Zoom adapter and endoscope

Abstract

The utility model relates to a kind of zoom adapter and endoscope of all change. The zoom adapter of all change, comprising: adapter main body, including main cylinder and flange, lens cavity is opened in main cylinder with axis along optical axis direction, flange is fixed in main cylinder end and is used for fixed sensor;Two variable magnification rings, interval setting in lens cavity along optical axis direction, the outer circumferential surface of both is fixed with at least one guide pillar;Variable magnification adjusting part, setting in the outside of main cylinder, main cylinder is throughly opened with the curve slot corresponding to each guide pillar, guide pillar is through corresponding curve slot to with variable magnification adjusting part connection, to drive variable magnification ring along optical axis direction by rotating variable magnification adjusting part and move;Limiting surface is set in adapter main body, limiting surface is used to limit the movement limit position of variable magnification ring along optical axis direction, when variable magnification ring is located in movement limit position, the guide pillar of this variable magnification ring is located in the main body section of corresponding curve slot;It fundamentally avoids the risk of guide pillar jamming caused by the end section of curve slot processing defect.

Description

Technical Field

[0001] This utility model relates to the field of endoscope-related technology, and in particular to a zoom adapter and an endoscope. Background Technology

[0002] As a key component of the endoscopic imaging system, the zoom adapter's zoom stability directly affects the quality of the surgical field of view. In the traditional design, the adapter achieves axial movement of the zoom group through the cooperation of the curved groove opened in the main tube and the zoom ring guide post. The movement limit of the zoom ring is mainly completed by the rigid blocking guide post at the end of the curved groove.

[0003] However, due to limitations in the main tube metal processing technology, the transition at the root region of the curved groove end is not smooth, which can easily produce steep transitions or micro-burrs. When the zoom ring guide post moves to the end of the curved groove, mechanical jamming can easily occur, resulting in lens movement due to zoom ring imbalance, which in turn leads to image jitter. In high-precision minimally invasive surgical scenarios, such jitter can significantly increase operational risks and cannot meet the clinical requirements for continuous imaging stability. Utility Model Content

[0004] Therefore, it is necessary to provide a zoom adapter and endoscope that can effectively improve image shake in current zoom adapters.

[0005] This application first provides a zoom adapter, including: The adapter body includes a main cylinder and a flange. The main cylinder has a lens cavity with its axis along the optical axis. The flange is fixed to the end of the main cylinder and is used to fix the sensor. Two zoom rings are spaced apart in the lens cavity along the optical axis, and at least one guide post is fixed on the outer peripheral surface of each ring. A zoom adjustment component is disposed on the outside of the main cylinder. The main cylinder has a through-cut curved groove corresponding to each of the guide posts. The guide posts pass through the corresponding curved grooves to connect with the zoom adjustment component, so that the zoom ring can be driven to move along the optical axis by rotating the zoom adjustment component. The adapter body has a limiting surface, which is used to limit the movement limit position of the zoom ring along the optical axis. The curved groove includes a main body segment and end segments located at both ends of the main body segment. When the zoom ring is at the movement limit position, each of the guide posts of the zoom ring is located in the main body segment corresponding to the curved groove.

[0006] In one embodiment, the zoom adapter further includes a fixing ring located between the two zoom rings and fixed to the main tube, wherein the end face of the fixing ring along the optical axis is the limiting surface.

[0007] In one embodiment, the inner wall of the lens cavity is provided with a limiting step, and the end face of the limiting step along the optical axis is the limiting surface.

[0008] In one embodiment, the flange has a mounting groove, the end of the main cylinder is inserted into the mounting groove, and the bottom wall of the mounting groove is the limiting surface.

[0009] In one embodiment, the zoom adapter further includes a fixing ring located between the two zoom rings and fixed to the main tube, the inner wall of the lens cavity is provided with a limiting step, the flange is provided with a mounting groove, and the end of the main tube is inserted into the mounting groove; The zoom ring, which is away from the flange along the optical axis, has its end face away from the flange abutting against the limiting step, and its end face close to the flange abutting against the fixing ring. The zoom ring, which is close to the flange along the optical axis, has its end face away from the flange abutting against the fixing ring, and its end face close to the flange abutting against the bottom wall of the mounting groove.

