Lens thermal shrinkage fixing device and fixing method

Abstract

The invention relates to a lens thermal shrinkage fixing device and method, and belongs to the technical field of optical lens fixing.The lens thermal shrinkage fixing device comprises a lens frame, a lens thermal shrinkage fixing device and a lens thermal shrinkage fixing device, and the locking ring is made of a thermal shrinkage material and sleeves the periphery of the lens, the edge of the locking ring is provided with a buckle embedded into the clamping groove, and the buckle is clamped with the clamping groove after thermal shrinkage heating. The technical problems that in the prior art, the occupied space is large, and the installation and adjustment difficulty is high can be solved.

Description

Technical Field

[0001] The invention belongs to the technical field of optical lens fixing, and in particular relates to a lens heat shrink fixing device and a fixing method. Background Art

[0002] Lens installation is to stably fix the lens to the frame and give the lens a continuous tightening force to prevent the lens from shifting during operation. During the installation process, the relative position relationship between the lens and the frame needs to be adjusted to meet the optical design indicators.

[0003] For lenses or reflectors with small diameters (hereinafter collectively referred to as "lenses"), common fixing methods include press ring fixing and glue injection fixing. Among them, the press ring fixing method is to first install the lens on the frame, and control the axis position of the lens through the clearance fit tolerance of the structure. The press ring types include threaded press rings and flange press rings. Threaded press rings are press rings with threads that press the lens tightly, such as Figure 1 As shown in the figure, after the threaded clamp and the mirror surface are partially in contact, it is usually necessary to continue tightening to achieve the compression of the lens. In the process of continuing to tighten, the friction between the threaded clamp and the mirror surface will cause damage to the mirror surface (coating). In addition, in order to improve stability, the axial length of the thread of the threaded clamp and the frame should be no less than 3 times the pitch, which occupies a large axial space. The flange clamp presses the lens by tightening the flange with screws, such as Figure 2 As shown in the figure, since some auxiliary screws (usually 3) are needed to connect the flange and the mirror frame, a large space is occupied in both the axial and circumferential directions. Since the hardness of metal is usually large, it is difficult to deform greatly under a small pressure. In order to achieve surface contact between the pressure ring and the mirror surface, a plastic gasket is usually placed between the pressure ring and the mirror surface. The pressure ring adjusts the clamping force on the mirror surface by controlling the tightening torque of the thread during assembly, which can only be achieved through process inspection during assembly inspection, which is relatively costly.

[0004] The glue-filling fixing method is to place the lens in place, squeeze the adhesive into the flow channel through the glue injection hole on the side of the frame, and after the glue solidifies, glue the lens to the frame. Figure 3 As shown. Due to the existence of the glue injection hole, it is generally difficult to directly control the axis position and angle of the lens through structural tolerances. Manual adjustment is usually required, which increases the difficulty of installation and adjustment. At the same time, some glue is volatile and will affect the light near the mirror surface. Summary of the invention

[0005] In view of various deficiencies in the prior art, a lens heat shrink fixing device and fixing method are proposed to solve the technical problems of the prior art that the device occupies a large space and is difficult to install and adjust.

[0006] To achieve the above object, the present invention provides the following technical solutions: In a first aspect, the present invention provides a lens heat shrink fixing device, comprising: The frame has a mounting cavity for mounting the lens and a slot at the edge thereof; The locking ring is made of heat shrinkable material and is sleeved on the periphery of the lens. A buckle embedded in the slot is provided on the edge of the locking ring. After heat shrinkage and heating, the buckle is engaged with the slot.

[0007] The technical solution is further configured that the first side edge of the frame is provided with a plurality of latching protrusions extending toward the axis direction thereof, adjacent latching protrusions are arranged at intervals to form the latching groove, and a plug hole is provided inside the latching protrusion.

[0008] The technical solution is further configured such that the outer contour size of the locking ring is smaller than the size of the pattern enclosed by the jack.

[0009] The technical solution is further configured such that the first side edge of the locking ring is provided with buckles extending first away from the main body and then away from the axis, and the number of the buckles is not more than the number of the slots.

