Cooling device and image forming apparatus

Abstract

To effectively cool the object to be cooled. [Solution] A cooling device provided inside a higher-level device 10, comprising a cooling fan 31 that blows air onto a plurality of objects to be cooled 26 arranged on a predetermined arrangement surface M, wherein the airflow direction of the cooling fan 31 is inclined toward the arrangement surface M or a connecting plane J that connects the upper end of the nearest object to be cooled and the upper end of the furthest object to be cooled, toward the arrangement surface M or the connecting plane J, toward the direction toward the direction toward the arrangement surface M or the connecting plane J.

Description

Technical Field

[0001] The present invention relates to a cooling device and an image forming apparatus.

Background Art

[0002] In the case of a device that requires multifunctionality, a large number of subordinate devices for executing each function are intensively arranged inside the device housing. In this case, when the subordinate device has a heat source such as a substrate, a cooling device is provided together. For example, in the case of an image forming apparatus that requires multifunctionality, when a unit for executing each function has a heat source substrate, there is a cooling device that blows air to the substrate (see, for example, Patent Document 1). The cooling device of this image forming apparatus can switch the range of air blowing. When performing wide-range air blowing, both sides of the substrate can be cooled. When performing narrow-range air blowing, only the surface side of the substrate can be intensively cooled.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The conventional cooling device only changes the range of cooling, and there is room for improvement in effectively cooling a plurality of cooling objects.

[0005] An object of the present invention is to effectively cool a plurality of cooling objects.

Means for Solving the Problems

[0006] In order to solve the above problems, A cooling device installed inside a higher-level device, It is equipped with a cooling fan that blows air onto multiple objects to be cooled, which are placed on a predetermined surface. The cooling fan is configured to blow air in a direction that is inclined toward the placement surface or a connecting plane that connects the upper end of the object to be cooled closest to the upper end of the object to be cooled furthest away from the cooling fan, and toward the placement surface or the connecting plane.

[0007] Furthermore, the image forming apparatus was configured to incorporate the above-mentioned cooling device. [Effects of the Invention]

[0008] According to the present invention, it is possible to effectively cool multiple objects to be cooled. [Brief explanation of the drawing]

[0009] [Figure 1] This is a front view of the image forming apparatus according to this embodiment. [Figure 2] This is a front view of the transport section of an image forming apparatus. [Figure 3] This is an enlarged front view of the transport section. [Figure 4] This is a plan view of the area surrounded by guide plates for multiple paths in the transport section. [Figure 5] This is a right-side view of the cooling fan and all the control boards on the two base boards. [Figure 6] This is a side view diagram illustrating the relative positional relationship between the cooling fan and multiple control boards. [Figure 7] This chart shows an evaluation of the cooling effect for different inclination angles of the cooling fan. [Figure 8] This is a right side view of another embodiment (1) of the cooling device. [Figure 9] This is a right side view of another example of another embodiment (1) of the cooling device. [Figure 10] This is a right side view of another embodiment (2) of the cooling device. [Figure 11]It is a plan view of another aspect (3) of the cooling device. [Figure 12] It is a plan view of another aspect (4) of the cooling device. [Figure 13] It is a right side view of another aspect (5) of the cooling device. [Figure 14] It is a right side view of another aspect (6) of the cooling device.

Embodiments for Carrying Out the Invention

[0010] Hereinafter, a cooling device which is an embodiment of the present invention will be described in detail with reference to the drawings. This embodiment exemplifies a cooling device mounted on an image forming apparatus 10 as an upper device.

[0011] [Configuration of Image Forming Apparatus] FIG. 1 is a schematic diagram showing the schematic configuration and its arrangement of the image forming apparatus 10. In the following description, in the image forming apparatus 10, the upper side of the paper surface in FIG. 1 is referred to as "upper", the lower side of the paper surface is referred to as "lower", the left side of the paper surface is referred to as "left", and the right side of the paper surface is referred to as "right". Also, in the image forming apparatus 10, the back side of the paper surface in FIG. 1 is referred to as "rear", and the front side of the paper surface is referred to as "front". In a state where the image forming apparatus 10 is arranged on a horizontal plane, the front-rear and left-right directions of the apparatus are horizontal, and the up-down direction of the apparatus is vertical.

[0012] As shown in FIG. 1, the image forming apparatus 10 includes an image forming unit 13, an operation panel 15, a conveyance unit 20, and a supply unit 11.

