Online measurement method for microstructure feature part

Abstract

The invention relates to the technical field of on-line measurement, in particular to an on-line measurement method for a microstructure feature part, which comprises the following steps: mounting a microscope lens on a tool table of a machine tool, controlling the X-axis and Z-axis movement of the machine tool, observing and positioning the microscopic features of the part, and recording the initial values of the X-axis and Z-axis coordinates of the machine tool; disassembling the microscope lens, then installing a spectrum confocal measuring head, and determining adjustment values of the X-axis and Z-axis coordinates of the machine tool according to the initial values of the X-axis and Z-axis coordinates of the machine tool and a predetermined offset value; the adjustment values of the X-axis and Z-axis coordinates of the machine tool are input into a numerical control system of the machine tool, and the spectrum confocal measuring head is positioned at the microscopic characteristics of the part. According to the method, online measurement of the microstructure features after the ultraprecise single-point diamond lathe machines the microstructure feature parts can be realized, the practicability of the lathe is improved, and the measurement investment cost is saved.

Description

Technical Field

[0001] The present application relates to the field of on-line measurement technology, and particularly to an on-line measurement method for micro-structural feature parts. Background Art

[0002] Ultra-precision single-point diamond lathes can be used to machine micro-structural feature parts, such as micro-groove step features, diffraction step features, Fresnel step features, etc. The height of these steps is often on the micron scale. After machining, it is necessary to detect the height data of the step features to judge the machining quality. Traditionally, it is necessary to additionally configure off-line measurement equipment, and the parts are removed from the machine tool and measured on the off-line measurement equipment. Configuring a probe for the ultra-precision single-point diamond lathe can achieve on-line measurement of parts. Contact LVDT probes have been widely used on ultra-precision single-point diamond lathes for on-line measurement of the surface profile accuracy of parts. Non-contact measurement, due to the characteristic of not easily scratching the surface of the parts, has been used by domestic and foreign scholars and research institutions for on-line measurement of parts on ultra-precision single-point diamond lathes. In non-contact measurement, compared with line-scanning measurement and surface-scanning measurement, the point-scanning measurement method has higher measurement accuracy. However, since the step features of the parts are on the order of a few microns, it is not easy to observe the specific position on the machine tool, and it is still difficult to realize on-line measurement of the micro-structural features of micro-structural feature parts on an ultra-precision single-point diamond machine tool. Summary of the Invention

[0003] To solve the above problems, the present application provides an on-line measurement method for micro-structural feature parts, including:

[0004] Install a microscopic lens on the machine tool tooling table, control the movement of the X-axis and Z-axis of the machine tool, observe and position the microscopic features of the part, and record the initial values of the X-axis and Z-axis coordinates of the machine tool;

[0005] Remove the microscopic lens and then install a spectral confocal probe. According to the initial values of the X-axis and Z-axis coordinates of the machine tool and the pre-determined offset value, determine the adjustment values of the X-axis and Z-axis coordinates of the machine tool;

[0006] Input the adjustment values of the X-axis and Z-axis coordinates of the machine tool into the machine tool numerical control system to position the spectral confocal probe at the microscopic features of the part.

[0007] Further, before installing the microscopic lens on the machine tool tooling table, controlling the movement of the X-axis and Z-axis of the machine tool, observing and positioning the microscopic features of the part, and recording the initial values of the X-axis and Z-axis coordinates of the machine tool, it further includes:

[0008] Calibrate the microscopic lens and the spectral confocal probe respectively using a calibration piece to determine the offset value of the spectral confocal probe relative to the microscopic lens in the machine tool coordinate system.

[0009] Further, the step of respectively calibrating the microscopic lens and the spectral confocal probe using the calibration piece to determine the offset value of the spectral confocal probe relative to the microscopic lens in the machine tool coordinate system includes:

[0010] Install the microscopic lens on the machine tool fixture table, adjust the up and down movement of the microscopic lens, control the movement of the X-axis and Z-axis of the machine tool, calibrate the microscopic lens using the calibration piece, and record the X-axis coordinate X of the machine tool M and the Z-axis coordinate Z M ;

[0011] Remove the microscopic lens and then install the spectral confocal probe, adjust the up and down movement of the spectral confocal probe, control the movement of the X-axis and Z-axis of the machine tool, calibrate the spectral confocal probe using the calibration piece, and record the X-axis coordinate X of the machine tool P and the Z-axis coordinate Z P ;

[0012] Determine the offset value X of the spectral confocal probe relative to the microscopic lens in the machine tool coordinate system offset = X P - X M , Z offset = Z P - Z M .

