CN218601668U - LCD projector sealing optical machine of indirect liquid cooling - Google Patents

Abstract

The utility model discloses an indirect liquid-cooled LCD projector sealing optical machine, which comprises a cooling system, an optical system and an optical machine shell; the cooling system comprises a water pump, an internal circulation heat exchanger, a light source heat absorber, a water tank and a flowmeter which are sequentially arranged in the flowing direction of liquid, and further comprises an external fan and an internal circulation fan; the water pump, the internal circulation heat exchanger, the light source heat absorber, the water tank and the flowmeter are connected in series to form a loop, so that a closed circulation flow channel is formed. The closed circulating flow channel is filled with cooling liquid; the outer fan is over against the water tank to blow or suck air. The utility model discloses it is little with the environmental temperature difference with radiating heat balance point to generate heat, and LCD light valve and optical material's temperature rise is little, is favorable to showing the heat-sinking capability that improves the ray apparatus, has prolonged product life, and the projector also allows the higher luminance of output simultaneously, has promoted the market synthesis competitiveness of product.

Description

LCD projector sealing optical machine of indirect liquid cooling

Technical Field

The utility model relates to a projector field especially relates to a sealed ray apparatus of LCD projector of indirect liquid cooling.

Background

The totally enclosed LCD projector optical machine (optical machine for short, the same is used later) is a more popular structural mode in the industry in recent years, and because the heat dissipation of the LCD light valve is generally an air cooling mode, the failure trouble caused by the deposition of dust on the surface of an optical device is obviously reduced after the optical system is sealed, and the service life of the optical device can be obviously improved.

The specific structure is that a closed circulating air duct (commonly known as an internal circulating air duct in the industry) is arranged in the optical machine, and the internal circulating air duct and the external atmosphere have certain air tightness. Also comprises an internal circulation fan, an internal circulation heat exchanger (a heat exchanger for short, the same applies hereinafter) and the like. The LCD light valve, the internal circulation fan and the heat exchanger are all arranged in the internal circulation air duct, the heat on the surface of the LCD light valve can be theoretically taken away through the operation of the internal circulation fan, and the heat of the air in the light machine is transferred and diffused into the atmosphere through the heat exchanger. The heating source or the preferential heat dissipation object in the optical machine is mainly an LCD light valve, and the cooling of the internal air mainly depends on a heat exchanger.

Under the current technical conditions, domestic LCD projectors have already gone beyond the 400Lm (lumen) major, because the transmittance of the LCD light valve is very low (about 5% -6% of natural light), and if a closed optical-mechanical technology is adopted, if the optical power corresponding to 400Lm is output and generates heat inside the optical-mechanical (mainly the LCD light valve), the existing air/air heat exchanger technology for the optical-mechanical, see fig. 8-11 (described later), can hardly provide effective heat dissipation for the LCD light valve of about 3-5 inches. Even under the premise of relaxing the noise and volume indexes to a certain degree. The key reason is that the heat is transferred from the heat absorption part of the heat exchanger, such as a 'of fig. 8, to the heat release part, such as b', which requires a great temperature difference, and the temperature difference is usually more than or equal to 30 ℃, which seriously affects the heat dissipation of the optical machine.

The key factor causing the light machine not to radiate heat effectively is that the radiating efficiency of the existing light machine is influenced by various objective factors which are restricted mutually, and the fundamental reason is that the heat transfer coefficient (which can be understood as the heat exchange coefficient to a certain extent) of the internal circulation air duct is limited by the current technical conditions or the definition of a single LCD projector product.

Because the temperature of the air inside the optical machine is as high as more than 60 ℃ after the optical machine is in a thermal equilibrium state, the main materials of the LCD light valve, the polarizer, the phenanthrene mirror, the optical machine shell (generally made of plastic) and the like of the projector are far higher than 60 ℃, usually more than or equal to 85-110 ℃, and the optical machine is burnt or failed. For the heat dissipation of the optical machine, the smaller the difference between the temperature value of the heat balance point and the ambient temperature is, the better the quality of the product is, and the more advanced and reliable the heat dissipation technology of the optical machine is. Therefore, the utility model provides an indirect liquid-cooled LCD projector sealing optical machine, its generate heat and radiating heat balance point and the environmental temperature difference are little, and the heat transfer capacity and each heat source temperature cascade ("hot cascade", the same after) effect all far superior to current air cooling technique, and comprehensive engineering adaptability is far superior to current gas/gas heat transfer technique and even uses initiative refrigeration technologies such as cold pump, is favorable to showing the heat-sinking capability etc. that improves the optical machine.

