JPH11153939A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively use an existing equipment without limiting arrangement constitution of existing parts and to simply cool an electric parts requiring thermal measures by providing an opening of a duct on the position of the duct opposite to the electric parts. SOLUTION: The opening 6 for cooling a power source unit 5 is opened/ arranged on a side surface of an exhaust duct 44 in an intake device 4 opposite to the power source unit 5. On the power source unit 5 side, when intake operation by this intake device 4 is performed, a part of air flowing through the exhaust duct 44 toward the device outside flows out from the opening 6 as shown by the arrow E of a chain line to be sent to the power source 5 side. Thus, the power source unit 5 is cooled (air cooled) simply by air flowing out from the exhaust duct 44. Then, the need of cooling the power source unit 5 by setting up an exclusive cooling fan is eliminated. Further, at this time, the need of changing the setting place of the existing parts such as the electric parts and the duct, is eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as a copier or a printer having an electric component such as a power supply device and an electronic circuit board which requires a countermeasure against heat, and particularly to a new countermeasure for cooling the electric component. The present invention relates to an image forming apparatus that has been applied.

[0002]

2. Description of the Related Art In an image forming apparatus such as a copying machine or a printer using an electrophotographic system, a motor,
2. Description of the Related Art Electric components such as a power supply device for supplying electricity to electric devices such as a discharge component and a heating component, and a control circuit board for controlling the operation of the electric devices are used. Some of these electric components are heated when the temperature of the electric component itself or its surrounding environment rises due to the heat generated from the component itself or the heat generated from other heat-generating components, and the temperature exceeds a predetermined temperature. Include electrical components that are vulnerable to high heat, such as elements that make up the electrical components being damaged or malfunctioning due to the high heat.

[0003] Such electrical components having relatively low durability against heat require measures against the heat. That is, if the countermeasure against the heat is neglected, the image forming apparatus itself may not operate normally or the image quality may be deteriorated, so that the image forming apparatus itself lacks reliability. For this reason, conventionally, an image forming apparatus has been proposed in which this type of electric component is provided with a measure against heat.

For example, in Japanese Patent Application Laid-Open No. Hei 4-240864, a power supply unit containing main power supply parts is housed under image transfer means, and a through hole is provided near the paper supply means of the power supply unit and on the fixing device side. Is provided to allow air to flow through the power supply unit, so that the air flows from the paper feeding means side to the fixing device side via the power supply unit by using the chimney effect without using a cooling fan. An image forming apparatus is shown in which the power supply unit is cooled by the generated airflow.

Japanese Patent Laid-Open Publication No. Hei 4-24167 discloses a power supply device installed in a main body of a device, in which a heat radiation wall is provided.
By arranging the heat radiating wall at a predetermined interval to face the outer cover, and forming a paper transport path by the ribs provided on the outer cover and the heat radiating wall, it is possible to use a dedicated fan without using a dedicated fan. An image forming apparatus that radiates and cools a power supply device is shown.

[0006]

However, each of the above-mentioned prior arts has the following problems. First, in the former case, in order to obtain the chimney effect, the power supply unit is installed between the high-temperature section (fixing unit) and the low-temperature section (paper supply unit). The components must be arranged so that the amount of heat generated gradually increases, which greatly restricts the arrangement of other components such as the power supply unit.

In the latter case, it is necessary to dispose the power supply in the vicinity of the paper transport path, which also places great restrictions on the arrangement of some of the components.

The present invention has been made in view of the above-mentioned problems of the prior art, and an object of the present invention is to effectively use existing equipment without restricting the arrangement of existing parts. It is an object of the present invention to provide an image forming apparatus capable of easily cooling an electric component requiring a heat countermeasure.

[0009]

According to the image forming apparatus of the present invention which can achieve the above object, air taken in by a suction fan from predetermined parts provided in the apparatus main body is guided to the outside of the apparatus and discharged. In an image forming apparatus having a duct disposed in the apparatus main body and an electric component which needs to be protected from heat and is installed in the apparatus main body around the duct, in a portion opposed to the electric part of the duct, An opening is provided so that a part of the air before being discharged to the outside of the apparatus through the duct flows out toward the electric component.

According to this image forming apparatus, a part of the air before being discharged to the outside of the apparatus through the duct flows out from the opening provided in the duct toward the electric component and is sent. Electrical components that require thermal measures are cooled. Further, there is no need to change the installation location of the existing components such as the electric components and the duct.

