Method for fast measurement and adjustment of the axis of the hole in the target seating mechanism and in the inductive cavity

Abstract

The application provides a kind of fast measurement adjustment method for centering target seat mechanism and the axis of hole in induction cavity, to solve the technical problems of the existing hardware supporting facilities complexity, operation process is complicated and the low work efficiency of the axis of hole in induction cavity measurement method based on "laser + centering device + photosensitive diode + reflecting plane mirror". The application designs a kind of centering target seat mechanism with dial gauge, rotating rod, fine adjustment top screw and other components based on laser tracker measurement technology, which places the target seat at the center point of the hole in the induction cavity with high precision, and then uses laser tracker to measure the center point coordinates of the induction cavity insertion part; through two sets of the same above-mentioned centering target seat mechanism, the center point coordinates of the front and rear end faces of the induction cavity can be measured simultaneously, so as to realize the fast measurement of the axis of hole in induction cavity.

Description

Technical Field

[0001] This invention relates to the measurement of the central axis of the induction cavity bore, specifically to a centering target base mechanism and a rapid measurement and adjustment method for the central axis of the induction cavity bore. Background Technology

[0002] Currently, large-scale pulsed power devices employing Induced Voltage Superposition (IVA) technology feature multi-stage series-connected induction cavities. Each induction cavity is a complex, disc-shaped assembly with an inner hole. The induction cavities are fixed to a support beam mounted with guide rails. During assembly, adjacent induction cavities require horizontal alignment and insertion, with the insertion point being a clearance-fit coaxial structure. To ensure device performance, the central axis of each induction cavity should coincide with the theoretical central axis during series assembly. Therefore, during the assembly of multi-stage series-connected induction cavities, it is crucial not only to ensure the coaxial accuracy at the insertion points of adjacent induction cavities but also to accurately measure and adjust the central axis of the inner hole of the induction cavity. This ensures the alignment accuracy of the overall central axis relative to the theoretical central axis after multi-stage series-connected assembly, thereby controlling cumulative errors.

[0003] Considering the large size and multiple stages of the induction cavity, the workload of measurement and adjustment is substantial. Achieving both accurate and rapid measurement is crucial for improving the efficiency of device construction and implementation. Existing methods for measuring the centerline of the induction cavity's inner hole, based on a "laser + centering device + photodiode + reflecting plane mirror," suffer from complex hardware, cumbersome operation, and low efficiency, hindering practical application. Furthermore, no literature reports have been found on the efficient measurement and adjustment of the centerline when multiple induction cavities are assembled in series using other devices and methods. Summary of the Invention

[0004] The purpose of this invention is to solve the technical problems of complex hardware facilities, cumbersome operation process and low work efficiency of the existing method for measuring the centerline of the induction cavity hole based on "laser + centering device + photodiode + reflecting plane mirror". The invention provides a method for rapid measurement and adjustment of the centering target base mechanism and the centerline of the induction cavity hole.

[0005] The inventive concept of this invention is as follows: Based on laser tracker measurement technology, a centering target holder mechanism is designed, including components such as a dial indicator, a rotating rod, and a fine-tuning set screw. This mechanism can place the target holder at the center point of the inner hole of the sensing cavity to be measured with high precision, thereby allowing the laser tracker to measure the center point coordinates of the parts at the insertion point of the sensing cavity. By using two identical sets of the above-mentioned centering target holder mechanisms, the center point coordinates of the front and rear end faces of the sensing cavity can be measured simultaneously, thereby achieving rapid measurement and adjustment of the central axis of the inner hole of the sensing cavity.

[0006] To achieve the above objectives and complete the above inventive concept, the technical solution proposed by this invention is as follows:

[0007] A target positioning mechanism is characterized by comprising a frame, a target base, at least one rotating rod sleeve, a rotating rod, a dial indicator, four sets of adjustment components, and at least three locking screws.

[0008] The frame is a long strip structure with connecting through holes at both ends for connecting to the object to be tested, such as a sensing cavity; a mounting through hole is provided at the center of the frame.

[0009] The target holder includes a hollow cylinder and a mounting flange disposed on the outer wall of the hollow cylinder; the hollow cylinder passes through a mounting through hole and is fastened to one side of the frame by the mounting flange;

[0010] One end of the hollow cylinder is configured as an inner conical surface, and a magnet is provided on the inner side of the inner conical surface to attract the laser tracker target onto the inner conical surface.

[0011] The rotating rod sleeve is fitted onto the outer wall of the hollow cylinder, and the inner wall of the rotating rod sleeve is tightly fitted with the outer wall of the hollow cylinder, so that the rotating rod sleeve can rotate relative to the hollow cylinder.