SUMMERY OF THE UTILITY MODEL

The utility model aims at overcoming the not enough of prior art, provide a sealed ray apparatus of LCD projector of indirect liquid cooling. The utility model discloses indirect liquid cooling's LCD projector sealing light machine is made simple relatively, the sexual valence relative altitude, it is little with radiating heat balance point and the environmental temperature difference to generate heat, the heat transfer capacity cascades with each source temperature that generates heat ("hot cascade", back with) the effect all is far superior to current air cooling technique, the integrated engineering adaptability is far superior to current gas/gas heat transfer technique or even uses initiative refrigeration techniques such as cold pump, LCD light valve and optical material's temperature rise is little, be favorable to showing the heat-sinking capability who improves the ray apparatus, extension product life, the projector also allows the higher luminance of output simultaneously, promote the market synthesis competitiveness of product.

In order to achieve the above object, the utility model provides a sealed ray apparatus of LCD projector of indirect liquid cooling, including cooling system, optical system and ray apparatus casing.

The cooling system comprises a water pump, an internal circulation heat exchanger, a light source heat absorber, a water tank and a flowmeter which are sequentially arranged in the flowing direction of liquid; the cooling system further comprises an outer fan and an inner circulating fan.

The water pump, the internal circulation heat exchanger, the light source heat absorber, the water tank with the flowmeter all is provided with one each water inlet and delivery port, the water pump, the internal circulation heat exchanger, the light source heat absorber, the water tank with the flowmeter links to each other in series and becomes the return circuit, forms closed circulation flow channel. And the closed circulating flow channel is filled with cooling liquid. The outer fan is over against the water tank to blow or suck air.

Further, the number of the water pump, the internal circulation heat exchanger, the water tank, the external fan and the internal circulation fan is one or more.

When the number of the water pumps, the internal circulation heat exchanger and the water tank is multiple, the water pumps, the internal circulation heat exchanger and the water tank are connected into the cooling system in series or in parallel.

Furthermore, the optical system comprises an LED light source, a condenser, a collimating lens, an LCD light valve, a field lens, an imaging reflector and a projection lens which are sequentially arranged according to the light advancing direction. The light source heat absorber is attached to the back face of the LED light source.

One end of the optical machine shell is provided with a light source mounting port, and the other end of the optical machine shell is provided with a lens mounting port; the LED light source and the projection lens are correspondingly arranged at the light source mounting opening and the lens mounting opening respectively.

The condenser, the collimating lens, the LCD light valve, the field lens, the imaging reflector, the internal circulation heat exchanger and the internal circulation fan are arranged in the optical machine shell. The water pump, the light source heat absorber, the water tank, the flowmeter and the outer fan are located outside the optical machine shell.

The inside of the optical machine shell is provided with a closed-loop circulating internal circulating air duct, and the LCD light valve, the internal circulating heat exchanger and the internal circulating fan are arranged in the internal circulating air duct; the water inlet and the water outlet of the internal circulation heat exchanger penetrate out of the optical machine shell.

Further, the internal circulation heat exchanger comprises a first collecting pipe, a second collecting pipe, a plurality of water channels and a plurality of fins; each water channel is flat, and the outer surface of the flow cross section is rectangular or oval.

The surface of the fin is of a wave-shaped structure.

When the number of the water channels is less than that of the fins, two adjacent fins are separated by one water channel, and the two opposite outer planes of any one water channel are respectively connected with the wave crest or the wave trough of the wave-shaped structure of the fin.

When the number of the water channels is larger than that of the fins, wave crests or wave troughs of the wave-shaped structure of the fins are connected between every two adjacent water channels.

The first collecting pipe is internally provided with a blocking wall, and the first collecting pipe is divided into two cavities which are not communicated through the blocking wall; the two cavities which are not communicated are a water inlet cavity and a water outlet cavity; the water inlet of the internal circulation heat exchanger is communicated with the water inlet cavity, and the water outlet of the internal circulation heat exchanger is communicated with the water outlet cavity.

One end of a part of water channels in the plurality of water channels is communicated with the water inlet cavity of the first collecting pipe; one end of the rest water channels in the plurality of water channels is communicated with the water outlet cavity of the first collecting pipe. The other ends of the water channels opposite to each other are communicated with the second collecting pipe;

and the cooling liquid flows into the water inlet cavity of the first collecting pipe through the water inlet of the internal circulation heat exchanger, is divided by the water inlet cavity, flows to the second collecting pipe through part of water channels in the plurality of water channels to be converged, further flows back to the water outlet cavity of the first collecting pipe through the rest water channels in the plurality of water channels, and flows out through the water outlet of the internal circulation heat exchanger.

