A focusing mechanism and infrared imaging device

Abstract

The present invention relates to the technical field of optoelectronic testing equipment, and discloses a focusing mechanism and an infrared imaging device. The focusing mechanism comprises a fixed frame, a movable frame, a guide assembly, a driving screw and a half nut. The movable frame is located above the fixed frame. One side of the movable frame is connected to the fixed frame through a guide assembly, and the guide assembly is used to limit the movement of the movable frame along a first direction. The axis of the driving screw extends along the first direction. The half nut is movably connected to the other side of the movable frame, and the half nut can move a limited distance along the first direction, the second direction and the third direction relative to the movable frame, and maintain a transmission connection with the driving screw, and the first direction, the second direction and the third direction are perpendicular to each other. Compared with the prior art, in the focusing process of the present invention, the half nut can move a limited distance along the first direction, the second direction and the third direction, and maintain a transmission connection with the driving screw, thereby avoiding the problem of jamming during the focusing process.

Description

Technical Field

[0001] The invention relates to the technical field of photoelectric testing equipment, and in particular to a focusing mechanism and infrared imaging equipment. Background Art

[0002] Infrared imaging equipment mainly converts the invisible infrared energy emitted by an object into a visible thermal image through the cooperation of an infrared detector and a lens group. The distance between the infrared detector and the lens group is mainly adjusted by the focusing mechanism, thereby changing the distance between the optical center of the lens and the focal plane to obtain a clear image of the object.

[0003] like Figure 1 As shown, the focusing mechanism of the existing infrared imaging device mainly includes a fixed frame 1' and a mobile frame 2'. Among them, the infrared detector is installed on the mobile frame 2', the lens group is installed on the fixed frame 1', one end of the mobile frame 2' is connected to a slider 4', the slider 4' is slidably plugged on the slide rail 3', the slide rail 3' is fixed on the fixed frame 1' along a first direction, and the mobile frame 2' basically cannot swing relative to the fixed frame 1', and can only move up and down along the slide rail 3' relative to the fixed frame 1', so as to adjust the distance between the mobile frame 2' and the fixed frame 1'. In addition, it is also provided with a stepping motor 6' and a driving screw 5' for driving the mobile frame 2' to move. The stepper motor 6' is fixedly mounted on the fixed frame 1', and the end of the driving screw 5' not connected to the stepper motor 6' is rotatably mounted at the mounting position 7' ​​on the fixed frame 1', and the axis of the driving screw 5' extends along the first direction to maintain parallelism with the slide rail 3'. A threaded hole is provided on the other side of the mobile frame 2', and the driving screw 5' is inserted into the threaded hole. The driving screw 5' can drive the mobile frame 2' to approach or move away from the fixed frame 1' by rotating.

[0004] However, in the process of machining the threaded hole of the moving frame 2', machining errors are inevitable, and there is also a certain matching tolerance between the threaded hole and the driving screw 5'. When the driving screw 5' drives the moving frame 2' to move, the driving screw 5' is offset or the driving screw 5' is no longer parallel to the slide rail 3', which easily leads to the problem that the driving screw 5' and the threaded hole are stuck to each other during the actual focusing movement of the moving frame 2'.

[0005] In view of the above problems, it is urgently necessary to provide a focusing mechanism and an infrared imaging device that can avoid the problem of jamming during the focusing process. Summary of the invention

[0006] An object of the present invention is to provide a focusing mechanism that can avoid the problem of jamming during the focusing process.

[0007] To achieve this object, the present invention adopts the following technical solutions:

[0008] A focusing mechanism, comprising:

[0009] Fixed frame;

[0010] A mobile frame, located above the fixed frame;

[0011] A guide assembly, one side of the mobile frame is connected to the fixed frame through the guide assembly, and the guide assembly is used to limit the mobile frame to move along a first direction;

[0012] a driving screw, the axis of which extends along the first direction;

[0013] A half nut is movably connected to the other side of the movable frame, and the half nut can move a limited distance relative to the movable frame along the second direction, the third direction and the first direction, and maintain a transmission connection with the driving screw, and the first direction, the second direction and the third direction are perpendicular to each other.

