Closed ray machine using helium for heat dissipation and temperature control and LCD projector

Abstract

The invention relates to a closed light machine using helium for heat dissipation and temperature control and an LCD projector. The closed light machine comprises a light machine shell, an internal circulation fan unit, a heat dissipation module and a control assembly. A first containing cavity and a second containing cavity are formed in the light machine shell, the imaging module comprises a first lens, an LCD screen, a second lens and a reflective mirror which are sequentially arranged along a light propagation path, the internal circulation fan set comprises a first internal circulation fan and a second internal circulation fan, and the heat dissipation module comprises a first heat dissipation device and a second heat dissipation device. The control assembly comprises a main control board, a first temperature sensor, a second temperature sensor and a helium concentration detector, the first temperature sensor, the second temperature sensor and the helium concentration detector are electrically connected to the main control board, the closed light machine obtains more reasonable air flow circulation and has the advantage of large air volume, the light machine shell is filled with helium, and the helium concentration detector is arranged in the light machine shell. Helium is used as high-heat-conduction gas, the effect of more rapid and sufficient heat exchange can be achieved, and the control assembly can adjust the rotating speed of the draught fan in real time according to temperature and helium concentration data.

Description

Technical Field

[0001] The present invention relates to the technical field of LCD projectors, and particularly to a sealed optical engine and an LCD projector that apply helium for heat dissipation and temperature control. Background Art

[0002] The LCD optical engine (i.e., the projection optical engine) is the most important component in an LCD projector. During the operation of the LCD optical engine, the LCD screen absorbs a large amount of heat. Therefore, forced cooling and heat dissipation are required for the LCD screen. According to the heat dissipation type, the LCD optical engine is mainly divided into two types, namely, a sealed optical engine and an open optical engine.

[0003] The sealed optical engine can effectively prevent dust and pollutants from entering the optical path, thereby significantly reducing the impact of dust on the LCD screen, enabling the projection device to be more widely adapted to various usage scenarios, and also being able to greatly extend the service life of the projection device. However, the enclosed environment brings great difficulties to the heat dissipation of the internal optical components of the optical engine. How to efficiently transfer the internal heat out without damaging the enclosed space is the key point of the current optical engine heat dissipation.

[0004] Currently, the heat dissipation method of the sealed optical engine can only transfer heat to the radiator through the internal circulation flow field, then conduct it to the outside through the radiator, and finally take away the heat by the external flow field. Therefore, the size of the internal circulation air volume of the optical engine is the key to heat dissipation. To ensure the compactness and aesthetics of the optical engine structure, the heat dissipation components need to be arranged around the optical components and occupy as little space as possible. In this case, a reasonable air duct design is required to ensure the air volume. In particular, in high-brightness models, due to the limitation of the structural space, it is impossible to place a large-sized fan, and multiple internal circulation fans often need to be placed in different gaps to meet the requirements. However, when two fans work simultaneously in a narrow internal circulation flow field, if the air duct is not reasonably designed, on the one hand, the flow field will become extremely chaotic, making it difficult to accurately simulate the internal flow field and increasing the difficulty of heat dissipation design; on the other hand, the two fans often do negative work on each other locally, increasing the fan impedance to each other, increasing noise and weakening the air volume. Summary of the Invention

[0005] Based on this, the purpose of the present invention is to overcome the deficiencies of the prior art and provide a sealed optical engine and an LCD projector that apply helium for heat dissipation and temperature control.

[0006] To achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0007] A sealed optical engine that applies helium for heat dissipation and temperature control, which includes: an optical engine housing, an internal circulation fan group, a heat dissipation module, and a control component;

[0008] A first accommodation cavity and a second accommodation cavity are formed in the optical machine housing at an upper and lower interval. The first accommodation cavity communicates with the second accommodation cavity through a first ventilation port and a second ventilation port. Helium gas is filled in the first accommodation cavity and the second accommodation cavity. A partition member and an imaging module are arranged in the first accommodation cavity;

[0009] The imaging module includes a first lens, an LCD screen, a second lens, and a reflector arranged in sequence along the light propagation path. The partition member, the LCD screen, the second lens, and the reflector together divide the first accommodation cavity into a first heat dissipation air duct, a second heat dissipation air duct, a first air passing cavity, and a second air passing cavity. The first heat dissipation air duct and the second heat dissipation air duct are respectively located on opposite sides of the LCD screen. The right ends of the first heat dissipation air duct and the second heat dissipation air duct communicate with the first air passing cavity, and the left ends of the first heat dissipation air duct and the second heat dissipation air duct communicate with the second air passing cavity. The first ventilation port is arranged corresponding to the position of the first heat dissipation air duct. A part of the second ventilation port communicates with the first air passing cavity, and another part of the second ventilation port communicates with the second air passing cavity;

