Air-cooling mechanism, and projector

Abstract

To provide an air-cooling mechanism that can take in gas even when abnormality occurs in supply of the gas, and a projector.SOLUTION: An air-cooling mechanism has an intake port and a fan, and is attached to a first housing that uses the fan to take in gas to the inside from the intake port. The air-cooling mechanism comprises: a second housing that has a first opening, a second opening, and a third opening; and an air blowing unit that causes gas to flow into the second housing through the first opening. The second opening in the second housing communicates with the intake port in the first housing. The third opening communicates with the outside of the second housing.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to an air-cooling mechanism and a projector equipped with the same. [Background technology]

[0002] Conventionally, there are projectors that modulate illumination light from a light source into image light using a light modulation element and project the modulated image light. Such projectors include a board for generating image light and a fan for cooling the light source and the light modulation element.

[0003] For example, Patent Document 1 describes a projector in which gas cooled by a cooling device is circulated and supplied within a duct. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2009-222998 A Summary of the Invention [Problem to be solved by the invention]

[0005] Recently, projectors have begun to be used in various outdoor locations. When using a projector outdoors, dust and other particles contained in the inhaled gas may adhere to the projector, which corrodes the substrate. Corrosive particles that corrode substrates include, for example, salt or sulfur. These corrosive particles are found floating in the air at the sea, in hot springs, and during fireworks. Using a projector in such conditions will accelerate the deterioration of the substrate inside the projector.

[0006] In view of this, it is conceivable to use an air-cooling mechanism to supply clean gas to the projector, which would prevent deterioration of the substrate and cool the inside of the projector.

[0007] However, if the supply of clean gas is stopped due to some abnormality, gas cannot be supplied to the projector, which poses a problem of an increase in temperature inside the projector.

[0008] An object of the present disclosure is to provide an air-cooling mechanism and a projector that are capable of taking in gas even if an abnormality occurs in the gas supply. [Means for solving the problem]

[0009] The air-cooling mechanism according to the present disclosure has an air intake port and a fan, and is attached to a first housing that draws gas into the first housing through the air intake port using the fan. The air-cooling mechanism includes a second housing having a first opening, a second opening, and a third opening, and a blower that causes gas to flow into the second housing through the first opening. The second opening of the second housing communicates with the air intake port of the first housing. The third opening communicates with the outside of the second housing.

[0010] The projector according to the present disclosure includes the above-described air-cooling mechanism. Effect of the Invention

[0011] The present disclosure can provide an air-cooling mechanism and a projector that are capable of taking in gas even if an abnormality occurs in the gas supply. [Brief description of the drawings]

[0012] [Figure 1] FIG. 1 is an external perspective view of a projector to which an air-cooling mechanism according to a first embodiment is attached; [Diagram 2] FIG. 1 is a plan view showing a configuration of a projector equipped with an air-cooling mechanism according to a first embodiment; [Diagram 3] A perspective view of a projection lens unit [Figure 4] FIG. 1 is a perspective view showing a configuration of an optical modulation element and liquid cooling. [Diagram 5] An explanatory diagram showing the configuration of a liquid cooling system. [Figure 6]FIG. 13 is an explanatory diagram illustrating a state of the adjustment mechanism when gas is supplied from the blower to the housing. [Figure 7] FIG. 13 is an explanatory diagram illustrating a state of the adjustment mechanism when gas is not being supplied to the housing from the blower; [Figure 8] A graph showing the change in the internal pressure of the housing over time and the change in the length of the coil spring [Figure 9] FIG. 9 is an explanatory diagram showing the state of the adjustment mechanism in state C2 of FIG. 8; [Figure 10] FIG. 9 is an explanatory diagram showing the state of the adjustment mechanism in state C3 of FIG. 8; [Figure 11] Graph showing temperature changes of internal components of a projector having an air-cooling mechanism without a third opening and an adjustment mechanism [Figure 12] Graph showing temperature changes of internal parts of a projector equipped with an air-cooling mechanism according to the first embodiment [Figure 13] FIG. 13 is an explanatory diagram showing a schematic configuration of an air-cooling mechanism according to a second embodiment. [Figure 14] FIG. 13 is an explanatory diagram showing a schematic configuration of an air-cooling mechanism according to a third embodiment. [Figure 15] FIG. 13 is an explanatory diagram showing a schematic configuration of an air-cooling mechanism according to a fourth embodiment. [Figure 16] FIG. 13 is an external perspective view of a projector equipped with an air-cooling mechanism according to a fifth embodiment. [Figure 17] FIG. 13 is a plan view showing a configuration of a projector equipped with an air-cooling mechanism according to a fifth embodiment. [Figure 18] FIG. 13 is a longitudinal sectional view of a heat exchanger according to a fifth embodiment. [Figure 19] FIG. 13 is an explanatory diagram for explaining the flow of gas inside a sealed housing of a projector according to a fifth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, the embodiments will be described in detail with reference to the drawings as appropriate. However, more detailed explanation than necessary may be omitted. For example, detailed explanation of already well-known matters or duplicate explanation of substantially the same configuration may be omitted. This is to avoid the following explanation becoming unnecessarily redundant and to facilitate understanding by those skilled in the art.

[0014] It should be noted that the accompanying drawings and the following description are provided to enable those skilled in the art to fully understand the present disclosure, and are not intended to limit the subject matter described in the claims.

[0015] (Embodiment 1) [1-1. Projector configuration] A projector 1 according to the first embodiment will be described with reference to Fig. 1. Fig. 1 is an external perspective view of the projector 1 according to the first embodiment. The projector 1 according to the first embodiment is, for example, a so-called three-chip DMD projector that uses three DMDs (Digital Micromirror Devices). Note that a liquid crystal element may be used instead of the DMD.

