Focusing structure

Abstract

The invention discloses a focusing structure, and relates to the technical field of optics, the focusing structure comprises a mounting bracket, a driving cylinder, a lens cone and an elastic structure, the driving cylinder is arranged on the mounting bracket along the front-back direction and can rotate along the axis of the front-back direction, at least one driving chute is formed in the peripheral wall of the driving cylinder, the driving chute extends along the front-back direction, and the driving cylinder is arranged on the mounting bracket. The front end of the driving chute and the rear end of the driving chute are staggered along the circumferential direction of the lens cone; the lens barrel is movably installed in the fixing barrel in the front-back direction, at least one connecting piece is fixed to the outer circumferential wall of the lens barrel, the connecting piece is installed in the driving inclined groove in a sliding mode, and when the driving barrel rotates relative to the lens barrel, the driving inclined groove drives the connecting piece to drive the lens barrel to move front and back; the elastic structure is arranged between the rear end of the lens barrel and the mounting bracket and is used for providing elastic force when the lens barrel moves forwards; through the arrangement, the focusing structure capable of realizing high-precision and high-stability focusing is provided.

Description

Technical Field

[0001] The invention relates to the field of optical technology, and in particular to a focusing structure. Background Art

[0002] Traditional focusing structures usually rely on sliding friction to adjust the lens position, which is prone to wear and tear, affecting the life and accuracy of the focusing system. In addition, traditional structures may have gaps between moving parts, which can cause errors in the focusing process and reduce image quality. Therefore, it is of great practical significance to develop a focusing structure that can provide higher stability and accuracy. Summary of the invention

[0003] The main purpose of the present invention is to provide a focusing structure, aiming to provide a focusing structure that can achieve high-precision and high-stability focusing.

[0004] To achieve the above object, the focusing structure proposed in the present invention includes:

[0005] Mounting bracket;

[0006] A driving cylinder is arranged on the mounting bracket in the front-to-back direction and can rotate along the axis in the front-to-back direction, and a peripheral wall of the driving cylinder is formed with at least one driving inclined groove, the driving inclined groove extends in the front-to-back direction, and a front end of the driving inclined groove and a rear end of the driving inclined groove are staggered along the circumference of the lens barrel;

[0007] A lens barrel is movably mounted in the fixed barrel in a front-to-back direction, at least one connecting member is fixed to the outer peripheral wall of the lens barrel, and the connecting member is slidably mounted in the driving inclined groove. When the driving barrel rotates relative to the lens barrel, the driving inclined groove drives the connecting member to drive the lens barrel to move forward and backward; and

[0008] The elastic structure is arranged between the rear end of the lens barrel and the mounting bracket, and is used for providing a forward elastic force when the lens barrel moves forward and backward.

[0009] In one embodiment, the peripheral wall of the lens barrel is provided with a groove corresponding to the driving inclined groove;

[0010] The connecting piece comprises:

[0011] A first bearing is disposed in the driving chute;

[0012] A pin passes through the inner hole of the first bearing to be fixed in the groove of the lens barrel.

[0013] In one embodiment, the focusing structure further includes a connecting plate and a cover plate, wherein the connecting plate is fixedly connected to the mounting bracket and is arranged corresponding to the rear end surface of the driving cylinder; the cover plate is arranged to cover the mounting bracket, and the cover plate includes a plurality of through holes for accommodating and making way for the driving cylinder;

[0014] The elastic structure comprises:

[0015] At least one guide shaft is arranged between the cover plate and the connecting plate along the front-rear direction, and the guide shaft passes through the rear end surface of the lens barrel;

[0016] At least one spring is sleeved on the guide shaft, and two ends of the spring are respectively in contact with the front end surface of the connecting plate and the rear end surface of the lens barrel, so as to provide elastic force when the lens barrel moves forward and backward.

[0017] In one embodiment, the focusing structure further comprises a driving motor disposed on the mounting bracket, the driving motor comprises an output shaft extending in a front-to-rear direction, and a first gear is disposed on the output shaft;

[0018] The outer peripheral wall of the driving cylinder is provided with an annular rack meshing with the first gear.