[0013] The image forming unit 13 forms an image on a sheet as a recording medium based on image data acquired from an external device (not shown) via a communication unit (not shown), for example. Furthermore, an image reading unit may be added to the image forming apparatus 10 to read an image of a document placed on the document table or automatic document feeder (ADF) and obtain an image signal. In this case, the image reading unit scans and exposes the image of the document using the optical system of a scanning exposure apparatus, reads the reflected light with a line image sensor, and obtains an image signal. The image signal is subjected to processing such as A / D conversion, shading correction, and compression, and then input as image data to a control unit (not shown).

[0014] The image forming unit 13 forms an image on the paper consisting of four colors, C, M, Y, and K, according to the pixel values ​​of the four colors of each pixel in the processed original image. The image forming unit 13 includes four writing units 131, an intermediate transfer belt 132, a secondary transfer roller 133, a fixing unit 134, and the like.

[0015] The four writing units 131 are arranged in series (tandem) along the belt surface of the intermediate transfer belt 132, forming images of C, M, Y, and K colors. Each writing unit 131 has the same configuration except for the color of the image it forms. Each writing unit 131 comprises a light scanning unit 131a, a photoreceptor 131b, and a developing unit 131c. Furthermore, each writing unit 131 comprises a charging unit 131d, a cleaning unit 131e, and a primary transfer roller 131f.

[0016] During image formation, each writing unit 131 first charges the photoreceptor 131b with the charging unit 131d. Next, each writing unit 131 scans the photoreceptor 131b with a light beam emitted from the light scanning unit 131a based on the original image, forming an electrostatic latent image. Next, each writing unit 131 develops the image by supplying a colorant such as toner with the developing unit 131c. As a result, an image (toner image) is formed on the photoreceptor 131b.

[0017] The images formed on the photoreceptor 131b by each writing unit 131 are sequentially transferred onto the intermediate transfer belt 132 by the primary transfer roller 131f. As a result, an image consisting of each color is formed on the intermediate transfer belt 132. The intermediate transfer belt 132 is an image carrier that rotates by being wound around multiple rollers. After the primary transfer, each writing unit 131 has the colorant remaining on the photoreceptor 131b removed by the cleaning unit 131e.

[0018] During image formation, the transport unit 20 feeds paper in time with the timing when the image on the intermediate transfer belt 132 reaches the position of the secondary transfer roller 133. The image forming unit 13 receives paper from a manual feed tray (not shown) or a supply unit 11 via the transport unit 20. One of the rollers of the secondary transfer roller 133 presses against the intermediate transfer belt 132. The other roller of the pair constitutes one of several rollers that wind around the intermediate transfer belt 132. The paper fed to the image forming unit 13 has its image secondarily transferred from the intermediate transfer belt 132 by the pressure of the secondary transfer roller 133. The secondarily transferred paper is transported to the fixing unit 134 for fixing and discharged into a paper output tray (not shown). The fixing process involves heating and pressurizing the paper with the fixing roller 134a to fix the image onto the paper.

[0019] In Figure 1, the symbols R1 to R4 indicate the paper transport path. The transport path R1 is the path for transporting paper from the supply unit 11 to the downstream side. Transport path R2 is the path that transports paper from the manual feed tray to the downstream side. The transport path R3 is a path that passes the paper transported from the transport path R1 or R2 to the transfer position of the secondary transfer roller 133 and the fixing position of the fixing unit 134. Transport path R4 is the path through which the paper with the image formed on it, after passing through transport path R3, is ejected from the machine.

[0020] In Figure 1, the symbols R5 to R7 indicate the paper's reversal path. The reversal path R5 is a path that separates the paper to be reversed so that it is not transported to the transport path R4. Reversal path R6 is connected downstream of reversal path R4 and is a path used to move the paper out of the way in order to reverse it. The reversal path R7 is a path whose upstream end is connected to the boundary between reversal paths R5 and R6, and whose downstream end merges with the transport path R3.

[0021] When forming images on both sides of a sheet of paper, the paper with the image formed on the front is transported from transport path R3 to the inversion path R5, rather than to transport path R4. In this case, the entire sheet of paper is sent into the inversion path R6, then transported in the reverse direction and fed into the inversion path R7 from the rear end. As a result, the paper is inverted as it passes through the inversion path R7 and returned to transport path R3. In transport path R3, the paper passes through the transfer position of the secondary transfer roller 133 and the fixing position of the fixing unit 134, allowing an image to be formed on the back side as well.

[0022] The control panel 15 includes a display unit that displays various information to the operator and an operation unit that receives operation input from the operator.

