A zero-noise projector

Abstract

The present invention discloses a zero-noise projector, comprising a projector housing, and an optical system, an illumination segment light housing, an imaging segment light housing, a first radiator, a second radiator, a light source heat transfer device, an air guide bowl housing, an air guide pipe housing, a structural support, a fan and a heat insulation tube located within the projector housing. The optical system comprises an LED light source, a condenser, a collimating lens, an LCD light valve module, a field lens, a reflector and a projection lens arranged in sequence according to the direction of light travel. The LCD light valve module comprises an APF film, a transparent heat conducting plate, an LCD light valve and an output polarizer arranged in sequence according to the direction of light travel. The present invention innovatively achieves the technical indicator of being "silent" to the consumer's hearing, which undoubtedly improves the satisfaction of various originally picky users when experiencing the products of the present invention, creates more economic value for the market, and reduces the costs of various links such as production, sales, logistics, and returns.

Description

Technical Field

[0001] The present invention relates to the technical field of projectors, and in particular to a zero-noise projector. Background Art

[0002] While domestic projectors have achieved remarkable results in reducing noise levels in recent years, some consumers still have high expectations for noise levels that far exceed all the industry's technological advancements. This is most evident in the fact that operating noise remains a key reason for returns after online purchases (e.g., on JD.com, Taobao, Douyin, Amazon, and AliExpress). Therefore, reducing projector noise is a technical challenge that requires continuous and innovative solutions.

[0003] There's no such thing as a completely noiseless or zero-noise projector, as absolute zero noise requires at least no sound source. Projectors equipped with components like high-frequency switching power supplies and forced cooling fans inherently produce noise. Projector noise isn't simply a technical issue; it's influenced by a host of subjective and objective factors, including the consumer's psychology, physiology, and spatial environment. This can lead to returns for projectors with excellent noise performance.

[0004] We can use "ambient noise" as a reference to evaluate the impact of a projector's noise on the human ear and determine the threshold for consumer dissatisfaction with the product. If the sound pressure level (SPL) or loudness of a product's operating noise is lower than the ambient noise level, objectively speaking, the product's noise performance is excellent. However, urban and rural ambient noise levels are quite different. If the SPL is significantly lower than typical living noise levels, or comparable to the noise threshold that affects sleep quality, the product's noise level is virtually negligible. However, these relative noise indicators are far from sufficient. Consumers' expectations of product quality, such as those influenced by psychological and physiological factors, must also be considered. Perhaps only when the noise level approaches the hearing threshold of a normal adult—meaning that consumers cannot detect the noise when they put their ear to the projector casing—will consumers generally rate the product's noise as "satisfactory" or "zero noise." This noise level can be considered "noiseless" or "zero noise."

[0005] The purpose of the present invention is to make the noise index of the projector reach the extreme level of "zero noise" mentioned above to increase consumers' satisfaction with the product. Summary of the Invention

[0006] The purpose of the present invention is to overcome the shortcomings of the existing technology and provide a zero-noise projector. The present invention innovatively achieves the technical indicator of making the consumer's hearing "silent", which undoubtedly improves the satisfaction of various originally picky users when experiencing the products of the present invention, creates more economic value for the market, and reduces the costs of various links such as production, sales, logistics, and returns.

[0007] To achieve the above-mentioned objectives, the present invention provides a zero-noise projector, including a projector housing, and an optical system, an illumination segment light housing, an imaging segment light housing, a first radiator, a second radiator, a light source heat transfer device, an air guide bowl housing, an air guide pipe housing, a structural support, a fan and an insulation tube located within the projector housing.

[0008] The optical system comprises an LED light source, a condenser, a collimating lens, an LCD light valve module, a field mirror, a reflecting mirror and a projection lens, which are arranged in sequence according to the direction of light travel.

[0009] The LCD light valve module includes an APF film, a transparent heat conducting plate, an LCD light valve and an output polarizer which are sequentially laminated and arranged according to the direction of light travel.

[0010] The length and width of the transparent heat conducting plate are a*b, the length and width of the LCD light valve are a'*b', a-a'≥3mm, b-b'≥3mm.

[0011] The structural support is made of metal; the structural support is provided with a plane for fitting and mounting the transparent heat conducting plate, a hollow square hole is provided in the center of the plane, the LCD light valve and the output polarizer are located in the square hole; the transparent heat conducting plate is fitted on the plane of the structural support.

[0012] The incident end of the lighting segment light housing is provided with a light source mounting port, and the LED light source is installed at the light source mounting port; the condenser and the collimating lens are installed inside the lighting segment light housing; the exit end of the lighting segment light housing is connected to the incident end of the structural support.

[0013] The exit end of the imaging segment light housing is provided with a lens mounting port, and the projection lens is mounted at the lens mounting port; the field lens and the reflector are mounted inside the imaging segment light housing; the incident end of the imaging segment light housing is connected to the exit end of the structural support.

[0014] The optical system, the lighting section optical machine housing, the structural support and the imaging section optical machine housing are combined into a closed optical machine.

[0015] The second radiator is a tubular profile radiator, the inner wall of the second radiator is in contact with the outer wall of the structural support, a plurality of second heat expansion ribs are provided on the outer wall of the second radiator, and a second notch is provided on the second radiator for avoiding the projection lens and the imaging segment light housing.