[0010] The internal circulation fan group includes a first internal circulation fan and a second internal circulation fan. The first internal circulation fan is arranged in the second accommodation cavity and is used to output gas toward the first ventilation port. The second internal circulation fan is arranged in the second air passing cavity and is used to output gas toward the second heat dissipation air duct. Both the first internal circulation fan and the second internal circulation fan are internally provided with rotational speed sensors;

[0011] The heat dissipation module includes a first radiator and a second radiator. The first radiator includes a first cold end and a first hot end connected to conduct heat. The second radiator includes a second cold end and a second hot end connected to conduct heat. The first cold end is arranged in the second accommodation cavity, the second cold end is arranged in the second air passing cavity, and the first hot end and the second hot end both face the outside of the optical machine housing;

[0012] The control component includes a main control board and a first temperature sensor, a second temperature sensor, and a helium concentration detector electrically connected to the main control board. The main control board is also electrically connected to the first internal circulation fan and the second internal circulation fan. The first temperature sensor is used to detect the first temperature data of the first heat dissipation air duct. The second temperature sensor is used to detect the second temperature data of the second heat dissipation air duct. The helium concentration detector is used to detect the current helium concentration data in the first accommodation cavity. The main control board is used to adjust the rotational speeds of the first internal circulation fan and the second internal circulation fan according to the first temperature data, the second temperature data, and the current helium concentration.

[0013] As can be seen from the above, the enclosed optical engine of the present application obtains a more reasonable air flow circulation through the design of the heat dissipation channels, the positions of each fan and the radiator. The air flow circulation is faster, with the advantage of a large air volume, making the internal flow field of the optical engine housing relatively orderly, facilitating accurate simulation of the flow field, being conducive to more precise heat dissipation design, ultimately improving the heat dissipation efficiency of the enclosed optical engine, reducing the overall power consumption and volume of the enclosed optical engine, and ensuring the safe and stable operation of the enclosed optical engine. Moreover, the inside of the optical engine housing is filled with helium. As a gas with high thermal conductivity, helium can achieve a faster and more sufficient heat exchange effect, further improving the overall heat dissipation efficiency and ensuring the high-efficiency heat dissipation requirements of the imaging module, especially the LCD screen. In addition, the present embodiment also provides a control component, which can adjust the rotation speed of the fan in real time according to the temperature and helium concentration data, ensuring the balance between noise and heat dissipation efficiency and having higher practicability.

[0014] As an implementation manner, the adjustment method of the main control board includes:

[0015] Set the initial rotation speeds of the first internal circulation fan and the second internal circulation fan as N1, set the initial helium concentration data of the first accommodation cavity as P1, set the heat dissipation rate at the initial rotation speed N1 and the initial helium concentration data P1 as A1, and set the safety temperature threshold as T1;

[0016] Obtain the current helium concentration data P2, and output the heat dissipation rate A2 at the initial rotation speed N1 and the current helium concentration data P2, A2 = (P2 / P1) × A1;

[0017] Obtain the first temperature data T2. If T2 is greater than T1, then adjust the rotation speed of the first internal circulation fan to N2, N2 = ((A1 - A2) / A1 + 1) × N1 + ((T2 - T1) / T1) × N1;

[0018] Obtain the second temperature data T3. If T3 is greater than T1, then adjust the rotation speed of the second internal circulation fan to N3, N3 = ((A1 - A2) / A1 + 1) × N1 + ((T3 - T1) / T1) × N1.

[0019] As an implementation manner, the optical engine housing includes a top shell, a middle shell, and a bottom shell connected in sequence from top to bottom. The top shell and the middle shell jointly enclose the first accommodation cavity, the bottom shell and the bottom of the middle shell jointly enclose the second accommodation cavity, and the bottom of the middle shell is provided with the first ventilation opening and the second ventilation opening.

[0020] As an implementation manner, a sealing groove is provided around the top edge of the middle shell, a sealing ring is arranged in the sealing groove, and the top shell and the middle shell cooperate to tightly press the sealing ring.

