HEAT DISSIPATION MODULE AND PROJECTION DEVICE

A heat dissipation module, configured for heat dissipation of at least one first heat source and at least one second heat source, and including a first heat sink, a second heat sink, a first pipe, and a second pipe, is provided. The first heat sink and the first heat source are connected to each other through the first pipe to form a first loop, so that a liquid medium flows through the first heat sink for heat exchange and then flows to the first heat source for circulating heat dissipation. The second heat sink and the second heat source are connected to each other through the second pipe to form a second loop, so that the liquid medium flows through the second heat sink for heat exchange and then flows to the second heat source for circulating heat dissipation. A projection device, including the heat dissipation module, is also provided.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the priority benefit of China application serial no. 202022824630.4, filed on Nov. 30, 2020. The entirety of the above-mentioned patent application is hereby incorporated by reference herein and made a part of this specification.

BACKGROUND

Technical Field

The invention relates to a heat dissipation module and a projection device, and particularly relates to a heat dissipation module with a better heat dissipation effect and a projection device using the heat dissipation module.

Description of Related Art

In a solid-state light source projection system, an air cooling method is generally used to dissipate heat of a light source. Regarding a current design of air cooling heat dissipation, a thermal resistance thereof is about 0.12° C./W. If heat increases, when the thermal resistance drops below 0.1° C./W, thermoelectric cooling (TEC) or a liquid cooling technology must be used for heat dissipation. The liquid cooling has an advantage of low thermal resistance and has better heat exchange efficiency than air cooling. When there are space constraints and low thermal resistance requirements, the liquid cooling is generally selected for the design of heat dissipation.

Generally, in a heat dissipation module of a single liquid cooling loop, when a temperature of a heat source rises or a number of heat sources continues to increase, if an area of a heat sink remains the same, a liquid temperature at an outlet of the heat sink will be too high. At this time, even though a component with the lowest operating temperature is placed on a first group of liquid-cooling plates for cooling, there will still be situations where the liquid temperature is higher than the operating temperature of the component. In order to make the components with lower operating temperatures to also meet heat dissipation requirements, in addition to increasing a number of fans and improving performance of driving motors, a volume of the heat sink may also be increased. However, the above approaches may cause the liquid cooling system to become larger and result in a poor overall space utilization rate. Furthermore, in order to improve the space utilization rate, the heat sink is split and respectively placed upstream and downstream of the system, but after the air passes through the upstream heat sink of the system, an air temperature in the system has risen, and when the air with the higher temperature is used to cool the downstream heat sink of the system, and the cooling effect is not good. In addition, as a total heat of the system increases and all components are on a same liquid circulation, the liquid temperature at the outlet of the heat sink is still increased, and it is impossible to provide cooling liquid with a lower temperature for the components with lower operating temperatures.

SUMMARY

The invention is directed to a heat dissipation module, which has better heat dissipation efficiency.

The invention is directed to a projection device including the aforementioned heat dissipation module, in which under a condition that a number of fans is not increased, a cooling area is increased and a rotation speed of the fans is reduced, thereby reducing system noise.

Other objects and advantages of the invention may be further illustrated by the technical features broadly embodied and described as follows.

In order to achieve one or a portion of or all of the objects or other objects, an embodiment of the invention provides a heat dissipation module for heat dissipation of at least one first heat source and at least one second heat source of a projection device. The heat dissipation module includes a first heat sink, a second heat sink, a first pipe, and a second pipe. The first heat sink and the first heat source are connected to each other through the first pipe to form a first loop, so that a liquid medium flows through the first heat sink for heat exchange and then flows to the first heat source for circulating heat dissipation. The second heat sink and the second heat source are connected to each other through the second pipe to form a second loop, so that the liquid medium flows through the second heat sink for heat exchange and then flows to the second heat source for circulating heat dissipation.

In order to achieve one or a portion of or all of the objects or other objects, an embodiment of the invention provides a projection device including a casing, a projection lens, at least one first heat source, at least one second heat source, and the heat dissipation module of any of the above embodiments. The projection lens is disposed through the casing. The first heat source, the second heat source and the heat dissipation module are arranged in the casing.