[0016] The projector 1 of the first embodiment includes a housing 2. The housing 2 has a substantially rectangular parallelepiped shape and includes a frame 12 that configures each side of the rectangular parallelepiped. The housing 2 further includes a top plate 3 and a bottom plate 4, and four side plates 5, 6, 7, and 8 that face each other. The frame 12 supports the top plate 3, the bottom plate 4m, and the side plates 5 to 8, each of which is made of metal or resin, and the top plate 3, the bottom plate 4m, and the side plates 5 to 8 are fixed to the frame 12. The housing 2 may include the top plate 3, the bottom plate 4m, and the side plates 5 to 8, each of which is made of metal, and may be connected by welding without the frame 12. Image light is projected from the side plate 5. The side plate 5 and the side plate 6 face each other. The side plate 8 is connected to the side plates 5 and 6 via the frame 12, and an air intake 9 through which outside air flows into the housing 2 is arranged. Side plate 7 is connected to side plates 5 and 6 via frame 12, and is provided with exhaust port 10 through which gas within housing 2 flows out to the outside of housing 2. Air inlet 9 and exhaust port 10 each have a plurality of holes 11. Top plate 3 is detachably fastened to the four side plates 5 to 8.

[0017] Next, reference is made to Fig. 2. Fig. 2 is a plan view showing the configuration of the projector 1 in the embodiment with the top plate 3 removed.

[0018] The projector 1 includes a power supply board 13, a light source unit 15, a light modulation unit 17, a projection lens unit 19, a fan 23, and a fan 25. The power supply board 13, the light source unit 15, the light modulation unit 17, the projection lens unit 19, the fan 23, and the fan 25 are housed in a housing 2.

[0019] The power supply board 13 converts the power supplied from an external power supply via a cable 21 into DC and supplies the driving power for the projector 1. The power supply board 13 also controls the power supplied to the light source unit 15, thereby controlling the amount of light irradiated from the light source unit 15.

[0020] The power supply board 13 has an integrated circuit that can be realized by semiconductor elements, etc., and can be configured by, for example, a microcomputer, a CPU, an MPU, a GPU, a DSP, an FPGA, or an ASIC. Each of the power supply boards 13 realizes a predetermined function by reading data and programs stored in a built-in memory unit (not shown) and performing various arithmetic processing. The memory unit can be realized by, for example, a hard disk drive (HDD), an SSD, a RAM, a DRAM, a ferroelectric memory, a flash memory, a magnetic disk, or a combination of these.

[0021] The light source unit 15 includes, for example, a plurality of laser light sources and a phosphor wheel. For example, laser light in a blue wavelength range emitted from the plurality of laser light sources is branched and enters the phosphor wheel, where it is converted into laser light in a yellow wavelength range. The laser light in the yellow wavelength range and the laser light in the blue wavelength range are mixed to generate white light, which is emitted from the light source unit 15 to the light modulation unit 17 via a relay optical system. The relay optical system includes a plurality of lenses and mirrors, and guides the white light emitted from the light source unit 15 to the light modulation unit 17.

[0022] The light modulation unit 17 modulates the incident white light in accordance with an input video signal to generate video light, and emits this video light to the projection lens unit 19. The light modulation unit 17 emits colored light in accordance with an image signal synchronized with each color of light transmitted from a signal board included in the power supply board 13.

[0023] The light modulation element 17a may be, for example, a DMD that changes the angle of a micromirror to change the traveling direction of light, or a liquid crystal element. In the embodiment, an example of the DMD will be described as the light modulation element 17a.

[0024] The projection lens unit 19 includes a plurality of lenses 19a, 19b, and 19c, and a lens barrel 19d that supports each lens, and projects the image light incident from the light modulation unit 17 on a screen (not shown) in an enlarged manner. In the embodiment, the projection lens unit 19 is described as including three lenses for the sake of simplicity, but is not limited to this and may include more lenses. The arrangement direction of the plurality of lenses 19a, 19b, and 19c is defined as a first direction.

[0025] The signal board of the power supply board 13 drives and controls the angle of the micromirror of each light modulation element 17a to a first angle and a second angle in synchronization with the input image signal. The light reflected at the first angle is emitted as image light, and the light reflected at the second angle is absorbed as unwanted light.

[0026] Fan 23 draws in outside air through intake port 9 and sends it into housing 2. Fan 25 exhausts gas inside housing 2 to the outside through exhaust port 10. In the first embodiment, intake port 9, exhaust port 10, and fans 23 and 25 are arranged along the first direction in housing 2, but this is not limiting, and they may be arranged so as to intersect with the first direction, or may be arbitrarily arranged on any of side panels 5, 6, 7, and 8.

[0027] Please refer to Figures 2 and 3. Figure 3 is a perspective view of the projection lens unit 19. A cover member 37 is provided that surrounds the side surface of the tip of the lens barrel 19d on the projection side of the projection lens unit 19. The cover member 37 is connected to the bottom plate 4 and the side plate 5, and supports the tip of the lens barrel 19d on the projection side. The cover member 37 is connected to the side plate 5 via a cushioning material such as sponge.

[0028] The side plate 8 has an opening 8a on an extension of the projection direction of the barrel 19d of the projection lens unit 19. A transparent member 8b is disposed so as to cover the opening 8a from the inside of the side plate 8. The transparent member 8b is a colorless transparent member that transmits image light, and is, for example, a glass plate or a resin member. The transparent member 8b is disposed on an extension of the tip side of the barrel 19d of the projection lens unit 19, and the image light projected from the projection lens unit 19 passes through the transparent member 8b.

[0029] Please refer to Fig. 2, Fig. 4 and Fig. 5. Fig. 4 is a perspective view showing the configuration of the light modulation element 17a and liquid cooling. Fig. 5 is an explanatory diagram showing the configuration of the liquid cooling system 30. The liquid cooling system 30 includes a heat receiving section 31, an inflow pipe 43, an outflow pipe 45 and a radiator 47. The heat receiving section 31 includes a heat receiving plate 39 and a flow path section 41. The heat receiving section 31 absorbs heat from the light modulation section 17, and the heat receiving section 33 absorbs heat from the light source section 15. The heat receiving sections 31 and 33 are each a metal plate, for example a copper plate.