[0010] The technical solution is further configured that the second side edge of the locking ring extends toward the axis direction thereof to form a limiting ring, the lens is located between the limiting ring and the clamping protrusion, and the inner diameter of the limiting ring is smaller than the diameter of the lens; A first contact surface is formed between the mirror surface on one side of the lens and the limiting ring, a second contact surface is formed between the mirror surface on the other side of the lens and the clamping protrusion, and a third contact surface is formed between the buckle and the clamping groove after heat shrinkage and heating.

[0011] The technical solution is further configured such that the first contact surface is located between two side surfaces of the frame, and the third contact surface is located between two side mirror surfaces of the lens.

[0012] In a second aspect, the present invention provides a method for fixing a lens by heat shrinkage, comprising the following steps: S100, expanding the locking ring in its radial direction, stretching the buckle in its axial direction, and sleeve-arranging the expanded locking ring around the periphery of the lens until a first contact surface is formed between a mirror surface on one side of the lens and the locking ring; S200, inserting the stretched buckle into the card slot, and assembling the lens into the mounting cavity until a second contact surface is formed between the other side of the lens and the frame; S300, heat and shrink the frame, the lens and the locking ring until the buckle and the slot are engaged to form a third contact surface, and the lens is fixed by heat shrinking.

[0013] The technical solution is further configured such that, in step S100, the axial distance between the first contact surface and the buckle after stretching is greater than the thickness of the lens.

[0014] The technical solution is further configured such that, in step S300, the heat shrinking heating temperature is higher than the normal use temperature of the lens, and the heat shrinking heating temperature is lower than the normal use temperature of the lens coating layer.

[0015] The technical solution is further configured as follows: the locking ring is made of polytetrafluoroethylene, the heat shrinkage heating temperature is 100°C to 250°C, and the insulation time is 8min to 25min.

[0016] The beneficial effects of the present invention are: The locking ring is made of heat-shrinkable material. Before assembly, the axial and radial dimensions of the locking ring are small, which is suitable for narrow spaces. During assembly, the locking ring is radially expanded and the buckle is stretched axially. The lens is wrapped in soft heat-shrinkable material and will not be scratched. The locking ring, after heat shrinkage and heating, fits tightly with the lens and frame, effectively ensuring the axial and radial support stiffness of the lens. The axial position of the lens is guaranteed by the matching tolerance between the mounting cavity and the cylindrical surface of the lens, reducing the difficulty of lens installation and adjustment. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of a lens fixing method using a threaded pressure ring in the prior art; Figure 2 It is a schematic diagram of a lens fixed by a flange pressure ring in the prior art; Figure 3 It is a schematic diagram of the lens fixing method using glue filling in the prior art; Figure 4 is an isometric view of a lens heat shrink fixing device according to an embodiment of the present invention; Figure 5 It is a front view of the lens heat shrink fixing device in an embodiment of the present invention; Figure 6 for Figure 5 Middle AA section view; Figure 7 for Figure 6 Partial schematic diagram at C in the middle; Figure 8 It is a front view of the locking ring in the embodiment of the present invention; Fig. 9 is a side view of a locking ring in an embodiment of the present invention; Fig.10 is a front view of a frame in an embodiment of the present invention; Fig.11 for Fig.10 Middle BB section view; Fig.12A cross-sectional view of another embodiment of the lens heat shrink fixing device in an embodiment of the present invention; Fig.13 is a flowchart of a method for heat shrinking and fixing a lens in an embodiment of the present invention; In the attached drawings: 1, frame; 2, cam; 3, locking ring; 4, buckle; 5, lens; 7, limit ring; 8, first contact surface; 9, second contact surface; 10, third contact surface; 11, mounting cavity; 12, slot; 13, jack; 14, threaded hole. DETAILED DESCRIPTION

[0018] In order to enable those skilled in the art to better understand the technical solution of the present invention, the technical solution of the present invention is clearly and completely described below in conjunction with the accompanying drawings of the present invention. Based on the embodiments in this application, other similar embodiments obtained by ordinary technicians in this field without making creative work should all fall within the scope of protection of this application. In addition, the directional words mentioned in the following embodiments, such as "up", "down", "left", "right", etc., are only reference to the directions of the accompanying drawings. Therefore, the directional words used are used to illustrate rather than limit the invention.

