Cooling device and projector

Abstract

The present application provides a cooling device and a projector, which suppresses the large-scale of the device structure and efficiently cools a heat source. The cooling device of the present application comprises: a liquid cooling unit including: a heat exchanger which absorbs heat generated by a heat source through a liquid refrigerant; a pump which flows the liquid refrigerant; a tank which stores the liquid refrigerant; and a heat dissipation component which dissipates the liquid refrigerant; and a fan which makes cooling air flow through the heat dissipation component of the liquid cooling unit, and the cooling air flows in a space surrounded by constituent components of at least a part of the liquid cooling unit.

Description

Technical Field

[0001] This invention relates to a cooling device and a projector. Background Technology

[0002] In the projector disclosed in Patent Document 1 below, the heat generated by the light source unit is transferred to the refrigerant in a heat exchanger, and the refrigerant is circulated to a radiator located far from the light source unit via piping, and is discharged from a fan close to the radiator for heat dissipation.

[0003] Patent Document 1: Japanese Patent Application Publication No. 2023-032764

[0004] In the aforementioned projector, when the cooling unit components such as boxes and pumps are randomly arranged within the cooling airflow path towards the radiator in order to minimize the device structure, sufficient space for cooling airflow cannot be ensured, hindering the flow of cooling air and resulting in reduced cooling efficiency. However, when a dedicated duct is installed to efficiently guide the cooling air to the radiator, the device structure becomes larger. Summary of the Invention

[0005] To address the aforementioned issues, according to one aspect of the present invention, a cooling device is provided, comprising: a liquid cooling unit, the liquid cooling unit including: a heat exchanger that absorbs heat generated by a heat source through a liquid refrigerant; a pump that circulates the liquid refrigerant; a tank that stores the liquid refrigerant; a heat dissipation component that dissipates heat from the liquid refrigerant; and a fan that directs cooling air through the heat dissipation component of the liquid cooling unit, the cooling air circulating in a space surrounded by at least a portion of the constituent components of the liquid cooling unit.

[0006] According to one aspect of the present invention, a projector is provided having a cooling device and the heat source according to one aspect of the present invention. Attached Figure Description

[0007] Figure 1 This is a diagram showing the structure of the projector according to the first embodiment.

[0008] Figure 2 This is a schematic diagram of the light source unit.

[0009] Figure 3 This is a perspective view showing the structure of the cooling device.

[0010] Figure 4 This is a perspective view showing the structure of the cooling device according to the second embodiment.

[0011] Figure 5 This is a perspective view showing the structure of the cooling device according to the third embodiment.

[0012] Figure 6This is an exploded perspective view showing the main structural components of the liquid cooling unit according to the third embodiment.

[0013] Label Explanation

[0014] 1: Projector; 2: Light source unit (heat source); 3: Image forming unit; 4: Projection optical unit; 6, 106, 206: Cooling device; 60, 160, 260: Liquid cooling unit; 61: Heat exchanger; 61s: One end side (one end side of the heat exchanger); 62, 262: Pump; 63, 163, 263: Box; 64, 164: Heat dissipation component; 64s: One end side (one end side of the heat dissipation component); 67: Top cooling wall (first cooling wall); 68: Bottom cooling wall (second cooling wall); 70: Fan; 163s: One end side (one end side of the box); 262a: Pump section; 262b: Housing section; F: Cooling air; K: Space. Detailed Implementation

[0015] Hereinafter, an embodiment of the present invention will be described using the accompanying drawings.

[0016] In addition, in the following figures, the scale of the dimensions is sometimes different depending on the constituent elements so as to facilitate observation of each constituent element.

[0017] (First Implementation)

[0018] In this embodiment, the projector modulates the illumination light emitted from the light source unit to generate image light corresponding to the image information, and then magnifies and projects the generated image light onto a projection surface such as a screen. Figure 1 This is a diagram showing the structure of the projector according to this embodiment.

[0019] like Figure 1 As shown, the projector 1 of this embodiment includes a light source unit 2, an image forming unit 3, a projection optical unit 4, an outer casing 5, and a cooling device 6.

[0020] In the following description, the XYZ orthogonal coordinate system will be used as needed.

[0021] In the accompanying figures, the Y-axis is the direction of the image light projected by the projection optical unit 4, that is, the axis along the optical axis of the projection optical unit 4. The X-axis is orthogonal to the Y-axis and is the axis along the left-right direction of the screen SCR, which is the projection surface. The Z-axis is the axis orthogonal to both the X-axis and the Y-axis and is the axis along the up-down direction of the screen SCR.

[0022] In this embodiment, the direction along the Z-axis is referred to as the "up-down direction Z", +Z is referred to as the "upper side", -Z is referred to as the "lower side", the direction along the X-axis is referred to as the "left-right direction X", +X is referred to as the "right side", -X is referred to as the "left side", and the direction along the Y-axis is referred to as the "front-back direction Y", +Y is referred to as the "front side", and -Y is referred to as the "rear side".

[0023] Furthermore, the vertical direction Z, the horizontal direction X, and the front-back direction Y are merely names used to describe the configuration relationship of the various components of the projector 1, and do not specify the actual setting posture or direction of the projector 1.

[0024] The light source unit 2 provides white illumination light WL to the image forming unit 3. The detailed structure of the light source unit 2 will be described later.

[0025] The image forming unit 3 includes a color separation optical system 31, an optical modulation device 32R, an optical modulation device 32G, an optical modulation device 32B, and a synthesis optical system 34.

[0026] The color separation optical system 31 separates the illumination light WL from the light source unit 2 into red light LR, green light LG, and blue light LB, and guides them to the respective light modulation devices 32R, 32G, and 32B. The color separation optical system 31 includes a first dichroic mirror 311, a second dichroic mirror 312, a first reflecting mirror 313, a second reflecting mirror 314, a third reflecting mirror 315, a first relay lens 316, and a second relay lens 317.

[0027] The first dichroic mirror 311 allows red light LR to pass through and reflects green light LG and blue light LB. The second dichroic mirror 312 reflects the green light LG from the green light LG reflected by the first dichroic mirror 311 and allows blue light LB to pass through. The first reflecting mirror 313 reflects red light LR. The second reflecting mirror 314 and the third reflecting mirror 315 reflect blue light LB. The first relay lens 316 is disposed between the second dichroic mirror 312 and the second reflecting mirror 314, and the second relay lens 317 is disposed between the second reflecting mirror 314 and the third reflecting mirror 315. The first relay lens 316 and the second relay lens 317 are respectively disposed in the optical path of blue light BL to suppress the loss of blue light BL.