[0012] One end of the rotating rod is threaded to the outer wall of the rotating rod sleeve, and the other end is connected to the dial indicator;

[0013] The adjustment assembly includes fine-tuning side plates and fine-tuning set screws; four fine-tuning side plates are symmetrically fixed on the frame in pairs, and all four fine-tuning side plates are set opposite to the outer wall of the mounting flange; threaded holes are opened on the fine-tuning side plates at the positions corresponding to the outer wall of the mounting flange, and the four fine-tuning set screws pass through the threaded holes on the corresponding fine-tuning side plates and abut against the outer wall of the mounting flange.

[0014] The frame is provided with at least three through holes in the circumference corresponding to the mounting flange position. The diameter of the through holes is larger than the diameter of the locking screws. Multiple locking screws pass through the corresponding through holes of the frame and are threaded to the mounting flange for fine-tuning and locking the target seat.

[0015] Furthermore, the adjustment assembly also includes four fine-tuning locking nuts;

[0016] The four fine-tuning locking nuts are used to install on the corresponding fine-tuning set screws and tighten them after the fine-tuning set screws have been adjusted.

[0017] Furthermore, the four fine-tuning side plates are symmetrically fixed in pairs in the length and width directions of the skeleton. The two fine-tuning side plates fixed in the length direction of the skeleton are respectively installed on the surface of the skeleton by two fixing screws, and the two fine-tuning side plates fixed in the width direction of the skeleton are respectively installed on the two side walls of the skeleton by two fixing screws.

[0018] The skeleton has two fine-tuning set screws with corresponding length directions and strip-shaped through holes along the length direction.

[0019] Furthermore, the number of the rotating rod sleeves is two;

[0020] The two rotating rod sleeves are respectively fitted onto the outer walls of the hollow cylinders on both sides of the mounting flange;

[0021] One end of the rotating rod is threadedly connected to the outer wall of any rotating rod sleeve;

[0022] The magnet is detachably mounted on the inner conical surface of the hollow cylinder.

[0023] Furthermore, it also includes fixed structures;

[0024] The fixing structure includes a first structural component, a second structural component, and two dial indicator fixing screws;

[0025] The first structural member has a first semi-circular notch and a second semi-circular notch axially opened on one side, and the second structural member has a first semi-circular notch and a second semi-circular notch axially opened on the corresponding position on one side. The two first semi-circular notches are connected to form a first through hole that matches the outer diameter of the rotating rod, and the two second semi-circular notches are connected to form a second through hole that matches the outer diameter of the bushing of the dial indicator.

[0026] The first structural component has radial through holes at both ends, and the second structural component has radial threaded holes at the corresponding positions of the radial through holes;

[0027] One end of the rotating rod passes through the first through hole, the bushing of the dial indicator passes through the second through hole, and the two dial indicator fixing screws pass through the radial through hole of the first structural component and are threadedly connected to the radial threaded hole of the second structural component in sequence.

[0028] Furthermore, it also includes two retaining rings;

[0029] The hollow cylinder has retaining grooves at both ends of its outer wall, which are located immediately adjacent to the outer sides of the two rotating rod sleeves.

[0030] The two retaining rings are installed in corresponding retaining ring slots, and their inner end faces abut against the outer end faces of the corresponding rotating rod sleeves.

[0031] Furthermore, reinforcing ribs are provided on both sides of the frame;

[0032] The positions of the four fine-tuning screws on the outer wall of the mounting flange are set as a plane.

[0033] Furthermore, both the frame and the rotating rod are made of LY12 aluminum alloy.

[0034] The target holder, rotating rod sleeve, and fine-tuning side plate are all made of 304 stainless steel.

[0035] Meanwhile, the present invention also provides a rapid measurement and adjustment method for the central axis of the induction cavity bore, which adopts the above-mentioned centering target base mechanism, and its special feature is that it includes the following steps:

[0036] Step 1: Establish a control network. Use a laser tracker to measure the coordinates of the network points of the control network, and backfit the measured network point coordinates to obtain the device coordinate system where the sensing cavity is located. The control network is a network composed of multiple fixed measurement points set around the sensing cavity.

[0037] Step 2: Assemble two sets of the above-mentioned centering target base mechanisms. The rotating rod of one set of centering target base mechanisms is installed on the rotating rod sleeve on the front side of the mounting flange, and the rotating rod of the other set of centering target base mechanisms is installed on the rotating rod sleeve on the rear side of the mounting flange. The two sets of centering target base mechanisms are respectively vertically installed on the front and rear insertion parts of the sensing cavity to be tested, and the dial indicators of the two sets of centering target base mechanisms are facing the direction of the inner hole of the sensing cavity to be tested.

[0038] Step 3: Adjust the relative positions of the two dial indicators and the corresponding rotating rods until the measuring heads of the two dial indicators are in contact with the front and rear connectors in the inner hole of the sensing cavity under test at the center of their stroke.