[0013] Further, the step of respectively calibrating the microscopic lens and the spectral confocal probe using the calibration piece to determine the offset value of the spectral confocal probe relative to the microscopic lens in the machine tool coordinate system further includes:

[0014] Fix a calibration piece with a cross mark in the middle on the machine tool spindle, and adjust the alignment of the calibration piece with the machine tool spindle.

[0015] Further, the alignment accuracy of the calibration piece with the machine tool spindle is better than 1 micron.

[0016] Further, the step of calibrating the microscopic lens using the calibration piece includes:

[0017] Align the microscopic lens with the cross of the calibration piece, and the image center of the microscopic lens is the cross of the calibration piece.

[0018] Further, the step of calibrating the spectral confocal probe using the calibration piece includes:

[0019] Align the spectral confocal probe with the center of the cross of the calibration piece, and the measurement reading of the spectral confocal probe is in the middle of the range.

[0020] Further, the step of inputting the adjustment values of the X-axis and Z-axis coordinates of the machine tool in the machine tool numerical control system and positioning the spectral confocal probe at the microscopic features of the part further includes:

[0021] The microscopic features are measured through a planned measurement procedure, and the height data of the microscopic features is obtained by analyzing and calculating the measurement data.

[0022] The above technical solution of this application has the following advantages:

[0023] The on-line measurement method for microstructural feature parts provided by this application installs a microscopic lens on the machine tool tooling table, controls the movement of the X-axis and Z-axis of the machine tool, observes and locates the microscopic features of the parts, records the initial values of the coordinates of the X-axis and Z-axis of the machine tool, disassembles the microscopic lens and then installs a spectral confocal probe. According to the initial values of the coordinates of the X-axis and Z-axis of the machine tool and the pre-determined offset values, the adjustment values of the coordinates of the X-axis and Z-axis of the machine tool are determined. The adjustment values of the coordinates of the X-axis and Z-axis of the machine tool are input into the machine tool numerical control system, and the spectral confocal probe is positioned at the microscopic features of the parts, which can realize the on-line measurement of the microstructural features after machining microstructural feature parts by an ultra-precision single-point diamond lathe, improve the practicability of the machine tool, and save the measurement investment cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the specific embodiments of this application or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of this application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0025] Figure 1 Schematic diagram of the calibration part provided by this application;

[0026] Figure 2 Front view schematic diagram of the microscopic lens positioning measurement provided by this application before measurement;

[0027] Figure 3 Front view schematic diagram of the accurate measurement of the spectral confocal probe provided by this application;

[0028] Figure 4 Top view of the machine tool provided by this application;

[0029] Figure 5 Schematic diagram of the fixation of the microscopic lens and the spectral confocal probe on the machine tool housing provided by this application.

[0030] Reference numerals: 1 - calibration part; 2 - microstructural feature part; 3 - microscopic lens and tooling; 4 - spectral confocal probe and tooling; 5 - measurement fixing tooling; 6 - machine tool spindle; 7 - machine tool tooling table; 8 - machine tool housing; 9 - suspension location of the microscopic lens and tooling; 10 - suspension location of the spectral confocal probe and tooling. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0031] In the following description, specific details such as specific system architectures, technologies, etc. are presented for the purpose of illustration rather than limitation, so as to thoroughly understand the embodiments of the present application. However, those skilled in the art should clearly understand that the present application can also be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to avoid unnecessary details from interfering with the description of the present application.

[0032] It should be understood that when used in the specification and appended claims of the present application, the term "comprising" indicates the presence of the described features, wholes, steps, operations, elements, and / or components, but does not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components, and / or their combinations.

[0033] In addition, in the description of the specification and appended claims of the present application, terms such as "first", "second", "third", etc. are only used for distinguishing descriptions and cannot be understood as indicating or implying relative importance.

[0034] The reference to "one embodiment" or "some embodiments" etc. described in the specification of the present application means that a specific feature, structure, or characteristic described in connection with that embodiment is included in one or more embodiments of the present application. Thus, statements such as "in one embodiment", "in some embodiments", "in other some embodiments", "in still other embodiments", etc. that appear in different places in this specification do not necessarily all refer to the same embodiment, but mean "one or more but not all embodiments", unless otherwise specifically emphasized in other ways. The terms "comprising", "including", "having", and their variants all mean "including but not limited to", unless otherwise specifically emphasized in other ways. "A plurality" means "two or more".

[0035] The present application provides an on-line measurement method for micro-structural feature parts, which can realize the on-line measurement of micro-structural features after machining micro-structural feature parts with an ultra-precision single-point diamond lathe, improve the practicability of the machine tool, and save the measurement investment cost.