[0010] In one embodiment, the flange is provided with an installation groove and a limiting groove. The limiting groove includes a first limiting groove and a second limiting groove. The two ends of the first limiting groove along the optical axis are respectively connected to the installation groove and the second limiting groove. The second limiting groove extends in a direction perpendicular to the optical axis. The main cylinder is fixed with a limiting member corresponding to the limiting groove on the side near the flange; The end of the main cylinder is inserted into the mounting groove, the limiting member is engaged in the second limiting groove through the first limiting groove, the limiting member abuts against the inner wall of the second limiting groove along the optical axis, and the main cylinder and the flange are fixed along the optical axis by screws.

[0011] In one embodiment, the bottom wall of the mounting groove is provided with a plurality of limiting grooves at equal intervals along the circumferential direction, and each of the second limiting grooves extends along the same circumferential direction; the end face of the main cylinder near the flange is fixed with a plurality of limiting members corresponding to each of the limiting grooves.

[0012] In one embodiment, the flange and the main cylinder are made of a first material, and the screw is made of a second material, wherein the hardness and density of the first material are both less than those of the second material.

[0013] In one embodiment, a gasket is also provided between the main cylinder and the flange.

[0014] This application also provides an endoscope including the above-described zoom adapter.

[0015] The aforementioned zoom adapter independently assumes the axial limiting function of the zoom ring through the limiting surface within the adapter body. This eliminates the need for rigid limiting of each guide post at the end of the curved groove. In other words, the guide post does not contact the end section, which is prone to jamming due to processing defects, when it reaches its extreme position. This fundamentally avoids the risk of guide post jamming caused by poor processing of the end section of the curved groove, thereby preventing the zoom ring from causing unexpected displacement or vibration due to jamming. This ensures that the lens movement trajectory strictly follows the optical design requirements, and the field of view imaging is free of jumps. This meets the stringent requirements of minimally invasive surgery for image stability and reduces operational risks. Attached Figure Description

[0016] Figure 1 This is a perspective view of the zoom adapter of this application; Figure 2 for Figure 1 Exploded view; Figure 3 for Figure 1 Exploded view of the main body of the adapter; Figure 4 for Figure 1 A sectional view; Figure 5 for Figure 3 A schematic diagram of the middle flange from another angle; Figure 6 This is a stereoscopic view of the endoscope used in this application.

[0017] Reference numerals: 10, adapter body; 11, main tube; 111, lens cavity; 111a, limiting step; 112, curved groove; 113, limiting component; 12, flange component; 121, mounting groove; 122, limiting groove; 122a, first limiting groove; 122b, second limiting groove; 13, gasket; 21, zoom ring; 211, guide post; 22, fixing ring; 23, focusing ring; 31, zoom adjustment component; 32, focusing adjustment component. Detailed Implementation

[0018] To make the above-mentioned objects, features, and advantages of this utility model more apparent and understandable, the specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a full understanding of this utility model. However, this utility model 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 utility model. Therefore, this utility model is not limited to the specific embodiments disclosed below.

[0019] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0020] Furthermore, 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 indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this utility model, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0021] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "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, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0022] In this utility model, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0023] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0024] Please combine Figure 1 , Figure 2 as well as Figure 3 As shown, this application first provides a zoom adapter, including: an adapter body 10, including a main tube 11 and a flange 12, wherein a lens cavity 111 with its axis along the optical axis is formed inside the main tube 11, and the flange 12 is fixed to the end of the main tube 11 and used to fix a sensor; two zoom rings 21, which are spaced apart in the lens cavity 111 along the optical axis, and at least one guide post 211 is fixed on the outer circumference of both rings; and a zoom adjustment member 31, which is disposed on the outside of the main tube 11, wherein the main tube 11 has a through-hole corresponding to each guide post 211. The curved groove 112 has guide posts 211 that pass through it and connect to the zoom adjustment member 31, so that the zoom ring 21 can be driven to move along the optical axis by rotating the zoom adjustment member 31. The adapter body 10 has a limiting surface that limits the movement limit position of the zoom ring 21 along the optical axis. The curved groove 112 includes a main body section and end sections at both ends of the main body section. When the zoom ring 21 is at the movement limit position, each guide post 211 of the zoom ring 21 is located in the main body section of the corresponding curved groove 112.