[0021] As an implementation manner, a heat dissipation installation opening is provided on the side wall of the middle shell corresponding to the second air passing cavity, the second radiator is installed in the heat dissipation installation opening, and the second cold end faces the second air passing cavity.

[0022] As an implementation manner, a flow guiding plate is provided between the right ends of the first heat dissipation air duct and the second heat dissipation air duct, and the flow guiding plate is used for separating the air discharged from the first heat dissipation air duct and the second heat dissipation air duct.

[0023] As an implementation manner, the enclosed optical engine further includes a light source module, the light source module includes an LED light source, a light funnel and a light funnel housing, an opening is formed on the side wall of the middle shell corresponding to the LCD screen, the light funnel housing is installed at the opening, the light funnel is arranged in the light funnel housing, the light outlet of the light funnel faces the LCD screen, and the light inlet of the light funnel is arranged at the LED light source.

[0024] As an implementation manner, the enclosed optical engine further includes an LED radiator, the LED radiator includes a third cold end and a third hot end that are connected to conduct heat, and the third cold end is attached to the LED light source.

[0025] As an implementation manner, the enclosed optical engine further includes an external circulation fan group, the external circulation fan group includes a first external circulation fan and a second external circulation fan with the same air outlet direction, and the first hot end and the third hot end are both arranged at the air outlets of the first external circulation fan and the second external circulation fan.

[0026] An LCD projector according to the present application includes: a projection housing and the enclosed optical engine as described above provided in the projection housing.

[0027] For better understanding and implementation, the present invention will be described in detail below with reference to the accompanying drawings. Description of the Drawings

[0028] Figure 1 It is a schematic structural diagram of the enclosed optical engine in the embodiment of the present application;

[0029] Figure 2 It is an exploded structural diagram of the enclosed optical engine in the embodiment of the present application;

[0030] Figure 3 It is a side sectional view of the enclosed optical engine when the top shell is removed in the embodiment of the present application;

[0031] Figure 4 It is a top view of the enclosed optical engine when the top shell is removed in the embodiment of the present application;

[0032] Figure 5 For Figure 3Schematic diagram of the gas flow driven by the first internal circulation fan in the perspective view;

[0033] Figure 6 For Figure 4 Schematic diagram of the gas flow on the left side of the first heat dissipation air duct in the perspective view;

[0034] Figure 7 For Figure 4 Schematic diagram of the gas flow on the right side of the first heat dissipation air duct in the perspective view;

[0035] Figure 8 Schematic diagram of the structure of the LCD projector in the embodiment of the present application;

[0036] Description of the reference numerals:

[0037] 11. Top shell; 12. Middle shell; 121. First ventilation opening; 122. Second ventilation opening; 123. Sealing groove; 124. Heat dissipation installation opening; 13. Bottom shell; 141. First heat dissipation air duct; 142. Second heat dissipation air duct; 143. First air passing cavity; 144. Second air passing cavity; 15. Second accommodation cavity; 16. Partition member; 17. Deflector; 21. First lens; 22. Heat insulation glass; 23. LCD screen; 24. Second lens; 25. Reflecting mirror; 31. First internal circulation fan; 32. Second internal circulation fan; 41. First radiator; 411. First hot end; 412. First cold end; 42. Second radiator; 421. Second hot end; 422. Second cold end; 51. First external circulation fan; 52. Second external circulation fan; 61. LED light source; 62. Light funnel; 63. Light funnel housing; 64. LED radiator; 7. Projection lens; 81. Projection housing; 82. External circulation housing; 91. Main control board; 92. First temperature sensor; 93. Second temperature sensor; 94. Helium concentration detector. Detailed implementation manners

[0038] To further illustrate the embodiments, the present invention provides drawings. These drawings are part of the disclosure of the present invention, mainly used to illustrate the embodiments, and can be used in conjunction with the relevant descriptions in the specification to explain the operating principles of the embodiments. With reference to these contents, those of ordinary skill in the art should be able to understand other possible embodiments and the advantages of the present invention.

[0039] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "left", "right", "top", "bottom", "inner", "outer", "axial", "radial", "circumferential", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying 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 a limitation to the present invention.

