Component surface high-precision three-dimensional contour measuring platform based on laser interference feedback

Abstract

The utility model relates to the field of component three-dimensional contour detection, in particular to a component surface high-precision three-dimensional contour measuring platform based on laser interference feedback. A component surface high-precision three-dimensional profile measuring platform based on laser interference feedback comprises a movement mechanism, a supporting block and a measuring head mechanism fixed to the upper portion of the supporting block through a supporting frame, and the movement mechanism is used for achieving X-direction movement, Y-direction movement and Z-direction movement of the supporting block; the supporting block is provided with a Z-direction positioning part, the side of the Z-direction positioning part is connected with an X-direction positioning part and a Y-direction positioning part, and the surfaces of the Z-direction positioning part, the X-direction positioning part and the Y-direction positioning part are provided with a Z-direction reference positioning surface, an X-direction reference positioning surface and a Y-direction reference positioning surface which are subjected to mirror surface treatment respectively; and an X-direction laser interferometer, a Y-direction laser interferometer and a Z-direction laser interferometer are fixed on the support frame. The device has the advantage that the measurement precision of the three-dimensional profile of the surface of the component can be improved.

Description

Technical Field

[0001] The utility model relates to the field of component three-dimensional profile detection, and in particular to a component surface high-precision three-dimensional profile measurement platform based on laser interference feedback. Background Art

[0002] Precision measurement of component surface profile is an important way to ensure component processing quality and normal use. Traditionally, component surface profile measurement is mainly performed using white light interferometers and three-dimensional coordinate measuring machines.

[0003] A white light interferometer is a measuring instrument based on the interference phenomenon. It uses the interference phenomenon of white light to measure the optical path difference and thus obtain information such as the morphology of the measured object. However, the measurement accuracy is usually less than 500μm and the measurement range is limited. It is difficult to measure components with large surface morphology fluctuations. For components with larger areas, measurement can only be carried out by splicing, which reduces measurement accuracy and efficiency.

[0004] A three-dimensional coordinate measuring machine is a measuring instrument that obtains surface profile information by measuring the spatial coordinates of points on the surface of a component. Its measurement accuracy is affected by factors such as the measurement accuracy of the grating scale, the sensing accuracy of the probe system, the Abbe error, and the thermal deformation of the mechanical structure. Chinese patent application number 202021302292.1 discloses a high-precision three-dimensional profile scanning measurement platform based on glass guide rails. This solution can only improve the movement accuracy of the motion mechanism by making the motion mechanism of the mechanical system adopt components made of microcrystalline glass with a low thermal expansion coefficient. However, this solution relies on the Y- and Z-axis motion mechanisms to realize the movement of the probe mechanism, and the X-axis motion mechanism to realize the movement of the component to be measured. The distance between the axes is large, and the resulting geometric error is large. In addition, the probe mechanism is also driven to move, and its detection performance will also be affected, resulting in low overall detection accuracy. Utility Model Content

[0005] The utility model aims to provide a high-precision three-dimensional profile measurement platform for component surfaces based on laser interference feedback, which is convenient for realizing high-precision measurement.

[0006] To achieve the above objectives, the utility model adopts a high-precision three-dimensional contour measurement platform for component surfaces based on laser interference feedback, comprising a motion mechanism, a support block for supporting the component to be measured, and a probe mechanism fixed above the support block via a support frame, wherein the probe mechanism includes a vertically arranged stylus, the support block is fixed to the output end of the motion mechanism, and the motion mechanism is used to realize the movement of the support block in the X, Y and Z directions;

[0007] The support block has a horizontal Z-direction positioning portion, and the Z-direction positioning portion is laterally connected to an upwardly extending X-direction positioning portion and a Y-direction positioning portion. The Z-direction positioning portion, the X-direction positioning portion, and the Y-direction positioning portion form a semi-enclosed cavity for placing the component to be measured. The surfaces of the Z-direction positioning portion, the X-direction positioning portion, and the Y-direction positioning portion away from the semi-enclosed cavity respectively have a mirror-finished Z-direction reference positioning surface, an X-direction reference positioning surface, and a Y-direction reference positioning surface;

[0008] An X-axis laser interferometer facing the X-axis reference positioning surface, a Y-axis laser interferometer facing the Y-axis reference positioning surface, and a Z-axis laser interferometer facing the Z-axis reference positioning surface are fixed on the support frame. The optical path extension lines of the X-axis laser interferometer, the Y-axis laser interferometer and the Z-axis laser interferometer intersect orthogonally at the lower end of the measuring needle.

