CN111830769A

CN111830769A - A novel cooling system for DMD of projecting apparatus

Info

Publication number: CN111830769A
Application number: CN202010777113.8A
Authority: CN
Inventors: 李军发
Original assignee: Chengdu Jimi Technology Co Ltd
Current assignee: Chengdu Jimi Technology Co Ltd; Chengdu XGIMI Technology Co Ltd
Priority date: 2020-08-05
Filing date: 2020-08-05
Publication date: 2020-10-27
Anticipated expiration: 2040-08-05
Also published as: CN111830769B

Abstract

The invention discloses a novel heat dissipation system for a DMD (digital micromirror device) of a projector, belonging to the technical field of projectors, and comprising an optical machine, a DMD element, a TEC element, a circuit board, a pressure plate, a heat dissipation seat, a plurality of fins, a piezoelectric fan and a convex hull; a DMD element is embedded on the optical machine; the DMD element is arranged on the lower surface of the circuit board; a pressing plate is pressed on the upper surface of the circuit board; openings are formed in the positions, corresponding to the DMD elements, of the pressing plate and the circuit board; a convex hull extends into the opening; the convex hull is used for transferring heat on the DMD element to the cold side end of the TEC element; the hot surface end of the TEC element is contacted with the heat dissipation seat; the heat dissipation seat is provided with a plurality of fins; the piezoelectric fan is used for cooling the fins. The novel heat dissipation system for the DMD of the projector can solve the heat dissipation problem of the DMD element under the high-brightness condition and the noise problem of a heat dissipation end.

Description

A novel cooling system for DMD of projecting apparatus

Technical Field

The invention belongs to the technical field of projectors, and particularly relates to a novel heat dissipation system for a DMD (digital micromirror device) of a projector.

Background

With the demands for the household and miniaturization of projectors, the improvement of brightness of miniaturized projection is a direction of technological breakthrough. This is accompanied by an increase in power density and an increase in the thermal load capacity of the opto-mechanical internal optics. DLP is an abbreviation for Digital Light Processing, i.e. the technique first digitally processes the image signal and then projects the Light. The digital Micromirror Device is a technology for displaying visual digital information based on the digital Micromirror element DMDDigital microminer Device developed by TI U.S. Texas instruments. DLP projection technology employs a digital micromirror wafer DMD as the main key processing element to implement digital optical processing. A DMD (digital micromirror device) is an array of multiple high-speed digital light-reflecting mirrors. The DMD is constructed of a number of small aluminum mirror surfaces, the number of mirror plates being determined by the display resolution, one mirror plate for each pixel. The object is imaged on the DMD device, each image point is sequentially scanned onto the detector through the pixel level controllable characteristic and the high-speed overturning frequency of the DMD device, and the high-speed passive point scanning imaging of the object under the visible light condition in the daytime is achieved. The increase in brightness causes a sharp increase in the luminous flux carried by the aluminum lens of the DMD, which is accompanied by the heat dissipation pressure of the DMD. How to control the temperature of the DMD at a lower temperature enables the DMD to bear higher brightness, and has great significance for realizing portability of projection.

The DMD is arranged in a groove of the optical-mechanical structure, and the heat pipe and the radiator cannot be directly attached to a heat dissipation area of the DMD. The heat dissipation area with the convex hull extruded by aluminum directly contacting the DMD is large in thermal resistance, the heat dissipation of the DMD is not ideal, and the problem of heat dissipation of the DMD under a high-brightness working condition cannot be solved. The common fan is used for cooling the radiator, and the problem of noise also exists.

Disclosure of Invention

The invention aims to provide a novel heat dissipation system for a DMD (digital micromirror device) of a projector aiming at the defects, and aims to solve the problems of heat dissipation of the DMD under a high-brightness condition, noise of a heat dissipation end and the like. In order to achieve the purpose, the invention provides the following technical scheme:

a novel heat dissipation system for a DMD (digital micromirror device) of a projector comprises an optical machine 1, a DMD element 2, a TEC element 3, a circuit board 4, a pressing plate 5, a heat dissipation seat 6, a plurality of fins 7, a piezoelectric fan and a convex hull 8; a DMD element 2 is embedded on the optical machine 1; the DMD element 2 is arranged on the lower surface of the circuit board 4; a pressing plate 5 is pressed on the upper surface of the circuit board 4; the pressing plate 5 and the circuit board 4 are provided with openings at corresponding positions of the DMD element 2; a convex hull 8 extends into the opening; the convex hull 8 is used for transferring heat on the DMD element 2 to the cold side end of the TEC element 3; the hot surface end of the TEC element 3 is contacted with a heat dissipation seat 6; the heat dissipation seat 6 is provided with a plurality of fins 7; the piezoelectric fan is used for cooling the fins 7. According to the structure, the pressing plate 5 is pressed on the upper surface of the circuit board 4, the pressing plate 5 is provided with the positioning hole, so that the pressing plate 5 and the circuit board 4 are accurately positioned, and the pressing plate 5 and the circuit board 4 are fixed on the optical machine 1 through screws; because the DMD element 2 is arranged on the lower surface of the circuit board 4, and the DMD element 2 is embedded on the optical machine 1, the pressing plate 5 and the circuit board 4 are provided with openings at corresponding positions of the DMD element 2, and the openings are used as heat dissipation channels of the DMD element 2; the DMD element 2 directly contacts the convex hull 8, transferring heat to the cold side end of the TEC elements 3 by penetrating the open convex hull 8; the convex hull 8 may be directly fixed to the cold side end of the TEC elements 3, where the cold side end of the TEC elements 3 is to be thermally isolated from the platen 5, e.g. the TEC elements 3 are supported on the platen 5 by thermal insulation; the convex hull 8 may also be fixed to a cold side end plate which is then brought into contact with the cold side end of the TEC elements 3, where the cold side end plate is thermally isolated from the pressure plate 5, e.g. the cold side end plate is supported on the pressure plate 5 by a thermal insulator. The temperature of the cold surface end of the TEC element 3 is lower, so that the DMD element 2 has a better heat dissipation effect; the hot surface end of the TEC element 3 is contacted with the heat dissipation seat 6, the heat dissipation seat 6 increases the heat dissipation area through the fins 7, and the heat dissipation efficiency of the hot surface end of the TEC element 3 is improved; the piezoelectric fan outputs high-speed and stable airflow according to actual requirements, the fins 7 are cooled, noise is low, and reliability of a hot face end of the TEC element 3 is improved.

Furthermore, the device also comprises a hot end temperature sensor and a cold end temperature sensor; the hot end temperature sensor is arranged in the heat radiation seat 6; and the cold end temperature sensor is arranged in the convex hull 8. According to the structure, the hot end temperature sensor is arranged in the heat radiating seat 6 and can monitor the hot end temperature; cold junction temperature sensor establishes in convex closure 8, can monitor cold junction temperature. Real-time monitoring of the heat dissipation system is ensured.

Further, the hot end temperature sensor and the cold end temperature sensor adopt NTC thermistors. According to the structure, the NTC thermistor is sensitive to temperature, and shows different resistance values at different temperatures.

Further, the system also comprises an AI chip for processing the data of the whole machine; the complete machine data processing AI chip is respectively and electrically connected with the TEC element 3, the piezoelectric fan, the hot end temperature sensor and the cold end temperature sensor. According to the structure, the hot end temperature sensor and the cold end temperature sensor transmit the temperature data of the heat dissipation system to the whole machine data processing AI chip, and the whole machine data processing AI chip controls the TEC element 3 and the piezoelectric fan to react; for example, when the temperature of the cold end temperature sensor is too high, the AI chip controls and reduces the temperature of the cold end of the TEC element 3; when the temperature of the hot end temperature sensor is too high, the AI chip controls the piezoelectric fan to increase the wind speed and accelerate the heat dissipation.

Further, the heat-insulating sealing ring also comprises an elastic heat-insulating sealing ring 9; the top of the elastic heat-insulation sealing ring 9 is provided with an accommodating groove; the accommodating groove is used for placing the TEC element 3, so that a seal is formed between the lower surface of the TEC element 3 and the upper surface of the pressing plate 5, and the periphery of the TEC element 3 and the side wall of the accommodating groove form a seal. According to the structure, the TEC element 3 is embedded in the accommodating groove, and the elastic heat-insulating sealing ring 9 has elasticity, so that the TEC element 3 has a certain up-down adjusting range, and the convex hull 8 can be ensured to be fully contacted with the DMD element 2; elastic heat insulation sealing ring 9 seals the lower surface of TEC element 3 and the upper surface of pressing plate 5, and separates the cold end of TEC element 3 from the heat insulation of pressing plate 5, thus avoiding cold loss.