[0040] Please refer to Figures 1 to 7 , this embodiment provides a hermetic optical engine applying helium for heat dissipation and temperature control, which includes: an optical engine housing, an internal circulation fan group, a heat dissipation module, and a control component;

[0041] A first accommodation cavity and a second accommodation cavity 15 are formed in the optical engine housing at intervals up and down. The first accommodation cavity communicates with the second accommodation cavity 15 through a first ventilation port 121 and a second ventilation port 122. Specifically, the optical engine housing of this embodiment includes a top shell 11, a middle shell 12, and a bottom shell 13 that are sequentially connected from top to bottom. The top shell 11 and the middle shell 12 jointly enclose the first accommodation cavity. The bottom shell 13 and the bottom of the middle shell 12 jointly enclose the second accommodation cavity 15. The bottom of the middle shell 12 is provided with the above-mentioned first ventilation port 121 and second ventilation port 122. Among them, the top shell 11 has a plate-like structure, and both the middle shell 12 and the bottom shell 13 are basin-like structures with upward openings. The top shell 11 covers the opening of the middle shell 12 to jointly enclose the first accommodation cavity with the middle shell 12. The opening of the bottom shell 13 is butted against the bottom of the middle shell 12 to jointly enclose the second accommodation cavity 15. A partition member 16 and an imaging module are arranged in the first accommodation cavity.

[0042] Preferably, helium is filled in the first accommodation cavity and the second accommodation cavity 15. As an inert gas, helium is colorless, odorless, and has stable chemical properties. It can not only meet the requirements of the optical light path, but also play a better protective role for the internal optical devices compared with the impurities in the air. The specific heat capacity of air is about 1.006 J / (g·K), while the specific heat capacity of helium is about 5.193 J / (g·K), which is about 5.16 times that of air. According to the specific heat capacity formula Q = cm△t, where Q represents the absorbed and released heat, c represents the specific heat capacity, and △t represents the temperature rise of the device, this means that under the same mass and other conditions, helium can absorb and release more heat than air. The thermal conductivity of helium is about 0.144 W / (m·K), while the thermal conductivity of air is 0.0233 W / (m·K), and the thermal conductivity is about 6.18 times that of air, which means that helium transfers heat faster than air. Therefore, in a sealed cavity, compared with air, helium as a high thermal conductivity gas can achieve faster heat transfer and uniform heat dissipation.

[0043] The imaging module includes a first lens 21, an LCD screen 23, a second lens 24, and a reflector 25 arranged in sequence along the light propagation path. Among them, the first lens 21 is a rear Fresnel lens, the second lens 24 is a front Fresnel lens. The separator 16 may include structures such as a partition plate and an LCD mounting bracket, as long as it can achieve the effect of separation. The separator 16, the LCD screen 23, the second lens 24, and the reflector 25 together divide the first accommodation cavity into a first heat dissipation air duct 141, a second heat dissipation air duct 142, a first air passing cavity 143, and a second air passing cavity 144. The first heat dissipation air duct 141 and the second heat dissipation air duct 142 are respectively located on opposite sides of the LCD screen 23. In this embodiment, the first heat dissipation air duct 141 and the second heat dissipation air duct 142 are left-right communicating channels. Among them, the right ends of the first heat dissipation air duct 141 and the second heat dissipation air duct 142 are both communicated with the first air passing cavity 143, the left ends of the first heat dissipation air duct 141 and the second heat dissipation air duct 142 are both communicated with the second air passing cavity 144. The first ventilation opening 121 is arranged corresponding to the position of the first heat dissipation air duct 141. A part of the second ventilation opening 122 is communicated with the first air passing cavity 143, and another part of the second ventilation opening 122 is communicated with the second air passing cavity 144.

[0044] The internal circulation fan group includes a first internal circulation fan 31 and a second internal circulation fan 32. The first internal circulation fan 31 is arranged in the second accommodation cavity 15 and is used to output gas toward the first ventilation opening 121. The second internal circulation fan 32 is arranged in the second air passing cavity 144 and is used to output gas toward the second heat dissipation air duct 142. Both the first internal circulation fan 31 and the second internal circulation fan 32 are internally provided with rotational speed sensors. Through the above settings, when the first internal circulation fan 31 and the second internal circulation fan 32 are started, the airflow can be driven to circulate in the optical machine housing, thereby driving the heat of the LCD screen 23. Specifically, as Figure 5 shown, Figure 5 the black arrows in represent the gas flow path. The first internal circulation fan 31 sucks the gas from the second ventilation opening 122 and outputs the gas toward the first ventilation opening 121. This gas enters the first heat dissipation air duct 141 to cool one side of the LCD screen 23, and then is divided into two parts, namely the right-side gas and the left-side gas. Among them, as Figure 7 shown, Figure 7 the black arrows in represent the gas flow path. The right-side gas enters the first air passing cavity 143 and is then sucked into the second ventilation opening 122 and continues to be conveyed by the first internal circulation fan 31. In addition, as Figure 6 shown, Figure 6The black arrows represent the gas flow paths. The gas on the left enters the second air passage cavity 144. The gas on the left continues to be divided into two parts. One part of the gas on the left is directly sucked into the second ventilation opening 122 and continues to be conveyed by the first internal circulation fan 31. The remaining part of the gas on the left is sucked by the second internal circulation fan 32 and then output to the second heat dissipation air duct 142 to cool the other side of the LCD screen 23. Subsequently, it enters the first air passage cavity 143 and is sucked into the second ventilation opening 122 and continues to be conveyed by the first internal circulation fan 31.