[0014] Optionally, a accommodating cavity is provided on the movable frame, and the half nut is arranged in the accommodating cavity.

[0015] Optionally, the focusing mechanism further includes:

[0016] The first elastic member is arranged along the second direction, and one end of the first elastic member abuts against the half nut, and the other end abuts against the inner wall of the accommodating cavity, so that the half nut elastically abuts against the driving screw.

[0017] Optionally, the first elastic member is a compression spring, the half nut is provided with a limiting protrusion extending along the second direction, and one end of the compression spring abutting against the half nut is sleeved on the limiting protrusion.

[0018] Optionally, the focusing mechanism further includes:

[0019] The guide pin is slidably arranged on the half nut along the third direction, and the two ends of the guide pin extend out of the half nut and movably abut against the inner wall of the accommodating cavity.

[0020] Optionally, the focusing mechanism further includes:

[0021] The second elastic member is arranged along the first direction, and one end of the second elastic member abuts against the half nut, and the other end abuts against the inner wall of the accommodating cavity, so that the half nut elastically abuts against the inner wall of the accommodating cavity.

[0022] Optionally, the mobile frame comprises:

[0023] Connecting part;

[0024] A half nut carrier plate is detachably connected to the connecting portion, and the half nut carrier plate and the connecting portion cooperate to form the accommodating cavity.

[0025] Optionally, the connecting portion is connected to the half nut carrier plate via screws.

[0026] Optionally, the focusing mechanism further includes:

[0027] The stepper motor is arranged on the fixing frame, and the output end of the stepper motor is drivingly connected to the driving lead screw.

[0028] Another object of the present invention is to provide an infrared imaging device, in which a focusing mechanism can avoid the problem of getting stuck during the focusing process.

[0029] To achieve this object, the present invention adopts the following technical solutions:

[0030] An infrared imaging device comprises the focusing mechanism as described above.

[0031] The beneficial effects of the present invention are:

[0032] The focusing mechanism of the present invention has a movable frame located above the fixed frame, and one side of the movable frame is connected to the fixed frame via a guide assembly, and the guide assembly is used to limit the movement of the movable frame along a first direction. The axis of the driving screw extends along the first direction. The half nut is movably connected to the other side of the movable frame, and the half nut can move a limited distance along the first direction, the second direction and the third direction relative to the movable frame, and maintain a transmission connection with the driving screw. Compared with the design structure in the prior art in which the driving screw is directly threadedly connected to the threaded hole opened on the movable frame, during the focusing process of the focusing mechanism of the present invention, the half nut can move a limited distance along the first direction, the second direction and the third direction, and maintain a transmission connection with the driving screw, thereby avoiding the problem of jamming during the focusing process. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 is a cross-sectional view of a focusing mechanism in the prior art;

[0034] Figure 2 is a cross-sectional view of the focusing mechanism provided by the present invention;

[0035] Figure 3 is a structural view of the focusing mechanism provided by the present invention;

[0036] Figure 4 It is one of the partial cross-sectional views of the position of the half nut and the driving screw provided by the present invention;

[0037] Figure 5 This is a partial structural view of the half nut provided by the present invention after the driving screw is hidden;

[0038] Figure 6 This is the second partial cross-sectional view of the position of the half nut and the driving screw provided by the present invention.

[0039] In the figure:

[0040] Z-first direction; X-second direction; Y-third direction;

[0041] 1'-fixed frame; 2'-movable frame; 3'-slide rail; 4'-slider; 5'-driving screw; 6'-stepping motor; 7'-installation position;

[0042] 1-fixed frame; 2-movable frame; 21-connecting part; 22-half nut carrier plate; 3-guide assembly; 4-driving screw; 5-half nut; 51-limiting protrusion; 6-first elastic member; 7-guide pin; 8-second elastic member; 9-screw; 10-stepping motor. DETAILED DESCRIPTION

[0043] In order to make the technical problem solved by the present invention, the technical solution adopted and the technical effect achieved more clearly, the technical solution of the present invention is further explained below with reference to the accompanying drawings and through specific implementation methods.