[0030] One surface of the heat receiving plate 39 is in contact with the rear surface of the optical modulator 17a via grease, and receives the driving heat of the optical modulator 17a. The other surface of the heat receiving plate 39 is in contact with the flow path portion 41, and the heat of the heat receiving plate 39 is dissipated to the flow path portion 41.

[0031] A coolant flows inside the flow path 41, and heat from the heat receiving plate 39 is transferred to the coolant in the flow path 41. The heat receiving section 31 includes an inflow pipe 43 through which the coolant flows into the flow path 41, and an outflow pipe 45 through which the coolant flows out from the heat receiving section 31. The coolant that flows in from the inflow pipe 43 absorbs heat from the optical modulation element 17a and increases in temperature. The heat receiving section 31 includes a built-in pump, and the coolant with an increased temperature flows out from the flow path 41 through the outflow pipe 45 and flows into the radiator 47. The coolant is cooled by the radiator 47, and the cooled coolant circulates back to the heat receiving section 31. Note that an air-cooling system may be used instead of the liquid cooling system 30 to cool the optical modulation element 17a.

[0032] [1-2. Air cooling mechanism] 1 and 2, the projector 1 includes an air-cooling mechanism 71 that supplies clean gas to the air intake 9. The air-cooling mechanism 71 includes a housing 73, a blower 75, a valve mechanism 77, and a tank 79.

[0033] The housing 73 is a member that is attached to the air intake 9 of the projector 1. The housing 73 has a first opening 81, a second opening 83, and a third opening 85. The first opening 81 is connected to the air blower 75 via a duct 87.

[0034] The second opening 83 is connected to the intake port 9 of the housing 2 of the projector 1, and the gas inside the housing 73 is drawn into the inside of the housing 2 of the projector 1 by the fan 23 of the projector 1 through the second opening 83 and the intake port 9.

[0035] The third opening 85 communicates with the outside of the housing 73, and is adjusted by the valve mechanism 77 to be in an open state or a closed state.

[0036] The blower 75 blows gas into the housing 73 through the first opening 81. The blower 75 is connected to the tank 79 via a duct 89, and supplies clean gas in the tank 79 to the housing 73. The blower 75 is, for example, an air pump or a fan.

[0037] Tank 79 stores, for example, a dry and clean gas and is, for example, an air tank or a gas cylinder.

[0038] Valve mechanism 77 as an adjustment mechanism will be described with reference to Figures 6 and 7. Figure 6 is an explanatory diagram illustrating the state of valve mechanism 77 when gas is supplied from blower 75 to housing 73. Figure 7 is an explanatory diagram illustrating the state of valve mechanism 77 when gas is not supplied from blower 75 to housing 73.

[0039] The valve mechanism 77 has a valve structure that opens and closes the third opening 85 in accordance with the magnitude of the internal pressure in the housing 73. The valve mechanism 77 has a lid 91 and a coil spring 93 as a biasing member.

[0040] The lid 91 is larger than the third opening 85 and covers the third opening 85 from the inside of the housing 73. One end of the coil spring 93 is connected to the lid 91, and the other end of the coil spring 93 is connected to a stay 95 that supports the coil spring 93. The stay 95 is, for example, U-shaped, and a central portion of the stay 95 is connected to the coil spring 93, and both ends of the stay 95 are fixed to the housing 73. The stay 95 may have a hole 95a in a part thereof.

[0041] Coil spring 93 biases lid 91 toward the inside of housing 73. The biasing force of coil spring 93 is smaller than the internal pressure in housing 73 when gas is being supplied to housing 73 from blower 75. Therefore, as shown in FIG. 6, when gas is being supplied to housing 73 from blower 75, the internal pressure in housing 73 is larger than the biasing force of coil spring 93, so that lid 91 is pressed against the wall of housing 73 to cover third opening 85.

[0042] On the other hand, when an abnormality occurs in blower 75 and gas is not being supplied from blower 75 to housing 73, as shown in Fig. 7, the internal pressure in housing 73 is smaller than the biasing force of coil spring 93, so that lid 91 is moved toward the inside of housing 73 by the biasing force of coil spring 93 and third opening 85 is opened. Therefore, gas outside housing 73 can flow into housing 73 through third opening 85. Outside air flows into housing 73 by fan 23 arranged in housing 2, and further flows into the inside of housing 2 through second opening 83 and intake port 9, so that components in housing 2 can be prevented from overheating.

[0043] In the first embodiment, the housing 73 is provided with only one third opening 85 and one valve mechanism 77, but the present invention is not limited to this, and two third openings 85 and two valve mechanisms 77 may be provided in the housing 73. The valve mechanism 77 may be a door-type valve structure that opens and closes around one end of the lid 91 as a rotation axis.

[0044] The relationship between the internal pressure of the housing 73 and the length of the coil spring 93 is shown with reference to Figures 8 to 12. Figure 8(a) is a graph showing the change over time in the internal pressure of the housing 73, and Figure 8(b) is a graph showing the change in the length of the coil spring 93. Figure 9 is an explanatory diagram showing the state of the valve mechanism 77 in state C2 of Figure 8. Figure 10 is an explanatory diagram showing the state of the valve mechanism 77 in state C3 of Figure 8.

[0045] State C1 in Fig. 8 indicates a state in which the flow rate of gas flowing from blower 75 into housing 73 is normal and the internal pressure within housing 73 is normal pressure P1, which is higher than atmospheric pressure. In this state C1, lid 91 contacts the inner surface of housing 73 as shown in Fig. 6, closing third opening 85. In state C1, the pressure within housing 73 is P1, and the length of coil spring 93 is L1. Furthermore, if the natural length of coil spring 93 is L0 and the spring constant of the coil spring is k, then P1>k×(L0-L1)...Equation (1) The relationship holds.

