Method for measuring half cavity of cell type radio frequency superconducting cavity

Abstract

The invention provides a method for measuring a half cavity of a cell type radio frequency superconducting cavity, and relates to the technical field of measurement of the half cavity of the superconducting cavity, the half cavity is installed on a predetermined measurement tool to obtain a to-be-tested piece so as to fix the half cavity, and then the to-be-tested piece is installed on a three-coordinate measurement platform to prepare for detection; the three-dimensional standard model of the half cavity is inserted in advance during detection, and a coordinate system of the three-dimensional standard model is adjusted to establish a standard; then, a coordinate system is manually and roughly established by using a half-cavity equator plane and an equator inner circle of a to-be-tested piece, and the specific position of a half cavity is found; a coordinate system is automatically and precisely established by using a half-cavity IRIS plane, an IRIS inner circle and an equator inner circle of a to-be-tested piece, the precisely established coordinate system coincides with a coordinate system of the three-dimensional standard model, finally, the size and form and location tolerance of the half-cavity of the to-be-tested piece are detected, three coordinates are adopted to carry out contact type measurement on the basic size and the inner surface profile of the half-cavity, and the measurement accuracy is improved. And the influence of half-cavity surface reflection and refraction is avoided, so that the measurement precision is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of superconducting cavity half-cavity measurement, and in particular relates to a cell-type radio frequency superconducting cavity half-cavity measurement method. Background Art

[0002] The 1.3G 9cell RF superconducting cavity consists of 56 components, including 18 half-cavities, accounting for 32% of all components. During the operation of the accelerator, the electric and magnetic fields of the half-cavity affect the acceleration direction and efficiency of the electron beam, thereby affecting the acceleration gradient Eacc of the RF superconducting cavity. At present, controlling the basic dimensions and inner surface contour of the half-cavity is an important part of manufacturing high-performance superconducting cavities. Domestic RF superconducting cavity manufacturers mostly use scanners or articulated arms to scan and measure the inner surface contour. Since the half-cavity material is high-purity niobium and the surface is relatively bright, the scanning light is affected by the reflection and refraction of the metal surface. The scanned inner surface contour value is larger than the actual contour value, resulting in large measurement errors. Summary of the invention

[0003] In view of this, the present invention provides a method for measuring a cell-type radio frequency superconducting cavity half cavity with reduced error.

[0004] The technical solution adopted by the present invention to solve its technical problem is: A method for measuring a cell-type radio frequency superconducting cavity half cavity comprises the following steps: S1: Install the half cavity on the predetermined measuring fixture to obtain the test piece; S2: Install the test piece on the three-coordinate measuring platform and prepare for testing; S3: pre-insert the three-dimensional standard model of the half cavity and adjust the coordinate system of the three-dimensional standard model; S4: Use the half-cavity equatorial plane and the inner circle of the equator of the test piece to manually build a rough coordinate system to find the half-cavity position; S5: Use the IRIS plane of the half cavity of the test piece, the IRIS inner circle and the equatorial inner circle to automatically build a precise coordinate system, and the precise coordinate system coincides with the coordinate system of the 3D standard model; S6: Check the size, shape and position tolerance of the half cavity of the inspected part.

[0005] Preferably, in S1, the predetermined measuring tool includes a support plate, a mounting and fixing component, and a circumferential fixing component. The mounting and fixing component and the circumferential fixing component are located on the support plate, the circumferential fixing component is located on the side of the mounting and fixing component, the bottom of the mounting and fixing component is connected to the support plate, the half cavity is embedded in the mounting and fixing component, and the circumferential fixing component can be pressed on the half cavity.

[0006] Preferably, the mounting and fixing assembly includes a support member and a fixing ring, wherein there are at least two support members, the support members are evenly arranged along the bottom of the fixing ring, one end of the support member is connected to the support plate, and the other end of the support member is connected to the bottom of the fixing ring.

