Handheld colored low-light night vision remote evidence obtaining device for police

Abstract

The invention relates to the technical field of video recording equipment, and discloses a handheld police colored low-light night vision long-distance evidence obtaining device which comprises a video recording instrument body, a base is embedded in the bottom of the video recording instrument body, and a miniature cooling fan communicated with an inner cavity of the video recording instrument body is arranged at one end of the base. An air outlet communicated with the micro cooling fan is formed in the side wall of the base, and an air inlet is formed in the side wall of the video recording instrument body; the adjusting assembly is used for adjusting the sizes of the air outlet and the air inlet. Through folding of the handle and secondary pushing of the first temperature control driving element, self-adaptive adjustment of the air inlet and the air outlet along with the use state and the temperature is achieved, when the handle is folded, the air opening is closed, and dust and water vapor are prevented from invading; when the handle is unfolded, a small opening degree is opened to meet basic heat dissipation and energy conservation; after the temperature rises, the ventilation quantity is increased by automatically pushing to a large opening degree so as to cope with peak thermal load.

Description

Technical Field

[0001] This invention relates to the field of video recording equipment technology, and in particular to a handheld police-use color low-light night vision long-distance evidence collection device. Background Technology

[0002] Police nighttime evidence collection devices are handheld night vision devices that integrate video recording and photography functions. They are mainly used by law enforcement personnel such as public security officers and armed police officers to record videos and capture images of distant targets at night or in low-light environments. With the development of optoelectronic imaging technology, color low-light night vision technology can output color images under extremely low light conditions, which has higher target recognition and scene restoration capabilities compared to traditional black and white low-light night vision. Long-distance observation relies on the combination of telephoto optical lenses and high-sensitivity image sensors, and by increasing the optical aperture and improving signal gain, target capture at hundreds of meters or even kilometers can be achieved. At present, such devices with color low-light night vision and long-distance recording functions have been gradually promoted and applied in police operations. They mainly include core components such as optical lenses, image sensors, image signal processors, video encoding and storage modules, displays, and batteries.

[0003] In actual operation, such devices often need to record continuously for long periods of time and may face harsh environments such as high temperature and high humidity. Continuous high-load operation causes the internal main control chip, image sensor and video encoding module to generate a lot of heat. If the heat cannot be dissipated in time, it will cause increased image noise, decreased frame rate and even device overheat protection to force shutdown, seriously affecting the reliability of evidence collection. Existing devices usually use passive or active heat dissipation structures such as shell heat dissipation holes, heat sinks or micro fans, but the opening of the air inlet and outlet is often fixed, and it is impossible to dynamically adjust the ventilation volume according to the actual internal temperature of the device. This results in the fan still running at a high speed under low temperature conditions, causing unnecessary power consumption, or insufficient ventilation under high temperature conditions, which cannot meet the heat dissipation requirements. In addition, the internal air duct design of the device is mostly single and fixed. The airflow often flows and is discharged along a fixed path, which can easily form a thermal boundary layer accumulation in local areas, resulting in weakened heat dissipation effect. This leads to uneven temperature distribution on the surface of heat-generating elements and limits the improvement of overall heat dissipation efficiency. Summary of the Invention

[0004] The technical problem to be solved by the present invention is that the opening of the air inlet and outlet of the existing device is fixed and the airflow path is single, which makes it impossible to dynamically adjust the ventilation volume according to the temperature. This results in both energy waste at low temperatures and insufficient heat dissipation at high temperatures. At the same time, the fixed air duct is prone to the accumulation of thermal boundary layer, causing uneven heat dissipation. To address this, we propose a handheld police color low-light night vision long-distance evidence collection device.

