A thermal imaging manual focusing mechanism based on hall sensor

Abstract

The utility model relates to a kind of thermal imaging manual focusing mechanism based on hall sensor, it includes lens assembly and electric propeller, lens assembly includes lens, lens seat, magnet assembly, manual focusing wheel and propelling support arranged sequentially, lens is set on the lens seat, manual focusing wheel is rotatably sleeved on the lens seat, propelling support is fixed to the rear end of the lens seat, magnet assembly is rotatably arranged between the rear end surface of the lens seat and propelling support, magnet assembly and the inner wall of the manual focusing wheel are in contact, propelling support is equipped with hall PCB board corresponding magnet assembly, the propelling support is fixed on electric propeller.The utility model design is reasonable and ingenious, magnet is rotated by focusing wheel, signal transmission is carried out to thermal imager by hall sensor when magnetic field changes, then it is converted into the pulse signal of control electric propeller, pulse signal controls the rotation step number of stepping motor, to realize the movement of detector before and after, reach the purpose of manual focusing.

Description

Technical Field

[0001] This application relates to thermal imagers, and more particularly to a manual focusing mechanism for thermal imaging based on a Hall sensor. Background Technology

[0002] In thermal imagers, current manual focusing methods all involve adjusting the lens elements of the lens assembly; the movement of these elements achieves focusing. This structure requires physical space for the lens assembly to move, making it difficult to design a smaller thermal imager. Furthermore, moving the entire lens assembly results in a relatively large lens mass, slow movement speed, and consequently, slow focusing speed.

[0003] The applicant uses a lens that remains stationary and adds a manual focus system. The manual focus signal is sent to the electric thruster, which moves the detector in the electric thruster to achieve focus. Utility Model Content

[0004] In view of at least one of the above technical problems, this application provides a thermal imaging manual focusing mechanism based on a Hall sensor.

[0005] An embodiment of the first aspect of this application provides a thermal imaging manual focusing mechanism based on a Hall sensor, which includes a lens assembly and an electric actuator. The lens assembly includes a lens, a lens mount, a magnet assembly, a manual focusing wheel, and an actuator bracket arranged sequentially. The lens is mounted on the lens mount, the manual focusing wheel is rotatably fitted onto the lens mount, the actuator bracket is fixed to the rear end of the lens mount, the magnet assembly is rotatably disposed between the rear end face of the lens mount and the actuator bracket, the magnet assembly is in contact with the inner wall of the manual focusing wheel, a Hall PCB board is provided on the actuator bracket corresponding to the magnet assembly, and the actuator bracket is fixed to the electric actuator.

[0006] As a further improvement of this utility model, a protruding edge is provided on the outer periphery of the front end of the lens mount, and the outer diameter of the protruding edge is larger than the outer diameter of the front end of the manual focusing wheel; the rear end of the manual focusing wheel is placed in the propulsion bracket.

[0007] As a further improvement of this utility model, the magnet assembly includes a magnet bracket, a magnet, a bearing, and a damping ring. The outer ring of the bearing is fixed to the rear end face of the lens mount. The front end of the magnet bracket is fixedly connected to the inner ring of the bearing. The magnet is fixed to the rear end of the magnet bracket. The damping ring is sleeved on the outer periphery of the magnet bracket and contacts the inner wall of the manual focusing wheel.

[0008] As a further improvement of this utility model, the Hall PCB board is disposed on the rear end face of the propulsion bracket, and the Hall magnetic sensor is provided on the Hall PCB board, which is disposed corresponding to the magnet.

[0009] As a further improvement of this utility model, the bottom surfaces of the lens mount, manual focusing wheel and propulsion bracket are provided with clearance holes corresponding to the lens.

[0010] As a further improvement of this utility model, the electric thruster includes a base with a cavity facing the lens assembly. A loading platform is provided in the cavity and can move back and forth. A detector is provided on the loading platform corresponding to the lens. The loading platform is driven to move back and forth by a power device.

[0011] As a further improvement of this utility model, an auxiliary guide rod is provided on one side of the cavity and a guide post is provided on the other side. The loading platform is provided with holes that cooperate with the auxiliary guide rod and the guide post, and the auxiliary guide rod and the guide post are respectively inserted into the holes.

[0012] As a further improvement of this utility model, the power device includes a stepper motor, the output end of which is connected to a lead screw, and a movable pusher driven by the lead screw to move back and forth is provided on the lead screw. The movable pusher is fixedly connected to the loading platform by a connecting rod.