Based on the above description, the embodiments of the invention have at least one of the following advantages or effects. In the design of the heat dissipation module of the invention, the first heat sink and the first heat source form the first loop through the first pipe, the second heat sink and the second heat source form the second circuit through the second pipe, and the liquid medium in the pipes flows through the heat sinks for heat exchange and then flows to the heat sources for circulating heat dissipation. In other words, by using two sets of independent liquid cooling loops to respectively dissipate heat of the first heat source and the second heat source with different operating temperatures, the heat dissipation module of the invention may have better heat dissipation efficiency. In addition, the projection device using the heat dissipation module of the invention may have increased heat dissipation area without increasing a number of fans, and may reduce a rotation speed of the fans, thereby reducing system noise.

DESCRIPTION OF THE EMBODIMENTS

FIG. 1Ais a schematic diagram of a projection device according to an embodiment of the invention.FIG. 1Bis a side view schematic diagram of a first heat sink and a second heat sink of a heat dissipation module inFIG. 1A. Referring toFIG. 1Afirst, in the embodiment, the projection device10aincludes a casing20, a projection lens30, at least one first heat source (two first heat sources40a,40bare schematically illustrated), at least one second heat source (four second heat sources50a,50b,50c,50dare schematically illustrated), and a heat dissipation module100a.The projection lens30is disposed through the casing20, and the first heat sources40a,40b,the second heat sources50a,50b,50c,50dand the heat dissipation module100aare disposed in the casing20.

Further, the heat dissipation module100aof the embodiment includes a first heat sink110, a second heat sink120a,a first pipe130, and a second pipe140. The first heat sink110and the first heat sources40a,40bare connected to each other through the first pipe130to form a first loop, so that a liquid medium F flows through the first heat sink110for heat exchange and then flows to the first heat sources40aand40bfor circulating heat dissipation. Namely, the liquid medium F is filled in the first pipe130and flows in the first pipe130, where the liquid medium F absorbs the heat of the first heat sources40aand40b,and then flows into the first heat sink110, and the liquid medium F flowing into the first heat sink110conducts heat exchange with the first heat sink110, and then flows to the first heat sources40aand40bfor circulating heat dissipation.

The second heat sink120aand the second heat sources50a,50b,50c,50dare connected to each other through the second pipe140to form a second loop, so that the liquid medium F flows through the second heat sink120afor heat exchange and then flows to the second heat sources50a,50b,50cand50dfor circulating heat dissipation. Namely, the liquid medium F is filled in the second pipe140and flows in the second pipe140, where the liquid medium F absorbs the heat of the second heat sources50a,50b,50cand50d,and then flows into the second heat sink120a,and the liquid medium F flowing into the second heat sink120aconducts heat exchange with the second heat sink120a,and then flows to the second heat sources50a,50b,50cand50dfor circulating heat dissipation.

The liquid medium F in the first pipe130and the second pipe140may be the same, and the liquid medium F is, for example, liquid. In another embodiment that is not illustrated, the liquid medium F in the first pipe130and the second pipe140may also be different, which is still within a scope of the invention.

Particularly, an operating temperature of the first heat sources40aand40bof the embodiment is different from an operating temperature of the second heat sources50a,50b,50cand50d.In the embodiment, the operating temperature of the first heat sources40a,40bis lower than the operating temperature of the second heat sources50a,50b,50cand50d.To be specific, the first heat sources40aand40bare, for example, red light sources of the projection device10a.For the requirement of brightness, a temperature resistance is below 45° C., so that the first heat sources40aand40bare designed to have a first operating temperature, and the first operating temperature is 35° C. The second heat sources50a,50b,50cand50dare, for example, blue light sources of the projection device10a.For the requirement of brightness, the temperature resistance is below 65° C., so that the second heat sources50a,50b,50cand50dare designed to have a second operating temperature, and the second operating temperature is 55° C.

In another embodiment, under the condition that the operating temperature of the first heat sources40aand40bis less than the operating temperature of the second heat sources50a,50b,50cand50d,the first heat sources40aand40bare, for example, but not limited to, a red light source and a light valve module of the projection device10a,and the second heat sources50a,50b,50cand50dare, for example, but not limited to, two sets of blue light sources, a motor module and a circuit module of the projection device10a.

In other words, the invention provides two liquid cooling heat dissipation loops, where a total heat amount of the first heat sources is lower than a total heat amount of the second heat sources, i.e., the first loop dissipates heat of the first heat sources with a lower operating temperature, and the second loop dissipates heat of the second heat sources with a higher operating temperature. Under such design, after the heat dissipation module and the projection device are operated (for example, for 10 minutes), the first heat sources have the first operating temperature and the second heat sources have the second operating temperature, and the first operating temperature is low than the second operating temperature.