[0036] The following will further describe in detail the specific implementation manners of the present application in conjunction with the accompanying drawings and embodiments. The following embodiments are used to illustrate the present application, but are not used to limit the scope of the present application.

[0037] The on-line measurement method for micro-structural feature parts provided by the embodiments of the present application includes: installing a microscopic lens on the machine tool tooling table, controlling the movement of the X-axis and Z-axis of the machine tool, observing and positioning the microscopic features of the parts, and recording the initial values of the X-axis and Z-axis coordinates of the machine tool; disassembling the microscopic lens and then installing a spectral confocal probe, and determining the adjustment values of the X-axis and Z-axis coordinates of the machine tool according to the initial values of the X-axis and Z-axis coordinates of the machine tool and the pre-determined offset values; inputting the adjustment values of the X-axis and Z-axis coordinates of the machine tool into the machine tool numerical control system, and positioning the spectral confocal probe at the microscopic features of the parts.

[0038] In some embodiments, before installing the microscopic lens on the machine tool tooling table, controlling the movement of the X-axis and Z-axis of the machine tool, observing and positioning the microscopic features of the parts, and recording the initial values of the X-axis and Z-axis coordinates of the machine tool, it further includes: respectively calibrating the microscopic lens and the spectral confocal probe with a calibration piece, and determining the offset value of the spectral confocal probe relative to the microscopic lens in the machine tool coordinate system.

[0039] In some embodiments, the step of respectively calibrating the microscopic lens and the spectral confocal probe with a calibration piece and determining the offset value of the spectral confocal probe relative to the microscopic lens in the machine tool coordinate system includes: installing the microscopic lens on the machine tool tooling table, adjusting the up and down movement of the microscopic lens, controlling the movement of the X-axis and Z-axis of the machine tool, calibrating the microscopic lens with the calibration piece, and recording the X-axis coordinate X M and the Z-axis coordinate Z M ; disassembling the microscopic lens and then installing the spectral confocal probe, adjusting the up and down movement of the spectral confocal probe, controlling the movement of the X-axis and Z-axis of the machine tool, calibrating the spectral confocal probe with the calibration piece, and recording the X-axis coordinate X P and the Z-axis coordinate Z P ; determining the offset value X offset =X P -X M , Z offset =Z P -Z M .

[0040] In some embodiments, the step of respectively calibrating the microscopic lens and the spectral confocal probe with a calibration piece and determining the offset value of the spectral confocal probe relative to the microscopic lens in the machine tool coordinate system further includes: fixing a calibration piece with a cross mark in the middle on the machine tool spindle, and adjusting the centering of the calibration piece and the machine tool spindle.

[0041] In some embodiments, the centering accuracy of the calibration piece and the machine tool spindle is better than 1 micron.

[0042] In some embodiments, the step of calibrating the microscopic lens with the calibration piece includes: aligning the microscopic lens with the cross of the calibration piece, and the image center of the microscopic lens is the cross of the calibration piece.

[0043] In some embodiments, calibrating the spectral confocal probe using a calibration piece includes: aligning the spectral confocal probe with the cross center of the calibration piece, and the measurement reading of the spectral confocal probe being in the middle of the range.

[0044] In some embodiments, after inputting the adjustment values of the X-axis and Z-axis coordinates of the machine tool into the machine tool numerical control system and positioning the spectral confocal probe behind the micro features of the part, it further includes: measuring the micro features by programming a measurement procedure, and analyzing and calculating the measurement data to obtain the height data of the micro features.

[0045] As Figures 1 to 5 shown, the on-line measurement method for micro-structured feature parts provided by the present application includes:

[0046] Calibrating the relative positions of the microscopic lens and the spectral confocal probe: The machine tool spindle 6 fixes the calibration piece 1, and adjusts the calibration piece 1 to be centered with the machine tool spindle 6; the microscopic lens 3 is installed on the machine tool workbench 7. By adjusting the up and down movement of the microscopic lens tooling, the X-axis movement of the machine tool, and the Z-axis movement of the machine tool, the microscopic lens 3 is aligned with the cross of the calibration piece 1, the image of the microscopic lens 3 is clearly displayed, and the center of the image is the cross of the calibration piece 1. Record the X-axis coordinate and Z-axis coordinate of the machine tool; the spectral confocal probe 4 is installed at the same position on the machine tool workbench 7. By adjusting the up and down movement of the spectral confocal probe tooling, the X-axis movement of the machine tool, and the Z-axis movement of the machine tool, the spectral confocal probe 4 is aligned with the cross center of the calibration piece 1, and the reading of the spectral confocal probe 4 is in the middle of the range. Record the X-axis coordinate and Z-axis coordinate of the machine tool; determine the offset value of the spectral confocal probe relative to the microscopic lens in the machine tool coordinate system.