In this image forming apparatus, it is preferable to provide an exhaust port at a portion of the apparatus main body near the electric component.

In this case, the air sent from the opening of the duct to the electric component side is discharged to the outside of the device from the exhaust port provided in the device main body after passing through the electric component. As a result, the air does not stay around the electric components or inside the apparatus main body, and does not generate unintended turbulent airflow. In addition, unnecessary heat is discharged to the outside of the apparatus together with the air, and the electric components are efficiently cooled.

Further, in each of such image forming apparatuses, a member for forming an air flow path through which air flows by being guided from the duct toward the electric component may be provided between the duct and the electric component. preferable.

In this case, the air flowing from the opening of the duct toward the electric component is more reliably sent to the electric component. This ensures that the electrical components are cooled.

[0015]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

First Embodiment FIGS. 1 to 3 show a copying machine according to an embodiment of the present invention. FIG. 1 is a schematic diagram showing a configuration on the front side, and FIG. FIG. 3 is a schematic cross-sectional view taken along line AA of FIGS. 1 and 2.

In FIG. 1, reference numeral 1 denotes a main body of an image forming apparatus, and a document reading section 2 and an image forming section 3 are mainly disposed on the front side inside the apparatus main body 1. The document reading unit 2 illuminates a document (not shown) placed on a document placing table (platen) 20 with an illumination lamp 21, and reflects the reflected light of the illumination light reflected on the document surface by a reflecting mirror 22. The light is guided to a photosensitive belt, which will be described later, of the image forming unit 3 via an optical system such as a lens 23 and is exposed. A part of the illumination lamp 21 and a part of the reflection mirror 22 are moved in a certain direction below the document by a moving mechanism (not shown). Also,
Reference numeral 24 in the drawing denotes a platen cover, and reference numeral 25 denotes a partition member having a light shielding property.

The image forming section 3 first uniformly charges a photoreceptor belt 30 supported by a roll or the like (not shown) so as to rotate at a constant speed in the direction of arrow B by a corona discharge type charger 31. The original reading unit 2 exposes a light image based on image information of the original to form an electrostatic latent image, and then develops the electrostatic latent image with a developer supplied by a developing unit 32 to form a toner. Form an image. Next, the toner image formed on the photosensitive belt 30 is
Is electrostatically transferred by a corona discharge type transfer unit 35 onto a sheet P supplied from the printer via a sheet transport path 34, and on the other hand, the cleaning unit removes toner and the like remaining on the photoreceptor belt 30 after transfer. Remove by 36. After the transfer, the sheet P is conveyed by a roll-type heat fixing unit 38 by a suction type sheet conveying belt 37 to thermally fix the toner image, and then discharged outside the apparatus. This allows
Copying of the original is completed. Reference numeral 39 in FIG. 1 denotes a discharge roll, and 37a in FIG. 3 denotes a number of suction holes formed in the belt.

In this image forming apparatus, FIG.
As shown in FIG. 3 and FIG. 3, an air intake device 4 and a power supply unit 5 as an electrical component requiring thermal measures and mainly containing a power supply device and a power supply circuit are provided on the back side inside the device main body 1. Or is installed. Reference numeral 10 in FIG.
Is a rear frame disposed so as to separate a front space and a rear space of the apparatus main body 10.

The suction device 4 sucks and collects and removes ozone generated in the charging device 31 and the transfer device 35 in the image forming section 3, and sucks the paper in the paper transport belt 37 to make it adhere to the belt surface. And ozone collecting ducts 40 and 41 attached to be connected to the charger 31 and the transfer unit 35, respectively, and an adsorption duct 4 attached to be connected to the paper transport belt 37.
2, an intake duct 43 to which the ozone recovery ducts 40 and 41 and an adsorption duct 42 are connected, respectively, to take in air from the respective ducts, and a It is mainly composed of an exhaust duct 44 for guiding.

An intake duct 43 is connected at its upper part to ducts 40 and 41 for collecting ozone and a duct 42 for adsorption. And an ozone / dust filter 46 (in this example, provided upstream of the fan). The lower portion of the exhaust duct 44 is connected to an exhaust port (not shown) formed at the bottom of the main body 1 so that the air taken in is finally discharged to the outside of the apparatus main body 1.