[0016] The first radiator is a tubular profile radiator, and a plurality of first heat expansion ribs are provided on the inner wall and / or outer wall of the first radiator. The first radiator is provided with a first notch for avoiding the projection lens and the imaging section optical housing.

[0017] The second radiator is placed inside the first radiator; and the heat insulation tube is arranged between the second radiator and the first radiator.

[0018] The length of the heat-insulating tube is less than or equal to the length of the second radiator, and the heat-insulating tube is provided with a third notch for avoiding the projection lens and the imaging segment optical housing.

[0019] The back of the LED light source is attached to the middle part of the light source heat transfer device; the air guide bowl shell is a curved bowl-shaped structure, and the air guide bowl shell covers the LED light source, the middle part of the light source heat transfer device and the incident end of the lighting section light machine housing, and the open end of the air guide bowl shell matches the size of the rib base of the second radiator and is connected; the air guide bowl shell is provided with a hole or notch for avoiding the light source heat transfer device, and the two ends of the light source heat transfer device are connected to the rib base of the first radiator after passing through the hole or notch on the air guide bowl shell.

[0020] The fan is installed at the bottom inside the projector housing and is located below the air guide bowl shell. The closed end of the air guide bowl shell matches and is opposite to the outer diameter of the fan motor and is less than 5mm away from the fan. The fan adopts an axial flow fan.

[0021] The air duct shell has a curved cylindrical structure; the air inlet end of the air duct shell matches and is connected to the air outlet size of the fan, the air outlet end matches and is connected to the inner wall size of the projector housing, and the position of the air outlet end is higher than the air inlet end; a drainage air duct is formed between the outer wall of the air guide bowl shell and the inner wall of the air duct shell.

[0022] A first natural convection air duct is formed between the rib base of the second radiator and the inner wall of the insulation tube; a second natural convection air duct is formed between the outer wall of the insulation tube and the rib base of the first radiator; and a third natural convection air duct is formed between the rib base of the first radiator and the inner wall of the projector housing.

[0023] A plurality of air inlet holes are provided at the bottom of the projector housing; the air inlet of the fan is opposite to the air inlet holes; a plurality of air outlet holes are provided at the top of the projector housing; external cold air flows in through the plurality of air inlet holes, passes through the fan, passes through the drainage air duct, and passes through the first natural convection air duct, the second natural convection air duct and the third natural convection air duct, and then the cold air is heated and discharged into the atmosphere from the plurality of air outlet holes.

[0024] Furthermore, the transparent heat conducting plate is any one of sapphire glass, transparent optical crystal or glass-based single-layer graphene heat conducting plate.

[0025] Furthermore, a plurality of acceleration holes are provided in the upper middle portion of the heat-insulating tube; the plurality of acceleration holes are waist-shaped structures, and the acceleration holes are inclined upward from the inner wall of the heat-insulating tube to the outer wall thereof.

[0026] Furthermore, when the ambient temperature is lower than 35° C., assuming that the number of blades of the fan is a, the rotation speed of the fan is less than 1200 / a, where the unit of the rotation speed is revolutions per minute.

[0027] Furthermore, the cross-section of the outer wall of the structural support is a rectangular structure, and correspondingly, the cross-section of the inner wall of the second radiator is a rectangular structure.

[0028] Alternatively, the cross section of the outer wall of the structural support is a four-segment circular arc structure, and correspondingly, the cross section of the inner wall of the second radiator is a four-segment circular arc structure.

[0029] Furthermore, the light source heat transfer device adopts a heat pipe or a phase change suppression plate.

[0030] The beneficial effects of the present invention are as follows:

[0031] 1. The heat generated by the APF film, LCD light valve, and output polarizer during operation is rapidly transferred to the transparent heat-conducting plate. The heat is then rapidly transferred to the metal structural support via the transparent heat-conducting plate. The heat is then rapidly transferred to the second heat sink via the structural support with extremely low thermal resistance. The heat is then diffused into the atmosphere via the second heat-expanding fins of the second heat sink, dissipating heat from the LCD light valve. This eliminates the need for a powerful fan to cool the LCD light valve surface, thus eliminating noise. Heat from the LED light source is then transferred to the first heat sink via the light source heat transfer device. The heat is then diffused into the atmosphere via the first heat-expanding fins of the first heat sink, dissipating heat from the LED light source. Regarding the drainage duct, the first natural convection duct, the second natural convection duct, and the third natural convection duct, in practice, the height of the projector is generally above 190mm-220mm, providing a certain chimney effect and generating strong natural convection. The product of the present invention innovatively achieves the technical indicator of making the product "silent" to consumers' hearing, which undoubtedly improves the satisfaction of various originally picky users when experiencing the product of the present invention, and further reduces the possibility of consumers returning the product due to psychological and physiological annoyance with noise, creating more economic value for the market and reducing costs in various links such as production, sales, logistics, and returns.

[0032] 2. The existing technology uses a powerful fan inside the projector to force air cooling on the LED light source. Cold air enters through the air inlet on the housing and is discharged through the air outlet. As a result, dust gradually accumulates on the housing's air inlet, the fan impeller on the internal air duct, and the heat sink's thermal expansion fins after the projector has been running for a period of time (generally much less than 500-1000 hours, depending on the air parameters of the operating environment), causing blockage and significantly reducing the projector's heat dissipation performance. In severe cases, the housing's air inlet can become blocked, and excessive dust accumulates on the fan impeller and heat sink's thermal expansion fins, leading to failure. This is common in the industry. The present invention, however, uses natural convection, and dust accumulation is primarily the natural deposition of dust in the air. There is no risk of blockage of the air inlet or thermal expansion fins during extended operation. Furthermore, the fan of the present invention rotates at an extremely low speed, below the speed at which it produces sound, preventing dust accumulation on the fan blades and causing failure. This significantly improves the product's usability and provides users with a worry-free product.