[0045] As can be seen from the above, based on the design of the above channels, the first internal circulation fan 31 and the second internal circulation fan 32 cooperate to continuously drive the air flow to circulate in the optical machine housing. The air flow passes through the first heat dissipation air duct 141 and the second heat dissipation air duct 142 formed on the opposite sides of the LCD screen 23, effectively dissipating heat from the opposite sides of the LCD screen 23 and greatly improving the heat dissipation efficiency.

[0046] The heat dissipation module includes a first radiator 41 and a second radiator 42. The first radiator 41 includes a first cold end 412 and a first hot end 411 that are connected to conduct heat. The second radiator 42 includes a second cold end 422 and a second hot end 421 that are connected to conduct heat. The first cold end 412 is disposed in the second accommodation cavity 15. The second cold end 422 is disposed in the second air passage cavity 144. The first hot end 411 and the second hot end 421 both face the outside of the optical machine housing. The first cold end 412 can provide a cold source for the second accommodation cavity 15 and absorb the heat of the high-temperature gas. The second cold end 422 can provide a cold source for the second air passage cavity 144 and absorb the heat of the high-temperature gas, so that the temperature of the gas circulating inside the optical machine housing can be effectively reduced. The first hot end 411 and the second hot end 421 face the outside of the optical machine housing and exchange heat with the external air to ensure that the cold ends are in a low-temperature state.

[0047] The control component includes a main control board 91, a first temperature sensor 92, a second temperature sensor 93, and a helium concentration detector 94 that are electrically connected to the main control board 91. The main control board 91 is also electrically connected to the first internal circulation fan 31 and the second internal circulation fan 32. The first temperature sensor 92 is used to detect the first temperature data of the first heat dissipation air duct 141, the second temperature sensor 93 is used to detect the second temperature data of the second heat dissipation air duct 142, the helium concentration detector 94 is used to detect the current helium concentration data in the first accommodation cavity, and the main control board 91 is used to adjust the rotation speeds of the first internal circulation fan 31 and the second internal circulation fan 32 according to the first temperature data, the second temperature data, and the current helium concentration. By setting the control component, the rotation speeds of the first internal circulation fan 31 and the second internal circulation fan 32 can be adjusted in real time according to the temperatures on the relative two sides of the LCD screen 23 and the current helium concentration, ensuring that their rotation speeds are within a reasonable range, which not only ensures the heat dissipation efficiency but also suppresses the generation of noise as much as possible, making the operation of the whole machine more reasonable.

[0048] As can be seen from the above, through the position design of the heat dissipation channels, each fan and the radiator in the closed optical engine according to the embodiments of the present application, a more reasonable air flow circulation is obtained. The air flow circulation is more rapid, with the advantage of a large air volume, making the internal flow field of the optical engine housing relatively orderly, facilitating the accurate simulation of the flow field, being conducive to more precise heat dissipation design, ultimately improving the heat dissipation efficiency of the closed optical engine, reducing the overall power consumption and volume of the closed optical engine, and ensuring the safe and stable operation of the closed optical engine. And the inside of the optical engine housing is filled with helium, and helium, as a gas with high thermal conductivity, can achieve a faster and more sufficient heat exchange effect, further improving the overall heat dissipation efficiency and ensuring the high-efficiency heat dissipation requirements of the imaging module, especially the LCD screen 23. In addition, this embodiment also provides a control component, which can adjust the rotation speed of the fan in real time according to the temperature and helium concentration data, ensuring the balance between noise and heat dissipation efficiency and having higher practicability.