[0005] To achieve the above objectives, this application adopts the following technical solution: a handheld police color low-light night vision long-distance evidence collection device, including a camera body, a base embedded in the bottom of the camera body, a miniature heat dissipation fan communicating with the inner cavity of the camera body at one end of the base, an air outlet communicating with the miniature heat dissipation fan on the side wall of the base, and an air inlet on the side wall of the camera body. It also includes an adjustment assembly for adjusting the size of the air outlet and the air inlet. The adjustment assembly includes an air inlet hood plate set on the side wall of the camera body. The air inlet is opened on the air inlet hood plate. An arc-shaped adjustment plate is rotatably set on the inner side of the air inlet hood plate. The arc-shaped adjustment plate is provided with a through hole corresponding to the air inlet. A baffle plate is set on the inner side of the air outlet. A rectangular adjustment plate corresponding to the baffle plate is movably set on the inner side of the base. The rectangular adjustment plate and the baffle plate are provided with corresponding through holes. An air volume adjustment mechanism is provided on the base for driving the rectangular adjustment plate to move and the arc-shaped adjustment plate to rotate. The air inlet of the miniature cooling fan is equipped with a guide frame, in which a guide plate is rotatably mounted. The guide frame is equipped with an alternating swing mechanism for driving the guide plate to swing back and forth. Both the airflow adjustment mechanism and the alternating oscillation mechanism are thermally driven mechanisms, and their driving energy comes from the heat inside the camera body.

[0006] Preferably, the air volume adjustment mechanism includes a second transverse frame movably mounted on the base, one end of a rectangular adjustment plate connected to the second transverse frame, a first rack at the end of the second transverse frame, a first gear corresponding to the first rack at the bottom of the arc-shaped adjustment plate, and a first temperature control drive element on one side of the second transverse frame.

[0007] Preferably, the first temperature control drive element is a two-way shape memory alloy spring.

[0008] Preferably, a handle is rotatably provided at the bottom of the base, a second gear is provided on the handle, a first transverse frame is movably provided on the base above the handle, the side wall of the first transverse frame is evenly provided with gear teeth that mesh with the second gear, the first temperature control drive element is installed between the second transverse frame and the first transverse frame, and a push rod for pushing the second transverse frame to move is provided at one end of the first transverse frame near the second transverse frame.

[0009] Preferably, there are two handles, which are arranged back to back. When the axis of the handle is parallel to the axis of the camera body, the air outlet and air inlet are closed. When the axis of the handle is perpendicular to the axis of the camera body, the air outlet and air inlet are open.

[0010] Preferably, the first transverse frame is provided with a guide rod corresponding to the first temperature control drive element at one end near the second transverse frame, and both the second transverse frame and the first temperature control drive element are movably sleeved on the guide rod.

[0011] Preferably, the alternating swing mechanism includes cooling holes at both ends of the guide frame, a second rack is movably arranged on the inner side of the side wall of the guide frame, a third gear meshing with the second rack is provided at the end of the guide plate, traction plates corresponding to the cooling holes are respectively installed at both ends of the second rack, and a second temperature control drive element is installed between the side wall of the traction plate and the inner wall of the cooling hole.

[0012] Preferably, the second temperature control drive element is a single-pass shape memory alloy spring, and when the single-pass shape memory alloy spring is heated to its phase transition temperature, it automatically contracts from an elongated state to a preset high-temperature shape. The single-pass shape memory alloy springs at both ends are configured such that, initially, one end of the single-pass shape memory alloy spring is in a contracted state and hidden in the cooling hole, while the other end of the single-pass shape memory alloy spring is in an extended state and exposed in the inner cavity of the camera body.

[0013] Preferably, the air guide frame is provided with a second air pipe that connects the cooling hole to the outside and a first air pipe that connects the cooling hole to a miniature radiator fan.

[0014] Preferably, dustproof nets are provided in the second air pipe, air outlet and air inlet.

