Display unit

Abstract

To achieve a heat dissipation configuration corresponding to vertical installation and horizontal installation.SOLUTION: A display unit has: a display module; a plurality of fans for heat dissipation; detection means that detects whether the installation state of the display unit is vertical installation or horizontal installation; and control means that controls the rotation of the plurality of fans on the basis of the installation state.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a display device. [Background technology]

[0002] In recent years, display devices have come to use high-definition display panels and LEDs (Light Emitting Diodes) as backlight sources. As a result, the display performance and system control performance of display devices have improved, but power consumption has also increased, leading to increased heat generation from various electrical components such as system circuits and power supply circuits, as well as from circuit boards.

[0003] Furthermore, as vertically shot videos become more common, improvements in the display performance and system control performance of display devices are required to enable viewing of vertically shot videos more clearly. For example, in live broadcasts and e-commerce, display devices are required to support a wide color gamut and to display high dynamic range (HDR).

[0004] Under these circumstances, there is a need for a single display device that can be used in both landscape and portrait orientations. To address this need, methods for cooling the main heat-generating components of a display device have been devised, assuming that a single display device can be used in both landscape and portrait orientations.

[0005] Patent Document 1 discloses a display device that has a heat dissipation structure that is compatible with both horizontal and vertical installation by providing an intake fan and an exhaust fan.

[0006] Patent Document 2 discloses a display device that can be cooled by detecting the length and width with a temperature sensor and changing the rotation speed of a fan. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Patent Publication No. 2021-124593 [Patent Document 2] Patent No. 3625811 Summary of the Invention [Problem to be solved by the invention]

[0008] However, Patent Document 1 had the problem of requiring a large and long duct from intake to exhaust. Furthermore, even if the fan rotation speed is calculated and adjusted using a temperature sensor as in Patent Document 2, it is difficult to reduce temperature unevenness on the surface if the overall heat generation amount increases. In situations where temperature unevenness on the surface is large, it can change due to temperature unevenness in the display panel and backlight, which can adversely affect image quality, such as uneven brightness and chromaticity.

[0009] In view of the above, an object of the present invention is to realize a heat dissipation configuration that is compatible with both vertical and horizontal installation. [Means for solving the problem]

[0010] The display device has a display module, a plurality of fans for heat dissipation, a detection means for detecting whether the display device is installed vertically or horizontally, and a control means for controlling the rotation of the plurality of fans based on the installation state. [Effects of the Invention]

[0011] According to the present invention, a heat dissipation configuration that is compatible with both vertical and horizontal installations can be realized. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is an exploded perspective view of a display device according to a first embodiment when installed horizontally. [Figure 2] 1 is an exploded perspective view of a display device according to a first embodiment when installed horizontally. [Figure 3] FIG. 2 is a front view illustrating the temperature unevenness distribution of the display device according to the first embodiment. [Figure 4] FIG. 2 is a rear view of the display device according to the first embodiment. [Figure 5] FIG. 2 is a block diagram illustrating fan control of the display device according to the first embodiment. [Figure 6] FIG. 10 is a rear view of the display device according to the second embodiment. [Figure 7] FIG. 10 is a rear view of a display device according to a third embodiment. [Figure 8] FIG. 10 is a rear view of the display device according to the fourth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0013] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0014] [First embodiment] A first embodiment of the present invention will be described below with reference to FIGS.

[0015] Fig. 1 is an exploded perspective view of the display device according to the first embodiment when it is installed horizontally, and Fig. 2 is an exploded perspective view of the display device according to the first embodiment when it is installed horizontally.

[0016] As shown in FIGS. 1 and 2, the display device 1 includes a display panel 2 for displaying images, and the surrounding exterior includes a bezel 7 on the front side and a rear cover 11 on the rear side. The bezel 7 and rear cover 11 are often made of metal such as aluminum or iron and are formed by pressing or machining, but they may also be molded from a resin material. The display panel 2 is a display module such as a liquid crystal display panel or an OLED panel (Organic Light Emitting Diode). Other panels than those illustrated may also be used. In this embodiment, a case where the display panel 2 is a liquid crystal display panel will be described.