[0007] Preferably, the bottom of the half cavity can extend out of the bottom of the fixing ring.

[0008] Preferably, the width and thickness of the support member are 20 mm-25 mm.

[0009] Preferably, the length and width of the support plate are smaller than those of the three-coordinate measurement platform.

[0010] Preferably, there are two circumferential fixing components, which are located on both sides of the half cavity, and the angle between the two circumferential fixing components is 180°. The circumferential fixing components include a fixing rod, a lifting rod, and an elastic pressure plate. One end of the fixing rod is connected to the surface of the support plate, and the other end of the fixing rod is connected to the lifting rod. The elastic pressure plate is rotatably connected to the lifting rod. The lifting rod can be lifted and lowered along the length direction of the fixing rod, and the elastic pressure plate can be pressed on the half cavity.

[0011] Preferably, in S2, there are multiple pieces to be tested.

[0012] Preferably, the cell-type radio frequency superconducting cavity half-cavity measurement method further includes S7, wherein S7: performing inner surface contour detection on the half-cavity of the detected component.

[0013] Preferably, the inner surface contour detection of the half cavity is specifically as follows: using the three-coordinate automatic point measurement function to collect points on the inner contour surface of the half cavity, and after the point collection is completed, all points are fitted into a feature group, and the surface contour of the plane fitting feature group is completed, that is, the inner surface contour detection is completed.

[0014] Compared with the prior art, the present invention has the following beneficial effects: The present invention provides a method for measuring a cell-type radio frequency superconducting cavity half cavity. The method comprises the following steps: installing the half cavity on a predetermined measuring fixture to obtain a test piece, fixing the half cavity, and then installing the test piece on a three-coordinate measuring platform to prepare for detection. During detection, a three-dimensional standard model of the half cavity is pre-inserted, and the coordinate system of the three-dimensional standard model is adjusted to establish a standard. Then, the equatorial plane and the equatorial inner circle of the half cavity of the test piece are used to manually roughly construct a coordinate system to find the specific position of the half cavity. Then, the IRIS plane, the IRIS inner circle and the equatorial inner circle of the half cavity of the test piece are used to automatically and precisely construct a coordinate system, and the precisely constructed coordinate system coincides with the coordinate system of the three-dimensional standard model. Finally, the size and shape and position tolerance of the half cavity of the test piece are detected, so that repeated positioning is not required during the half cavity detection process, and the three-coordinate method is used to perform contact measurement on the basic size and inner surface contour of the half cavity, which will not be affected by the reflection and refraction of the half cavity surface, thereby improving the measurement accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the structure of the predetermined measuring tool.

[0016] Figure 2 This is a schematic diagram of the installation of the test piece and the three-coordinate measurement platform.

[0017] Figure 3 This is a schematic diagram of the structure of the predetermined measuring tool from another angle.

[0018] Figure 4 Schematic diagram of the rough coordinate system of the half cavity.

[0019] Figure 5 Schematic diagram of the half-cavity precision coordinate system.

[0020] In the figure: a predetermined measuring tool 10, a support plate 100, an installation and fixing assembly 200, a support member 210, a fixing ring 220, a circumferential fixing assembly 300, a fixing rod 310, a lifting rod 320, an elastic pressure plate 330, a half cavity 20, and a three-coordinate measurement platform 30. DETAILED DESCRIPTION

[0021] The technical solutions and technical effects of the embodiments of the present invention are further described in detail below in conjunction with the accompanying drawings of the present invention.

