JP5237012B2 - Heating part cooling device and liquid crystal projector device - Google Patents

Description

  The present invention relates to a heat generating member of an electronic apparatus and an electronic projection device, and more particularly to a heat generating portion cooling device and a liquid crystal projector device that cool a plurality of parallel flat plates by blowing air from a plurality of directions.

  In recent years, electronic devices are required to have high functions and to be downsized at the same time. Therefore, many electronic devices with high heat generation density have been developed by high-density mounting, and improvement of cooling technology is required.

  In particular, the liquid crystal projector apparatus has been increased in brightness in order to realize a brighter and clearer image, and an improvement in the cooling method has been demanded in order to maintain the life of optical components that generate heat by light irradiation.

  14 to 17 show the structure and cooling method of a conventional liquid crystal projector apparatus. FIG. 14 is an overview of a general liquid crystal projector apparatus.

  FIG. 15 is a diagram showing the internal structure of the liquid crystal projector apparatus. FIG. 16 is a schematic configuration diagram of the inside of the liquid crystal projector device.

  As shown in FIG. 16, a cooling fan 3 and an air cooling duct 4 for forcibly cooling the liquid crystal unit 2 are mounted in the housing of the liquid crystal projector device 1, and in addition to this, a light source 5 and a power supply unit 10. A lamp cooling fan 7 for cooling the air and the like, an exhaust fan 9 for exhausting the housing, and the like are provided as necessary.

  Individually, a general cooling method of the liquid crystal unit 2 of the liquid crystal projector apparatus 1 will be described with reference to FIG. FIG. 17 is a configuration diagram of a liquid crystal unit cooling unit of the liquid crystal projector apparatus.

  In FIG. 17, the liquid crystal unit 2 composed of the incident side polarizing plate 12, the liquid crystal panel 13, and the output side polarizing plate 14 is provided for each color light of R / G / B, and below that is a cooling fan. 3 and the air cooling duct 15 are arranged.

  During the operation of the air cooling device 15, as shown in FIG. 17, each liquid crystal unit unit 2 is moved from the lower end of the liquid crystal unit unit 2 through the discharge port 17 provided to the air cooling duct 4 with the air blow 16 from the cooling fan 3. Forced air cooling is performed by ventilating the space between the incident side polarizing plate 12, the liquid crystal panel 13, and the outgoing side polarizing plate 14.

  In recent years, liquid crystal projector apparatuses have been increasingly demanded for miniaturization and high brightness in accordance with the diversification of usage methods. In order to meet such a demand, an increase in lamp output and a reduction in the size of the display device have been promoted. As a result, the luminous flux density of light incident on the liquid crystal unit portion is increased, and each unit constituting the liquid crystal unit portion 2 is increased. The heat load is steadily increasing, and it is difficult to cool the conventional air cooling system.

  As a method for increasing the heat transfer coefficient by forced air cooling, a collision jet can be cited. Collision jet cooling has the effect of destroying the temperature boundary layer and locally increasing the heat transfer coefficient by colliding the refrigerant (air) perpendicularly to the heat generation surface, making the flow highly turbulent and cooling performance It is a method to improve.

  However, when cooling a heating element (liquid crystal panel or polarizing plate) arranged in parallel in a narrow state between plates (hereinafter referred to as “between narrow plates”) like a liquid crystal unit of a projector device, the conventional air-cooling method has a problem that Since air flows in parallel and a laminar flow is formed, the improvement in cooling performance with respect to an increase in wind speed has not been sufficient.

Therefore, for example, Patent Document 1 discloses that air is blown from two different directions between the plates formed by the liquid crystal panel, the polarizing plate, etc. in the vicinity of the liquid crystal unit as shown in FIG. A technique for improving the local heat transfer coefficient by forming an air flow perpendicular to the heat generating surface without impeding the transmission of light is disclosed.
JP 2008-107387 A

  However, although the method disclosed in Patent Document 1 provides higher cooling performance than the conventional air cooling method, it is configured to blow air between the narrow plates from different directions and impinge on the heat generation surface. Therefore, the cooling performance depends on the combination of the size of the heat generating surface and the size of the jet (that is, the duct width).