[0009] The motion mechanism of the present invention is not used to drive the probe mechanism to move. The probe mechanism is fixed and does not move, thus avoiding problems such as vibration, shaking and position deviation caused by the movement of the probe mechanism itself, so that the probe can contact the surface of the component to be measured more stably and accurately, thereby improving measurement accuracy. In traditional solutions, the distance between the axes is large, which is prone to geometric errors. However, the present invention directly drives the support block and the component to move through the motion mechanism, reducing the accumulation of geometric errors caused by the large axis spacing, making the measurement results more accurate. There is no need to control the movement of the probe at the same time, which simplifies the complexity of the motion control system. According to the shape of the component to be measured and the measurement requirements, the motion mechanism can flexibly adjust the position of the support block, so that the probe can quickly and accurately reach each measurement point, reducing unnecessary movement and waiting time, and further improving measurement efficiency. The motion mechanism of the present invention can adopt any one of the existing mechanisms for achieving X-, Y- and Z-direction movement in existing three-dimensional contour detection.

[0010] This utility model utilizes three laser interferometers mounted on a support frame. Each optical path is reflected back to the laser interferometer detection system via three mirror-treated reference positioning surfaces, facilitating measurement of the three-dimensional coordinates of the support block and enabling closed-loop motion control. Furthermore, the extended optical paths intersect orthogonally at the stylus of the probe, eliminating the effects of Abbe errors. The laser interferometer of this utility model can utilize existing high-precision measurement laser interferometers, including a laser, a detection system, and a signal processing circuit. The laser provides a light source with stable frequency and intensity, while the detection system receives light reflected from the support block. Finally, the signal processing circuit calculates the position of the measured target.

[0011] Preferably, the optical path of the Z-axis laser interferometer is arranged vertically, the motion mechanism forms a make way hole for the optical path of the Z-axis laser interferometer, and the optical paths of the X-axis laser interferometer, the Y-axis laser interferometer and the Z-axis laser interferometer are arranged orthogonally in pairs.

[0012] The orthogonal optical path setting ensures consistent optical path conditions for each measurement, reducing measurement errors caused by optical path variations and improving the repeatability and consistency of measurement results. This optical path setting also facilitates a compact layout of the measurement platform, making the overall structure more rational, saving space, and facilitating integration into various production or laboratory environments. Because the motion mechanism must drive the support block, while the support frame and Z-axis laser interferometer are stationary, the aperture of the clearance hole should be as large as possible.

[0013] Preferably, a grating scale mechanism is provided on the motion mechanism side for feeding back the moving distance of the support block.

[0014] The motion mechanism of the utility model is used for the X, Y and Z displacement of the support platform and the component, and utilizes the grating scale mechanism and the support platform closed-loop feedback motion control system to drive the component to perform three-dimensional displacement. Three orthogonally arranged laser interferometers are used to more accurately measure the component displacement, effectively separating the motion measurement, and can greatly reduce the mutual influence caused by the motion and measurement of the support platform and the component, thereby improving the accuracy of the three-dimensional profile measurement of the component surface.

[0015] Preferably, the support frame includes a frame top located above the support block, a frame bottom located below the support block and a frame side located on the side of the support block, the X-axis laser interferometer and the Y-axis laser interferometer are fixed to the frame side or the frame top, and the Z-axis laser interferometer is fixed to the frame bottom. The frame top and the frame bottom are both square plate-shaped, and a first clearance groove running through the top and the bottom of the square plate-shaped frame is provided at the center of the frame top and the center of the frame bottom. The frame side includes three vertical plates, and the three corners of the frame top and the three corners of the frame bottom are respectively connected to one vertical plate, and a second clearance groove is formed between adjacent vertical plates.

[0016] The design of the first and second clearance slots reduces the weight of the support frame, achieving lightweight construction. This weight reduction not only lowers production costs but also reduces gravitational deformation of the support frame itself. Gravitational deformation, the deformation of a large structure under its own weight, can affect the accuracy of the measurement platform. The design of the first and second clearance slots effectively minimizes this gravitational deformation, thereby improving the measurement accuracy and stability of the measurement platform and ensuring the reliability of measurement results.