[0047] On-line measurement of micro-structured feature parts: After the machine tool finishes machining the micro-structured feature part 2, the microscopic lens 3 is installed on the machine tool workbench 7, and the X-axis movement and Z-axis movement of the machine tool are performed to observe and position the micro features of the part, and record the initial values of the X-axis coordinate and Z-axis coordinate of the machine tool; the microscopic lens 3 is removed from the machine tool workbench 7, and the spectral confocal probe 4 is installed. According to the initial values of the X-axis coordinate and Z-axis coordinate and the offset value, input the adjustment values of the X-axis coordinate and Z-axis coordinate of the machine tool, position the spectral confocal probe 4 at the micro features of the part, measure the micro features by programming a measurement procedure, and analyze and calculate the measurement data to obtain the height data of the micro features.

[0048] The microscope lens has a large field of view and can identify the position of step features in a two-dimensional plane. With the help of the microscope lens, the spectral confocal probe can be quickly positioned at the microstructural feature position of the part. The present application calibrates the relative positions of the microscope lens and the spectral confocal probe on the machine tool. During measurement, the microscope lens is first used to observe and locate the microstructural features, and then the spectral confocal probe is used to measure the microstructural features to obtain the height data of the microstructural features. By adding a microscope lens, a spectral confocal probe, tooling, and calibration parts to the ultra-precision single-point diamond lathe, online measurement of microstructural feature parts can be achieved, saving measurement costs and improving the practicality of the ultra-precision single-point diamond lathe.

[0049] Combine the following Figures 1 to 5 The specific embodiments of the present application are described in further detail.

[0050] Example

[0051] Relative position calibration of microscope lens and spectral confocal probe: The calibration piece 1 is fixed on the machine tool spindle 6. There is a cross mark in the middle of the calibration piece 1. Adjust the calibration piece 1 to be aligned with the machine tool spindle 6. The alignment accuracy is better than 1 micron. Install the microscope lens 3 and the fixture on the measurement fixture 5 of the machine tool fixture table 7. Adjust the fixture of the microscope lens 3 to move along the Y direction of the machine tool, the X axis of the machine tool, and the Z axis of the machine tool, so that the microscope lens 3 is aligned with the cross of the calibration piece 1 until the image of the microscope lens 3 is clearly displayed and the center of the image is the cross of the calibration piece 1. Record the X-axis coordinate X of the machine tool. M , machine tool Z axis coordinate Z M Remove the microscope lens 3 and the tooling from the machine tool fixture table 7, place them at the fixing place of the machine tool outer cover, remove the spectral confocal probe 4 and the tooling from the fixing place of the machine tool outer cover, install the spectral confocal probe 4 and the tooling on the measurement fixing tooling 5 of the machine tool fixture table 7, and adjust the tooling of the spectral confocal probe 4 to move along the Y direction of the machine tool, the X-axis movement of the machine tool, and the Z-axis movement of the machine tool, so that the spectral confocal probe 4 is aligned with the cross center of the calibration piece 1, and when the measurement reading of the spectral confocal probe 4 is in the middle of the range, record the X-axis coordinate X of the machine tool. P , machine tool Z axis coordinate Z P The offset X of the spectral confocal probe 4 relative to the microscope head 3 in the machine tool coordinate system offset =X P -X M , Z offset =Z P -Z M .

[0052] On-line measurement of micro-structured feature parts: After the machine tool finishes machining the micro-structured feature part 2, a microscope lens 3 is installed on the machine tool tooling table 7. The X-axis movement and Z-axis movement of the machine tool are carried out to observe and locate the microscopic features of the part, and the X-axis coordinate X1 and Z-axis coordinate Z1 of the machine tool are recorded. The microscope lens 3 and the tooling are disassembled from the machine tool tooling table and placed at the fixed position of the machine tool outer cover. On the measurement and fixing tooling 5 of the machine tool tooling table 7, a spectral confocal probe 4 and the tooling are installed. Calculate X2 = X1 + X offset , Z2 = Z1 + Z offset， Input the X-axis positioning coordinate X2 and Z-axis positioning coordinate Z2 into the machine tool numerical control system, position the spectral confocal probe 4 at the microscopic features of the part, measure the microscopic features through the planned measurement program, and analyze and calculate the measurement data to obtain the height data of the microscopic features.