[0025] It should be noted that the limiting surface is used to limit the movement limit position of the zoom ring 21 along the optical axis. This means that the limiting surface restricts the movement stroke of the zoom ring 21 so that the zoom ring 21 has a movement limit position. That is, when the zoom ring 21 moves along the optical axis to abut against the limiting surface, the zoom ring 21 is located at this movement limit position.

[0026] In this application, the limiting surface within the adapter body 10 independently assumes the axial limiting function of the zoom ring 21, so that each guide post 211 no longer relies on the end of the curved groove 112 for rigid limiting. In other words, when the guide post 211 moves to its limit position, it does not contact the end section that is prone to jamming due to processing defects. This fundamentally avoids the risk of guide post 211 jamming due to poor processing of the end section of the curved groove 112, thereby avoiding unexpected displacement or vibration of the zoom ring 21 due to jamming. This ensures that the lens movement trajectory strictly follows the optical design requirements, and the field of vision imaging is free of jumps, meeting the stringent requirements of image stability for minimally invasive surgery and reducing operational risks.

[0027] In some embodiments, the zoom adapter further includes a focusing ring 23 and a focusing adjustment member 32. The focusing ring 23 is located inside the lens cavity 111 and is located on the side of the zoom ring 21 away from the flange 12 along the optical axis. The focusing adjustment member 32 is disposed on the outside of the main tube 11. The focusing ring 23 is also provided with a guide post 211, which passes through the corresponding curved groove 112 to connect with the focusing adjustment member 32, so that the focusing ring 23 can be driven to move along the optical axis by rotating the focusing adjustment member 32.

[0028] In some embodiments, the zoom adjustment member 31 and the focus adjustment member 32 are both annularly sleeved on the main cylinder 11 to facilitate user operation and adjustment.

[0029] In some embodiments, the inner walls of the zoom adjustment member 31 and the focus adjustment member 32 are provided with straight grooves corresponding to each guide post 211. The straight grooves extend along the optical axis, and the guide posts 211 pass through the corresponding curved grooves 112 to the corresponding straight grooves.

[0030] Specifically, when the zoom adjustment component 31 or the focus adjustment component 32 rotates, the inner wall of the straight groove abuts against the corresponding guide post 211, thereby driving the zoom ring 21 or the focus ring 23 to rotate relative to the main cylinder 11 through the guide post 211. Since the guide post 211 passes through the curved groove 112, under the limiting action of the curved groove 112, the guide post 211 will move along the length direction of the curved groove 112, thereby driving the zoom ring 21 or the focus ring 23 to move along the optical axis.

[0031] More specifically, the main body section of the curved groove 112 is opened around the main cylinder 11 along the optical axis.

[0032] Please combine Figure 2 as well as Figure 4 As shown, in some embodiments, the zoom adapter further includes a fixing ring 22 located between the two zoom rings 21 and fixed to the main tube 11, and the end face of the fixing ring 22 along the optical axis is a limiting surface.

[0033] As an essential lens assembly structure of the optical system, the fixing ring 22 has its end face reused as a limiting surface in this application. This eliminates the need to separately process the limiting surface on the inner wall of the main tube 11 or add additional limiting components as limiting surfaces, thereby reducing the structural complexity of the adapter body 10 and saving axial space. This is especially suitable for adapter design in devices such as miniaturized endoscopes.

[0034] Specifically, the retaining ring 22 is fixed to the main cylinder 11 by a screw that passes through the main cylinder 11 in the radial direction.