[0015] The technical effects and advantages of this invention are as follows: In this invention, a foldable handle is linked to the air inlet and outlet, and a first temperature-controlled drive element is used to achieve secondary pushing. When the handle is folded, the air inlet and outlet are completely closed, which can effectively prevent dust, sand, and rainwater from entering in the field environment, reduce the risk of dust accumulation in the air duct during standby, and extend the service life of the equipment. When the handle is unfolded, the air outlet and air inlet are opened to a small degree, which meets the basic heat dissipation requirements under normal evidence collection tasks, while avoiding the excess energy consumption caused by large air volume, which is conducive to extending battery life. When the heat generated inside the device increases due to long-term continuous recording or high ambient temperature, the first temperature-controlled drive element near the heat-generating element deforms due to heat, further pushing the air inlet and outlet to a large degree, significantly increasing the ventilation volume to cope with peak heat load. This solution combines the user's active operation with the device's passive temperature control, which simplifies the operation steps and achieves the energy-saving effect of automatic air volume adjustment with temperature, making it suitable for the long-term task requirements of police night vision evidence collection equipment in complex field environments.

[0016] In this invention, an adjustable-angle guide plate is installed near the air outlet. Two second temperature-controlled driving elements alternately heat and contract to drive the guide plate to swing back and forth. This swinging motion causes the airflow direction inside the device to change periodically, thereby continuously changing the scouring path of the airflow on the surface of the heating element. Compared with a fixed air outlet direction, the swinging air outlet can avoid the local heat accumulation phenomenon formed by the airflow flowing along the same path for a long time, allowing the airflow to cover more heat dissipation surface, reducing flow dead zones, and forcing the thermal boundary layer to be continuously destroyed and re-established during the direction change process, thereby maintaining a high heat exchange efficiency. For handheld police night vision evidence collection devices, this design does not require additional motors or sensors, and is driven entirely by the device's own hot airflow. It achieves zero-energy adaptive airflow path optimization, improves the heat dissipation stability in long-term continuous evidence collection tasks, and reduces the risk of image noise or device frequency reduction caused by local high temperature. Attached Figure Description

[0017] The disclosure of this invention is illustrated with reference to the accompanying drawings. It should be understood that the drawings are for illustrative purposes only and are not intended to limit the scope of protection of this invention. In the drawings, the same reference numerals are used to refer to the same parts: Figure 1 This is a schematic diagram of the structure of the present invention in its folded state; Figure 2 For the present invention Figure 1 A structural diagram from the bottom perspective; Figure 3 This is a schematic diagram of the structure of the present invention in its unfolded state; Figure 4 This is a structural diagram of the base, air intake shroud, and camera body of the present invention in a disassembled state; Figure 5 This is a structural diagram of the arc-shaped adjusting plate and the air intake cover plate of the present invention in a disassembled state; Figure 6 This is a partial cross-sectional structural diagram of the base of the present invention; Figure 7 For the present invention Figure 6 A structural diagram from another perspective based on the above; Figure 8 This is a schematic diagram of the structure of the handle, the air guide, and the first temperature control drive element of the present invention in a coordinated state. Figure 9 This is a structural diagram of the air guide frame, air guide plate, and miniature cooling fan of the present invention in a disassembled state; Figure 10 For the present invention Figure 9 A structural diagram from the bottom perspective.

[0018] Legend: 1. Camera body; 2. Air intake shroud; 3. Base; 4. Handle; 5. Second temperature control drive element; 6. First air pipe; 7. Hidden slot; 8. Air outlet; 9. Air inlet; 10. Flow guide; 11. Cavity; 12. Arc-shaped adjustment plate; 13. First gear; 14. Through port; 15. Flow guide plate; 16. Miniature cooling fan; 17. Rectangular adjustment plate; 18. Cut-off plate; 19. First rack; 20. First transverse frame; 21. Second transverse frame; 22. First temperature control drive element; 23. Guide rod; 24. Top rod; 25. Through hole; 26. Second gear; 27. Gear teeth; 28. Second air pipe; 29. ​​Cooling hole; 30. Second rack; 31. Third gear; 32. Traction plate. Detailed Implementation

[0019] It is readily understood that, based on the technical solution of this invention, those skilled in the art can propose various interchangeable structural methods and implementations without altering the essential spirit of the invention. Therefore, the following detailed embodiments and accompanying drawings are merely illustrative examples of the technical solution of this invention and should not be considered as the entirety of the invention or as limitations or restrictions on the technical solution of this invention.