[0033] 3. The heat-insulating tube of the present invention is provided with a plurality of accelerating holes, which produce a stronger chimney effect and improve the convection effect in the first natural convection air duct and the second natural convection air duct, thereby improving the heat dissipation efficiency of the LED light source and the LCD light valve. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0035] Figure 1 A perspective view of the present invention;

[0036] Figure 2 for Figure 1 Schematic cross-section diagram;

[0037] Figure 3 is a schematic diagram of the optical system of the present invention;

[0038] Figure 4 is a schematic diagram of the structural support of the present invention;

[0039] Figure 5 Schematic cross-section of the LCD light valve module and the structural support of the present invention;

[0040] Figure 6 for Figure 5 Further illustration of ;

[0041] Figure 7 This is a diagram showing the appearance of the optical machine of the present invention;

[0042] Figure 8 This is a diagram showing the optical engine and the second heat sink of the present invention;

[0043] Figure 9 for Figure 8 Partial cutaway view;

[0044] Figure 10 It is a partial cross-sectional view of the heat-insulating cylinder of the present invention;

[0045] Figure 11 This is a diagram showing the first heat sink, LED light source, and light source heat transfer device of the present invention;

[0046] Figure 12 A diagram showing the optical engine, the first heat sink, the second heat sink, and the heat insulation cylinder of the present invention;

[0047] Figure 13 This is a diagram showing the second radiator, air guide bowl and fan of the present invention;

[0048] Figure 14 This is a diagram showing the fan, air guide bowl shell and air guide pipe shell of the present invention;

[0049] Figure 15 for Figure 1A partial cutaway view of the projector with the outer casing removed.

[0050] Explanation of the above figures:

[0051] 1. Projector housing, 2. Illumination section housing, 3. Imaging section housing, 4. First radiator, 5. Second radiator, 6. Light source heat transfer device, 7. Air guide bowl housing, 8. Air guide tube housing, 9. Structural bracket, 10. Fan, 12. Thermal insulation tube, 91. Plane, 111. LED light source, 112. Condenser, 113. Collimating lens, 114. LCD light valve module, 115. Field lens, 116. Reflector, 117. Projection lens, 121. Acceleration hole, 122. Third notch, 130. Drainage duct, 131. First natural convection duct, 132. Second natural convection duct, 133. Third natural convection duct, 1041. APF film, 1042. Transparent heat conduction plate, 1043. LCD light valve, 1044. Output polarizer. DETAILED DESCRIPTION

[0052] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is described in detail below with reference to the accompanying drawings. The description in this part is only exemplary and explanatory and should not have any limiting effect on the scope of protection of the present invention.

[0053] Since "zero noise" projectors have never been available on the market in decades, it is necessary to further explain the innovative measures of the present invention in combination with the current state of industry technology.

[0054] Obviously, if we ignore the noise generated by the electromagnetic field oscillations of the projector's high-frequency switching power supply during operation (which is inaudible to the human ear if the quality is acceptable), then the pursuit of a "zero-noise" projector design only relies on the single issue of heat dissipation. In other words, as long as there is no fan or the fan is running at a speed below the human hearing threshold, the projector will not be "noisy" at all.

[0055] When the projector is not equipped with a fan, the entire projector's cooling system operates by natural convection. The projector's light source (e.g., LED light source 111) is the primary source of heat within the projector. For heat generated by circuits such as the switching power supply's MOS transistors, Schottky diodes, and switching transformer, as well as the projector's main control chip, minimal heat dissipation technology (e.g., attaching a heat sink to the chip) can maintain stable operation of these components. Therefore, the focus is on natural convection cooling of both the primary heat provided by the LED light source 111 and the derived heat generated by this primary heat, such as heat from the LCD light valve 1043.

[0056] See also Figure 3After the LED light source 111 consumes electrical power E, a portion of E (E = E1 + E2) is directly converted into thermal power E1 (Joule heat). The remaining portion generates optical power E2 (E2 = E21 + E22) and enters the projector's optical system. Some optical power E21 is lost between the LED light source 111 and the LCD light valve module 114. This power is ultimately dissipated as heat, such as stray light hitting the inner wall of the illumination section housing 2. Furthermore, some light absorbed by the condenser 112 and collimating lens 113 is converted into Joule heat. The remaining optical power E22 evenly illuminates the LCD light valve module 114. Approximately 5%*E22 of the light (set as E3) passes through the LCD light valve module 114 (currently in full-color display mode), and ultimately approximately 90%*E3 of the light (set as E4) is emitted from the projection lens 117 to form an image. Approximately 10%*E3 of the light is consumed by heat (set as E5) along the optical path after the LCD light valve module 114. The light absorbed by the LCD light valve module 114 is approximately 95%*E22 (set as E6). In summary, E22 = E3 + E6, and E3 = E4 + E5. With E4 being the power visible to the user, the remaining E1, E21, E5, and E6 represent thermal power.