[0017] A backlight unit 3 is disposed behind the display panel 2. The backlight unit 3 mainly includes an optical sheet 9 disposed behind the display panel 2, and a light source substrate 8 mounted with multiple light sources (not shown) disposed behind the optical sheet 9. The backlight unit 3 is covered by a case component such as a chassis 10. In this embodiment, a backlight using light-emitting diodes (LEDs) is used as the light source, but this is not limiting. The optical sheet 9 is a sheet- or plate-shaped member that optically adjusts the light from the light source substrate 8 and irradiates it onto the display panel 2. It is composed of a diffuser plate for uniforming the amount of light in the surface direction and a prism sheet for controlling the direction of light emission. In this embodiment, multiple optical sheets 9 are provided. Materials used for the optical sheet 9 include polycarbonate and polyethylene terephthalate. Considering strength and heat dissipation and uniformity of the heat from the light source substrate 8, the chassis 10 is preferably made of a metal material such as iron, aluminum, or an alloy thereof, formed by pressing or machining.

[0018] Various circuit boards are arranged between the chassis 10 and the rear cover 11. That is, the circuit boards are arranged inside the exterior of the display device 1. These include a system circuit board 6 that performs system control of the display device 1 and a power circuit board 4 that supplies power. In this embodiment, a fan 5 is provided in the display device 1 to cool the above-mentioned boards and the backlight unit 3. Furthermore, air intake holes 12 and 13 and an exhaust hole 14 are provided in the rear cover 11 to form heat dissipation paths for the various boards. For efficient cooling in a horizontal installation as shown in FIG. 1, the air intake hole 12 is provided below the rear cover 11, and the exhaust hole 14 and fan 5 are provided above. On the other hand, in a vertical installation as shown in FIG. 2, the air intake hole 13 is provided near the power circuit board 4, which generates a large amount of heat, in this case, on the side of the rear of the rear cover, to form a heat dissipation path for exhausting heat via the exhaust hole 14 and fan 5. The air intake holes and exhaust holes are typically shaped as multiple round holes with a diameter of approximately 1 to 5 mm, but polygonal or irregular shapes are also acceptable. 1 and 2, air intake holes 12 and 13 are provided on the rear side of rear cover 11, but air intake holes may also be provided on the bottom or side of the rear cover. Furthermore, if bezel 7 is extended, air intake holes may also be provided on the bottom or side of bezel 7. In the case of horizontal installation, an air flow path is formed from air intake hole 12 to exhaust hole 14. This cools system circuit board 6, power supply circuit board 4, backlight unit 3, etc. Furthermore, in the case of vertical installation as shown in FIG. 2, an air flow path is formed from air intake hole 13 to exhaust hole 14. This cools system circuit board 6, power supply circuit board 4, backlight unit 3, etc., as in FIG. 1.

[0019] However, simply changing the flow path to accommodate horizontal or vertical installation may result in temperature unevenness in the display panel 2 or the backlight unit 3. Fig. 3(a) is a front view simulating the temperature unevenness distribution when the display device according to the first embodiment is installed horizontally. Fig. 3(b) is a front view simulating the temperature unevenness distribution when the display device according to the first embodiment is installed vertically.

[0020] As shown in Figure 3(a), in the case of horizontal installation, temperature unevenness (horizontal) 15 occurs in the center and upper part. On the other hand, as shown in Figure 3(b), in the case of vertical installation, temperature unevenness (vertical) 16 occurs in the center and left part. This is because the temperature unevenness shifts to the left side where the fan is located and the exhaust temperature is high. The area shown in Figures 3(a) and 3(b) is an area with a higher temperature than the surrounding area, and the characteristics of the LCD and LED change, resulting in a change in display image quality. This also shortens the lifespan of the display panel and the LED, causing image quality degradation such as brightness degradation and chromaticity degradation. Furthermore, temperature unevenness (vertical) 16 tends to be wider and higher in temperature than temperature unevenness (horizontal) 15. This is because the heat dissipation flow path of the display device 1 is longer in the vertical installation than in the horizontal installation.

[0021] Therefore, a method for changing the fan control method in the vertical installation from that in the horizontal installation to realize an efficient heat dissipation flow path will be described with reference to FIGS.

[0022] Fig. 4(a) is a rear view of the display device according to the first embodiment when it is installed horizontally, and Fig. 4(b) is a rear view of the display device according to the first embodiment when it is installed vertically.