[0035] It is worth mentioning that in this application, the lens structures such as the zoom ring 21, the fixing ring 22, and the focusing ring 23 all include a lens mounting base and at least one lens fixed in the lens mounting base. The lens mounting base is used to fix the lens and connect it to the main tube 11. For example, the guide posts 211 of the zoom ring 21 and the focusing ring 23 are fixed to the lens mounting base, and the lens mounting base of the fixing ring 22 is fixed to the main tube 11. Multiple lenses in the same lens mounting base are arranged along the optical axis.

[0036] Please combine Figure 4 as well as Figure 5 As shown, in some embodiments, the flange 12 has a mounting groove 121, the end of the main cylinder 11 is inserted into the mounting groove 121, and the bottom wall of the mounting groove 121 is a limiting surface.

[0037] Similarly, the flange 12 itself is an existing structure used to fix the sensor in the zoom adapter. In this application, it is reused as a limiting surface, which can also achieve the effect of simplifying the structure and improving space utilization.

[0038] Specifically, the opening of the lens cavity 111 is located at one end of the main tube 11 along the optical axis near the flange 12. Lens structures such as the zoom ring 21, the fixing ring 22, and the focusing ring 23 are installed into the lens cavity 111 through the opening of the lens cavity 111. Then, the end of the main tube 11 on this side is inserted into the mounting groove 121 of the flange 12 to prevent the lens structures in the lens cavity 111 from coming out through the opening.

[0039] Please combine Figure 3 as well as Figure 4 As shown, in some embodiments, a limiting step 111a is provided on the inner wall of the lens cavity 111, and the end face of the limiting step 111a along the optical axis is a limiting surface.

[0040] With this configuration, the positional accuracy of the limiting surface depends only on the machining accuracy of the main cylinder 11. Compared to the assembly errors that may be introduced by setting the limiting surface on other parts, the tolerance chain of machining the limiting step 111a on the inner wall of the lens cavity 111 and using it as the limiting surface is shorter, resulting in higher positional accuracy.

[0041] Please combine Figure 3 , Figure 4 as well as Figure 5 As shown, in some embodiments, the zoom adapter further includes a fixing ring 22 located between the two zoom rings 21 and fixed to the main tube 11, a limiting step 111a is provided on the inner wall of the lens cavity 111, and the flange 12 is provided with a mounting groove 121, the end of the main tube 11 is inserted into the mounting groove 121. The magnification ring 21, which is away from the flange 12 along the optical axis, has its end face away from the flange 12 abutting against the limiting step 111a, and its end face near the flange 12 abutting against the fixing ring 22; the magnification ring 21, which is near the flange 12 along the optical axis, has its end face away from the flange 12 abutting against the fixing ring 22, and its end face near the flange 12 abutting against the bottom wall of the mounting groove 121.

[0042] Please combine Figure 3 , Figure 5 as well as Figure 6 As shown, in some embodiments, the flange 12 is provided with a mounting groove 121 and a limiting groove 122. The limiting groove 122 includes a first limiting groove 122a and a second limiting groove 122b. The two ends of the first limiting groove 122a along the optical axis are respectively connected to the mounting groove 121 and the second limiting groove 122b. The second limiting groove 122b extends in a direction perpendicular to the optical axis. A limiting member 113 corresponding to the limiting groove 122 is fixedly provided on the side of the main cylinder 11 near the flange 12. The end of the main cylinder 11 is inserted into the mounting groove 121. The limiting member 113 is inserted into the second limiting groove 122b through the first limiting groove 122a. The limiting member 113 and the inner wall of the second limiting groove 122b abut against each other along the optical axis. The main cylinder 11 and the flange 12 are fixed along the optical axis by screws.

[0043] In this application, after installation, the limiting member 113 and the second limiting groove 122b abut against each other along the axial direction, so that the fitting structure can share part of the shaking force. The screws of the threaded connection between the main cylinder 11 and the flange 12 only need to resist the residual torque, and their stress is significantly reduced, thereby reducing or even avoiding the possibility of thread creep failure.