[0013] As a further improvement of this utility model, it also includes a control board, which is disposed on the base. Two optical shutters are arranged on the control board, and a baffle is provided on the loading platform corresponding to the two optical shutters. The two optical shutters correspond to the upper and lower limits of the travel of the baffle, respectively.

[0014] As a further improvement of this utility model, a second guide rod is fixed on the housing of the stepper motor, and a through hole is provided on the movable pusher to cooperate with the second guide rod.

[0015] The loading platform is provided with a guide sleeve corresponding to the guide post, and the guide post passes through the guide sleeve.

[0016] The movable thruster is provided with a thread that mates with the lead screw.

[0017] The base has a top cover on its front end surface, and the top cover has a window corresponding to the cavity.

[0018] The top cover is fixed to the front end face of the base with screws.

[0019] The embodiments of this application have the following technical effects: The design of this utility model is reasonable and ingenious. By rotating the magnet through the focusing wheel, the magnetic field changes and the signal is transmitted to the thermal imager by the Hall sensor. It is then converted into a pulse signal to control the electric propeller. The pulse signal controls the stepper motor to rotate a certain number of steps, thereby realizing the forward and backward movement of the detector and achieving the purpose of manual focusing.

[0020] The present invention will be further described below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a three-dimensional structural schematic diagram of the present invention;

[0023] Figure 2 This is a three-dimensional structural schematic diagram of the present invention from another angle;

[0024] Figure 3 This is a schematic diagram of the structure of the magnet assembly in this utility model;

[0025] Figure 4 This is an exploded view of the present invention;

[0026] Figure 5 This is an exploded view of the present invention from another angle;

[0027] Figure 6 This is a schematic diagram of the electric propulsion device in this utility model;

[0028] Figure 7 This is an exploded view of the electric propulsion device in this utility model;

[0029] Figure 8 This is a schematic diagram of the loading platform and power unit in this utility model;

[0030] Figure 9 This is a schematic diagram of the cooperation between the light shutter and the baffle in this utility model. Detailed Implementation

[0031] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0032] In the description of this application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0033] In the description of this application, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0034] In the embodiments of this application, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this utility model can be understood according to the specific circumstances.

[0035] like Figures 1 to 9 As shown, an embodiment of this application provides a thermal imaging manual focusing mechanism based on a Hall sensor, which includes a lens assembly 1 and an electric actuator 2. The lens assembly 1 includes a lens 11, a lens mount 12, a magnet assembly 13, a manual focusing wheel 14, and a propulsion bracket 15 arranged sequentially. The lens 11 is disposed on the lens mount 12, the manual focusing wheel 14 is rotatably fitted onto the lens mount 12, the propulsion bracket 15 is fixed to the rear end of the lens mount 12, the magnet assembly 13 is rotatably disposed between the rear end face of the lens mount 12 and the propulsion bracket 15, and the magnet assembly 13 is in contact with the inner wall of the manual focusing wheel 14. A Hall PCB board 3 is provided on the propulsion bracket 15 corresponding to the magnet assembly 13, and the propulsion bracket 15 is fixed to the electric actuator 2.

[0036] The lens mount 12 has a protruding edge on its front outer periphery, the outer diameter of which is larger than the front outer diameter of the manual focusing wheel 14; the rear end of the manual focusing wheel 14 is placed in the push bracket 15. The manual focusing wheel 14 is restricted by the lens mount 12 and the push bracket 15 to not move back and forth, but can only rotate.

[0037] The magnet assembly 13 includes a magnet bracket 131, a magnet 132, a bearing 133, and a damping ring 134. The outer ring of the bearing 133 is fixed to the rear end face of the lens mount 12. The front end of the magnet bracket 131 is fixedly connected to the inner ring of the bearing 133. The magnet 132 is fixed to the rear end of the magnet bracket 131. The damping ring 134 is fitted onto the outer periphery of the magnet bracket 131 and contacts the inner wall of the manual focusing wheel 14. When the manual focusing wheel 14 is rotated, the interior of the manual focusing wheel 14 rubs against the damping ring 134, thereby driving the magnet bracket 131 to rotate, and consequently, the magnet 132 to rotate.