[0023] First, as shown in Fig. 4(a), a flow path (horizontal) 17 is formed from the lower intake holes to the upper fans 5a to 5d so as to cool the power supply circuit board 4, the system circuit board 6, the light source board, and the chassis 10 to which the light source board is in contact. There is no limitation on the number of fans, but it is desirable to provide two or more in order to dissipate and uniformly distribute heat from the backlight unit and the light source board. On the other hand, as shown in Fig. 4(b), a case will be described in which the power supply circuit board 4 is installed vertically so as to be located on the lower side.

[0024] A vertical air flow path 18 is formed from the lower intake port to the fans 5a to 5d located on the upper right side to cool the chassis 10 to which the power supply circuit board 4, system circuit board 6, and light source board are connected. Here, the rotation speed or exhaust flow rate of each fan is changed. In FIG. 4(a), a flow path from the bottom to the top can be formed by driving each fan at a constant rotation speed. In the case of a vertical installation, the fans are unevenly positioned, so by changing the rotation speed, or exhaust flow rate, of each fan, it is possible to further reduce the temperature unevenness (vertical) 16. This reduces temperature unevenness in the backlight unit and display panel.

[0025] Here, the rotation speed of each fan is set to gradually increase from the fan located at the bottom to the fan located at the top. That is, the rotation speed of fan 5a is the slowest, followed by fan 5b, fan 5c, and fan 5d. The heat dissipation flow path is gradually larger from the bottom, with flow paths 19, 20, 21, and 22 leading to each fan, from the main flow path (vertical) 18 to each fan, and the exhaust volume increases toward the top. This makes it possible to reduce the range of temperature unevenness (vertical) 16 that occurs on the upper side of the display device, or on the side where the fans are located.

[0026] Next, how to control the fans will be described. Fig. 5 is a block diagram showing fan control in the display device according to the first embodiment.

[0027] As shown in FIG. 5, the display device 1 includes a video signal input unit 29, operation switches 28, a control unit 23, an image quality correction unit 24, a fan control unit 25, and a display panel control unit 26. These components are housed in an exterior. The display device 1 also includes a backlight drive unit 27, fan drive units 30a-30d, a power supply unit 31, a display panel 2, a backlight unit 3 (light source board 8), fans 5a-5d, and an acceleration sensor 32. The video signal input unit 29 is connected to an external device such as a video signal output device or a PC, and a video signal 40 is input from the connected device to the display device 1. The video signal input unit 29 outputs the video signal 40 input from the external device such as a PC to the image quality correction unit 24 in the control unit 23. The input from the external device may be via a wired connection via a cable or a wireless connection using a predetermined wireless communication standard. The video signal may be either an analog signal or a digital signal.

[0028] Image quality correction unit 24 corrects the video signal based on the installation environment of display device 1 and signals input from operation switch 28. Control unit 23 outputs drive conditions based on this image quality correction to display panel control unit 26 and backlight drive unit 27. Note that control unit 23 may reflect the contents of a user's operation input to display device 1 via operation switch 28 (for example, a change in display brightness) in the output signal.

[0029] The display panel control unit 26 drives the display panel 2 based on the drive conditions input from the control unit 23. The backlight drive unit 27 drives the backlight unit 3 based on the drive conditions input from the control unit 23.

[0030] The fan control unit 25 determines the fan drive conditions and outputs a signal to the fan drive unit. The fan drive units 30a to 30d drive the fans 5a to 5d based on the drive conditions input from the fan control unit 25. The fan drive conditions use the fan drive voltage value. Note that the fan rotation speed may also be used as the fan drive conditions. The fan drive conditions can also use the output value of the control unit that controls the drive of the fan, or an actually measured value such as the fan drive voltage. For example, the fan rotation speed information output from a fan with a rotation speed detection function, the DC voltage value input to the fan to drive the fan, or the duty ratio of the pulse voltage in the case of PWM (Pulse Width Modulation) drive, can be used.

[0031] When determining the fan drive conditions, the temperatures detected by the temperature sensors (not shown) provided in the display device 1, the drive conditions of the backlight unit 3, etc. may be reflected.

