Simulation calculation method for lens fastening structure and fastening ring corner
Through simulation analysis model and calculation method of fastening angle, the problem of uneven stress and difficult to quantify the degree of tightening during the lens tightening process is solved, and the uniform stress and tightening degree of lens are quantified, ensuring the high-quality assembly and imaging effect of the lens.
Patent Information
- Application Number
- CN202510327524.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-19
- Publication Date
- 2025-05-16
AI Technical Summary
Uneven force applied to the lens during the tightening process may lead to lens damage and reduced imaging quality. The prior art is difficult to quantify the degree of tightening by relying on the feel.
By creating a three-dimensional geometric model of the lens fastening structure and a simulation analysis model of material properties, the motion characteristics and contact relationship between parts during the fastening process are analyzed, the degree of freedom of the lens holder is constrained, and a gradually increasing remote displacement is applied to the end surface of the fastening ring, and the fastening angle is solved to guide the fastening assembly.
The lens is subjected to uniform stress, avoid lens damage, and ensure the quantification of tightness and the assembling quality.
Smart Images
Figure CN120010082A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of lenses, and in particular to a lens fastening structure and a simulation calculation method for a fastening ring rotation angle. Background Art
[0002] The lens is usually used with the internal thread on the lens mount through the external thread at the end. In order to avoid poor imaging results caused by shaking and misalignment of the lens during testing and work, the more commonly used fixing method is to drill a concave pit at the thread at the end of the lens with the help of multiple prefabricated pin thread holes on the lens mount after the lens has completed focusing and can form a clear image, and tighten the pin into the pit to complete the tightening. This tightening method will cause damage to the lens and because multiple pins cannot be tightened at the same time, the lens may be tilted during the tightening process of a single pin; another commonly used fixing method is to use an open annular clamping plate, and tighten the tightening plate through the bolts set at the opening to complete the tightening. This tightening method will also cause uneven force on the lens, and the lens position may deflect after tightening, affecting the imaging quality. In addition, the tightening degree of the pins and the tightening degree of the bolts in both methods rely more on the feel, and the quality of lens assembly depends on the experience of the operator. Summary of the invention
[0003] The object of the present invention is to provide a lens fastening structure and a method for determining a fastening angle, so as to solve the technical problems that the lens is subjected to uneven force during the fastening process, the lens may be damaged, and the fastening degree cannot be quantified.
[0004] The technical solution for achieving the purpose of the present invention is: a lens fastening structure and a method for determining the fastening angle, creating a simulation analysis model based on the three-dimensional geometric model and material properties of the lens fastening structure, creating a contact relationship based on the movement characteristics of the parts during the fastening process, constraining the 1-6 degrees of freedom of the bottom mounting surface and the fixing hole of the lens holder 1, applying a gradually increasing remote displacement to the end face of the fastening ring 3, and analyzing the deformation and stress of the structure; based on the maximum displacement of the fastening ring 3 when the fastening structure does not undergo material yield deformation, solving the fastening angle to guide the fastening assembly.
[0005] Compared with the prior art, the present invention has the following significant advantages:
[0006] (1) By tightening the fastening ring, the sliders evenly arranged in the radial direction on the lens mount are simultaneously pressed in the radial direction, so that the lens is evenly stressed.
[0007] (2) Based on the characteristics of the lens fastening structure and the properties of the selected materials, and in accordance with the lens fastening structure simulation model, the method of gradually accumulating displacement loading can be used to solve the maximum displacement of the fastening ring along the lens axis when the parts do not undergo plastic deformation. The fastening angle of the fastening ring is calculated to guide the fastening assembly, which can avoid the plastic deformation of the parts caused by human factors during the fastening process and ensure the assembly quality.
[0008] (3) An elastic pressure pad is arranged on the slider to prevent the lens from being damaged when the slider is pressed; the pressure ring is tightened to make the gasket press the slider, and the fastening ring is locked by the pin on the pressure ring, so that the overall locking of the fastening structure can be achieved.