[0023] The display unit consists of a color liquid crystal display or the like, and displays the operation screen and other information. The control unit can receive input from the operator and perform actions such as setting image formation parameters, issuing paper transport instructions, and stopping the device.

[0024] The supply unit 11 includes a paper tray for stacking and storing paper, and a pickup mechanism for picking up the top sheet of paper. The paper is then supplied to the image forming unit 13 via transport paths R1 and R3 according to commands from the operation panel 15.

[0025] The drum units, transfer units, fixing units, and toner bottle units for each color in the image forming unit 13 are detachable units from the housing 14. Similarly, the fixing unit 134, the supply unit 11, and the transport unit 20 (described later) are each unitized so that they can be detached from the housing 14.

[0026] [Conveying Section] Figure 2 is a front view of the transport unit 20, and Figure 3 is an enlarged front view of the transport unit 20. The transport unit 20 performs the transport of paper along the transport paths R1 to R4 and the reversal paths R5 to R7 described above. Figure 2 illustrates route 211, which constitutes part of transport route R1, and route 212, which constitutes part of transport route R3. It also illustrates routes 221 and 222, which constitute part of reversal route R7, and routes 231 and 232, which constitute part of reversal route R6. The transport paths R1 to R4 and the reversal paths R5 to R7 are provided with paper guide plates along each path and a plurality of transport rollers 24 arranged along the path.

[0027] Furthermore, each transport roller 24 can be of various types, including those that work in pairs to grip and feed the paper, and those that feed the paper individually in cooperation with a guide plate. Each conveyor roller 24 is individually driven by a motor, with a few exceptions. For example, in the case of a pair of conveyor rollers 24, only one of the rollers in the pair is driven by a motor. These motors require precise individual control over their operating amount, rotation direction, and operating timing. Therefore, each motor is equipped with its own control board 26, which includes a driver for controlling its operation. These control boards 26 are located in predetermined positions within the transport unit 20, as will be described later.

[0028] Specifically, the area S enclosed by the guide plates of the transport section 20's paths 212, 222, 231, and 232 serves as the installation area for each control board 26. This area S occupies a certain proportion of the overall volume of the transport section 20. Therefore, in order to effectively utilize the surplus space, the area S of the transport section 20 is used as the installation area for each control board 26.

[0029] Figure 4 is a plan view of the region S enclosed by the guide plates for each path 212, 222, 231, and 232. As shown in the figure, multiple base substrates 25 are arranged in the front-to-back direction within the region S. Although two base substrates 25 are shown as an example, one or three or more may also be used. Furthermore, even when the base substrate 25 is made longer and constructed as a single unit, it is still possible to enjoy the unique effects of the cooling device described later.

[0030] Each base board 25 is rectangular in shape, with its longitudinal direction oriented in the front-to-back direction, and is installed in area S with its surface horizontal. Multiple control boards 26 are arranged on the upper surface of each base board 25, with their surfaces parallel to each other and aligned in the front-to-back direction. Each control board 26 is erected vertically on the base board 25, with its surface perpendicular to the front-to-back direction. Region S is surrounded by guide plates for each path 212, 222, 231, and 232, and is a long space in the front-to-back direction. To efficiently arrange more control boards 26 in this region S, it is effective to orient each board surface perpendicular to the front-to-back direction and arrange them side by side in the front-to-back direction. Although six control boards 26 are shown as an example on a single base board 25, this number can be increased or decreased.

[0031] In this embodiment, the case where all control boards 26 have the same top, bottom, left, and right dimensions is illustrated. However, it is not essential that all control boards 26 have the same top, bottom, left, and right dimensions.

[0032] The upper surfaces of the two base boards 25 are located on the same horizontal plane. Each control board 26 is placed on this same horizontal plane, and this plane is defined as the "placement plane". Furthermore, on this arrangement plane, all control boards 26 are positioned such that their upper and lower edges and left and right edges coincide when viewed from the front and back directions. However, it is not essential that the upper and lower edges and left and right edges of all control boards 26 coincide.

[0033] Furthermore, on the two base boards 25, bundles of wires 27 are arranged along the front-to-back direction on both the left and right sides of the control boards 26 which are arranged front-to-back. These bundles of wires 27 are bundles containing various cables that supply power to each control board 26 and transmit and receive various signals. Furthermore, as shown in Figure 4, the cooling fan 31, which constitutes the cooling device, is positioned even further forward than the control board 26, which is located at the forefront in a plan view. The cooling fan 31 has an outlet 311 at its rear end that faces backward, and cools all of the control boards 26 by blowing air. In other words, each control board 26 corresponds to an "object to be cooled" by the cooling fan 31 that constitutes the cooling device.

