30, the developing device 34, and the cleaning device 38 are integrated, and these can be replaced as a unit. A control board 80 is provided below the optical writing means 32 described above.

  FIG. 2 is a cross-sectional view showing the details of the cooling device 60 described above, and shows a state in which the cooling fan 62 is attached in a correct orientation to a casing 90 that forms a part of the image forming apparatus main body 12, for example, a front cover. Show. The cooling device 60 is placed in the vicinity of the optical writing device 32 and the control board 80 in a state of being attached to the housing 90 (see FIG. 1).

The cooling fan 62 includes at least one blade 64 and a frame 66 that rotatably supports the blade 64. The frame 66 includes a main body side frame 68 positioned on the inner side of the apparatus when the cooling fan 62 is mounted in a correct orientation, a housing side frame 70 positioned on the opposite side of the main body side frame 68 and the blades 64, and A connecting frame 72 that connects the main body side frame 68 and the housing side frame 70 is provided. And this housing | frame side frame 70 comprises the regular attachment surface which is a surface which opposes the housing | casing 90, when a cooling fan is mounted | worn with the correct orientation. Further, the main body side frame 68 constitutes a reverse mounting surface that is a surface facing the housing 90 when the cooling fan is mounted in a direction opposite to the correct direction.

  The blades 64 supported by the frame 66 are rotated by a driving source such as a motor to generate an air flow from the inside of the apparatus main body to the housing 90 side. The blades 64 are not located at an equal distance from the main body side frame 68 and the casing side frame 70 but are disposed in the frame 66 at a location close to the main body side cover 68, and the main body side frame 68 constitutes the blades 64. The distance A is the distance B when the distance from the reverse mounting surface to one end of the blade is A and the distance from the normal mounting surface formed by the housing side frame 70 to the other end of the blade 64 is B. Is set shorter.

A part of the casing 90 to which the cooling fan 62 is attached protrudes in the direction of the cooling fan 62, and the protruding part forms a protruding part 96. The protrusion 96 is manufactured as a separate part from the casing 90 and is not attached to the casing 90 after that, but is manufactured as an integral part of the casing 90 from the beginning, for example, by injection molding or the like.

When the cooling fan 62 is attached to the housing 90, a part or all of the protruding portion 96 is inserted into the cooling fan 62. The length of the protruding portion 96 is such that C is longer than the distance A from the main body side frame 68 to the blade 64 when the length of the portion of the protruding portion 96 inserted into the cooling fan 62 is C. The distance from the housing side frame 70 to the blades 64 is set to be shorter than B, that is, A <C <B. For this reason, when the cooling fan 62 is attached in the correct direction, the blades 64 do not contact the protruding member 96. On the other hand, when the cooling fan 62 is mounted in the opposite direction, that is, when the cooling fan 62 is mounted in the direction in which the body side frame 68 faces the housing 90, the projecting portion 96 contacts the blade 64. The rotation of 64 is blocked.

FIG. 3 is a cross-sectional view showing details of the cooling device 60 described above, and shows a state in which the cooling fan 62 is attached to the housing 90 in a direction opposite to the correct direction. As described above, when the cooling fan 62 is mounted in the reverse direction, the length C of the portion of the protrusion 96 that is inserted into the cooling fan 62 is longer than the distance A from the main body side frame 68 to the blades 64, The portion 96 contacts the blade 64 and prevents the blade 64 from rotating.

FIG. 4 is a perspective view showing the details of the cooling fan 62 described above, and showing the cooling fan 62 from the image forming apparatus 12 side. In FIG. 4, the blade 64 described above rotates in the direction of the arrow in the drawing to generate an airflow in a direction from the apparatus main body side frame 68 to the housing side frame 70. The above-mentioned frame 66 is provided with, for example, a plurality of through holes 74 penetrating from the main body side frame 68 to the housing side frame 70. An attachment member 76 made of, for example, a screw is inserted into, for example, two of the four through holes 74 from the main body side frame 68 side, and a distal end portion of the attachment member 76 is provided in the housing 90. For example, the cooling fan 62 is attached to an attachment portion that is not shown in the figure, and is fixed to an attachment portion including a screw hole.