[0044] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0045] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0046] In the description of this embodiment, the terms "upper", "lower", "left", "right" and other directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplification of operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operate in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0047] like Figure 2-4 As shown, a focusing mechanism provided in this embodiment is mainly installed in optoelectronic equipment such as infrared imaging equipment. The main function of the focusing mechanism in the infrared imaging equipment is to adjust the distance between the infrared detector and the lens group to realize the focusing setting of the infrared thermal imaging device. In the figure, the Z direction is the first direction, the X direction is the second direction, and the Y direction is the third direction. The first direction, the second direction and the third direction are perpendicular to each other. The focusing mechanism mainly includes a fixed frame 1, a mobile frame 2, a guide assembly 3, a drive screw 4 and a half nut 5. Among them, a lens group is installed on the fixed frame 1, the mobile frame 2 is located above the fixed frame 1, the infrared detector is installed on the mobile frame 2, and one side of the mobile frame 2 is connected to the fixed frame 1 through the guide assembly 3, and the guide assembly 3 is used to limit the mobile frame 2 to move in the first direction. The other side of the mobile frame 2 is movably connected with a half nut 5, and the half nut 5 is connected to the drive screw 4 in a transmission connection. The axis of the drive screw 4 extends along the first direction, and the drive screw 4 is connected to the output end of the stepper motor 10 in a transmission connection. The stepper motor 10 is fixedly installed on the fixed frame 1. Driven by the stepper motor 10, the driving screw 4 can drive the mobile frame 2 to move along the first direction to achieve the purpose of adjusting the distance between the fixed frame 1 and the mobile frame 2, and the half nut 5 in this embodiment can move a limited distance relative to the mobile frame 2 along the first direction, the second direction and the third direction, and maintain a transmission connection with the driving screw 4.

[0048] In the prior art, the driving screw 4 is directly threadedly connected to the threaded hole opened on the moving frame 2. Due to the assembly design error, the focusing mechanism is prone to jamming during the focusing process. The focusing mechanism of this embodiment adopts a design structure in which the half nut 5 is connected to the driving screw 4 in a transmission manner, and the half nut 5 is floatingly arranged on the moving frame 2, and the driving screw 4 is arranged opposite and parallel to the guide assembly 3. During the focusing process, the half nut 5 can move a limited distance along the first direction, the second direction and the third direction, and maintain a transmission connection with the driving screw 4. Such a design enables the half nut 5 to move appropriately to ensure the normal cooperation between the thread of the half nut 5 and the thread of the driving screw 4 when the driving screw 4 is offset during the focusing process, and finally avoids the jamming problem and ensures the normal operation of the focusing mechanism. Therefore, the focusing mechanism is not easy to be damaged during actual application, and the service life is improved. At the same time, from the perspective of production difficulty and efficiency, since the half nut 5 can move relative to the movable frame 2 along the first direction, the second direction and the third direction during the focusing process to maintain normal cooperation with the driving screw 4, compared with the design structure of the prior art in which a threaded hole is directly opened on the movable frame 2, the focusing mechanism of this embodiment has low assembly requirements for processing and production, and it is easier to ensure the assembly yield, thereby effectively improving production efficiency.

[0049] Specifically, if Figure 3As shown, in this embodiment, the guide assembly 3 includes a guide rail and a slider, the guide rail is fixedly installed on one side of the fixed frame 1 along the first direction, the slider is slidably plugged on the guide rail, and one side of the mobile frame 2 is fixedly connected to the slider. In other embodiments, the guide assembly 3 can also be a guide column, the guide column is a cylindrical column, the guide column is fixedly installed on the fixed frame 1 along the first direction, and a socket matching the shape and size of the guide column is opened on one side of the mobile frame 2, the guide column passes through the socket, so that the mobile assembly can slide along the axial direction of the guide column, which can also play a role in limiting the movement of the mobile frame 2 along the first direction.

