JP7757616B2 - Cooling device, light source device and projection device - Google Patents

Description

The present invention relates to a cooling device, a light source device, and a projection device.

Today, projection devices (projectors) are used to project image data stored on personal computer screens, video screens, memory cards, etc. onto a screen. These projection devices focus light emitted from a light source onto a micromirror display element called a DMD (Digital Micromirror Device) or an LCD panel, displaying a color image on the screen.

For example, Patent Document 1 discloses a cooling device (forced air-cooled comb-shaped heat sink) in which the fins, which are the object to be cooled, are arranged in a comb shape with their tips positioned downward. This cooling device has flow straightening members (louvers) on the fins, which are arranged on one side of a base that carries a heat-generating element. These flow straightening members are inclined at an angle of 10 to 45 degrees from the direction of the flow of the cooling fluid toward the base, and are evenly distributed in a row closer to the tips of the fins than the center of the cooling device's height.

Japanese Patent Application Laid-Open No. 2001-118972

However, in the cooling device of Patent Document 1, the base, which is the heat-generating part, is located at the upper end of the wall that forms the flow path. As a result, the heat conduction efficiency and heat dissipation efficiency are poor, and the cooling effect is limited.

The present invention aims to provide a cooling device, light source device, and projection device with improved cooling performance.

A cooling device according to one embodiment of the present invention comprises a heat dissipation member forming a flow path, a first heat-generating member and a second heat-generating member connected to the heat dissipation member within the flow path, a first straightening member provided within the flow path and guiding the cooling fluid flowing within the flow path to the first heat-generating member, a second straightening member providing the cooling fluid to the second heat-generating member, and a third heat-generating member provided upstream of the flow path relative to the first heat-generating member, wherein the length of the first straightening member provided upstream of the flow path is shorter than the length of the second straightening member provided downstream of the flow path.

The present invention provides a cooling device, light source device, and projection device with improved cooling performance.

FIG. 2 is a diagram showing functional circuit blocks of the projection device according to the embodiment of the present invention. FIG. 1 is a schematic plan view showing the internal structure of a projection device according to an embodiment of the present invention. 1 is a perspective view of a cooling device according to an embodiment of the present invention; FIG. 2 is a perspective view of a fin according to an embodiment of the present invention. 4 is a cross-sectional view of the cooling device shown in FIG. 3 taken along line VV according to an embodiment of the present invention.

The following describes an embodiment of the present invention. Figure 1 is a functional circuit block diagram of a projection device 10. The projection device control unit comprises a CPU including an image conversion unit 23 and a control unit 38, a front-end unit including an input/output interface 22, and a formatter unit including a display encoder 24 and a display driver 26. Image signals of various standards input from the input/output connector unit 21 are converted by the image conversion unit 23 via the input/output interface 22 and system bus SB to unify them into image signals of a predetermined format suitable for display, and then output to the display encoder 24.

The display encoder 24 also expands and stores the input image signal in the video RAM 25, generates a video signal from the contents of this video RAM 25, and outputs it to the display driver 26.

The display driver 26 drives the display element 51, which is a spatial light modulator (SOM), at an appropriate frame rate in response to the image signal output from the display encoder 24. The projection device 10 irradiates the display element 51 with a light beam emitted from the light source device 60 via a light-guiding optical system, thereby forming an optical image using the light reflected from the display element 51, and projects and displays the image on a projection target such as a screen (not shown) via the projection optical system 220 (see Figure 2). The movable lens group 235 of this projection optical system 220 can be driven by a lens motor 45 for zoom adjustment and focus adjustment.

The image compression/expansion unit 31 also performs a recording process in which it compresses the luminance and color difference signals of the image signal using processes such as ADCT and Huffman coding, and writes the data sequentially to a memory card 32, which is a removable recording medium. Furthermore, in playback mode, the image compression/expansion unit 31 reads image data recorded on the memory card 32, expands each individual piece of image data that makes up a series of moving images on a frame-by-frame basis, and outputs the expanded data to the display encoder 24 via the image conversion unit 23. Therefore, the image compression/expansion unit 31 can output moving images, etc., based on the image data stored on the memory card 32.

The control unit 38 controls the operation of each circuit within the projection device 10 and is composed of a CPU, ROM which permanently stores operating programs such as various settings, and RAM which is used as work memory.

The key/indicator unit 37 is composed of main keys and indicators provided on the housing. Operation signals from the key/indicator unit 37 are sent directly to the control unit 38. In addition, key operation signals from the remote controller are received by the Ir receiving unit 35, demodulated into code signals by the Ir processing unit 36, and output to the control unit 38.