On the other hand, the power supply unit 5
Is installed on the bottom frame 12 of the apparatus main body 1 near one side of the intake duct 43 and the exhaust duct 44. In addition,
In FIGS. 2 and 3, the power supply unit 5 is illustrated in the form of a sealed box for convenience, but the actual power supply unit 5 has an open structure that allows ventilation. From the power supply unit 5, predetermined electric power (electric power) is distributed and supplied to various electric devices in other components including the document reading unit 2, the image forming unit 3, and the suction device 4.

In this image forming apparatus, an opening 6 for cooling the power supply unit 5 is provided on a side of the exhaust duct 43 of the intake device 4 facing the power supply unit 5. The shape, size, opening position, and the like of the opening 6 are appropriately set so that part of the air before being discharged to the outside of the apparatus through the exhaust duct 43 flows toward the electric unit 5.

Next, the operation of the suction device and the cooling operation of the power supply unit in the image forming apparatus having such a configuration will be described.

First, the operation of the suction device 4 will be described. During the image forming operation, the suction fan 45 operates to generate a suction force in the suction duct 43, and the suction force is applied to the ozone collecting duct 40. , 41 and the suction duct 42 as appropriate. Thus, the ozone generated in the charger 31 and the transfer device 35 is sucked in through the ozone collecting ducts 40 and 41 together with the air. Further, the paper conveyance belt 37 is in a state of sucking the transferred paper P by the suction of the suction duct 42. The air sucked through the ozone recovery ducts 40 and 41 and the suction duct 42 is supplied to an air intake duct 43.
After passing through the ozone / dust filter 46, ozone and dust contained in the air are removed. The air from which ozone, dust and the like have been removed is discharged to the outside of the apparatus through an exhaust duct 44.

On the other hand, on the power supply unit 5 side, when the intake operation by the intake device 4 is performed, the exhaust duct 4
A part of the air flowing toward the outside of the apparatus through the inside of the opening 4 is indicated by an alternate long and short dash line arrow E in FIGS.
And is sent to the power supply unit 5 side. Thus, the power supply unit 5 is easily cooled (air cooled) by the air flowing out of the exhaust duct 44. Therefore, there is no need to install a dedicated cooling fan to cool the power supply unit 5. The exhaust duct 4 for cooling the power supply unit 5
Air sent from 4 is ozone / dust filter 4
6, it is harmless and clean, so that there is no problem even if it touches each element, component, etc. of the power supply unit 5.

In the first embodiment, FIG.
As an example, the exhaust port 7 may be opened in the side frame 13 of the apparatus main body 1 near the power supply unit 5 of the apparatus main body 1. When the exhaust port 7 is provided, the air sent from the exhaust duct 44 to the power supply unit 5 does not drift inside the apparatus main body 1 after passing through the power supply unit 5, and is discharged outside the apparatus through the exhaust port 7. Is done. Further, by discharging the air from the exhaust port 7, the air flowing from the exhaust duct 44 toward the power supply unit 5 flows more smoothly. The shape, size, opening position, and the like of the exhaust port 7 are appropriately set so that air containing heat after passing through the power supply unit 5 smoothly flows out of the apparatus.

Second Embodiment FIGS. 4 and 5 show an image forming apparatus according to another embodiment of the present invention. FIG. 4 is a schematic perspective view showing the structure on the back side of the image forming apparatus. FIG. 5 is a schematic sectional view taken along line CC of FIG. 4. The image forming apparatus according to the first embodiment except that members for forming air flow paths are additionally provided between the exhaust duct 44 and the power supply unit 5 and between the power supply unit 5 and the apparatus main body 1. It has the same configuration as the image forming apparatus.

That is, in this embodiment, a branch duct 47 is provided at the portion of the exhaust duct 44 provided with the opening 6 in the first embodiment so as to project toward the power supply unit 5. Further, an air guide plate 50 extending substantially horizontally from above the branch duct 47 to the power supply unit side is protruded from a portion of the power supply unit 5 facing the exhaust duct 44. Further, an air guide plate 51 connected to the uppermost opening on the side frame 13 side of the power supply unit 5 and the above-described exhaust port 7 is provided at a portion of the power supply unit 5 facing the device body side frame 13. I have. The shape and size of the branch duct 47 and the air guide plates 50 and 51 are arbitrary as long as air is guided and flowed by the duct and the guide plate.