[0017] Preferably, a fixing protrusion is provided at the connection between the top of the frame and the side of the frame, the thickness of the fixing protrusion is smaller than the thickness of the top of the frame and the thickness of the side of the frame, and the X-axis laser interferometer and the Y-axis laser interferometer are respectively fixed at a fixing protrusion.

[0018] The thickness of the fixing protrusions is smaller than that of the frame's top and sides, meeting the requirements for laser interferometer installation without significantly weakening the frame's overall structural rigidity. Compared to methods that directly slot or drill holes in the frame's top and sides for laser interferometer installation, this method better maintains the support frame's strength and stability, enabling it to withstand certain external loads and vibrations while preventing deformation or damage due to insufficient structural strength.

[0019] Preferably, the support block and the support frame are both made of a one-piece structure using a material with a low thermal expansion coefficient. Since the outer surface of the support block needs to be mirror-finished, the support block can be made of glass-ceramic and the support frame can be made of marble.

[0020] The utility model has the advantages of being convenient for closed-loop feedback, being able to measure component displacement more accurately, being convenient for separating movement and measurement, and being able to greatly reduce the mutual influence brought about by platform movement and measurement, thereby improving the accuracy of three-dimensional profile measurement of component surface. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a structural schematic diagram of the present utility model.

[0022] Figure 2 This is a structural diagram of the support frame of the present utility model. DETAILED DESCRIPTION

[0023] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0024] Depend on Figure 1 and Figure 2 As shown, this embodiment discloses a high-precision three-dimensional surface contour measurement platform for a component based on laser interferometric feedback. The platform comprises a motion mechanism 100, a support block 1 for supporting the component to be measured, and a probe mechanism 200 fixed to the support block 1 via a support frame 2. The probe mechanism 200 includes a vertically arranged stylus 29. Both the support block 1 and the support frame 2 are integral structures made of a material with a low thermal expansion coefficient: the support block 1 is made of microcrystalline glass, and the support frame 2 is made of marble.

[0025] Depend on Figure 1 As shown, the support block 1 has a flat Z-axis positioning portion 11, and the Z-axis positioning portion 11 is laterally connected to an upwardly extending X-axis positioning portion 12 and a Y-axis positioning portion 13. A semi-enclosed cavity for placing the component to be measured is formed between the Z-axis positioning portion 11, the X-axis positioning portion 12 and the Y-axis positioning portion 13, and the surfaces of the Z-axis positioning portion 11, the X-axis positioning portion 12 and the Y-axis positioning portion 13 away from the semi-enclosed cavity have a mirror-treated Z-axis reference positioning surface, an X-axis reference positioning surface and a Y-axis reference positioning surface, respectively.

[0026] Depend on Figure 1 and Figure 2 As shown, an X-axis laser interferometer 31 facing the X-axis reference positioning surface, a Y-axis laser interferometer 32 facing the Y-axis reference positioning surface, and a Z-axis laser interferometer 33 facing the Z-axis reference positioning surface are fixed to the support frame 2. The optical path extensions of the X-axis laser interferometer 31, the Y-axis laser interferometer 32, and the Z-axis laser interferometer 33 intersect orthogonally at the lower end of the stylus 29. The optical path of the Z-axis laser interferometer 33 is arranged vertically, while the optical paths of the X-axis laser interferometer 31 and the Y-axis laser interferometer 32 are arranged horizontally. The optical paths of the X-axis laser interferometer 31, the Y-axis laser interferometer 32, and the Z-axis laser interferometer 33 are arranged orthogonally to each other.

[0027] Support block 1 is fixed to the output end of motion mechanism 100, which is used to achieve movement of the support block in the X, Y, and Z directions. Motion mechanism 100 includes a Z-axis motion stage and an XY coplanar motion stage. The Z-axis motion stage is fixed to the output end of the XY coplanar motion stage, and support block 1 is fixed to the output end of the Z-axis motion stage. Motion mechanism 100 forms a clearance hole for the optical path of Z-axis laser interferometer 33. A grating scale mechanism 101 is installed on the side of motion mechanism 100 to provide feedback on the movement distance of support block 1.