[0046] For example, when an abnormality occurs in the blower unit 75 at time t1, the flow rate of the gas flowing from the blower unit 75 into the housing 73 gradually decreases, and the internal pressure in the housing 73 gradually decreases. Eventually, at time t2, the internal pressure in the housing 73 reaches a state C2 with a pressure P2 equal to the biasing force of the coil spring 93. As shown in FIG. 9, in this state C2, the lid 91 is in a state just about to separate from the inner surface of the housing 73. When the pressure in the housing 73 in state C2 is P2, P2 = k×(L0 - L1) ··· Equation (2) the following relationship holds.

[0047] When the flow rate of the gas flowing from the blower unit 75 into the housing 73 further decreases and the internal pressure in the housing 73 further decreases, the internal pressure in the housing 73 becomes a state C3 that is smaller than the biasing force of the coil spring 93. As shown in FIG. 10, in this state C3, the lid 91 is in a state separated from the inner surface of the housing 73. For example, when the pressure in the housing 73 in state C3 at time t3 is P3 and the length of the coil spring 93 is L3, P3 < k×(L0 - L3) ··· Equation (3) the following relationship holds.

[0048] At time t4, when the flow rate of the gas flowing from the blower unit 75 into the housing 73 becomes zero and the internal pressure in the housing 73 becomes equal to the atmospheric pressure, it becomes a state C4 in which the third opening 85 is completely opened. As shown in FIG. 7, in this state C4, the lid 91 is in a state separated from the inner surface of the housing 73, and the length of the coil spring 93 becomes the natural length L0. In state C4, P4 = P0 ··· Equation (4) the following relationship holds.

[0049] The spring constant k is set so that the above-described equations (1) to (4) hold, based on, for example, the intake air volume of the fan 23 of the projector 1 and the gas supply amount of the blower unit 75.

[0050] Next, the effects of the third opening 85 and the air-cooling mechanism 71 will be described with reference to Fig. 11 and Fig. 12. Fig. 11 is a graph showing temperature changes of internal parts of a projector 1 having an air-cooling mechanism without the third opening 85 and the valve mechanism 77 as a comparative example. Fig. 12 is a graph showing temperature changes of internal parts of a projector 1 having the air-cooling mechanism 71 of the first embodiment. Note that the time axes in Figs. 11 and 12 indicate relative time.

[0051] 11, graph G1 indicates the pressure change inside the housing 73, and graph G2 indicates the temperature change of the components inside the housing 2 of the projector 1. In the case of an air-cooling mechanism that does not have the third opening 85 and the valve mechanism 77, as shown in graph G1, when an abnormality occurs in the blower 75 and the pressure inside the housing 73 starts to drop, the fan 23 inside the housing 2 continues to draw gas into the housing 2, causing a negative pressure inside the housing 2. As a result, it becomes impossible to draw a sufficient amount of gas into the housing 2, so that the temperature inside the housing 2 gradually rises and eventually reaches an overheat state CH where an abnormality occurs in the components.

[0052] In contrast to this, the temperature change in the case of the air-cooling mechanism 71 having the third opening 85 and the valve mechanism 77 of the first embodiment will be described with reference to FIG. 12. In FIG. 12, graph G3 shows the pressure change in the housing 73, and graph G4 shows the temperature change of the components in the housing 2 of the projector 1. As shown in graph G3, when an abnormality occurs in the blower 75 and the pressure in the housing 73 starts to drop, the valve mechanism 77 opens the lid 91 to communicate the inside of the housing 73 with the outside, so that the pressure in the housing 73 becomes constant at atmospheric pressure P0. This allows the fan 23 in the housing 2 to continue to draw outside air into the housing 2. This reduces the rise in temperature in the housing 2, and prevents the components in the housing 2 from reaching an overheated state CH.

[0053] While the valve mechanism 77 opens the lid 91, outside air flows directly into the housing 2, which may cause the inflow of corrosive substances contained in the outside air, but when the user resolves the abnormality in the blower 75, clean gas is again supplied from the tank 79. Therefore, it is possible to prevent damage to components in the housing 2 due to heat while suppressing corrosion of the board.

[0054] [2. Effects, etc.] As described above, the air-cooling mechanism 71 of the first embodiment has the air intake 9 and the fan 23, and is attached to the housing 2 that draws gas into the inside through the air intake 9 by the fan 23. The air-cooling mechanism 71 includes the housing 73 having the first opening 81, the second opening 83, and the third opening 85, and the blower 75 that causes gas to flow into the housing 73 through the first opening 81. The second opening 83 of the housing 73 communicates with the air intake 9 of the housing 2. The third opening 85 communicates with the outside of the housing 73.

[0055] Air flows into housing 73 by blower 75, and can be made to flow into housing 2 via intake port 9. Even if an abnormality occurs in blower 75 and the supply of gas to housing 73 stops, outside air can be taken into housing 73 because third opening 85 communicates with the outside. Therefore, even if an abnormality occurs in blower 75, gas can be made to flow from housing 73 to housing 2.

[0056] The valve mechanism 77 is an adjustment mechanism that changes the flow rate of the gas flowing into the housing 73 from the third opening 85 according to the flow rate of the gas flowing from the blower 75 through the first opening 81. The valve mechanism 77 changes the flow rate of the gas flowing in from the third opening 85 according to the flow rate of the gas supplied from the blower 75. Since the flow rate of the gas supplied from the blower 75 has a positive correlation with the pressure of the gas, it can be said that the valve mechanism 77 changes the flow rate of the gas flowing in from the third opening 85 according to the pressure of the gas supplied from the blower 75. As a result, it is only necessary to increase the amount of gas flowing in from the third opening 85 only when the blowing capacity of the blower 75 is significantly reduced, so that the amount of gas containing corrosive particles flowing into the housing 73 can be reduced.