The control unit 38 is connected to the audio processing unit 47 via the system bus SB. The audio processing unit 47 is equipped with a sound source circuit such as a PCM sound source, and in projection mode and playback mode, converts audio data into analog form and drives the speaker 48 to emit amplified sound.

The control unit 38 controls the light source control circuit 41. The light source control circuit 41 individually controls the operation of the excitation light irradiation device 70 (see Figure 2) of the light source device 60 and the timing of synchronization with the phosphor wheel 101, etc., so that light in the specified wavelength band required for image generation is emitted from the light source device 60.

The control unit 38 also causes the cooling fan drive control circuit 43 to detect temperatures using multiple temperature sensors provided in the light source device 60, etc., and controls the rotation speed of a cooling fan (not shown) inside the projection device 10 based on the results of this temperature detection. The control unit 38 also controls the cooling fan drive control circuit 43 to continue rotating the cooling fan using a timer or the like even after the projection device 10 main body is powered off, or to power off the projection device 10 main body based on the results of temperature detection by the temperature sensors.

Figure 2 is a schematic plan view showing the internal structure of the projection device 10. In the following description of the projection device 10, left and right refer to the left and right directions relative to the projection direction, and front and rear refer to the front and rear directions relative to the direction of travel of the light beam from the projection device 10 (towards the screen). The projection device 10 has a control circuit board 241 near the right panel 14. This control circuit board 241 includes a power supply circuit block, a light source control block, and the like. The projection device 10 also has a light source device 60 located approximately in the center of the housing of the projection device 10. The projection device 10 also has a light source side optical system 170 and a projection optical system 220 between the light source device 60 and the left panel 15.

The light source device 60 includes an excitation light irradiation device 70, a green light source device 80 (including the excitation light irradiation device 70 and the fluorescent wheel device 100) that is a light source of green wavelength band light, and a red light source device 120 that is a light source of red wavelength band light. The light source device 60 also has a light-guiding optical system 140 that guides the light of each color wavelength band. The light-guiding optical system 140 guides the light of each color wavelength band emitted from each device (the excitation light irradiation device 70, the green light source device 80, and the red light source device 120) to the light-source-side optical system 170.

The excitation light irradiation device 70 is located near the rear panel 13, approximately in the center of the housing of the projection device 10 in the left-right direction. The excitation light irradiation device 70 includes a light source group consisting of multiple blue laser diodes 71, which are semiconductor light-emitting elements arranged so that their optical axes are parallel to the rear panel 13; a reflection mirror group 75 that converts the optical axis of the light emitted from each blue laser diode 71 by 90 degrees toward the front panel 12; and a heat sink 920 located between the blue laser diodes 71 and the right panel 14.

The light source group is formed by arranging multiple blue laser diodes 71 in a matrix. In this embodiment, a total of six blue laser diodes 71 are arranged in a matrix of two rows and three columns when viewed from the side from the left panel 15, with the vertical direction in FIG. 2 being the rows and the direction perpendicular to the paper surface being the columns (details not shown).

A plurality of collimator lenses 73 are arranged on the optical axis of each blue laser diode 71 to convert the blue wavelength band light emitted from each blue laser diode 71 into parallel light to increase its directivity. The reflecting mirror group 75 is formed by integrating a plurality of reflecting mirrors arranged in a stepped pattern with the mirror base. The reflecting mirror group 75 reduces the beam of light emitted from the blue laser diode 71 in one direction and directs it toward the first dichroic mirror 141.

A blower 93 with a built-in fan is disposed between the heat sink 920 and the rear panel 13, and the blue laser diode 71 is cooled by a cooling device 90 (see Figure 3) that includes this blower 93 and the heat sink 920. Furthermore, a blower 93 is disposed between the reflective mirror group 75 and the rear panel 13, and this blower 93 cools the reflective mirror group 75 and other components.

The fluorescent wheel device 100 is disposed on the optical path of the excitation light emitted from the excitation light irradiation device 70, near the front panel 12. The fluorescent wheel device 100 includes a phosphor wheel 101, a motor 110, a condenser lens group 111, and a condenser lens 115.

The phosphor wheel 101 is positioned so that it is approximately parallel to the front panel 12, that is, so that it is perpendicular to the optical axis of the light emitted from the excitation light irradiation device 70. A motor 110 drives and rotates the phosphor wheel 101. A group of condensing lenses 111 condenses the excitation light emitted from the excitation light irradiation device 70 onto the phosphor wheel 101 and also condenses the fluorescent light emitted from the phosphor wheel 101 toward the rear panel 13. A condensing lens 115 condenses the fluorescent light emitted from the phosphor wheel 101 toward the front panel 12. A blower 93 is disposed on the front panel 12 side of the motor 110, and this blower 93 cools the fluorescent wheel device 100 and other components.