[0034] [Cooling fan (cooling device)] Figure 5 is a right side view of the cooling fan 31 and all the control boards 26 on the two base boards 25. Here, the plane connecting the upper end of the control board 26 closest to the cooling fan 31 and the upper end of the control board 26 furthest from the cooling fan 31 is defined as the "connecting plane." The "connecting plane" is assumed to be a plane that is not tilted in the left-right direction perpendicular to the airflow direction of the cooling fan 31 in a plan view. In Figure 5, the dashed line labeled J indicates the connecting plane in a side view. Since each control board 26 is at the same height, the connecting plane J is horizontal in this embodiment. Furthermore, the symbol M in Figure 5 indicates the aforementioned arrangement surface. In this embodiment, the arrangement surface M is also horizontal.

[0035] The cooling fan 31 blows air towards the rear in a plan view and in a direction that slopes downward towards the rear in a side view. That is, the cooling fan 31 blows air in a direction that slopes closer to the placement surface M or connecting plane J as you move away from the cooling fan 31. In Figure 5, arrow C indicates the direction of airflow from the cooling fan 31. The downward inclination angle θ of the airflow direction C of the cooling fan 31 with respect to the placement surface M and the connecting plane J is preferably in the range of 3° to 10°. The cooling air blown out from the outlet 311 of the cooling fan 31 spreads slightly in all directions (up, down, left, and right). In this case, the direction in which the center of the cooling air travels is defined as the airflow direction C of the cooling fan 31.

[0036] The cooling fan 31 is supported by a support bracket 32 ​​to blow air in the above-described airflow direction C. However, the cooling fan 31 does not necessarily have to be supported so that the airflow direction C is fixed. For example, the cooling fan 31 may be supported so that its tilt angle can be adjusted via a manual tilt mechanism.

[0037] The outlet 311 of the cooling fan 31 should be positioned in front of the nearest forward control board 26 in the front-to-back direction. In this embodiment, an example is shown in which the rear end of the outlet 311 is positioned just in front of the front surface of the nearest forward control board 26. Furthermore, it is preferable that the upper end of the air outlet 311 is positioned above the upper end of the nearest and foremost control board 26 in the vertical direction. Moreover, it is preferable that the upper end of the air outlet 311 is positioned above the upper end of the furthest control board 26 in the vertical direction. The lower end of the air outlet 311 may be higher than the upper end of the foremost control board 26, but in this embodiment, they are at approximately the same height. Alternatively, the lower end of the air outlet 311 may be lower than the upper end of the foremost control board 26. Furthermore, "above the upper end of the control board 26" indicates that it is further away from the upper side in the direction normal to the placement surface M.

[0038] [Regarding the cooling effect of cooling devices] As a comparison with this embodiment, let us illustrate the case where the cooling fan 31 blows air parallel to the connecting plane J. When air is blown parallel to the connecting plane J, the cooling air passes parallel to the upper end of each control board 26. In this case, the cooling air does not enter the gaps between each control board 26, but exclusively cools the upper end of each control board 26, so efficient cooling is not possible. In contrast, the cooling fan 31 of the cooling device in this embodiment blows air towards the rear and far side, tilted downwards and closer to the connecting plane J. As a result, as shown in Figure 5, cooling air can easily enter the gap from the upper end of each control board 26, allowing the control boards 26, which are arranged front to back, to be cooled effectively.

[0039] In particular, each control board 26 is positioned in the region S surrounded by each guide plate of the transport unit 20. Each guide plate has a structure with few holes or gaps for the purpose of smoothly feeding paper, so region S tends to accumulate heat. However, the cooling fan 31 blows air in a direction that is roughly aligned with the front-to-back direction, which is the width direction of each guide plate of the transport unit 20. Therefore, the heat accumulated around each control board 26 can be effectively dissipated.

[0040] Generally, the cooling air blown out from the outlet 311 of the cooling fan 31 gradually diffuses as it travels further away. In Figure 3, the symbol R0 represents the diffusion range when air is blown parallel to the connecting plane J, and the symbol R1 represents the diffusion range when air is blown at a downward incline. When the airflow is directed downwards, the cooling air is directed towards the base substrate 25 and the control substrate 26, thus suppressing upward diffusion. As a result, more cooling air is blown onto each control substrate 26, making it possible to cool each control substrate 26 efficiently.