[0057] Furthermore, the valve mechanism 77 may allow gas outside the housing 73 to flow into the inside of the housing 2 through the third opening 85 when the flow of gas from the blower 75 into the housing 73 stops.

[0058] The valve mechanism 77 has a lid 91 that covers the third opening 85 from inside the housing 73, and a coil spring 93 that urges the lid 91 toward the inside of the housing 73. Since the valve mechanism 77 is a valve that opens and closes the lid 91 not by electrical control but by the pressure difference between the internal pressure and the external pressure of the housing 73, the valve mechanism 77 can operate even if the operation of the blower 75 is reduced or stopped due to an abnormality in the electrical system. This improves the reliability of the air-cooling mechanism 71 and the projector 1 that includes the same. Furthermore, since the valve mechanism 77 has a valve structure like a physical switch rather than being electrically controlled, the air-cooling mechanism 71 can be realized at low cost.

[0059] Also, a filter may be disposed in the third opening 85. When the lid 91 is open and outside air flows into the third opening 85, fine particles contained in the outside air can be removed by the filter. Since corrosive particles may adhere to the fine particles, it is possible to reduce the intrusion of the corrosive particles into the housing 2, and thus to reduce corrosion of the boards and components disposed in the housing 2.

[0060] Moreover, the blower 75 has a tank 79 that stores the gas to be supplied to the housing 73. This allows the gas stored in the tank 79 to be supplied to the housing 73.

[0061] (Embodiment 2) Next, air-cooling mechanism 71A in embodiment 2 will be described with reference to Fig. 13. Air-cooling mechanism 71 in embodiment 1 has valve mechanism 77, but air-cooling mechanism 71A in embodiment 2 has third opening 85 but does not have valve mechanism 77. Other than this and the points described below, air-cooling mechanism 71 in embodiment 1 and air-cooling mechanism 71A in embodiment 2 have the same configuration.

[0062] The third opening 85 is formed to have a size such that the internal pressure of the housing 73 becomes higher than atmospheric pressure when gas is being supplied from the blower 75. The air-cooling mechanism 71A does not have a valve mechanism 77, but since the blower 75 supplies clean gas from the tank 79 to the housing 73, gas flows out from the third opening 85 to the outside, but gas flows into the housing 2 through the second opening 83 and the intake port 9.

[0063] Even if an abnormality occurs in the blower section 75, outside air can be drawn into the housing 2 by the fan 23 of the projector 1 through the third opening 85 and the housing 73, so that, as in embodiment 1, the temperature of the components inside the housing 2 can be prevented from overheating.

[0064] (Embodiment 3) Next, air-cooling mechanism 71B according to the third embodiment will be described with reference to Fig. 14. Air-cooling mechanism 71B according to the third embodiment has a configuration in which a filter 97 is disposed in third opening 85 of air-cooling mechanism 71A according to the second embodiment. Apart from this point and the points described below, air-cooling mechanism 71B according to the third embodiment and air-cooling mechanism 71A according to the second embodiment have the same configuration.

[0065] Since the filter 97 is disposed in the third opening 85, in the event of an abnormality in the blower 75, fine particles contained in the outside air can be removed by the filter 97 when the outside air flows into the housing 73 from the third opening 85. This makes it possible to remove corrosive particles adhering to the fine particles in the outside air, thereby reducing the occurrence of corrosion within the housing 2.

[0066] (Embodiment 4) Next, air-cooling mechanism 71C according to the fourth embodiment will be described with reference to Fig. 15. Valve mechanism 77 of air-cooling mechanism 71 according to the first embodiment is a physical switch mechanism, but valve mechanism 77C of air-cooling mechanism 71C according to the fourth embodiment is configured by electrical control. Apart from this point and the points described below, air-cooling mechanism 71C according to the fourth embodiment and air-cooling mechanism 71 according to the first embodiment have the same configuration.

[0067] The valve mechanism 77C includes a sensor 99 for detecting the flow rate of gas flowing from the blower 75 into the housing 2, and an actuator 101 for adjusting the opening and closing of the lid 91 according to the detection value of the sensor 99. The actuator 101 can adjust the amount of movement of the lid 91 from the inner wall of the housing 73 by the amount of pushing out the rod, so that the amount of outside air taken into the housing 73 can be accurately adjusted. When the flow rate of gas detected by the sensor 99 is equal to or lower than a predetermined value, the actuator 101 operates to push out the rod, so that the lid 91 moves away from the inner surface of the housing 73 and moves into the housing 73. When the flow rate of gas detected by the sensor 99 is greater than the predetermined value, the actuator 101 houses the rod, so that the lid 91 is pressed against the inner surface of the housing 73. The sensor 99 may detect the pressure of the gas instead of the flow rate of the gas flowing from the blower 75. When the pressure of the gas detected by the sensor 99 is equal to or lower than a predetermined value, the actuator 101 operates to push out the rod, so that the lid 91 moves away from the inner surface of the housing 73 and moves into the housing 73. Therefore, the amount of outside air taken in can be adjusted according to the degree of abnormality in blower 75, and corrosion of the circuit boards inside housing 2 can be minimized.

[0068] (Embodiment 5) Next, a projector 1A according to embodiment 5 will be described with reference to Fig. 16 and Fig. 17. Projector 1A according to embodiment 4 has a sealed housing 2a structure inside housing 2. Other than this and the points described below, projector 1A according to embodiment 5 and projector 1A according to embodiment 1 have the same configuration.