[0049] Specifically, in this embodiment, the first temperature sensor 92 is disposed in the first heat dissipation air duct 141, the second temperature sensor 93 is disposed in the second heat dissipation air duct 142, and the helium concentration detector 94 is disposed between the first air passing cavity 143 and the second air passing cavity 144. The main control board 91 is disposed outside the optical engine housing. The main control board 91 can be a common existing control circuit board, which includes structures such as a microprocessor, a memory, an input-output interface, and various control logic circuits, and realizes functions such as outputting control signals according to input data, which will not be elaborated here.

[0050] Preferably, in this embodiment, the adjustment method of the main control board 91 includes:

[0051] S1: Set the initial rotational speeds of the first internal circulation fan 31 and the second internal circulation fan 32 as N1, set the initial helium concentration data of the first accommodating cavity as P1, set the heat dissipation rate at the initial rotational speed N1 and the initial helium concentration data P1 as A1, and set the safety temperature threshold as T1;

[0052] S2: Obtain the current helium concentration data P2, and output the heat dissipation rate A2 at the initial rotational speed N1 and the current helium concentration data P2, where A2 = (P2 / P1) × A1; it should be noted that the current helium concentration data P2 ≤ P1. When the light engine housing has good airtightness, external air will not enter the interior of the light engine housing. At this time, P2 = P1. When the airtightness of the light engine housing is poor, external air will enter the interior of the light engine housing. At this time, P2 < P1, which will affect the magnitude of A2. At this time, A2 < A1.

[0053] S3: Obtain the first temperature data T2. If T2 is greater than T1, then adjust the rotational speed of the first internal circulation fan 31 to N2, where N2 = ((A1 - A2) / A1 + 1) × N1 + ((T2 - T1) / T1) × N1;

[0054] S4: Obtain the second temperature data T3. If T3 is greater than T1, then adjust the rotational speed of the second internal circulation fan 32 to N3, where N3 = ((A1 - A2) / A1 + 1) × N1 + ((T3 - T1) / T1) × N1.

[0055] It should be noted that N1, P1, A1, and T1 are all data set in the main control board 91 at the time of factory shipment. In the normal state without adjustment by the main control board 91, when the first internal circulation fan 31 and the second internal circulation fan 32 are started, their rotational speeds are N1. And P1 is equal to the helium concentration filled into the interior of the light engine housing. A1 is the degree of temperature drop per unit time when the rotational speed of the fan remains at N1 and the helium concentration is P1. This value A1 can be obtained through measurement and is a fixed value. T1 is the safety temperature value of the LCD screen 23.

[0056] From the above adjustment method, it can be seen that the control component in this embodiment can adjust the rotational speeds of the first internal circulation fan 31 and the second internal circulation fan 32 in real time according to the first temperature data, the second temperature data, and the current helium concentration data, so as to ensure the balance between heat dissipation efficiency and noise control.

[0057] Further, in order to ensure that the helium concentration remains at the initial concentration for a long time, a sealing groove 123 is provided around the top edge of the middle shell 12 in this embodiment. A sealing ring is provided in the sealing groove 123, and the top shell 11 and the middle shell 12 cooperate to tightly press the sealing ring. By setting it in this way, the overall sealing performance can be improved, making it difficult for external air to enter the optical machine housing, ensuring that the helium concentration remains at the initial concentration, and ensuring the heat dissipation efficiency.

[0058] Preferably, a heat dissipation installation opening 124 is provided on the side wall of the middle shell 12 corresponding to the second air passage chamber 144. The second radiator 42 is installed in the heat dissipation installation opening 124, and the second cold end 422 faces the second air passage chamber 144. By setting it in this way, the occupied space of the second radiator 42 can be reduced.

[0059] Specifically, in this embodiment, the first heat dissipation air passage 141 is located between the LCD screen 23 and the first lens 21, and the second heat dissipation air passage 142 is located between the LCD screen 23 and the second lens 24.

[0060] Preferably, a flow guide plate 17 is provided between the right ends of the first heat dissipation air passage 141 and the second heat dissipation air passage 142. The flow guide plate 17 is used to separate the air discharged from the first heat dissipation air passage 141 and the second heat dissipation air passage 142, avoiding air flow disorder and avoiding backflow.