[0041] In particular, when the object to be cooled is a flat control board 26, the boards can be efficiently arranged in a dense area by bringing the board surfaces close together. Also, since the region S is a space along the front-to-back direction, each control board 26 is arranged in a line along the front-to-back direction. As shown in Figure 4, the cooling fan 31 blows air in the front-to-back direction in a plan view, and each control board 26 is oriented perpendicular to the airflow direction C (non-parallel) in a plan view. In contrast, the cooling fan 31 blows air from a position where the upper end of the outlet 311 is above the upper ends of all the control boards 26, with the aforementioned slope. As a result, cooling air can enter the gaps between the control boards 26, even those located far away, which are arranged in a front-to-back row. Therefore, the cooling fan 31 can effectively cool all of the control boards 26, even while arranging them densely according to the shape of the region S.

[0042] Furthermore, each control board 26 is positioned within a space enclosed on both sides in the left-right direction by bundles of wires 27, which are structural elements running in the front-to-back direction. Consequently, the diffusion of cooling air from the cooling fan 31 in the left-to-right direction is suppressed, allowing for sufficient airflow to cool even the control boards 26 located further away.

[0043] Furthermore, as shown in Figure 5, the outer wall of the housing 14 is close to the front of the cooling fan 31. In other words, the cooling fan 31 is positioned closer to the outer wall of the housing 14 of the image forming apparatus 10 than to each control board 26. The enclosure 14 has multiple door structures that can be opened outwards in various parts, and has many gaps and poor airtightness, so outside air can easily enter the inside of the enclosure 14. For this reason, the cooling fan 31, being located near the outer wall of the enclosure 14, can blow outside air or air cooled by outside air to each control board 26. The above describes an example in which the front of the cooling fan 31 is close to the outer wall of the enclosure 14 as an example of a structure in which outside air can easily enter. However, this is not limited to this example, even if the rear of the cooling fan 31 is not close to the outer wall of the enclosure 14, if the structure is such that outside air can easily enter. An example of a structure in which outside air can easily enter, other than proximity to the outer wall, is a structure in which there are no obstacles between the outer wall of the enclosure 14 and the cooling fan 31.

[0044] [Evaluation of the tilt angle of the cooling fan's airflow direction] The appropriate range of the inclination angle θ of the cooling fan 31 with respect to the connecting plane J in the airflow direction C was evaluated as follows. Figure 6 shows an example of the relative positional relationship between the cooling fan 31 and each control board 26 when performing evaluation. The front-to-back distance d1 from the outlet 311 of the cooling fan 31 to the front of the control board 26 closest to it is set to 1.3 [mm]. The front-to-back distance d2 from the cooling fan 31's outlet 311 to the front of the control board 26, which is furthest away, is set to 170.4 [mm]. The vertical distance h1 from the upper end of the air outlet 311 of the cooling fan 31 to the upper end of the control board 26 closest to it is set to 19.4 [mm]. The vertical width of the air outlet 311 of the cooling fan 31 is set to 11.7 mm.

[0045] As a temperature rise test, a paper feeding operation was performed for 90 minutes by the transport unit 20 until the temperature inside the machine stabilized, and airflow was blown by the cooling fan 31. When the blown air was not directed towards the substrate (tilt angle θ=0°), the control board 26 reached 58°C when the temperature inside the machine stabilized. However, by directing the blown air towards the substrate, the goal was to keep the control board below 48°C. In addition, the tilt angle θ of the airflow direction C of the cooling fan 31 was changed in 1° increments within the range of 1 to 12° to cool each control board 26. In this temperature rise test, cooling performance was evaluated based on the number of control boards 26 that met the target number of boards (12 in total). Figure 7 is a chart showing the evaluation of the cooling effect for each tilt angle. A rating of A indicates that all control boards 26 have been cooled to the target level. Evaluation B indicates that 6 to 11 control boards 26 were cooled to the target level. A rating of C indicates that fewer than six control boards 26 were cooled to the target temperature.

[0046] The evaluation revealed that when the airflow direction C of the cooling fan 31 had a continuous tilt angle θ of 1°, too few control boards 26 were cooled, and even at 2°, the number of cooled boards was insufficient. Furthermore, when the tilt angle θ was 11°, the number of control boards 26 being cooled became insufficient, and at 12°, the number of control boards 26 being cooled decreased significantly. Furthermore, it was possible to cool all control boards 26 within the range of tilt angle θ from 3° to 10°. This revealed that it is preferable for the inclination angle θ of the airflow direction C of the cooling fan 31 to be between 3° and 10°.