[0039] Step 4: Calibrate the dial gauges of the two sets of centering target base mechanisms;

[0040] Step 5: The laser tracker target is attached to the two target holders one after the other, and then the coordinates of the two center points of the front and rear end faces of the sensing cavity under test in the device coordinate system are measured by the laser tracker.

[0041] Step 6: Connect the coordinates of the two center points of the front and rear end faces of the induction cavity under test in the device coordinate system and record it as the measured central axis of the induction cavity under test. According to the offset of the measured central axis of the induction cavity under test relative to its theoretical central axis, adjust the four support adjustment modules of the induction cavity under test. At the same time, use a laser tracker to measure cyclically until the measured central axis of the induction cavity under test coincides with its theoretical central axis, and complete the measurement of the central axis of the induction cavity under test.

[0042] Furthermore, step 4 specifically involves:

[0043] Loosen the locking screws of the two sets of centering target base mechanisms, and then adjust the corresponding fine adjustment screws so that when the dial indicator rotates one revolution along the target base, the change in the displacement scale indicated on the dial indicator dial does not exceed the set threshold. At this time, tighten the locking screws and fine adjustment locking nuts to complete the calibration of the dial indicator.

[0044] The advantages of this invention compared to the prior art are as follows:

[0045] 1. The centering target holder mechanism provided by this invention cleverly combines a mechanical centering mechanism with laser tracker measurement technology, which can quickly and effectively install the centering target holder mechanism on the central axis of the inner hole of the sensing cavity to be measured; at the same time, the target holder is set as a hollow structure, which can provide an optical path channel for the laser tracker when measuring the center point of the other end of the sensing cavity. Two sets of centering target holder mechanisms can be installed on the front and rear end faces of the sensing cavity at the same time to carry out measurement, which effectively improves the measurement efficiency; the centering target holder mechanism of this invention has a simple composition and high measurement accuracy and efficiency, and can be widely used in other similar applications.

[0046] 2. The centering target base mechanism provided by the present invention can be equipped with dial gauges on both the front and rear sides. With simple switching, the center point of the other end of the sensing cavity can be measured using the same set of mechanisms, which improves the versatility and standardization of the centering target base mechanism.

[0047] 3. The centering target base mechanism provided by the present invention can measure the outer circle or inner hole of the part by changing the inner and outer orientation of the dial indicator head when connecting the dial indicator and the rotating rod, thereby improving the adaptability to the measurement object.

[0048] 4. The present invention provides a rapid measurement and adjustment method for the central axis of the inner hole of the sensing cavity. It only requires measuring the coordinates of two center points on the front and rear end faces of the inner hole of the sensing cavity to be measured. Compared with the traditional measurement method based on laser tracker, which requires measuring multiple points on the cylindrical surface of the inner hole and performing fitting calculations in software, the measurement method of the present invention is more direct and efficient.

[0049] 5. The present invention provides a rapid measurement and adjustment method for the central axis of the induction cavity hole. In terms of hardware, it only requires a target positioning mechanism and a laser tracker. It does not require the complex hardware of similar measurement methods such as lasers, target positioning devices, photodiodes, and reflectors. The system composition and operation process are simpler. Attached Figure Description

[0050] Figure 1 This is a schematic diagram of an embodiment of the target centering mechanism of the present invention;

[0051] Figure 2 for Figure 1 A partial sectional view along the middle HH;

[0052] Figure 3 This is a partial structural diagram of the skeleton in an embodiment of the target centering mechanism of the present invention;

[0053] Figure 4 This is a schematic diagram of the target holder structure in one embodiment of the target holder mechanism of the present invention;

[0054] Figure 5 This is a partial front view of an embodiment of the centering target holder mechanism of the present invention;

[0055] Figure 6 This is a partial rear view of an embodiment of the centering target holder mechanism of the present invention;

[0056] Figure 7 This is a schematic diagram of the rotating rod, the fixing structure, and the dial gauge in one embodiment of the target positioning mechanism of the present invention;

[0057] Figure 8 This is a schematic diagram illustrating the principle of an embodiment of a rapid measurement and adjustment method for the central axis of an induction cavity bore according to the present invention;

[0058] Figure 9 for Figure 8 A magnified view of a portion of the image.