[0019] In one embodiment, the focusing structure includes an encoder disposed on the mounting bracket to detect the rotation angle of the driving cylinder, and the encoder includes:

[0020] An encoder body, the encoder body being fixedly connected to the mounting bracket;

[0021] An encoder shaft extending in the front-rear direction, the encoder shaft being provided with a second gear meshing with the annular rack;

[0022] A magnetic grid, wherein the magnetic grid is arranged on an end of the encoder shaft away from the second gear, and the encoder body covers the magnetic grid;

[0023] A torsion spring is sleeved on the outside of the encoder shaft, one end of the torsion spring in the front-to-back direction is in contact with the mounting bracket, and at least a part of the other end is arranged in the inner hole of the second gear, so as to apply a pre-tightening force along the circumference of the encoder shaft to the second gear when the annular rack drives the second gear to rotate, and to apply a pre-tightening force along the direction away from the encoder body to the encoder shaft.

[0024] In one embodiment, the focusing structure further comprises a fixed cylinder, which is arranged between the driving cylinder and the lens barrel in the front-to-back direction, and the peripheral wall of the fixed cylinder is formed with at least one driving straight groove corresponding to the driving oblique groove, and the driving straight groove extends in the front-to-back direction;

[0025] The connecting member passes through the driving straight groove to slide with the driving oblique groove. When the driving cylinder rotates relative to the lens barrel, the connecting member slides along the driving straight groove.

[0026] In one embodiment, a second bearing is disposed in the driving straight groove, and the connecting member at least partially passes through an inner hole of the second bearing and extends into the driving inclined groove.

[0027] In one embodiment, a first annular groove is formed at the front end of the fixing cylinder and at the side opposite to the driving cylinder, respectively, for accommodating the ball; and / or,

[0028] The focusing structure also includes a connecting plate, which is fixedly connected to the mounting bracket and arranged corresponding to the rear end face of the driving cylinder. The side surfaces of the connecting plate opposite to the rear end face of the driving cylinder are respectively formed with second annular grooves for accommodating balls.

[0029] In one embodiment, a threaded hole is provided on the rear end surface of the fixing tube;

[0030] The focusing structure comprises a connecting screw, comprising a screw head, wherein the connecting screw passes through the threaded hole and the screw head abuts against the mounting bracket;

[0031] A first gasket is arranged between the screw head and the rear end surface of the fixing tube.

[0032] In one embodiment, the peripheral wall of the lens barrel is provided with a groove corresponding to the driving inclined groove, the connecting member comprises a first bearing and a pin, the first bearing is provided in the driving inclined groove, and the pin passes through the inner hole of the first bearing to be fixed to the groove of the lens barrel;

[0033] A second bearing is provided in the driving straight groove;

[0034] A second gasket is arranged between the first bearing and the second bearing and / or between the second bearing and the lens barrel and / or between the first bearing and the pin head.

[0035] In the technical solution of the present invention, by fixing the driving cylinder on the mounting bracket, the mounting strength is high, and the driving bevel groove is arranged on the driving cylinder to cooperate with the connecting member arranged on the lens barrel. Only by rotating the driving cylinder, the lens barrel can be driven to move forward and backward to achieve focusing. The lens barrel does not rotate directly, thereby avoiding the problem of the resolution not corresponding to the eccentricity changing with the rotation; in addition, by arranging the elastic structure to provide a forward elastic force when the lens barrel moves forward and backward, the connecting member and the driving bevel groove are pressed against each other in the front and back directions, the gap between the connecting member and the driving bevel groove is reduced, and the accuracy of the focusing structure is improved. By such an arrangement, a focusing structure that can achieve high-precision and high-stability focusing is provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0037] Figure 1 A schematic structural diagram of an embodiment of a focusing structure provided by the present invention;

[0038] Figure 2 for Figure 1 A schematic diagram of the focusing structure from another perspective;

[0039] Figure 3 for Figure 2 Cross-section of the middle drive cylinder at AA;

[0040] Figure 4 for Figure 1 Cross-sectional view of the drive motor and encoder at BB.

[0041] Description of Figure Numbers:

[0042] 100. Focusing structure; 1. Mounting bracket; 2. Driving cylinder; 21. Driving inclined groove; 22. Annular rack; 23. First annular groove; 24. Second annular groove; 3. Lens barrel; 31. Groove; 4. Connector; 41. First bearing; 42. Pin; 42. Second bearing; 5. Elastic structure; 51. Guide shaft; 52. Spring; 6. Driving motor; 61. Output shaft; 62. First gear; 7. Encoder; 71. Encoder shaft; 72. Magnetic grid; 73. Encoder body; 74. Torsion spring; 75. Second gear; 8. Fixed cylinder; 81. Driving straight groove; 82. Threaded hole; 9. Gasket structure; 91. First gasket; 92. Second gasket; 10. Connecting plate; 11. Cover plate.