  Therefore, adopting an impinging jet cooling configuration that can always provide better cooling performance than the conventional air cooling method at any heating surface size increases the versatility of the design, development cost and lead time. This will contribute to the provision of excellent cooling solutions for electronic devices with high heat loads.

  Therefore, the present invention has been made in view of the above problems, and an object thereof is to provide a collision jet cooling structure that always exhibits excellent cooling performance without depending on the size of the heat generating surface.

  In order to solve the above-described problem, the heat generating portion cooling device according to the present invention includes one or more flat plate-like heat generating component groups arranged in parallel so that the in-plane directions are the same, and having a heat generating portion inside the surface, and a flat plate shape. Two or more air cooling means for blowing air from different directions to the heat generating component group to generate one or more air collision portions in one or more gaps of the flat plate heat generating component group, and the air cooling means jet air The maximum width of the flat plate-like heating component in which the width of at least one of the jetting ports is perpendicular to the direction of the air flow discharged from the jet port of the flat plate-like heating component toward the flat plate-like heating component group And air jetting means that is 0.8 times or less.

  When the maximum width of the flat plate-like heat generating components on the both sides of the different gaps formed by the flat plate-like heat generating component group is different, the air jetting means is set to 0. 0 with respect to the maximum width of the smaller flat plate-like heat generating component. It is characterized by being 8 times or less.

  At least one of the air cooling means has a cooling fan and an air cooling duct.

  The air cooling means has a structure in which at least one air cooling duct branches in the middle, and has two or more air jet outlets.

  The air collision part is characterized by being a collision caused by blowing a secondary flow generated from another air collision part.

  The flat plate-like heat generating component group includes a gap having a collision portion and a gap not having a collision portion.

  The air ejecting means is 0.8 times the maximum width of the flat plate-like heat generating component in which the width of the jet port is orthogonal to the direction of the air flow discharged from the jet port toward the flat plate-shaped heat generating component group. It is the above, It is characterized by blowing and cooling from one direction with respect to the clearance gap which does not have a collision part.

  In addition, a liquid crystal projector device according to the present invention includes any one of the heat generating unit cooling devices described above.

  According to the present invention, the cooling efficiency of the collision jet system can be increased by adopting a configuration in which the width of the ejection port is 0.8 times or less the maximum width of the flat plate-like heat generating component. By using the subsequent secondary flow to cause further collision, it is possible to efficiently cool with a small number of cooling fans even when the heat generation region is dispersed.

  First, in order to find a structure that exhibits the performance of the collision jet, the reason why the cooling performance is improved by the collision jet and the characteristics of the collision jet different from general one-way air cooling will be described below.

  In an impinging jet, it is necessary to clarify the behavior of air flow between narrow plates. Therefore, analysis is performed using a numerical simulation of thermal fluid, which is one of the visualization methods of flow and temperature.

  FIG. 1 shows a distribution of flow velocity vectors in a panel central cross section (AA cross section) parallel to the air blowing direction during panel air cooling by conventional one-way air blowing. As shown in FIG. 18, the flow velocity distribution between the plates immediately after the inflow of the panel is almost constant, but the flow velocity distribution becomes closer to a parabolic distribution as it gradually goes to the rear of the flow immediately after the inflow.

  The amount of heat transferred from the panel to the air is determined by the flow velocity gradient in the vicinity of the panel wall. The larger the flow velocity gradient, the larger the amount of heat transferred and the higher the heat dissipation performance. Accordingly, in the conventional one-way air blowing, the heat dissipation performance gradually deteriorates as the flow goes backward, and the panel temperature at the top of the figure becomes high. Note that this tendency does not depend on the flow velocity during blowing.

  FIG. 2 shows a flow velocity vector when air collides in the vicinity of the center between the panel plates by upper and lower two-way ventilation. The AA cross section is a flow velocity vector near the center of the panel before the collision, and an air flow toward the center is confirmed by a parabolic distribution.

  On the other hand, the BB cross section shows the velocity vector after the collision that flows in the left-right direction after the collision (shown up and down for the sake of display). Unlike the parabolic distribution before the collision, the velocity vector of the secondary flow to the left and right after the collision is almost constant. This is because the turbulent state becomes intense after the collision, and flows left and right while maintaining the turbulent state.