[0059] The specific labeling in the attached diagram is as follows:

[0060] 1-Frame, 101-Connecting through hole, 102-Mounting through hole, 103-Through hole, 104-Strip through hole; 2-Target seat, 201-Hollow cylinder, 202-Mounting flange, 203-Snap ring groove; 3-Rotating rod sleeve; 4-Rotating rod; 5-Dial indicator, 51-Dial, 52-Point, 53-Sleeve, 54-Measuring head; 6-Fixing structure, 61-First structural component, 62-Second structural component; 7-Dial indicator fixing screw; 8-Locking screw; 9-Locking washer; 10-Fine adjustment side plate; 11-Fixing screw; 12-Fine adjustment set screw; 13-Fine adjustment lock nut; 14-Magnet; 15-Snap ring; 16-Laser tracker; 17-Laser tracker target; 18-Test sensing cavity; 19-Support adjustment module; 20-Device coordinate system; 21-Centering target seat mechanism. Detailed Implementation

[0061] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0062] This invention addresses the problem of centerline measurement during the assembly of multi-stage series-connected induction cavities, proposing a centering target base mechanism and a method for rapid measurement and adjustment of the centerline of the induction cavity's inner hole based on this mechanism. The induction cavity is a large-sized, hollow, disc-shaped complex assembly; in this example, the outer diameter of the induction cavity to be measured is approximately 3 meters, and the inner diameter is approximately 0.8 meters. The cylindrical surface of the inner hole of the induction cavity is composed of three insertable parts: front, middle, and rear. The front insertable part is used to mate with the rear insertable part of the preceding induction cavity, and the rear insertable part is used to mate with the front insertable part of the following induction cavity. Therefore, it is necessary to determine the centerline of the induction cavity to complete the front-to-back insertion with the preceding and following induction cavities.

[0063] like Figure 1 , Figure 2 As shown, a target positioning mechanism includes a frame 1, a target base 2, two rotating rod sleeves 3, a rotating rod 4, a dial indicator 5, four sets of adjustment components, and four locking screws 8.

[0064] like Figure 3 As shown, the frame 1 is the main frame of the target mounting mechanism, and is an overall elongated structure. Its length is determined according to the structure to be measured. To reduce weight, the frame 1 is made of LY12 aluminum alloy. Threaded holes are provided on both the front and rear insertion parts inside the sensing cavity 18. Connecting through holes 101 are provided at both ends of the frame 1, allowing screws to pass through the corresponding connecting through holes 101 and connect and fix to the object to be measured, for example, to the threaded holes of the front or rear insertion parts of the sensing cavity 18. Simultaneously, a mounting through hole 102 is provided at the center of the frame 1 for mounting and fixing the target mount 2.

[0065] like Figure 4 As shown, the target holder 2 is the core component of the target holder mechanism. It includes a hollow cylinder 201 and a mounting flange 202 disposed on the outer wall of the hollow cylinder 201. The hollow cylinder 201 and the mounting flange 202 are an integrated structure, both made of 304 stainless steel. The hollow cylinder 201 passes through the mounting through hole 102 of the frame 1 and is secured to one side of the frame 1 by the mounting flange 202 on the outer wall of the hollow cylinder 201. The frame 1 has four through holes 103 circumferentially arranged corresponding to the positions of the mounting flange 202. The mounting flange 202 has four threaded blind holes corresponding to the positions of the four through holes 103. The diameter of the through holes 103 needs to be larger than the diameter of the locking screw 8 to provide clearance for position adjustment. Two of the four locking screws 8 pass through the locking washer 9 and two through holes 103 at any diagonal position on the frame 1, respectively, and are threaded into the corresponding threaded holes on the mounting flange 202. The remaining two locking screws 8 pass through the other two through holes 103 on the frame 1 and are threaded into the corresponding threaded holes on the mounting flange 202. This is used to achieve the connection and fixation between the target seat 2 and the frame 1 after fine adjustment. The locking washer 9 is a strip-shaped perforated part made of 304 stainless steel.

[0066] like Figure 5 As shown, each adjustment assembly includes a fine-tuning side plate 10, two fixing screws 11, a fine-tuning set screw 12, and a fine-tuning locking nut 13. The four fine-tuning side plates 10 are symmetrically fixed in pairs along the length and width directions of the frame 1. Specifically, the fine-tuning side plate 10 is a cuboid structure with through holes and threaded holes, made of 304 stainless steel. The two fine-tuning side plates 10 fixed along the length direction of the frame 1 are respectively mounted on the surface of the frame 1 using two fixing screws 11, and the two fine-tuning side plates 10 fixed along the width direction of the frame 1 are respectively mounted on the two side walls of the frame 1 using two fixing screws 11. Simultaneously, all four fine-tuning side plates 10 are positioned opposite the outer wall of the mounting flange 202, and the four fine-tuning set screws 12 pass through the threaded holes on the corresponding fine-tuning side plates 10 and abut against the outer wall of the mounting flange 202, thereby achieving planar position adjustment of the target seat 2. Preferably, the fine-tuning set screw 12 is a standard knurled flat-head screw, which is convenient for manual adjustment and improves the efficiency of the adjustment operation. Correspondingly, the positions of the four fine-tuning set screws 12 on the outer wall of the mounting flange 202 are set as a plane to improve the adjustment accuracy. Four fine-tuning locking nuts 13 are used to install on the corresponding fine-tuning set screws 12 and tighten them after the fine-tuning set screws 12 have been adjusted.