[0028] The light modulation device 32R consists of a liquid crystal panel that modulates red light LR according to image information to form an image. The light modulation device 32G consists of a liquid crystal panel that modulates green light LG according to image information to form an image. The light modulation device 32B consists of a liquid crystal panel that modulates blue light BL according to image information to form an image.

[0029] Field lenses 33R, 33G, and 33B are provided on the light incident side of each of the optical modulation devices 32R, 32G, and 32B. Additionally, although not shown in the diagram, an incident-side polarizer is disposed between each optical modulation device 32R, 32G, and 32B and each field lens 33R, 33G, and 33B, and an exit-side polarizer is disposed between each optical modulation device 32R, 32G, and 32B and the synthesizing optical system 34.

[0030] The synthesizing optical system 34 synthesizes the image light emitted from the light modulation devices 32R, 32G, and 32B respectively. The synthesizing optical system 34 is composed of a cross-shaped dichroic prism, which is approximately square when viewed from above, formed by bonding four right-angled prisms together. In the cross-shaped dichroic prism, a dielectric multilayer film is provided at the approximately X-shaped interface formed by bonding the right-angled prisms together.

[0031] The image light emitted from the synthetic optics system 34 is amplified by the projection optics unit 4 and projected onto the screen SCR. The projection optics unit 4 consists of multiple lenses.

[0032] Figure 2 This is a schematic diagram of the structure of light source unit 2.

[0033] like Figure 2 As shown, the light source unit 2 includes a light source 20, a telephoto optical system 21, a first phase difference plate 22a, a polarization separation element 23, a first focusing optical system 24, a wavelength conversion element 25, a second phase difference plate 22b, a second focusing optical system 26, a diffusion reflection element 27, an integrating optical system 28, a polarization conversion element 29, and an overlapping lens 30.

[0034] exist Figure 2 In this diagram, the central axis of the blue light BL emitted from the light source 20 is defined as the first optical axis ax1. The central axis of the illumination light WL emitted from the light source unit 2 is defined as the second optical axis ax2.

[0035] The light source 20, the telephoto optical system 21, the first phase retardation plate 22a, the polarization separation element 23, the second phase retardation plate 22b, the second focusing optical system 26, and the diffuse reflection element 27 are arranged sequentially on the first optical axis ax1. The wavelength conversion element 25, the first focusing optical system 24, the polarization separation element 23, the integrating optical system 28, the polarization conversion element 29, and the overlapping lens 30 are arranged sequentially on the second optical axis ax2. The first optical axis ax1 and the second optical axis ax2 are located in the same plane and are perpendicular to each other.

[0036] The light source 20 includes a plurality of light-emitting elements 20a. The plurality of light-emitting elements 20a are arranged in an array in a plane perpendicular to the first optical axis ax1. The light-emitting elements 20a are made of semiconductor lasers, for example, emitting blue light B in a first wavelength band corresponding to the blue wavelength band of 445nm to 465nm. Thus, the light source 20 emits blue light BL composed of the plurality of blue light rays B. That is, the light-emitting elements 20a emit blue light BL incident on the wavelength conversion element 25.

[0037] Blue light BL emitted from light source 20 is incident on telephoto optical system 21. Telephoto optical system 21 adjusts the beam diameter of blue light BL. In this embodiment, telephoto optical system 21 reduces the beam diameter of blue light BL. Telephoto optical system 21 is composed of convex lens 21a and concave lens 21b.

[0038] Blue light BL, passing through the telephoto optical system 21, is incident on the first retardation plate 22a. The first retardation plate 22a is, for example, a rotatable half-wavelength plate. The blue light BL emitted from the light source 20 is linearly polarized light with a predetermined polarization direction. By appropriately setting the rotation angle of the first retardation plate 22a, the blue light BL transmitted through the first retardation plate 22a can be converted into light containing S-polarized light components and P-polarized light components relative to the subsequent polarization separation element 23 in a predetermined ratio. Furthermore, by changing the rotation angle of the first retardation plate 22a, the ratio of the S-polarized light component to the P-polarized light component can be changed.

[0039] Blue light BL, containing both S-polarized and P-polarized components, generated by passing through the first phase difference plate 22a, is incident on the polarization separating element 23. The polarization separating element 23 is, for example, a wavelength-selective polarization beam splitter. The polarization separating element 23 is configured at 45° angles relative to the first optical axis ax1 and the second optical axis ax2, respectively.

[0040] The polarization separating element 23 has a polarization separation function that separates blue light BL into blue light BLs (S-polarized component) and blue light BLp (P-polarized component) relative to the polarization separating element 23. Specifically, the polarization separating element 23 reflects the blue light BLs (S-polarized component) and transmits the blue light BLp (P-polarized component). In addition, the polarization separating element 23 has a color separation function that allows fluorescent light YL (wavelength band different from blue light BL) to pass through, regardless of the polarization state.

[0041] Blue light BLs, an S-polarized beam emitted from polarization separating element 23, is incident on the first focusing optical system 24. The first focusing optical system 24 converges the blue light BLs toward wavelength conversion element 25. The first focusing optical system 24 is composed of convex lenses 24a and 24b. Furthermore, the number of lenses constituting the first focusing optical system 24 is not particularly limited. The blue light BLs emitted from the first focusing optical system 24 is incident on the wavelength conversion element 25 in a converged state.

[0042] The wavelength conversion element 25 has a wavelength conversion component 25a and a substrate 25b. The wavelength conversion component 25a contains phosphor particles that, when excited by blue light BLs, emit fluorescence YL in a second band different from the first band of the blue light BLs. The phosphor particles are made of materials such as yttrium aluminum garnet (YAG) based phosphors.

[0043] The second wavelength band of the fluorescent YL is, for example, the yellow band of 490 nm to 750 nm. The substrate 25b supports the wavelength conversion element 25a and functions as a heat dissipation element to release the heat of the wavelength conversion element 25a. According to this structure, the wavelength conversion element 25 generates and emits fluorescent YL by being excited by blue light BLs.

[0044] The fluorescence YL emitted from the wavelength conversion element 25 is parallelized by the first focusing optical system 24 and then incident on the polarization separation element 23. The fluorescence YL passes through the polarization separation element 23.