[0043] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0044] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0045] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0046] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features limited to "first" and "second" may explicitly or implicitly include at least one of the features. In addition, if "and / or" or "and / or" appears in the full text, its meaning includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or solutions that satisfy both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0047] The present invention provides a focusing structure 100 .

[0048] See also Figure 1In one embodiment of the present invention, the focusing structure 100 includes a mounting bracket 1, a driving tube 2, a lens barrel 3 and an elastic structure 5, wherein the driving tube 2 is arranged on the mounting bracket 1 along the front-back direction and can rotate along the axis of the front-back direction, the peripheral wall of the driving tube 2 is formed with at least one driving inclined groove 21, the driving inclined groove 21 extends along the front-back direction, and the front end of the driving inclined groove 21 and the rear end of the driving inclined groove 21 are staggered along the circumferential direction of the lens barrel 3; the lens barrel 3 is movably mounted in the fixing tube 8 along the front-back direction, at least one connecting member 4 is fixed on the outer peripheral wall of the lens barrel 3, and the connecting member 4 is slidably mounted in the driving inclined groove 21, when the driving tube 2 rotates relative to the lens barrel 3, the driving inclined groove 21 drives the connecting member 4 to drive the lens barrel 3 to move forward and backward; and the elastic structure 5 is arranged between the rear end of the lens barrel 3 and the mounting bracket 1, so as to provide elastic force when the lens barrel 3 moves forward.

[0049] It should be noted that the number of the driving slant grooves 21 can be set based on the actual adjustment stroke and adjustment accuracy of the focusing structure 100. Since the current common driving barrel 2 is subjected to force at one or two points, the stability is poor. Preferably, the driving slant grooves 21 are set to three, and the connecting members 4 are also set to three. The three connecting members 4 and the three driving slant grooves 21 form a stable three-point structure, further improving the stability and accuracy of the movement of the lens barrel 3. The stability of the performance of the built-in lens barrel 3 during transportation is guaranteed by three points, and stable force is achieved.

[0050] In the technical solution of the present invention, the driving cylinder 2 is fixed on the mounting bracket 1, and the mounting strength is high. The driving inclined groove 21 is arranged on the driving cylinder 2, and cooperates with the connecting member 4 arranged on the lens barrel 3. Only by rotating the driving cylinder 2, the lens barrel 3 can be driven to move forward and backward to achieve focusing. The lens barrel 3 does not rotate directly, thereby avoiding the problem of the resolution not corresponding to the eccentricity changing with the rotation; in addition, the elastic structure 5 is arranged to provide a forward elastic force when the lens barrel 3 moves forward and backward, so that the connecting member 4 and the driving inclined groove 21 are pressed against each other in the front and back directions, the gap between the connecting member 4 and the driving inclined groove 21 is reduced, and the precision of the focusing structure 100 is improved. By such a setting, a focusing structure 100 capable of achieving high-precision and high-stability focusing is provided.

[0051] Specifically, in order to provide a longer service life, in one embodiment of the present invention, the peripheral wall of the lens barrel 3 is provided with a groove corresponding to the driving inclined groove 21; the connecting member 4 includes a first bearing 41 and a pin 42, the first bearing 41 is provided in the driving inclined groove 21; the pin 42 passes through the inner hole of the first bearing 41 to be fixed to the groove of the lens barrel 3, and by providing the first bearing 41, rolling friction is generated between the screw and the driving inclined groove 21, thereby reducing wear and improving the service life of the focusing structure 100. It can be understood that the connecting member 4 can also be a first protrusion provided along the peripheral side of the lens barrel 3 and the first protrusion cooperates with the driving inclined groove 21, and the first protrusion passes through the inner hole of the first bearing 41 to be fixed to the driving inclined groove 21.