[0050] In order to realize the movable connection of the half nut 5 on the mobile frame 2, as shown in FIG. Figure 4-5 As shown, a accommodating cavity is provided on the movable frame 2, and a half nut 5 is provided in the accommodating cavity. The half nut 5 can move a limited distance in the accommodating cavity along the first direction, the second direction and the third direction. Among them, the movable frame 2 includes a connecting portion 21 and a half nut carrier plate 22. The half nut carrier plate 22 is detachably connected to the connecting portion 21, and the half nut carrier plate 22 and the connecting portion 21 cooperate to form an accommodating cavity. Specifically, the connecting portion 21 is connected to the half nut carrier plate 22 by screws 9. This structural design has low cost and is convenient for installation and disassembly. More specifically, as Figure 5-6 As shown, in this embodiment, a C-shaped flange is convexly provided at the upper end of the side of the connecting portion 21 close to the half nut 5, and a receiving groove for receiving the half nut 5 is provided on the half nut carrier 22. The receiving groove is a square groove with the same shape as the half nut 5, and the size of the half nut 5 is smaller than the square groove. The half nut 5 can be movably arranged in the receiving groove, and a connecting plate is convexly provided on one end of the half nut carrier 22 close to the connecting portion 21. The connecting plate of the half nut carrier 22 is bolted to the connecting portion 21 of the mobile frame 2 by screws 9. At this time, the C-shaped flange of the connecting portion 21 is located above the half nut 5, and then cooperates with the receiving groove of the half nut carrier 22 to form a receiving cavity, and finally realizes that the half nut 5 can be movably arranged on the mobile frame 2.

[0051] In order to achieve that the half nut 5 can be kept against the driving screw 4 along the second direction, as shown in FIG. Figure 6 As shown, the focusing mechanism in this embodiment further includes a first elastic member 6, which is a compression spring. The first elastic member 6 is arranged in the accommodating cavity along the second direction, and one end of the first elastic member 6 abuts against the half nut 5, and the other end of the first elastic member 6 abuts against the inner wall of the accommodating cavity. The first elastic member 6 has an elastic force after being compressed, and can push the half nut 5 against the driving screw 4 along the second direction, so that the half nut 5 elastically abuts against the driving screw 4.

[0052] Furthermore, in order to prevent the compression spring from being deflected during long-term use, Figure 6As shown, a limiting protrusion 51 extending in the second direction is provided on the half nut 5, and one end of the compression spring abutting against the half nut 5 is sleeved on the limiting protrusion 51, and the limiting protrusion 51 plays a role in fixing the position of the compression spring to prevent it from being offset. Among them, the limiting protrusion 51 is located in the middle position of the side of the half nut 5 away from the driving screw 4, so that the axis of the compression spring can pass through the center of the circle of the driving screw 4, and the compression spring can push the half nut 5 against the driving screw 4 in the direction facing the driving screw 4, ensuring that the thread fit between the driving screw 4 and the half nut 5 is more reasonable.

[0053] In order to enable the half nut 5 to move a limited distance along the third direction. Figure 6 As shown, the focusing mechanism also includes a guide pin 7. The guide pin 7 is slidably inserted into the half nut 5 along the third direction, and both ends of the guide pin 7 extend out of the half nut 5 and movably abut against the inner wall of the accommodating cavity. Since the half nut 5 can slide back and forth along the third direction on the guide pin 7, when the driving screw 4 deviates to a certain extent along the third direction, the half nut 5 can move a certain distance along the third direction accordingly, and finally the half nut 5 is always facing the driving screw 4, ensuring that the thread fit between the driving screw 4 and the half nut 5 is more reasonable.