[0069] In the fifth embodiment, a sealed space S1 and a non-sealed space S2 are arranged in the housing 2. The sealed space S1 is liquid-tight, so that no liquid flows in from the outside. Therefore, dust and dirt are prevented from flowing into the sealed space S1. The power supply board 13, the light source unit 15, the light modulation unit 17, and the projection lens unit 19 are arranged in the sealed space S1.

[0070] The projector 1A further includes a heat exchanger 22, and fans 23 and 25 are disposed within the space S2.

[0071] The fan 23 draws in outside air through the intake port 9 and sends it to the flow path F2 of the heat exchanger 22. The fan 25 exhausts the gas flowing out from the flow path F2 of the heat exchanger 22 to the outside through the exhaust port 10.

[0072] The sealed space S1 is a space surrounded by parts of the top plate 3, the bottom plate 4, the side plate 7, and the side plate 8, the side plate 5, and the partition wall 22a of the heat exchanger 22. The top plate 3, the bottom plate 4, the side plate 7, and the side plate 8, the side plate 5, and the partition wall 22a of the heat exchanger 22 form a sealed housing 2a. Sealing members such as packing are arranged between the frame 12 and the top plate 3 and the side plates 5, 7, and 8, and the top plate 3 and the side plates 5 to 8 are fixed to the frame 12 to maintain airtightness.

[0073] The sealed space S1 in the sealed housing 2a is divided into a first space Sp1, a second space Sp2, and a third space Sp3. The first space Sp1 and the second space Sp2 are divided by a partition wall 27. The third space Sp3 is a space inside the heat exchanger 22. The partition wall 27 is made of a metal or resin wall material. The lower end of the partition wall 27 is connected to the bottom plate 4, and the upper end of the partition wall 27 is connected to the top plate 3.

[0074] The power supply board 13 is disposed in the first space Sp1. A heat receiving portion 29 is disposed at the boundary between the first space Sp1 and the second space Sp2, and for example, the heat receiving portion 29 is provided on the partition wall 27. The gas in the first space Sp1 flows into the second space Sp2 through the heat receiving portion 29, and the heat receiving portion 29 absorbs heat of the gas flowing from the first space Sp1 to the second space Sp2. The heat receiving portion 29 is, for example, a radiator.

[0075] A projection lens unit 19, a light modulation section 17, and a light source section 15 are disposed in the second space Sp2.

[0076] The fan 35 is disposed between the light source unit 15 and the heat exchanger 22. The fan 35 draws in the gas in the second space Sp2 and causes the gas to flow into the flow path F1 of the heat exchanger 22.

[0077] The heat exchanger 22 includes a flow path F1 communicating with the sealed space S1 and a flow path F2 communicating with the space S2, and exchanges heat between the flow path F1 and the flow path F2. The flow path F1 and the flow path F2 are separated by a partition wall 22a. The partition wall 22a is a metal plate, for example, a thin aluminum plate. The flow path F1 has an intake port F1c communicating with the second space Sp2 via the fan 35, and an exhaust port F1d communicating with the first space Sp1. In the heat exchanger 22, as shown in FIG. 18, the flow path F1 and the flow path F2 have, for example, comb-shaped flow paths F1a and F2a that overlap each other alternately. The gas flowing through the flow path F1a, which is at a higher temperature than the outside air, is cooled by the outside air, which is at a relatively lower temperature, flowing through the flow path F2a by removing heat from the members arranged in the first space Sp1 and the second space Sp2. The cooled gas in the flow path F1a flows through the exhaust port F1d and again into the first space Sp1. The cross-sectional shapes of the flow paths F1a and F2a are not limited to rectangular but may be triangular. The heat exchanger 22 may have a configuration in which multiple fins protrude from the flow path F1 into the flow path F2, or may have a configuration in which heat is exchanged by heat pipes instead of the partition wall 22a and fins.

[0078] Refer to FIG. 19. In the unsealed space S2, radiators 49, 47, and 51 are arranged along the side plate 6. A liquid cooling system in which a refrigerant circulates between the radiator 49 and the heat receiving section 29 is configured in the same manner as the liquid cooling system 30, and the heat absorbed by the heat receiving section 29 is dissipated in the radiator 49 via the refrigerant. Also, a liquid cooling system in which a refrigerant circulates between the radiator 51 and the heat receiving section 33 is configured in the same manner as the liquid cooling system 30, and the heat absorbed by the heat receiving section 33 is dissipated in the radiator 51 via the refrigerant. By providing such a liquid cooling system, the projector 1A can reduce the amount of heat to be cooled by air cooling using the heat exchanger 22 by directly cooling the gas that has cooled the light source section 15, the light modulation section 17, and the power supply board 13, which are high-heat sources, with the gas outside the housing 2 via liquid cooling. This allows the size of the heat exchanger 22 to be reduced, and the projector 1A as a whole to be compact.

[0079] Next, the flow of gas in the sealed space S1 of the projector 1A in the first embodiment will be described with reference to Fig. 19. Fig. 19 is an explanatory diagram for explaining the flow of gas in the sealed housing 2a of the projector 1A. The gas flowing in the sealed space S1 is, for example, air.

[0080] The fan 23 draws gas in through the intake port 9 and flows into the flow path F2 of the heat exchanger 22. The gas flowing through the flow path F1 of the heat exchanger 22, which is the third space Sp3 of the sealed space S1, is cooled by the gas flowing through the flow path F2. The cooled gas flows into the first space Sp1 from the exhaust port F1d of the flow path F1 of the heat exchanger 22. The gas that flows into the first space Sp1 cools the power supply board 13. The gas heated by the power supply board 13 flows from the first space Sp1 to the second space Sp2 through the heat receiving portion 29. The heat receiving portion 29 absorbs heat from the gas passing through, so the gas is cooled again.

[0081] The cooled gas collides with side plate 5, changes its flow direction, flows through projection lens unit 19 along the surface of cover member 37, and cools lenses 19a to 19c of projection lens unit 19 via lens barrel 19d. Cover member 37 prevents gas from flowing on the projection side of lens 19c, making it possible to prevent the cooling air from causing fluctuations in the projected image light.