The phosphor wheel 101 is formed in an approximately disk shape. The central axis of the phosphor wheel 101 is fixed to the shaft portion of the motor 110. The base material of the phosphor wheel 101 can be formed from a metal such as copper or aluminum. The surface of the base material on the excitation light irradiation device 70 side is mirror-finished by silver deposition or the like. Near the outer periphery of the phosphor wheel 101, on the excitation light incident side, a fluorescent light-emitting region and a transmission region that emit green wavelength band light are arranged side by side in the circumferential direction. The fluorescent light-emitting region and transmission region are each formed in an arc shape at a predetermined angle.

The phosphor layer of the fluorescent emission region is formed on the mirror-finished surface of the phosphor wheel 101. When this phosphor layer is irradiated with blue wavelength band light emitted from the excitation light irradiation device 70, it emits green wavelength band light as fluorescent light toward the condenser lens group 111. The transmission region is formed, for example, by fitting a translucent transparent substrate into a notch formed on the outer periphery of the substrate of the phosphor wheel 101. When irradiated with blue wavelength band light emitted from the excitation light irradiation device 70, the transmission region transmits or diffuses the blue wavelength band light from the front side of the phosphor wheel 101 toward the condenser lens 115 on the back side.

The red light source device 120 is provided with a red light source 121 arranged so that its optical axis is parallel to that of the blue laser diode 71, and a group of condensing lenses 125 that condenses the light emitted from the red light source 121. The red light source 121 is a light-emitting diode, which is a semiconductor light-emitting element that emits light in the red wavelength band. The red light source device 120 is arranged so that the optical axis of the red wavelength band light emitted by the red light source device 120 intersects the optical axis of the green wavelength band light emitted from the phosphor wheel 101. The red light source device 120 also has a heat sink 920 on the right panel 14 side of the red light source 121. A blower 93 is arranged between the heat sink 920 and the front panel 12. The red light source 121 is cooled by a cooling device 90 (see Figure 3) that includes the blower 93 and heat sink 920.

The light-guiding optical system 140 is composed of dichroic mirrors (first dichroic mirror 141, second dichroic mirror 148), a reflecting mirror 145 that converts the optical axis of the light beams of each color wavelength band to the same optical axis, and focusing lenses 146, 147, and 149 that focus the light beams of each color wavelength band. Each component is described below.

The first dichroic mirror 141 is positioned between the reflecting mirror group 75 and the condenser lens group 111. The first dichroic mirror 141 reflects the green wavelength band light emitted from the phosphor wheel 101 side and guides it toward the condenser lens 149 side. The first dichroic mirror 141 also transmits blue wavelength band light and red wavelength band light. The red wavelength band light emitted by the red light source 121 transmits through the first dichroic mirror 141, and the green wavelength band light emitted by the phosphor wheel 101 is reflected by the first dichroic mirror 141, so that the red wavelength band light and the green wavelength band light follow the same optical path toward the left panel 15.

The blue wavelength band light reflected by the reflecting mirror 143 has its optical axis converted by 90 degrees toward the left panel 15. A condensing lens 146 is arranged on the left panel 15 side of the reflecting mirror 143. A reflecting mirror 145 is arranged further toward the left panel 15 from this condensing lens 146. The reflecting mirror 145 converts the optical axis of the blue wavelength band light, which has been guided by the reflecting mirror 143 and collected by the condensing lens 146, by 90 degrees toward the rear panel 13.

The condenser lens 147 is disposed on the rear panel 13 side of the reflecting mirror 145. The second dichroic mirror 148 is disposed on the left panel 15 side of the condenser lens 149, on the rear panel 13 side of the condenser lens 147. The second dichroic mirror 148 reflects green wavelength band light and red wavelength band light and transmits blue wavelength band light.

The blue wavelength band light focused by the focusing lens 147 passes through the second dichroic mirror 148 and is focused by the focusing lens 173 of the light source side optical system 170.

The condenser lens 149 is disposed on the left panel 15 side of the first dichroic mirror 141. The green wavelength band light and red wavelength band light guided by the first dichroic mirror 141 are incident on the condenser lens 149. The green wavelength band light and red wavelength band light that are incident on and condensed by the condenser lens 149 are reflected by the second dichroic mirror 148 and condensed by the condenser lens 173 of the light source side optical system 170. In this way, the blue wavelength band light, green wavelength band light, and red wavelength band light are guided to the light source side optical system 170.