[0022] A method for measuring a cell-type radio frequency superconducting cavity half cavity 20 comprises the following steps: S1: Install the half chamber 20 as follows: Figure 1 On the predetermined measuring tool 10 shown, a piece to be tested is obtained; S2: Mount the test piece on the three-coordinate measuring platform 30, such as Figure 2 As shown, prepare for testing; S3: pre-insert the three-dimensional standard model of the half cavity 20 and adjust the coordinate system of the three-dimensional standard model; S4: Use the equatorial plane of the half cavity 20 of the test piece and the inner circle of the equator to manually build a coordinate system to find the position of the half cavity 20; Specifically, the workpiece to be measured is placed on the three-coordinate measuring platform, and the equatorial plane of the half cavity 20 is first manually measured. The coordinate system is roughly established on the inner circle of the equator so that the three-coordinate measuring machine can find the position of the half cavity 20. Figure 4 As shown; S5: Use the 20IRIS plane of the half cavity of the test piece, the IRIS inner circle and the equatorial inner circle to automatically build a precise coordinate system, and the precise coordinate system coincides with the coordinate system of the 3D standard model; Specifically, the machined datum of the half cavity 20 is the IRIS plane. To improve the measurement accuracy, the automatic measurement datum is consistent with the machined datum. The IRIS plane of the half cavity 20 of the test piece, the IRIS inner circle, and the equatorial inner circle are automatically and precisely constructed into a coordinate system, such as Figure 5 As shown. Since the surface contour of the workpiece needs to be evaluated during dimensional evaluation, the precision-built coordinate system coincides with the coordinate system of the three-dimensional standard model; S6: Check the size, shape and position tolerance of the half cavity 20 of the inspected part.

[0023] Compared with the prior art, the present invention has the following beneficial effects: The present invention provides a method for measuring a cell-type radio frequency superconducting cavity half cavity 20. The method comprises the following steps: installing the half cavity 20 on a predetermined measuring fixture 10 to obtain a test piece, fixing the half cavity 20, and then installing the test piece on a three-coordinate measuring platform 30 to prepare for testing. During testing, a three-dimensional standard model of the half cavity 20 is pre-inserted, and the coordinate system of the three-dimensional standard model is adjusted to establish a standard. Then, the equatorial plane and the equatorial inner circle of the half cavity 20 of the test piece are used to manually roughly construct a coordinate system to find the specific position of the half cavity 20. Then, the IRIS plane, the IRIS inner circle and the equatorial inner circle of the half cavity 20 of the test piece are used to automatically and precisely construct a coordinate system, and the precisely constructed coordinate system coincides with the coordinate system of the three-dimensional standard model. Finally, the size and shape and position tolerance of the half cavity 20 of the test piece are tested, so that repeated positioning is not required during the testing process of the half cavity 20, and the three-coordinate is used to perform contact measurement on the basic size and inner surface contour of the half cavity 20, which will not be affected by the reflection and refraction of the surface of the half cavity 20, thereby improving the measurement accuracy.

[0024] like Figure 1 , 2As shown in , 3, further, in S1, the predetermined measuring tool 10 includes a support plate 100, a mounting and fixing component 200, and a circumferential fixing component 300, the support plate 100 is located on the three-coordinate measurement platform 30, the mounting and fixing component 200 and the circumferential fixing component 300 are located on the support plate 100, the circumferential fixing component 300 is located on the side of the mounting and fixing component 200, the support plate 100 is connected to the upper surface of the three-coordinate measurement platform 30, the bottoms of the mounting and fixing component 200 and the circumferential fixing member are respectively connected to the support plate 100, the half cavity 20 is embedded in the mounting and fixing component 200, the circumferential fixing component 300 can be pressed on the half cavity 20, the half cavity 20 is fixed by the mounting and fixing component 200 and the circumferential fixing component 300 to prevent the half cavity 20 from tilting and rotating, and the half cavity 20 is lifted to a certain height by the mounting and fixing component 200, so that during detection, the measuring equipment can detect the bottom and the inside of the half cavity 20.