[0047] [Other forms of cooling devices (1)] In the example shown in Figure 5, the connecting plane J and the arrangement plane M are horizontal, and the airflow direction C of the cooling fan 31 is inclined with respect to them. However, the example is not limited to this configuration. The airflow direction C of the cooling fan 31 with respect to the connecting plane J or the placement plane M only needs to be inclined relative to it. For example, as shown in Figure 8, the airflow direction C of the cooling fan 31 is set to horizontally backward. On the other hand, the base board 25 and the control board 26 may be tilted so that the rear side of the connecting plane J and the arrangement plane M is on the side of the cooling fan 31 (upper side) in the vertical direction. In this configuration as well, the inclination angle θ is set to be between 3° and 10°. In this case as well, the airflow direction C of the cooling fan 31 with respect to the connecting plane J or the placement plane M is inclined in a relatively suitable direction, so the substrate 26 can be cooled in the same way as in the configuration of Figure 5.

[0048] Alternatively, as shown in Figure 9, the arrangement surface M and the airflow direction C of the cooling fan 31 may be kept horizontal, and only the connecting plane J may be relatively inclined. The connecting plane J is the plane connecting the upper end of the nearest control board 26 and the upper end of the furthest control board 26, and is adjusted by the height of these control boards 26. The control board 26 furthest from the nearest control board 26 is made higher, and the inclination angle θ is adjusted to be in the range of 3° to 10°. It is preferable that all other control boards 26 be at a height greater than or equal to all other control boards 26 that are closer to the cooling fan 31 than each of the control boards 26. In particular, it is more preferable that the upper end of each control board 26 is at the height of the connecting plane J. Alternatively, the height of each control board 26 may be adjusted by inserting spacers or the like between the base board 25 and each control board 26, without changing the height of each control board 26. In these cases as well, the airflow direction C of the cooling fan 31 with respect to the connecting plane J is tilted in a relatively favorable direction, so the control board 26 can be cooled in the same way as in the configuration of Figure 5.

[0049] [Other forms of cooling devices (2)] In the example shown in Figure 5, the tilt angle θ of the airflow direction C of the cooling fan 31 was fixed, but it is not limited to this. For example, as shown in Figure 10, a variable mechanism 33 consisting of a motor-driven tilt mechanism or the like may be added to the cooling system configuration. The variable mechanism 33 supports the cooling fan 31 and allows it to be tilted around an axis along the left-right direction to change the airflow direction C. This variable mechanism 33 allows the tilt angle θ of the airflow direction C of the cooling fan 31 to be adjusted arbitrarily.

[0050] The motor of the variable mechanism 33 may be connected to the control device 34, and the amount of operation may be arbitrarily controlled to adjust the tilt angle θ of the airflow direction C of the cooling fan 31. For example, the control device 34 may be equipped with an input means for a person to input a value for the tilt angle θ, and the airflow direction C of the cooling fan 31 may be adjusted accordingly.

[0051] Furthermore, the control device 34 may be connected in a communication manner to another control device that comprehensively controls the transport of paper by the transport unit 20. In this case, the control device 34 can obtain paper transport control information from other control devices and recognize which control board 26 will drive the motor. Furthermore, the control device 34 may control the motor of the variable mechanism 33 so that air is blown toward the control board 26, which is in use and drives the motor. For example, in Figure 10, the control board 26 in use is indicated by reference numeral 26a. The control device 34 controls the motor of the variable mechanism 33 so that the airflow direction C of the cooling fan 31 is directed toward the control board 26a. In this case, the control device 34 may individually store the tilt angle θ to which the airflow direction C is directed for each control board 26. Then, when the control device 34 identifies the control board 26a in use, it controls the motor of the variable mechanism 33 to achieve the corresponding tilt angle θ. Each control board 26 tends to heat up when the connected motor is driven. In this case, the control device 34 performs the above-mentioned control to focus on cooling the control board 26 that is likely to heat up, thereby enabling efficient cooling.

[0052] Furthermore, regarding the control of the control device 34, if multiple control boards 26 are in use, the tilt angle θ may be averaged and air may be blown to the multiple control boards 26. Alternatively, the control device 34 may control the variable mechanism 33 so that it sequentially switches to individual tilt angles θ relative to the multiple control boards 26 and blows air. In this case, the control device 34 may shorten the period for switching to individual tilt angles θ and control the variable mechanism 33 so that it repeats many times and blows air in each direction.

[0053] Furthermore, the control device 34 may be connected to each control board 26 in a communicative manner, rather than being another control device that comprehensively controls the transport unit 20. In that case, the control device 34 can recognize which control board 26 is in use by observing when each control board 26 starts controlling the motor drive.