  From this, the secondary flow to the left and right after the collision has a large amount of heat transferred from the panel to the air, and high heat dissipation performance can be obtained. This is the largest reason why the temperature (maximum temperature) of the panel can be lowered by causing collision between two narrow plates by blowing air in two directions.

  Next, in order to clarify the characteristics of the collision cooling, the influence of the duct width of the blowing will be described. FIG. 3 shows the results of a duct width of 10 mm and 20 mm for a panel having a panel width size of 20 mm, for the conventional one-way method and the collision method, respectively.

The left figure shows the panel temperature distribution, and the right figure shows the temperature distribution on the ABC line in the left figure. Here, ABC indicates the initial, middle, and late points in the flow direction. The position of C is different between the one-way method and the collision method, and in the collision method, the left and right central ends are C points.

  First, as described with reference to FIG. 1, the temperature distribution of the one-way system increases toward the rear of the air flow, and the flow velocity distribution becomes a parabolic distribution, so that the panel temperature increases. Further, when the duct width is narrowed, the temperature on both the left and right sides of the panel in which air hardly flows is higher than the center, and the temperatures at the upper right and upper left positions of the panel are increased. Thus, in the case of the one-way method, the duct width should be close to the panel width.

  On the other hand, this tendency is reversed in the collision method. That is, the heat dissipation performance in the collision method is higher when the duct width is narrower than the panel width. In the collision method, after the collision at the center, the secondary flow is generated on the left and right, and the heat dissipation performance of the secondary flow is high, so there is no place where the entire panel is difficult to flow air, and the entire panel can be cooled stably. . At this time, when the duct width is increased to be equal to the panel width, the flow velocity is remarkably lowered, and the cooling performance tends to be lowered.

  As described above, in the collision jet cooling, unlike the conventional cooling method, the cooling performance can be kept high when the duct width is set narrower than the panel width.

  Next, a specific relationship between the size of the panel (heat generating component) and the width of the duct (jet port) for narrowing the duct width in the collision method will be described.

  FIG. 4 shows a cooling fan provided with a specific PQ (static pressure-flow rate) characteristic for a plurality of flat plate-like heating component groups 18 including heating portions 20 arranged in parallel with a space of 1.5 mm between the plates. It is an outline figure at the time of blowing air from a duct.

  Two parallel flat plate-like heat generating component groups 18 including the heat generating portion 20 are surrounded by a heat insulating material 21 and can radiate heat only from a heat radiating surface 22 facing between the plates.

  When a collision jet is used, a cooling fan and a duct are provided as a first air cooling means and a second air cooling means in a pair of upper and lower sides with respect to the flat plate-like heat generating component group 18. In the combination of the first air cooling means and the second air cooling means, the first air cooling means is composed of the first cooling fan 23a and the first air cooling duct 19a, and the second air cooling means is the second cooling fan 23b. And a second air cooling duct 19b.

  The first cooling fan 23a and the second cooling fan 23b have the same PQ characteristics, and the static pressure (P) is the same as that of the cooling fan used in forced air cooling from one direction. (Q) is halved. Therefore, the first cooling fan 23a and the second cooling fan 23b have the same PQ characteristics as those obtained by dividing the cooling fans used for forced air cooling from one direction into two hands.

  FIG. 5 shows a plate formed in a parallel flat plate-like heat generating component group in response to a change in the width d of the jet port provided at a position 15 mm away from the flat plate-like heat generating component group (width 20 mm) in the configuration shown in FIG. The characteristic figure of the flow velocity of the air which flows in between is shown.

  As for the air blowing from one direction, the solid line and the result in the collision jet are shown by the dotted line. In the impinging jet, the inflow speed between the plates decreases remarkably as the value of the width d of the duct outlet on the horizontal axis increases, and further, as the value of the heat generating component length L decreases, The inflow speed will decrease.

In the impinging jet, the collision between the opposing wind and the narrow plate causes the pressure to increase due to the colliding wind, making it difficult for air to flow into the space between the plates. .