[0052] In addition, in one embodiment of the present invention, the focusing structure 100 also includes a connecting plate and a cover plate, the connecting plate is fixedly connected to the mounting bracket 1, and is arranged corresponding to the rear end surface of the driving cylinder 2; the cover plate is arranged to cover the mounting bracket 1, and the cover plate includes a plurality of through holes for accommodating the driving cylinder 2, the driving motor 6 and the encoder; the elastic structure 5 includes at least one guide shaft 51 and at least one spring 52, the guide shaft 51 is arranged between the cover plate and the connecting plate along the front-back direction, and the guide shaft 51 passes through the rear end surface of the lens barrel 3; the spring 52 is sleeved on the The guide shaft 51 is arranged on the guide shaft 51, and the two ends of the spring 52 are respectively in contact with the front end surface of the connecting plate and the rear end surface of the lens barrel 3 to provide elastic force when the lens barrel 3 moves forward and backward. By arranging the cover plate and the connecting plate, the driving cylinder 2 is further fixed to improve the stability of the driving device. In addition, the spring 52 is respectively arranged at both ends of the spring 52 to provide a forward elastic force when the lens barrel 3 moves forward and backward, so that the connecting member 4 and the driving inclined groove 21 are pressed tightly in the front and rear directions, the gap between the connecting member 4 and the driving inclined groove 21 is reduced, and the accuracy of the focusing structure 100 is improved. It is understandable that in order to avoid focusing components such as the sensor in the middle of the lens barrel 3, the guide shaft 51 and the spring 52 are difficult to be arranged near the middle, which leads to uneven force on the rear end surface of the lens barrel 3 and easy to cause tilting perpendicular to the axial direction; for this reason, the guide shaft 51 and the spring 52 can be provided in plurality, and the plurality of guide shafts 51 are arranged at intervals around the rear end surface of the lens. In the present embodiment, three guide shafts 51 are provided, and three springs 52 are also provided. The torques perpendicular to the axial direction formed by the three springs 52 offset each other, thereby jointly providing a stable forward and backward elastic force.

[0053] In one embodiment of the present invention, the focusing structure 100 also includes a driving motor 6 arranged on the mounting bracket 1, and the driving motor 6 includes an output shaft 61 extending in the front-to-back direction, and a first gear 62 is arranged on the output shaft 61; the outer peripheral wall of the driving cylinder 2 is provided with an annular rack 22 meshing with the first gear 62; wherein, through the coordination of the gear and rack, the driving motor 6 can accurately control the rotation angle of the driving cylinder 2, and then accurately control the distance of the forward and backward movement of the lens barrel 3 to complete the focusing; it can be understood that the present invention does not limit the method of driving the driving cylinder 2 to rotate, and for the convenience of adjustment, the driving cylinder 2 can also be manually rotated to complete the focusing.

[0054] In one embodiment of the present invention, the focusing structure 100 includes an encoder 7 for detecting the rotation angle of the driving cylinder 2, and the encoder 7 includes an encoder shaft 71, a magnetic grid 72, and an encoder body 73; wherein the encoder shaft 71 extends in the front-to-back direction, and a second gear meshing with the annular rack 22 is provided on the encoder shaft 71; the magnetic grid 72 is provided at one end of the encoder shaft 71 away from the second gear; the encoder body 73 is fixedly connected to the mounting bracket 1, and is provided to cover the magnetic grid 72.

[0055] It should be noted that the encoder is a sensor used to convert mechanical motion into electrical signal output, which is used to accurately measure and feedback the focus position or motion state; the magnetic grid 72 is one of the key components of the encoder, which is composed of a series of magnetic materials arranged according to a specific rule. However, in order to reduce mechanical wear, the magnetic grid 72 is usually non-contact, and this method can also reduce the error caused by mechanical friction; the encoder body 73 covers the magnetic grid 72, and when the magnetic grid 72 moves along the encoder body 73 paired with it, it can sense the change of the magnetic field, so as to accurately calculate the relative displacement; it can also physically protect the sensitive electronic components inside the encoder to prevent damage to them by external factors such as dust, moisture, impact, etc. This helps to extend the service life of the encoder and maintain its stable performance.

[0056] When the driving motor 6 is used to drive the driving cylinder 2 to rotate, the second gear on the encoder shaft 71 is meshed with the annular rack 22 and rotated synchronously, thereby driving the magnetic grid 72 and the encoder body 73 to rotate relative to each other, thereby detecting the rotation angle of the driving cylinder 2 in real time, thereby improving the accuracy and reliability of the focusing system mechanism.

