A hollow retroreflector substrate and numerical control processing method thereof

Abstract

The present invention discloses a hollow retroreflector base, comprising a base and a reflecting part arranged on the upper part of the base; the reflecting part is a regular hexagonal prism structure with a notch cut out at the upper part, the notch of the reflecting part is composed of three reflecting surfaces intersecting in sequence, including a first reflecting surface, a second reflecting surface and a third reflecting surface; the first reflecting surface, the second reflecting surface and the third reflecting surface are all at an angle of 45° to the axial direction of the regular hexagonal prism. The present invention adopts a hollow regular hexagonal prism structure, which reduces the weight, and the three reflecting surfaces are obtained by machining at an angle of 45° to the axial direction, which increases the light aperture of the retroreflector, facilitates the capture of the target under the same incident condition, increases the energy of the reflected light, and realizes that any external light can return along the original path from any angle within the range of the entrance pupil diameter, thereby improving the optical path return accuracy of the reflected light.

Description

Technical Field

[0001] The invention belongs to the technical field of retroreflectors, and in particular relates to a hollow retroreflector substrate and a numerical control processing method thereof. Background Art

[0002] Hollow retroreflectors are used in the field of precision measurement, including long-distance precision distance measurement, speed measurement, remote sensing measurement, etc. Retroreflectors can reflect incident parallel light back and adjust the reflection angle of the reflected light according to the size of the incident angle. Currently, many light reflection devices on the market are not accurate enough and cannot meet the requirements of high precision, resulting in large reflection errors, which makes it more troublesome to set the incident angle.

[0003] There is a kind of corner cube prism with three mutually perpendicular reflecting surfaces inside the prism. The ranging light beam is reflected back to the measuring instrument by the three mutually perpendicular surfaces in the medium of air. There is no reflection and refraction process of glass in the middle, and the ranging laser energy is not attenuated by the prism. At the same time, since the constant of the corner cube prism has nothing to do with the size of the prism, there is no inherent constant error caused by the inconsistent refractive index of glass and air.

[0004] The working principle of the hollow retroreflector is to ensure that any light incident from any angle within the scope of the entrance pupil diameter can return along the same path, and its key indicator is angular accuracy. The higher the angular accuracy, the better the accuracy and performance of the return along the same path.

[0005] Under the same incident conditions, the larger the entrance pupil diameter, that is, the larger the aperture, the easier it is to capture the target and increase the energy of the reflected light. The larger the range of incident light that the hollow retroreflector can accept, the wider the application range. However, how to increase the entrance pupil volume while ensuring accuracy to improve reflection accuracy is something that technicians need to further study.

[0006] Patent CN109856716A discloses a method for processing, shaping and modulating a hollow retroreflector, firstly, the square substrate for assembling the hollow retroreflector is glued on the solid corner pyramid, then the whole is cut into a circle by an engraving machine or a laser cutting machine, then the inner side of the cut elliptical arc substrate is plated with a metal protective film, and then the elliptical arc substrate is glued on the angle precision adjustment platform to adjust the angle precision, and the interference fringes are observed by a laser interferometer, and the angle precision of the three substrates is adjusted by the change of the fringes, and the square substrate is glued on the solid corner pyramid, and then the whole is tilted and cut into a circle by a cutting machine. However, the aperture of the hollow retroreflector disclosed in the patent is limited and still needs to be further improved.

[0007] As for the retroreflector base parts, CNC machining technology is currently used, but there are problems such as high requirements for bevel accuracy, small size and difficulty in machining, and chamfering and rounding require manual programming, which increases labor costs and production time costs. Summary of the invention

[0008] The purpose of the present invention is to provide a hollow retroreflector substrate and a numerical control processing method thereof in order to solve the above problems.

[0009] The purpose of the present invention is achieved through the following technical solutions:

[0010] A hollow retroreflector substrate comprises a base and a reflecting portion arranged on the upper portion of the base;

[0011] The reflecting part is a regular hexagonal prism structure with a notch cut out at the top, and the notch of the reflecting part is composed of three reflecting surfaces intersecting in sequence, including a first reflecting surface, a second reflecting surface and a third reflecting surface;

[0012] The first reflecting surface, the second reflecting surface and the third reflecting surface all form an angle of 45° with the axial direction of the regular hexagonal prism, and are planes processed from vertices of the first, third and fifth side edges of the regular hexagonal prism at the same height.

[0013] Compared with the existing hollow retroreflectors, the reflective portion of the present invention adopts a regular hexagonal prism structure with a notch dug out at the top, and the notch of the reflective portion is composed of three reflective surfaces that intersect in sequence. Compared with the existing corner cube prisms with three mutually perpendicular reflective surfaces, due to the structure of the regular hexagonal prism, the three reflective surfaces are obtained by machining at an angle of 45° to the axial direction, and most of the side edges of the regular hexagonal prism are removed, thereby increasing the light aperture of the retroreflector, ensuring that under the same incident conditions, it is easy to capture the target and increase the energy of the reflected light. At the same time, the three reflective surfaces intersect, so that any external light that is incident from any angle within the range of the entrance pupil diameter can return along the same path, thereby improving the accuracy of the optical path return of the reflected light.