[0009] (4) By properly setting the asymmetric chamfer angle of the fastening ring, the amount of the slider pressed in by the fastening ring can be finely adjusted under the same lead, the contact position between the fastening ring and the slider can be changed, the direction of the pressing force of the fastening ring on the slider can be adjusted, and the axial force on the lens mount during the slider pressing process can be reduced; the lens is mainly subjected to force in the radial direction during the tightening process, and the ring-shaped uniform tightening of the lens can be achieved through the simultaneous action of multiple sliders. BRIEF DESCRIPTION OF THE DRAWINGS
[0010] Figure 1 This is a composition diagram of the lens fastening structure of the present invention, wherein (a) is the main cross-sectional view and (b) is the AA cross-sectional view.
[0011] Figure 2 It is a schematic diagram of a three-dimensional model of the lens fastening structure of the present invention.
[0012] Figure 3 It is a schematic diagram of an enlarged partial cross section of the lens fastening structure of the present invention.
[0013] Figure 4 This is an exploded view of the components of the lens fastening structure of the present invention.
[0014] Figure 5 The present invention is a flowchart for determining the fastening angle of the lens fastening structure.
[0015] Figure 6 Schematic diagram of the contact relationship between the fastening ring 3 and the lens mount 1 of the lens fastening structure of the present invention, wherein (a) is a schematic diagram of the contact surface of the fastening ring 3 of the contact geometry, and (b) is a schematic diagram of the contact surface of the lens mount 1 of the target geometry.
[0016] Figure 7 Schematic diagram of the contact relationship between the slider 4 and the fastening ring 3 of the lens fastening structure of the present invention, wherein (a) is a schematic diagram of the contact surface of the slider 4 of the contact geometry, and (b) is a schematic diagram of the contact surface of the fastening ring 3 of the target geometry.
[0017] Figure 8 Schematic diagram of the contact relationship between the slider 4 and the lens mount 1 of the lens fastening structure of the present invention, wherein (a) is a schematic diagram of the contact surface of the slider 4 of the contact geometry, and (b) is a schematic diagram of the contact surface of the lens mount 1 of the target geometry.
[0018] Fig. 9Schematic diagram of the contact relationship between the slider 4 and the pressure pad 6 of the lens fastening structure of the present invention, wherein (a) is a schematic diagram of the contact surface of the slider 4 of the contact geometry, and (b) is a schematic diagram of the contact surface of the pressure pad 6 of the target geometry.
[0019] Fig.10 Schematic diagram of the contact relationship between the pressure pad 6 and the lens 2 of the lens fastening structure of the present invention, wherein (a) is a schematic diagram of the contact surface of the pressure pad 6 of the contact geometry, and (b) is a schematic diagram of the contact surface of the lens 2 of the target geometry.
[0020] Fig.11 Schematic diagram of the boundary conditions and remote displacement settings of the lens fastening structure of the present invention. Fig.12 This is the corresponding relationship between the distal displacement of the fastening ring 3 and the maximum stress of the fastening structure according to the present invention.
[0021] Fig.13 It is a schematic diagram of the deformation of the lens fastening structure of the present invention in the yield critical state.
[0022] Fig.14 It is a schematic diagram of the stress of the lens fastening structure of the present invention in the yield critical state. DETAILED DESCRIPTION
[0023] To better understand the solution of the present invention, the following Figure 1-14 , the technical solution is described clearly and completely. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments, and cannot be understood as limiting the present invention.
[0024] A lens fastening structure in this embodiment, such as Figure 1 As shown, it includes: a lens mount 1, a lens 2, a fastening ring 3, a slider 4, a pressure ring 5, a pressure pad 6, a gasket 7, and a pin 8.
[0025] The lens 2 and the lens holder 1 are connected via the external thread at the lower part of the lens 2 and the internal thread in the cavity of the lens holder 1; an external thread is provided on the outer surface of the opening for mounting the lens in the lens holder 1, which cooperates with the internal thread on the fastening ring 3; at the same time, circular holes are evenly arranged along the circumference at the lower part of the external thread of the lens holder 1, and the slider 4 is installed in the circular hole on the lens holder 1, and can slide radially along the lens holder 1.
[0026] The surface of the inner side of the tightening ring 3 without threads is tapered and narrow at the top and wide at the bottom, and contacts and cooperates with the hemispherical surface at the end of the slider 4; when the tightening ring 3 is tightened, the tapered surface moves downward to press the slider 4 to slide radially toward the inner side of the circle, and finally the sliders 4 arranged evenly along the circumference and radial direction simultaneously press the lens 2. An elastic pressure pad 6 is provided at the contact portion between the slider 4 and the lens 2.