The plurality of through holes 74 are arranged symmetrically with respect to the cooling fan 62. For this reason, even when the cooling fan 62 is to be mounted in the reverse direction, mounting portions corresponding to the through holes 74 are present on the housing 90. As described above, in this embodiment, both the correct direction for generating the airflow in the direction of discharging air from the inside of the image forming apparatus and the direction for generating the airflow in the reverse direction of sucking air from the outside of the image forming apparatus are used. The cooling fan 62 can be attached to the housing 90.

The main body side frame 68 of the cooling fan 62 has a shape that supports the blades 64 without being obstructed. For this reason, the airflow generated by the blades 64 passes through the cooling fan 62 without being blocked by the main body side frame 68. Moreover, since it is such a shape, when the cooling fan 62 is mounted in the reverse direction, the protruding member 96 abuts against the blades 64 without obstruction.

FIG. 5 is a perspective view showing details of the cooling fan 62 described above, and showing the cooling fan 62 from the image housing 90 side. In FIG. 5, the blades 64 rotate in the direction of the arrow in the figure to generate an airflow in a direction from the apparatus main body side frame 68 to the housing side frame 70. The housing-side frame 70 of the cooling fan 62 only supports the rotation shaft of the blades 64 by, for example, four rotation shaft support portions 70 a, and nothing else blocks the blades 64. For this reason, the airflow generated by the blades 64 passes through the cooling fan 62 without being blocked by the housing-side frame 70.

FIG. 6 shows details of the above-described housing 90 made of, for example, a front cover. FIG. 6A is a perspective view showing the housing 90 from the inside of the image forming apparatus, and FIG. It is an enlarged view which shows the principal part of (a). 6, the housing 90 includes a mounting portion 92 to which the above-described cooling fan 62 is mounted, a vent hole 94 provided at a position facing the mounted cooling fan 62, and the above-described protrusion 96. .
As described above, the cooling fan 62 is mounted on the mounting portion 92 by the mounting member 76 (see FIG. 4). At a position facing the mounted cooling fan 62, for example, a vent hole 94 made of a plurality of slits is provided, and the air flow generated by the rotation of the blade 64 passes through the vent hole 94. A sufficient number of the vent holes 94 are provided so that a good air flow can be passed.

Next, the operation of the above embodiment will be described. The image carrier 28 is uniformly charged by the charging device 30, and the charged image carrier 28 is irradiated with light emitted from the optical writing device 32 based on the image signal to form a latent image. Light from the optical writing device 32 passes through the process cartridge 46. The latent image of the image carrier 28 formed by the optical writing device 32 is visualized by the toner of the developing device 34.

On the other hand, one of the paper feeding units 18 is selected by a size signal or the like, and the sheet stored in one of the paper feeding cassettes 20 is fed out by the feeding roll 22 and temporarily stopped by the registration roll 24, and the transfer device is timed. 36 and the image carrier 28.

When the sheet is guided between the transfer device 36 and the image carrier 28 in this way, the developer on the image carrier 28 is transferred to the sheet by the transfer device 36. The sheet onto which the developer has been transferred passes through the fixing device 40 and is discharged to the discharge unit 16.

In such an image forming process, heat is generated from, for example, a heater provided in the fixing device 40 or a motor provided in the optical writing device 32. This heat is discharged to the outside of the image forming apparatus by rotating the blades 64 of the cooling fan 62. When the cooling fan 62 is attached to the housing 90 in a normal direction, the rotation of the blades 64 generates an airflow in a direction in which the heated air in the image forming apparatus is discharged out of the image forming apparatus.

  Here, the state in which the cooling fan 62 is attached in the normal direction is the state shown in FIG. 2 described above, and the housing side frame 70 of the cooling fan 62 faces the housing 90 in a direction facing the housing 90 side. It means being attached. In this case, since the distance B from the housing side frame 70 to the blade 64 is longer than the length C of the portion of the protrusion 96 that is inserted into the cooling fan 62, the protrusion 96 does not contact the blade 64 and the blade 64. Rotates normally.

On the other hand, when the cooling fan 62 is attached to the housing 90 in the reverse direction, the projecting portion 96 comes into contact with the blades 64 to prevent the cooling fan 62 from rotating. Here, the state of being attached in the reverse direction is the state shown in FIG. 3 described above, and means a state in which the main body side frame 68 is attached in a direction facing the housing 90 side. In this case, since the distance A from the main body side frame 68 to the blade 64 is shorter than the length C of the portion of the protrusion 96 inserted into the cooling fan 62, the protrusion 96 comes into contact with the blade 64, The blade 64 is prevented from rotating.