[0057] The LED light source 111 is typically designed based on thermal power E1, and the heat dissipation of the LCD light valve module 114 is typically designed based on optical power E6. However, sufficient safety margins should be left based on experience. The remaining thermal powers, such as E21 and E5, can be designed through appropriate structures and material selection to ensure that the corresponding raw materials reach thermal equilibrium and remain within a safe temperature range.

[0058] See also Figure 1-15 As shown, a zero-noise projector provided in this embodiment includes a projector housing 1, and an optical system, an illumination segment light housing 2, an imaging segment light housing 3, a first radiator 4, a second radiator 5, a light source heat transfer device 6, an air guide bowl housing 7, an air guide pipe housing 8, a structural bracket 9, a fan 10 and an insulation tube 12 located in the projector housing 1.

[0059] See also Figure 3 As shown, the optical system includes an LED light source 111, a condenser 112, a collimating lens 113, an LCD light valve module 114, a field lens 115, a reflector 116, and a projection lens 117, which are arranged in sequence according to the direction of light travel. In this embodiment, the condenser 112 is preferably, but not limited to, a square-conical condenser; the collimating lens 113 is preferably, but not limited to, a glass lens, but can be a plastic Fresnel lens; and the field lens 115 is preferably, a Fresnel lens. Similar optical systems are also the optical structures adopted by the vast majority of single-LCD projectors in the industry today, and will not be described in detail here.

[0060] See also Figure 4-Figure 6 As shown, the LCD light valve module 114 includes an APF film 1041 , a transparent heat conducting plate 1042 , an LCD light valve 1043 and an output polarizer 1044 , which are sequentially attached and arranged in the direction of light travel.

[0061] Assuming that the length and width of the transparent heat conductive plate 1042 are a*b, and the length and width of the LCD light valve 1043 are a'*b', then a-a'≥3mm, b-b'≥3mm; in this embodiment, preferably but not limited to a-a'=5mm, b-b'=6mm.

[0062] The material of the structural support 9 is metal (such as aluminum alloy 6063, copper and other high thermal conductivity materials, not limited to this), and the structural support 9 is provided with a plane 91 for fitting and mounting the transparent thermal conductive plate 1042. A hollow square hole is provided in the center of the plane 91, and the LCD light valve 1043 and the output polarizer 1044 are located in the square hole; the transparent thermal conductive plate 1042 is fitted on the plane 91 of the structural support 9.

[0063] Figure 4 The arrow in the figure indicates that the transparent heat-conducting plate 1042 is attached to the flat surface 91 of the structural support 9 in the direction of the arrow. For the specific attachment, a curable silicone-based thermally conductive adhesive is preferably used, but not limited to. The silicone-based thermally conductive adhesive often squeezes into the gap between the LCD light valve 1043 and the inner wall of the square hole, thereby enhancing heat conduction and blocking stray light. Figure 6 The arrows in FIG. 1 indicate the direction of light traveling in the LCD light valve module.

[0064] The APF (Advanced Polarizer Film) film 1041 is a new process material that has become popular in the industry in recent years. Specifically, it is used by polarizer suppliers to integrate reflective polarizers and absorptive polarizers into one to improve the production efficiency of the LCD panel industry when laminating polarizers.

[0065] See also Figure 2 、 Figure 7 、 Figure 9 As shown, the incident end of the lighting segment light housing 2 is provided with a light source mounting port, and the LED light source 111 is installed at the light source mounting port; the condenser 112 and the collimating lens 113 are installed inside the lighting segment light housing 2; the exit end of the lighting segment light housing 2 is connected to the incident end of the structural bracket 9.

[0066] The exit end of the imaging segment light housing 3 is provided with a lens mounting port, to which the projection lens 117 is mounted. The field lens 115 and the reflector 116 are mounted within the imaging segment light housing 3. The incident end of the imaging segment light housing 3 is connected to the exit end of the structural support 9. The LED light source 111, the illumination segment light housing 2, the structural support 9, the imaging segment light housing 3, and the projection lens 117 are typically connected via screws, which is common knowledge in projector construction and is not shown in the figure.

[0067] The optical system, the lighting section optical housing 2, the structural support 9 and the imaging section optical housing 3 are combined into a closed optical machine. Figure 7 shown.

[0068] See also Figure 8 、 Figure 9 As shown, the second radiator 5 is a tubular profile radiator, the inner wall of the second radiator 5 is in contact with the outer wall of the structural support 9, a plurality of second heat expansion ribs are provided on the outer wall of the second radiator 5, and the second radiator 5 is provided with a second notch for avoiding the projection lens 117 and the imaging segment light housing 3 (the portion corresponding to the exit end of the imaging segment light housing 3).

[0069] See also Figure 2 、 Figure 11 、 Figure 12 、 Figure 15 As shown in FIG. 1 , the first heat sink 4 is a tubular heat sink with a plurality of first heat-expanding fins provided on its inner and / or outer walls. The first heat sink 4 also includes a first notch to accommodate the projection lens 117 and the imaging section optical housing 3. In this embodiment, since heat dissipation performance is sufficient simply by providing the first heat-expanding fins on the inner wall of the first heat sink 4, no heat-expanding fins are provided on the outer wall of the first heat sink 4, effectively reducing the size of the projector. The second heat sink 5 is positioned within the first heat sink 4, with the thermal insulation tube 12 positioned between the second heat sink 5 and the first heat sink 4.