  FIG. 6 shows a group of flat plate-like heat generating components that have the same heat generation amount per unit volume using the same cooling fan and air cooling duct shape as the configuration shown in FIG. For each change in the heat generating part length L, a plot of the maximum surface temperature rise of the plate-like heat generating component group with respect to the change in the width d of the jet nozzle set at a position 15 mm away from the component when air-cooled. They are arranged.

  The values of L shown in FIGS. 6A to 6D are (a): 10 mm, (b): 15 mm, (c): 20 mm, and (d): 30 mm, respectively. In all cases, the tendency of the temperature change is similar. As the width d of the jet outlet increases, the temperature rise of the impinging jet increases, and the forced air cooling from one direction reduces the temperature rise.

  FIG. 7 is a graph in which the influence on the maximum temperature of the heat-generating component is plotted by making the dimension of the heat-generating component width dimensionless for each of the jet outlet width and the heat-generating component length.

  Referring to FIG. 7 and seeing the effect of the jet width on the maximum temperature of the heat generating component, if the value of the jet width / heat generating component width is 0.8 and the jet width is smaller than that, Depending on the length of the heat generating component, the maximum temperature will change. That is, when the value of the jet outlet width / heat generating component width is 0.8 or less, the maximum temperature of the heat generating component can be efficiently reduced. The reason for this tendency is that when the value of the jet outlet width / heat generating component width becomes smaller than 0.8, the increase in the flow velocity at the jet outlet becomes remarkable, and as a result, the temperature decreases.

  By utilizing the above-mentioned phenomenon and characteristics of the collision method, it is possible to efficiently cool the flat plate-like heat generating component by providing a plurality of collision locations. In a structure with a plurality of printed circuit boards mounted on a flat plate-like heat generating component, for example, an electronic device, which has a relatively large area and a narrow gap, it is possible to cool the entire printed circuit board uniformly by having multiple collision locations. It becomes.

  Also, the printed circuit board may have components with a large amount of heat scattered at a plurality of locations depending on the type of components mounted on the printed circuit board, and there is a demand to increase the number of collision locations with as few air blows as possible. In this case, by utilizing the secondary flow generated after the collision for the next collision, even a small number of cooling fans or ducts can be efficiently cooled.

(First embodiment)
The configuration and operation of the heating unit cooling device for an electronic device according to the first embodiment of the present invention will be described in detail with reference to the drawings. In this embodiment, in order to facilitate understanding, the electronic apparatus is a liquid crystal image display of a liquid crystal projector apparatus, a flat plate-like heat-generating component, an incident side polarizing plate, a liquid crystal panel, and two sheets constituting a liquid crystal unit section The output side polarizing plate will be described. However, the present invention is not limited to this mode. Cooling of an electronic apparatus that includes a plurality of flat plate-like heat generating components, each of which has a surface facing each other at an interval, and at least one of the surfaces facing each other is a heat generating portion. It can also be applied as a device.

  FIG. 8 is a schematic exploded perspective view of the heat generating part cooling device of the liquid crystal image display according to the first embodiment of the present invention.

The cooling device 24 is prepared for each color light of R / G / B at the upper and lower ends of the liquid crystal unit portion that constitutes each of the incident side polarizing plate 25, the liquid crystal panel 26, and the outgoing side polarizing plates 27 and 28 as a unit. A second air cooling unit, which is arranged so as to face each other and includes a first cooling fan 29 and a first air cooling duct 30, and a second cooling fan 32 and a second air cooling duct 33 which are also the same. Part 34.

  Next, the cooling effect | action by the cooling device 24 in this embodiment is demonstrated using FIG. FIG. 9 is a cross-sectional view of a liquid crystal unit portion of one color light portion out of three R / G / B liquid crystal panels included in the liquid crystal projector.

  The first air blow 35 is from the lower side of the liquid crystal unit section to the space between the incident side polarizing plate 25 and the liquid crystal panel 26, the space between the liquid crystal panel 26 and the outgoing side polarizing plate A27, and the outgoing side polarizing plate A27 and the outgoing side polarizing plate. It is sent out upward from the space with B28.