[0027] An internal thread is provided on the inner surface of the opening of the lens holder 1 for mounting the lens 2, which cooperates with the external thread on the pressing ring 5; an elastic washer 7 is provided at the bottom of the pressing ring 5 in the axial direction, and the washer 7 is tightened to press the slider 4 in the axial direction by tightening the pressing ring 5 to prevent the slider from deflecting in the working environment. The edge of the pressing ring 5 is provided with a plurality of threaded holes evenly distributed along the circumference, and the pin 8 is screwed into the threaded hole to press the fastening ring 3, completing the overall locking of the fastening structure.
[0028] Lens mount 1 and lens 2 are made of 2A12-T4 aluminum alloy with a yield strength of 255Mpa;
[0029] The fastening ring 3, the pressure ring 5 and the slider 4 are made of 65# spring steel with a yield strength of 785MPa;
[0030] The pressure pad 6 and the washer 7 are made of an elastomeric material, with a Young's modulus of 4000 MPa and a Poisson's ratio of 0.2; the pin is made of a structural steel material.
[0031] The threads that cooperate with the lens mount 1, the pressure ring 5 and the fastening ring 3 are all fine threads with a pitch of 1 mm.
[0032] The circular holes on the lens holder 1 for placing the slider 4 are distributed in a circular symmetrical manner, with a number of 24, and the interval angle between the center lines of adjacent circular holes is 15 degrees.
[0033] The conical surface on the lower side of the internal thread of the fastening ring 3 is generated by asymmetric offset chamfering of the lower end circular edge in UG. The offset 1 is 5 mm axially upward along the fastening ring, and the offset 2 is 1 mm radially outward along the fastening ring. The compression amount of the slider 4 under the same lead can be adjusted by setting different offset sizes.
[0034] The outer edge of the fastening ring 3 is evenly provided with trapezoidal grooves, which can increase the surface friction and facilitate the tightening operation of the fastening ring 3. Other chamfer angles are set according to C0.5.
[0035] The slider 4 includes a cylindrical body section and a square body section. The cylindrical body section and the opening on the lens holder 1 are matched with a small gap, and the end face of the cylindrical body section is spherical and contacts the conical surface of the fastening ring 3;
[0036] As an implementation of this embodiment, 24 sliders are evenly arranged in the circular hole of the lens holder 1, and the end faces of the square body segments of the sliders form cylindrical holes, so that the cylindrical surface radius of the end face of each square body segment is 1 mm greater than the radius of the lens.
[0037] The inner diameter of the pressing ring 5 is 1 mm larger than the diameter of the lens; the outer diameter of the pressing ring 5 is the same as the outer diameter of the fastening ring 3. Four threaded holes are evenly arranged at the contact position between the edge of the pressing ring 5 and the fastening ring 3 for installing pins.
[0038] The inner conical surface of the pressing ring 5 is generated by asymmetric offset chamfering of the upper circular edge in UG, with offset 1 being 7 mm outward along the radial direction of the pressing ring and offset 2 being 2.5 mm upward along the axial direction of the pressing ring. Other chamfers are set according to C0.5.
[0039] The pressure pad is consistent in size with the cylindrical surface of the slider 4 and is bonded together. The thickness can be adjusted according to the length of the slider 4 and is set to 1 mm in the embodiment.
[0040] The washer and the pressure ring 5 have the same end size and are bonded together. In the embodiment, the thickness is set to 1 mm.
[0041] Pins are standard parts.
[0042] Combination Figure 4 The assembly sequence of the lens fastening structure in this embodiment is as follows: place the lens mount 1 with the lens mounting port facing upward, and insert the slider 4 with a pressure pad in the circular hole in turn; after the slider 4 is placed, screw the fastening ring 3 and do not tighten it temporarily; after the lens 2 is inserted into the pressure ring 5 with a pressure pad, it is assembled to the lens mount 1 through threads, and after the lens 2 adjusts the focal length, the fastening ring 3 is gradually screwed in so that the pressure pad fits the cylindrical surface of the lens 2. According to the rotation angle of the fastening ring 3 (i.e., the fastening ring rotation angle T1) (i.e., the maximum rotation angle of the fastening ring 3) solved by the simulation, the fastening ring 3 is gradually screwed in, and the change in the imaging quality is observed at the same time. If the imaging quality begins to change before rotating to the tightening angle, the tightening action is stopped, otherwise it is continuously tightened to the tightening angle; next, the pressure ring 5 is tightened to tighten the slider 4, and the pins arranged on the pressure ring 5 are tightened to lock the fastening ring 3, thereby completing the overall locking of the fastening structure.