[0045] On the other hand, the blue light BLp of the P-polarized light emitted from the polarization separating element 23 is incident on the second phase retardation plate 22b. The second phase retardation plate 22b is disposed in the optical path between the polarization separating element 23 and the diffuse reflection element 27. The second phase retardation plate 22b is composed of a 1 / 4 wavelength plate. Therefore, the blue light BLp of the P-polarized light emitted from the polarization separating element 23 is converted into, for example, right-handed circularly polarized blue light BLc1 by the second phase retardation plate 22b and then incident on the second focusing optical system 26.

[0046] The second focusing optical system 26 is composed of convex lenses 26a and 26b. Furthermore, the number of lenses constituting the second focusing optical system 26 is not particularly limited. The second focusing optical system 26 causes blue light BLc1 to be incident on the diffuser / reflector element 27 in a convergent state.

[0047] The diffuse reflection element 27 is disposed on the opposite side of the light source 20 relative to the polarization separating element 23. The diffuse reflection element 27 causes the blue light BLc1 emitted from the second focusing optical system 26 to diffuse and reflect towards the polarization separating element 23. As the diffuse reflection element 27, it is preferable to use a diffuse reflection element that causes the blue light BLc1 to undergo Lambertian reflection without disturbing the polarization state.

[0048] Hereinafter, the light diffused and reflected by the diffuse reflection element 27 will be referred to as blue light BLc2. According to this embodiment, by diffuse reflection of blue light BLc1, blue light BLc2 with a substantially uniform illuminance distribution can be obtained. In addition, right-handed circularly polarized blue light BLc1 is reflected to become left-handed circularly polarized blue light BLc2.

[0049] After being converted into parallel light by the second focusing optical system 26, the blue light BLc2 is incident again on the second phase retardation plate 22b. At this time, the left-handed circularly polarized blue light BLc2 passes through the second phase retardation plate 22b and is converted into S-polarized blue light BLs1. The S-polarized blue light BLs1 is reflected by the polarization separating element 23 toward the integrating optical system 28.

[0050] Thus, the blue light BLs1, together with the fluorescent YL that has passed through the polarization separating element 23, is used as the illumination light WL. That is, the blue light BLs1 and the fluorescent YL are emitted from the polarization separating element 23 in the same direction as each other, generating a white illumination light WL that is a combination of the blue light BLs1 and the yellow fluorescent YL.

[0051] The illumination light WL is emitted toward the integrating optical system 28. The integrating optical system 28 is composed of a first lens array 28a and a second lens array 28b. The first lens array 28a and the second lens array 28b each have a structure in which multiple small lenses are arranged in an array.

[0052] The illumination light WL, which has passed through the integrating optical system 28, is incident on the polarization conversion element 29. The polarization conversion element 29 is composed of a polarization separation film and a phase difference plate. The polarization conversion element 29 converts the illumination light WL, which contains unpolarized fluorescent light YL, into linearly polarized light.

[0053] The illumination light WL, which has passed through the polarization conversion element 29, is incident on the overlapping lens 30. The overlapping lens 30, in cooperation with the integrating optics system 28, homogenizes the illuminance distribution of the illumination light WL in the illuminated area. In this way, the light source unit 2 generates the illumination light WL.

[0054] The outer casing 5 houses the light source unit 2, the image forming unit 3, and the cooling device 6, and constitutes the outer casing of the projector 1.

[0055] The projector 1 of this embodiment has a heat source disposed within the outer casing 5. Specifically, the heat source of the projector 1 is the light source unit 2.

[0056] The projector 1 of this embodiment includes a cooling device 6 for cooling the heat generated by the light source unit 2, which is a heat source.

[0057] Figure 3This is a perspective view showing the structure of the cooling device 6.

[0058] like Figure 3 As shown, the cooling device 6 includes a liquid cooling unit 60 and a fan 70. The liquid cooling unit 60 includes a heat exchanger 61, a pump 62, a housing 63, and a heat dissipation component 64 as constituent components.

[0059] The heat exchanger 61 absorbs heat generated by the light source unit (heat source) 2 through a liquid refrigerant. The liquid refrigerant is a heat exchange liquid that flows inside the heat exchanger 61. The heat exchanger 61 is a plate-shaped component with a cooling flow path formed between a plurality of fins 615 disposed inside the heat exchanger 61, through which the liquid refrigerant can flow. The heat exchanger 61 cools the light source unit 2 by transferring heat transferred to the plurality of fins 615 to the liquid refrigerant. The heat exchanger 61 has a heat exchange surface 610 supporting the light source unit 2 and a back surface 611 opposite to the heat exchange surface 610.

[0060] Pump 62 circulates the liquid refrigerant. Specifically, as described later, pump 62 supplies the low-temperature liquid refrigerant, cooled by heat dissipation component 64, to heat exchanger 61 via piping component 65. In this embodiment, pump 62 is, for example, a centrifugal pump.

[0061] The heat exchanger 61 also has an inlet section 612 for liquid refrigerant to flow in from the pump 62 via a piping assembly 65, and an outlet section 613 for the liquid refrigerant to flow out toward the tank 63. The inlet section 612 is located in the region of the heat exchange surface 610 of the heat exchanger 61 relative to the light source unit 2 on the -Y and +Z sides. Liquid refrigerant flows into the inlet section 612 from the outside. The inlet section 612 communicates with the internal space, and the liquid refrigerant flowing into the inlet section 612 flows between a plurality of fins 615 disposed inside, forming a cooling flow path. The plurality of fins 615 are at least arranged in the region overlapping with the light source 20, which is the object to be cooled, when viewed from above. The outlet section 613 is located in the region of the back surface 611 of the heat exchanger 61 relative to the light source unit 2 on the +Y and -Z sides. The outlet section 613 communicates with the internal space, allowing the liquid refrigerant flowing in the cooling flow path to flow out to the outside.

[0062] The container 63 stores liquid refrigerant. The container 63 primarily functions as a buffer to store replenishment refrigerant for use in replenishing liquid refrigerant lost due to evaporation within the refrigerant flow path. In this embodiment, the container 63 is made of metal and is integrally formed with the heat dissipation component 64. Alternatively, the container 63 may be separately constructed from the heat dissipation component 64.