In addition, a temperature increase rate of the liquid medium F in the first pipe130is lower than a temperature increase rate of the liquid medium F in the second pipe140. The liquid medium F in the first pipe130has a first temperature, and the liquid medium F in the second pipe140has a second temperature, and the first temperature is less than the second temperature.

Moreover, the casing20of the embodiment has an air inlet22. Since a liquid temperature required by the first loop is relatively low, the first heat sink110may be arranged corresponding to the air inlet22for cooling at a relatively low air temperature. The first heat sink110and the second heat sink120aare arranged in parallel, and relative to a position of the first heat sink110, the second heat sink120ais located at a relatively downstream position in the system of the overall projection device10a.Since the temperature of the air is increased after passing through the first heat sink110, the heat dissipation efficiency of the second heat sink120ais poor, and a liquid temperature at an outlet is also higher. However, the second heat sources50a,50b,50cand50dconnected in series with the second heat sink120ahave a higher operating temperature, so the second loop still meets a heat dissipation requirement and has a better heat dissipation effect.

Referring toFIG. 1Aagain, the casing20further has an air outlet24, where an airflow direction D1of the air inlet22is perpendicular to a projection direction D of the projection lens30, and an airflow direction D2of the air outlet24is parallel to the projection direction D of the projection lens30, but the invention is not limited thereto.

It should be noted that in the embodiment, sizes or structures of the first heat sink110and the second heat sink120amay be freely adjusted according to the required liquid temperature and the amount of dissipated heat, so that the heat dissipation effect of the first heat sink110may be higher than that of the second heat sink120a.

As shown inFIG. 1AandFIG. 1B, in the embodiment, in a flowing direction of the heat dissipation airflow, i.e., in a direction perpendicular to an arrangement direction of a plurality of heat dissipation fins of the first/second heat sinks110and120a,an area of the first heat sink110is larger than an area of the second heat sink120a,and a first height H1of the first heat sink110is smaller than a second height H2of the second heat sink120a,and in a direction parallel to the arrangement direction of the heat dissipation fins of the first/second heat sinks110and120a,a first length L1of the first heat sink of110is greater than a second length L2of the second heat sink120a,where the arrangement direction of the heat dissipation fins of the first/second heat sink110and120aand the length direction are an X direction, the height direction is a Y direction, the flowing direction of the heat dissipation airflow is a Z direction, and the X, Y, and Z directions are perpendicular to each other.

A first area of the first heat sink110is smaller than a second area of the second heat sink120a,i.e., a heat dissipation area of the first heat sink110is smaller than a heat dissipation area of the second heat sink120a.

In other words, the embodiment is not limited to the heat dissipation effects of the first heat sink and the second heat sink, and a designer may determine the heat dissipation area of the heat sink according to a thermal resistance of the heat source to be cooled, where the heat source with a small thermal resistance may be used in combination with the heat sink with a smaller heat dissipation area, and the heat source with a larger thermal resistance may be used in combination with the heat sink with a larger heat dissipation area. The thermal resistance is related to a total heat amount of the heat source corresponding to the heat sink, a temperature of the heat dissipating airflow before entering each heat sink, and an average temperature of the liquid inlet and outlet of the heat sink, where the average temperature of the liquid inlet and outlet and the required operating temperature of the heat source.

In another embodiment, referring toFIG. 1CandFIG. 1D, the first heat sink110aincludes a plurality of first heat dissipation fins112, and the second heat sink120a′ includes a plurality of second heat dissipation fins122. If the heat dissipation areas of the first heat sink110aand the second heat sink120a′ are the same, i.e., when the height and the length of the first heat sink110aand the height and the length of the second heat sink120a′ are the same, a first gap G1between the first heat dissipation fins112may be greater than a second gap G2between the second heat dissipation fins122. In the embodiment, the thermal resistance is changed by changing the gap.

Namely, in the case of the same area, the heat dissipation area may be determined by controlling the gap between the heat dissipation fins. In brief, the heat dissipation area of the heat sink may be determined according to the operating temperature of the heat source to be cooled, where adjustable parameters of the heat sink are the length, height and the gap between the fins, according to the adjustment of the above parameters, the heat sinks with different heat dissipation areas may be obtained.

In addition, referring toFIG. 1A, the heat dissipation module100aof the embodiment further includes at least one fan (three fans150aare schematically illustrated), where the second heat sink120ais disposed between the first heat sink110and the fans150a.The heat dissipation module100amay further include two driving elements160, where the driving elements160are respectively connected to the first pipe130and the second pipe140, and the liquid medium F is driven by the driving element160to circulate in the first pipe130and the second pipe140.