[0043] This embodiment also discloses a simulation calculation method for the fastening angle of a lens fastening structure. The specific process based on ANSYS simulation software is as follows: Figure 5 shown.
[0044] S1: Complete geometry cleaning and material setting based on the 3D model of the lens fastening structure and selected materials.
[0045] S2: Setting contact relationship. A non-separation contact relationship is set between the fastening ring 3 and the lens holder 1, a friction contact relationship is set between the slider 4 and the fastening ring 3; a non-separation contact relationship is set between the slider 4 and the lens holder 1; a binding contact relationship is set between the slider 4 and the pressure pad 6; a friction contact relationship is set between the pressure pad 6 and the lens 2, such as Figure 6-10 shown.
[0046] S3: Set boundary conditions and remote displacement. Constrain the 1-6 degrees of freedom of the bottom mounting surface and the fixing hole of the lens holder 1, set a gradually increasing remote displacement on the end surface of the fastening ring 3 along the direction of the lens screwing in, and the displacement loading step length d0 = 0.01mm. According to the remote displacement applied in the i-th analysis step, d i=i×d0, solve and output the maximum stress of the jth part of the model under the i-th analysis step, such as the maximum stress S of each part ij Not greater than the yield strength S of the selected material j屈服 , then continue to accumulate displacement d0 to solve the next step; if the maximum stress S of each part ij Greater than the yield strength S of the selected material j屈服 , then the remote displacement d applied in the previous step is output i-1 The corresponding relationship between the distal displacement of the fastening ring 3 and the maximum stress of the fastening structure is as follows: Fig.12 As shown, the stress of the lens fastening structure increases sharply with the gradual increase of the distal displacement of the fastening ring 3.
[0047] S4: According to the remote displacement d i-1 Calculate the rotation angle T1 of the fastening circle, T1 = d i-1 ×360 / P, where P is the pitch. Considering the possible change in imaging quality caused by optical path deviation under low stress during lens fastening, the measured rotation angle T0 of the fastening ring when the imaging quality changes is compared with T1. If T1 is less than or equal to T0, T1 is used as the fastening ring rotation angle to guide assembly, otherwise T0 is used as the fastening rotation angle to guide assembly.
[0048] In this embodiment, the yield stress of the material selected for the slider 4 is 785 MPa; when the distal end displacement of the fastening ring 3 is 0.18 mm, the slider 4 is at the critical point of yield stress, and the deformation and stress of the lens fastening structure at this time are evaluated, such as Fig.13 , Fig.14 From the deformation and stress cloud diagram of the lens fastening structure in the yield critical state, it can be found that when the fastening ring 3 is loaded with a distal displacement of 0.18 mm along the axial direction, the slider 4 simultaneously presses the lens 2 inward through the pressure pad 6 along the radial direction of the lens holder 1; the deformation of the lens 2 along the radial direction is uniform; the maximum structural stress occurs at the contact position between the spherical surface of the slider 4 and the fastening ring 3; when the slider 4 is in the yield stress critical state, the lens 2 is subjected to uniform force along the radial direction.
[0049] Based on the simulation results, the tightening angle T1 = 0.18 × 360 / 1 = 64.8 degrees is solved.
[0050] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention without departing from the principles and intent of the present invention.
Claims
1. A lens fastening structure, characterized in that: The invention comprises a lens seat (1), a lens (2), a fastening ring (3), a sliding block (4), and a pressing ring (5); the lens (2) and the lens seat (1) are connected via an external thread at the lower part of the lens (2) and an internal thread in the cavity of the lens seat (1); an external thread is arranged on the outer surface of an opening at which the lens is installed on the lens seat (1), and the external thread cooperates with the internal thread on the fastening ring (3); at the same time, circular holes are evenly arranged along the circumference at the lower part of the external thread of the lens seat (1); the sliding block (4) is installed in the circular hole on the lens seat (1) and slides along the radial direction of the lens seat (1); an internal thread is arranged on the inner surface of the opening at which the lens (2) is installed on the lens seat (1), and the internal thread cooperates with the external thread on the pressing ring (5).