[0063] The container 63 includes a first storage section 63a and a second storage section 63b. The first storage section 63a and the second storage section 63b are arranged sequentially from the -Z side to the +Z side in the vertical direction Z. Furthermore, since the first storage section 63a and the second storage section 63b are spaced apart from each other, the liquid refrigerant between the first storage section 63a and the second storage section 63b will not mix with each other.

[0064] The first storage section 63a is connected to the outlet section 613 of the heat exchanger 61, allowing liquid refrigerant from the heat exchanger 61 to flow into it. The liquid refrigerant flows from the heat exchanger 61 into the first storage section 63a and is supplied to the heat dissipation component 64. After being cooled by the heat dissipation component 64, the liquid refrigerant flows into the second storage section 63b, allowing it to circulate to the pump 62 via the piping component 80 (described later).

[0065] The heat dissipation component 64 is composed of a radiator for dissipating heat from the liquid refrigerant. The liquid refrigerant flows in or out between the heat dissipation component 64 and the heat exchanger 61 via the tank 63. The heat dissipation component 64 includes a first heat dissipation section 64a and a second heat dissipation section 64b.

[0066] The first heat dissipation section 64a has a plurality of plate-shaped first heat dissipation components 640 extending in the front-rear direction Y and arranged in the vertical direction Z. The first heat dissipation section 64a facilitates heat exchange between the cooling airflow F passing through it and the liquid refrigerant by allowing liquid refrigerant flowing from the first storage section 63a of the housing 63 to circulate from the +Y side to the -Y side in the cooling flow path within each of the first heat dissipation components 640. As a result, the first heat dissipation section 64a lowers the temperature of the liquid refrigerant flowing within the plurality of first heat dissipation components 640.

[0067] The liquid refrigerant cooled by the first heat dissipation section 64a flows into the second heat dissipation section 64b. Like the first heat dissipation section 64a, the second heat dissipation section 64b has a plurality of plate-shaped second heat dissipation components 641 extending in the front-rear direction Y and arranged in the vertical direction Z. The second heat dissipation section 64b allows the liquid refrigerant flowing from the first heat dissipation section 64a to circulate from the -Y side to the +Y side in cooling flow paths formed within each of the second heat dissipation components 641, thereby allowing heat exchange between the cooling airflow F passing through the second heat dissipation section 64b and the liquid refrigerant. Thus, the second heat dissipation section 64b dissipates heat from the liquid refrigerant flowing within each of the second heat dissipation components 641.

[0068] After being cooled by the second heat dissipation section 64b, the liquid refrigerant flows into the second storage section 63b of the housing 63. The second storage section 63b discharges the liquid refrigerant to the pump 62 via the piping assembly 80. The piping assembly 80 is positioned below the liquid surface of the liquid refrigerant stored in the second storage section 63b in the vertical direction (lower side of the vertical direction Z - Z). With this structure, air bubbles are less likely to enter the liquid refrigerant delivered to the pump 62 via the piping assembly 80, thus suppressing malfunctions caused by air mixing into the pump 62.

[0069] Piping assembly 80 is directly connected to pump 62 without communicating with the cooling flow path within heat exchanger 61. Therefore, the liquid refrigerant flowing within piping assembly 80 is supplied to pump 62 without mixing with the liquid refrigerant flowing within heat exchanger 61.

[0070] Fan 70 is an exhaust fan that directs cooling air F through the heat dissipation component 64 of the liquid cooling unit 60. In this embodiment, fan 70 is an axial fan, but the type of fan is not limited to this; centrifugal fans or Sirocco fans can also be used.

[0071] In this embodiment, the cooling device 6 arranges its constituent components in such a way that the cooling air F generated by the fan 70 circulates within a generally cubic space K. The space K through which the cooling air generated by the fan 70 circulates is divided by at least a portion of the constituent components of the liquid cooling unit 60. Specifically, the heat exchanger 61 is arranged along the YZ plane (first plane). The heat dissipation component 64 is arranged opposite the heat exchanger 61 along the YZ plane. That is, the plate-shaped heat exchanger 61 and the heat dissipation component 64 are arranged such that their respective thickness directions are aligned with the X direction. Therefore, the heat exchanger 61 covers the space K from the left side (-X) in the left-right direction X, and the heat dissipation component 64 covers the space K from the right side (+X) in the left-right direction X.

[0072] The box 63 is arranged along the XZ plane (second plane) that intersects the YZ plane. That is, the plate-shaped box 63 is arranged with its thickness direction aligned with the Y direction. Furthermore, the box 63 is connected to one end 61s of the heat exchanger 61 (+Y direction) and one end 64s of the heat dissipation component 64 (+Y direction). Therefore, the box 63 covers the space K from the front (+Y) side in the front-rear direction Y. In this embodiment, the box 63 is connected in close contact with one end 61s of the heat exchanger 61 and one end 64s of the heat dissipation component 64.

[0073] The liquid cooling unit 60 in this embodiment also includes a top cooling wall (first cooling wall) 67 and a bottom cooling wall (second cooling wall) 68.

[0074] The top cooling wall 67 is arranged along the XY plane (the third plane) that intersects the YZ plane and the XZ plane respectively, covering the upper (+Z) end face of the heat exchanger 61, the housing 63, the heat dissipation component 64, and the fan 70. Figure 3 In order to make it easier to observe the accompanying drawings, the top cooling wall 67 is shown in a state where it is separated from the upper side (+Z). However, in the liquid cooling unit 60 of this embodiment, the top cooling wall 67 covers the space K in a state where it is in close contact with one end of each component.

[0075] The bottom cooling wall 68 is arranged along the XY plane and covers the lower (-Z) side, i.e., the other end face, of the heat exchanger 61, the housing 63, the heat dissipation component 64, and the fan 70. In this embodiment, the bottom cooling wall 68 covers the space K in a state of being in close contact with the other end face of each component.

[0076] Thus, the heat exchanger 61, the housing 63, the heat dissipation component 64, the fan 70, the top cooling wall 67, and the bottom cooling wall 68, which are components of the liquid cooling unit 60, are arranged to surround the space K from different directions. That is, in the cooling device 6 of this embodiment, the top cooling wall 67 and the bottom cooling wall 68 surround the space K in the vertical direction Z, thereby further improving the airtightness of the space K. Therefore, it is possible to suppress the leakage of cooling air F from the space K.

