JP4286081B2 - Image forming apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention is used in a copying machine, a laser printer, a facsimile machine, and various office automation equipment. In particular, a casing containing an electronic board or a power source that generates heat is arranged vertically, and a single fan generates up-and-down airflow. The present invention relates to an image forming apparatus that generates and cools the inside of a casing.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, in OA equipment such as an image forming apparatus, various electronic devices, and the like, an electronic board, a power source, and the like on which a computer system for controlling and driving each actuator of the apparatus is housed in a housing. Each component and power supply mounted on such an electronic board generate heat due to continuous use, causing a temperature rise in the housing. This increase in temperature is very undesirable for maintaining the function stably. For this reason, conventionally, it has been generally performed to cool the entire device casing or directly cool the electronic substrate portion, the CPU element, and the like.
[0003]
Also, an image forming apparatus is known that reduces the number of fans and noise by sharing a fan for intake and exhaust and confining the fan inside a casing (see, for example, Patent Document 1). That is, here, even in an image forming apparatus such as a copying machine or a laser printer using an electrophotographic process, a cooling fan is provided to stabilize the image quality by suppressing the temperature rise in the machine or to generate in the machine gas. The gas concentration is diluted.
[0004]
As described above, in each of the conventional devices, the housing containing the electronic board or the power source that generates heat is provided with an intake and exhaust fan for each housing, and has an independent cooling structure. In this case, since each fan is necessary, the number of fans increases as a whole. In recent years, with the increase in speed and performance of equipment, the electrical system of the equipment has been heated, and the electrical system has been forced to be space-saving and high-density due to the downsizing of the equipment.
[0005]
FIG. 8 shows a conventional configuration, in which cooling fans 110 and 111 are individually arranged in the upper and lower electrical housings to take individual cooling structures. Conventionally, it is difficult to secure a place for installing the cooling fan, and as shown in FIG. 8, the electrical housings are called the upper electrical housing 100a and the lower electrical housing 100b for the functional reasons of the equipment. The structure is taken. When the casings are lined up and down in this way, the exhaust fan 110 is provided in the upper electrical casing 100a, and the intake fan 111 is provided in the lower electrical casing 100b.
[0006]
[Patent Document 1]
Japanese Patent Laid-Open No. 2002-169450
[Problems to be solved by the invention]
However, as described above, in the conventional cooling structure, in the case of the configuration shown in FIG. Further, when the location of the exhaust fan mounting portion of the upper electrical housing becomes a height close to a human ear, noise due to the rotation of the fan will be a concern. On the other hand, if the intake fan of the lower electrical housing is at a lower position close to the floor, dust on the floor is drawn into the housing (apparatus), causing equipment damage. Further, in the image forming apparatus described in Patent Document 1, since the heat of the intake air becomes high, it is not effective for a heating element having a large heat dissipation amount.
[0008]
Also, as in Patent Document 1, there has been proposed a method for reducing the number of fans and noise by sharing a fan for intake and exhaust and confining the fan inside the casing. Since the heat of the intake air becomes higher than the case where the heat is not generated, such a method cannot be applied to a heating element having a large heat radiation amount.
[0009]
The present invention has been made in view of the above, and in an image forming apparatus divided into upper and lower parts, eliminates annoyingness and dust suction caused by fan rotation, and realizes an efficient cooling structure with a minimum number of fans. The purpose is to do.
[0010]
[Means for Solving the Problems]
In order to achieve the above object, the image forming apparatus according to claim 1 is divided into upper and lower electrical housings and upper and lower electrical housings, and each housing is an electrical component serving as a member to be cooled. In the image forming apparatus, the lower electrical housing and the upper electrical housing are connected to form an integrated structure, and an air flow path that passes substantially vertically from the lower electrical housing to the upper electrical housing is provided. A vent hole for forming an air flow into each of the lower surfaces of the lower and upper electrical housings, an exhaust hole provided on the upper surface of the upper electrical housing, and the lower electrical housing The fan is disposed on the upper side of the fan, and the casing forms negative pressure with respect to the outside by generating an air current. The electrical component of the upper electrical casing is disposed on one side, and the electrical component is disposed. A partition plate that forms a duct function on the opposite side of the surface; Wherein the electrical component is arranged to be parallel to the airflow so as to reduce the pressure loss, the partition plate is made of emissivity of 80% or more of the radiating steel or aluminum.