[0067] In addition, in this embodiment, the two fine-adjustment screws 12 on the skeleton 1 corresponding to the length direction are provided with strip-shaped through holes 104 along the length direction, which facilitates the adjustment of the fine-adjustment screws 12 by fingers and conforms to ergonomic design. Reinforcing ribs are also designed on both sides of the skeleton 1 to improve rigidity and reduce deformation.

[0068] One end of the hollow cylinder 201 of the target holder 2 is configured as an inner conical surface, serving as the adsorption mating surface for the laser tracker target 17. A detachable magnet 14 is provided on the inner side of the inner conical surface. The magnet 14 is a strongly magnetic circular metal plate, used to firmly adsorb the laser tracker target 17 onto the inner conical surface using its strong magnetism. The internal space of the hollow cylinder 201 provides the optical path for the laser tracker, allowing measurement of the laser tracker target 17 on the other side without disassembling the target holder mechanism on that side, only by removing the magnet 14, effectively improving measurement efficiency. Specifically, when it is necessary to measure the center point of the other side of the sensing cavity 18 under test, the magnet 14 on the current side can be removed, thereby restoring the laser path within the inner hole of the sensing cavity 18 under test.

[0069] like Figure 6As shown, the rotating rod sleeve 3 is a cylindrical structure made of 304 stainless steel. Two rotating rod sleeves 3 are respectively fitted onto the outer walls of the hollow cylinder 201 on both sides of the mounting flange 202, with a tight clearance fit between the inner wall of the rotating rod sleeve 3 and the outer wall of the hollow cylinder 201 to achieve circumferential rotation of the rotating rod sleeve 3 relative to the hollow cylinder 201. At both ends of the outer wall of the hollow cylinder 201 of the target seat 2, adjacent to the outer sides of the two rotating rod sleeves 3, are respectively provided with retaining spring grooves 203. The retaining springs 15 are standard parts, and the two retaining springs 15 are installed in the corresponding retaining spring grooves 203, with their inner end faces abutting against the corresponding outer end faces of the rotating rod sleeves 3 to prevent axial movement and slippage of the rotating rod sleeves 3.

[0070] The rotating rod 4 is a long cylindrical structure with a thread at one end, made of LY12 aluminum alloy. Its length is determined according to the inner diameter of the sensing cavity 18 to be measured. The ends of the two rotating rod sleeves 3 away from the mounting flange 202 are respectively provided with threaded holes. The outer wall of one end of the rotating rod 4 is provided with external threads for threaded connection with one of the two rotating rod sleeves 3 under different measurement conditions. Its other end is connected to the dial indicator 5 through the fixing structure 6.

[0071] like Figure 7 As shown, the dial indicator 5 is a standard measuring tool product, which includes a dial 51, a needle 52 mounted on the dial 51, a bushing 53 mounted on the side of the dial 51, and a measuring head 54 that is internally connected to the needle 52 and coaxially passes through the bushing 53. When the measuring head 54 extends or retracts, the needle 52 will change its scale accordingly. If the measuring head 54 moves 1 mm, the measuring accuracy is 0.01 mm per revolution of the needle 52. In this embodiment, the measuring range is 10 mm. The fixing structure 6 includes a first structural component 61, a second structural component 62, and two dial indicator fixing screws 7. Both the first structural component 61 and the second structural component 62 are made of LV12 aluminum alloy. The first structural component 61 has a first semi-circular notch and a second semi-circular notch axially formed on one side. The second structural component 62 has a corresponding first semi-circular notch and a second semi-circular notch axially formed on one side. The two first semi-circular notches connect to form a first through hole that matches the outer diameter of the rotating rod 4. The two second semi-circular notches connect to form a second through hole that matches the outer diameter of the bushing 53 of the dial indicator 5. Radial through holes are formed at both ends of the first structural component 61. Radial threaded holes are formed on the second structural component 62 at the corresponding positions of the radial through holes. One end of the rotating rod 4 passes through the first through hole, and the bushing 53 of the dial indicator 5 passes through the second through hole. Two dial indicator fixing screws 7 sequentially pass through the radial through holes of the first structural component 61 and are threaded into the radial threaded holes of the second structural component 62.

[0072] The entire assembly consisting of the rotating rod sleeve 3, the rotating rod 4, the dial indicator 5, and the fixing structure 6 can rotate around the target seat 2. It is worth noting that each centering target seat mechanism is equipped with two rotating rod sleeves 3, one in front and one behind, which facilitates the installation of the dial indicator 5 on both sides and improves the versatility of the centering target seat mechanism.