In another embodiment that is not shown, a number of the driving element160may be only one, which is connected to the first pipe130or the second pipe140, so that the liquid medium F is driven by the driving element160to circulate in the first pipe130or the second pipe140, which still belongs to the scope of the invention. The driving element160is, for example, a pump, but the invention is not limited thereto.

Moreover, the heat dissipation module100aof the embodiment may further include two tanks170, which are respectively connected to the first pipe130and the second pipe140to accommodate the liquid medium F. The liquid medium F in the tanks170is by the driving elements160to circulate in the first pipe130and the second pipe140. In another embodiment that is not shown, a number of the tank170may be only one, which is connected to the first pipe130or the second pipe140, and the liquid medium F in the tank170is driven by the driving element160to circulate in the first pipe130or the second pipe140, which still belongs to the scope of the invention.

In order to improve the heat dissipation efficiency, at least a part of the first pipe130in the embodiment is heat sink accommodating slots132, and at least a part of the second pipe140is heat sink accommodating slots142. The first heat sources40a,40band the second heat sources50a,50b,50cand50drespectively contact the heat sink accommodating slots132,142, and the liquid medium F flows into the heat sink accommodating slots132,142for heat dissipation. The heat sink accommodating slots132and142may be respectively regarded as a kind of cold plate.

In brief, the heat dissipation module100aof the embodiment adopts two independent liquid cooling loops to respectively dissipate the heat of the first heat sources40a,40band the second heat sources50a,50b,50cand50dwith different operating temperatures, which achieves a better heat dissipation effect. Namely, the heat dissipation module100aof the embodiment may be effectively configured with liquid cooling according to a temperature resistance level, so that the heat sources may have a better heat dissipation effect to achieve more effective utilization of resources. In addition, the projection device10ausing the heat dissipation module100aof the embodiment adopts a liquid cooling heat dissipation system, and since the heat dissipation module100ais effectively configured with the heat sources, the heat dissipation area may be increased without increasing the number of fans, and under the condition that the heat dissipation efficiency is improved, a fan speed is reduced to reduce system noise.

It should be noticed that reference numbers of the components and a part of contents of the aforementioned embodiment are also used in the following embodiment, wherein the same reference numbers denote the same or like components, and descriptions of the same technical contents are omitted. The aforementioned embodiment may be referred for descriptions of the omitted parts, and detailed descriptions thereof are not repeated in the following embodiment.

FIG. 2is a schematic diagram of a projection device according to another embodiment of the invention. Referring toFIG. 1AandFIG. 2at the same time, the projection device10bof the embodiment is similar to the projection device10aof the aforementioned embodiment. A difference between the two projection devices10aand10bis that: in the embodiment, the fans150bof the heat dissipation module100bare arranged on one side of the first heat sink110relatively far away from the air inlet22, and the second heat sink120bis disposed corresponding to the air outlet24. Namely, the fans150bare arranged on one side of the first heat sink110, the first heat sink110and the second heat sink120bare arranged vertically, and the fans150bare arranged between the first heat sink110and the second heat sink120b.

FIG. 3is a schematic diagram of a projection device according to another embodiment of the invention. Referring toFIG. 1AandFIG. 3at the same time, the projection device10cof the embodiment is similar to the projection device10aof the aforementioned embodiment. A difference between the two projection devices10aand10cis that: in the embodiment, the fans150cof the heat dissipation module100cgenerates heat dissipation airflows, and in an airflow direction D3of the heat dissipation airflows, the first heat sink110is arranged upstream of the airflow direction D3compared to the second heat sink120c.In addition, compared to the second heat sink120c,the first heat sink110is closer to the air inlet22; on the contrary, compared to the first heat sink110, the second radiator120cis closer to the air outlet24.

In summary, the embodiments of the invention have at least one of following advantages or effects. In the design of the heat dissipation module of the invention, the first heat sink and the first heat source form the first loop through the first pipe, the second heat sink and the second heat source form the second circuit through the second pipe, and the liquid medium in the pipes flows through the heat sinks for heat exchange and then flows to the heat sources for circulating heat dissipation. In other words, by using two sets of independent liquid cooling loops to respectively dissipate heat of the first heat source and the second heat source with different operating temperatures, the heat dissipation module of the invention may have better heat dissipation efficiency. In addition, the projection device using the heat dissipation module of the invention may have increased heat dissipation area without increasing a number of fans, and may reduce a rotation speed of the fans, thereby reducing system noise.