The light source side optical system 170 is composed of a condenser lens 173, a light guide device 175, a condenser lens 178, an optical axis conversion mirror 181, a condenser lens 183, an irradiation mirror 185, a condenser lens 195, etc. In this embodiment, a light tunnel is used as the light guide device 175, but a microlens array may also be used. Note that the condenser lens 195 is also part of the projection optical system 220, as it outputs image light emitted from the display element 51, which is located on the rear panel 13 side of the condenser lens 195, toward the projection optical system 220.

The condenser lens 173 is positioned near the entrance of the light guide device 175 and condenses the light from the light source. The light in each color wavelength band condensed by the condenser lens 173 is emitted toward the light guide device 175.

The optical axis conversion mirror 181 is positioned behind the condenser lens 178, on the optical axis of the light guide device 175 on the rear panel 13 side. The light beam emitted from the light outlet of the light guide device 175 is condensed by the condenser lens 178, and then its optical axis is converted by the optical axis conversion mirror 181 toward the left panel 15 side.

The light beam reflected by the optical axis conversion mirror 181 is focused by the focusing lens 183 and then directed by the illumination mirror 185 through the condenser lens 195 to the display element 51 at a predetermined angle. In this embodiment, a DMD is used as the display element 51. The display element 51 is cooled by a heat sink 920 provided on the rear panel 13 side.

The light source light, a bundle of rays irradiated onto the image forming surface of the display element 51 by the light source side optical system 170, is reflected by the image forming surface of the display element 51 and projected as projection light onto the screen via the projection optical system 220. Here, the projection optical system 220 is composed of a condenser lens 195, a movable lens group 235, a fixed lens group 225, etc. The movable lens group 235 is configured to be movable by a lens motor. The movable lens group 235 and the fixed lens group 225 are built into a fixed lens barrel. Therefore, the fixed lens barrel equipped with the movable lens group 235 is a variable focus lens, and is configured to allow zoom adjustment and focus adjustment.

By configuring the projection device 10 in this manner, when the phosphor wheel 101 is rotated and light is emitted from the excitation light irradiation device 70 and the red light source device 120 at appropriate times, light in each of the blue, green, and red wavelength bands is incident on the display element 51 via the light-guiding optical system 140 and the light source-side optical system 170. Therefore, the DMD, which is the display element 51 of the projection device 10, displays light of each color in a time-division manner according to data, allowing a color image to be projected onto the screen.

Next, the cooling device 90 of this embodiment will be described using Figures 3 to 5. Figure 3 is a perspective view schematically showing the cooling device 90. The cooling device 90 includes a heat source-side heat transfer member 91, a heat sink 920, and an air blower 93 that sends air L (cooling fluid) to the heat sink 920. The heat sink 920 and air blower 93 provided near the excitation light irradiation device 70, red light source device 120, fluorescent wheel device 100, and display element 51 in the projection device 10 of Figure 2 can be configured similarly to the heat sink 920 and air blower 93 of the cooling device 90 of Figure 3. Note that cooling devices having a configuration similar to that of the cooling device 90 may be arranged corresponding to some or all of the excitation light irradiation device 70, red light source device 120, fluorescent wheel device 100, and display element 51.

The heat transfer member 91 and the heat sink 920 are connected by heat pipes 94 (first heat pipe 94A and second heat pipe 94B). When viewed from the heat sink 920 side, the heat pipes 94 are heat-generating members connected to the heat source side.

The heat transfer member 91 is formed in a roughly rectangular plate shape and has a linear groove 911 recessed in a concave arc shape on one side. Two grooves 911 are provided in parallel and can engage with the heat pipe 94, which is formed in a cylindrical rod shape. The grooves 911 can be connected by brazing the side of the heat pipe 94. The heat transfer member 91 is directly or indirectly thermally connected to the light source element (which in this embodiment includes the blue laser diode 71, red light source 121, and phosphor wheel 101), which is the heat source, by, for example, being fixed to a holder that holds the light source element.

The heat sink 920 has multiple fins 92 to which a first heat pipe 94A (first heat-generating member) and a second heat pipe 94B (second heat-generating member) are connected. The fins 92, which are heat dissipation members, are thermally connected to the light source element, which is a heat source, via the first heat pipe 94A and the second heat pipe 94B.