[0025] Furthermore, the installation and fixing assembly 200 includes a support member 210 and a fixing ring 220. There are at least two support members 210. The support members 210 are evenly arranged along the bottom of the fixing ring 220. One end of the support member 210 is connected to the support plate 100, and the other end of the support member 210 is connected to the bottom of the fixing ring 220. The fixing ring 220 is adapted to the bottom of the half cavity 20. The support member 210 lifts the half cavity 20 to a certain height, and the fixing ring 220 fixes the half cavity 20 to prevent the half cavity 20 from moving in the horizontal and vertical directions. On the one hand, the measurement datum of the half cavity 20 is consistent with the processing datum, so that the measurement result is consistent with the machining measurement result; on the other hand, On one hand, since the height of the IRIS inner diameter straight edge of the half cavity 20 is only 0.5 mm, and the smallest ruby ​​stylus ball in the three-coordinate device has a diameter of 1 mm, if the half cavity 20 is not raised by the support member 210 and the fixing ring 220, the center of the ruby ​​stylus ball cannot accurately measure the IRIS inner diameter straight edge during measurement, which will result in a larger measured value; on the other hand, the half cavity 20 is installed in the fixing ring 220 to form a part to be detected, and there is no need to repeatedly and accurately position the half cavity 20. The half cavity 20 is installed in the fixing ring 220 to form a part to be detected. After the measurement is completed, the fixing assembly 200 is fixed, the elastic pressure plate is removed, and the next half cavity is replaced for automatic measurement. There is no need to perform manual positioning measurement, and batch replacement detection can be achieved.

[0026] Specifically, the number of the support members 210 may be three or four, the support members 210 are cylindrical or prismatic, and the fixing ring 220 is a hollow disc.

[0027] Furthermore, the bottom of the half cavity 20 can extend out of the bottom of the fixing ring 220, so that during measurement, the fixing ring 220 does not affect the detection of the ruby ​​stylus ball being measured, and the center of the ruby ​​stylus ball can accurately measure the straight edge of the IRIS inner diameter, so that the measurement value is accurate.

[0028] Furthermore, the width and thickness of the support member 210 are 20 mm-25 mm to prevent the support member 210 from affecting the measurement.

[0029] Furthermore, the length and width of the support plate 100 are smaller than those of the three-coordinate measurement platform 30 .

[0030] Furthermore, there are two circumferential fixing components 300, which are located on both sides of the half cavity 20, and the angle between the two circumferential fixing components 300 is 180°. The circumferential fixing components 300 include a fixing rod 310, a lifting rod 320, and an elastic pressure plate 330. One end of the fixing rod 310 is connected to the surface of the support plate 100, and the other end of the fixing rod 310 is connected to the lifting rod 320. The elastic pressure plate 330 is rotatably connected to the lifting rod 320. The lifting rod 320 can be lifted and lowered along the length direction of the fixing rod 310. The elastic pressure plate 330 can be pressed on the half cavity 20, and different models of half cavities 20 can be pressed, with good adaptability.

[0031] Specifically, the interior of the fixed rod 310 is hollow and has threads, and the outer surface of the lifting rod 320 is provided with external threads. The lifting rod 320 and the fixed rod 310 are threadedly matched to achieve the lifting and lowering of the lifting rod 320 in the fixed rod 310.

[0032] Furthermore, in S2, there are multiple pieces to be tested, and batch testing can be performed.

[0033] Furthermore, the method for measuring the cell-type radio frequency superconducting cavity half cavity 20 also includes S7, wherein S7: performing inner surface contour detection on the half cavity 20 of the detected object.

[0034] Furthermore, the inner surface contour detection of the half cavity 20 is specifically as follows: using the three-coordinate automatic point measurement function, points are collected on the inner contour surface of the half cavity 20. After the point collection is completed, all points are fitted into a feature group, and the surface contour of the plane fitting feature group is completed, that is, the inner surface contour detection is completed, and the inner contour of the surface is measured by using a ruby ​​stylus touch measurement method. Compared with the previous method without a predetermined measuring tool 10, the position of each half cavity placed on the three-coordinate measurement platform 30 cannot be fixed, and the measurement efficiency can be improved by 50%.

