Lens clamping mechanism for optical coating device

Abstract

The invention discloses a lens clamping mechanism for an optical coating device. A lens clamping mechanism for an optical coating device is characterized in that an optical lens is fixed on a lens seat, the optical lens and the lens seat form a lens group, and the lens group is connected with the upper surface of a planetary plate through flexible pieces arranged in the circumferential direction; the flexible part is a cylinder, at least two force buffering grooves distributed from top to bottom are formed in the cylinder, and the circumferential interval angle of every two adjacent force buffering grooves is not larger than 180 degrees. The flexible part counteracts force generated by thermal expansion of the planetary plate through self deformation, the situation that the deformation of the planetary plate is conducted to the lens base and influences the coating precision of the optical lens is avoided, and therefore the purpose of improving the surface type of the optical lens is achieved. Meanwhile, by optimizing the effective shearing sectional area and the shearing action length of the flexible part structure, the anti-shearing strength is reduced, and meanwhile the situation that the shearing stress is too large is avoided.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of machinery, in particular to a lens clamping mechanism. BACKGROUND

[0002] Optical coating refers to depositing a layer (or multiple layers) of thin film on the surface of optical parts in a vacuum state by evaporation deposition to improve its optical performance. With the increasing performance requirements of optical equipment, the precision requirements of optical coating are also increasing. Therefore, higher requirements are put forward for the clamping device of optical lenses during the coating process.

[0003] The previous coating clamping mechanism is as shown below Figure 1 The optical lens is fixed in the lens seat to form a lens group, the lens group is fixedly connected with the planet disc through the evenly distributed screws along the circumference, and the planet disc is fixed radially in the vacuum coating cavity to complete the uniform coating of the optical lens by rotating at a low speed around the main shaft.

[0004] The previous coating clamping mechanism generates a large clamping stress on the lens, especially during the coating process, the temperature can reach 300℃ or even higher. Due to the temperature rising to 300℃ during the coating process, the outer cylindrical surface of the planet disc is constrained and expands inwardly under the heat, while the inner cylindrical surface of the lens seat expands outwardly under the heat due to the size limitation of the lens, and the two opposite deformations cause a large shear stress at the connecting bolt, which affects the stability of the structure on the one hand, and the shear stress also acts on the lens seat in the opposite direction and is conducted to the optical lens, causing the lens to deform, the coating performance to deteriorate, and the optical lens to be damaged and broken, causing serious economic losses.

[0005] Therefore, the present application proposes a new clamping mechanism, which reduces the transmission of clamping stress and the influence of the deformation of the clamping mechanism on the lens surface during the high-temperature coating process, and improves the coating yield and yield. SUMMARY

[0006] The present application provides a lens clamping mechanism for an optical coating device to solve at least one of the above technical problems.

[0007] A lens clamping mechanism for an optical coating device, comprising an optical lens fixed on a lens seat, the optical lens and the lens seat forming a lens group, characterized in that the lens group is connected with the upper surface of a planet disc through circumferentially arranged flexible members.

[0008] The flexible member is a cylindrical body, at least two force cushion grooves are arranged from top to bottom on the cylindrical body, and the circumferential interval angle of adjacent force cushion grooves is not greater than 180°.

[0009] Further preferably, the cylindrical body is provided with an upper perforation for inserting an upper pin and a lower perforation for inserting a lower pin.

[0010] The top of the cylinder is provided with an upper fastening hole for connecting the upper through hole, the upper fastening hole is threaded connected with an upper fastening screw, and the upper fastening screw is in abutment with the upper pin;

[0011] The bottom of the cylinder is provided with a lower fastening hole for connecting the lower through hole, the lower fastening hole is threaded connected with a lower fastening screw, and the lower fastening screw is in abutment with the lower pin.

[0012] Further preferably, the force buffering groove is located in a region between the region for installing the upper pin and the region of the lower pin on the cylinder.