[0070] The purpose of providing the insulating tube 12 is to prevent mutual radiation and convection crosstalk between the first and second radiators 4, 5. As air convection rises, the first and second radiators 4, 5 are designed to have a significant temperature difference and temperature gradient at each corresponding height. The insulating tube 12 effectively prevents mutual radiation and convection crosstalk, significantly improving the efficiency of natural convection heat transfer while allowing the first and second radiators 4, 5 to operate according to their designed operating conditions.

[0071] See also Figure 10As shown, the length of the insulation tube 12 is less than or equal to the length of the second heat sink 5. This length difference has a correlated impact on the wind resistance at the air inlets of the first natural convection air duct 131 and the second natural convection air duct 132. The insulation tube 12 is provided with a third notch 122 for accommodating the projection lens 117 and the imaging segment light housing 3.

[0072] See also Figure 11-14 As shown, the back of the LED light source 111 is attached to the middle part of the light source heat transfer device 6 (if the light source heat transfer device 6 uses a heat pipe, the current popular practice is to make a metal substrate 61 that matches the size of the LED light source 111 in the middle part to install the LED light source 111, and the back of the metal substrate 61 is connected to the heat pipe. This is common knowledge in the industry and will not be repeated. There is also a practice of directly attaching the back of the LED light source to the heat pipe, such as the Samsung SP-F10M projector launched in 2010). In this embodiment, the light source heat transfer device 6 preferably uses a heat pipe for heat transfer, and the inner wall of the first radiator 4 is provided with a plurality of sheep horn grooves 41 for wrapping (or inlaying) the heat pipe to facilitate sufficient heat conduction; the air guide bowl shell 7 is a curved bowl-shaped structure, and the air guide bowl shell 7 covers the LED light source 111, the middle part of the light source heat transfer device 6 (such as the metal substrate 61) and the lighting section light machine housing 2 The incident end of the air guide bowl shell 7 is matched with the size of the rib base of the second radiator 5 and is connected (to facilitate the formation of the drainage air duct 130); the air guide bowl shell 7 is provided with a hole or notch for avoiding the light source heat transfer device 6 (such as for avoiding the heat pipe), and the two ends of the light source heat transfer device 6 (such as the heat pipe) pass through the holes or notches on the air guide bowl shell 7 and are connected to the rib base of the first radiator 4 (firmly embedded in multiple horn grooves 41).

[0073] The fan 10 is installed at the bottom inside the projector housing 1 and is located below the air guide bowl shell 7. The closed end of the air guide bowl shell 7 matches and is opposite to the outer diameter of the fan 10 motor and is less than 5 mm away from the fan 10. The fan 10 adopts an axial flow fan. Figure 13 In the figure, the fan 10 is farther away from the air guide bowl 7 to facilitate observation and understanding of the specific structure there.

[0074] The air duct shell 8 is a curved cylindrical structure; the air inlet end of the air duct shell 8 matches the size of the air outlet of the fan 10 and is connected, and the air outlet end matches the size of the inner wall of the projector housing 1 and is connected (to facilitate the formation of a drainage air duct 130), and the position of the air outlet end is higher than the air inlet end to facilitate the upward direction of natural convection and optimize wind resistance. The drainage air duct 130 is formed between the outer wall of the air guide bowl shell 7 and the inner wall of the air duct shell 8 (see Figure 2).

[0075] Continue to see Figure 2 As shown by the dotted lines and arrows in the figure, a first natural convection duct 131 is formed between the rib base of the second radiator 5 and the inner wall of the insulation tube 12; a second natural convection duct 132 is formed between the outer wall of the insulation tube 12 and the rib base of the first radiator 4; and a third natural convection duct 133 is formed between the rib base of the first radiator 4 and the inner wall of the projector housing 1.

[0076] The bottom of the projector housing 1 is provided with a plurality of air inlet holes; the air inlet of the fan 10 is opposite to the air inlet holes; the top of the projector housing 1 is provided with a plurality of air outlet holes; the external cold air flows in through the plurality of the air inlet holes, passes through the fan 10, passes through the drainage duct 130, and passes through the first natural convection duct 131, the second natural convection duct 132 and the third natural convection duct 133 (arranged in parallel), and then the cold air is heated and discharged into the atmosphere from the plurality of the air outlet holes.