The operation of the image forming apparatus according to the second embodiment is the same as that of the image forming apparatus according to the first embodiment. A cooling effect is obtained. In other words, on the power supply unit 5 side, when the suction operation is performed by the suction device 4, a part of the air flowing toward the outside of the device through the exhaust duct 44 is indicated by a chain line arrow E in FIGS. As described above, the branch duct 47 surely flows to the power supply unit side, and the air flowing from the branch duct 47 is guided by the air guide plate 50 so as to be reliably sent to the power supply unit 5. In addition, the air that has passed through the power supply unit 5 is guided by the air guide plate 51 so as to be regulated, and is reliably discharged to the outside of the apparatus (an arrow F indicated by a chain line). As a result, the power supply unit 5 is more reliably and efficiently cooled. For this reason, in this case, the installation and use of a dedicated fan for cooling the power supply unit 5 is further unnecessary.

In each of the above-described embodiments, the case where the present invention is applied to an analog type copying machine has been exemplified. However, the present invention is not limited to this type of copying machine, and other types of copying machines can be used. It goes without saying that the present invention can be similarly applied to a printer, a printer, a multifunction peripheral, or the like.

[0032]

As described above, according to the present invention,
An opening is provided in the part of the duct facing the electrical components so that part of the air before being discharged to the outside of the device through the duct flows out toward the electrical components. In addition, electric components requiring heat measures can be easily cooled by effectively utilizing existing facilities. At this time, there is no need to change the installation location of the existing components such as the electric components and the duct. As described above, since the power supply components can be cooled reliably, damage and malfunction of the electric components due to high heat do not occur, and as a result, more stable image quality and reliability of the device can be obtained.

In the case where an exhaust port is provided in a portion of the apparatus main body near the electric component, air sent from the opening of the duct to the electric component side is provided in the apparatus main body after passing through the electric component. Since the air is discharged from the exhaust port to the outside of the device, it is possible to prevent the air from staying around the electric parts and the inside of the device main body, or to generate an unintended turbulent airflow. Is discharged to the outside of the apparatus together with the air, so that the electric components can be cooled more efficiently.

Further, when a member is provided between the duct and the electric component to form an air flow path through which air is guided from the duct toward the electric component and flows, the air flows from the duct opening toward the electric component. Since the air flowing toward the electric component is more reliably sent to the electric component, the electric component can be cooled more reliably.

[Brief description of the drawings]

FIG. 1 is a schematic diagram illustrating a configuration of a front side of an image forming apparatus according to a first embodiment of the present invention.

FIG. 2 is a schematic perspective view showing a configuration on the back side of the image forming apparatus of FIG. 1;

FIG. 3 is a schematic sectional view taken along the line AA in FIGS. 1 and 2;

FIG. 4 is a schematic perspective view illustrating a configuration on a rear side of an image forming apparatus according to a second exemplary embodiment of the present invention.

FIG. 5 is a schematic sectional view taken along line CC of FIG. 4;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Device main body, 5 ... Power supply unit (Electrical component which needs a heat countermeasure), 6 ... Opening, 7 ... Exhaust port, 31 ... Charging device (Predetermined component), 35 ... Transfer device (Predetermined component), 37 ... Paper Conveying belt (predetermined parts), 44: exhaust duct, 45: intake fan, 47: branch duct (member forming air flow path), 50, 51: air guide member (same as above), E: flowing out of duct Air flow.

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[Procedure amendment]

[Submission date] December 4, 1997

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0023

[Correction method] Change

[Correction contents]

[0023] Then, in the image forming apparatus, on the side opposite to the power supply unit 5 of the exhaust duct 4 4 in the intake apparatus 4, the opening 6 for cooling the power supply unit 5 is opened. The shape of the opening 6, for dimensions and opened position and the like, part of the previous air is discharged to the outside of the apparatus is set appropriately flow out toward the electric unit 5 side through the exhaust duct 4 inside 4.

Claims (3)

[Claims] 1. A duct disposed in an apparatus main body so that air taken from a predetermined component disposed in the apparatus main body by an intake fan is guided to the outside of the apparatus and discharged therefrom, and a duct is provided around the duct. In an image forming apparatus having an electric component requiring heat countermeasures installed in an apparatus main body, a part of the air before being discharged to the outside of the apparatus through the duct is provided in a part of the duct facing the electric part. An image forming apparatus provided with an opening that flows toward a side. 2. The image forming apparatus according to claim 1, wherein an exhaust port is provided in a portion of the apparatus main body near the electric component. 3. The image forming apparatus according to claim 1, wherein a member is provided between the duct and the electric component, the member forming an air flow path through which air flows from the duct toward the electric component.