Further, a corrugated sealing sleeve 10 is fixed on the lower surface of the heat dissipation seat 6; the corrugated sealing sleeve 10 is contacted with the upper surface of the pressure plate 5 when the heat radiating seat 6 is pressed down; the corrugated sealing sleeve 10 is used for enabling the TEC element 3 to be located in a sealed space. As can be seen from the above structure, the bellows seal 10 is used to keep the TEC elements 3 in a sealed space, reduce the entry of outside air, and reduce the condensation of dust and water on the TEC elements 3.

Furthermore, a drying agent 11 is arranged in the corrugated sealing sleeve 10. As can be seen from the above structure, the desiccant 11 ensures that the TEC elements 3 are located in the dry space, and reduces damage to the TEC elements 3 due to moisture condensation.

Further, the convex hull 8 is fixed at the cold side end of the TEC element 3; the sizes of the two ends of the convex hull 8 are larger than the size of the middle part; the side surface of the convex hull 8 and the side wall of the opening are in the gap. According to the structure, the side surface of the convex hull 8 and the side wall of the opening are in the clearance, so that the cold energy is reduced to be transmitted out from the side wall of the opening; the sizes of the two ends of the convex hull 8 are larger than the size of the middle part, so that the heat dissipation efficiency is improved.

The invention has the beneficial effects that:

1. because of the special position of the DMD element in the optical machine, the distance from the heat dissipation contact surface of the DMD element to the bottom surface of the radiator is large, the thermal resistance is large, and the heat can be only led out in a common heat dissipation mode through aluminum extrusion with a large heat exchange area and large air flow. After the heat is led out, the cold surface end of the TEC element, which is lower than the ring temperature, is connected with the heat dissipation contact surface of the DMD through the convex hull, so that the temperature of the DMD element is maintained at a lower temperature, and the heat dissipation requirement of the DMD element under the conditions of high brightness and high temperature is met.

2. At the hot side end aluminium of TEC component crowded department, abandoned traditional direct current fan, adopted neotype piezoelectric fan structure, made piezoelectric fan and aluminium crowded an organic whole, and owing to do not have rotary mechanism, promoted the reliable and stable nature, owing to cancelled the fan simultaneously, reduced the whole noise of product.

3. NTC thermistors are arranged in the cold end and the hot end of the TEC element, data algorithm analysis is carried out according to the real-time temperature of the cold end and the hot end, the output power of the cold end TEC element and the power of the piezoelectric fan at the hot end are adjusted, and the temperature of the DMD element is maintained in the optimal working state.

Drawings

FIG. 1 is a schematic structural view of the present invention;

in the drawings: the device comprises a light machine 1, a DMD element 2, a TEC element 3, a circuit board 4, a pressing plate 5, a heat dissipation seat 6, a fin 7, a convex hull 8, an elastic heat insulation sealing ring 9, a corrugated sealing sleeve 10 and a drying agent 11.

Detailed Description

The present invention will be described in further detail below with reference to the drawings and the embodiments, but the present invention is not limited to the following examples.

The first embodiment is as follows:

see figure 1. A novel heat dissipation system for a DMD (digital micromirror device) of a projector comprises an optical machine 1, a DMD element 2, a TEC element 3, a circuit board 4, a pressing plate 5, a heat dissipation seat 6, a plurality of fins 7, a piezoelectric fan and a convex hull 8; a DMD element 2 is embedded on the optical machine 1; the DMD element 2 is arranged on the lower surface of the circuit board 4; a pressing plate 5 is pressed on the upper surface of the circuit board 4; the pressing plate 5 and the circuit board 4 are provided with openings at corresponding positions of the DMD element 2; a convex hull 8 extends into the opening; the convex hull 8 is used for transferring heat on the DMD element 2 to the cold side end of the TEC element 3; the hot surface end of the TEC element 3 is contacted with a heat dissipation seat 6; the heat dissipation seat 6 is provided with a plurality of fins 7; the piezoelectric fan is used for cooling the fins 7. According to the structure, the pressing plate 5 is pressed on the upper surface of the circuit board 4, the pressing plate 5 is provided with the positioning hole, so that the pressing plate 5 and the circuit board 4 are accurately positioned, and the pressing plate 5 and the circuit board 4 are fixed on the optical machine 1 through screws; because the DMD element 2 is arranged on the lower surface of the circuit board 4, and the DMD element 2 is embedded on the optical machine 1, the pressing plate 5 and the circuit board 4 are provided with openings at corresponding positions of the DMD element 2, and the openings are used as heat dissipation channels of the DMD element 2; the DMD element 2 directly contacts the convex hull 8, transferring heat to the cold side end of the TEC elements 3 by penetrating the open convex hull 8; the convex hull 8 may be directly fixed to the cold side end of the TEC elements 3, where the cold side end of the TEC elements 3 is to be thermally isolated from the platen 5, e.g. the TEC elements 3 are supported on the platen 5 by thermal insulation; the convex hull 8 may also be fixed to a cold side end plate which is then brought into contact with the cold side end of the TEC elements 3, where the cold side end plate is thermally isolated from the pressure plate 5, e.g. the cold side end plate is supported on the pressure plate 5 by a thermal insulator. The temperature of the cold surface end of the TEC element 3 is lower, so that the DMD element 2 has a better heat dissipation effect; the hot surface end of the TEC element 3 is contacted with the heat dissipation seat 6, the heat dissipation seat 6 increases the heat dissipation area through the fins 7, and the heat dissipation efficiency of the hot surface end of the TEC element 3 is improved; the piezoelectric fan outputs high-speed and stable airflow according to actual requirements, the fins 7 are cooled, noise is low, and reliability of a hot face end of the TEC element 3 is improved.

Example two:

The device also comprises a hot end temperature sensor and a cold end temperature sensor; the hot end temperature sensor is arranged in the heat radiation seat 6; and the cold end temperature sensor is arranged in the convex hull 8. According to the structure, the hot end temperature sensor is arranged in the heat radiating seat 6 and can monitor the hot end temperature; cold junction temperature sensor establishes in convex closure 8, can monitor cold junction temperature. Real-time monitoring of the heat dissipation system is ensured.

Example three:

And the hot end temperature sensor and the cold end temperature sensor adopt NTC thermistors. According to the structure, the NTC thermistor is sensitive to temperature, and shows different resistance values at different temperatures.

The system also comprises a complete machine data processing AI chip; the complete machine data processing AI chip is respectively and electrically connected with the TEC element 3, the piezoelectric fan, the hot end temperature sensor and the cold end temperature sensor. According to the structure, the hot end temperature sensor and the cold end temperature sensor transmit the temperature data of the heat dissipation system to the whole machine data processing AI chip, and the whole machine data processing AI chip controls the TEC element 3 and the piezoelectric fan to react; for example, when the temperature of the cold end temperature sensor is too high, the AI chip controls and reduces the temperature of the cold end of the TEC element 3; when the temperature of the hot end temperature sensor is too high, the AI chip controls the piezoelectric fan to increase the wind speed and accelerate the heat dissipation.

Also comprises an elastic heat-insulating sealing ring 9; the top of the elastic heat-insulation sealing ring 9 is provided with an accommodating groove; the accommodating groove is used for placing the TEC element 3, so that a seal is formed between the lower surface of the TEC element 3 and the upper surface of the pressing plate 5, and the periphery of the TEC element 3 and the side wall of the accommodating groove form a seal. According to the structure, the TEC element 3 is embedded in the accommodating groove, and the elastic heat-insulating sealing ring 9 has elasticity, so that the TEC element 3 has a certain up-down adjusting range, and the convex hull 8 can be ensured to be fully contacted with the DMD element 2; elastic heat insulation sealing ring 9 seals the lower surface of TEC element 3 and the upper surface of pressing plate 5, and separates the cold end of TEC element 3 from the heat insulation of pressing plate 5, thus avoiding cold loss.