[0020] like Figures 1-10 As shown, a handheld police-grade color low-light night vision long-range evidence collection device includes a camera body 1. It belongs to a handheld color low-light night vision recording device integrating optical imaging, photoelectric conversion, image processing, display storage, and power management. Its core components, in order of functional chain, include: Large-aperture telephoto optical lens assembly is used to collect faint ambient light reflected from distant targets, such as moonlight, starlight, or atmospheric glow, in low-light environments at night. Its large aperture and long focal length design provide basic optical gain for long-distance observation.

[0021] Low-light image sensors, which are CMOS or image intensifier coupled with CMOS, are used to convert optical images into raw electrical signals and are the core photoelectric conversion element for realizing imaging under extremely low light conditions.

[0022] The image signal processor or main control chip is responsible for running digital algorithms such as denoising, automatic gain control, detail enhancement and color restoration on the original electrical signal to reconstruct a full-color digital video image.

[0023] The video encoding and storage module is used to compress the processed digital video stream in real time and write it to the built-in solid-state storage medium.

[0024] The display module typically includes a miniature display screen for live view and an onboard LCD screen for playback and menu operation. It may also be equipped with an electronic viewfinder to adapt to bright light environments.

[0025] The power supply and power management module consists of a removable high-capacity lithium battery pack and a charge / discharge management circuit, providing the device with power for long-term operation.

[0026] In addition, it includes a handheld housing that integrates all the above components, as well as control buttons, status indicators and data transmission interfaces arranged on the housing.

[0027] The specific selection of the above-mentioned components, the setting of optical parameters, the circuit design and the integration process have mature applications and various commercial products in this field, and are within the scope of existing technology. Therefore, their specific structures and implementation methods will not be elaborated here, and the accompanying drawings will not be shown separately.

[0028] Unlike existing technologies, a hollow base 3 is embedded at the bottom of the camera body 1. A hidden groove 7 is provided at the bottom of the base 3. Handles 4 are rotatably provided at both ends of the inner side of the hidden groove 7. The two handles 4 are arranged opposite to each other and can be flipped out for easy gripping.

[0029] A miniature cooling fan 16 communicating with the inner cavity of the camera body 1 is provided at the top of one end of the base 3. An air outlet 8 communicating with the miniature cooling fan 16 is provided on the side wall of the base 3. A dustproof net is provided at the air outlet 8. An arc-shaped air intake shroud 2 is provided on the side wall of the camera body 1 away from the miniature cooling fan 16. An air inlet 9 is provided on the air intake shroud 2. A dustproof net is provided on the air inlet 9. An arc-shaped adjustment plate 12 is rotatably provided on the inner side of the air intake shroud 2. The base 2 is provided with an opening 14 corresponding to the air inlet 9. The size of the air inlet 9 can be adjusted by the overlapping area of ​​the opening 14 and the air inlet 9. A baffle 18 is provided inside the air outlet 8. A rectangular adjustment plate 17 corresponding to the baffle 18 is movably provided inside the base 3. The rectangular adjustment plate 17 and the baffle 18 are provided with corresponding through holes 25. The size of the air outlet 8 can be adjusted by the overlapping area of ​​the through holes 25 on the rectangular adjustment plate 17 and the baffle 18.

[0030] Furthermore, the base 3 is provided with an airflow adjustment mechanism for driving the rectangular adjustment plate 17 to move and the arc-shaped adjustment plate 12 to rotate. As a preferred embodiment, the airflow adjustment mechanism includes a cavity 11 located at the top of one end of the base 3 and communicating with the inner cavity of the camera body 1. A second transverse frame 21 is movably arranged in the cavity 11. One end of the rectangular adjustment plate 17 is connected to the second transverse frame 21 through a connecting rod or similar structure. A first rack 19 is provided at the end of the second transverse frame 21. A first gear 13 corresponding to the first rack 19 is installed at the bottom of the arc-shaped adjustment plate 12. A first temperature control drive element 22 is provided on one side of the second transverse frame 21. The first temperature control drive element 22 is preferably a two-way shape memory alloy spring.