[0082] The gas that has cooled the projection lens unit 19 passes through the light modulation unit 17 to cool optical elements such as lenses and prisms. The gas that has cooled the light modulation unit 17 further passes through the light source unit 15 to cool optical elements such as a phosphor wheel and a collimator lens.

[0083] The gas that has cooled the light source unit 15 is caused to flow out to the intake port F1c of the flow path F1 of the heat exchanger 22 by the fan 35. In the heat exchanger 22, the gas that has been heated by passing through the sealed space S1 exchanges heat with the outside air. The outside air that has been heated as a result is exhausted to the outside from the flow path F2 of the heat exchanger 22 through the exhaust port 10 by the fan 25. In this way, the gas that has flowed out from the third space Sp3 of the heat exchanger 22 through the exhaust port F1d into the first space Sp1 passes through the power supply board 13, and further passes through the projection lens unit 19, the optical modulation unit 17, and the light source unit 15 in the second space Sp2, and flows into the third space Sp3 through the intake port F1c of the heat exchanger 22, thereby circulating and flowing in the sealed space S1 in order, and the sealed space S1 can be efficiently cooled. In this way, the gas flow path in the sealed space S1 is connected in one loop from the exhaust port F1d to the intake port F1c of the heat exchanger 22, and the objects to be cooled are arranged in order on the flow path, thereby minimizing the flow path required in the sealed space S1. It is possible to omit the space for airflow other than the place where the heat exchanger 22 is arranged, and it is possible to reduce wasted space, thereby realizing the miniaturization of the housing 2.

[0084] In addition, since the cover member 37, which covers at least a portion of the periphery of the lens 19c on the most projection side of the projection lens unit 19, is connected to the sealed housing 2a, it is possible to reduce the flow of gas within the sealed housing 2a to the projection side of the lens 19c on the most projection side of the projection lens unit 19, thereby reducing the occurrence of fluctuations in the projected image light.

[0085] Furthermore, the gas cooled by the heat exchanger 22 flows from the heat exchanger 22 into the power supply board 13. The gas that has passed through the power supply board 13 flows into the projection lens unit 19 from a first direction intersecting with the arrangement direction of the lenses 19a to 19c in the projection lens unit 19. The gas that has passed through the projection lens unit 19 flows into the heat exchanger 22. The cover member 37 extends in a direction intersecting with the first direction.

[0086] Since the cover member 37 extends in a direction intersecting with a first direction intersecting with the arrangement direction of the lenses 19a to 19c in the projection lens unit 19, the gas flows along the cover member 37. This makes it possible to reduce gas from getting around the lens 19c on the projection side of the projection lens unit 19, thereby reducing the occurrence of fluctuations in the projected image and the appearance of dust.

[0087] Furthermore, the projector 1A includes heat receiving sections 29, 31, and 33 arranged inside the sealed space S1, and radiators 47, 49, and 51 arranged outside the sealed space S1 and dissipating heat absorbed by the heat receiving sections 29, 31, and 33. The heat receiving sections 29, 31, and 33 exchange heat with the radiators 49, 47, and 51, respectively, via liquid. This can further improve the cooling effect inside the sealed space S1.

[0088] Furthermore, the power supply board 13 is disposed in the first space Sp1, and the projection lens unit 19, the light modulation section 17, and the light source section 15 are disposed in the second space Sp2. Since only the power supply board 13 is disposed in the first space Sp1, the cooling effect of the power supply board 13 can be improved by the gas cooled by the outside air.

[0089] Moreover, the heat receiving section 29 is disposed at the boundary between the first space Sp1 and the second space Sp2, and absorbs heat from the gas flowing from the first space Sp1 to the second space Sp2. This allows the gas heated by cooling the power supply board 13 to be cooled by the heat receiving section 29 when it flows from the first space Sp1 to the second space Sp2. The gas cooled again flows into the second space Sp2, thereby further improving the cooling effect of the projection lens unit 19, the light modulation section 17, and the light source section 15 disposed in the second space Sp2.

[0090] In this way, by forming an enclosed space S1 within the housing 2, the occurrence of corrosion in the power supply board 13, the light source unit 15, the light modulation unit 17, and the projection lens unit 19 can be further reduced through a synergistic effect with the air-cooling mechanism 71.

[0091] (Other embodiments) As described above, the embodiment has been described as an example of the technology in the present disclosure. For this purpose, the attached drawings and detailed description have been provided. Therefore, among the components described in the attached drawings and detailed description, not only components essential for solving the problem but also components that are not essential for solving the problem in order to exemplify the above technology may be included. Therefore, the fact that these non-essential components are described in the attached drawings or detailed description should not be used to immediately determine that these non-essential components are essential.

[0092] (1) In the above-described embodiment, the sealed space S1 is a liquid-tight space that suppresses the intrusion of dust and prevents liquid such as water from entering from the outside, but is not limited to this. The sealed space S1 may be an airtight space that blocks the inflow and outflow of gas from the outside. In this case, the gas in the sealed space S1 is not limited to air, and helium or argon may be used.

[0093] (2) In the above-described embodiment, the heat receiving portion 29 is disposed at the boundary between the first space Sp1 and the second space Sp2, but this is not limiting. The heat receiving portion 29 may be omitted.

[0094] (3) In the above-described embodiment, the cover member 37 surrounds the entire side surface of the tip of the projection side of the barrel 19d of the projection lens unit 19, but this is not limited thereto. The cover member 37 surrounds at least a portion of the side surface of the tip of the projection side of the barrel 19d of the projection lens unit 19, thereby making it possible to prevent gas from flowing into the tip side of the projection lens unit 19. The cover member 37 may be, for example, a wall standing up from the bottom plate 4 between the projection lens unit 19 and the heat receiving part 29, or may have an inverted L-shape, standing up from the bottom plate 4 and extending along the side plate 5 in a direction perpendicular to the arrangement direction of the multiple lenses 19a to 19c.