  Similarly, the second air blow 36 is a space between the incident side polarizing plate 25 and the liquid crystal panel 26, and a space between the liquid crystal panel 26 and the outgoing side polarizing plate A27, and between the outgoing side polarizing plate A27 and the outgoing side polarizing plate B28. It is sent downward from the space.

  The first blower 35 and the second blower 36 are equivalent in the amount of air blown by the first cooling fan and the second cooling fan, and the ventilation resistance of the first air cooling duct 30 and the second air cooling duct 33 is the same. Are equal, they collide with each other in the state of being opposed at the center of the space between the units (collision plane aa ′).

  Further, the width in the in-plane direction of the polarizing plate of the jet outlet 37 of the duct that sends out the first air blow and the jet outlet 38 of the duct that sends out the second air blow is 10 mm. The size of the liquid crystal panel 26 is 0.7 inches, and a heat dissipation glass substrate in which a polarizing film of almost the same size is formed on the incident side polarizing plate 25, the outgoing side polarizing plate A27, and the outgoing side polarizing plate B28. Is attached.

  FIG. 10 shows an enlarged view of the wind collision portion shown in FIG. FIG. 10A is an enlarged view of the space between the output side polarizing plate A27 and the output side polarizing plate B28.

  The first blower 25 and the second blower 36 collide at the center of the space between the units (collision plane aa ′) and go to the light transmission surfaces of the emission side polarization plate A27 and the emission side polarization plate B28. A swirling flow is generated, and a vertical jet is generated and cooled without impeding the passage of light. At this time, the width of the duct outlet is 10 mm, and the width of the output side polarizing plate A and the output side polarizing plate B is 20 mm. Therefore, the duct outlet width is 0.5 times the width of the output side polarizing plates A and B. It becomes. It was confirmed that the maximum temperatures of the output side polarizing plates A and B in this state were kept low.

  On the other hand, FIG. 10B is an enlarged view of the space between the incident side polarizing plate 25 and the liquid crystal panel 26. The first air blow 35 and the second air blow 36 collide at the center of the space between the units (impact surface aa ′), and the swirl flows toward the light transmitting surfaces of the incident-side polarizing plate 25 and the liquid crystal panel 26. Is generated, and a vertical jet is generated and cooled without interfering with the passage of light.

  At this time, the duct outlet width is 10 mm, and the width of the liquid crystal panel 26 having a small size in the depth direction in the drawing compared to the incident side polarizing plate 25 is 14 mm. Therefore, the duct outlet width is about the width of the liquid crystal panel. It becomes 0.7 times. It was confirmed that the maximum temperatures of the output side polarizing plates A and B in this state were kept low. The heat radiating surface 22 of the liquid crystal panel 26 is in a recess, and it is difficult for the wind to reach by forced air cooling from one direction, but a swirling flow is generated in the impinging jet.

  From the above, it was confirmed that the temperature of the heat generating component can be kept low when the width of the jet port is smaller than 0.8 times the maximum width of the flat plate-shaped heat generating component.

In a projector device or the like, a great effect can be obtained when the distance between the plates formed by the plurality of flat plate-like heat-generating components is narrow (up to about 5 mm).

(Second Embodiment)
Next, a cooling device according to a second embodiment of the present invention will be described in detail with reference to the drawings.

  FIG. 11 is a schematic diagram of the second embodiment of the present invention. The air sent from the cooling fan 39 is 2 by the first air cooling duct 40 and the second air cooling duct 41 branched from the middle thereof. The air is blown to the liquid crystal unit 2 in the direction.

  According to the present embodiment, the first air blowing 42 that causes the first air cooling duct 39 to vent upward from the lower side of the liquid crystal unit unit 2 and the second air blowing 43 that is ventilated from the side of the liquid crystal unit unit 2 are provided. In each space between the liquid crystal unit parts 2, collision as blast having two different vectors (orthogonal vectors) occurs, so that a high cooling effect can be obtained.

  If the air cooling duct is branched from the middle as in this configuration, the number of fans mounted can be reduced to reduce cost and noise, and the air cooling duct can be made small, so that it can be easily applied to a small projector device. .