[0031] To facilitate the initial opening of the air outlet 8 and air inlet 9 when the handle 4 is unfolded, a second gear 26 is installed on one of the handles 4. A first transverse frame 20 is movably mounted above the handle 4 at one end of the cavity 11. The sidewall of the first transverse frame 20 is evenly provided with gear teeth 27 that mesh with the second gear 26. A first temperature control drive element 22 is installed between the second transverse frame 21 and the first transverse frame 20. To increase the stability of the first temperature control drive element 22 and the second transverse frame 21, a guide rod 23 corresponding to the first temperature control drive element 22 is provided at the end of the first transverse frame 20 near the second transverse frame 21. Both the first temperature control drive element 21 and the second temperature control drive element 22 are movably mounted on the guide rod 23. At the same time, the connecting rod structure between the rectangular adjustment plate 17 and the second transverse frame 21 can pass through the first transverse frame 20 and be movably connected at the passage. The first transverse frame 20 is provided with a top rod 24 for pushing the second transverse frame 21 to move. When the axis of the handle 4 is parallel to the axis of the camera body 1, the air outlet 8 and the air inlet 9 are closed. When the axis of the handle 4 is perpendicular to the axis of the camera body 1, the air outlet 8 and the air inlet 9 are open. The first temperature control drive element 22 is used to push the second transverse frame 21 to move a second time.

[0032] A guide frame 10 is provided at the air inlet of the miniature cooling fan 16. The guide frame 10 is frame-shaped with a hollow inner structure. Multiple guide plates 15 are rotatably arranged in the guide frame 10. An alternating swing mechanism for driving the guide plates 15 to swing back and forth is provided on the guide frame 10. In a preferred embodiment, the alternating swing mechanism includes cooling holes 29 located on the inner sides of both ends of the guide frame 10. A second rack 30 is movably guided on the inner side of the side wall of the guide frame 10. A third gear 31 extending to the inner side of the side wall of the guide plate 15 and meshing with the second rack 30 is provided at the end of the guide plate 15. Traction plates 32 corresponding to the cooling holes 29 are respectively installed at both ends of the second rack 30. A second temperature control drive element 5 is installed between the side wall of 2 and the inner wall of the cooling hole 29. The second temperature control drive element 5 is preferably a single-pass shape memory alloy spring. When the single-pass shape memory alloy spring is heated to its phase transition temperature, it automatically contracts from an elongated state to a preset high-temperature shape. The single-pass shape memory alloy springs at both ends are configured as follows: initially, one end of the single-pass shape memory alloy spring is in a contracted state and hidden in the cooling hole 29, while the other end of the single-pass shape memory alloy spring is in an extended state and exposed in the inner cavity of the camera body 1. The number of cooling holes 29 at each end of the guide frame 10 is at least one, which is adjusted according to the number of guide plates 15 to ensure that the guide plates 15 can be driven to flip.

[0033] In order to quickly cool down the second temperature control drive element 5 entering the cooling hole 29, a second air pipe 28 connecting the cooling hole 29 to the outside and a first air pipe 6 connecting the cooling hole 29 to the miniature cooling fan 16 are provided on the air guide frame 10. When the miniature cooling fan 16 is running, outside air can enter through the second air pipe 28 and then exit through the first air pipe 6 to achieve heat exchange. A dustproof screen is also provided in the second air pipe 28 that connects to the outside.

[0034] It should be noted that the largest heat source in this invention is the main control chip or dedicated image signal processor, which undertakes the tasks of sensor data acquisition, complex ISP algorithms, H.264 / H.265 video encoding, and overall system control. It has the highest power consumption and the most concentrated heat generation. Therefore, the dual-path memory alloy spring is close to the heat sink of the main control chip or ISP chip to conduct heat, so as to achieve a more direct and sensitive temperature control response.

[0035] Working principle: When not in use, the axis of handle 4 is parallel to the axis of the camera body 1. At this time, handle 4 is hidden and folded in the hidden groove 7. The through hole 25 on the rectangular adjustment plate 17 is offset from the through hole 25 on the baffle plate 18, thus the air outlet 8 is blocked. The through hole 14 on the arc-shaped adjustment plate 12 is offset from the air inlet 9 on the air inlet cover plate 2, thus the air inlet 9 is also blocked, preventing dust, moisture and other substances from entering the camera body 1.