2. The lens fastening structure according to claim 1, characterized in that: The lens fastening structure also includes a pressure pad (6), which is arranged at the contact position between the slider (4) and the lens (2) and is used to compensate for the gap through deformation of the pressure pad (6), increase the contact area, disperse the pressure, and prevent the slider (4) from crushing the lens (2).
3. The lens fastening structure according to claim 1, characterized in that: The lens fastening structure also includes a gasket (7); an elastic gasket (7) is arranged at the bottom of the pressure ring (5) in the axial direction, and the gasket (7) is pressed against the slider (4) in the axial direction by tightening the pressure ring (5) to prevent the slider from deflecting in a working environment.
4. The lens fastening structure according to claim 1, characterized in that: The lens fastening structure also includes a pin (8). The edge of the pressure ring (5) is provided with a plurality of threaded holes evenly distributed along the circumference. The pin (8) is screwed into the threaded hole to press the fastening ring (3), thereby completing the overall locking of the fastening structure.
5. The lens fastening structure according to claim 1, characterized in that: The outer edge of the fastening ring (3) is evenly provided with trapezoidal grooves for increasing surface friction.
6. The lens fastening structure according to claim 1, characterized in that: The chamfer angles of the conical surface on the lower side of the internal thread of the fastening ring (3) are: the right angle side along the axial direction of the fastening ring is 5 mm, and the right angle side along the radial direction of the fastening ring is 1 mm.
7. The lens fastening structure according to claim 1, characterized in that: The chamfer angles of the inner conical surface of the pressing ring (5) are as follows: the right angle side along the radial direction of the pressing ring is 7 mm, and the right angle side along the axial direction of the pressing ring is 2.5 mm.
8. A simulation calculation method for the rotation angle of a fastening ring of a lens fastening structure, characterized in that: The lens fastening structure applicable to any one of claims 1 to 7 comprises the following specific steps: S1: Complete geometry cleaning and material setting based on the 3D model of the lens fastening structure and selected materials; S2: a contact relationship is set, a non-separation contact relationship is set between the fastening ring (3) and the lens holder (1), a friction contact relationship is set between the slider (4) and the fastening ring (3); a non-separation contact relationship is set between the slider (4) and the lens holder (1); a binding contact relationship is set between the slider (4) and the pressure pad (6); and a friction contact relationship is set between the pressure pad (6) and the lens (2); S3: setting boundary conditions and remote displacement; constraining the degrees of freedom of the mounting surface and the fixing hole at the bottom of the lens holder 1, setting a gradually increasing remote displacement on the end surface of the fastening ring 3 along the direction of lens screwing in, and solving and outputting the maximum stress of the jth part of the model under the i-th analysis step according to the remote displacement applied in the i-th analysis step; If the maximum stress S of each part ij Not greater than the yield strength S of the selected material j屈服 , then continue to accumulate displacement d0 to proceed to the next step of solution; if the maximum stress S of each part ij Greater than the yield strength S of the selected material j屈服 , then the remote displacement d applied in the previous step is output i-1 ; S4: Calculate the rotation angle of the fastening circle based on the remote displacement.
9. The simulation calculation method for the rotation angle of the fastening ring of the lens fastening structure according to claim 8, characterized in that: In S4, the calculation formula of the fastening circle angle is: T1=d i-1 ×360 / P, Where T1 is the rotation angle of the fastening circle and P is the thread pitch.
10. The simulation calculation method for the rotation angle of the fastening ring of the lens fastening structure according to claim 9, characterized in that: The measured rotation angle T0 of the fastening ring when the imaging quality changes is compared with the fastening ring rotation angle T1. If T1 is less than or equal to T0, the fastening ring rotation angle T1 is used as the fastening ring rotation angle to guide assembly; otherwise, the measured rotation angle T0 of the fastening ring is used as the fastening ring rotation angle to guide assembly.