[0013] Further preferably, the top of the upper pin is beyond the top surface of the cylinder;

[0014] The bottom of the lower pin is beyond the bottom surface of the cylinder;

[0015] The outer edge of the mirror seat is provided with an upper insertion hole for longitudinally inserting the region of the upper pin beyond the top surface of the cylinder;

[0016] The inner side region of the planet disc is provided with a lower insertion hole for longitudinally inserting the region of the lower pin beyond the bottom surface of the cylinder.

[0017] Further preferably, the upper through hole and the lower through hole are connected through the cylinder.

[0018] Further preferably, two groups of upper and lower groove groups are provided on the cylinder;

[0019] Each group of groove groups is provided with at least two force buffering grooves arranged in a staggered manner.

[0020] Further preferably, each group of groove groups is provided with four force buffering grooves;

[0021] Two adjacent buffering grooves in the four force buffering grooves form a buffering unit, and the circumferential interval angle of the two force buffering grooves in the same buffering unit is 180°;

[0022] The interval angle of the adjacent force buffering grooves in two adjacent buffering units is 90°.

[0023] Further preferably, the force buffering groove, the upper through hole and the lower through hole are connected.

[0024] Further preferably, the material of the planet disc and the mirror seat is aluminum alloy.

[0025] Further preferably, the material of the flexible member is aluminum alloy, stainless steel or copper.

[0026] Further preferably, the cross-sectional profile structure of the force buffer groove is sequentially connected with a convex arc and a straight line segment;

[0027] The central angle of the convex arc is greater than 180°.

[0028] The circumferential interval angle of the vertical projection of the straight line segment of the adjacent force buffer groove is the circumferential interval angle of the adjacent force buffer groove.

[0029] Beneficial effects:

[0030] The flexible member of the present application offsets the force generated by the thermal expansion of the planet disc through its own deformation, avoids the deformation of the planet disc from being transmitted to the mirror seat, and affects the coating precision of the optical lens, thereby achieving the purpose of improving the surface shape of the optical lens.

[0031] At the same time, the flexible member structure optimizes the effective shear section area and the shear action length, reduces the shear strength, and avoids excessive shear stress. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1 A structural schematic diagram for background technology;

[0033] Figure 2 A structural schematic diagram of embodiment 1 of the present application;

[0034] Figure 3 A structural schematic diagram of embodiment 1 of the present application from another perspective;

[0035] Figure 4 A local structural schematic diagram of embodiment 1 of the present application;

[0036] Figure 5 A half-sectional view of the flexible member of embodiment 1 of the present application;

[0037] Figure 6 A structural schematic diagram of the flexible member of embodiment 1 of the present application;

[0038] Figure 7 A local structural schematic diagram of the flexible member of embodiment 1 of the present application;

[0039] Figure 8 A local sectional view of embodiment 1 of the present application;

[0040] Figure 9 A comparison schematic diagram of simulation verification results of embodiment 1 of the present application.

[0041] In the figure: 1 is an optical lens, 2 is a mirror seat, 3 is a flexible member, 4 is a planet disc, 5 is an upper pin, and 6 is a lower pin. DETAILED DESCRIPTION

[0042] With reference to the drawings of the embodiments of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments of the present application, all the other embodiments obtained by those skilled in the art without creative work fall within the scope of the present application.

[0043] Please refer to Figures 1 to 9 As shown in the specific embodiment 1, a lens clamping mechanism for optical coating device includes an optical lens 1 fixed on a lens seat 2, the optical lens 1 and the lens seat 2 form a lens group, the lens group is connected with the upper surface of a planet disk 4 through a circumferential arrangement of flexible members 3; the flexible member 3 is a cylinder, at least two force buffer grooves 31 arranged from top to bottom are formed on the cylinder, and the circumferential interval angle of adjacent force buffer grooves 31 is not greater than 180°.

[0044] The cylinder is provided with an upper through hole for inserting an upper pin 5 and a lower through hole for inserting a lower pin 6; the top of the cylinder is provided with an upper fastening hole for connecting the upper through hole, the upper fastening hole is threadedly connected with an upper fastening screw, and the upper fastening screw is in abutment with the upper pin 5; the bottom of the cylinder is provided with a lower fastening hole for connecting the lower through hole, the lower fastening hole is threadedly connected with a lower fastening screw, and the lower fastening screw is in abutment with the lower pin 6.