[0032] In this embodiment, the acceleration sensor 32 detects the direction of gravity and determines whether the display device 1 is installed horizontally or vertically. Based on the determined information, the fan control unit 25 controls the fan drive units 30a to 30d to change the rotation speed of the fans 5a to 5d. For example, in horizontal installation, the rotation speeds of the fans 5a to 5d are the same, whereas in vertical installation, the rotation speeds of the fans 5a, 5b, 5c, and 5d are gradually increased. As described above, this configuration allows the exhaust volume of each fan to gradually increase from the bottom, thereby reducing the range of temperature unevenness (vertical) 16 that occurs on the upper side of the display device or on the side where the fans are located. By varying the rotation speed of the fans depending on the installation state in this way, temperature unevenness in the display device can be reduced.

[0033] Although it has been explained that the fan rotation speed gradually increases from bottom to top when installed vertically, for example, only the lower fan 5a may have a low rotation speed, or only fan 5d may have a high rotation speed. It is sufficient if there is a distinction between the rotation speed of the lower fan and that of the upper fan.

[0034] The acceleration sensor used to determine whether the display is installed horizontally or vertically may be located within the display device, and may be mounted on one of the circuit boards. Other sensors or methods may also be used to determine the installation status. For example, the backlight unit 3 may be equipped with multiple temperature sensors, and the temperature distribution may be identified from the temperature sensors, the installation status may be read, and the fan rotation speed may be controlled to reduce temperature unevenness. Furthermore, when the installation orientation is determined using a stand or wall-mounting member, a sensor capable of determining the installation status, such as a pressure sensor, may be provided on the installation section of the display device to perform the determination.

[0035] As described above, the configuration of this embodiment makes it possible to implement a heat dissipation configuration that is compatible with both vertical and horizontal installation of the display device, and in either installation mode, it is possible to improve temperature unevenness in the backlight and display panel, thereby reducing the impact on image quality.

[0036] [Second embodiment] Next, a second embodiment of the present invention will be described with reference to the drawings, with the configuration of the second embodiment being described in detail with respect to the parts that are different from the first embodiment.

[0037] FIG. 6 is a rear view of the display device according to the second embodiment.

[0038] Figure 6 shows the case of a vertical installation. As in the first embodiment, a heat dissipation flow path is formed by the fan and the intake holes, but fan 205a is stopped. This allows air to be drawn in through the opening of fan 205a, further increasing the flow rate for cooling the upper part. Flow path a 219 serves as an intake flow path, and flow paths b 220, c 221, and d 222 are formed as exhaust flow paths for fans 205b, 205c, and 205d. In other words, by stopping some of the fans, in this case the lower fan, the intake flow rate can be increased, thereby improving the cooling effect.

[0039] [Third embodiment] Next, a third embodiment of the present invention will be described with reference to the drawings. In this embodiment, the configuration of the parts that are different from the first to second embodiments will be described in detail.

[0040] Fig. 7(a) is a rear view of the display device according to the third embodiment when it is installed horizontally, and Fig. 7(b) is a rear view of the display device according to the third embodiment when it is installed vertically.

[0041] In Figures 7(a) and (b), fans 305a, 305b, 305c, and 305d are shown, but fans 305a and 305d are installed as fans capable of both intake and exhaust. In a horizontal installation such as that shown in Figure 7(a), a flow path (horizontal) 17 is formed as in the first embodiment, and both fans are used as exhaust fans. On the other hand, in a vertical installation as shown in Figure 7(b), a flow path 318 is formed, and fan 305a, located at the bottom, is driven as an intake fan. As a result, flow path a 319 becomes an intake flow path, and flow paths b 320, c 321, and d 322 are formed as exhaust flow paths for fans 305b, 305c, and 305d. Note that if the vertical installation is reversed, fan 305d may be driven as an intake fan. The fan control is the same as in Figure 5, with the fan control unit and fan drive unit controlling the fan to rotate in the intake direction.

[0042] As described above, with the configuration of this embodiment, by making some of the fans, in this case the lower fans, fans that can be used for both intake and exhaust, the intake flow rate can be increased, thereby improving the cooling effect.

[0043] [Fourth embodiment] Next, a fourth embodiment of the present invention will be described with reference to the drawings. In this embodiment, the configuration of parts that are different from the first to third embodiments will be described in detail.

[0044] Fig. 8(a) is a rear view of the display device according to the fourth embodiment when it is installed horizontally, and Fig. 8(b) is a rear view of the display device according to the fourth embodiment when it is installed vertically.