[0036] In use, the handle 4 is flipped out, with the two handles 4 facing away from each other for easy gripping and to increase the stability of the handle 4 and the camera body 1. At this time, the axis of the handle 4 is perpendicular to the axis of the camera body 1. Due to the flipping of the handle 4, the second gear 26 on one of the handles 4 will drive the first transverse frame 20 to move through the gear teeth 27. The first transverse frame 20 pushes the second transverse frame 21 to move through the push rod 24. The second transverse frame 21 drives the rectangular adjustment plate 17 to move. At the same time, the second transverse frame 21 realizes the rotation of the arc-shaped adjustment plate 12 through the cooperation of the first rack 19 and the first gear 13. At this time, the through hole 25 on the rectangular adjustment plate 17 coincides with the through hole 25 on the intercepting plate 18, so that the miniature cooling fan 16 is connected to the outside. The opening 14 also coincides with the air inlet 9, so that the air inlet 9 connects the outside with the inner cavity of the camera body 1. The operation of the miniature cooling fan 16 realizes heat exchange and heat dissipation.

[0037] When the temperature rises and the airflow of the air outlet 8 and air inlet 9 is insufficient to meet the heat dissipation requirements, the first temperature control drive element 22 expands due to heat, further pushing the second transverse frame 21. As a result, the overlapping area of ​​the through-hole 14 and the air inlet 9 increases, and the displacement of the second transverse frame 21 will cause the rectangular adjustment plate 17 to continue to move. As a result, the overlapping area of ​​the through hole 25 on the rectangular adjustment plate 17 and the baffle plate 18 will also increase. After the opening of the air outlet 8 and the air inlet 9 increases, the ventilation resistance of the air duct decreases accordingly. Under the condition that the speed of the miniature cooling fan 16 remains unchanged, the airflow driven by the miniature cooling fan 16 is easier to pass through the air duct, thereby significantly increasing the cooling airflow flowing through the camera body 1 per unit time, thus enhancing the heat dissipation effect.

[0038] Furthermore, during heat dissipation, the second temperature control drive element 5, exposed outside the cooling hole 29 and in an extended state, contracts when heated by the hot airflow, thereby pushing the corresponding traction plate 32 to move. The traction plate 32 drives the second rack 30 and the traction plate 32 at the other end to move synchronously. The second rack 30 drives the guide plate 15 to flip to one side through the third gear 31. The second temperature control drive element 5, which is hidden in the cooling hole 29 and in a contracted state at the other end, is pulled out of the cooling hole 29 by the traction plate 32. The second temperature control drive element 5, which contracts due to heat, then hides back into the corresponding cooling hole 29, and the cooling hole 29 is blocked by the traction plate 32. The pulled-out second temperature control drive element 5 also gradually contracts due to the heating of the hot airflow, thereby causing the guide plate 15 to flip to the other side. This reciprocating motion causes the guide plate 15 to swing back and forth, and the swinging motion causes the airflow direction inside the equipment to change periodically, thereby maintaining By continuously changing the scouring path of the airflow on the surface of the heating element, compared with a fixed air outlet direction, the oscillating air outlet can avoid the local heat accumulation phenomenon formed by the airflow flowing along the same path for a long time, allowing the airflow to cover more heat dissipation surfaces, reducing flow dead zones, and forcing the thermal boundary layer to be continuously destroyed and re-established during the direction change process, thereby maintaining a high heat exchange efficiency until the temperature drop is insufficient to cause the second temperature control drive element 5 to deform. It should be noted that the first air pipe 6 connected to the cooling hole 29 will continuously draw hot air from the inside of the cooling hole 29 due to the operation of the miniature cooling fan 16, while the outside air enters the cooling hole 29 through the second air pipe 28 to achieve heat exchange, thereby accelerating the cooling of the second temperature control drive element 5, which makes it easier for the second temperature control drive element 5 at the other end to shrink when heated, stretching the cooled second temperature control drive element 5 out of the cooling hole 29, so as to quickly realize the reciprocating oscillation of the second temperature control drive element 5.