Further, the internal circulation heat exchanger also comprises a framework; the first collecting pipe, the second collecting pipe, the plurality of water channels and the plurality of fins are installed in the framework after being assembled.

Preferably, the water pump, the internal circulation heat exchanger, the light source heat absorber, the water tank and the flowmeter are connected in series through water pipes, and the water pipes are environment-friendly silicone tubes.

The utility model discloses an actively the effect:

1. the cooling system of the utility model forms a closed circulation flow passage, and realizes the circulation of cooling liquid in the cooling system through the water pump, so that the internal circulation heat exchanger can effectively and quickly absorb the heat in the optical system, and realize the quick heat dissipation of the LCD light valve; and the light source heat absorber can effectively and quickly absorb the heat emitted by the LED light source, so that the effective and quick heat dissipation of the LED light source is realized, and meanwhile, the outer fan is used for blowing or sucking air to the water tank, so that the quick heat dissipation of cooling liquid in the water tank is realized, and the cooling effect of the cooling system is ensured. The utility model discloses the preparation is simple relatively, the sexual valence relative altitude, it is little with radiating heat balance point and the environmental temperature difference to generate heat, the heat transfer capacity cascades with each source temperature that generates heat ("thermal cascade", back with) the effect all is far superior to current air cooling technique, integrated engineering adaptability is far superior to current gas/gas heat transfer technique and uses initiative refrigeration techniques such as cold pump even, LCD light valve and optical material's temperature rise is little, be favorable to showing the heat-sinking capability who improves the ray apparatus, extension product life, the higher luminance of export is also allowed to the projector simultaneously, promote the market synthesis competitiveness of product.

2. Compared with the prior art, the heat exchanger (gas/gas heat exchange) with a gas (heat absorption)/conduction (partition plate)/gas (heat release) structure or the heat exchanger with a gas (heat absorption)/refrigeration/gas (heat release) structure is only arranged on the inner circulation air duct of the optical machine, and the heat exchanger only aims at the LED light source and is provided with a heat pipe radiator or an extruded section radiator to radiate the heat of the local and single points of the optical machine, the utility model discloses a light source heat absorber and a plurality of inner circulation heat exchangers, a plurality of inner circulation fans, a plurality of water tanks and a plurality of outer fans are arranged to radiate the heat of the projector sealing optical machine comprehensively and multipoint, so that the temperature value of the heat balance point of heating/radiating can be effectively reduced, the temperature rise of each heat source can be reduced as much as possible, and the optical machine has better quality;

3. compare prior art and set up the cooling (transport heat) mode of high-power consumption inefficient peltier element to the heat exchanger in internal circulation wind channel, the utility model discloses need not the extra high-power energy consumption that is used for peltier element, can effectively reduce the input electric power of projector, the energy saving is and be favorable to the whole heat dissipation of projector.

4. Because the heat removal ability of liquid is stronger, consequently the utility model discloses the heat source temperature cascade effect of different positions is superior to current air-cooled technique in the indirect liquid cooling system much more.

5. The specific heat capacity of the liquid is much larger than that of air, the temperature change speed of the heating element can be effectively reduced, and the reliability of the product can be remarkably improved.

6. The utility model discloses except that prior art accessible adjustment each fan rotational speed and obtain different radiating effect, can also realize through the rotational speed of adjustment water pump cooling system heat transfer rate's change makes projector cooling system work in more scientific efficient state.

7. The utility model discloses internal circulation heat exchanger compares current heat exchanger technique, has much higher unit volume heat transfer area (m) ² /m ³ ) The heat exchanger has the advantages of being small in size of a projector sealing light machine, or providing higher heat exchange coefficient for the internal circulation air duct, and playing a significant positive role.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments described in the present practical novel, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a schematic diagram of an embodiment of the present invention;

fig. 2 is another angle display diagram of the embodiment of the present invention;

fig. 3 is a diagram of an optical system according to an embodiment of the present invention;

fig. 4 is an illustration of the housing of the optical machine of the embodiment of the present invention taken away;

fig. 5 is an illustration of an internal circulation heat exchanger according to an embodiment of the present invention;

FIG. 6 is a partial cutaway view of FIG. 5;

FIG. 7 is a further shown view of FIG. 5;

FIG. 8 is a schematic view of a prior art FIN welded heat exchanger;

FIG. 9 is a schematic diagram of a conventional heat exchanger using heat pipes to transfer heat;

FIG. 10 is a schematic view of a conventional heat exchanger with a straight rib profile configuration;

fig. 11 is a schematic structural diagram of a conventional heat exchanger using a cold pump.