[0054] In addition, in other embodiments, the guide pin 7 may not be provided. Since the width of the half nut 5 along the third direction is smaller than the width of the accommodating chamber along the third direction, the half nut 5 may also move along the third direction in the accommodating chamber. However, when the driving screw 4 rotates, since the half nut 5 is not provided with the guide pin 7, the half nut 5 at this time will rotate in the accommodating chamber under the action of the driving screw 4, thereby reducing the transmission drive accuracy of the driving screw 4 and the half nut 5, and affecting the displacement accuracy of the moving frame 2. Therefore, in this embodiment, the guide pin 7 is slidably provided on the half nut 5 along the third direction, and the two ends of the guide pin 7 extend out of the half nut 5 and moveably abut against the inner wall of the accommodating chamber. On the one hand, it ensures that the half nut 5 can move a limited distance along the third direction, and on the other hand, it also makes the half nut 5 unable to rotate, thereby ensuring the accuracy of the driving screw 4 adjusting the movement of the moving plate 2 and ensuring a good use effect.

[0055] In addition, in this embodiment, the C-shaped flange of the connecting portion 21 is located above the half nut 5, and then cooperates with the receiving groove of the half nut carrier 22 to form a receiving cavity. The thickness of the half nut 5 along the first direction is less than the height of the receiving cavity along the first direction, so that the half nut 5 can move a small distance in the receiving cavity along the first direction. In this embodiment, the distance that the half nut 5 can move in the receiving cavity along the first direction is 0.5 mm. The half nut 5 is pushed against the drive screw 4 under the elastic force of the first elastic member 6. When the thread of the half nut 5 does not match the thread of the drive screw 4 reasonably, the half nut 5 can move appropriately along the first direction, so that the thread of the half nut 5 can match the thread of the drive screw 4 more reasonably, and no jamming will occur.

[0056] Furthermore, in order to ensure that the half nut 5 can be stably arranged in the accommodating cavity, the half nut 5 will only move to avoid jamming when the force acting on the half nut 5 is relatively large, so as to ensure the working accuracy of the focusing mechanism. Figure 4-5 As shown, the focusing mechanism of this embodiment also includes a second elastic member 8. The second elastic member 8 is arranged in the accommodating chamber along the first direction, and one end of the second elastic member 8 abuts against the half nut 5, and the other end of the second elastic member 8 abuts against the inner wall of the accommodating chamber, so that the half nut 5 elastically abuts against the inner wall of the accommodating chamber. In this embodiment, the second elastic member 8 is a disc spring, and the disc spring is located directly below the half nut 5. Under the elastic force of the disc spring, the half nut 5 is pushed against the lower side wall of the C-shaped flange of the connecting part 21 along the first direction, so that the half nut 5 is no longer easy to move along the first direction. Only when the half nut 5 and the driving screw 4 are prone to getting stuck, the half nut 5 will move when the force acting on it is relatively large to avoid the problem of getting stuck, so that the half nut 5 can be relatively stably arranged in the accommodating chamber, thereby ensuring the working accuracy of the focusing mechanism.

[0057] It can be seen that the half nut 5 of the focusing mechanism in this embodiment is accommodated in the accommodating chamber, and the first elastic member 6 is used to elastically press the half nut 5 against the driving screw 4 in the second direction. In actual work, the half nut 5 can move in the second direction in coordination with the specific position of the driving screw 4; at the same time, the guide pin 7 is used to enable the half nut 5 to move in the third direction without rotating; and the second elastic member 8 further limits the position of the half nut 5 in the first direction. Only when the half nut 5 and the driving screw 4 are prone to get stuck, the half nut 5 will move when the force acting on it is relatively large, and finally the half nut 5 can always be pressed against the driving screw 4, and the thread of the half nut 5 and the thread of the driving screw 4 can maintain a good matching relationship, and on the one hand, the transmission accuracy of the driving screw 4 is guaranteed, and on the other hand, the problem that the focusing mechanism is prone to get stuck in the prior art is solved, and the structure of the half nut 5 is simple, easy to process, and low in design cost.