[0057] In addition, it can be understood that if the second gear is not tightly abutted against the annular rack 22, when the driving cylinder 2 rotates, it will go through a period of idle travel before meshing with the second gear, thereby causing the angle measured by the encoder to be smaller, affecting the measurement accuracy; in addition, the magnetic grid 72 is usually non-contact. If it contacts the encoder body 73 during transportation and use, it will cause damage to the magnetic grid 72. For this reason, in one embodiment of the present invention, the encoder also includes a torsion spring 74, which is sleeved on the outside of the encoder shaft 71, and one end of the torsion spring 74 in the front-to-back direction is abutted against the mounting bracket 1, and at least a part of the other end is arranged in the inner hole of the second gear, so as to apply a pre-tightening force along the circumference of the encoder shaft 71 to the second gear when the annular rack 22 drives the second gear to rotate, and to apply a pre-tightening force along the direction away from the encoder body 73 to the encoder shaft 71. By setting the torsion spring 74, a pre-tightening force is applied to the encoder shaft 71 in a direction away from the encoder body 73, so that a stable gap is provided between the magnetic grid 72 and the encoder body 73, thereby preventing the magnetic grid 72 from being damaged; the torsion spring 74 also applies a pre-tightening force along the circumference of the encoder shaft 71 to the second gear, so that the second gear is always tightly fitted with the encoder, eliminating the gap and improving the measurement accuracy.

[0058] In addition, it can be understood that the torsion spring can also be a spring and a torsion spring respectively arranged on the encoder shaft, so as to apply a preload force to the encoder shaft 71 along the direction away from the encoder body 73, and apply a preload force to the second gear along the circumference of the encoder shaft 71.

[0059] In order to make the driving cylinder 2 more stable when driving the lens barrel 3 to move forward and backward, in one embodiment of the present invention, the focusing structure 100 also includes a fixed cylinder 8, which is arranged between the driving cylinder 2 and the lens barrel 3 in the front-to-back direction, and the peripheral wall of the fixed cylinder 8 is formed with at least one driving straight groove 81 corresponding to the driving inclined groove 21, and the driving straight groove 81 extends in the front-to-back direction; the connecting member 4 passes through the driving straight groove 81 to slide with the driving inclined groove 21, and when the driving cylinder 2 rotates relative to the lens barrel 3, the connecting member 4 slides along the driving straight groove 81, and when the driving cylinder 2 rotates relative to the fixed cylinder 8, the connecting member 4 is constrained by the side wall of the driving straight groove 81, so that the connecting member 4 can only move along the driving straight groove 81, thereby driving the lens barrel 3 to move only in the front-to-back direction to avoid circumferential deviation. It is understandable that the driving straight groove 81 can also be arranged on the circumferential side of the lens barrel 3, and the first protrusion is provided on the inner wall of the fixed barrel 8, but considering the actual size of the lens barrel 3 and the fixed barrel 8, as well as the specific layout, it can be arranged according to actual needs.

[0060] Further, in one embodiment of the present invention, a second bearing 42 is provided in the driving straight groove 81, and the connecting member 4 at least partially passes through the inner hole of the second bearing 42 and extends into the driving inclined groove 21. By providing the second bearing 42, rolling friction is generated between the connecting member 4 and the driving straight groove 81, thereby reducing wear and improving the service life of the focusing structure 100. It can be understood that, in another embodiment, when the connecting member 4 includes the pin 42 and the first bearing 41, the pin 42 can be slidably connected to the driving inclined groove 21 and the driving straight groove 81 through the first bearing 41 and the second bearing 42, respectively, thereby further reducing wear and improving the service life.

[0061] In addition, it is understandable that during transportation and use, the bearing will inevitably vibrate and axially displace along the pin 42, thereby causing the bearing to fall off; for this reason, in one embodiment of the present invention, the peripheral wall of the lens barrel 3 is provided with a groove corresponding to the driving inclined groove 21; the connecting member 4 includes a first bearing 41 and a pin 42, the first bearing 41 is arranged in the driving inclined groove 21; the pin 42 passes through the inner hole of the first bearing 41 to be fixed to the groove of the lens barrel 3; the focusing structure 100 includes a gasket structure 9, the gasket structure 9 includes a first gasket 91, the first gasket 91 is arranged between the first bearing 41 and the lens barrel 3 and / or between the first bearing 41 and the nail head of the pin 42; by providing the first gasket 91, the spacing between the first bearing 41 and the lens barrel 3 and between the first bearing 41 and the nail head of the pin 42 is maintained, thereby eliminating the gap and improving the transmission accuracy;