[0038] The lens 11 is mounted in the lens mount 12. A recess is provided on the rear end face of the lens mount 12 corresponding to the bearing 133, and the outer ring of the bearing 133 is fixed in this recess. The magnet 132 is fixed to the rear end of the magnet bracket 131, which can be achieved by adhesive application or other methods. The front end of the magnet bracket 131 is fixedly connected to the inner ring of the bearing 133, allowing the magnet 132 to rotate.

[0039] The propulsion bracket 15 has a clearance position corresponding to the magnet 132, so that the change in the magnetic field of the magnet 132 can be more easily detected by the Hall magnetic sensor.

[0040] The Hall PCB board 3 is disposed on the rear end face of the push support 15. The Hall PCB board 3 is provided with a Hall magnetic sensor 31, which is disposed corresponding to the magnet 132.

[0041] When the operator rotates the manual focusing wheel 14, the magnet 132 rotates accordingly. The Hall magnetic sensor 31 detects the change in the magnetic field between the N and S poles of the magnet 132. Based on the change in the magnetic field, the Hall sensor can output different signal values ​​to the control unit of the thermal imager. The control unit then converts the change in the signal value into a pulse signal to control the stepper motor of the electric thruster 2. The pulse signal controls the number of rotation steps of the stepper motor, thereby realizing the forward and backward movement of the detector.

[0042] When using it, you can first set the ratio of the displacement of the manual focusing wheel 14 to the electric propeller 2. For example, when the manual focusing wheel rotates one revolution, the detector in the electric propeller travels one round trip. This allows you to adjust the ratio to a suitable value according to the actual focusing requirements.

[0043] The bottom surfaces of the lens mount 12, the manual focus wheel 14, and the propulsion bracket 15 are provided with clearance holes corresponding to the lens 11. This will not interfere with the imaging of the lens 11 and the detector.

[0044] The electric propulsion unit 2 includes a base 21, on which a cavity 211 is provided facing the lens assembly 11. A loading platform 22 is movably mounted in the cavity 211. A detector 23 is mounted on the loading platform 22 corresponding to the lens 11. The loading platform 22 is driven to move back and forth by a power device. The loading platform 22 drives the detector 23 to move back and forth. When the focal plane of the detector 23 moves to the focal point, it achieves focusing, thereby realizing the purpose of automatic focusing by moving the detector 23.

[0045] The cavity 211 has an auxiliary guide rod 24 on one side and a guide post 25 on the other side. The loading platform 22 has holes that mate with the auxiliary guide rod 24 and the guide post 25, and the auxiliary guide rod 24 and the guide post 25 are respectively inserted into the holes. Due to the setting of the auxiliary guide rod 24 and the guide post 25, the loading platform 22 moves smoothly without shaking or vibration, and the imaging quality is stable.

[0046] The power unit includes a stepper motor 26, the output end of which is connected to a lead screw 27. A movable thruster 28, driven to move back and forth by the lead screw 27, is mounted on the lead screw 27. A connecting rod 29 is fixedly connected to the movable thruster 28 and the loading platform 22. The connecting rod 29 connects the movable thruster 28 to the loading platform 22, allowing the loading platform 22 to move along with the movable thruster 28. In other embodiments, power may be provided by other power units, and other connection methods may be used to drive the loading platform 22.

[0047] It also includes a control board 210, which is mounted on the base 21. Two shutters 212 are arranged on the control board 210. A baffle 213 is provided on the loading platform 22 corresponding to the two shutters 212. The two shutters 212 correspond to the upper and lower limits of the travel of the baffle 213, respectively. The baffle 213 moves with the loading platform 22. When the baffle 213 is located at the upper or lower shutter 212, it blocks the signal of the shutter 212, allowing the thermal imager to determine the upper or lower limit position of the loading platform 22.

[0048] A second guide rod 261 is fixed to the housing of the stepper motor 26, and the movable pusher 28 has a through hole that mates with the second guide rod 261. Due to the second guide rod 261 and the fact that the stepper motor 26 is fixed to the base 21, the movable pusher 28 will move forward or backward when the stepper motor 26 rotates forward or backward.

[0049] The loading platform 22 is provided with a guide sleeve corresponding to the guide post 25, and the guide post 25 passes through the guide sleeve. Through the cooperation of the guide sleeve and the guide post 25, the movement of the loading platform 22 is more stable and does not shake.

[0050] The movable thruster 28 is provided with a thread that mates with the lead screw 27.

[0051] The base 21 has a top cover 214 on its front end surface, and the top cover 214 has a window corresponding to the cavity 211.