[0053] The on-line measurement method for micro-structured feature parts provided by the embodiment of the present application installs a measurement and fixing tooling, a microscope lens and the tooling, a spectral confocal probe and the tooling, and a calibration piece on an ultra-precision single-point diamond lathe. The calibration piece is used to calibrate the positions of the microscope lens and the spectral confocal probe. During measurement, the microscope lens locates the micro-structured features of the part, and the spectral confocal probe accurately measures the micro-structured features of the part. This method realizes the on-line measurement of the micro-structured features of micro-structured feature parts on an ultra-precision single-point diamond machine tool, improves the applicability of the machine tool, and saves the measurement investment cost.

[0054] It should be clear that the various embodiments in this specification are described in a progressive manner. The same or similar parts between the various embodiments can be referred to each other, and the key points of each embodiment are the differences from other embodiments. The present application is not limited to the specific structure described above and shown in the drawings. And, for the sake of brevity, the detailed description of known method technologies is omitted here.

[0055] The above-described embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the various embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. A method for online measurement of microstructure feature parts, characterized in that: include: Install a microscope lens on the machine tool table to control the movement of the X-axis and Z-axis of the machine tool, observe and locate the microscopic features of the parts, and record the initial values ​​of the X-axis and Z-axis coordinates of the machine tool; The microscope head is disassembled and the spectral confocal probe is installed, and the adjustment values ​​of the X-axis and Z-axis coordinates of the machine tool are determined according to the initial values ​​of the X-axis and Z-axis coordinates of the machine tool and the predetermined offset values; The adjustment values ​​of the machine tool's X-axis and Z-axis coordinates are input into the machine tool's numerical control system to position the spectral confocal probe on the microscopic features of the part.

2. The method for online measurement of microstructure feature parts according to claim 1, characterized in that: Before installing a microscope lens on the machine tool fixture, controlling the movement of the X-axis and Z-axis of the machine tool, observing and locating the microscopic features of the parts, and recording the initial values ​​of the X-axis and Z-axis coordinates of the machine tool, the method further includes: The microscope head and the spectral confocal probe are calibrated respectively by using the calibration parts to determine the offset value of the spectral confocal probe relative to the microscope head in the machine tool coordinate system.

3. The method for online measurement of microstructure feature parts according to claim 2, characterized in that: The method of calibrating the microscope head and the spectral confocal probe respectively by using the calibration piece to determine the offset value of the spectral confocal probe relative to the microscope head in the machine tool coordinate system includes: Install the microscope lens on the machine tool table, adjust the up and down movement of the microscope lens, control the X-axis and Z-axis movement of the machine tool, calibrate the microscope lens using the calibration piece, and record the X-axis coordinate X of the machine tool. M and the Z-axis coordinate Z M ; Remove the microscope head and install the spectral confocal probe, adjust the up and down movement of the spectral confocal probe, control the X-axis and Z-axis movement of the machine tool, calibrate the spectral confocal probe with the calibration parts, and record the X-axis coordinate X of the machine tool. P and the Z-axis coordinate Z P ; Determine the offset value X of the spectral confocal probe relative to the microscope head in the machine tool coordinate system offset =X P -X M , Z offset =Z P -Z M .

4. The method for online measurement of microstructure feature parts according to claim 3, characterized in that: The method of calibrating the microscope head and the spectral confocal probe respectively by using the calibration piece to determine the offset value of the spectral confocal probe relative to the microscope head in the machine tool coordinate system also includes: Fix a calibration piece with a cross mark in the middle on the machine tool spindle, and adjust the calibration piece to align with the machine tool spindle.

5. The method for online measurement of microstructure feature parts according to claim 4, characterized in that: The centering accuracy between the calibration part and the machine tool spindle is better than 1 micron.

6. The method for online measurement of microstructure feature parts according to claim 4, characterized in that: The method of calibrating the microscope lens by using the calibration component comprises: Align the microscope lens with the cross of the calibration piece, and the center of the image of the microscope lens is the cross of the calibration piece.

7. The method for online measurement of microstructure feature parts according to claim 4, characterized in that: The method of calibrating the spectral confocal probe by using the calibration component comprises: Align the spectral confocal probe with the center of the cross of the calibration piece, and make the measurement reading of the spectral confocal probe be in the middle of the measuring range.

8. The method for online measurement of microstructure feature parts according to claim 1, characterized in that: After inputting the adjustment values ​​of the X-axis and Z-axis coordinates of the machine tool into the numerical control system of the machine tool and positioning the spectral confocal probe on the microscopic features of the part, the method further includes: The microscopic features are measured by planning the measurement program, and the height data of the microscopic features are obtained by analyzing and calculating the measurement data.

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