[0073] Based on the aforementioned target mounting mechanism, this invention also provides a rapid measurement and adjustment method for the central axis of the sensing cavity bore, the adjustment principle of which is based on the measurement technology of a laser tracker. For example... Figure 8 , Figure 9 As shown, the laser tracker 16 is a precision three-dimensional coordinate measuring instrument, mainly including an angle measurement module, a distance measurement module, a tracking control module, a laser tracker target 17, a tripod, and a data processing terminal. It is widely used in precision installation of large equipment, machining and manufacturing, aerospace, and other fields. The accompanying SA software is used for instrument operation and data post-processing. The laser tracker target 17, also known as a target sphere, is a spherical object with a triangular reflector, used in conjunction with the laser tracker 16 to measure the coordinates of the center of the tracker target 17; it is a precision optical device. The support adjustment module 19 is a mechanical load-bearing module capable of adjusting up and down, forward and backward, and left and right. Its upper end is fixed to the sensing cavity 18 under test by bolts. Each sensing cavity 18 uses four support adjustment modules 19 in conjunction to adjust the six degrees of freedom of the sensing cavity 18: up and down, forward and backward, left and right, lateral tilt, side tilt, and pitch, thereby adjusting the central axis of the sensing cavity.

[0074] The rapid measurement and adjustment method for the central axis of the sensing cavity bore of the present invention specifically includes the following steps:

[0075] Step 1: Establish a control network. Use a laser tracker 16 to measure the coordinates of the network points, and then backfit the measured coordinates to obtain the device coordinate system 20 where the sensing cavity 18 is located. Specifically, the control network is a technical term in laser tracker measurement technology, referring to a network of multiple fixed measurement points set around the device. By measuring a portion of these coordinate sets at any spatial location, the laser tracker 16 can accurately backfit the device coordinate system 20, eliminating the need to repeatedly measure a large number of points, lines, and surface features of the device itself, thus significantly improving measurement efficiency.

[0076] Based on the relative position of the theoretical position of the sensing cavity 18 under test and the coordinate system 20 of the device, the coordinate representation of the theoretical central axis of the sensing cavity 18 under test in the coordinate system 20 of the device is obtained. For ease of discussion and understanding, this specification assumes that the theoretical central axis of the sensing cavity 18 under test coincides with the X-axis of the coordinate system 20 of the device, that is, the Y and Z coordinates of each point on the theoretical central axis of the sensing cavity 18 under test are both 0. Furthermore, since the axial dimension installation accuracy requirement is low, it is not necessary to adjust the X-axis coordinate when adjusting the position of the central axis, and it is considered that the slight change in the X-axis coordinate caused by the adjustment process of the central axis is acceptable.

[0077] Step 2: Assemble two sets of the above-mentioned centering target base mechanisms 21. The rotating rod 4 of one set of centering target base mechanisms 21 is mounted on the rotating rod sleeve 3 on the front side of the mounting flange 202, and the rotating rod 4 of the other set of centering target base mechanisms 21 is mounted on the rotating rod sleeve 3 on the rear side of the mounting flange 202. The two sets of centering target base mechanisms 21 are vertically mounted on the front and rear end faces of the sensing cavity 18 to be measured, respectively, so that the two frames 1 are threadedly connected to the front or rear insertion parts in the inner hole, and the dial indicators 5 of both sets of centering target base mechanisms 21 face the direction of the inner hole of the sensing cavity 18 to be measured, i.e., the two dial indicators 5 are set opposite each other.

[0078] Step 3: Adjust the relative positions of the two dial indicators 5 and the corresponding rotating rods 4 so that the measuring heads 54 of the two dial indicators 5 are in contact with the front and rear insertion parts in the inner hole of the sensing cavity 18 at the center of their stroke. Then tighten the fixing screws 63.

[0079] Step 4: Calibrate the dial indicators 5 of the two sets of centering target base mechanisms 21. Specifically, slightly loosen the locking screws 8 of the two sets of centering target base mechanisms 21, and then adjust the corresponding fine adjustment screws 12 respectively, so that when the dial indicator 5 rotates one revolution along the target base 2, the displacement scale indicated on the dial indicator 5 changes by no more than 0.1mm (10 small divisions). At this time, tighten the locking screws 8 and the fine adjustment locking nuts 13.

[0080] Step 5: The laser tracker target 17 is successively attached to the target seat 2 of the two sets of centering target seat mechanisms 21. Then, the laser tracker 16 measures the coordinates (X1, Y1, Z1) and (X2, Y2, Z2) of the two center points of the front and rear end faces of the sensing cavity 18 under the device coordinate system 20. Their theoretical coordinates should be equal to (X1', 0, 0) and (X2', 0, 0) respectively, where X1≈X1' and X2≈X2'.