[0019] According to an embodiment of the present invention, a lens heat shrink fixing device is provided. Figures 4 to 11 ,include: The frame 1 has a mounting cavity 11 for mounting the lens 5, and a slot 12 is provided at its edge; The locking ring 3 is made of heat shrinkable material and is sleeved on the periphery of the lens 5. A buckle 4 embedded in the slot 12 is provided on the edge of the locking ring 3. After heat shrinkage and heating, the buckle 4 is engaged with the slot 12.

[0020] It should be noted that the locking ring 3 is made of heat-shrinkable material, and the lens 5 is fixed by utilizing its heat-shrinking property, that is, the characteristic of restoring to the original structural state at a relatively high temperature; the axial and radial dimensions of the locking ring 3 before assembly are relatively small, and it is suitable for narrow spaces; during assembly, the locking ring 3 is radially stretched and the buckle 4 is axially stretched, and the lens 5 is wrapped by the soft heat-shrinkable material without causing scratches; the locking ring 3 after heat shrinkage and heating fits tightly with the lens 5 and the frame 1, effectively ensuring the axial and radial support stiffness of the lens 5; the axial position of the lens 5 is guaranteed by the fitting tolerance between the mounting cavity 11 and the cylindrical surface of the lens, reducing the difficulty of installing and adjusting the lens 5.

[0021] In the lens heat shrink fixing device of this embodiment, please refer to Figures 4 to 11 The first side edge of the frame 1 is provided with a plurality of latching protrusions 2 extending toward the axial direction thereof, and adjacent latching protrusions 2 are arranged at intervals to form the latching slot 12 , and a plug hole 13 is provided inside the latching protrusion 2 .

[0022] It should be noted that a plurality of latching protrusions 2 are evenly distributed along the first side edge of the frame 1 to improve the assembly stability of the frame 1, the locking ring 3 and the lens 5; no latching protrusion 2 is provided on the second side edge of the frame 1 to facilitate smooth assembly of the locking ring 3 and the lens 5.

[0023] Specifically, the clamping protrusion 2 includes a connecting portion and a limiting portion, wherein the connecting portion is perpendicular to the first side edge of the frame 1, and the limiting portion extends from the connecting portion to the direction close to the axis of the frame 1, and at the same time, the thickness of the limiting portion gradually changes along the direction from the connecting portion to the direction close to the axis of the frame 1 to match the longitudinal cross-sectional shape of the lens 5. If the lens 5 is a convex lens, the thickness of the limiting portion gradually decreases along the direction from the connecting portion to the direction close to the axis of the frame 1.

[0024] In the lens heat shrink fixing device of this embodiment, please refer to Figures 4 to 11 The outer contour size of the locking ring 3 is smaller than the size of the pattern surrounded by the insertion hole 13.

[0025] Preferably, the shape of the pattern formed by the plurality of jacks 13 is the same as the outer contour of the locking ring 3, so as to improve the fit between the locking ring 3 and the frame 1. In this embodiment, the outer contour of the locking ring 3 is annular, and correspondingly, the longitudinal section of the mounting cavity 11 is circular, the jacks 13 are fan-shaped holes, and the three fan-shaped holes are located on the same circumference. The outer contour of the frame 1 can be set to be rectangular, polygonal, circular, or a bracket can be added on the basis of the circular shape.

[0026] In the lens heat shrink fixing device of this embodiment, please refer to Figures 4 to 11 The first side edge of the locking ring 3 is provided with the buckle 4 extending first away from the main body and then away from the axial direction, and the number of the buckles 4 is not more than the number of the slots 12.

[0027] It should be noted that the shape of the buckle 4 can be set to be circular, spherical or rectangular, etc., and a transition portion is provided between the buckle 4 and the locking ring body to improve the stability of the buckle 4 during the stretching process. The transition portion has a gradual cross-section, which can be a hyperbolic cross-section, an inverse functional curve cross-section or a trapezoidal curve cross-section, etc.

[0028] In the lens heat shrink fixing device of this embodiment, please refer to Figures 4 to 11 The second side edge of the locking ring 3 extends toward the axis direction thereof to form a limiting ring 7, the lens 5 is located between the limiting ring 7 and the clamping protrusion 2, and the inner diameter of the limiting ring 7 is smaller than the diameter of the lens 5; A first contact surface 8 is formed between the mirror surface on one side of the lens 5 and the limiting ring 7 , a second contact surface 9 is formed between the mirror surface on the other side of the lens 5 and the clamping protrusion 2 , and a third contact surface 10 is formed between the buckle 4 and the clamping groove 12 after heat shrinkage and heating.