[0011]
According to this invention, using the chimney effect and Bernoulli's theorem, an air flow path is formed through the lower electrical housing and the upper electrical housing as an integral structure and extending substantially vertically from the lower electrical housing to the upper electrical housing. A ventilation hole for taking in airflow into each lower surface of the lower and upper electrical housings, an exhaust hole provided on the upper surface of the upper electrical housing, and an upper portion of the lower electrical housing, The fan in which the casing forms a negative pressure with respect to the outside and the electrical components of the upper electrical casing are arranged on one side, and the duct function is provided on the side opposite to the plane on which the electrical components are placed. And a partition plate to be formed, and further arranged to be parallel to the air flow so as to reduce the pressure loss, and the partition plate is made of a heat radiating steel plate or aluminum having an emissivity of 80% or more, By generating up and down airflow, It is possible to reduce the number of fans to a minimum, and it is possible to prevent the fans installed in the conventional lower electrical housing from sucking dust from the floor and the upper electrical housing. It is possible to reduce the noise caused by the fan installed on the body. In addition, it is effective to install a fan on the upper part of the lower electrical housing, exhaust the airflow from the exhaust port of the lower electrical housing, and draw outside air from the intake port of the upper electrical housing. A simple air flow can be generated in the housing. In addition, a duct member serving as an air flow path is formed by arranging partition members inside the lower electrical housing and the upper electrical housing, and the air flow generated by the fan and the throttle shape is released outside the machine by this duct function. It becomes possible to guide.
[0020]
In the image forming apparatus according to claim 2 , heat pipes are arranged in specific heat generating portions in the lower electrical casing and the upper electrical casing.
[0021]
According to the present invention, by providing a heat pipe in a specific heat generation portion in the lower electrical casing and the upper electrical casing, cooling can be performed individually without adding a fan to a location where the temperature rises within the casing. It becomes possible to do.
[0022]
The image forming apparatus according to claim 3 further includes a ventilation hole for taking in heat from the lower electrical component casing and the heating element adjacent to the upper electrical component casing.
[0023]
According to the present invention, by providing the ventilation hole that takes in the heat from the heating element adjacent to the lower electrical casing and the upper electrical casing, the heat from the heating element adjacent to the casing can be taken in and exhausted. It becomes possible.
[0024]
DETAILED DESCRIPTION OF THE INVENTION
DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, a preferred embodiment of an image forming apparatus according to the invention will be described in detail with reference to the accompanying drawings. The present invention is not limited to this embodiment.
[0025]
The present invention uses the chimney effect and Bernoulli's theorem to reduce the number of cooling fans in each of the housings containing the electronic boards and power supplies with heat generation arranged above and below, and to minimize the airflow generated by the fans. By adopting a structure that effectively guides and exhausts air outside the machine, the heat dissipation efficiency of the heating element is improved and suction of harsh noise and dust is avoided. This will be specifically described below.
[0026]
FIG. 1 is a perspective view showing an example of an image forming apparatus having a configuration in which electrical housings according to an embodiment of the present invention are arranged vertically. In other words, this image forming apparatus has a component structure that is divided into upper and lower parts, and each has an electrical housing on one side. In addition, the two electrical housings are configured so that at least the airflow path is connected vertically as described later.
[0027]
FIG. 2 is a front view of the electrical housing. In the conventional configuration shown above (see FIG. 8), the upper and lower electrical housings have cooling fans 110 and 111, respectively, and have an individual cooling structure. On the other hand, in this embodiment, as shown in FIG. 2, the fan 110 of the upper electrical housing in FIG. 8 shown above is eliminated, and the blowing fan 111 installed at the lower portion of the lower electrical housing. Is arranged at the upper part of the lower electrical housing, and the electrical cooling fan 5 shared by the upper and lower electrical housings is configured. As this electrical cooling fan 5, for example, an axial fan with a compact and large air volume is used.