[0014] Furthermore, the first reflecting surface, the second reflecting surface and the third reflecting surface have the same shape, which are all quadrilaterals.

[0015] Furthermore, the first reflecting surface, the second reflecting surface and the third reflecting surface are all equilateral quadrilaterals, and the first reflecting surface, the second reflecting surface and the third reflecting surface intersect with each other to form a three-dimensional reflecting surface system.

[0016] Furthermore, the side length of the regular hexagonal prism is 28.1 mm, and the side lengths of the first reflecting surface, the second reflecting surface and the third reflecting surface are 48.7 mm.

[0017] Furthermore, the base is cylindrical.

[0018] Furthermore, the diameter of the cylinder is 38.1 mm.

[0019] Furthermore, a threaded mounting hole is provided at the center of the base.

[0020] Furthermore, the reflective portion and the base are integrally formed, which provides better stability and precision.

[0021] Furthermore, the surfaces of the first reflecting surface, the second reflecting surface and the third reflecting surface are coated with a reflecting film, the material of the reflecting film is metal or dielectric coating, and the thickness of the reflecting film is 30nm to 100nm.

[0022] A method for numerical control machining of a hollow retroreflector substrate, using a five-axis numerical control machine tool, comprises the following steps:

[0023] Step 1. Clamp one end of the blank, clamp the outer circle of one end with a three-jaw chuck, drill the center hole first, then change the turning tool and turn the round base;

[0024] Step 2. Turn around and clamp the other end of the part. Use a three-jaw chuck to clamp the machined circular base. First, machine a regular hexagonal prism. Then, use a milling cutter to mill square planes from the first, third, and fifth vertices of the regular hexagonal prism. The angle of the square plane is 45° to the axis of the regular hexagonal prism.

[0025] Step 3: Carve the plane.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] 1. The hollow hexagonal prism structure is adopted, and the three reflective surfaces are machined at an angle of 45° to the axis. Due to the unique structure of the hexagonal prism, this structure can eliminate more parts, increase the proportion of the reflective surface, and thus increase the aperture of the retroreflector. Under the same incident conditions, it can easily capture the target, increase the energy of the reflected light, and realize that any external light incident from any angle within the scope of the entrance pupil diameter can return along the original path, thereby improving the accuracy of the optical path return of the reflected light and reducing the weight.

[0028] 2. Since the mirror parts of the retroreflector base have complex requirements and cannot be processed on a plane milling machine, the present invention uses a five-axis machine tool, which can reduce the manual clamping and tool changing steps when processing complex surfaces, thereby improving the accuracy of the process dimensions of the retroreflector, meeting the requirements of form and position tolerance and dimensional tolerance accuracy, solving the complex processing procedures encountered by the retroreflector parts in the processing and production, and at the same time improving the dimensional accuracy of the retroreflector parts. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 A three-dimensional diagram of the hollow retroreflector substrate of the present invention;

[0030] Figure 2 Schematic diagram of each reflective surface of the reflective part of the hollow retroreflector base of the present invention;

[0031] Figure 3 A three-dimensional diagram of the bottom view of the hollow retroreflector substrate of the present invention;

[0032] Figure 4 It is a top view of the hollow retroreflector substrate of the present invention;

[0033] In the figure: 1-base; 2-reflecting part; 101-threaded mounting hole; 201-first reflecting surface; 202-second reflecting surface; 203-third reflecting surface. DETAILED DESCRIPTION

[0034] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0035] like Figure 1 , 4 A hollow retroreflector substrate comprises a base 1 and a reflecting portion 2 arranged on the upper portion of the base 1; the reflecting portion 2 is a regular hexagonal prism structure with a notch cut out at the upper portion, the notch of the reflecting portion 2 is composed of three reflecting surfaces intersecting in sequence, including a first reflecting surface 201, a second reflecting surface 202 and a third reflecting surface 203; the first reflecting surface 201, the second reflecting surface 202 and the third reflecting surface 203 are all at an angle of 45° to the axial direction of the regular hexagonal prism.

[0036] like Figure 2 , the first reflecting surface 201, the second reflecting surface 202 and the third reflecting surface 203 have the same shape, which are all equilateral quadrilaterals. The side length of the regular hexagonal prism is 28.1 mm, the side length of the first reflecting surface 201, the second reflecting surface 202 and the third reflecting surface 203 is 48.7 mm, the surfaces of the first reflecting surface 201, the second reflecting surface 202 and the third reflecting surface 203 are coated with a reflecting film, the material of the reflecting film is a metal or dielectric coating, the thickness of the reflecting film is 30 nm to 100 nm, the base 1 is cylindrical, and the diameter is 38.1 mm, as shown in FIG. Figure 3 The center of the base 1 is provided with a threaded mounting hole 101. The reflector 2 is integrally formed with the base 1 and is manufactured by a CNC machine tool.