[0028] The support frame 2 includes a frame top 21 located above the support block 1, a frame bottom 22 located below the support block 1, and a frame side 23 located to the side of the support block 1. The X-axis laser interferometer 31 and the Y-axis laser interferometer 32 are fixed to the frame side 23, and the Z-axis laser interferometer is fixed to the frame bottom 22. The frame top 21 and the frame bottom 22 are both square plate-shaped, and a square first clearance groove 20 is provided at the center of each of the square plate-shaped frame top 21 and the center of each frame bottom 22. The frame side 23 includes three vertical plates, with a vertical plate connecting each of the three corners of the frame top 21 and the three corners of the frame bottom 22. Second clearance grooves 24 are formed between adjacent vertical plates.

[0029] Among them, a fixing protrusion 25 is provided at the connection between the frame top 21 and the frame side 23. The thickness of the fixing protrusion 25 is smaller than the thickness of the frame top 21 and the thickness of the frame side 23. The X-axis laser interferometer 31 and the Y-axis laser interferometer 32 are respectively fixed at a fixing protrusion 25.

[0030] This embodiment has the advantages of facilitating closed-loop feedback, enabling more accurate measurement of component displacement, facilitating separation of motion and measurement, and significantly reducing the mutual influence between platform motion and measurement, thereby improving the accuracy of component surface three-dimensional profile measurement.

Claims

1. A high-precision three-dimensional surface contour measurement platform for a component based on laser interferometric feedback, comprising a motion mechanism, a support block for supporting the component to be measured, and a probe mechanism fixed above the support block via a support frame, the probe mechanism including a vertically arranged stylus, characterized in that: The support block is fixed to the output end of the motion mechanism, and the motion mechanism is used to realize the movement of the support block in the X, Y and Z directions; The support block has a horizontal Z-direction positioning portion, and the Z-direction positioning portion is laterally connected to an upwardly extending X-direction positioning portion and a Y-direction positioning portion. The Z-direction positioning portion, the X-direction positioning portion, and the Y-direction positioning portion form a semi-enclosed cavity for placing the component to be measured. The surfaces of the Z-direction positioning portion, the X-direction positioning portion, and the Y-direction positioning portion away from the semi-enclosed cavity respectively have a mirror-finished Z-direction reference positioning surface, an X-direction reference positioning surface, and a Y-direction reference positioning surface; An X-axis laser interferometer facing the X-axis reference positioning surface, a Y-axis laser interferometer facing the Y-axis reference positioning surface, and a Z-axis laser interferometer facing the Z-axis reference positioning surface are fixed on the support frame. The optical path extension lines of the X-axis laser interferometer, the Y-axis laser interferometer and the Z-axis laser interferometer intersect orthogonally at the lower end of the measuring needle.

2. The high-precision three-dimensional contour measurement platform for component surfaces based on laser interference feedback according to claim 1, characterized in that: The optical path of the Z-axis laser interferometer is arranged vertically, the motion mechanism forms a clearance hole for the optical path of the Z-axis laser interferometer, and the optical paths of the X-axis laser interferometer, the Y-axis laser interferometer and the Z-axis laser interferometer are arranged orthogonally in pairs.

3. The high-precision three-dimensional contour measurement platform for component surfaces based on laser interference feedback according to claim 2, characterized in that: The motion mechanism side is provided with a grating scale mechanism for feeding back the moving distance of the support block.

4. The high-precision three-dimensional contour measurement platform for component surfaces based on laser interference feedback according to claim 1, characterized in that: The support frame includes a frame top located above the support block, a frame bottom located below the support block and a frame side located on the side of the support block. The X-axis laser interferometer and the Y-axis laser interferometer are fixed to the frame side or the frame top, and the Z-axis laser interferometer is fixed to the frame bottom. The frame top and the frame bottom are both square plate-shaped, and the center of the square plate-shaped frame top and the center of the frame bottom are both provided with a first clearance groove running through the upper and lower parts. The frame side includes three vertical plates, and the three corners of the frame top and the three corners of the frame bottom are respectively connected to one vertical plate, and a second clearance groove is formed between adjacent vertical plates.

5. The high-precision three-dimensional contour measurement platform for component surfaces based on laser interference feedback according to claim 4, characterized in that: A fixing protrusion is provided at the connection between the top of the frame and the side of the frame. The thickness of the fixing protrusion is smaller than the thickness of the top of the frame and the thickness of the side of the frame. The X-axis laser interferometer and the Y-axis laser interferometer are respectively fixed at a fixing protrusion.

6. The high-precision three-dimensional surface profile measurement platform based on laser interference feedback according to claim 1, characterized in that: The support block and the support frame are both integral structures made of materials with low thermal expansion coefficient.

Images