Detailed Description

In order to make the technical solution of the present invention better understood, the present invention is described in detail below with reference to the accompanying drawings, and the description of the present invention is only exemplary and explanatory, and should not be construed as limiting the scope of the present invention.

It should be noted that: like reference numerals refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.

It should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like refer to the orientation or positional relationship shown in the drawings, or the orientation or positional relationship that the utility model is usually placed when in use, and are used for convenience of description and simplification of description, but do not refer to or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and the like are used merely to distinguish one description from another, and are not to be construed as indicating or implying relative importance.

Furthermore, the terms "horizontal", "vertical", "overhang" and the like do not imply that the components are required to be absolutely horizontal or overhang, but may be slightly inclined. For example, "horizontal" merely means that the direction is more horizontal than "vertical" and does not mean that the structure must be perfectly horizontal, but may be slightly inclined.

In the description of the present invention, it should also be noted that, unless otherwise explicitly specified or limited, the terms "disposed," "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.

The embodiment is as follows:

referring to fig. 1-7, the present embodiment provides an indirect liquid-cooled LCD projector sealed optical engine, which includes a cooling system, an optical system and an optical engine housing 3.

The cooling system comprises a water pump 11, an internal circulation heat exchanger 12, a light source heat absorber 13, a water tank 14 and a flowmeter 18 which are sequentially arranged in the flowing direction of liquid (or cooling liquid, the same later); the cooling system also includes an outer fan 15 and an inner circulation fan 16.

The water pump 11, the internal circulation heat exchanger 12, the light source heat absorber 13, the water tank 14 and the flowmeter 18 are respectively provided with a water inlet and a water outlet. The water pump 11, the internal circulation heat exchanger 12, the light source heat absorber 13, the water tank 14 and the flowmeter 18 are connected in series to form a loop, so that a closed circulation flow channel is formed, and the inside of the closed circulation flow channel is filled with cooling liquid. The direction indicated by the arrow in fig. 1 is the liquid flow direction.

In this embodiment, the water pump 11, the internal circulation heat exchanger 12, the light source heat absorber 13, the water tank 14, and the water inlet and the water outlet on the flow meter 18 are preferably, but not limited to, pagoda joints. Wherein the internal circulation heat exchanger 12, the light source heat absorber 13, the pagoda joints (water inlet and water outlet) of the water tank 14 are preferably, but not limited to, connected with the structural bodies of the first manifold 121 (described later), the light source heat absorber 13 and the water tank 14 by brazing. The water pump 11 and the flow meter 18 are standard parts, generally plastic housings, so their respective water inlets and outlets, and their own structural bodies are often already injection molded as one piece.

In this embodiment, the water pump 11, the internal circulation heat exchanger 12, the light source heat absorber 13, the water tank 14 and the flow meter 18 are connected with each other through a water pipe, and the water inlets and the water outlets are arranged to facilitate connection of water pipes. The multi-section water pipe comprises a first water pipe 171 connected between the water outlet of the water pump 11 and the water inlet of the internal circulation heat exchanger 12; a second water pipe 172 connected between the water outlet of the internal circulation heat exchanger 12 and the water inlet of the light source heat absorber 13; a third water pipe 173 connected between the water outlet of the light source heat absorber 13 and the water inlet of the water tank 14; a fourth water pipe 174 connected between the water outlet of the water tank 14 and the water inlet of the flow meter 18; a fifth water pipe 175 connected between the outlet of the flow meter 18 and the inlet of the water pump 11. In this embodiment, the practical situations of the projector, such as environmental protection, power consumption, weather resistance and size, are considered, the inner diameter of the water pipe is preferably but not limited to 6mm-8mm, so that the technical requirements can be better met, and the water pipe is preferably made of an environment-friendly silicone tube, so that for a consumer, the pipeline cannot emit peculiar smell, and the experience satisfaction of the consumer is increased. Meanwhile, the position of the flow meter 18 may be installed before the water pump 11 or after the water pump 11, and the functions are different from each other.

The water pump 11, the first water pipe 171, the internal circulation heat exchanger 12, the second water pipe 172, the light source heat absorber 13, the third water pipe 173, the water tank 14, the fourth water pipe 174, the flow meter 18, and the fifth water pipe 175 are filled with a coolant in a flowing direction of the coolant. In the embodiment, the cooling liquid is preferably, but not limited to, an automobile antifreeze, such as FD-2 type automobile antifreeze of great wall company.

The outer fan 15 blows air or sucks air to the water tank 14. In this embodiment, the outer fan 15 blows air to the water tank 14. The size of the outer fan 15 is preferably, but not limited to, 120mm 25mm (standard model 12025) axial flow fan; the water tank 14 is preferably, but not limited to, a 120mm 30mm computer water-cooled drain.