[0037] Compared with the existing hollow retroreflectors, the reflective portion 2 of the present invention adopts a regular hexagonal prism structure with a notch cut out at the top, and the notch of the reflective portion 2 is composed of three reflective surfaces intersecting in sequence. Compared with the existing corner cube prism with three mutually perpendicular reflective surfaces, due to the structure of the regular hexagonal prism, the three reflective surfaces are obtained by machining at an angle of 45° to the axial direction, and most of the side edges of the regular hexagonal prism are removed, thereby increasing the light aperture of the retroreflector, ensuring that under the same incident conditions, it is easy to capture the target and increase the energy of the reflected light. At the same time, the three reflective surfaces intersect, so that any external light incident from any angle within the range of the entrance pupil diameter can return along the same path, thereby improving the accuracy of the optical path return of the reflected light.

[0038] A CNC machining method for a hollow retroreflector base body, using a five-axis CNC machine tool for machining. The machining method includes: designing tool parameters (number of teeth, diameter, helix angle, rake angle, back angle, RC), machining parameters (cutting depth, feed, speed), and part information (material); building a three-dimensional model of the part; designing the turning tool path; changing the tool, designing the milling tool path; machining threaded holes; selecting appropriate tool path data for clamping and turning; designing the turning tool path data; changing the tool, and drilling threaded holes. Simulation machining aims to improve the accuracy of nozzle parts and optimize the tool path.

[0039] The processing includes the following steps:

[0040] Step 1: Clamp one end of the blank with a three-jaw chuck For outer circle, first drill the hole center. Then change the turning tool and turn the outer diameter And a 13.75mm long contour, then the plane is turned to light and the coordinate is set to Z0.0, and the outer chamfer is 1×45°;

[0041] Step 2: Turn around and clamp the other end of the workpiece. Use the three-jaw chuck to clamp the machined Outer circle:

[0042] 1. First, carve a regular hexagon with a side length of 28.1 mm.

[0043] 2. Use a milling cutter to mill a square plane with a length of 48.7 mm from one vertex of the regular hexagon at an angle of 45°

[0044] 3. Use the milling cutter to mill a square plane with a length of 48.7mm and an angle of 45° from the third vertex.

[0045] 4. Use a milling cutter to mill a square plane with a length of 48.7 mm and an angle of 45° from the fifth vertex.

[0046] Step 3, plane turning: Roughly turn the plane until the product length is 51.48mm.

[0047] The above description of the embodiments is to facilitate the understanding and use of the invention by those skilled in the art. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative work. Therefore, the present invention is not limited to the above embodiments, and improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the present invention should be within the scope of protection of the present invention.

Claims

1. A hollow retroreflector substrate, characterized in that: It comprises a base and a reflecting part arranged on the upper part of the base; The reflecting part is a regular hexagonal prism structure with a notch cut out at the top, and the notch of the reflecting part is composed of three reflecting surfaces intersecting in sequence, including a first reflecting surface, a second reflecting surface and a third reflecting surface; The first reflecting surface, the second reflecting surface and the third reflecting surface are all at an angle of 45° to the axial direction of the regular hexagonal prism; The hollow retroreflector substrate is processed by a five-axis CNC machine tool, including the following steps: Step 1. Clamp one end of the blank, clamp the outer circle of one end with a three-jaw chuck, drill the center hole first, then change the turning tool and turn the round base; Step 2. Turn around and clamp the other end of the part. Use a three-jaw chuck to clamp the machined circular base. First, machine a regular hexagonal prism. Then, use a milling cutter to mill square planes from the first, third, and fifth vertices of the regular hexagonal prism. The angle of the square plane is 45° to the axis of the regular hexagonal prism. Step 3: Carve the plane.

2. A hollow retroreflector substrate according to claim 1, characterized in that: The first reflecting surface, the second reflecting surface and the third reflecting surface have the same shape, which are all quadrilaterals.

3. A hollow retroreflector substrate according to claim 2, characterized in that: The first reflecting surface, the second reflecting surface and the third reflecting surface are all equilateral quadrilaterals.

4. A hollow retroreflector substrate according to claim 3, characterized in that: The side length of the regular hexagonal prism is 28.1 mm, and the side lengths of the first reflecting surface, the second reflecting surface and the third reflecting surface are 48.7 mm.

5. The hollow retroreflector substrate according to claim 4, characterized in that: The base is cylindrical.

6. The hollow retroreflector substrate according to claim 5, characterized in that: The diameter of the cylinder is 38.1 mm.

7. The hollow retroreflector substrate according to claim 6, characterized in that: A threaded mounting hole is provided at the center of the base.

8. The hollow retroreflector substrate according to claim 1, characterized in that: The reflecting portion and the base are integrally formed.

9. The hollow retroreflector substrate according to claim 1, characterized in that: The surfaces of the first reflecting surface, the second reflecting surface and the third reflecting surface are plated with reflecting films, the material of the reflecting films is metal or dielectric coating, and the thickness of the reflecting films is 30nm-100nm.

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