[0054] [Other forms of cooling devices (3)] The cooling device may be configured to blow air while rotating the airflow direction C of the cooling fan 31 along the placement surface M or connecting plane J within a certain angular range. For example, as shown in Figure 11, a rocking mechanism 35 that causes the cooling fan 31 to oscillate around an axis along the vertical direction may be added to the configuration of the cooling device. The oscillating mechanism 35 supports the cooling fan 31 and causes it to oscillate back and forth around an axis along the vertical direction. This allows the cooling fan 31 to oscillate back and forth from side to side along the placement surface M or connecting plane J in the airflow direction C.

[0055] This oscillating mechanism 35 expands the airflow range of the cooling fan 31 in the left-right direction, enabling wider cooling of each control board 26 in the left-right direction. For example, even if the control board 26 is wide in the left-right direction, the entire board can be effectively cooled. Furthermore, the oscillating mechanism 35 can be applied to the various forms of cooling devices described above.

[0056] [Other forms of cooling devices (4)] In the example shown in Figure 5, the left and right ends of each control board 26 coincide when viewed from the front-to-back direction, but the arrangement is not limited to this. For example, as shown in Figure 12, the position of the rightmost end of each control board 26 may be shifted to the right, which is further outward, as it moves away from the cooling fan 31.

[0057] Note that the straight line L in Figure 12 is a straight line connecting the right ends of each control board 26. It is preferable that the right ends of each control board 26 be aligned along this straight line L, but they do not have to be aligned. However, it is preferable that the right end of each control board 26 be to the right of the other control board 26 that is closer to the cooling fan 31 (front side) than that control board 26.

[0058] With the above arrangement, cooling air blown from the cooling fan 31 enters the gaps between the control boards 26 from the right edge of each control board 26. Therefore, the cooling device can more effectively cool the control boards 26 that are further away.

[0059] Furthermore, the rightmost end of each control board 26 should be at the aforementioned positions, and the width of each control board 26 in the left-right direction does not need to be uniform. Alternatively, the left end of each control board 26 may be positioned so that it is moved to the left, which is further outward, as it moves away from the cooling fan 31.

[0060] Furthermore, the arrangement of each control board 26 described above can be applied to the various forms of cooling devices already described.

[0061] [Other forms of cooling devices (5)] In the example shown in Figure 5, the entire cooling fan 31 was tilted to achieve airflow with a downward slope angle θ, but the method is not limited to this. For example, as shown in Figure 13, the cooling fan 31 is positioned horizontally, and the inner lower end of the outlet 311 is widened so that it faces downwards. This makes it possible to direct the airflow direction C of the cooling fan 31 downwards at an inclination angle θ.

[0062] [Other forms of cooling devices (6)] In the example shown in Figure 5, the entire cooling fan 31 was tilted to achieve airflow with a downward slope angle θ, but the method is not limited to this. For example, as shown in Figure 14, the cooling fan 31 may be positioned horizontally, and a deflection plate 36 may be provided at the upper end of the air outlet 311 at the same height to change the direction of airflow. The deflection plate 36 is provided with its lower surface 361 aligned with the lower surface of the inner upper end of the air outlet 311. The lower surface 361 of the deflection plate 36 has inclined sections 362 and 363 at the front and rear, which are inclined diagonally downward and rearward. The inclined portion 362 has its lower surface inclined diagonally downward and rearward at an angle θ1, and the inclined portion 363 has its lower surface inclined diagonally downward and rearward at an angle θ2. The inclination angle θ1 of the inclined portion 362 closer to the cooling fan 31 has a greater downward slope than the inclination angle θ2 of the inclined portion 363 further away.

[0063] A bottom view of the deflection plate 36 is added to the lower part of Figure 14. As shown in the figure, the inclined section 362 near the cooling fan 31 has a structure in which it is divided in multiple places in the left-right direction. This allows a portion of the cooling air to travel at an inclination angle θ1, and the remaining portion to travel at an inclination angle θ2.

[0064] As described above, by setting the airflow direction to two different directions along different inclination angles θ1 and θ2, it becomes possible to apply cooling air over a wide area in the front-to-back direction.

[0065] Furthermore, the airflow at near and far can be adjusted by changing the ratio to which the inclined section 362 near the cooling fan 31 is divided. Furthermore, inclined sections may be provided in three or more locations in the front-to-back direction. While the example given illustrates a case where the inclination angle θ2 of the inclined section 363 furthest from the cooling fan 31 is smaller than θ1, the relationship between magnitude may be reversed. Also, the inclination angles θ1 and θ2 may be equal.