[0029] Specifically, the first contact surface 8 is located between two side surfaces of the frame 1 , and the third contact surface 10 is located between two side surfaces of the lens 5 .

[0030] It should be noted that the first contact surface 8 is located on the right side of the second side surface of the frame 1, and the third contact surface 10 is located on the left side of the right side mirror surface of the lens 5, which effectively utilizes the high rigidity characteristics of the frame 1 and the lens 5 to effectively support the locking ring 3 and prevent the edge of the locking ring 3 from flipping over in a vibration environment, thereby causing the lens 5 to fall off.

[0031] In the lens heat shrink fixing device of this embodiment, please refer to Figures 4 to 12 The mounting cavity 11 of the frame 1 and the cylindrical surface of the lens 5 no longer use a matching tolerance, but a larger gap is left. Specifically, a plurality of threaded holes 14 are evenly distributed on the frame 1, and locking screws are arranged inside the threaded holes 14, the ends of which are against the cylindrical surface of the lens 5, and the relative position of the lens 5 is adjusted by tightening the screws.

[0032] According to an embodiment of the present invention, a method for heat shrinking and fixing a lens is provided. Figures 4 to 13 , including the following steps: S100, expanding the locking ring 3 in the radial direction and stretching the buckle 4 in the axial direction, and sleeve the expanded locking ring 3 on the periphery of the lens 5 until a first contact surface 8 is formed between a mirror surface of one side of the lens 5 and the locking ring 3; S200, inserting the stretched buckle 4 into the card slot 12, and assembling the lens 5 into the mounting cavity 11, until a second contact surface 9 is formed between the other side of the lens 5 and the frame 1; S300, heat and shrink the frame 1, the lens 5 and the locking ring 3 until the buckle 4 is engaged with the slot 12 to form a third contact surface 10, and the lens 5 is fixed by heat shrinkage.

[0033] It should be noted that the state of the buckle 4 before being stretched is as follows: Fig. 9 As shown by the solid line, the state of the buckle 4 after stretching is as follows Fig. 9As shown by the middle dotted line, specifically, before the buckle 4 is stretched, the axial distance between the first contact surface 8 and the third contact surface 10 is smaller than the axial distance between the two after the stretching is completed; before the locking ring 3 is expanded, its inner diameter should be smaller than the cylindrical diameter of the lens 5; the axial spacing between the first contact surface 8 and the buckle 4 after stretching is greater than the thickness of the lens 5, that is, after the buckle 4 is stretched, it is necessary to ensure that the axial spacing between the first contact surface 8 and the third contact surface 10 is greater than the thickness of the lens 5; after the buckle 4 is stretched, the outer contour size of the locking ring 3 is smaller than the size of the figure surrounded by the socket 13; during the assembly process, the axial position of the lens 5 is guaranteed by the fitting tolerance between the mounting cavity 11 and the cylindrical surface of the lens 5, that is, the relative position relationship between the axis of the lens 5 and the frame 1 after assembly is guaranteed by the machining accuracy, and no further adjustment is required; the locking ring 3 after heat shrinkage is tightly fitted to the lens 5, effectively ensuring the axial and radial support stiffness of the lens 5, and the axial support force is guaranteed by the cross-sectional area of ​​the buckle 4, and no supervision of the assembly process is required.

[0034] In the lens heat shrink fixing method of this embodiment, please refer to Figures 4 to 13 In step S300, the heat shrinking heating temperature is higher than the normal use temperature of the lens 5, and the heat shrinking heating temperature is lower than the normal use temperature of the lens coating layer.

[0035] It should be noted that when selecting the heat shrinking temperature, on the one hand, it should be higher than the normal use temperature of the lens 5 to avoid deformation of the lens 5 during use, and on the other hand, it should avoid the normal use temperature of the lens coating layer to avoid affecting the performance of the lens itself.

[0036] Preferably, the locking ring 3 is made of polytetrafluoroethylene, the heat shrinkage heating temperature is 100° C. to 250° C., and the heat preservation time is 8 min to 25 min.