[0039] It should be noted that the thermal deformation temperature range of the first temperature control drive element 22 is determined based on the actual operating temperature rise characteristics of the main control chip or image signal processor inside the camera body 1. The martensitic completion temperature of the dual-path shape memory alloy spring is set to 35°C to 40°C to ensure that the dual-path shape memory alloy spring is in a low-temperature contraction state when the camera body 1 is started at room temperature or low temperature. The air outlet 8 and air inlet 9 maintain a basic ventilation volume with a small opening after the handle 4 is unfolded. The austenitic initiation temperature of the dual-path shape memory alloy spring is set to 55°C, that is, when the surface temperature of the heating element inside the camera body 1 reaches 55°C, the dual-path shape memory alloy spring begins to undergo phase transformation and extension. The air outlet 8 and air inlet 9 are gradually expanded. The austenitic completion temperature of the dual-pass shape memory alloy spring is set to 65°C. At this time, the dual-pass shape memory alloy spring is fully deformed to a high-temperature extended state, and the air outlet 8 and air inlet 9 reach their maximum opening. The above temperature range is slightly higher than the steady-state operating temperature of the camera body 1 under normal conditions. The secondary push is only triggered when there is a significant internal temperature rise due to long-term continuous recording or high-temperature environment. This achieves adaptive adjustment of low temperature and small air volume for energy saving and high temperature and large air volume for strong heat dissipation. The dual-pass shape memory alloy spring material is TiNi-based dual-pass shape memory alloy. The above temperature window is precisely controlled by adjusting the nickel-titanium ratio and heat treatment process.

[0040] The martensitic completion temperature of the single-pass shape memory alloy spring is set to 25°C to 30°C, ensuring that the single-pass shape memory alloy spring, exposed in its extended state after low-temperature startup of the camera body 1, is in its initial position. The austenitic initial temperature of the single-pass shape memory alloy spring is set to 45°C. When the internal hot airflow temperature of the camera body 1 reaches 45°C, the single-pass shape memory alloy spring exposed to the hot airflow begins to contract, pulling the guide plate 15 to tilt to one side. The austenitic completion temperature of the single-pass shape memory alloy spring is set to 55°C. At this point, the single-pass shape memory alloy spring is fully contracted, and the guide plate 15 swings to its extreme position in that direction. Subsequently, the single-pass shape memory alloy... The spring is removed from the heat source and enters the cooling hole 29. Under the heat dissipation effect of the cooling hole 29, the temperature gradually drops below the martensitic phase transformation point, about 30°C to 35°C. At this time, the single-pass shape memory alloy spring is still in a contracted state. When the other single-pass shape memory alloy spring is heated and contracted, it is passively stretched to an elongated state to prepare for the next contraction. The two single-pass shape memory alloy springs alternately experience the cycle of heating and contraction and cooling and reset. The oscillation frequency increases with the increase of the internal temperature of the camera body 1. The material of the single-pass shape memory alloy spring is TiNi-based single-pass shape memory alloy. The phase transformation hysteresis range is controlled between 10°C and 15°C to ensure that the heating and cooling process forms a stable self-excited oscillation.

[0041] The technical scope of this invention is not limited to the content described above. Those skilled in the art can make various modifications and variations to the above embodiments without departing from the technical concept of this invention, and all such modifications and variations should fall within the protection scope of this invention.