[0045] As shown in Figure 8(a), the horizontal installation is described below. Fans 405a and 405b are placed on the bottom, and fans 405c and 405d are placed on the top. All of these fans are capable of both intake and exhaust. Furthermore, the power supply circuit board 4 and the system circuit board 6, which are representative internal circuit boards, are placed between them. Furthermore, airflow direction plates 411 are provided between the horizontally arranged fans. These prevent interference between the horizontal fan airflows and function in the vertical installation described below. Airflow direction plates 411 are preferably made of a plate material such as resin or metal. Airflow direction plates 411 are fixed to the chassis 10. Any fixing method, such as rivets, screws, or double-sided tape, can be used. With this configuration, in the horizontal installation, fans 405a and 405b are used as intake fans and fans 405c and 405d are used as exhaust fans, forming a horizontal flow path 417.

[0046] Next, we will explain the case of vertical installation, as shown in Figure 8(b). Fans 405a and 405c operate as intake fans, and fans 405b and 405d operate as exhaust fans, thereby forming a flow path (vertical) 418 for the entire unit. Air is drawn in from each fan, flow paths a419 and c421 serve as intakes, and flow paths b420 and d422 serve as exhausts. By installing air direction plate 411 along the circuit board and fan, it promotes cooling of the circuit board and also has the effect of cooling the center in a concentrated manner to address temperature unevenness in the backlight unit.

[0047] As described above, the configuration of this embodiment makes it possible to implement a heat dissipation configuration that is compatible with both vertical and horizontal installation of the display device, and in either installation mode, it is possible to improve temperature unevenness in the backlight and display panel, thereby reducing the impact on image quality.

[0048] [Other embodiments] Although the preferred embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and various modifications and changes are possible within the scope of the gist of the present invention.

[0049] The disclosure of this embodiment includes the following configuration.

[0050] (Configuration 1) A display device, A display module; Multiple fans for heat dissipation, a detection means for detecting whether the display device is installed vertically or horizontally; a control means for controlling the rotation of the plurality of fans based on the installation state; A display device comprising:

[0051] (Configuration 2) 2. The display device according to configuration 1, wherein the display module includes a liquid crystal panel and a backlight unit that illuminates the liquid crystal panel.

[0052] (Configuration 3) 2. The display device according to claim 1, wherein the display module comprises an OLED panel.

[0053] (Configuration 4) 4. The display device according to any one of configurations 1 to 3, wherein the detection means detects whether the display device is installed vertically or horizontally based on the direction of gravity.

[0054] (Configuration 5) 4. The display device according to any one of configurations 1 to 3, wherein the detection means detects an internal temperature distribution.

[0055] (Configuration 6) The display device according to any one of configurations 1 to 5, characterized in that when the display device is installed vertically, the rotation speed of the fan located on the upper side of the display device is higher than that of the fan located on the lower side.

[0056] (Configuration 7) 7. The display device according to any one of configurations 1 to 6, wherein the fan located below the display device is stopped when the display device is installed vertically.

[0057] (Configuration 8) The fan is a fan capable of both intake and exhaust, The display device according to any one of configurations 1 to 7, wherein the change means controls the fan located below the display device to intake air and the fan located above the display device to exhaust air when the display device is installed vertically.

Claims

1. A display device, A display module; Multiple fans for heat dissipation, a detection means for detecting whether the display device is installed vertically or horizontally; a control means for controlling the rotation of the plurality of fans based on the installation state; A display device comprising:

2. Further, the device has a means for detecting an internal temperature distribution, The control means controls the rotation of the plurality of fans based on the temperature distribution.

2. The display device according to claim 1.

3. 2. The display device according to claim 1, wherein, when the display device is installed vertically, the rotation speed of the fan located on the upper side of the display device is higher than that of the fan located on the lower side.

4. 2. The display device according to claim 1, wherein the control means stops the fan located below the display device when the display device is installed vertically.

5. The fan is a fan capable of both intake and exhaust, 2. The display device according to claim 1, wherein the control means controls the fan located below the display device to intake air and the fan located above the display device to exhaust air when the display device is installed vertically.

6. 2. The display device according to claim 1, wherein the detection means detects whether the display device is installed vertically or horizontally based on the direction of gravity.

7. 2. The display device according to claim 1, wherein the display module comprises a liquid crystal panel and a backlight unit for illuminating the liquid crystal panel.

8. The display device according to claim 1 , wherein the display module comprises an OLED panel.

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