[0081] Step 6: Connect the coordinates of the two center points of the front and rear end faces of the sensing cavity 18 under the device coordinate system 20 and record it as the measured central axis of the sensing cavity 18. According to the offset of the measured central axis of the sensing cavity 18 relative to the theoretical central axis of the sensing cavity 18, adjust the four support adjustment modules 19 of the sensing cavity 18 under the device coordinate system 20. At the same time, use the laser tracker 16 to measure cyclically until the Y coordinate and ordinate values ​​Y1, Z1, Y2, Z2 of the two center points of the front and rear end faces of the sensing cavity 18 under the device coordinate system 20 are all less than the design error threshold of 0.1mm. That is, the two center points of the front and rear end faces of the sensing cavity 18 under the device coincide with the X-axis with an error of less than 0.1mm, and the measurement of the central axis of the sensing cavity 18 under the device is completed.

[0082] In this embodiment, the measurement of the central axis of the inner hole of the sensing cavity is achieved by a target base mechanism. At this time, the measuring head of dial indicator 5 is installed radially outward, that is, the measuring head is in contact with the inner hole surface. This target base mechanism can also be used to measure the central axis of the outer circle of other equipment. In this case, the dial indicator must be rotated 180° so that the measuring head is installed radially inward, that is, the measuring head is in contact with the outer circle surface. The measurement method is similar to the method for measuring the central axis of the inner hole of the sensing cavity.

Claims

1. A centering target holder mechanism, characterized in that: It includes a skeleton (1), a target seat (2), at least one rotating rod sleeve (3), a rotating rod (4), a dial indicator (5), four sets of adjustment components, and at least three locking screws (8); The skeleton (1) is a long strip structure with connecting through holes (101) at both ends for connecting to the object to be tested; the skeleton (1) has an installation through hole (102) at its center. The target holder (2) includes a hollow cylinder (201) and a mounting flange (202) disposed on the outer side wall of the hollow cylinder (201); the hollow cylinder (201) passes through the mounting through hole (102) and is clamped to one side of the frame (1) by the mounting flange (202); One end of the hollow cylinder (201) is set as an inner conical surface, and a magnet (14) is provided on the inner side of the inner conical surface to attract the laser tracker target (17) onto the inner conical surface through the magnet (14). The rotating rod sleeve (3) is sleeved on the outer wall of the hollow cylinder (201), and the inner wall of the rotating rod sleeve (3) and the outer wall of the hollow cylinder (201) are in tight clearance fit. One end of the rotating rod (4) is threaded to the outer wall of the rotating rod sleeve (3), and the other end is connected to the dial indicator (5); The adjustment assembly includes fine-tuning side plates (10) and fine-tuning screws (12); four fine-tuning side plates (10) are symmetrically fixed on the frame (1) in pairs, and the four fine-tuning side plates (10) are all arranged opposite to the outer wall of the mounting flange (202); the fine-tuning side plates (10) are provided with threaded holes at the positions corresponding to the outer wall of the mounting flange (202), and the four fine-tuning screws (12) pass through the threaded holes on the corresponding fine-tuning side plates (10) and abut against the outer wall of the mounting flange (202); The frame (1) is provided with at least three through holes (103) in the circumferential direction corresponding to the mounting flange (202). The diameter of the through holes (103) is larger than the diameter of the locking screws (8). Multiple locking screws (8) pass through the corresponding through holes (103) of the frame (1) and are threaded to the mounting flange (202) for fine-tuning and locking the target seat (2).

2. The centering target holder mechanism according to claim 1, characterized in that: The adjustment assembly also includes four fine-tuning locking nuts (13); The four fine-tuning locking nuts (13) are used to be installed on the corresponding fine-tuning set screws (12) and tightened after the fine-tuning set screws (12) have been adjusted.

3. The centering target holder mechanism according to claim 2, characterized in that: The four fine-tuning side plates (10) are symmetrically fixed in pairs in the length and width directions of the skeleton (1). The two fine-tuning side plates (10) fixed in the length direction of the skeleton (1) are respectively installed on the surface of the skeleton (1) by two fixing screws (11), and the two fine-tuning side plates (10) fixed in the width direction of the skeleton (1) are respectively installed on the two side walls of the skeleton (1) by two fixing screws (11). The skeleton (1) has two fine-tuning set screws (12) on the corresponding length direction with strip-shaped through holes (104) along the length direction.

4. A centering target holder mechanism according to any one of claims 1-3, characterized in that: The number of rotating rod sleeves (3) is two; The two rotating rod sleeves (3) are respectively sleeved on the outer walls of the hollow cylinder (201) on both sides of the mounting flange (202); One end of the rotating rod (4) is threaded to the outer wall of any rotating rod sleeve (3); The magnet (14) is detachably mounted on the inner conical surface of the hollow cylinder (201).