[0058] In addition, the present embodiment also provides an infrared imaging device, which includes a focusing mechanism provided in the present embodiment. During the focusing process, the half nut 5 can move a limited distance along the second direction, the third direction and the first direction, and maintain a transmission connection with the driving screw 4. As a result, when the driving screw 4 is displaced, the half nut 5 can be appropriately displaced to ensure the normal fit between the thread of the half nut 5 and the thread of the driving screw 4, ultimately avoiding the problem of jamming during the focusing process and ensuring the normal use of the focusing mechanism.

[0059] The above contents are only preferred embodiments of the present invention. For ordinary technicians in this field, according to the concept of the present invention, there will be changes in the specific implementation methods and application scopes. The content of this specification should not be understood as limiting the present invention.

Claims

1. A focusing mechanism, characterized in that: include: Fixed frame (1); A movable frame (2) located above the fixed frame (1); A guide assembly (3), one side of the movable frame (2) is connected to the fixed frame (1) via the guide assembly (3), and the guide assembly (3) is used to limit the movable frame (2) to move along a first direction; A driving screw (4), the axis of which extends along the first direction; a half nut (5) movably connected to the other side of the movable frame (2), and the half nut (5) can move a limited distance relative to the movable frame (2) along a second direction, a third direction and the first direction, and maintain a transmission connection with the driving screw (4), the first direction, the second direction and the third direction being perpendicular to each other; The movable frame (2) is provided with a receiving cavity, and the half nut (5) is arranged in the receiving cavity; The mobile frame (2) comprises: Connecting portion (21); a half nut carrier plate (22) which is detachably connected to the connecting portion (21), wherein the half nut carrier plate (22) and the connecting portion (21) cooperate to form the accommodating cavity; the connecting portion (21) and the half nut carrier plate (22) are connected via screws (9); A C-shaped flange is provided at the upper end of the connecting portion (21) on one side close to the half nut (5); a receiving groove for receiving the half nut (5) is provided on the half nut carrier (22); the receiving groove is a square groove with the same shape as the half nut (5); the size of the half nut (5) is smaller than the square groove; the half nut (5) can be movably arranged in the receiving groove; a connecting plate is provided at one end of the half nut carrier (22) close to the connecting portion (21); the connecting plate of the half nut carrier (22) is bolted to the connecting portion (21) of the movable frame (2) via the screw (9); the C-shaped flange of the connecting portion (21) is located above the half nut (5), and then cooperates with the receiving groove of the half nut carrier (22) to form the receiving cavity, so that the half nut (5) can be movably arranged on the movable frame (2).

2. The focusing mechanism according to claim 1, characterized in that: The focusing mechanism also includes: A first elastic member (6) is arranged along the second direction, and one end of the first elastic member (6) abuts against the half nut (5) and the other end abuts against the inner wall of the accommodating cavity, so that the half nut (5) elastically abuts against the driving screw (4).

3. The focusing mechanism according to claim 2, characterized in that: The first elastic member (6) is a compression spring, the half nut (5) is provided with a limiting protrusion (51) extending along the second direction, and one end of the compression spring abutting against the half nut (5) is sleeved on the limiting protrusion (51).

4. The focusing mechanism according to claim 1, characterized in that: The focusing mechanism also includes: The guide pin (7) is slidably disposed on the half nut (5) along the third direction, and both ends of the guide pin (7) extend out of the half nut (5) and movably abut against the inner wall of the accommodating cavity.

5. The focusing mechanism according to claim 1, characterized in that: The focusing mechanism also includes: The second elastic member (8) is arranged along the first direction, and one end of the second elastic member (8) abuts against the half nut (5) and the other end abuts against the inner wall of the accommodating cavity, so that the half nut (5) elastically abuts against the inner wall of the accommodating cavity.

6. The focusing mechanism according to claim 1, characterized in that: The focusing mechanism also includes: A stepper motor (10) is arranged on the fixing frame (1), and an output end of the stepper motor (10) is drivingly connected to the driving lead screw (4).

7. An infrared imaging device, characterized in that: It comprises a focusing mechanism as described in any one of claims 1-6.

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