Claims

1. A handheld police-grade color low-light night vision long-range evidence collection device, characterized in that, The device includes a camera body, a base is embedded in the bottom of the camera body, a miniature heat dissipation fan is provided at one end of the base and communicates with the internal cavity of the camera body, an air outlet is provided on the side wall of the base and communicates with the miniature heat dissipation fan, and an air inlet is provided on the side wall of the camera body. It also includes an adjustment assembly for adjusting the size of the air outlet and the air inlet. The adjustment assembly includes an air inlet hood plate set on the side wall of the camera body. The air inlet is opened on the air inlet hood plate. An arc-shaped adjustment plate is rotatably set on the inner side of the air inlet hood plate. The arc-shaped adjustment plate is provided with a through hole corresponding to the air inlet. A baffle plate is set on the inner side of the air outlet. A rectangular adjustment plate corresponding to the baffle plate is movably set on the inner side of the base. The rectangular adjustment plate and the baffle plate are provided with corresponding through holes. An air volume adjustment mechanism is provided on the base for driving the rectangular adjustment plate to move and the arc-shaped adjustment plate to rotate. The air inlet of the miniature cooling fan is equipped with a guide frame, in which a guide plate is rotatably mounted. The guide frame is equipped with an alternating swing mechanism for driving the guide plate to swing back and forth. Both the airflow adjustment mechanism and the alternating oscillation mechanism are thermally driven mechanisms, and their driving energy comes from the heat inside the camera body.

2. The handheld police-use color low-light night vision long-range evidence collection device according to claim 1, characterized in that: The air volume adjustment mechanism includes a second transverse frame movably mounted on the base, one end of a rectangular adjustment plate connected to the second transverse frame, a first rack at the end of the second transverse frame, a first gear corresponding to the first rack at the bottom of the arc-shaped adjustment plate, and a first temperature control drive element on one side of the second transverse frame.

3. The handheld police-use color low-light night vision long-range evidence collection device according to claim 2, characterized in that: The first temperature control drive element is a two-way shape memory alloy spring.

4. The handheld police-use color low-light night vision long-range evidence collection device according to claim 3, characterized in that: A handle is rotatably provided at the bottom of the base, and a second gear is provided on the handle. A first transverse frame is movably provided on the base above the handle. The side wall of the first transverse frame is evenly provided with gear teeth that mesh with the second gear. The first temperature control drive element is installed between the second transverse frame and the first transverse frame. A push rod for pushing the second transverse frame to move is provided at one end of the first transverse frame near the second transverse frame.

5. The handheld police-grade color low-light night vision long-range evidence collection device according to claim 4, characterized in that: The number of handles is two, and the two handles are set back to back. When the axis of the handle is parallel to the axis of the camera body, the air outlet and air inlet are closed. When the axis of the handle is perpendicular to the axis of the camera body, the air outlet and air inlet are open.

6. The handheld police-use color low-light night vision long-range evidence collection device according to claim 4, characterized in that: The first transverse frame has a guide rod corresponding to the first temperature control drive element at one end near the second transverse frame, and both the second transverse frame and the first temperature control drive element are movably sleeved on the guide rod.

7. The handheld police-use color low-light night vision long-range evidence collection device according to claim 1, characterized in that: The alternating swing mechanism includes cooling holes at both ends of the guide frame. A second rack is movably arranged on the inner side of the side wall of the guide frame. A third gear that meshes with the second rack is provided at the end of the guide plate. Traction plates corresponding to the cooling holes are respectively installed at both ends of the second rack. A second temperature control drive element is installed between the side wall of the traction plate and the inner wall of the cooling hole.

8. The handheld police-use color low-light night vision long-range evidence collection device according to claim 7, characterized in that: The second temperature control drive element is a single-pass shape memory alloy spring. When the single-pass shape memory alloy spring is heated to its phase transition temperature, it automatically contracts from an elongated state to a preset high-temperature shape. The configuration of the single-pass shape memory alloy springs at both ends is as follows: initially, one end of the single-pass shape memory alloy spring is in a contracted state and hidden in the cooling hole, while the other end of the single-pass shape memory alloy spring is in an extended state and exposed in the inner cavity of the camera body.

9. The handheld police-use color low-light night vision long-range evidence collection device according to claim 8, characterized in that: The air guide frame is equipped with a second air pipe that connects the cooling holes to the outside world and a first air pipe that connects the cooling holes to a miniature radiator fan.

10. The handheld police-use color low-light night vision long-range evidence collection device according to claim 9, characterized in that: Dustproof screens are installed in the second air pipe, air outlet, and air inlet.

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