As shown in FIG. 4, the fin 92 is formed from a rectangular metal sheet approximately 0.3 mm thick, with an upper plate portion 922a and a lower plate portion 922b, each of which has opposite edges folded toward one side. The rectangular, flat body portion 921, which accounts for the majority of the fin 92, is provided with a circular through-hole 923 and a rectifying member 924. A first heat pipe 94A and a second heat pipe 94B are inserted into the through-hole 923 and secured by brazing. The rectifying member 924 is formed by cutting a portion of the inner region of the body portion 921 of the fin 92 and bending the cantilevered, short, plate-like tongue portion. The rectifying member 924 is positioned so that it protrudes in the same direction as the upper plate portion 922a and the lower plate portion 922b, at approximately the same height. The rectifying member 924 is formed as a long, rectangular flat plate protruding from the plate surface of the body portion 921. The upper plate portion 922a, the lower plate portion 922b, and the flow rectifying member 924 are arranged approximately perpendicular to the main body portion 921.

As shown in FIG. 5, the through holes 923 are provided at two locations in a direction parallel to the extension direction of the upper plate portion 922a and the lower plate portion 922b (the flow path axis P1 direction of the flow path P). Therefore, the first heat pipe 94A and the second heat pipe 94B are also arranged side by side at two locations in a direction parallel to the extension direction of the upper plate portion 922a and the lower plate portion 922b (the flow path axis P1 direction of the flow path P). The multiple fins 92 are arranged side by side in the plate thickness direction of the fins 92 (the depth direction in FIG. 5). The first heat pipe 94A and the second heat pipe 94B are commonly inserted through the through holes 923 of each fin 92, connecting the fins 92 to each other. 4 , the tip 922a1 of the upper plate portion 922a of each fin 92 abuts or is adjacent to the base end 922a2 (i.e., the end of the main body 921) of the upper plate portion 922a of the adjacent fin 92 (see the enlarged view of portion A in FIG. 3 ). The tip of the lower plate portion 922b of each fin 92 also abuts or is adjacent to the base end (i.e., the end of the main body 921) of the lower plate portion 922b of the adjacent fin 92 (details not shown). Furthermore, the tip of the rectifying member 924 also abuts or is adjacent to the base end of the rectifying member of the adjacent fin 92 (details not shown). Therefore, as shown in the cross-sectional view of FIG. 5 , the heat sink 920 is surrounded by the upper plate portion 922a, the lower plate portion 922b, and the opposing main body 921 of each fin 92 to form a flow path P, and is configured to include a cylindrical flow path P that opens in the direction of the flow path axis P1 of the flow path P. The heat sink 920 has multiple such flow paths P arranged in parallel in the longitudinal direction of the heat pipe 94.

The upstream first heat pipe 94A and downstream second heat pipe 94B shown in FIG. 5 are connected to fins 92 (heat dissipation members) on the inside of the width direction (vertical direction) within the flow path P. A rectifying member 924 is provided within the flow path P and guides air L (cooling fluid) flowing within the flow path P to the second heat pipe 94B. The rectifying member 924 is provided vertically below the first heat pipe 94A and the second heat pipe 94B and is arranged so as to slope upward as it approaches the downstream side along the flow path axis P1. In this embodiment, the rectifying member 924 is inclined at 45 degrees with respect to the flow path axis P1. The rectifying member 924 has a guide surface 924a that guides air L (cooling fluid) flowing from upstream in the flow path P upward. The rectifying member 924 is provided upstream of the second heat pipe 94B in the flow path P. A portion of the rectifying member 924 is located below the first heat pipe 94A. Another part of the rectifying member 924 is located below and between the first heat pipe 94A and the second heat pipe 94B.

The blower 93 has a case 931 and a fan 932. Note that the fan 932 is shown schematically in Figure 5. The blower 93 has air intakes 931a and 931b on the top and bottom surfaces of the case 931, and has a fan 932 inside corresponding to the air intakes 931a and 931b. In this embodiment, a sirocco fan is used as the fan 932. The upper air intakes 931a are provided intermittently at three locations around the axis of the fan 932 (see Figure 3). The lower air intake 931b is formed in a substantially circular shape. The air intakes 931a and 931b are located inside the outer diameter of the fan 932.

Here, the movement of air in the cooling device 90 will be described. When the fan 932 of the blower 93 is driven to rotate, negative pressure is generated such that air is drawn in through the air intakes 931a and 931b, and air is drawn in from outside the projection device 10 through air intakes (details not shown) provided at any location on the exterior case (including the front panel 12, rear panel 13, right panel 14, and left panel 15) of the projection device 10 shown in FIG. 2. The blower 93 draws in air drawn in from outside the projection device 10 through the air intakes 931a and 931b, and sends it toward the heat sink 920 using the fan 932.