A corrugated sealing sleeve 10 is fixed on the lower surface of the heat dissipation seat 6; the corrugated sealing sleeve 10 is contacted with the upper surface of the pressure plate 5 when the heat radiating seat 6 is pressed down; the corrugated sealing sleeve 10 is used for enabling the TEC element 3 to be located in a sealed space. As can be seen from the above structure, the bellows seal 10 is used to keep the TEC elements 3 in a sealed space, reduce the entry of outside air, and reduce the condensation of dust and water on the TEC elements 3.

The corrugated sealing sleeve 10 is internally provided with a drying agent 11. As can be seen from the above structure, the desiccant 11 ensures that the TEC elements 3 are located in the dry space, and reduces damage to the TEC elements 3 due to moisture condensation.

The convex hull 8 is fixed at the cold side end of the TEC element 3; the sizes of the two ends of the convex hull 8 are larger than the size of the middle part; the side surface of the convex hull 8 and the side wall of the opening are in the gap. According to the structure, the side surface of the convex hull 8 and the side wall of the opening are in the clearance, so that the cold energy is reduced to be transmitted out from the side wall of the opening; the sizes of the two ends of the convex hull 8 are larger than the size of the middle part, so that the heat dissipation efficiency is improved.

The above description is only a preferred embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications of equivalent structures and equivalent processes, which are made by using the contents of the present specification and the accompanying drawings, or directly or indirectly applied to other related technical fields, are included in the scope of the present invention.

Claims

1. A novel cooling system for DMD of projector, its characterized in that: the device comprises an optical machine (1), a DMD element (2), a TEC element (3), a circuit board (4), a pressing plate (5), a heat dissipation seat (6), a plurality of fins (7), a piezoelectric fan and a convex hull (8); a DMD element (2) is embedded on the optical machine (1); the DMD element (2) is arranged on the lower surface of the circuit board (4); a pressing plate (5) is pressed on the upper surface of the circuit board (4); the pressing plate (5) and the circuit board (4) are provided with openings at corresponding positions of the DMD element (2); a convex hull (8) extends into the opening; the convex hull (8) is used for transferring heat on the DMD element (2) to the cold side end of the TEC element (3); the hot surface end of the TEC element (3) is contacted with a heat dissipation seat (6); the heat dissipation seat (6) is provided with a plurality of fins (7); the piezoelectric fan is used for cooling the fins (7).

2. The new heat dissipation system for a DMD of a projector according to claim 1, wherein: the device also comprises a hot end temperature sensor and a cold end temperature sensor; the hot end temperature sensor is arranged in the heat dissipation seat (6); and the cold end temperature sensor is arranged in the convex hull (8).

3. The new heat dissipation system for a DMD of a projector according to claim 2, wherein: and the hot end temperature sensor and the cold end temperature sensor adopt NTC thermistors.

4. The new heat dissipation system for a DMD of a projector according to claim 2, wherein: the system also comprises a complete machine data processing AI chip; the complete machine data processing AI chip is respectively and electrically connected with the TEC element (3), the piezoelectric fan, the hot end temperature sensor and the cold end temperature sensor.

5. The new heat dissipation system for a DMD of a projector according to claim 1, wherein: the heat-insulating sealing ring also comprises an elastic heat-insulating sealing ring (9); the top of the elastic heat-insulation sealing ring (9) is provided with an accommodating groove; the accommodating groove is used for placing the TEC element (3), so that a seal is formed between the lower surface of the TEC element (3) and the upper surface of the pressing plate (5), and the periphery of the TEC element (3) and the side wall of the accommodating groove form a seal.

6. The novel heat dissipation system for DMDs of projectors of claim 5, wherein: a corrugated sealing sleeve (10) is fixed on the lower surface of the heat dissipation seat (6); the corrugated sealing sleeve (10) is in contact with the upper surface of the pressure plate (5) when the heat dissipation seat (6) is pressed downwards; the corrugated sealing sleeve (10) is used for enabling the TEC element (3) to be located in the sealed space.

7. The novel heat dissipation system for DMDs of projectors according to claim 6, wherein: and a drying agent (11) is arranged in the corrugated sealing sleeve (10).

8. The new heat dissipation system for a DMD of a projector according to claim 1, wherein: the convex hull (8) is fixed at the cold surface end of the TEC element (3); the sizes of the two ends of the convex hull (8) are larger than the size of the middle part; the side surface of the convex hull (8) and the side wall of the opening are in the gap.