[0077] In this embodiment, the heat generated by the APF film 1041, LCD light valve 1043, and output polarizer 1044 during operation is rapidly transferred to the transparent heat-conducting plate 1042. The heat is then rapidly transferred to the metal structural support 9 via the transparent heat-conducting plate 1042. The heat is then rapidly transferred to the second heat sink 5 via the structural support 9 with extremely low thermal resistance. The heat is then diffused into the atmosphere via the second heat-expanding fins of the second heat sink 5, thus dissipating heat from the LCD light valve 1043. This eliminates the need for a powerful fan to cool the surface of the LCD light valve 1043, and eliminates noise. In this embodiment, the transparent heat-conducting plate 1042 is preferably, but not limited to, made of sapphire glass with a thickness of 0.7-1 mm. When the thermal power E6 of the LCD light valve module (e.g., LCD light valve 1043 is a 3.5-inch module manufactured by BOE) is approximately 6.84 W-6.9 W, the temperature difference between the central portion of the LCD light valve 1043 and the structural support 9 is less than 24°C, and the temperature difference between the structural support 9 and the environment is less than 15°C, thereby ensuring that the LCD light valve 1043 operates within a safe temperature range (less than 75°C). Heat from the LED light source 111 is transferred to the first heat sink 4 via the light source heat transfer device 6 and diffused into the atmosphere via a plurality of first heat diffusion fins on the first heat sink 4, thereby dissipating heat from the LED light source 111. The drainage duct 130, the first natural convection duct 131, the second natural convection duct 132, and the third natural convection duct 133 are generally shaped like a "vertical shaft." The projector of the present invention has a height of 190 mm to 220 mm or greater (corresponding to a 3.5-inch to 4-inch LCD light valve 1043), exhibiting a certain chimney effect and capable of generating strong natural convection (for quantitative analysis of parameters such as the thermal pressure difference of the chimney effect, reference can be made to the American ASHRAE Handbook and related basic physics knowledge, which is well known). Inside a sealed optical engine, the existing technology is to blow air on the surface of the LCD light valve through forced air cooling, and then use a heat exchanger to transfer the heat of the air inside the optical engine to the outside of the optical engine and diffuse it into the atmosphere (see several patent technologies such as Chinese Patent Publication No. CN217386118U). The total heat transfer coefficient or thermal resistance between the LCD light valve and the atmosphere is composed of four parts: the thermal resistance R1' between the LCD light valve and the internal air, the thermal resistance R2' between the internal air and the heat absorption part of the heat exchanger, the thermal resistance R3' between the heat absorption part and the heat release part of the heat exchanger, and the thermal resistance R4' between the heat release part and the atmosphere.Obviously, the total heat transfer coefficient or thermal resistance between the LCD light valve module 114 (heat output E6) of the present invention and the atmosphere is composed of three components: thermal resistance R1 between the LCD light valve module 114 and the structural support 9, thermal resistance R3 between the structural support 9 and the second heat sink 5, and thermal resistance R4 between the second heat sink 5 and the atmosphere. Through simple design, thermal resistance R1 can undoubtedly be made ≤ R1' (because the thermal conductivity of the transparent heat conductive plate 1042 is much greater than the heat transfer coefficient for forced air cooling of the LCD light valve). The thermal resistance corresponding to R2' does not exist in the present invention. R3 is reliable conduction between metals and has sufficient cross-sectional area, so R3 can be ignored. R4 (the area of ​​the plurality of second heat expansion fins, natural convection heat transfer coefficient, etc.) is relatively critical. As long as R4 ≤ R2' + R3' + R4' is ensured, the LCD light valve module 114 of the present invention can operate in a safer temperature environment compared to the prior art.

[0078] The product of this embodiment innovatively achieves the technical indicator of making the product "silent" to consumers' ears, which undoubtedly improves the satisfaction of various originally picky users when experiencing the product of the present invention, and further reduces the possibility of consumers returning the product due to psychological and physiological annoyance with noise, creating more economic value for the market and reducing costs in various links such as production, sales, logistics, and returns.

[0079] Existing technology uses a powerful fan inside the projector to force air cooling on the LED light source. Cool air enters through the air inlet on the housing and exits through the air outlet. Consequently, dust accumulates on the housing's air inlet, the fan impeller on the internal air duct, and the heat sink's thermal fins after the projector has been running for a while, leading to blockage and significantly reducing the projector's heat dissipation performance. In severe cases, the housing's air inlet can become blocked, and excessive dust accumulates on the fan impeller and heat sink's thermal fins, causing them to fail. This is a common occurrence in the industry. This embodiment, however, utilizes natural convection, where dust accumulation primarily occurs through the natural deposition of airborne dust. There is no risk of blockage of the air inlet or thermal fins. Furthermore, the fan 10 in this embodiment rotates only at an extremely low speed, below the speed at which it produces sound. This prevents dust from accumulating on the fan blades and causing them to fail. This significantly improves the product's usability and provides users with a worry-free product.

[0080] In the present embodiment, the transparent heat conducting plate 1042 is any one of sapphire glass, transparent optical crystal or glass-based single-layer graphene heat conducting plate. It should be noted that, strictly speaking, sapphire (crystallized aluminum oxide) is also a kind of crystal, but because traditionally transparent optical crystal refers to materials such as optical grade quartz crystal, it is listed separately. In addition, the glass-based single-layer graphene heat conducting plate refers to a single-layer graphene grown on a glass substrate (currently needs to be imported from Europe and the United States), which has excellent thermal conductivity. The relevant technologies of sapphire glass and graphene are relatively advanced and efficient in the industry, and have gradually been commercialized. Specifically, reference can be made to leading innovative technologies such as Chinese Patent Publication No. CN211236549U and CN213545027U.

[0081] In this embodiment, the light source heat transfer device 6 is a heat pipe or a phase change inhibitor plate. For the innovative application of phase change inhibited (PCI) heat transfer technology in projectors, please refer to Chinese Patent Application No. 202211106386.5, which will not be repeated here.

[0082] See also Figure 10 As shown, in this embodiment, a plurality of acceleration holes 121 are provided in the middle and upper part of the heat-insulating tube 12 (the specific part is in the vertical direction, which refers to the part above the middle part of the heat-insulating tube 12); the plurality of acceleration holes 121 are waist-shaped structures, and the acceleration holes 121 are inclined upward from the inner wall of the heat-insulating tube 12 to its outer wall (see Figure 10 (shown in cross-section). In the upper-middle portion, the air temperature inside the insulation tube 12 (the first natural convection duct 131) is lower than the air temperature outside (the second natural convection duct 132). When cold air A1 flows into the insulation tube 12, it rises due to natural convection. After a number of acceleration holes 121 are provided in the upper-middle portion of the insulation tube 12, A1 can pass through the insulation tube 12 from the inside out (see A2), further cooling the first radiator 4 in the second natural convection duct 132.