In this embodiment, 40mm 12mm's computer water cooling head can be referred to light source heat absorber 13's structure, and the difference of computer water cooling head lies in need the preparation to be used for the installation on light source heat absorber 13 the screw hole of LED light source 21. These are the basic knowledge of the projector structure and will not be described further.

The number of the water pump 11, the internal circulation heat exchanger 12, the water tank 14, the external fan 15 and the internal circulation fan 16 is one or more; in this embodiment, the number of the water pump 11, the internal circulation heat exchanger 12, the water tank 14 and the external fan 15 is preferably, but not limited to, one, while the number of the internal circulation fan 16 is preferably, but not limited to, two, and the model is preferably, but not limited to, 5020 turbo fan, which just matches with the LCD light valve of 3.5 inches to 5 inches.

When the number of the water pump 11, the internal circulation heat exchanger 12 and the water tank 14 is multiple, the water pump, the internal circulation heat exchanger 12 and the water tank are connected into the cooling system in series or in parallel, which are the basic common knowledge of water and electricity in life and are not described again.

Referring to fig. 3, the optical system of the present embodiment includes an LED light source 21, a condenser 22, a collimating lens 23, an LCD light valve 24, a field lens 25, an imaging mirror 26, and a projection lens 27, which are sequentially arranged in a light traveling direction. In the present embodiment, the condenser 22 is preferably, but not limited to, a square cone condenser (commonly referred to in the industry as "scoop", "light pass", etc.). This optical system is the structure currently used by 99% of the LCD projectors in the industry. The light source heat sink 13 is attached to the back surface of the LED light source 21. In this embodiment, the size of the LCD light valve 24 is 4.5 inches, which can perfectly match with two 5020 turbo fans.

One end of the optical machine shell 3 is provided with a light source mounting port, and the other end of the optical machine shell is provided with a lens mounting port; the LED light source 21 and the projection lens 27 are correspondingly installed at the light source installation opening and the lens installation opening respectively, so that the complete sealing of the optical machine is realized.

The condenser 22, the collimating lens 23, the LCD light valve 24, the field lens 25, the imaging mirror 26, the internal circulation heat exchanger 12, and the internal circulation fan 16 are mounted inside the optical-mechanical housing 3. The water pump 11, the light source heat absorber 13, the water tank 14, the flow meter 18 and the external fan 15 are located outside the optical machine housing 3.

Referring to fig. 4, a closed-loop circulating internal circulation air duct 311 is disposed inside the optical-mechanical housing 3, and the LCD light valve 24, the internal circulation heat exchanger 12 and the internal circulation fan 16 are disposed in the internal circulation air duct 311; the air flow (see the arrow of "311" in the figure) flowing inside the internal circulation air duct 311 flows out from the air outlet of the internal circulation fan 16 (two air outlets installed in parallel), cools (dissipates heat) the LCD light valve 24, the air temperature rises, and further the hot air passes through the internal circulation heat exchanger 12 to be cooled and then returns to the air inlet of the internal circulation fan 16; the water inlet and the water outlet of the internal circulation heat exchanger 12 penetrate out of the optical machine housing 3 so as to be connected with the first water pipe 171 and the second water pipe 172. The internal circulation air duct 311 is a typical structure of a fully sealed optical machine in the industry, and the principle and the basic structure thereof are not described in detail.

Referring to fig. 5-7, the internal circulation heat exchanger 12 includes a first collecting pipe 121, a second collecting pipe 122, a plurality of water channels 123, and a plurality of fins 124; each water channel is flat, and the outer surface of the flow cross section is rectangular or oval.

The surface of the fin 124 is formed into a wave-shaped structure, which is very common on an engine radiator (water tank) of an automobile and an outdoor unit of an air conditioner, and has extremely low wind resistance, and the details are not repeated.

When the number of the water channels 123 is less than that of the fins 124, the adjacent fins 124 are separated by one water channel 123, and the two opposite outer planes of any one water channel 123 are respectively connected with the wave crest or the wave trough of the wave-shaped structure of one fin 124.

When the number of the water channels 123 is larger than that of the fins 124, a wave crest or a wave trough of the wave-shaped structure of one fin 124 is connected between two adjacent water channels 123.

Referring to fig. 7, the number of the water channels 123 in this embodiment is preferably, but not limited to, six, and the number of the fins 124 is preferably, but not limited to, five.

With continued reference to fig. 7, a blocking wall 1210 is disposed inside the first collecting pipe 121, and the first collecting pipe 121 is divided into two non-communicated cavities, namely, an inlet cavity 1211 and an outlet cavity 1212, by the blocking wall 1210; the water inlet of the internal circulation heat exchanger 12 is communicated with the water inlet cavity 1211, and the water outlet of the internal circulation heat exchanger 12 is communicated with the water outlet cavity 1212.