[0045] The force buffer groove 31 is located in the region between the region for installing the upper pin 5 and the region for installing the lower pin 6 on the cylinder.

[0046] The top of the upper pin 5 exceeds the top surface of the cylinder; the bottom of the lower pin 6 exceeds the bottom surface of the cylinder; the outer edge of the lens seat 2 is provided with an upper insertion hole for longitudinally inserting the region of the upper pin 5 exceeding the top surface of the cylinder; the inner side region of the planet disk 4 is provided with a lower insertion hole for longitudinally inserting the region of the lower pin 6 exceeding the bottom surface of the cylinder.

[0047] The upper through hole and the lower through hole are vertically connected through the cylinder. The force buffer groove is in communication with the upper through hole and the lower through hole.

[0048] Two groups of upper and lower groove groups are formed on the cylinder; each group of groove groups is provided with at least two force buffer grooves arranged in a staggered manner. Each group of groove groups is provided with four force buffer grooves; two adjacent buffer grooves in the four force buffer grooves form a buffer unit, the circumferential interval angle of the two force buffer grooves in the same buffer unit is 180°; the interval angle of the adjacent force buffer grooves in the two adjacent buffer units is 90°.

[0049] The force buffer groove, the upper through hole and the lower through hole are in communication with each other.

[0050] The materials of the planet disk 4 and the lens seat 2 are aluminum alloy.

[0051] The flexible component 3 is made of aluminum alloy, stainless steel, or copper.

[0052] The cross-sectional profile of the force buffer groove consists of sequentially connected major arcs and straight line segments; the central angle of the major arc is greater than 180°; the circumferential interval angle between adjacent force buffer grooves is the angle of the vertical projection of the straight line segments of the adjacent force buffer grooves.

[0053] When the planetary disk and mirror mount are made of aluminum alloy, the relationship between the coefficient of linear expansion α and temperature is α(T) = 22.5 + 0.012T + 0.0001T 2 (Unit x 10) -6 The elastic modulus E is 71 GPa. When the room temperature rises from 22℃ to 300℃, the temperature rise ΔT = 278℃. The planetary disk and mirror mount structure are simplified as a ring for theoretical analysis: the outer cylindrical surface of the planetary disk is fixed, the width of the planetary disk ring is L1, and the thickness is H1. The force generated after thermal expansion is F1 = E*α*ΔT*A1 = E*α*ΔT*L1*H1 (A1 is the cross-sectional area); when the inner cylindrical surface of the mirror mount is fixed and constrained, the width of the mirror mount ring is L2, and the thickness is H2. The force generated after thermal expansion is F2 = E*α*ΔT*A2 = E*α*ΔT*L2*H2 (A2 is the cross-sectional area).

[0054] The thermal expansion amounts of the planetary disk and the mirror mount are ΔX1 and ΔX2, respectively, in opposite directions. Consequently, the resulting forces F1 and F2 are also in opposite directions. Figure 8 As shown.

[0055] Therefore, when the mirror mount and the planetary disk are connected by a flexible component, the flexible component needs to offset the force generated by the thermal expansion of the planetary disk through its own deformation to prevent the deformation of the planetary disk from being transmitted to the mirror mount and affecting the coating accuracy of the optical lens; at the same time, the shear stress on the flexible component must be within the allowable stress range of the material to prevent plastic deformation.

[0056] Therefore, it is necessary to reduce the shear strength of the connector Ks=GA / L (G is the material shear modulus, A is the effective shear cross-sectional area, and L is the shear action length) while satisfying the shear stress τ=abs(F1-F2) / A<τs[allowable shear strength].