[0037] Specifically, first use the tooling to expand the inner hole of the locking ring 3, and at the same time, evenly stretch the buckle 4 along the axial direction. Use a hollow bracket to hold the lens 5, and gradually put the inner hole of the locking ring 3 on the lens 5 along the axial direction until the first contact surface 8 is in contact. Place the frame 1 on the hollow bracket, and then clamp the outer contour of the locking ring 3, first pass the stretched buckle 4 through the card slot 12, adjust the relative position of the stretched buckle 4 and the card slot 12, so that the stretched buckle 4 is on the axis of the card slot 12, and then slowly move the lens 5 down, first ensuring that the cylindrical surface of the lens 5 slides into the installation cavity 11, and continue to move the lens 5 down until the second contact surface 9 forms an effective contact. Place the entire assembly structure with the bracket in a high-temperature box, gradually increase the temperature to 100℃~250℃, and keep it warm for 8min~25min, so that the locking ring 3 can fully deform and fix the lens 5, that is, complete the heat shrink fixation of the lens 5.

[0038] The present invention has been described in detail above. The above description is only a preferred embodiment of the present invention and should not limit the scope of implementation of the present invention. That is, all equivalent changes and modifications made within the scope of this application should still fall within the scope of the present invention.

Claims

1. A lens heat shrink fixing device, characterized in that: include: The frame has a mounting cavity for mounting the lens and a slot at the edge thereof; The locking ring is made of heat shrinkable material and is sleeved on the periphery of the lens. A buckle embedded in the slot is provided on the edge of the locking ring. After heat shrinkage and heating, the buckle is engaged with the slot.

2. A lens heat shrink fixing device according to claim 1, characterized in that: The first side edge of the frame is provided with a plurality of latching protrusions extending toward the axis direction thereof, adjacent latching protrusions are arranged at intervals to form the latching slot, and the interior of the latching protrusions is provided with a plug hole.

3. A lens heat shrink fixing device according to claim 2, characterized in that: The outer contour size of the locking ring is smaller than the size of the pattern surrounded by the jack.

4. A lens heat shrink fixing device according to claim 2, characterized in that: The first side edge of the locking ring is provided with buckles that first extend away from the main body and then extend away from the axis, and the number of the buckles is no more than the number of the slots.

5. A lens heat shrink fixing device according to claim 4, characterized in that: The second side edge of the locking ring extends toward the axis direction thereof to form a limiting ring, the lens is located between the limiting ring and the clamping protrusion, and the inner diameter of the limiting ring is smaller than the diameter of the lens; A first contact surface is formed between the mirror surface on one side of the lens and the limiting ring, a second contact surface is formed between the mirror surface on the other side of the lens and the clamping protrusion, and a third contact surface is formed between the buckle and the clamping groove after heat shrinkage and heating.

6. A lens heat shrink fixing device according to claim 5, characterized in that: The first contact surface is located between two side surfaces of the frame, and the third contact surface is located between two side mirror surfaces of the lens.

7. A method for heat shrinking and fixing lenses using the heat shrinking and fixing device for lenses according to any one of claims 1 to 6, characterized in that: The following steps are involved: S100, expanding the locking ring in its radial direction, stretching the buckle in its axial direction, and sleeve-arranging the expanded locking ring around the periphery of the lens until a first contact surface is formed between a mirror surface on one side of the lens and the locking ring; S200, inserting the stretched buckle into the card slot, and assembling the lens into the mounting cavity until a second contact surface is formed between the other side of the lens and the frame; S300, heat and shrink the frame, the lens and the locking ring until the buckle and the slot are engaged to form a third contact surface, and the lens is fixed by heat shrinking.

8. A lens heat shrink fixing method according to claim 7, characterized in that: In step S100, the axial distance between the first contact surface and the stretched buckle is greater than the thickness of the lens.

9. A lens heat shrink fixing method according to claim 7, characterized in that: In step S300, the heat shrinking heating temperature is higher than the normal use temperature of the lens, and the heat shrinking heating temperature is lower than the normal use temperature of the lens coating layer.

10. A lens heat shrinkage fixing method according to claim 9, characterized in that: The locking ring is made of polytetrafluoroethylene, the heat shrinkage heating temperature is 100°C to 250°C, and the insulation time is 8min to 25min.

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