Since the cooling fan 62 is prevented from rotating as described above, it is possible to generate an airflow in a direction opposite to the direction to be generated and to blow the heated air into the apparatus forming apparatus main body 12. Is prevented. In addition, when the rotation of the blades 64 is prevented even though the image forming apparatus 10 is in an operating state, a signal called a lock signal is output. The control board 80 can detect the stop of the cooling fan 62 by this signal. The control board 80 that detects the stop of the cooling fan 62 stops the operation of the apparatus and displays an error message such as “cooling fan stop” on a display unit (not shown).

  Moreover, in this embodiment, the part which protruded from the housing | casing 90 comprises the protrusion part 96, and the housing | casing 90 and the protrusion part 96 are shape | molded as integral. Therefore, unlike the case in which the protruding portion 96 is configured as a separate part from the housing 90 and is mounted on the apparatus during the manufacturing process or the like, the forgetting to mount the protruding portion 96 is prevented. As a result, when the cooling fan 62 is mounted in the opposite direction, the rotation of the cooling fan 62 is reliably prevented, and the image forming apparatus 10 is less likely to be damaged due to heat.

  As described above, the present invention can be used for a cooling apparatus and an image forming apparatus that discharge heated air inside the apparatus to the outside of the apparatus.

1 is a cross-sectional view illustrating an image forming apparatus according to an embodiment of the present invention. It is sectional drawing which shows the cooling device which concerns on embodiment of this invention, and shows the state with which the cooling fan was mounted | worn with normal orientation. It is sectional drawing which shows the cooling device which concerns on embodiment of this invention, and shows the state with which the cooling fan was mounted | worn in the direction opposite to normal direction. It is a perspective view which shows the cooling fan which concerns on embodiment of this invention. It is a perspective view which shows the cooling fan which concerns on embodiment of this invention. It is a perspective view which shows the housing | casing which concerns on embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Image forming apparatus 12 Image forming apparatus main body 14 Image forming means 28 Image carrier 30 Charging device 32 Optical writing device 34 Developing device 36 Transfer device 38 Cleaning device 40 Fixing device 46 Process cartridge 60 Cooling device 62 Cooling fan 64 Blade 66 Frame 68 Body side frame 70 Case side frame 72 Connection frame 74 Through hole 76 Mounting member 80 Control board 90 Case 92 Mounting part 94 Ventilation part 96 Projection part

Claims (7)

A housing,
A cooling fan attached to the housing;
And a rotation preventing means for preventing rotation of the cooling fan when the cooling fan is attached to the casing in the opposite direction. The cooling device according to claim 1, wherein a part of the casing serves as the rotation preventing means. A housing,
It has a cooling fan that can be attached to the case in the forward and reverse direction,
The cooling fan includes a frame having a normal mounting surface and a reverse mounting surface, and blades rotatably supported by the frame,
The second distance from the reverse mounting surface of the frame to the other end of the blade is set shorter than the first distance from the front mounting surface of the frame to one end of the blade,
The cooling device according to claim 1, wherein the housing is provided with a protrusion that protrudes into the cooling fan that is smaller than the first distance and larger than the second distance. A plurality of through holes penetrating from the normal mounting surface to the reverse mounting surface provided in the cooling fan;
A mounting portion provided at a position corresponding to the through hole of the housing;
An attachment member inserted into the through hole and reaching the positioning portion;
The cooling device according to claim 3, wherein the plurality of through holes are symmetrically disposed on the cooling fan. An image forming apparatus main body;
A cooling fan that can be mounted on the image forming apparatus main body in the forward and reverse directions;
The cooling fan includes a frame having a normal mounting surface and a reverse mounting surface, and blades rotatably supported by the frame,
The second distance from the reverse mounting surface of the frame to the other end of the blade is set shorter than the first distance from the front mounting surface of the frame to one end of the blade,
An image forming apparatus, wherein the image forming apparatus main body is provided with a protrusion that protrudes into the cooling fan that is smaller than the first distance and larger than the second distance. 6. The image forming apparatus according to claim 5, wherein the cooling fan is provided in the vicinity of an optical writing device disposed in the image forming apparatus main body. The image forming apparatus, wherein the cooling fan is provided in the vicinity of a control board disposed in the main body of the image forming apparatus.

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