[0061] Preferably, the enclosed optical machine further includes a light source module. The light source module includes an LED light source 61, a light funnel 62, and a light funnel housing 63. An opening is provided on the side wall of the middle shell 12 corresponding to the LCD screen 23. The light funnel housing 63 is installed at the opening. The light funnel 62 is provided in the light funnel housing 63. The light outlet of the light funnel 62 faces the LCD screen 23, and the light inlet of the light funnel 62 is provided at the LED light source 61. The imaging module further includes a heat insulation glass 22 located in the first heat dissipation air passage 141. The enclosed optical machine further includes a projection lens 7, and a reflecting mirror 25 is used to reflect the light emitted from the second lens 24 to the projection lens 7. Thus, the light emitted by the LED light source 61 passes through the light funnel 62, the first lens 21, the heat insulation glass 22, the LCD screen 23, the second lens 24, and the reflecting mirror 25 in sequence and then is emitted from the projection lens 7 to form a projection image.

[0062] Preferably, the enclosed optical machine in this embodiment further includes an LED radiator 64. The LED radiator 64 includes a third cold end and a third hot end that are connected to conduct heat. The third cold end is attached to the LED light source 61 to dissipate heat from the LED light source 61, so as to effectively ensure the normal operation of the LED light source 61 and extend the service life of the LED light source 61.

[0063] Preferably, the enclosed optical engine of this embodiment further includes an external circulation fan group. The external circulation fan group includes a first external circulation fan 51 and a second external circulation fan 52 with the same air outlet direction. The first hot end 411 and the third hot end are both arranged at the air outlets of the first external circulation fan 51 and the second external circulation fan 52. The first external circulation fan 51 and the second external circulation fan 52 blow air to the first hot end 411 and the third hot end to control their temperatures. Among them, the enclosed optical engine further includes an external circulation housing 82. The external circulation housing 82 covers the first hot end 411, the third hot end, the first external circulation fan 51 and the second external circulation fan 52, making the airflow of the external circulation smoother and more stable, and the heat dissipation effect better. Among them, the air inlet directions of the first external circulation fan 51 and the second external circulation fan 52 in this embodiment are opposite, so that external air can enter from more directions, improving the flow efficiency of the external flow field.

[0064] In this embodiment, the first radiator 41 and the second radiator 42 can be radiators such as aluminum extrusion radiators, copper-aluminum welded radiators or die-cast radiators, in which the hot end and the cold end are integrally connected. The LED radiator 64 is a heat pipe radiator, and the third hot end and the third cold end are separated from each other and connected by a heat conduction pipe.

[0065] As Figure 8 shown, this embodiment also provides an LCD projector, which includes: a projection housing 81 and the enclosed optical engine of this embodiment arranged in the projection housing 81. There are heat dissipation holes provided at multiple places on the projection housing. The projector applying the enclosed optical engine of the embodiment of the present invention is beneficial to miniaturization design, has good heat dissipation effect and high sealing performance.

[0066] The above embodiments only represent several implementation manners of the present invention. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the invention. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several deformations and improvements can still be made, and these all belong to the protection scope of the present invention.

Claims

1. A closed optical machine using helium for heat dissipation and temperature control, characterized in that: include: Optical machine housing, internal circulation fan unit, heat dissipation module and control components; A first accommodating chamber and a second accommodating chamber spaced apart from each other are formed in the optical machine housing, the first accommodating chamber is connected to the second accommodating chamber through a first vent and a second vent, the first accommodating chamber and the second accommodating chamber are filled with helium, and a partition and an imaging module are arranged in the first accommodating chamber; The imaging module comprises a first lens, an LCD screen, a second lens and a reflector which are sequentially arranged along a light propagation path; the partition, the LCD screen, the second lens and the reflector jointly divide the first accommodation cavity into a first heat dissipation duct, a second heat dissipation duct, a first air passage cavity and a second air passage cavity; the first heat dissipation duct and the second heat dissipation duct are respectively located on opposite sides of the LCD screen; the right ends of the first heat dissipation duct and the second heat dissipation duct are both connected to the first air passage cavity; the left ends of the first heat dissipation duct and the second heat dissipation duct are both connected to the second air passage cavity; the first vent is arranged corresponding to the position of the first heat dissipation duct; a part of the second vent is connected to the first air passage cavity; and another part of the second vent is connected to the second air passage cavity; The internal circulation fan unit includes a first internal circulation fan and a second internal circulation fan, wherein the first internal circulation fan is arranged in the second accommodating chamber and is used to output gas toward the first vent, and the second internal circulation fan is arranged in the second air passage chamber and is used to output gas toward the second heat dissipation air duct, and the first internal circulation fan and the second internal circulation fan are both equipped with a rotation speed sensor; The heat dissipation module includes a first heat sink and a second heat sink, the first heat sink includes a first cold end and a first hot end connected to conduct heat, the second heat sink includes a second cold end and a second hot end connected to conduct heat, the first cold end is arranged in the second accommodating cavity, the second cold end is arranged in the second air passage cavity, and the first hot end and the second hot end are both facing the outside of the optical machine housing; The control component includes a main control board and a first temperature sensor, a second temperature sensor, and a helium concentration detector electrically connected to the main control board. The main control board is also electrically connected to the first internal circulation fan and the second internal circulation fan. The first temperature sensor is used to detect first temperature data of the first heat dissipation air duct, the second temperature sensor is used to detect second temperature data of the second heat dissipation air duct, the helium concentration detector is used to detect current helium concentration data in the first accommodating chamber, and the main control board is used to adjust the rotation speed of the first internal circulation fan and the second internal circulation fan according to the first temperature data, the second temperature data and the current helium concentration.