[0057] See Figure 9 Simulation results demonstrate that this coating clamping mechanism can provide flexible support for optical lens assemblies during high-temperature (300℃ or higher) coating processes, reducing the transmission of clamping stress caused by high-temperature deformation to the optical lenses. This improves lens surface shape and increases coating yield and productivity. Furthermore, this coating clamping device is highly versatile. By combining finite element analysis tools with optimized stiffness and optimized placement and quantity of flexible components, it can provide flexible support for lenses of different sizes and weights, thereby achieving the goal of improving coating yield and productivity.

[0058] It will be apparent to those skilled in the art that the application is not limited to the details of the above-exemplified embodiments and that the present application can be implemented in other particular forms without departing from the spirit or essential characteristics of the present application. The presently disclosed embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, the scope of the application being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. No feature of the application is to be construed as limiting the scope of the claims to the instant embodiment.

[0059] Furthermore, it should be understood that although the description above refers to particular embodiments, the description is illustrative only and is not intended to limit the claimed application in any way. The various embodiments set forth herein are not mutually exclusive, but can be combinable in other embodiments, as can be understood by those skilled in the art upon reading the present disclosure.

Claims

1. A lens clamping mechanism for an optical coating device, comprising an optical lens fixed on a lens holder, the optical lens and the lens holder constituting a lens set, characterized in that, The mirror group is connected with the upper surface of the planet disc through the circumferential flexible member; The flexible member is a cylinder, and at least two force buffering grooves are arranged from top to bottom on the cylinder, and the circumferential interval angle of adjacent force buffering grooves is not greater than 180°.

2. The lens holding mechanism for an optical coating apparatus according to claim 1, wherein: Upper and lower through holes for inserting the upper and lower pins are arranged on the cylinder; An upper fastening hole for connecting the upper through hole is arranged at the top of the cylinder, and the upper fastening hole is threadedly connected with an upper fastening screw, and the upper fastening screw is in abutment with the upper pin; A lower fastening hole for connecting the lower through hole is arranged at the bottom of the cylinder, and the lower fastening hole is threadedly connected with a lower fastening screw, and the lower fastening screw is in abutment with the lower pin.

3. The lens holding mechanism for an optical coating apparatus according to claim 2, wherein: The force buffering grooves are arranged between the area for installing the upper pin and the area for installing the lower pin on the cylinder.

4. The lens holding mechanism for an optical coating apparatus according to claim 2, wherein: The top of the upper pin is beyond the top surface of the cylinder; The bottom of the lower pin is beyond the bottom surface of the cylinder; An upper insertion hole for longitudinally inserting the area of the upper pin beyond the top surface of the cylinder is arranged on the outer edge of the mirror seat; A lower insertion hole for longitudinally inserting the area of the lower pin beyond the bottom surface of the cylinder is arranged on the inner side of the planet disc.

5. The lens holding mechanism for an optical coating apparatus according to claim 2, wherein: The upper and lower through holes are connected through the cylinder.

6. The lens holding mechanism for an optical coating device according to claim 1, wherein: Two groups of upper and lower groove groups are arranged on the cylinder; Each group of groove groups is provided with at least two force buffering grooves arranged in a staggered manner.

7. The lens holding mechanism for an optical coating apparatus according to claim 6, wherein: Each group of groove groups is provided with four force buffering grooves. Two adjacent buffering grooves in the four force buffering grooves form a buffering unit, and the circumferential interval angle of the two force buffering grooves in the same buffering unit is 180°. The interval angle of adjacent force buffering grooves in adjacent buffering units is 90°.

8. The lens holding mechanism for an optical coating device according to claim 2, wherein: The force buffering grooves, the upper through hole and the lower through hole are connected in a penetrating manner.

9. The lens holding mechanism for an optical coating device according to claim 1, wherein: The planet disc and the mirror seat are made of aluminum alloy. The flexible member is made of aluminum alloy, stainless steel or copper.

10. The lens holding mechanism for an optical coating apparatus according to claim 1, wherein: The cross-sectional profile structure of the force buffering groove is sequentially connected with an optimal arc and a straight line segment. The central angle of the optimal arc is greater than 180°. The circumferential interval angle of the vertical projection of the straight line segment of adjacent force buffering grooves is the circumferential interval angle of the adjacent force buffering grooves.

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