[0083] The acceleration hole 121 is inclined upward, and the pressure at the upper end (inside the second natural convection duct 132, the air temperature is higher and the air flow rate is faster) is less than the pressure at the lower end (inside the first natural convection duct 131, the temperature is lower and the speed is slower), so the air inside the insulation tube 12 will pass through the acceleration hole 121 and flow upward to the outside, thereby lowering the temperature of the air inside the second natural convection duct 132, increasing the temperature difference between the first radiator 4 and the air, and thereby improving the heat dissipation efficiency of the first radiator 4; at the same time, increasing the flow rate at the entrance of the first natural convection duct 131, thereby improving the heat dissipation efficiency of the second radiator 5.

[0084] The ambient temperature in most usage scenarios is below 35°C (this temperature is the standard of the China Projection Industry Association). In this embodiment, assuming the number of blades (number of blades) of the fan 10 is a, and the speed of the fan 10 is ≤1200 / a (unit: revolutions per minute), the air-breaking and impact force (generated by the angle of attack) generated between the blades and the air during operation of the fan 10 is insufficient to produce a fundamental wave >20Hz (the fundamental wave carries the main energy of low-frequency sound). Extensive testing has shown that even if a human ear is placed against any part of the projector housing 1, the presence of this noise is imperceptible. The significance of the fan 10 is twofold. First, it can improve the convective heat transfer effect of the present invention to a certain extent without generating noise. Second, in areas with ambient temperatures above 35°C (such as South Asia, the Middle East, and some African countries), the speed of the fan 10 can be appropriately increased to meet the requirements of operation in extreme environments. However, this is not part of the present invention and is not described here.

[0085] In this embodiment, the cross-section of the outer wall of the structural support 9 is a rectangular structure, and correspondingly, the cross-section of the inner wall of the second radiator 5 is a rectangular structure. When the second radiator 5 is actually manufactured, it is often not directly made into an integral rectangular tube, but is spliced ​​into a rectangular tube by, for example, four pieces of profile radiators to reduce the difficulty of manufacturing; the cross-section of the outer wall of the structural support 9 can also be a four-segment circular arc structure, and correspondingly, the cross-section of the inner wall of the second radiator 5 is a four-segment circular arc structure. In the present invention, the cross-section of the outer wall of the structural support 9 is not limited to a rectangular and four-segment circular arc structure, and other structural forms can also be adopted. Similarly, the inner wall of the second radiator 5 is not limited to a rectangular and four-segment circular arc structure, and other structural forms can also be adopted, as long as the heat of the structural support 9 can be effectively transferred to the second radiator 5.

[0086] In this embodiment, when the inner wall of the second heat sink 5 is attached to the outer wall of the structural support 9, it needs to be filled with a thermally conductive interface material to achieve efficient heat transfer. Such materials, such as thermal grease or thermally conductive graphite sheets, are common knowledge and are not intended to be limiting. The second heat sink 5 can also be secured to the optical engine with multiple screws for increased stability. This is common knowledge in projector design and will not be elaborated upon. The heat dissipation design of the zero-noise projector in this embodiment is based on common knowledge and understanding, such as Fourier's law, fluid mechanics, and natural convection heat transfer. It also primarily involves the scientific and rational application of interdisciplinary knowledge, such as the active utilization of the chimney effect and mass transfer coupling effects. As long as "zero noise" is ensured and the materials corresponding to the heat values ​​of E1, E6, E21, and E5 are kept at a safe temperature, for example, when dissipating heat from the LCD light valve module 114, the thermal resistance R4 ≤ R2'+R3'+R4' is achieved. Similar principles apply to the heat dissipation of the LED light source 111. The goal of the zero-noise projector of the present invention can be achieved.

[0087] The basic principles, main features, and advantages of the present invention are shown and described above. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are merely illustrative of the principles of the present invention. Various changes and modifications may be made to the present invention without departing from the spirit and scope of the present invention. Such changes and modifications are intended to fall within the scope of the present invention. The scope of protection claimed in the present invention is defined by the appended claims and their equivalents.