  In the above cooling structure, the duct outlet width is 10 mm for both the first air cooling duct 40 and the second air cooling duct 41, and the width of the liquid crystal panel, which is the smallest panel of the liquid crystal unit 2, is 14 mm. is there. The duct outlet width at this time is about 0.7 times the width of the liquid crystal panel. In this state, it was confirmed that the maximum temperature of the liquid crystal panel was kept low.

(Third embodiment)
A cooling device according to a third embodiment of the present invention will be described in detail with reference to the drawings. FIG. 12 is a schematic view of a cooling device according to the third embodiment of the present invention.

  A first air-cooling duct 44 and a second air-cooling duct 45 branched from a common duct are respectively arranged on the lower side with respect to the liquid crystal unit portion 2, and a third one branched from the common duct is arranged on the upper side. An air cooling duct 46 and a fourth air cooling duct 47 are arranged.

  The air blowing from the first air cooling duct 44 and the air blowing from the third air cooling duct 46 cause the first collision 48 in the space of the gap of the liquid crystal unit 2 and the first secondary flow 49 to the right side. generate.

  On the other hand, the air blown from the second air cooling duct 45 and the air blown from the fourth air cooling duct 47 cause a second collision 50 in the gap space of the liquid crystal unit 2 and the second secondary flow to the left side. 51 is generated.

  Due to the first secondary flow 49 and the second secondary flow 51 facing each other, a third collision 52, which is a collision between the secondary flows, is generated in a space near the center of the liquid crystal unit 2. To do.

  The collision part and the resulting secondary flow have the effect of increasing the heat transferred from the liquid crystal unit part 2 to the air, but in this embodiment, the collision part was one place in the first and second embodiments. Therefore, the heat radiation efficiency of the liquid crystal unit 2 is increased, and the heat radiation efficiency in each panel can be made uniform.

  The maximum width of the liquid crystal panel, which is the minimum size in the liquid crystal unit 2, is 14 mm, and the widths of the outlets of the first to fourth air-cooling ducts are 2 mm. At this time, the width of the ejection port is 0.14 times the maximum width of the liquid crystal panel, and is smaller than 0.8 times. Thus, it was confirmed that by making the width of the jet outlet smaller than 0.8 times, the flow velocity of the collision jet can be increased and the cooling efficiency of the liquid crystal unit 2 can be improved.

(Fourth embodiment)
A cooling device according to a fourth embodiment of the present invention will be described in detail with reference to the drawings. FIG. 13 is a schematic diagram of a cooling device according to the fourth embodiment of the present invention.

  13A is a side view, FIG. 13B is a top view, and FIG. 13C is a bottom view. As shown in FIG. 13 (a), the present cooling device is composed of four flat plates including an incident side polarizing plate 25, a liquid crystal panel 26, an outgoing side polarizing plate A27, and an outgoing side polarizing plate B28 from the incident light side (right side in the figure). Are provided in parallel.

  A first air cooling duct 53 is installed on the lower side of the four flat plates, and a second air cooling duct 54 is installed on the upper side.

  Among the four flat plates, the liquid crystal panel 26 generates a larger amount of heat than the other three flat plates. Therefore, two gap spaces related to the cooling of the liquid crystal panel (one is a gap space between the incident side polarizing plate 25 and the liquid crystal panel 26, and the other is a gap space between the liquid crystal panel 26 and the emission side polarizing plate A27) are impinging jets. For the gap space between the output side polarizing plate A27 and the output side polarizing plate B28, which is not related to the cooling of the liquid crystal panel, air cooling by the one-way method is used.

  FIG.13 (b) is the figure which looked at the lower side from the center AA cross section of Fig.13 (a). In FIG. 13 (b), the hatched portion indicates the outlet of the first air cooling duct 53. The jet outlet of the first air-cooling duct 53 is a duct for a collision jet, and includes two gap spaces related to cooling of the liquid crystal panel (one is a gap space between the incident-side polarizing plate 25 and the liquid crystal panel 26, and the other is one. Is formed so that air flows through the space between the liquid crystal panel 26 and the output side polarizing plate A27.