[0044] In some embodiments, after the limiting member 113 is inserted into the second limiting groove 122b through the first limiting groove 122a, the limiting member 113 can be inserted into the second limiting groove 122b by translating the main cylinder 11 relative to the flange 12, or the limiting member 113 can be inserted into the second limiting groove 122b by rotating the main cylinder 11 relative to the flange 12. As long as the limiting member 113 and the inner wall of the second limiting groove 122b can abut against each other along the optical axis after installation to share the force and reduce the risk of screw loosening, it is acceptable.

[0045] In addition, in some other embodiments, a limiting groove 122 may be provided at the end of the main cylinder 11, and a limiting member 113 corresponding to the limiting groove 122 may be fixed on the inner wall of the mounting groove 121 of the flange 12. As long as the limiting member 113 and the inner wall of the second limiting groove 122b can abut against each other along the optical axis after installation.

[0046] Please refer to Figure 5As shown, in some embodiments, the bottom wall of the mounting groove 121 is provided with a plurality of limiting grooves 122 at equal intervals along the circumferential direction, and each second limiting groove 122b extends along the same circumferential direction; a plurality of limiting members 113 corresponding to each limiting groove 122 are fixedly provided on the end face of the main cylinder 11 near the flange member 12.

[0047] In other words, the cross-section of each limiting groove 122 is L-shaped, and the L-shape faces the same direction, either counterclockwise or clockwise. This ensures that in this application, relative rotation can only occur when the main cylinder 11 rotates in the correct direction relative to the flange 12, and the holes for threaded connection can only be aligned when the rotation is in place. This achieves a guiding and physical anti-misalignment effect through the snap-fit ​​between the limiting groove 122 and the limiting member 113, reducing the installation difficulty of the zoom adapter in this application.

[0048] In some embodiments, the flange 12 and the main cylinder 11 are made of a first material, and the screws are made of a second material. The hardness and density of the first material are both lower than those of the second material, thereby reducing the overall weight of the equipment while ensuring sufficient structural strength.

[0049] Specifically, the first material is aluminum alloy, and the second material is carbon steel or stainless steel. The aluminum alloy material is relatively lightweight, which can significantly reduce the overall weight of the zoom adapter of this application and reduce the burden on doctors holding the endoscope for a long time during the operation. The carbon steel or stainless steel screw structure has higher strength, which can improve the fixation reliability between the flange 12 and the main cylinder.

[0050] It is worth mentioning that the aluminum alloy flange 12 and the main cylinder 11 have relatively low structural strength, and the threads in their threaded holes are more prone to failure due to shaking stress compared to other materials. However, in this application, the limiting member 113 and the second limiting groove 122b abut against each other along the axial direction, which can share the shaking stress and thus significantly reduce the possibility of thread failure.

[0051] Please refer to Figure 3 as well as Figure 4 As shown, in some embodiments, a gasket 13 is also provided between the main cylinder 11 and the flange 12.

[0052] Since the sensor is fixed to the flange 12 by active alignment (AA) dispensing, the process requires the dispensing thickness to be less than a certain limit. However, due to the accumulation of tolerances such as machining tolerances and assembly tolerances between parts, the dispensing thickness exceeds the limit in some cases when the zoom adapter is in focus.

[0053] In this application, the gasket 13 is placed between the main cylinder 11 and the flange 12, so that the axial tolerance can be compensated in real time by adjusting the thickness of the gasket 13, thereby eliminating the correlation between the adhesive thickness and the focusing accuracy. This allows the adhesive thickness to be strictly controlled within the limit value, and the optical focus can be finely adjusted to the imaging surface by adjusting the thickness of the gasket 13, while ensuring the bonding strength and image clarity.

[0054] Please refer to Figure 6 As shown, this application also provides an endoscope including the above-described zoom adapter.

[0055] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0056] The embodiments described above are merely illustrative of several implementations of this utility model, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these all fall within the protection scope of this utility model. Therefore, the protection scope of this utility model patent should be determined by the appended claims.