[0028]
Further, as an air flow path generated by the electrical cooling fan 5, the upper electrical housing 1 and the lower electrical housing 2 are connected to form an integrated structure. For this reason, a large chimney effect is produced in combination with the upper and lower housings. A ventilation hole 6 for taking in outside air is provided in the outer wall of the lower housing of the upper electrical housing 1. As a result, the lower part of the upper electrical housing 1 becomes negative pressure with respect to the outside of the electrical housing due to the above-described chimney effect and the fan airflow once throttled at the upper part of the lower electrical housing 2. It is configured to be able to capture.
[0029]
At this time, the lower surfaces of the upper and lower casings are provided with ventilation holes for taking in the airflow from the electrical cooling fan 5, as indicated by reference numerals 7 and 8 in FIG. Further, an exhaust hole 9 is provided on the upper surface of the upper electrical housing 1. Also, the electronic boards and power supplies housed in the upper electrical housing 1 and the lower electrical housing 2 are arranged so as to be parallel to the air current as shown by reference numeral 10 in FIG. 3 so as to reduce pressure loss. Has been. That is, in order not to obstruct the airflow as much as possible, electronic components and the like are arranged in parallel along the airflow so as to increase the cooling efficiency for the place where the electrical components are arranged.
[0030]
FIG. 4 is an explanatory diagram showing a configuration in which a partition plate 13 for providing the duct 12 is arranged inside the electrical housing. That is, the duct function is provided by the arrangement of the partition plate 13. By providing this duct 12, it is possible to cool the electrical component 14 arranged on the partition plate in the component mounting space 11 not only from the component surface but also from heat radiation from the partition plate 13. The cooling efficiency with respect to the place where the components are arranged can be increased.
[0031]
Further, in this embodiment, the partition plate 13 shown in FIG. 4 is made of a heat radiating steel plate having an emissivity of 80% or more or a material having a high heat radiating property such as aluminum, so that the electrical component housed in the component mounting space 11 It is easy to conduct heat to the duct 12. Thereby, the thermal radiation efficiency of the heat which an electrical equipment component emits can be raised. In the case of an aluminum material, a heat dissipation effect can be further expected by adopting a structure that increases the surface area like a heat sink.
[0032]
FIG. 6 shows an example of a configuration in which some high heat elements, components 15 and the like in the two upper and lower electrical housings are individually cooled by the heat pipe 16. With such a configuration, in addition to the cooling of the entire inside of the casing described above, it is possible to individually cool the individual high-heat locations by the electrical cooling fan 5. The heat pipe is a closed-loop heat transfer element that uses latent heat of liquid evaporation and condensation, and is generally used as a device that can transport a large amount of heat with a small temperature difference.
[0033]
FIG. 7 shows an example in which a ventilation port 18 for taking in heat from a heating element 17 such as a main motor for driving a photoconductor on the main body side is formed in the upper electrical housing 1. A ventilation hole 1 and the like are provided in the duct outer wall surface 19 of the electrical housing, heat from the heating element 17 such as a main motor is taken into the duct 12 and exhausted by the electrical cooling fan 5. As a result, an effective heat radiation effect can be obtained in a highly heat-generating part such as a motor among electrical parts.
[0034]
In this embodiment, the image forming apparatus has been described as an example. However, the present invention can be similarly applied to other OA devices and electronic devices in which a heating element such as an electrical component is disposed in the housing.