[0062] Further, in one embodiment of the present invention, the peripheral wall of the lens barrel 3 is provided with a groove corresponding to the driving inclined groove 21; the connecting member 4 includes a first bearing 41, a second bearing 42 and a pin 42, the first bearing 41 is arranged in the driving inclined groove 21; the pin 42 passes through the inner hole of the first bearing 41 to be fixed to the groove of the lens barrel 3, the second bearing 42 is sleeved in the driving straight groove 81, and the pin 42 is rotatably matched with the driving straight groove 81 through the second bearing 42; when the connecting member 4 also includes a second bearing 42, the first gasket 91 can also be arranged between the first bearing 41 and the second bearing 42, between the second bearing 42 and the lens barrel 3, and between the first bearing 41 and the nail head of the pin 42. It can be understood that the first gasket 91 can be selectively arranged, and in order to better maintain and eliminate the gap, in the present embodiment, the first gasket 91 is arranged between the first bearing 41 and the second bearing 42, between the second bearing 42 and the lens barrel 3, and between the first bearing 41 and the nail head of the pin 42.

[0063] In addition, since the fixed tube 8 is arranged between the driving tube 2 and the lens tube 3, its rear end face is not directly abutted against the mounting bracket 1. In order to increase the stability of the fixed tube 8, in one embodiment of the present invention, a threaded hole 82 is provided on the rear end face of the fixed tube 8 for screw connection, and the rear end face of the screw head abuts against the mounting bracket 1; the second gasket 92 is arranged between the screw head and the rear end face of the fixed tube 8; wherein, it can be understood that if the sum of the thickness of the second gasket 92 and the screw head is H, and the distance between the rear end face of the fixed tube 8 and the mounting bracket 1 is h, then H is slightly greater than h, so that the second gasket 92 and the screw head are interference fit between the rear end face of the fixed tube 8 and the mounting bracket 1, eliminating the gap between the rear end face of the fixed tube 8 and the mounting bracket 1, and increasing the stability of the fixed tube 8.

[0064] Furthermore, in order to prevent the lens barrel 3 from colliding with the driving cylinder 2 and the mounting bracket 1 during the backward movement of the lens barrel 3 for focusing, in one embodiment of the present invention, a limit block is provided on the rear end face of the lens barrel 3 to limit the backward movement range of the lens barrel 3; wherein the limit block can be an elastic rubber block or spring 52, so that the lens barrel 3 is in soft contact with the driving cylinder 2 and the mounting bracket 1, thereby preventing the lens barrel 3 from being displaced too much backward and causing damage.

[0065] It can be understood that since the driving cylinder 2 rotates along its front-to-back axis, wear will be caused to the front and rear end faces of the driving cylinder 2. For this reason, in one embodiment of the present invention, the front end of the fixed cylinder 8 contacts the side opposite to the driving cylinder 2, and a first annular groove 23 is formed at the front end of the fixed cylinder 8 and the side opposite to the driving cylinder 2 for accommodating balls, thereby adjusting the connection mode between the fixed cylinder 8 and the driving cylinder 2 to a rolling connection, thereby reducing wear; in addition, the focusing structure 100 also includes a connecting plate, which is fixedly connected to the mounting bracket 1 and is arranged corresponding to the rear end face of the driving cylinder 2, and the side faces of the connecting plate and the rear end face of the driving cylinder 2 are respectively formed with second annular grooves 24 for accommodating balls, thereby adjusting the connection mode between the connecting plate and the side faces opposite to the rear end face of the driving cylinder 2 to a rolling connection, thereby reducing wear.

[0066] The above description is only an exemplary embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the technical concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A focusing structure, characterized in that: include: Mounting bracket; A driving cylinder is arranged on the mounting bracket in the front-to-back direction and can rotate along the axis in the front-to-back direction, and a peripheral wall of the driving cylinder is formed with at least one driving inclined groove, the driving inclined groove extends in the front-to-back direction, and a front end of the driving inclined groove and a rear end of the driving inclined groove are staggered along the circumference of the lens barrel; The lens barrel is movably mounted in the fixed barrel in the front-back direction, and at least one connecting member is fixed to the outer peripheral wall of the lens barrel, and the connecting member is slidably mounted in the driving inclined groove. When the driving barrel rotates relative to the lens barrel, the driving inclined groove drives the connecting member to drive the lens barrel to move forward and backward; as well as, The elastic structure is arranged between the rear end of the lens barrel and the mounting bracket, and is used for providing a forward elastic force when the lens barrel moves forward and backward.