[0052] The top cover 214 is fixed to the front end face of the base 21 by screws.

[0053] This utility model is reasonably and ingeniously designed. By rotating the magnet 132 through the focusing wheel, the magnetic field changes and the signal is transmitted to the thermal imager by the Hall sensor. It is then converted into a pulse signal to control the electric propeller 2. The pulse signal controls the stepper motor 26 to rotate a certain number of steps, thereby realizing the forward and backward movement of the detector 23 and achieving the purpose of manual focusing.

[0054] The above description is merely a preferred embodiment of this application and does not constitute any limitation on this application. Any person skilled in the art can make many possible variations and modifications to the technical solution of this application, or modify it into equivalent embodiments, without departing from the scope of the technical solution of this application. Therefore, all equivalent changes made based on the shape, structure, and principle of this application without departing from the content of the technical solution of this application should be covered within the protection scope of this application.

Claims

1. A manual focusing mechanism for thermal imaging based on a Hall sensor, comprising a lens assembly and an electric actuator, characterized in that, The lens assembly includes a lens, a lens mount, a magnet assembly, a manual focus wheel, and a propulsion bracket arranged sequentially. The lens is mounted on the lens mount, the manual focus wheel is rotatably fitted onto the lens mount, the propulsion bracket is fixed to the rear end of the lens mount, the magnet assembly is rotatably disposed between the rear end face of the lens mount and the propulsion bracket, the magnet assembly is in contact with the inner wall of the manual focus wheel, and a Hall effect PCB board is provided on the propulsion bracket corresponding to the magnet assembly. The propulsion bracket is fixed to the electric propeller.

2. The thermal imaging manual focusing mechanism based on a Hall sensor according to claim 1, characterized in that, The lens mount has a raised edge on its front outer periphery, and the outer diameter of the raised edge is larger than the front outer diameter of the manual focusing wheel; the rear end of the manual focusing wheel is placed in the propulsion bracket.

3. The thermal imaging manual focusing mechanism based on a Hall sensor according to claim 2, characterized in that, The magnet assembly includes a magnet bracket, a magnet, a bearing, and a damping ring. The outer ring of the bearing is fixed to the rear end face of the lens mount. The front end of the magnet bracket is fixedly connected to the inner ring of the bearing. The magnet is fixed to the rear end of the magnet bracket. The damping ring is fitted on the outer periphery of the magnet bracket and contacts the inner wall of the manual focusing wheel.

4. The thermal imaging manual focusing mechanism based on a Hall sensor according to claim 3, characterized in that, The Hall PCB board is disposed on the rear end face of the propulsion bracket, and a Hall magnetic sensor is provided on the Hall PCB board, which is disposed corresponding to the magnet.

5. The thermal imaging manual focusing mechanism based on a Hall sensor according to claim 1, characterized in that, The lens mount, manual focus wheel, and propulsion bracket have clearance holes on their bottom surfaces corresponding to the lens.

6. The thermal imaging manual focusing mechanism based on a Hall sensor according to any one of claims 1 to 5, characterized in that, The electric thruster includes a base with a cavity facing the lens assembly. A loading platform is movably mounted in the cavity, and a detector is mounted on the loading platform corresponding to the lens. The loading platform is driven to move back and forth by a power unit.

7. The thermal imaging manual focusing mechanism based on a Hall sensor according to claim 6, characterized in that, An auxiliary guide rod is provided on one side of the cavity, and a guide post is provided on the other side. The loading platform is provided with holes that cooperate with the auxiliary guide rod and the guide post, and the auxiliary guide rod and the guide post are respectively inserted into the holes.

8. The thermal imaging manual focusing mechanism based on a Hall sensor according to claim 7, characterized in that, The power unit includes a stepper motor, the output end of which is connected to a lead screw. The lead screw is equipped with a movable thruster that is driven to move back and forth. The movable thruster is fixedly connected to the loading platform by a connecting rod.

9. The thermal imaging manual focusing mechanism based on a Hall sensor according to claim 8, characterized in that, It also includes a control board, which is mounted on the base. Two shutters are arranged on the control board, and baffles are provided on the loading platform corresponding to the two shutters. The two shutters correspond to the upper and lower limits of the travel of the baffles, respectively.

10. The thermal imaging manual focusing mechanism based on a Hall sensor according to claim 9, characterized in that, A second guide rod is fixed on the housing of the stepper motor, and a through hole is provided on the movable pusher to cooperate with the second guide rod.

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