[0095] In addition, since the above-described embodiment is intended to illustrate the technology of the present disclosure, various modifications, substitutions, additions, omissions, etc. may be made within the scope of the claims or their equivalents. In addition, it is also possible to combine the components described in the above-described embodiment to create a new embodiment.

[0096] (Outline of the embodiment) (1) The air-cooling mechanism of the present disclosure has an intake port and a fan, and is attached to a first housing that draws gas into the first housing through the intake port using the fan. The air-cooling mechanism includes a second housing having a first opening, a second opening, and a third opening, and a blower that causes gas to flow into the second housing through the first opening. The second opening of the second housing communicates with the intake port of the first housing, and the third opening communicates with the outside of the second housing.

[0097] As a result, even if an abnormality occurs in the blower and the supply of gas to the second housing stops, outside air can be taken into the second housing because the third opening communicates with the outside. Therefore, even if an abnormality occurs in the blower, gas can flow from the second housing to the first housing.

[0098] (2) In the air-cooling mechanism of (1), a filter is disposed in the third opening.

[0099] (3) In the air-cooling mechanism of (1) or (2), an adjustment mechanism is provided that changes the flow rate of gas flowing into the second housing from the third opening in accordance with the flow rate of gas flowing in from the blower through the first opening.

[0100] (4) In the air-cooling mechanism of (3), when the flow of gas from the blower to the second housing stops, the adjustment mechanism allows gas outside the second housing to flow into the inside of the second housing through the third opening.

[0101] (5) In the air-cooling mechanism of (4), the adjustment mechanism has a lid that covers the third opening from inside the second housing, and a biasing member that biases the lid toward the inside of the second housing.

[0102] (6) In the air-cooling mechanism of (5), a filter is disposed in the third opening.

[0103] (7) In the air-cooling mechanism of (4), the adjustment mechanism has a lid that covers the third opening from inside the second housing, a sensor that detects gas flowing from the blower to the second housing, and an actuator that opens and closes the lid from the third opening depending on the detection value of the sensor.

[0104] (8) In the air-cooling mechanism according to any one of (1) to (7), the blower has a tank that stores the gas that is supplied to the second housing.

[0105] (9) In the air-cooling mechanism of any one of (1) to (8), the air-cooling mechanism is an air-cooling mechanism for a projector that is attached to a housing of a projector as the first housing.

[0106] (10) A projector equipped with any one of the air-cooling mechanisms (7) described in (1) to (9). [Industrial Applicability]

[0107] The present disclosure is applicable to air-cooling mechanisms that use gas as a refrigerant. [Explanation of symbols]

[0108] 1 Projector 2. Chassis 2a Sealed housing 3. Tabletop 4 Bottom plate 5, 6, 7, 8 Side panels 8a aperture 8b Transparent material 9 Air Intake 10 Exhaust port 11 holes 12 Frames 13 Power supply board 15 Light source section 17 Optical modulation section 19 Projection lens unit 19a, 19b, 19c Lenses 19d Telescope tube 21 Cable 22 Heat exchanger 22a Bulkhead 23, 25 Fan 27 Bulkhead 29, 31, 33 Heat receiving part 30 Liquid Cooling System 35 Fans 37 Cover material 39 Heat receiving plate 41 Flow path 43 Inflow pipe 45 Outflow pipe 47, 49, 51 Radiator 71 Air cooling mechanism 73 Case 75 Blower 77 Valve mechanism 79 Tank 81 First Opening 83 Second Opening 85 Third Opening 87, 89 Duct 91 Lid 93 Coil Spring 95 Stay 97 Filters 99 Sensors 101 Actuator F1, F2 flow paths F1a, F1b flow paths F1c air intake F1d exhaust port S1 Closed space S2 space Sp1 First Space Sp2 Second Space Sp3 The third space

Claims

1. An air-cooling mechanism attached to a first housing, the air-cooling mechanism having an air intake port and a fan, the air intake port being drawn into the first housing by the fan, the air-cooling mechanism comprising: The air cooling mechanism includes: a second housing having a first opening, a second opening, and a third opening; a blower that causes gas to flow into the second housing through the first opening, the second opening of the second housing communicates with the intake port of the first housing; The third opening communicates with the outside of the second housing. Air cooling mechanism.

2. A filter is disposed in the third opening. The air-cooling mechanism of claim 1 .

3. an adjustment mechanism that changes a flow rate of the gas flowing into the second housing from the third opening in accordance with a flow rate of the gas flowing from the blower through the first opening; The air-cooling mechanism of claim 1 .

4. When the flow of gas from the blower to the second housing is stopped, the adjustment mechanism allows gas outside the second housing to flow into the second housing through the third opening. The air-cooling mechanism according to claim 3.

5. The adjustment mechanism includes: a lid that covers the third opening from inside the second housing; and a biasing member that biases the lid toward the inside of the second housing. The air-cooling mechanism according to claim 4.

6. A filter is disposed in the third opening. The air-cooling mechanism according to claim 5.

7. The adjustment mechanism includes: a lid that covers the third opening from inside the second housing; a sensor for detecting gas flowing from the blower to the second housing; and an actuator that opens and closes the lid from the third opening in response to a detection value of the sensor. The air-cooling mechanism according to claim 4.

8. a tank for storing the gas to be supplied to the second housing by the blower; The air-cooling mechanism of claim 1 .

9. the air-cooling mechanism is an air-cooling mechanism for a projector that is attached to a housing of a projector as the first housing; The air-cooling mechanism of claim 1 .

10. The air-cooling mechanism according to any one of claims 1 to 9, projector.

Images