  The maximum width of the liquid crystal panel is 14 mm, and the width of the jet outlet of the first air cooling duct 53 is 6 mm. At this time, the width of the jet outlet of the first air cooling duct 53 is 0.43 times the maximum width of the liquid crystal panel, and is smaller than 0.8 times, so that the cooling efficiency of the collision jet is high.

  FIG.13 (c) is the figure which looked at the upper side from the center AA cross section of Fig.13 (a). In FIG. 13 (c), the hatched portion indicates the jet outlet of the second air cooling duct 54. The jet outlet of the second air cooling duct 54 is composed of two areas, a collision jet cooling area (right side in the figure) and a unidirectional cooling area (left side in the figure).

  The area for cooling the impinging jet (the right side in the figure) has two gap spaces related to the cooling of the liquid crystal panel (one is the gap space between the incident-side polarizing plate 25 and the liquid crystal panel 26, and the other is the liquid crystal panel 26 and the exit. It is in a position where air can be blown into the gap between the side polarizing plates A27, and the width of the jet outlet (vertical length in the figure) is 6 mm, which is 0.43 times the maximum width of the liquid crystal panel, from 0.8 times Is also small.

  On the other hand, the region for unidirectional cooling (the left side in the figure) of the second air cooling duct 54 is at a position where air can be blown to the output side polarizing plate A27 and the output side polarizing plate B28, and the width of the ejection port is 20 mm. It is 1 time of 20 mm which is the width | variety of the side polarizing plate A27 and the output side polarizing plate B28. For this reason, the cooling performance is high as unidirectional air cooling.

In this way, there are four plate-like heat generating components, and by changing the width of the duct outlet according to the amount of each heat generation according to each gap space, it is possible to realize the optimum and maximum cooling performance as a whole. is there.

  As described above, in the first to fourth embodiments, the cooling device for the liquid crystal unit of the liquid crystal projector device has been described as an example. However, the application target of the present invention is not limited to this, and in other electronic devices It is obvious that the same effect can be obtained even if the present invention is applied to the air cooling method for the flat plate-like heating component group.

  For example, a large server installed in a data center employs a configuration in which a plurality of boards equipped with a CPU, memory, hard disk, power supply, etc. are arranged at a pitch of several centimeters in order to increase mounting density (generally, blades In this case as well, the gap between the boards or components is small, and the conventional one-way air cooling has a limited cooling performance. For this reason, as in the present invention, impinging jet cooling having two or more air-cooling means in which the blower outlet width is smaller than 0.8 times the maximum width of the board is very effective.