2. The focusing structure according to claim 1, characterized in that: The peripheral wall of the lens barrel is provided with a groove corresponding to the driving inclined groove; The connecting piece comprises: A first bearing is disposed in the driving chute; A pin passes through the inner hole of the first bearing to be fixed in the groove of the lens barrel.

3. The focusing structure according to claim 1, characterized in that: The focusing structure further comprises a connecting plate and a cover plate, wherein the connecting plate is fixedly connected to the mounting bracket and is arranged corresponding to the rear end surface of the driving tube; the cover plate is arranged to cover the mounting bracket, and the cover plate comprises a plurality of through holes for accommodating and making way for the driving tube; The elastic structure comprises: At least one guide shaft is arranged between the cover plate and the connecting plate along the front-rear direction, and the guide shaft passes through the rear end surface of the lens barrel; At least one spring is sleeved on the guide shaft, and two ends of the spring are respectively in contact with the front end surface of the connecting plate and the rear end surface of the lens barrel, so as to provide elastic force when the lens barrel moves forward and backward.

4. The focusing structure according to claim 1, characterized in that: The focusing structure further comprises a driving motor disposed on the mounting bracket, the driving motor comprising an output shaft extending in a front-rear direction, and a first gear is disposed on the output shaft; The outer peripheral wall of the driving cylinder is provided with an annular rack meshing with the first gear.

5. The focusing structure according to claim 4, characterized in that: The focusing structure includes an encoder disposed on the mounting bracket for detecting the rotation angle of the driving cylinder, and the encoder includes: An encoder body, the encoder body being fixedly connected to the mounting bracket; An encoder shaft extending in the front-rear direction, the encoder shaft being provided with a second gear meshing with the annular rack; A magnetic grid, wherein the magnetic grid is arranged on an end of the encoder shaft away from the second gear, and the encoder body covers the magnetic grid; A torsion spring is sleeved on the outside of the encoder shaft, one end of the torsion spring in the front-to-back direction is in contact with the mounting bracket, and at least a part of the other end is arranged in the inner hole of the second gear, so as to apply a pre-tightening force along the circumference of the encoder shaft to the second gear when the annular rack drives the second gear to rotate, and to apply a pre-tightening force along the direction away from the encoder body to the encoder shaft.

6. The focusing structure according to claim 1, characterized in that: The focusing structure further comprises a fixed cylinder, which is arranged between the driving cylinder and the lens barrel along the front-rear direction, and the peripheral wall of the fixed cylinder is formed with at least one driving straight groove corresponding to the driving oblique groove, and the driving straight groove extends along the front-rear direction; The connecting member passes through the driving straight groove to slide with the driving oblique groove. When the driving cylinder rotates relative to the lens barrel, the connecting member slides along the driving straight groove.

7. The focusing structure according to claim 6, characterized in that: A second bearing is arranged in the driving straight groove, and the connecting member at least partially passes through the inner hole of the second bearing and extends into the driving inclined groove.

8. The focusing structure according to claim 6, characterized in that: A first annular groove is formed at the front end of the fixing cylinder and at the side opposite to the driving cylinder, respectively, for accommodating the ball; and / or, The focusing structure also includes a connecting plate, which is fixedly connected to the mounting bracket and arranged corresponding to the rear end face of the driving cylinder. The side surfaces of the connecting plate opposite to the rear end face of the driving cylinder are respectively formed with second annular grooves for accommodating balls.

9. The focusing structure according to claim 6, characterized in that: The rear end surface of the fixing cylinder is provided with a threaded hole; The focusing structure comprises a connecting screw, comprising a screw head, wherein the connecting screw passes through the threaded hole and the screw head abuts against the mounting bracket; A first gasket is arranged between the screw head and the rear end surface of the fixing tube.

10. The focusing structure according to claim 6, characterized in that: The peripheral wall of the lens barrel is provided with a groove corresponding to the driving inclined groove, the connecting member comprises a first bearing and a pin, the first bearing is arranged in the driving inclined groove, and the pin passes through the inner hole of the first bearing to be fixed in the groove of the lens barrel; A second bearing is provided in the driving straight groove; A second gasket is arranged between the first bearing and the second bearing and / or between the second bearing and the lens barrel and / or between the first bearing and the pin head.

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