[0077] In the liquid cooling unit 60 of this embodiment, each component is arranged such that the space K is open in one direction, namely the rear side (-Y). Furthermore, the cooling device 6 of this embodiment has a fan 70 arranged on the rear side (-Y) corresponding to the opening that opens the space K.

[0078] The fan 70 is positioned opposite the housing 63 of the liquid cooling unit 60 and surrounds the space K along the XZ plane. The fan 70, which is an axial fan, is positioned so that the rotation axis of the impeller is aligned with the Y direction.

[0079] In other words, in the cooling device 6 of this embodiment, the heat exchanger 61, the box 63, the heat dissipation component 64 and the fan 70 are configured to surround the space K from four different directions.

[0080] In the cooling device 6 of this embodiment, when the fan 70 rotates, the air in the space K is exhausted to the outside, and the space K becomes a negative pressure state. As a result, the cooling device 6 generates a flow of cooling air F from the outside of the heat dissipation component 64 through the inner space K toward the fan 70. The heat dissipation component 64 is cooled by the cooling air F.

[0081] The cooling air F passing through the heat dissipation component 64 flows along the surface of the housing 63, collides with the back surface 611 of the heat exchanger 61 opposite the heat dissipation component 64, and changes direction towards the fan 70, being discharged outwards from the space K. The cooling air F discharged from the fan 70 passes through the space K... Figure 1 The exhaust port 5a of the outer casing 5 shown discharges to the outside of the projector 1.

[0082] Thus, the cooling device 6 of this embodiment has a liquid cooling unit 60 and a fan 70. The liquid cooling unit 60 includes: a heat exchanger 61 that absorbs heat generated by the light source unit 2, which is a heat source, through a liquid refrigerant; a pump 62 that circulates the liquid refrigerant; a tank 63 that stores the liquid refrigerant; and a heat dissipation component 64 that dissipates heat from the liquid refrigerant. The fan 70 directs cooling air F through the heat dissipation component 64 of the liquid cooling unit 60. The cooling air F circulates in a space K surrounded by at least a portion of the constituent components of the liquid cooling unit 60.

[0083] According to the cooling device 6 of this embodiment, the space K surrounded by the components of the liquid cooling unit 60 from five different directions functions as a conduit forming a flow path for the cooling air F passing through the heat dissipation member 64. Therefore, compared to the case where additional conduits are provided, the device structure can be miniaturized. Furthermore, since none of the components of the liquid cooling unit 60 are positioned in the space K to obstruct the flow of the cooling air F, the cooling air F passing through the heat dissipation member 64 flows smoothly through the space K and is discharged. Therefore, the cooling efficiency of the heat dissipation member 64 can be improved.

[0084] Therefore, the cooling device 6 of this embodiment can efficiently cool the heat dissipation component 64 without the need for pipes, thus providing a cooling device that can suppress the enlargement of the device structure and efficiently cool the light source unit 2, which is a heat source.

[0085] The projector 1 according to this embodiment is equipped with a cooling device 6 that suppresses the enlargement of the light source unit 2 and efficiently cools it, so it is possible to provide a small projector that suppresses the heating of the light source unit 2, which is a heat source.

[0086] Second Implementation Method

[0087] Next, the cooling device according to the second embodiment of the present invention will be described. The layout of the components of the liquid cooling unit in this embodiment differs from that in the cooling device 6 of the first embodiment. Therefore, the differences in the layout of the liquid cooling unit will be mainly described below, and common structures will be labeled with the same reference numerals, and detailed descriptions thereof will be omitted.

[0088] Figure 4 This is a perspective view showing the structure of the cooling device 106 of this embodiment.

[0089] like Figure 4As shown, the cooling device 106 of this embodiment includes a liquid cooling unit 160 and a fan 70. The liquid cooling unit 160 includes a heat exchanger 61, a pump 62, a housing 163, and a heat dissipation component 164 as constituent components. Furthermore, in Figure 4 In order to make it easier to observe the attached diagram, the top cooling wall 67 is omitted.

[0090] In the liquid cooling unit 160 of this embodiment, the housing 163 is arranged along the YZ plane (first plane) opposite the heat exchanger 61. When viewed from above in the left-right direction X, the housing 163 of this embodiment has the same size as the heat exchanger 61. The housing 163 and the heat exchanger 61 are arranged with their respective thickness directions aligned with the left-right direction X. Specifically, the housing 163 covers the space K from the right side (+X) of the left-right direction X, and the heat exchanger 61 covers the space K from the left side (-X) of the left-right direction X.

[0091] Furthermore, the heat dissipation component 164 is arranged along the XZ plane (second plane) intersecting the YZ plane. The heat dissipation component 164 is arranged such that its thickness direction is aligned with the front-rear direction Y. Additionally, the heat dissipation component 164 is connected to one end 61s of the heat exchanger 61 and one end 163s of the housing 163. Thus, the heat dissipation component 164 covers the space K from the front (+Y) side in the front-rear direction Y. In this embodiment, the heat dissipation component 164 is connected in close contact with one end 61s of the heat exchanger 61 and one end 163s of the housing 163.

[0092] In this embodiment, the liquid refrigerant does not flow into or out between the heat dissipation component 164 and the heat exchanger 61 via the tank 163. The heat dissipation component 164 includes a first heat dissipation section 164a and a second heat dissipation section 164b.

[0093] The first heat dissipation section 164a has a plurality of plate-shaped first heat dissipation components 640 extending in the left-right direction X and arranged in the up-down direction Z. The first heat dissipation section 164a allows liquid refrigerant flowing from the inlet 612 of the heat exchanger 61 to circulate from the -X side to the +X side in the cooling flow path within each of the first heat dissipation components 640, thereby allowing heat exchange between the cooling airflow F passing through the first heat dissipation section 164a and the liquid refrigerant. As a result, the first heat dissipation section 164a lowers the temperature of the liquid refrigerant flowing within the plurality of first heat dissipation components 640.

[0094] In the cooling device 106 of this embodiment, the liquid refrigerant cooled by the first heat dissipation section 164a flows into the second heat dissipation section 164b via the tank 163.

[0095] The housing 163 includes a first storage section 163a and a second storage section 163b. The first storage section 163a and the second storage section 163b are arranged sequentially from the -Z side to the +Z side in the vertical direction Z. The first storage section 163a and the second storage section 163b are connected via a cutout 165a provided at one end (the -Y side) of the partition member 165. Therefore, liquid refrigerant can flow from the first storage section 163a into the second storage section 163b via the cutout 165a.