Of the air L blown toward the heat sink 920, a portion of the air L1 entering from below passes below the rectifying member 924, while another portion of the air L1 is guided upward in the flow path P by the guide surface 924a of the rectifying member 924. Of the air L blown toward the heat sink 920, a portion of the air L2 entering from above hits the first heat pipe 94A and passes above the first heat pipe 94A, while another portion of the air L2 is blown to the first heat pipe 94A and passes below the first heat pipe 94A. Air L21 passing below the first heat pipe 94A is pushed up by a portion of the air L11 flowing below and guided upward by the rectifying member 924, and is guided to be blown to the second heat pipe 94B located downstream of the first heat pipe 94A.

In the example of Figure 5, air L21 is sent to the second heat pipe 94B and then passes above the second heat pipe 94B. Meanwhile, air L11 guided by the straightening member 924 is also pushed upward, sent to the second heat pipe 94B, and then passes below the second heat pipe 94B. After that, all of the air L passing through the flow path P is exhausted from the opening on the downstream side of the heat sink 920.

In the cooling device 90, heat transferred from the heat source side via the first heat pipe 94A and the second heat pipe 94B is transferred from the upper side of the fins 92 to the entire main body 921. Furthermore, because the first heat pipe 94A and the second heat pipe 94B are both connected above the fins 92, the upper side of the fins 92 is hotter than the lower side. Therefore, without the straightening member 924, the air L2 flowing upward is relatively slow, and the air L2 that has increased in temperature after passing near the first heat pipe 94A mainly flows into the second heat pipe 94B, reducing the heat dissipation efficiency around the second heat pipe 94B.

The heat pipes 94 (first heat pipe 94A and second heat pipe 94B) can also be installed at the widthwise center of the flow path P (the vertical center in Figure 5) relative to the fins 92. In this case, however, depending on the surrounding configuration in which the cooling device 90 is installed, it may be necessary to bend the heat pipes 94. However, each heat pipe 94 has a limited amount of heat it can transport, and bending it may reduce the amount of heat it can transport.

In this embodiment, the cooling device 90 includes a rectifying member 924 below the first heat pipe 94A and the second heat pipe 94B, which guides the relatively low-temperature air L1 flowing below toward the second heat pipe 94B while avoiding blowing it toward the first heat pipe 94A (see, for example, the flow path of air L11). This allows both the first heat pipe 94A and the second heat pipe 94B to be cooled by the low-temperature air. Even if the first heat pipe 94A or the second heat pipe 94B is connected to a biased position on one side of the fin 92 (the upper side in this embodiment) due to the surrounding structure of the cooling device 90, the rectifying member 924 guides the flow of air L within the flow path P, allowing the air L to flow at a high flow rate toward the second heat pipe 94B, which is the downstream heat-generating component, thereby efficiently cooling the second heat pipe 94B. Furthermore, in this embodiment, because the air intakes 931a and 931b are located above and below the blower 93, even if sufficient space cannot be secured above and below the cooling device 90, the flow path resistance on the intake side can be reduced and a decrease in intake capacity can be prevented. This improves cooling performance.

It is also possible to provide three or more through-holes 923, and three or more heat pipes 94 arranged in the through-holes 923. This allows heat to be transported to the heat sink 920 even when the heat source generates a large amount of heat. The three or more through-holes 923 and heat pipes 94 can be arranged in the direction of the cooling fluid flow. In this case, low-temperature air L is circulated through a portion of the flow path P, and the straightening member 924 can blow the low-temperature air L to any portion of the heat pipe 94, selectively cooling the area around a specific heat pipe 94.

Furthermore, when heat pipes 94 are provided in three or more locations, multiple rectifying members 924 may also be provided corresponding to the downstream heat pipes 94. In this case, the rectifying members 924 may be provided corresponding to each of the downstream heat pipes 94, or may be provided corresponding to some of them. Furthermore, when heat pipes 94 are provided in three or more locations and rectifying members 924 are provided in multiple locations, the length of the upstream rectifying member 924 may be shorter than the length of the downstream rectifying member 924. Furthermore, the rectifying members 924 may be provided along the flow path axis P1 direction, or may be provided in multiple stages (e.g., upper and lower stages) parallel to the flow path axis P1.

Furthermore, the fins 92, which are heat dissipation members, may be connected to other heat-generating members, such as solid rod-shaped members, rather than heat pipes 94, to allow for heat transfer from the heat source.