Claims

1. A zoom adapter, characterized in that, include: The adapter body (10) includes a main cylinder (11) and a flange (12). The main cylinder (11) has a lens cavity (111) with its axis along the optical axis. The flange (12) is fixed to the end of the main cylinder (11) and is used to fix the sensor. Two zoom rings (21) are spaced apart in the lens cavity (111) along the optical axis, and at least one guide post (211) is fixed on the outer peripheral surface of both rings. A zoom adjustment component (31) is disposed on the outside of the main cylinder (11). The main cylinder (11) has a through-cut curved groove (112) corresponding to each of the guide posts (211). The guide posts (211) pass through the corresponding curved grooves (112) to connect with the zoom adjustment component (31) so that the zoom ring (21) can be driven to move along the optical axis by rotating the zoom adjustment component (31). The adapter body (10) is provided with a limiting surface, which is used to limit the movement limit position of the zoom ring (21) along the optical axis. The curved groove (112) includes a main body segment and end segments located at both ends of the main body segment. When the zoom ring (21) is located at the movement limit position, each of the guide posts (211) of the zoom ring (21) is located in the main body segment corresponding to the curved groove (112).

2. The zoom adapter according to claim 1, characterized in that, The zoom adapter also includes a fixing ring (22) located between the two zoom rings (21) and fixed to the main tube (11), the end face of the fixing ring (22) along the optical axis is the limiting surface.

3. The zoom adapter according to claim 1, characterized in that, The inner wall of the lens cavity (111) is provided with a limiting step (111a), and the end face of the limiting step (111a) along the optical axis is the limiting surface.

4. The zoom adapter according to claim 1, characterized in that, The flange (12) has an installation groove (121), and the end of the main cylinder (11) is inserted into the installation groove (121). The bottom wall of the installation groove (121) is the limiting surface.

5. The zoom adapter according to any one of claims 1 to 4, characterized in that, The zoom adapter also includes a fixing ring (22) located between the two zoom rings (21) and fixed to the main tube (11). The inner wall of the lens cavity (111) is provided with a limiting step (111a). The flange (12) is provided with a mounting groove (121). The end of the main tube (11) is inserted into the mounting groove (121). The magnification ring (21) that is away from the flange (12) along the optical axis can abut against the limiting step (111a) on the side away from the flange (12) and can abut against the fixing ring (22) on the side close to the flange (12). The magnification ring (21) that is close to the flange (12) along the optical axis can abut against the fixing ring (22) on the side away from the flange (12) and abut against the bottom wall of the mounting groove (121) on the side close to the flange (12).

6. The zoom adapter according to claim 1, characterized in that, The flange (12) is provided with an installation groove (121) and a limiting groove (122). The limiting groove (122) includes a first limiting groove (122a) and a second limiting groove (122b). The first limiting groove (122a) is connected to the installation groove (121) and the second limiting groove (122b) at both ends along the optical axis, respectively. The second limiting groove (122b) extends in a direction perpendicular to the optical axis. The main cylinder (11) is fixed with a limiting member (113) corresponding to the limiting groove (122) on the side near the flange (12). The end of the main cylinder (11) is inserted into the mounting groove (121), the limiting member (113) is inserted into the second limiting groove (122b) through the first limiting groove (122a), the limiting member (113) abuts against the inner wall of the second limiting groove (122b) along the optical axis, and the main cylinder (11) and the flange (12) are fixed along the optical axis by screws.

7. The zoom adapter according to claim 6, characterized in that, The bottom wall of the mounting groove (121) is provided with a plurality of limiting grooves (122) at equal intervals along the circumferential direction, and each of the second limiting grooves (122b) extends along the same circumferential direction; the main cylinder (11) is fixed with a plurality of limiting members (113) corresponding one-to-one with each of the limiting grooves (122) on the end face of the side near the flange (12).

8. The zoom adapter according to claim 6, characterized in that, The flange (12) and the main cylinder (11) are made of a first material, and the screw is made of a second material. The hardness and density of the first material are both less than those of the second material.

9. The zoom adapter according to claim 1, characterized in that, A gasket (13) is also provided between the main cylinder (11) and the flange (12).

10. An endoscope, characterized in that, Includes the zoom adapter as described in any one of claims 1 to 9.

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