It is a figure which shows the flow velocity vector distribution between the panel plates of the conventional one-way air cooling shown as a comparison in order to show the effectiveness of the effect | action of this invention. It is a figure which shows the flow velocity vector distribution between the panel boards in the collision air cooling for showing the effectiveness of the effect | action of this invention. It is a panel temperature distribution figure in the collision air cooling for showing the effectiveness of the effect | action of this invention. It is a panel periphery basic | foundation structural drawing which shows the various influence in the collision air cooling for showing the effectiveness of the effect | action of this invention. It is a figure which shows the relationship between the jet nozzle width | variety and the flow velocity in the collision air cooling for showing the effectiveness of the effect | action of this invention. It is a figure which shows the relationship between the jet nozzle width | variety and temperature in collision air cooling for showing the effectiveness of the effect | action of this invention. It is a figure which shows the nozzle outlet width dependence of the panel maximum temperature in the collision air cooling for showing the effectiveness of the effect | action of this invention, and heat-emitting component length. 1 is a schematic exploded perspective view of a heat generating unit cooling device of a liquid crystal projector device according to a first embodiment of the present invention. FIG. 2 is a schematic cross-sectional view of a liquid crystal unit portion of a liquid crystal projector using collision jet cooling in the basic mode of the first embodiment of the present invention. It is the figure which expanded the space (a) of the output side polarizing plate and output side polarizing plate of the 1st Embodiment of this invention, and the space (b) of an incident side polarizing plate and a liquid crystal panel. It is a typical sectional view of a liquid crystal unit part of a liquid crystal projector using collision jet cooling in a basic mode of a 2nd embodiment of the present invention. It is typical sectional drawing of the liquid-crystal unit part of the liquid-crystal projector using the collision jet cooling in the basic mode of the 3rd Embodiment of this invention. It is a typical sectional view of a liquid crystal unit part of a liquid crystal projector using collision jet cooling in a basic mode of a 4th embodiment of the present invention. It is an external view of a general liquid crystal projector product. It is an internal structure figure of a general liquid crystal projector device. It is a typical block diagram inside a general liquid crystal projector device. It is a block diagram of the cooling part of the liquid crystal unit part of the conventional liquid crystal projector apparatus. It is a schematic diagram of the structure of the cooling part which shows the prior art example of liquid crystal unit cooling.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Liquid crystal projector apparatus 2 Liquid crystal unit part 3 Cooling fan 3a 1st cooling fan 3b 2nd cooling fan 4 Air cooling duct 5 Light source 6 Reflector 7 Lamp cooling fan 8 Lamp cooling duct 9 Exhaust fan 10 Power supply unit 11 Projection lens 12 Incident side polarizing plate 13 Liquid crystal panel 14 Outgoing side polarizing plate 15 Air cooling device 16 Blower 17 Discharge port 18 Flat plate-like heat generating component group 19a First air cooling duct 19b Second air cooling duct 20 Heat generating part 21 Heat insulating material 22 Heat radiation surface 23a First Cooling fan 23b second cooling fan 24 cooling device 25 incident side polarizing plate 26 liquid crystal panel 27 outgoing side polarizing plate A
28 Output-side polarizing plate B
29 1st cooling fan 30 1st air cooling duct 31 1st air cooling part 32 2nd cooling fan 33 2nd air cooling duct 34 2nd air cooling part 35 1st ventilation 36 2nd ventilation 37 1st Duct outlet 38 Second duct outlet 39 Cooling fan 40 First air cooling duct 41 Second air cooling duct 42 First air blowing 43 Second air blowing 44 First air cooling duct 45 Second air cooling duct 46 Third Air cooling duct 47 fourth air cooling duct 48 first collision 49 first secondary flow 50 second collision 51 second secondary flow 52 third collision 53 first air cooling duct 54 second air cooling duct

Claims (7)

One or more plate-like heat generating component groups arranged in parallel so that the in-plane directions are the same and having a heat generating part inside the surface;
Two or more air cooling means for blowing air from different directions with respect to the flat plate-like heat generating component group, and generating one or more air collision portions in one or more gaps of the flat plate-like heat generating component group;
The air-cooling means has a width of at least one or more outlets for ejecting air with respect to the direction of the flow of air discharged from the outlet of the flat plate-like heating component toward the flat plate-like heating component group. and air jetting means is 0.8 times or less with respect to the maximum width of the flat heat generating component orthogonal orientation, and possess,
The heating unit cooling device according to claim 1, wherein the air collision part is a collision caused by blowing a secondary flow generated from another air collision part .   When the maximum width of the flat plate-like heat generating components on both sides of the different gaps formed by the flat plate-shaped heat generating component group is different, the air jetting unit is different from the maximum width of the smaller flat plate-shaped heat generating component. The heat generating part cooling device according to claim 1, wherein the heat generating part cooling device is 0.8 times or less.   The heating part cooling device according to claim 1 or 2, wherein at least one of the air cooling means includes a cooling fan and an air cooling duct.   The heating unit cooling device according to any one of claims 1 to 3, wherein the air cooling means has a structure in which at least one air cooling duct branches in the middle, and has two or more air jets. . The heating unit cooling device according to any one of claims 1 to 4, wherein the flat plate-like heat generating component group includes a gap having a collision portion and a gap not having a collision portion. The air ejection means has a width of the ejection port of 0. 0 with respect to the maximum width of the flat plate-like heating component in a direction perpendicular to the direction of air flow discharged from the jet port toward the plate-like heating component group. More than 8 times,
The heat generating part cooling device according to claim 5, wherein the gap that does not have the collision part is cooled by blowing air from one direction. A liquid crystal projector apparatus comprising the heat generating part cooling device according to claim 1.

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