5. A centering target holder mechanism according to claim 4, characterized in that: It also includes a fixed structure (6); The fixing structure (6) includes a first structural member (61), a second structural member (62), and two dial indicator fixing screws (7); The first structural member (61) has a first semi-circular notch and a second semi-circular notch axially opened on one side, and the second structural member (62) has a first semi-circular notch and a second semi-circular notch axially opened on the corresponding position on one side. The two first semi-circular notches are connected to form a first through hole that matches the outer diameter of the rotating rod (4), and the two second semi-circular notches are connected to form a second through hole that matches the outer diameter of the bushing of the dial indicator (5). The first structural member (61) has radial through holes at both ends, and the second structural member (62) has radial threaded holes at the corresponding positions of the radial through holes; One end of the rotating rod (4) passes through the first through hole, the bushing (53) of the dial indicator (5) passes through the second through hole, and the two dial indicator fixing screws (7) pass through the radial through hole of the first structural member (61) and are threadedly connected to the radial thread hole of the second structural member (62).

6. The centering target holder mechanism according to claim 5, characterized in that: It also includes two retaining rings (15); The hollow cylinder (201) has retaining ring grooves (203) at both ends of its outer side wall, which are close to the outer sides of the two rotating rod sleeves (3); The two snap rings (15) are installed in the corresponding snap ring grooves (203), and their inner end faces abut against the outer end faces of the corresponding rotating rod sleeves (3).

7. A centering target holder mechanism according to claim 6, characterized in that: The skeleton (1) is provided with reinforcing ribs on both sides; The positions of the four fine-tuning screws (12) on the outer side wall of the mounting flange (202) are set as planes.

8. The centering target holder mechanism according to claim 1, characterized in that: The frame (1) and the rotating rod (4) are both made of LY12 aluminum alloy. The target holder (2), rotating rod sleeve (3), and fine-tuning side plate (10) are all made of 304 stainless steel.

9. A method for rapid measurement and adjustment of the central axis of an induction cavity bore, employing the centering target base mechanism as described in any one of claims 1-8, characterized in that, Includes the following steps: Step 1: Establish a control network. Use a laser tracker (16) to measure the coordinates of the network points of the control network, and obtain the device coordinate system (20) where the sensing cavity (18) is located by backfitting based on the measured network point coordinates. The control network is a network composed of multiple fixed measurement points set around the sensing cavity (18). Step 2: Assemble two sets of centering target base mechanisms (21) as described in any one of claims 1-8. The rotating rod (4) of one set of centering target base mechanisms (21) is installed on the rotating rod sleeve (3) on the front side of the mounting flange (202), and the rotating rod (4) of the other set of centering target base mechanisms (21) is installed on the rotating rod sleeve (3) on the rear side of the mounting flange (202). The two sets of centering target base mechanisms (21) are respectively vertically installed on the front and rear insertion parts of the sensing cavity (18) to be tested, and the dial indicators (5) of the two sets of centering target base mechanisms (21) are both facing the direction of the inner hole of the sensing cavity (18) to be tested. Step 3: Adjust the relative positions of the two dial indicators (5) and the corresponding rotating rod (4) until the measuring heads of the two dial indicators (5) are in contact with the front and rear plug-in parts in the inner hole of the sensing cavity (18) to be measured at the center of their stroke. Step 4: Calibrate the dial gauges (5) of the two sets of centering target base mechanisms (21); Step 5: The laser tracker target (17) is attached to the two target seats (2) one after the other, and the coordinates of the two center points of the front and rear end faces of the sensing cavity (18) under the device coordinate system (20) are measured by the laser tracker (16). Step 6: Connect the coordinates of the two center points of the front and rear end faces of the sensing cavity (18) under the device coordinate system (20) and record it as the measured central axis of the sensing cavity (18). According to the offset of the measured central axis of the sensing cavity (18) relative to its theoretical central axis, adjust the four support adjustment modules (19) of the sensing cavity (18) and use the laser tracker (16) to measure cyclically until the measured central axis of the sensing cavity (18) coincides with its theoretical central axis, and complete the measurement of the central axis of the sensing cavity (18).

10. A method for rapid measurement and adjustment of the central axis of an induction cavity bore according to claim 9, characterized in that, Step 4 is as follows: Loosen the locking screws (8) of the two sets of centering target base mechanisms (21), and then adjust the corresponding fine adjustment set screws (12) so that when the dial indicator (5) rotates one revolution along the target base (2), the change in the displacement scale indicated on the dial of the dial indicator (5) does not exceed the set threshold. At this time, tighten the locking screws (8) and the fine adjustment locking nut (13) to complete the calibration of the dial indicator (5).

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