[0096] The first storage section 163a is connected to the first heat dissipation section 164a of the heat dissipation component 164, allowing liquid refrigerant from the first heat dissipation section 164a to flow into it. The second storage section 163b allows the liquid refrigerant flowing from the first storage section 163a to flow into the second heat dissipation section 164b of the heat dissipation component 164.

[0097] Like the first heat dissipation section 164a, the second heat dissipation section 164b has a plurality of plate-shaped second heat dissipation components 641 extending in the left-right direction X and arranged in the up-down direction Z. The second heat dissipation section 164b allows liquid refrigerant flowing from the second storage section 163b of the housing 163 to circulate from the +X side to the -X side in cooling flow paths formed within each of the second heat dissipation components 641, thereby facilitating heat exchange between the cooling airflow F passing through the second heat dissipation section 164b and the liquid refrigerant. As a result, the second heat dissipation section 164b lowers the temperature of the liquid refrigerant flowing within the plurality of second heat dissipation components 641.

[0098] After being cooled by the second heat dissipation section 164b, the liquid refrigerant is discharged to the pump 62 via the piping assembly 81. The piping assembly 81 is positioned below the vertical direction (lower side of the vertical direction Z - Z) of the liquid refrigerant level stored in the connection section between the second heat dissipation section 164b and the piping assembly 81. With this structure, air bubbles are less likely to enter the liquid refrigerant delivered to the pump 62 via the piping assembly 81, thus suppressing malfunctions caused by air mixing into the pump 62.

[0099] Piping assembly 81 is directly connected to pump 62 without communicating with the cooling flow path within heat exchanger 61. Therefore, the liquid refrigerant flowing within piping assembly 81 is supplied to pump 62 without mixing with the liquid refrigerant flowing within heat exchanger 61.

[0100] Thus, in the liquid cooling unit 160 of this embodiment, the fan 70 is arranged along the XZ plane in a manner that faces the heat dissipation component 164 and surrounds the space K, and the box 163 is arranged along the YZ plane in a manner that faces the heat exchanger 61 and surrounds the space K.

[0101] In the cooling device 106 of this embodiment, when the fan 70 rotates, the air in the space K is discharged to the outside, and the space K becomes a negative pressure state. The cooling air F flowing from the outside of the heat dissipation component 164 through the inner space K toward the fan 70 can be used to cool the liquid refrigerant flowing in the heat dissipation component 164.

[0102] In the cooling device 106 of this embodiment, the space K surrounded by the constituent components of the liquid cooling unit 160 also functions as a conduit forming a flow path for the cooling air F from the heat dissipation member 164 to the fan 70. The liquid refrigerant flowing in the liquid cooling unit 160 can be cooled. Therefore, the cooling device 106 of this embodiment efficiently cools the heat dissipation member 164 without the need for conduits, thus suppressing the need for large-scale device structures and efficiently cooling the light source unit 2, which is a heat source. Furthermore, in this embodiment, the heat dissipation member 164 and the fan 70 are arranged in a straight line along the longitudinal direction Y, thus suppressing the driving force of the fan 70 and allowing the cooling air F to flow more smoothly. Therefore, the power consumption of the fan 70 can be reduced.

[0103] (Third implementation method)

[0104] Next, the cooling device according to the third embodiment of the present invention will be described. The layout of the components of the liquid cooling unit in this embodiment differs from that in the embodiments described above. Therefore, the differences in the layout of the liquid cooling unit will be mainly described below, and common structures will be labeled with the same reference numerals, with detailed descriptions omitted.

[0105] Figure 5 This is a perspective view showing the structure of the cooling device 206 of this embodiment.

[0106] like Figure 5 As shown, the cooling device 206 of this embodiment includes a liquid cooling unit 260 and a fan 70. The liquid cooling unit 260 comprises a heat exchanger 161, a pump 262, a housing 263, and a heat dissipation component 264 as its constituent components. Furthermore, in Figure 5 In order to make it easier to observe the attached drawings, the top cooling wall 67 and the bottom cooling wall 68 are omitted.

[0107] The heat exchanger 161 and the heat dissipation component 264 are arranged opposite each other along the YZ plane (first plane). The housing 263 is arranged along the XZ plane (second plane).

[0108] The box 263 is connected to one end 161s of the heat exchanger 161 (+Y) and one end 264s of the heat dissipation component 264 (+Y).

[0109] The housing 263 includes a first storage section 263a and a second storage section 263b. The first storage section 263a and the second storage section 263b are arranged sequentially from the +Z side to the -Z side in the vertical direction Z. Liquid refrigerant discharged from the heat exchanger 161 by the pump 262 flows into the first storage section 263a of the housing 263. The second storage section 263b of the housing 263 receives liquid refrigerant after it has been cooled by the heat dissipation component 264, and is connected to the inlet section 612 of the heat exchanger 161 via the piping component 82.

[0110] The +X side of the housing 263 is connected to one end 264s of the heat dissipation component 264 in a close contact state. On the other hand, the -X side of the housing 263 is connected to the inlet 612 of the heat exchanger 161 via the piping component 82, so a gap is provided between the -X side of the housing 263 and the heat exchanger 161.

[0111] Pump 262 and housing 263 are configured together to surround space K from the front side (+Y) in the front-rear direction Y.

[0112] The heat dissipation component 264 in this embodiment includes a first heat dissipation section 264a and a second heat dissipation section 264b. The first heat dissipation section 264a has a plurality of plate-shaped first heat dissipation components 640 extending in the front-rear direction Y and arranged in the vertical direction Z. The first heat dissipation section 264a allows liquid refrigerant flowing from the first storage section 263a of the housing 263 to flow from the +Y side to the -Y side in the cooling flow path within each of the first heat dissipation components 640, thereby allowing the cooling airflow F passing through the first heat dissipation section 264a to exchange heat with the liquid refrigerant. As a result, the first heat dissipation section 264a lowers the temperature of the liquid refrigerant flowing within the plurality of first heat dissipation components 640.