One end of a part of the water channels 123 (preferably, but not limited to, three) in the plurality of water channels 123 is communicated with the water inlet cavity 1211 of the first collecting pipe 121; one end of the remaining water channels 123 (preferably, but not limited to, the remaining three water channels 123) in the plurality of water channels 123 is communicated with the water outlet cavity 1212 of the first collecting pipe 121. The other end of the water channels 123 is communicated with the second collecting pipe 122.

The cooling liquid flows into the water inlet cavity 1211 of the first collecting pipe 121 through the water inlet of the internal circulation heat exchanger 12, is divided by the water inlet cavity 1211, flows to the second collecting pipe 122 through a part of the water channels 123 (for example, the three mentioned above) in the plurality of water channels 123 for converging, further flows back to the water outlet cavity 1212 of the first collecting pipe 121 through the remaining part of the water channels 123 (for example, the three mentioned above) in the plurality of water channels 123, and flows out through the water outlet of the internal circulation heat exchanger 12.

Specifically, when the hot air in the internal circulation air duct 311 passes through the internal circulation heat exchanger 12, the hot air is rapidly cooled by the cooling liquid flowing in the plurality of water channels 123, and the hot air is rapidly cooled by the plurality of fins 124. Under the combined action of the water channels 123 and the fins 124, the internal circulation heat exchanger 12 of the embodiment has a very high heat exchange area per unit volume, and plays a significant positive role in miniaturizing the sealed light engine of the projector or providing a higher heat exchange coefficient for the internal circulation air duct 311.

The internal circulation heat exchanger 12 further comprises a skeleton 125; the first collecting pipe 121, the second collecting pipe 122, the plurality of water channels 123 and the plurality of fins 124 are installed inside the framework 125 after being assembled (e.g., brazed). The frame 125 is used to properly mount the internal circulation heat exchanger 12 inside the optical engine housing 3 and to prevent fins from being damaged during raw material transportation and assembly (since the thickness of fins is typically only a few tens of microns).

The addition of the flow meter 18 to the cooling system is to ensure the functional reliability of the system. When the cooling system has faults such as liquid leakage, insufficient pressure, damage of the water pump 11 and the like, the flow meter 18 sends a signal (not shown in the figure) to a main control chip (a projector standard, such as MTK9255 and the like) of the projector so as to protect the projector from being damaged. Meanwhile, the flow meter 18 can be used as a flow acquisition signal to provide intelligent control parameter acquisition input for the main control chip. During concrete implementation, still can select to add many places temperature probe (not drawn in the picture) on cooling system to send into the main control chip of projector, and then through the rotational speed of each fan, the rotational speed of water pump 11 of adjustment, make the projector work in the optimum operating mode, increase cooling system's intellectuality, bring better experience sense for the consumer.

See fig. 8-11 for a more typical prior art heat exchanger technology for a fully sealed optical bench. Fig. 8 is a schematic structural diagram of a heat exchanger welded by using a FIN. In the figure, 41' is a partition plate, 42' is a heat absorbing portion, and 43' is a heat radiating portion. The heat absorbing part 42 'and the heat releasing part 43' of the heat exchanger are continuously punched FIN structures (generally, called as "FIN", an internal term) and welded on two opposite surfaces of the partition plate 41', the heat absorbing part 42' is arranged in the optical machine, the heat releasing part 43 'is arranged outside the optical machine, and the partition plate 41' separates the inside and the outside of the optical machine to realize air tightness, so that the heat exchanger has the advantages of high cost performance, portability and the like.

The disadvantages of this type of heat exchanger are mainly two major, firstly, the heat absorbing portion 42 'absorbs the heat of the air in the internal circulation air duct, and transfers the heat to the heat releasing portion 43' through the partition plate 41', and this process has a great thermal resistance, thereby bringing a great temperature difference, for example, the heat of the air in the internal circulation air duct is transferred from a' of the heat absorbing portion 42 'to b' of the heat releasing portion 43 'through the partition plate 41' in fig. 8, and the thermal resistance in this process is great, because the physical distance of a '-b' is long, and the thickness of the button FIN is usually less than or equal to 0.3mm-0.4mm; secondly, the wind resistance of the FIN structure is large, the pressure loss of the wind flow provided by the internal circulating fan is great, and the heat transfer efficiency of the heat exchanger is further reduced.