[0035] What is disclosed above is only a preferred embodiment of the present invention, which certainly cannot be used to limit the scope of rights of the present invention. A person skilled in the art can understand that all or part of the processes of the above embodiments and equivalent changes made according to the claims of the present invention still fall within the scope of the invention.

Claims

1. A method for measuring a cell-type radio frequency superconducting cavity half cavity, characterized in that: The following steps are involved: S1: Install the half cavity on the predetermined measuring fixture to obtain the test piece; S2: Install the test piece on the three-coordinate measuring platform and prepare for testing; S3: pre-insert the three-dimensional standard model of the half cavity and adjust the coordinate system of the three-dimensional standard model; S4: Use the half-cavity equatorial plane and the inner circle of the equator of the test piece to manually build a rough coordinate system to find the half-cavity position; S5: Use the IRIS plane of the half cavity of the test piece, the IRIS inner circle and the equatorial inner circle to automatically build a precise coordinate system, and the precise coordinate system coincides with the coordinate system of the 3D standard model; S6: Check the size, shape and position tolerance of the half cavity of the inspected part.

2. The method for measuring a cell-type radio frequency superconducting cavity half cavity according to claim 1, characterized in that: In S1, the predetermined measuring tool includes a support plate, a mounting and fixing component, and a circumferential fixing component. The mounting and fixing component and the circumferential fixing component are located on the support plate, the circumferential fixing component is located on the side of the mounting and fixing component, the bottom of the mounting and fixing component is connected to the support plate, the half cavity is embedded in the mounting and fixing component, and the circumferential fixing component can be pressed on the half cavity.

3. The method for measuring a cell-type radio frequency superconducting cavity half cavity as claimed in claim 2, characterized in that: The mounting and fixing assembly includes a support member and a fixing ring. There are at least two support members, and the support members are evenly arranged along the bottom of the fixing ring. One end of the support member is connected to the support plate, and the other end of the support member is connected to the bottom of the fixing ring.

4. The method for measuring a cell-type radio frequency superconducting cavity half cavity as claimed in claim 3, characterized in that: The bottom of the half chamber can extend beyond the bottom of the fixing ring.

5. The method for measuring a cell-type radio frequency superconducting cavity half cavity as claimed in claim 3, characterized in that: The width and thickness of the support member are 20mm-25mm.

6. The method for measuring a cell-type radio frequency superconducting cavity half cavity according to claim 3, characterized in that: The length and width of the support plate are smaller than the three-coordinate measurement platform.

7. The method for measuring a cell-type radio frequency superconducting cavity half cavity according to claim 2, characterized in that: There are two circumferential fixing components, which are located on both sides of the half cavity, and the angle between the two circumferential fixing components is 180°. The circumferential fixing components include a fixing rod, a lifting rod, and an elastic pressure plate. One end of the fixing rod is connected to the surface of the support plate, and the other end of the fixing rod is connected to the lifting rod. The elastic pressure plate is rotatably connected to the lifting rod. The lifting rod can be lifted and lowered along the length direction of the fixing rod, and the elastic pressure plate can be pressed on the half cavity.

8. The method for measuring a cell-type radio frequency superconducting cavity half cavity according to claim 1, characterized in that: In S2, there are multiple pieces to be tested.

9. The method for measuring a cell-type radio frequency superconducting cavity half cavity according to claim 1, characterized in that: The cell-type radio frequency superconducting cavity half-cavity measurement method further includes S7, wherein S7: performing inner surface contour detection on the half-cavity of the detected component.

10. The method for measuring a cell-type radio frequency superconducting cavity half cavity according to claim 9, characterized in that: The inner surface contour detection of the half cavity is specifically as follows: using the three-coordinate automatic point measurement function to collect points on the inner contour surface of the half cavity, and after the point collection is completed, all points are fitted into a feature group, and the surface contour of the plane fitting feature group is completed, that is, the inner surface contour detection is completed.

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