[0035]
【The invention's effect】
As described above, according to the image forming apparatus (Claim 1) of the present invention, the lower electrical component and the upper electrical component casing are integrally formed using the chimney effect and Bernoulli's theorem. An air flow path that passes through the casing from the casing to the upper electrical casing substantially vertically is provided, and a ventilation hole for taking in the airflow into each of the lower surfaces of the lower and upper electrical casings, and an exhaust provided on the upper surface of the upper electrical casing. The fan is placed on the upper side of the lower electrical housing, and the fan forms a negative pressure against the outside by generating an air flow, and the electrical components of the upper electrical housing are placed on one side. A partition plate that forms a duct function on the side opposite to the surface on which the electrical component is disposed, and further, the electrical component is disposed so as to be parallel to the air flow so as to reduce pressure loss, and the partition plate is Made of heat-dissipating steel plate or aluminum with an emissivity of 80% or more. In the image forming apparatus is divided vertically by, it is possible to eliminate the jarring caused by rotation of the fan, also can eliminate the suction of dust from the floor, and efficient cooling structure with minimal fan Is realized. In addition, it is effective to install a fan on the upper part of the lower electrical housing, exhaust the airflow from the exhaust port of the lower electrical housing, and draw outside air from the intake port of the upper electrical housing. A simple air flow can be generated in the housing. In addition, a duct structure serving as an air flow path is formed by arranging partition members inside the lower electrical housing and the upper electrical housing, and the air flow generated by the fan and throttle shape is released outside the machine by this duct function. Can lead.
[0040]
Further, according to the image forming apparatus of the present invention (Claim 2 ), since the heat pipe is provided in a specific heat generation portion in the lower electrical casing and the upper electrical casing, a motor having a high temperature rise in the casing, etc. It is not necessary to provide a fan for each location, and cooling can be performed individually without adding a fan.
[0041]
In addition, according to the image forming apparatus of the present invention (Claim 3 ), the ventilation holes for taking in heat from the heating elements adjacent to the lower electrical casing and the upper electrical casing are provided. Heat from the heating element can be easily taken in and exhausted.
[Brief description of the drawings]
FIG. 1 is a perspective view illustrating an example of an image forming apparatus having a configuration in which electrical housings according to an embodiment of the present invention are arranged vertically.
FIG. 2 is an explanatory view of the electrical housing of FIG. 1 as viewed from the front.
FIG. 3 is an explanatory diagram showing a component arrangement direction inside the electrical housing according to the embodiment of the present invention.
FIG. 4 is an explanatory diagram showing a configuration in which a partition plate for providing a duct is arranged inside the electrical housing according to the embodiment of the present invention.
FIG. 5 is an explanatory diagram showing air flow directions of components and duct portions inside the electrical housing according to the embodiment of the present invention.
FIG. 6 is an explanatory diagram showing a configuration example in which some high heat elements, components, and the like are individually cooled by a heat pipe in the electrical housing according to the embodiment of the present invention.
FIG. 7 is an explanatory diagram showing an example in which a ventilation port for taking in heat from a heating element such as a motor on the main body side is formed in the upper electrical housing according to the embodiment of the present invention.
FIG. 8 is an explanatory diagram illustrating an arrangement example of cooling fans of a conventional image forming apparatus.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Upper electrical component housing | casing 2 Lower electrical component housing | casing 5 Electrical cooling fan 6 Ventilation holes 7, 8 Ventilation holes 9 Ventilation holes 11 Component mounting space 12 Duct 13 Partition plate 14 Electrical component 16 Heat sink 17 Heating element 18 Ventilation port 19 Duct Outer wall

Claims (3)

In the image forming apparatus in which the upper and lower electrical housings are divided into upper and lower electrical housings and electrical components that are to be cooled are mounted on the respective housings,
The lower electrical component housing and the upper electrical component housing are connected to form an integrated structure, and form an air flow path that extends substantially vertically from the lower electrical component housing to the upper electrical component housing,
Ventilation holes for taking airflow into the lower surfaces of the lower and upper electrical housings, respectively,
An exhaust hole provided on the upper surface of the upper electrical housing;
A fan that is disposed at the top of the lower electrical housing and generates negative airflow to the outside by generating an airflow;
An electrical component of the upper electrical casing is disposed on one side, and a partition plate that forms a duct function on the side opposite to the surface on which the electrical component is disposed,
With
The electrical component is arranged so as to be parallel to the air flow so as to reduce pressure loss,
The image forming apparatus , wherein the partition plate is made of a heat radiating steel plate or aluminum having an emissivity of 80% or more . The image forming apparatus according to claim 1 , wherein a heat pipe is disposed in a specific heat generation portion in the lower electrical casing and the upper electrical casing. The image forming apparatus according to claim 1 , further comprising a vent hole that takes in heat from a heating element adjacent to the lower electrical casing and the upper electrical casing.

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