Fig. 9 is a schematic diagram of a conventional heat exchanger structure using heat pipes for heat transfer, which, in addition to a still large wind resistance, transfers the heat of the air in the internal circulation duct from the point a "of the heat absorbing portion 37 'to the heat pipe 36', and then from the heat pipe 36 'to the point b" of the heat releasing portion 38', and this process also has a very large thermal resistance, although the thermal conductivity of the heat pipe 36 'is approximately two orders of magnitude that of the partition plate 41' of the scheme in fig. 8, actually, the heat exchange effect of the schemes in fig. 8 and 9 on a specific product is often very slightly different. One is that the two ends of the heat pipe 36' have larger temperature difference (at least > 3 ℃) and the other is that the physical distance a "-b" is not shorter than that of the scheme in fig. 8, and the thickness of the heat absorbing part 37' and the heat releasing part 38' is not more than 0.3mm-0.4mm. In addition, this technical approach is also cost-competitive.

Fig. 10 is a schematic view of a conventional heat exchanger with a straight rib profile structure. Usually formed by two straight rib profile radiators 47', 48' which are attached back to back (also formed by aluminium alloy die-casting into a whole), and has the defects of heavy weight and unit volume heat exchange area (m) in addition to the defects of the heat exchanger ² /m ³ ) The minimal disadvantage, except that some low brightness (meaning low thermal power) products are suitable for use, has been phased out.

Fig. 11 is a schematic diagram of a conventional heat exchanger using a cold pump. In the figure, 49' is a peltier element, 50' is a heat absorbing portion, and 51' is a heat radiating portion. The technology obviously increases the total heat productivity of the projector, is still immature in the aspect of intelligent control, and has no better solution to the condensation phenomenon, so the industry is careful all the time, and the product carrying the technology is fresh.

With continued reference to figures 6 and 7,taking specific data to show the superiority of the present invention, taking the external dimension of the internal circulation heat exchanger 12 as 100mm 25mm 60mm as an example, the cross section of fig. 6 is 25mm 60mm, the maximum external area of the flow cross section of each water channel 123 is 1mm (usually 0.8mm to 1.2 mm) 25mm, the total area of the six water channels 123 is 6mm 25mm, and then the area occupied by the cross sections of the fins 124 is (60 to 6) mm to 25mm, and then the area occupied by any fin 124 is 10.8mm 25mm, when the hot air in the internal circulation air duct 311 passes through the fins 124, the distance from any point a on the fin to the point b on the water channel 123 is not more than 5.4mm, which greatly shortens the physical distance of heat transfer. After transferring heat to the water channel 123, the heat is carried away by the liquid inside the water channel 123 and eventually diffused into the atmosphere through the water tank 14. The a-b distances of the present invention are much shorter than the physical distances of a '-b', a "-b" in fig. 8-9. Meanwhile, the heat exchange area of the internal circulation heat exchanger 12 on the internal circulation air duct 311 can be calculated according to experience, and can easily break through 2000m ² /mm ³ . This is not possible at all for the prior art of fig. 8-11, and after considering the wind resistance, the heat exchange area per unit volume is often less than or equal to 1000m ² /mm ³ 。

The wavy structure of the surface of the fin 124 is beneficial to breaking the boundary layer of the fluid. Compared with the straight rib structure of fig. 8-11, the laminar flow effect is much better, so as to increase the heat transfer speed between the fins 124 and the air in the internal circulation air duct 311, which is the core of the totally enclosed optical engine that is expected to dissipate heat quickly.

It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

The principles and embodiments of the present invention have been explained herein using specific examples, and the above descriptions of examples are only used to help understand the method and its core ideas of the present invention. While the foregoing is only a preferred embodiment of the present invention, it should be noted that there are no specific structures that can be objectively infinite due to the limitation of the number expression, and it will be apparent to those skilled in the art that a number of modifications, decorations, or changes can be made without departing from the principle of the present invention, and the above technical features can also be combined in a suitable manner; the application of the concepts and technical solutions of the present invention to other applications, with or without any modifications, shall be considered as the scope of the present invention.

Claims (6)

1. An indirect liquid-cooled LCD projector sealed optical machine is characterized by comprising a cooling system, an optical system and an optical machine shell (3);

the cooling system comprises a water pump (11), an internal circulation heat exchanger (12), a light source heat absorber (13), a water tank (14) and a flowmeter (18) which are arranged in sequence in the flowing direction of liquid; the cooling system further comprises an outer fan (15) and an inner circulating fan (16);

the water pump (11), the internal circulation heat exchanger (12), the light source heat absorber (13), the water tank (14) and the flowmeter (18) are respectively provided with a water inlet and a water outlet, and the water pump (11), the internal circulation heat exchanger (12), the light source heat absorber (13), the water tank (14) and the flowmeter (18) are connected in series to form a loop to form a closed circulation flow channel; the closed circulating flow channel is filled with cooling liquid; the outer fan (15) is over against the water tank (14) for blowing or sucking.