2. The enclosed optical machine using helium gas for heat dissipation and temperature control according to claim 1, characterized in that: The adjustment method of the main control board includes: Assume that the initial rotation speeds of the first internal circulation fan and the second internal circulation fan are N1, the initial helium concentration data of the first accommodating chamber is P1, the heat dissipation rate at the initial rotation speed N1 and the initial helium concentration data P1 is A1, and the safety temperature threshold is T1; Obtain the current helium concentration data P2, and output the heat dissipation rate A2 under the initial rotation speed N1 and the current helium concentration data P2, where A2=(P2 / P1)×A1; Obtain the first temperature data T2. If T2 is greater than T1, adjust the speed of the first internal circulation fan to N2, where N2 = ((A1-A2) / A1+1)×N1+((T2-T1) / T1)×N1; The second temperature data T3 is obtained. If T3 is greater than T1, the rotation speed of the second internal circulation fan is adjusted to N3, where N3 = ((A1-A2) / A1+1)×N1+((T3-T1) / T1)×N1.

3. The enclosed optical machine using helium gas for heat dissipation and temperature control according to claim 1 or 2, characterized in that: The optical machine housing includes a top shell, a middle shell and a bottom shell connected in sequence from top to bottom, the top shell and the middle shell together enclose the first accommodating cavity, the bottom shell and the bottom of the middle shell together enclose the second accommodating cavity, and the bottom of the middle shell is provided with the first vent and the second vent.

4. The enclosed optical machine using helium gas for heat dissipation and temperature control according to claim 3, characterized in that: A sealing groove is arranged around the top edge of the middle shell, a sealing ring is arranged in the sealing groove, and the top shell cooperates with the middle shell to press the sealing ring tightly.

5. The enclosed optical machine using helium gas for heat dissipation and temperature control according to claim 4, characterized in that: A heat dissipation installation opening is provided on a side wall of the middle shell corresponding to the second air passage cavity, the second radiator is installed in the heat dissipation installation opening, and the second cold end faces the second air passage cavity.

6. The enclosed optical machine using helium gas for heat dissipation and temperature control according to claim 1, characterized in that: A guide plate is disposed between the right end of the first heat dissipation duct and the right end of the second heat dissipation duct, and the guide plate is used to separate the air exhausted from the first heat dissipation duct and the second heat dissipation duct.

7. The sealed optical machine using helium gas for heat dissipation and temperature control according to claim 3, characterized in that: It also includes a light source module, which includes an LED light source, a light funnel and a light funnel shell. An opening is opened on the middle shell corresponding to the side wall of the LCD screen. The light funnel shell is installed at the opening. The light funnel is arranged in the light funnel shell. The light outlet of the light funnel faces the LCD screen, and the light inlet of the light funnel is arranged at the LED light source.

8. The sealed optical machine using helium gas for heat dissipation and temperature control according to claim 7, characterized in that: It also includes an LED heat sink, which includes a third cold end and a third hot end connected to conduct heat, and the third cold end is in contact with the LED light source.

9. The sealed optical machine using helium gas for heat dissipation and temperature control according to claim 8, characterized in that: It also includes an external circulation fan unit, which includes a first external circulation fan and a second external circulation fan with the same air outlet direction, and the first hot end and the third hot end are both arranged at the air outlets of the first external circulation fan and the second external circulation fan.

10. An LCD projector, characterized in that: include: A projection housing and a sealed optical machine as described in any one of claims 1 to 9 disposed in the projection housing.

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