[0113] The liquid refrigerant cooled by the first heat dissipation section 264a flows into the second heat dissipation section 264b. Like the first heat dissipation section 264a, the second heat dissipation section 264b has a plurality of plate-shaped second heat dissipation components 641 extending in the front-rear direction Y and arranged in the vertical direction Z. The second heat dissipation section 264b allows the liquid refrigerant flowing from the first heat dissipation section 264a to circulate from the -Y side to the +Y side in cooling flow paths formed within each of the second heat dissipation components 641, thereby allowing heat exchange between the cooling airflow F passing through the second heat dissipation section 264b and the liquid refrigerant. Thus, the second heat dissipation section 264b dissipates heat from the liquid refrigerant flowing within each of the second heat dissipation components 641.

[0114] After being cooled by the second heat dissipation section 264b, the liquid refrigerant flows into the second storage section 263b of the casing 263. The second storage section 263b discharges liquid refrigerant to the inlet section 612 of the heat exchanger 161 via the piping assembly 82. The piping assembly 82 is positioned below the vertical surface of the liquid refrigerant stored in the second storage section 263b (below the vertical direction Z - Z). This structure makes it difficult for air bubbles to enter the liquid refrigerant transported to the heat exchanger 161 via the piping assembly 82, thus suppressing malfunctions caused by air mixing into the pump 262.

[0115] The fan 70 is arranged along the XZ plane in a manner that is opposite to the pump 262 and the housing 263 of the liquid cooling unit 260 and surrounds the space K.

[0116] In the cooling device 206 of this embodiment, the heat exchanger 161, pump 262 and box 263, heat dissipation component 264 and fan 70 are arranged to surround the space K from four different directions.

[0117] Figure 6 This is an exploded perspective view showing the main structural components of the liquid cooling unit 260.

[0118] like Figure 6 As shown, in the liquid cooling unit 260 of this embodiment, the pump 262 includes a pump section 262a and a housing section 262b. The pump section 262a is the part that functions as a pump body supplying liquid refrigerant flowing from the tank 263 to the heat exchanger 161. The pump section 262a has an inlet section 262a1 that protrudes from the rear side -Y in the forward-backward direction Y and allows liquid refrigerant to flow from the heat exchanger 161, and a outlet section 262a2 that protrudes from the right side +X in the left-right direction X and discharges liquid refrigerant from the tank 263.

[0119] The heat exchanger 161 of this embodiment has a pump connection portion 162 connected to the pump 262. The pump connection portion 162 has a cylindrical shape that receives the pump portion 262a and includes a discharge portion 162a connected to the inflow portion 262a1 of the pump portion 262a and a receiving groove 162b for receiving the discharge portion 262a2 of the pump portion 262a.

[0120] The housing portion 262b retains the pump portion 262a. For example... Figure 5 As shown, the housing portion 262b is arranged along the XZ plane to cover the gap between the casing 263 and the heat exchanger 161. Thus, the housing portion 262b of the pump 262 covers the gap between the casing 263 and the heat exchanger 161 from the front side (+Y) in the front-rear direction Y.

[0121] In the cooling device 206 of this embodiment, when the fan 70 rotates, the air in the space K is exhausted to the outside, and the space K becomes a negative pressure state. As a result, the cooling device 206 generates a flow of cooling air F from the outside of the heat dissipation component 264 through the inner space K toward the fan 70.

[0122] The cooling air F passing through the heat dissipation component 264 flows along the surface of the housing 263 and the pump 262, collides with the back 611 of the heat exchanger 161 opposite to the heat dissipation component 264 and changes direction towards the fan 70, and is discharged to the outside of the space K.

[0123] In the liquid cooling unit 260 of this embodiment, the housing portion 262b covers the gap between the housing 263 and the heat exchanger 161 at the front (+Y) side of the space K, thereby suppressing the leakage of cooling air F flowing in the space K from the gap between the housing 263 and the heat exchanger 161. Therefore, the flow of cooling air F discharged to the outside of the space K through the heat dissipation component 264 can be smoothly generated.

[0124] Thus, the cooling device 206 according to this embodiment, like the embodiment described above, can efficiently cool the heat dissipation component 264 without the need for pipes, thereby suppressing the enlargement of the device structure and efficiently cooling the light source unit 2, which is a heat source.

[0125] Furthermore, the technical scope of the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.

[0126] In the above embodiment, fan 70 is exemplified as an exhaust fan arranged to surround space K together with the components of liquid cooling units 60, 160, and 260. However, the cooling device of the present invention can also be structured as follows: an intake fan that directly delivers the intake air as cooling air F into space K is used as the fan. When using a fan configured as an intake fan, the intake fan can be arranged in front of heat dissipation components 64 and 164. The cooling air F drawn into space K is directly discharged from the exhaust port 5a of the outer housing 5.

[0127] This is a summary of the disclosure.

[0128] The following is a summary published in this note.

[0129] (Note 1)

[0130] A cooling device comprising: a liquid cooling unit, the liquid cooling unit including: a heat exchanger that absorbs heat generated by a heat source through a liquid refrigerant; a pump that circulates the liquid refrigerant; a tank that stores the liquid refrigerant; a heat dissipation component that dissipates heat from the liquid refrigerant; and a fan that directs cooling air through the heat dissipation component of the liquid cooling unit, the cooling air circulating in a space surrounded by at least a portion of the constituent components of the liquid cooling unit.

[0131] According to this cooling device structure, the space surrounded by at least a portion of the components of the liquid cooling unit functions as a conduit for forming a flow path for cooling air passing through the heat dissipation components. Therefore, compared to cases where additional conduits are provided, the device structure can be miniaturized. Furthermore, none of the components of the liquid cooling unit are positioned within the space to obstruct the flow of cooling air, allowing the cooling air passing through the heat dissipation components to flow smoothly through and be exhausted from the space. Thus, the cooling efficiency of the heat dissipation components can be improved.

[0132] Therefore, the cooling device of this structure can efficiently cool heat dissipation components without the need for pipes, thus providing a cooling device that can suppress the enlargement of the device structure and efficiently cool the heat source.

[0133] (Note 2)

[0134] According to the cooling device described in Appendix 1, the heat exchanger, the housing, the heat dissipation component, and the fan are arranged to surround the space from different directions.

[0135] Based on this structure, a space can be formed that is surrounded by a heat exchanger, a box, heat dissipation components, and a fan from four different directions, and functions as a flow path for cooling air.