2. The indirect liquid-cooled LCD projector sealing optical machine according to claim 1, wherein the number of the water pump (11), the internal circulation heat exchanger (12), the water tank (14), the external fan (15) and the internal circulation fan (16) is one or more;

when the number of the water pump (11), the internal circulation heat exchanger (12) and the water tank (14) is multiple, the water pump, the internal circulation heat exchanger and the water tank are connected into the cooling system in series or in parallel.

3. The indirect liquid-cooled LCD projector sealing optical machine according to claim 1, wherein the optical system comprises an LED light source (21), a condenser (22), a collimating lens (23), an LCD light valve (24), a field lens (25), an imaging mirror (26) and a projection lens (27) arranged in sequence along the light traveling direction; the light source heat absorber (13) is attached to the back surface of the LED light source (21);

one end of the optical machine shell (3) is provided with a light source mounting port, and the other end of the optical machine shell is provided with a lens mounting port; the LED light source (21) and the projection lens (27) are respectively and correspondingly arranged at the light source mounting opening and the lens mounting opening;

the condenser (22), the collimating lens (23), the LCD light valve (24), the field lens (25), the imaging reflector (26), the internal circulation heat exchanger (12) and the internal circulation fan (16) are arranged in the optical-mechanical shell (3); the water pump (11), the light source heat absorber (13), the water tank (14), the flow meter (18) and the outer fan (15) are positioned outside the optical machine shell (3);

an inner circulating air duct (311) which is closed-loop and circulates is arranged inside the optical machine shell (3), and the LCD light valve (24), the inner circulating heat exchanger (12) and the inner circulating fan (16) are arranged in the inner circulating air duct (311); the water inlet and the water outlet of the internal circulation heat exchanger (12) penetrate out of the optical machine shell (3).

4. The indirect liquid cooled LCD projector sealing optical machine of claim 1, wherein the internal circulation heat exchanger (12) comprises a first manifold (121), a second manifold (122), a plurality of water channels (123), a plurality of fins (124); each water channel is flat, and the outer surface of the overflowing cross section is rectangular or oval;

the surface of the fin (124) is in a wave-shaped structure;

when the number of the water channels (123) is less than that of the fins (124), two adjacent fins (124) are separated by one water channel (123), and two opposite outer planes of any one water channel (123) are respectively connected with the wave crest or the wave trough of the wave-shaped structure of one fin (124);

when the number of the water channels (123) is more than that of the fins (124), wave crests or wave troughs of the wave-shaped structure of one fin (124) are connected between two adjacent water channels (123);

a blocking wall (1210) is arranged inside the first collecting pipe (121), and the first collecting pipe (121) is divided into two cavities which are not communicated through the blocking wall (1210); the two cavities which are not communicated are a water inlet cavity (1211) and a water outlet cavity (1212); the water inlet of the internal circulation heat exchanger (12) is communicated with the water inlet cavity (1211), and the water outlet of the internal circulation heat exchanger (12) is communicated with the water outlet cavity (1212);

one end of a part of water channels (123) in the water channels (123) is communicated with the water inlet cavity (1211) of the first collecting pipe (121); one end of the rest water channels (123) in the water channels (123) is communicated with the water outlet cavity (1212) of the first collecting pipe (121); the other ends of the water channels (123) are communicated with the second collecting pipe (122);

the cooling liquid flows into the water inlet cavity (1211) of the first collecting pipe (121) through the water inlet of the internal circulation heat exchanger (12), is divided through the water inlet cavity (1211), flows to the second collecting pipe (122) through a part of water channels (123) in the plurality of water channels (123) to be converged, further flows back to the water outlet cavity (1212) of the first collecting pipe (121) through the rest water channels (123) in the plurality of water channels (123), and flows out through the water outlet of the internal circulation heat exchanger (12).

5. The indirect liquid-cooled LCD projector seal light engine of claim 4, wherein the internal recycle heat exchanger (12) further comprises a skeleton (125); the first collecting pipe (121), the second collecting pipe (122), the plurality of water channels (123) and the plurality of fins (124) are installed inside the framework (125) after being assembled.

6. The indirect liquid-cooled LCD projector sealing optical machine according to claim 1, wherein the water pump (11), the internal circulation heat exchanger (12), the light source heat absorber (13), the water tank (14) and the flow meter (18) are connected in series through water pipes, and the water pipes are environment-friendly silicone tubes.

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