Claims

1. A zero-noise projector, characterized in that: The projector comprises a projector housing (1), an optical system located inside the projector housing (1), an illumination section light housing (2), an imaging section light housing (3), a first radiator (4), a second radiator (5), a light source heat transfer device (6), an air guide bowl housing (7), an air guide pipe housing (8), a structural support (9), a fan (10), and a heat insulation cylinder (12); The optical system comprises an LED light source (111), a condenser (112), a collimating lens (113), an LCD light valve module (114), a field lens (115), a reflector (116), and a projection lens (117), which are arranged in sequence according to the direction of light travel. The LCD light valve module (114) comprises an APF film (1041), a transparent heat conducting plate (1042), an LCD light valve (1043), and an output polarizer (1044), which are sequentially laminated according to the direction of light travel. The length and width of the transparent heat conducting plate (1042) are a*b, the length and width of the LCD light valve (1043) are a'*b', a-a'≥3mm, b-b'≥3mm; The structural support (9) is made of metal; a plane (91) for fitting and mounting the transparent heat-conducting plate (1042) is provided on the structural support (9); a hollow square hole is provided in the center of the plane (91); the LCD light valve (1043) and the output polarizer (1044) are located in the square hole; the transparent heat-conducting plate (1042) is fitted on the plane (91) of the structural support (9); The incident end of the lighting segment light housing (2) is provided with a light source installation port, and the LED light source (111) is installed at the light source installation port; the condenser (112) and the collimating lens (113) are installed inside the lighting segment light housing (2); the emission end of the lighting segment light housing (2) is connected to the incident end of the structural support (9); The exit end of the imaging segment light housing (3) is provided with a lens mounting port, and the projection lens (117) is mounted at the lens mounting port; the field lens (115) and the reflector (116) are mounted inside the imaging segment light housing (3); the incident end of the imaging segment light housing (3) is connected to the exit end of the structural support (9); The optical system, the lighting section optical machine housing (2), the structural support (9) and the imaging section optical machine housing (3) are combined into a sealed optical machine; The second radiator (5) is a tubular profile radiator, the inner wall of the second radiator (5) is in contact with the outer wall of the structural support (9), a plurality of second heat-expanding fins are provided on the outer wall of the second radiator (5), and the second radiator (5) is provided with a second notch for avoiding the projection lens (117) and the imaging section optical housing (3); The first radiator (4) is a tubular profile radiator, the inner wall and / or outer wall of the first radiator (4) are provided with a plurality of first heat-expanding fins, and the first radiator (4) is provided with a first notch for avoiding the projection lens (117) and the imaging section optical housing (3); The second radiator (5) is placed inside the first radiator (4); the heat insulation tube (12) is arranged between the second radiator (5) and the first radiator (4); The length of the heat-insulating tube (12) is less than or equal to the length of the second heat sink (5); the heat-insulating tube (12) is provided with a third notch (122) for avoiding the projection lens (117) and the imaging section optical housing (3); The back of the LED light source (111) is attached to the middle part of the light source heat transfer device (6); the air guide bowl shell (7) is a curved bowl-shaped structure, and the air guide bowl shell (7) covers the LED light source (111), the middle part of the light source heat transfer device (6) and the incident end of the lighting section light machine housing (2), and the open end of the air guide bowl shell (7) matches the size of the rib base of the second radiator (5) and is connected; the air guide bowl shell (7) is provided with a hole or a notch for avoiding the light source heat transfer device (6), and the two ends of the light source heat transfer device (6) pass through the hole or notch on the air guide bowl shell (7) and are connected to the rib base of the first radiator (4); The fan (10) is installed at the bottom of the projector housing (1) and is located below the air guide bowl (7). The closed end of the air guide bowl (7) matches and faces the outer diameter of the fan (10) motor and is less than 5 mm away from the fan (10). The fan (10) is an axial flow fan. The air duct shell (8) is a curved cylindrical structure; the air inlet end of the air duct shell (8) matches the size of the air outlet of the fan (10) and is connected to it, and the air outlet end matches the size of the inner wall of the projector housing (1) and is connected to it, and the position of the air outlet end is higher than the air inlet end; a drainage air duct (130) is formed between the outer wall of the air duct bowl shell (7) and the inner wall of the air duct shell (8); A first natural convection air duct (131) is formed between the rib base of the second heat sink (5) and the inner wall of the heat insulation tube (12); a second natural convection air duct (132) is formed between the outer wall of the heat insulation tube (12) and the rib base of the first heat sink (4); and a third natural convection air duct (133) is formed between the rib base of the first heat sink (4) and the inner wall of the projector housing (1); The bottom of the projector housing (1) is provided with a plurality of air inlet holes; the air inlet of the fan (10) is opposite to the air inlet holes; the top of the projector housing (1) is provided with a plurality of air outlet holes; external cold air flows in through the plurality of air inlet holes, passes through the fan (10), passes through the drainage air duct (130), and passes through the first natural convection air duct (131), the second natural convection air duct (132) and the third natural convection air duct (133), and then the cold air is heated and discharged into the atmosphere from the plurality of air outlet holes.

2. A zero-noise projector according to claim 1, characterized in that: The transparent heat conducting plate (1042) is any one of sapphire glass, transparent optical crystal or glass-based single-layer graphene heat conducting plate.

3. The zero-noise projector according to claim 1, characterized in that: A plurality of acceleration holes (121) are provided in the upper middle portion of the heat-insulating tube (12); the plurality of acceleration holes (121) are waist-shaped structures, and the acceleration holes (121) are inclined upward from the inner wall of the heat-insulating tube (12) toward the outer wall thereof.

4. The zero-noise projector according to claim 1, characterized in that: When the ambient temperature is lower than 35° C., assuming that the number of blades of the fan (10) is a, the rotation speed of the fan (10) is less than 1200 / a, where the unit of the rotation speed is revolutions per minute.

5. The zero-noise projector according to claim 1, characterized in that: The cross section of the outer wall of the structural support (9) is a rectangular structure, and correspondingly, the cross section of the inner wall of the second radiator (5) is a rectangular structure; Alternatively, the cross-section of the outer wall of the structural support (9) is a four-segment circular arc structure, and correspondingly, the cross-section of the inner wall of the second radiator (5) is a four-segment circular arc structure.

6. The zero-noise projector according to claim 1, characterized in that: The light source heat transfer device (6) adopts a heat pipe or a phase change suppression plate.

Images