[0136] (Note 3)

[0137] According to the cooling device described in Appendix 2, the heat exchanger is arranged along a first surface, the heat dissipation component is arranged along the first surface opposite to the heat exchanger, the housing is arranged along a second surface intersecting the first surface and connected to one end of the heat exchanger and one end of the heat dissipation component, and the fan is arranged along the second surface opposite to the housing and surrounding the space.

[0138] According to this structure, the cooling air passing through the heat dissipation components flows along the surface of the casing, collides with the heat exchanger opposite the heat dissipation components, changes direction towards the fan side, and is discharged to the outside of the space. Therefore, a good flow path for the cooling air can be formed.

[0139] (Note 4)

[0140] According to the cooling device described in Appendix 2, the heat exchanger is arranged along a first surface, the housing is arranged opposite the heat exchanger along the first surface, the heat dissipation component is arranged along a second surface intersecting the first surface and connected to one end of the heat exchanger and one end of the housing, and the fan is arranged opposite the heat dissipation component and surrounding the space along the second surface.

[0141] With this structure, the heat dissipation components and the fan are arranged in a straight line, which reduces the fan's driving force and allows for smoother airflow. Therefore, it reduces the fan's power consumption.

[0142] (Note 5)

[0143] According to Appendix 1, the cooling device, the heat exchanger, the pump and the housing, the heat dissipation components and the fan are arranged to surround the space from different directions.

[0144] Based on this structure, a space can be formed that is surrounded by a pump and housing, heat dissipation components, and a fan from four different directions, and functions as a flow path for cooling air.

[0145] (Note 6)

[0146] According to the cooling device described in Appendix 5, the pump includes a pump section and a housing section that holds the pump section, the heat exchanger is arranged along a first surface, the heat dissipation component is arranged along the first surface opposite to the heat exchanger, the housing is arranged along a second surface that intersects the first surface and is connected to one end of the heat dissipation component and one end of the heat exchanger, the housing section of the pump is arranged along the second surface to cover the gap between the housing and the heat exchanger, and the fan is arranged along the second surface opposite to the housing and the pump and to surround the space.

[0147] According to this structure, the housing covers the gap between the casing and the heat exchanger, thus preventing the cooling air flowing in the space from leaking out through the gap between the casing and the heat exchanger. Therefore, the flow of cooling air discharged to the outside of the space through the heat dissipation components can be smoothly generated.

[0148] (Note 7)

[0149] According to any one of Appendices 3, 4, and 6, the liquid cooling unit further includes: a first cooling wall disposed along a third surface that intersects the first surface and the second surface respectively, and covering one end face of the heat exchanger, the housing, the heat dissipation component, and the fan; and a second cooling wall disposed along the third surface, and covering the other end face of the heat exchanger, the housing, the heat dissipation component, and the fan.

[0150] According to this structure, since it includes a liquid cooling unit that also includes a first cooling wall and a second cooling wall, the orientation of the space surrounded by the components of the liquid cooling unit can be increased. As a result, the airtightness of the space is improved, thus suppressing the leakage of cooling air from the space and ensuring smooth airflow.

[0151] (Note 8)

[0152] A projector comprising: a cooling device as described in any one of Annexes 1-7; and the heat source.

[0153] The projector based on this structure is able to provide a small projector that suppresses heat generation from the heat source because it has a cooling device that suppresses the growth of the light source unit and efficiently cools it.

[0154] (Note 9)

[0155] According to Appendix 8, the projector includes: a light source unit; an image forming unit that modulates light emitted from the light source unit according to image information to generate image light; and a projection optics unit that projects the image light generated by the image forming unit, wherein the heat source is the light source unit.

[0156] Based on this structure, a small projector can be provided that suppresses the heating of the light source unit, which is a heat source.

Claims

1. A cooling device comprising: Liquid cooling unit, the liquid cooling unit comprising: A heat exchanger that absorbs heat generated by a heat source using a liquid refrigerant; A pump that causes the liquid refrigerant to flow; A container that stores the liquid refrigerant; and heat dissipation components that dissipate heat from the liquid refrigerant; and A fan that directs cooling airflow across the heat dissipation components of the liquid cooling unit. The cooling air circulates in a space surrounded by at least a portion of the components of the liquid cooling unit.

2. The cooling device according to claim 1, wherein, The heat exchanger, the enclosure, the heat dissipation components, and the fan are arranged to surround the space from different directions.

3. The cooling device according to claim 2, wherein, The heat exchanger is arranged along the first surface. The heat dissipation component is arranged along the first surface in a manner opposite to the heat exchanger. The casing is arranged along a second side that intersects with the first side, and is connected to one end of the heat exchanger and one end of the heat dissipation component. The fan is arranged along the second surface in a manner that is opposite to the housing and surrounds the space.

4. The cooling device according to claim 2, wherein, The heat exchanger is arranged along the first surface. The box is arranged along the first surface in a manner opposite to the heat exchanger. The heat dissipation component is arranged along a second surface that intersects with the first surface, and is connected to one end of the heat exchanger and one end of the casing. The fan is arranged along the second surface in a manner that is opposite to the heat dissipation component and surrounds the space.

5. The cooling device according to claim 1, wherein, The heat exchanger, the pump, the housing, the heat dissipation components, and the fan are arranged to surround the space from different directions.

6. The cooling device according to claim 5, wherein, The pump includes a pump section and a housing section that holds the pump section. The heat exchanger is arranged along the first surface. The heat dissipation component is arranged along the first surface in a manner opposite to the heat exchanger. The enclosure is positioned along a second side that intersects with the first side, and is connected to one end of the heat dissipation component and one end of the heat exchanger. The housing portion of the pump is configured along the second surface in a manner that covers the gap between the tank and the heat exchanger. The fan is configured along the second surface in a manner that is opposite to the housing and the pump and surrounds the space.

7. The cooling device according to any one of claims 3, 4, and 6, wherein, The liquid cooling unit further includes: A first cooling wall, arranged along a third surface intersecting the first and second surfaces respectively, and covering one end face of the heat exchanger, the housing, the heat dissipation components, and the fan; and A second cooling wall is arranged along the third surface and covers the other end face of the heat exchanger, the housing, the heat dissipation components, and the fan.

8. A projector comprising: The cooling device according to any one of claims 1-6; and The heat source.

9. The projector according to claim 8, wherein, The projector has: Light source unit; An image forming unit modulates light emitted from the light source unit according to image information to generate image light; and A projection optical unit that projects the image light generated by the image forming unit. The heat source is the light source unit.

Images