[0066] [others] The embodiments of the present invention have been described above. However, the present invention is not limited to the embodiments described above. For example, in the embodiments, a component integrally formed from a single member may be replaced with a component divided into multiple members that are connected or fixed to each other. Also, a component formed by connecting multiple members may be replaced with a component integrally formed from a single member. Furthermore, details shown in the embodiments can be modified as appropriate without departing from the spirit of the invention.

[0067] For example, the cooling device described above is illustrated as being mounted on the transport section 20 of the image forming apparatus 10, but it is not limited to this configuration. Cooling devices of the various types described above may be mounted on other components or units of the image forming apparatus 10. Furthermore, the above-mentioned cooling device can also be applied to devices other than the image forming apparatus 10 that have a heat-generating chamber inside the housing. Furthermore, the cooling device may also use other heat-generating elements, components, mechanisms, or devices other than the control board 26 as objects to be cooled. [Explanation of Symbols]

[0068] 10. Image forming apparatus (higher-level equipment) 11 Supply section 12 Image reading unit 13 Image forming unit 14 cabinets 15. Control Panel 20 Conveying section Routes 211, 212, 221, 222, 231, 232 24 Conveyor rollers 25 Base board 26,26a Control board (object to be cooled) 27 Bundled wire (structure) 31 Cooling fan 311 Air outlet 32 Support brackets 33 Variable Mechanism 34 Control device 35. Oscillating mechanism 36 Deflection plate 362,363 Slope 131 Writing section C Air blow direction J connection plane L straight line M placement surface S area R1~R4 Transport Route R5~R7 Reversal Path θ,θ1,θ2 Inclination angle

Claims

1. A cooling device installed inside a higher-level device, It is equipped with a cooling fan that blows air onto multiple objects to be cooled, which are placed on a predetermined surface. A cooling device that inclins the airflow direction of the cooling fan toward the placement surface or a connecting plane that connects the upper end of the object to be cooled closest to the upper end of the object to be cooled furthest away from the cooling fan, and toward the placement surface or the connecting plane, so as to move toward the placement surface or the connecting plane.

2. The cooling device according to claim 1, wherein the plurality of objects to be cooled are substrates.

3. The cooling device according to claim 1, wherein the above-level device is an image forming apparatus.

4. The cooling device according to claim 3, wherein a plurality of objects to be cooled are arranged in an area surrounded by guide plates that constitute a transport path for a recording medium on which an image is formed.

5. The cooling device according to claim 1, wherein multiple objects to be cooled are cooled in a space between structures aligned with the airflow direction of the cooling fan in a plan view, and air is blown by the cooling fan within this space.

6. The cooling device according to claim 1, wherein the direction of airflow from the cooling fan is inclined by 3 to 10° from a state parallel to the arrangement surface or the connecting plane.

7. The cooling device according to claim 1, wherein the cooling fan is positioned closer to the outer wall of the housing of the upper device than to the object to be cooled.

8. A variable mechanism for changing the tilt angle of the airflow direction of the cooling fan, The variable mechanism is equipped with a control device, The cooling device according to claim 2, wherein the control device controls the variable mechanism so that the airflow direction of the cooling fan is directed towards the board that is in use among the plurality of boards.

9. The cooling device according to claim 1, wherein the airflow direction of the cooling fan is rotated within a certain angular range along the arrangement surface or the connecting plane while air is being blown.

10. With respect to the direction of airflow from the cooling fan when viewed normal to the aforementioned arrangement surface, the multiple substrates are arranged so as to be non-parallel to the direction of airflow from the cooling fan. The cooling device according to claim 2, wherein the cooling fan blows air from a position that is further away from the substrate than the upper end of the cooling fan is furthest away from the mounting surface.

11. The cooling device according to claim 2, wherein each of the plurality of substrates has a height from the placement surface that is greater than or equal to that of all other substrates that are closer to the cooling fan than the substrate in question.

12. The cooling device according to claim 1, wherein the cooling fan blows air with a wide range over the angle range of the inclination.

13. The cooling device according to claim 10, wherein each of the plurality of substrates has a substrate-side edge in a direction perpendicular to the airflow direction of the cooling fan when viewed normal to the arrangement surface, and that edge is located further out than all other substrates that are closer to the cooling fan than that substrate.

14. An image forming apparatus equipped with a cooling device according to any one of claims 1 to 13.

Images