Furthermore, the rectifying member 924 is not limited to the configuration shown in this embodiment, and may be provided in other ways. For example, the rectifying member may be formed as a long, flat plate separate from the fins 92, and placed within the flow path P by commonly inserting it through slit-shaped openings provided in multiple fins 92.

Furthermore, the blower 93 may have a configuration different from that shown in this embodiment. For example, the fan 932 is not limited to a sirocco fan, and other fans such as an axial fan or a turbo fan can be applied. The air intakes 931a and 931b can be provided in any position and shape depending on the configuration of the fan.

As described above, the cooling device 90 of an embodiment of the present invention, as well as the light source device 60 and projection device 10 equipped with the cooling device 90, comprise a heat dissipation member (92) that forms a flow path P, a first heat-generating member (94A) and a second heat-generating member (94B) that are connected to the heat dissipation member (92) within the flow path P, and a rectifying member 924 that is provided within the flow path P and guides the cooling fluid (air L) flowing within the flow path P to the second heat-generating member (94B). This allows the rectifying member 924 to guide the air L within the flow path P to the high-temperature heat-generating portion, thereby improving the cooling function of the cooling device 90.

The first heat-generating element (94A) provided on the upstream side of the flow path P and the second heat-generating element (94B) provided on the downstream side of the flow path P are arranged side by side in the direction of the flow path axis P1 of the flow path P, and the flow straightening element 924 is provided below the first heat-generating element (94A) and the second heat-generating element (94B) and has a guide surface 924a that guides the cooling fluid (air L) flowing from upstream in the flow path P upward. As a result, the low-temperature air L1 flowing on the lower side can be guided to the high-temperature second heat-generating element (94B) on the downstream side, allowing for efficient cooling.

Furthermore, the cooling device 90 in which the straightening member 924 is disposed at an angle upstream of the second heat-generating member (94B) in the flow path P can guide the air L1 toward the second heat-generating member (94B) without significantly interfering with the flow of the air L1 guided by the straightening member 924.

Also described is a configuration in which a portion of the rectifying member 924 is located below the first heat generating member (94A), and another portion of the rectifying member 924 is located below and between the first heat generating member (94A) and the second heat generating member (94B). This allows the lower temperature air L1 from below to be blown toward the second heat generating member (94B) together with the air L21 that has circulated near the first heat generating member (94A), while avoiding being guided toward the first heat generating member (94A).

The heat dissipation member (92) is a fin 92 formed from a metal plate on which a rectifying member 924 is provided, and the rectifying member 924 is formed by bending a portion of the fin 92. This simplifies the construction of the fin 92 and the heat sink 920 that includes the rectifying member 924 in the flow path P.

We have also described a configuration that includes a heat sink 920 that includes a cylindrical flow path P that opens in the direction of the flow path axis P1 of the flow path P, with multiple fins 92 to which a first heat generating element (94A) and a second heat generating element (94B) are connected. The first heat generating element (94A) and the second heat generating element (94B) are heat pipes 94 that are connected to the heat source. This allows air L to circulate efficiently within the flow path P, and allows heat to be efficiently dissipated from the fins 92, which are cooling elements that surround the flow path P.

The above-described embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments may be embodied in a variety of other forms, and various omissions, substitutions, and modifications may be made without departing from the spirit of the invention. These embodiments and their variations are included within the scope and spirit of the invention, and are also included in the scope of the invention and its equivalents as set forth in the claims.

The invention described in the first claim of the present application is as follows:
[1] A heat dissipation member that forms a flow path;
a first heat generating member and a second heat generating member connected to the heat dissipation member within the flow path;
a flow straightening member provided in the flow path and guiding the cooling fluid flowing in the flow path to the second heat-generating member;
A cooling device comprising:
[2] The first heat generating member provided on the upstream side of the flow path and the second heat generating member provided on the downstream side of the flow path are arranged side by side in a flow path axial direction of the flow path,
the flow straightening member is provided below the first heat generating member and the second heat generating member, and has a guide surface that guides the cooling fluid flowing from upstream in the flow path upward.
The cooling device according to [1] above.
[3] The cooling device according to [1] or [2], wherein the straightening member is provided at an incline upstream of the second heat-generating member in the flow path.
[4] A part of the rectifying member is located below the first heat-generating member,
another part of the rectifying member is located below and between the first heat generating member and the second heat generating member;
The cooling device according to any one of [1] to [3] above,
[5] The heat dissipation member is a fin formed of a metal plate on which the rectifying member is provided,
The rectifying member is configured by bending a part of the fin.
The cooling device according to any one of [1] to [4] above,
[6] A heat sink including a cylindrical flow path that is open in a flow path axial direction of the flow path and includes a plurality of fins to which the first heat generating member and the second heat generating member are connected,
the first heat generating member and the second heat generating member are heat pipes connected to a heat source side;
The cooling device according to [5] above.
[7] The cooling device according to any one of [1] to [6],
a light source element that is a heat source thermally connected to the heat dissipation member;
A light source device comprising:
[8] The light source device according to [7] above,
a display element that is irradiated with light from the light source device and forms image light;
a projection optical system that projects the image light emitted from the display element onto a screen;
a control unit that controls the display element and the light source device;
A projection device comprising:

10 Projection device 12 Front panel 13 Rear panel 14 Right panel 15 Left panel 21 Input/output connector section 22 Input/output interface 23 Image conversion section 24 Display encoder 25 Video RAM
26 Display drive unit 31 Image compression/expansion unit 32 Memory card 35 Ir receiving unit 36 Ir processing unit 37 Key/indicator unit 38 Control unit 41 Light source control circuit 43 Cooling fan drive control circuit 45 Lens motor 47 Audio processing unit 48 Speaker 51 Display element 60 Light source device 70 Excitation light irradiation device 71 Blue laser diode 73 Collimator lens 75 Reflection mirror group 80 Green light source device 90 Cooling device 91 Heat transfer member 92 Fin 93 Air blower device 94 Heat pipe 94A First heat pipe 94B Second heat pipe 100 Fluorescent wheel device 101 Phosphor wheel 110 Motor 111 Condenser lens group 115 Condenser lens 120 Red light source device 121 Red light source 125 Condenser lens group 140 Light guiding optical system 141 First dichroic mirror 143 Reflecting mirror 145 Reflecting mirror 146 Collecting lens 147 Collecting lens 148 Second dichroic mirror 149 Collecting lens 170 Light source side optical system 173 Collecting lens 175 Light guiding device 178 Collecting lens 181 Optical axis conversion mirror 183 Collecting lens 185 Illumination mirror 195 Condenser lens 220 Projection optical system 225 Fixed lens group 235 Movable lens group 241 Control circuit board 911 Groove 920 Heat sink 921 Main body 922a Upper plate 922a1 Tip 922a2 Base end 922b Lower plate 923 Through hole 924 Straightening member 924a Guide surface 931 Case 931a Air intake 931b Air intake 932 Fan L, L1, L2, L11, L21 Air P Flow path P1 Flow path axis SB System bus

Claims (7)

a heat dissipation member that forms a flow path;
a first heat generating member and a second heat generating member connected to the heat dissipation member within the flow path;
a first flow straightening member provided in the flow path and configured to guide the cooling fluid flowing in the flow path to the first heat generating member; and a second flow straightening member configured to guide the cooling fluid to the second heat generating member.
a third heat generating member provided upstream of the flow path relative to the first heat generating member;
Equipped with
a length of the first flow straightening member provided on the upstream side of the flow path is shorter than a length of the second flow straightening member provided on the downstream side of the flow path;
A cooling device characterized by: the first heat generating member provided on the upstream side of the flow path and the second heat generating member provided on the downstream side of the flow path are arranged side by side in a flow path axial direction of the flow path,
the first and second flow straightening members are provided below the first and second heat generating members, and have guide surfaces that guide the cooling fluid flowing from upstream in the flow path upward.
2. The cooling device according to claim 1. The cooling device described in claim 1 or claim 2, characterized in that the first flow straightening member and the second flow straightening member are arranged to slope upward as they move from the upstream side to the downstream side of the flow path. the heat dissipation member is a fin formed of a metal plate on which the first and second flow rectifying members are provided,
The first and second flow rectifying members are formed by bending a portion of the fin.
4. The cooling device according to claim 1, wherein the cooling device is a cooling device having a cooling function. a heat sink including a cylindrical flow path that is open in a flow path axial direction of the flow path and includes a plurality of fins to which the first heat generating member and the second heat generating member are connected,
the first heat generating member and the second heat generating member are heat pipes connected to a heat source side;
5. The cooling device according to claim 4. A cooling device according to any one of claims 1 to 5;
a light source element that is a heat source thermally connected to the heat dissipation member;
A light source device comprising: The light source device according to claim 6 ;
a display element that is irradiated with light from the light source device and forms image light;
a projection optical system that projects the image light emitted from the display element onto a screen;
a control unit that controls the display element and the light source device;
A projection device comprising: