Centering target seat mechanism and rapid measuring and adjusting method for central axis of inner hole of induction cavity

Abstract

The invention provides a centering target seat mechanism and a rapid measuring and adjusting method for the central axis of an inner hole of an induction cavity. The method is used for solving the technical problems that hardware supporting facilities are complex, the operation process is tedious and the working efficiency is low in an existing method for measuring the central axis of the inner hole of the induction cavity based on a laser, a centering device, a photosensitive diode and a reflecting plane mirror. On the basis of the laser tracker measurement technology, the centering target seat mechanism with the dial indicator, the rotating rod, the fine adjustment jackscrew and other components is designed, and the centering target seat mechanism places the target seat at the center point of the inner hole of the induction cavity to be measured with high precision. A laser tracker is adopted to measure the center point coordinates of the part at the inserting position of the induction cavity; through the two sets of same centering target seat mechanisms, the center point coordinates of the front end face and the rear end face of the induction cavity can be measured at the same time, and therefore the central axis of the inner hole of the induction cavity can be rapidly measured.

Description

Technical Field

[0001] The invention relates to the measurement of the central axis of a hole in an induction cavity, and in particular to a target centering seat mechanism and a method for quickly measuring and adjusting the central axis of a hole in an induction cavity. Background Art

[0002] At present, large-scale pulse power devices using induced voltage superposition (IVA) technology have multi-stage series induction cavities, which are complex pancake-shaped assembly structures with inner holes. The induction cavity is fixed on a supporting beam equipped with a guide rail. During assembly, the two adjacent induction cavities need to be centrally plugged in with the central axis horizontal, and the plug-in is a coaxial structure with clearance fit. In order to ensure the performance of the device, the central axis of each stage of the induction cavity should coincide with the theoretical central axis when assembled in series. Therefore, in the assembly process of the multi-stage series induction cavity, not only the coaxial accuracy of the plug-in of the two adjacent induction cavities must be ensured, but also the central axis of the inner hole of the induction cavity must be accurately measured and adjusted to ensure the alignment accuracy of the overall central axis relative to the theoretical central axis after the multi-stage induction cavity is assembled in series, thereby controlling the cumulative error.

[0003] Considering the large size and multiple stages of the induction cavity, the workload of measurement and adjustment is large. It is of great significance to achieve "fast measurement" on the basis of "accurate measurement" to improve the efficiency of device construction and implementation. The existing induction cavity inner hole centerline measurement method based on "laser + centering device + photosensitive diode + reflective plane mirror" has complex hardware supporting facilities, cumbersome operation process, low work efficiency, and is not conducive to practical application. In addition, no literature reports have been found on the use of other devices and methods to efficiently measure and adjust the centerline of multi-stage induction cavities in series. Summary of the invention

[0004] The purpose of the present invention is to solve the technical problems of complex hardware supporting facilities, cumbersome operation process and low work efficiency in the existing method for measuring the centerline of the hole in the sensing cavity based on "laser + centering device + photosensitive diode + reflective plane mirror", and to provide a method for quickly measuring and adjusting the centerline of the target seat mechanism and the centerline of the hole in the sensing cavity.

[0005] The inventive concept of the present invention is: based on the laser tracker measurement technology, a centering target seat mechanism including a dial indicator, a rotating rod, a fine-tuning screw and other components is designed, which can place the target seat at the center point of the inner hole of the sensing cavity to be measured with high accuracy, so that the center point coordinates of the parts at the insertion of the sensing cavity can be measured by the laser tracker. By using two sets of the same centering target seat mechanism, the center point coordinates of the front and rear end faces of the sensing cavity can be measured simultaneously, thereby realizing the rapid measurement and adjustment of the center axis of the inner hole of the sensing cavity.

[0006] In order to achieve the above purpose and complete the above invention concept, the technical solution proposed by the present invention is:

[0007] A target seat centering mechanism, which is special in that it includes a frame, a target seat, 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 skeleton is a long strip structure, with connecting through holes at both ends for connecting with the object to be tested, such as the sensing cavity; a mounting through hole is opened at the center of the skeleton;

[0009] The target seat comprises a hollow cylinder and a mounting flange arranged on the outer side wall of the hollow cylinder; the hollow cylinder passes through the mounting through hole and is clamped on one side of the frame through the mounting flange;

[0010] One end of the hollow cylinder is configured as an inner conical surface, and a magnetic steel is disposed on the inner side of the inner conical surface, so as to adsorb the target of the laser tracker onto the inner conical surface through the magnetic steel;

[0011] The rotating rod sleeve is sleeved on the outer wall of the hollow cylinder, and the inner wall of the rotating rod sleeve and the outer wall of the hollow cylinder are closely matched with each other, so that the rotating rod sleeve can rotate relative to the hollow cylinder;

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

[0013] The adjustment assembly includes a fine-tuning side plate and a fine-tuning top screw; the four fine-tuning side plates are symmetrically fixed to the frame in pairs, and the four fine-tuning side plates are arranged opposite to the outer side wall of the mounting flange; the fine-tuning side plates are provided with threaded holes at positions corresponding to the outer side wall of the mounting flange, and the four fine-tuning top screws respectively pass through the threaded holes on the corresponding fine-tuning side plates and abut against the outer side wall of the mounting flange;

[0014] At least three through holes are arranged circumferentially at positions corresponding to the mounting flanges on the skeleton, and the aperture of the through holes is larger than the diameter of the locking screws; a plurality of locking screws respectively pass through the corresponding through holes of the skeleton and are threadedly connected to the mounting flanges for locking the target seat after fine adjustment.

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

[0016] The four fine-tuning locking nuts are used to be installed on the corresponding fine-tuning top screws and are tightened after the fine-tuning top screws are adjusted.

[0017] Furthermore, the four fine-tuning side panels are symmetrically fixed in pairs in the length direction and width direction of the frame, the two fine-tuning side panels fixed in the length direction of the frame are respectively installed on the surface of the frame by two fixing screws, and the two fine-tuning side panels fixed in the width direction of the frame are respectively installed on the side walls of the frame by two fixing screws;

[0018] The positions of the two fine-tuning top screws corresponding to the length direction on the frame are provided with strip-shaped through holes along the length direction.

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

[0020] The two rotating rod sleeves are respectively sleeved on the outer side walls of the hollow cylinder on both sides of the mounting flange;

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

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

[0023] Further, it also includes a fixing structure;

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

[0025] A first semicircular notch and a second semicircular notch are axially opened on one side of the first structural member, and a first semicircular notch and a second semicircular notch are axially opened on a corresponding position on one side of the second structural member, the two first semicircular notches are connected to form a first through hole adapted to the outer diameter of the rotating rod, and the two second semicircular notches are connected to form a second through hole adapted to the outer diameter of the shaft sleeve of the dial indicator;

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

[0027] One end of the rotating rod passes through the first through hole, the shaft sleeve of the dial indicator passes through the second through hole, and the two dial indicator fixing screws respectively pass through the radial through holes of the first structural member in sequence and are threadedly connected with the radial threaded holes of the second structural member.

[0028] Further, two clip springs are included;

[0029] The outer wall of the hollow cylinder is provided with retaining spring grooves at two ends adjacent to the outer sides of the two rotating rod sleeves;

[0030] The two clamping springs are installed in corresponding clamping spring grooves, and the inner end surfaces thereof abut against the outer end surfaces of the corresponding rotating rod sleeves.

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

[0032] The positions corresponding to the four fine-tuning screws on the outer side wall of the mounting flange are arranged as planes.

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

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

[0035] At the same time, the present invention also provides a method for quickly measuring and adjusting the central axis of the inner hole of the sensing cavity, which adopts the above-mentioned centering target seat 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 grid point coordinates of the control network, and reversely fit the measured grid 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 grid points arranged around the sensing cavity;

[0037] Step 2, assemble two sets of the above-mentioned centering target seat mechanisms, wherein the rotating rod of one set of the centering target seat 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 the centering target seat mechanisms is installed on the rotating rod sleeve on the rear side of the mounting flange; the two sets of the centering target seat mechanisms are respectively vertically installed on the front plug-in parts and the rear plug-in parts of the sensing cavity to be tested, and the dial indicators of the two sets of the centering target seat mechanisms are both facing the direction of the inner hole of the sensing cavity to be tested;

[0038] Step 3, respectively adjusting 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 plug-in parts and the rear plug-in parts in the inner hole of the sensing cavity to be measured at the stroke center;

[0039] Step 4, calibrating the two sets of dial indicators of the target seat centering mechanism;

[0040] Step 5, adsorbing the laser tracker target on two target seats respectively, and then measuring the coordinates of the two center points of the front and rear end surfaces of the sensing cavity to be measured in the device coordinate system respectively by the laser tracker;

[0041] Step 6, record the coordinate point connection line of the two center points of the front and rear end surfaces of the sensing cavity to be measured in the device coordinate system as the measured central axis of the sensing cavity to be measured, and adjust the four support adjustment modules of the sensing cavity to be measured according to the offset of the measured central axis of the sensing cavity to be measured relative to its theoretical central axis. At the same time, use a laser tracker to perform cyclic measurement until the measured central axis of the sensing cavity to be measured coincides with its theoretical central axis, thereby completing the measurement of the central axis of the sensing cavity to be measured.

[0042] Furthermore, step 4 is specifically as follows:

[0043] Loosen the locking screws of the two sets of target seat alignment mechanisms, and then adjust the corresponding fine-tuning screws respectively so that when the dial indicator rotates one circle along the target seat, the displacement scale indicated on the dial of the dial indicator does not change by more than the set threshold. At this time, tighten the locking screws and fine-tuning locking nuts to complete the calibration of the dial indicator.

[0044] Compared with the prior art, the present invention has the following beneficial effects:

[0045] 1. A centering target seat mechanism provided by the present invention skillfully combines a mechanical centering mechanism with a laser tracker measurement technology, and can quickly and effectively install the centering target seat mechanism on the central axis of the inner hole of the sensing cavity to be measured; at the same time, the target seat is set as a hollow structure. When measuring the center point of the other end of the sensing cavity, the hollow structure can provide an optical path channel for the laser tracker, and two sets of centering target seat mechanisms can be installed on the front and rear end surfaces of the sensing cavity at the same time to implement measurement, which effectively improves the measurement efficiency; the centering target seat mechanism of the present invention has a simple composition, high measurement accuracy and efficiency, and can be widely used in other similar demand occasions.

[0046] 2. The target centering seat mechanism provided by the present invention can be equipped with dial indicators on both the front and rear sides. The same set of mechanisms can be used to measure the center point of the other end of the sensing cavity by simple switching, thereby improving the versatility and standardization of the target centering seat mechanism.

[0047] 3. The target centering seat mechanism provided by the present invention can measure the outer circle or inner hole of a part respectively by changing the inner and outer directions 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 method for quickly measuring and adjusting the center axis of the inner hole of the sensing cavity. It only needs to measure the coordinates of the two center points of the front and rear end surfaces of the inner hole of the sensing cavity to be measured. Compared with the traditional laser tracker-based measurement method, which requires measuring multiple points on the cylindrical surface of the inner hole and performing fitting calculations on the software, the measurement method of the present invention is more direct and efficient.

[0049] 5. The present invention provides a method for rapid measurement and adjustment of the central axis of the hole in the sensing cavity. In terms of hardware, it only requires a target seat mechanism and a laser tracker, and does not require complex hardware such as lasers, target centering devices, photodiodes, reflectors and other similar devices for measurement methods. The system composition and operation process are simpler. BRIEF DESCRIPTION OF THE DRAWINGS

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

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

[0052] Figure 3 It is a schematic diagram of the partial structure of the skeleton in an embodiment of the centering target seat mechanism of the present invention;

[0053] Figure 4 It is a structural schematic diagram of a target seat in an embodiment of a target seat centering mechanism of the present invention;

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

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

[0056] Figure 7 It is a structural schematic diagram of a rotating rod, a fixing structure and a dial indicator in an embodiment of a target seat centering mechanism of the present invention;

[0057] Figure 8 It is a schematic diagram of the principle of an embodiment of a method for rapid measurement and adjustment of the central axis of a hole in a sensing cavity of the present invention;

[0058] Fig. 9 for Figure 8 A partial enlarged view of .

[0059] The specific reference numerals are as follows:

[0060] 1-skeleton, 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-circlip groove; 3-rotating rod sleeve; 4-rotating rod; 5-dial indicator, 51-dial, 52-needle, 53-sleeve, 54-measuring head; 6-fixing structure, 61-first structural member, 62-second structural member; 7-dial indicator fixing screw; 8-locking screw; 9-locking gasket; 10-fine-tuning side plate; 11-fixing screw; 12-fine-tuning top screw; 13-fine-tuning locking nut; 14-magnetic steel; 15-circlip; 16-laser tracker; 17-laser tracker target; 18-sensing chamber to be measured; 19-support adjustment module; 20-device coordinate system; 21-centering target seat mechanism. DETAILED DESCRIPTION

[0061] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0062] Aiming at the problem of measuring the central axis during the assembly of multi-stage series induction chambers, the present invention proposes a target seat centering mechanism and a method for quickly measuring and adjusting the central axis of the inner hole of the induction chamber based on the mechanism. The induction chamber is a large-sized hollow pancake-shaped complex assembly. In this example, the outer diameter of the induction chamber to be measured is about 3 meters, and the inner hole diameter is about 0.8 meters. The cylindrical surface of the inner hole of the induction chamber is composed of three plug-in parts: front, middle, and rear. The front plug-in part is used to cooperate with the rear plug-in part of the previous stage induction chamber, and the rear plug-in part is used to cooperate with the front plug-in part of the next stage induction chamber. Therefore, it is necessary to determine the central axis of the induction chamber to complete the front and rear plug-in with the front and rear induction chambers.

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

[0064] like Figure 3 As shown, the skeleton 1 is the main frame of the target seat mechanism, which is a long strip structure as a whole, and its length is determined according to the structure to be measured. In order to reduce the weight, the skeleton 1 is made of LY12 aluminum alloy. Threaded holes are provided on the front plug-in parts and the rear plug-in parts in the inner hole of the sensing cavity 18 to be measured, and connecting through holes 101 are respectively provided at both ends of the skeleton 1, which are used to allow screws to pass through the corresponding connecting through holes 101 and connect and fix with the object to be measured, for example, to connect and fix with the threaded holes of the front plug-in parts or the rear plug-in parts of the sensing cavity 18 to be measured. At the same time, a mounting through hole 102 is provided at the center of the skeleton 1 for mounting and fixing the target seat 2.

[0065] like Figure 4 As shown, the target seat 2 is the core component of the target seat centering mechanism, which includes a hollow cylinder 201 and a mounting flange 202 arranged on the outer wall of the hollow cylinder 201. The hollow cylinder 201 and the mounting flange 202 are integrated structures, both made of 304 stainless steel. The hollow cylinder 201 passes through the mounting through hole 102 of the skeleton 1, and is clamped on one side of the skeleton 1 through the mounting flange 202 on the outer wall of the hollow cylinder 201. Four through holes 103 are circumferentially arranged at the positions corresponding to the mounting flange 202 on the skeleton 1, and four threaded blind holes are opened at the positions corresponding to the four through holes 103 on the mounting flange 202, wherein the aperture of the through hole 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 are respectively passed through the locking gasket 9 and two through holes 103 at any diagonal position of the frame 1 and are threadedly connected with the corresponding threaded holes on the mounting flange 202, and the remaining two locking screws 8 are respectively passed through the remaining two through holes 103 of the frame 1 and are threadedly connected with the corresponding threaded holes on the mounting flange 202, so as to realize the connection and fixation between the target seat 2 and the frame 1 after fine adjustment. The locking gasket 9 is a strip-shaped part with holes, made of 304 stainless steel.

[0066] like Figure 5 As shown, each set of adjustment components includes a fine-tuning side plate 10, two fixing screws 11, a fine-tuning top screw 12 and a fine-tuning locking nut 13. The four fine-tuning side plates 10 are symmetrically fixed in pairs in the length direction and width direction of the skeleton 1. Specifically, the fine-tuning side plates 10 are rectangular structures with through holes and threaded holes. They are made of 304 stainless steel. 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 through 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 side walls of the skeleton 1 through two fixing screws 11. At the same time, the four fine-tuning side plates 10 are all arranged opposite to the outer side wall of the mounting flange 202, and the four fine-tuning top screws 12 respectively pass through the threaded holes on the corresponding fine-tuning side plates 10 and abut against the outer side wall of the mounting flange 202 to achieve the plane position adjustment of the target seat 2. Preferably, the fine-tuning screw 12 is a standard knurled flat head screw, which is convenient for manual adjustment to improve the efficiency of the adjustment operation. Accordingly, the positions corresponding to the four fine-tuning screws 12 on the outer wall of the mounting flange 202 are set to be flat to improve the adjustment accuracy. Four fine-tuning locking nuts 13 are used to be installed on the corresponding fine-tuning screws 12, and they are tightened after the fine-tuning screws 12 are adjusted.

[0067] In addition, in this embodiment, the positions of the two fine-tuning screws 12 in the longitudinal direction of the frame 1 are provided with strip-shaped through holes 104, which are convenient for adjusting the fine-tuning screws 12 with fingers, and conform to the ergonomic design. Reinforcement ribs are also designed on both sides of the frame 1 to increase rigidity and reduce deformation.

[0068] One end of the hollow cylinder 201 of the target seat 2 is set as an inner conical surface, which serves as the adsorption and matching surface of the laser tracker target 17. A detachable magnetic steel 14 is set on the inner side of the inner conical surface. The magnetic steel 14 is a disc-shaped metal with strong magnetism, which is used to firmly adsorb the laser tracker target 17 on the inner conical surface by relying on its strong magnetism. Among them, the internal space of the hollow cylinder 201 is used to provide an optical path channel for the laser tracker, so that it can measure the laser tracker target 17 on the other side without disassembling the target seat mechanism on this side, and only remove the magnetic steel 14, thereby effectively improving the measurement efficiency. Specifically, when it is necessary to measure the center point of the other side of the induction cavity 18 to be measured, the magnetic steel 14 on the current side can be removed to restore the laser path of the inner hole of the target seat 18 to be measured.

[0069] like Figure 6As shown, the rotating rod sleeve 3 is a cylindrical structure as a whole, made of 304 stainless steel, and the two rotating rod sleeves 3 are respectively sleeved on the outer wall of the hollow cylinder 201 on both sides of the mounting flange 202, and the inner wall of the rotating rod sleeve 3 and the outer wall of the hollow cylinder 201 are closely matched to realize the circumferential rotation of the rotating rod sleeve 3 relative to the hollow cylinder 201. The outer wall of the hollow cylinder 201 of the target seat 2 is adjacent to the outer sides of the two rotating rod sleeves 3 at both ends, and the retaining spring grooves 203 are respectively provided. The retaining spring 15 is a standard part. The two retaining springs 15 are installed in the corresponding retaining spring grooves 203, and the inner end faces are against the outer end faces of the corresponding rotating rod sleeves 3 to prevent the rotating rod sleeve 3 from axial movement and slipping.

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

[0071] like Figure 7 As shown, the dial gauge 5 is a standard measuring tool product, which includes a dial 51, a needle 52 arranged on the dial 51, a sleeve 53 installed on the side of the dial 51, and a measuring head 54 connected to the inside of the needle 52 and coaxially passing through the sleeve 53. When the measuring head 54 is telescopically displaced, the scale of the needle 52 will change accordingly. When the measuring head 54 is displaced by 1mm, the measuring accuracy is 0.01mm for each rotation of the needle 52. The measuring range of this embodiment is 10mm. The fixing structure 6 includes a first structural member 61, a second structural member 62, and two dial gauge fixing screws 7. The first structural member 61 and the second structural member 62 are both made of LV12 aluminum alloy. A first semicircular notch and a second semicircular notch are axially formed on one side of the first structural member 61, and a first semicircular notch and a second semicircular notch are axially formed on a corresponding position on one side of the second structural member 62. The two first semicircular notches are connected to form a first through hole that matches the outer diameter of the rotating rod 4, and the two second semicircular notches are connected to form a second through hole that matches the outer diameter of the shaft sleeve 53 of the dial gauge 5. Both ends of the first structural member 61 are respectively provided with radial through holes, and the second structural member 62 is provided with radial threaded holes at positions corresponding to the radial through holes. One end of the rotating rod 4 passes through the first through hole, and the shaft sleeve 53 of the dial gauge 5 passes through the second through hole. Two dial gauge fixing screws 7 are respectively passed through the radial through holes of the first structural member 61 and are threadedly connected with the radial threaded holes of the second structural member 62.

[0072] The whole composed of the rotating rod sleeve 3, the rotating rod 4, the dial indicator 5 and the fixed structure 6 can rotate around the target seat 2. It is particularly pointed out that two front and rear rotating rod sleeves 3 are installed on each set of the target seat centering mechanism, which is convenient for the installation of the dial indicator 5 on both sides, thereby improving the versatility of the target seat centering mechanism.

[0073] Based on the above-mentioned target seat centering mechanism, the present invention also provides a method for quickly measuring and adjusting the central axis of the hole in the induction cavity, and the adjustment principle is based on the measurement technology of the laser tracker. Figure 8 , Fig. 9 As shown, the laser tracker 16 is a spatial three-dimensional coordinate precision measuring instrument, which mainly includes an angle measurement module, a distance measurement module, a tracking control module, a laser tracker target 17, a tripod and a data processing terminal, etc. It is widely used in the fields of precision installation of large equipment, mechanical processing and manufacturing, aerospace, etc. The supporting SA software is used for instrument control and data post-processing. The laser tracker target 17, also known as the target ball, is a spherical body with a triangular prism reflector, which is used in conjunction with the laser tracker 16 and can measure the coordinates at the center of the tracker target 17. It is a precision optical device. The support adjustment module 19 is a mechanical bearing module that can achieve three degrees of freedom adjustment: up and down, front and back, and left and right. Its upper end face is fixed to the sensing cavity 18 to be tested by bolts. Each sensing cavity 18 to be tested uses four support adjustment modules 19 to cooperate with each other to adjust the six degrees of freedom of the sensing cavity 18 to be tested, namely, up and down, front and back, left and right, yaw angle, roll angle, and pitch angle, thereby adjusting the central axis of the sensing cavity.

[0074] The method for quickly measuring and adjusting the central axis of the inner hole of the induction cavity of the present invention specifically comprises the following steps:

[0075] Step 1, establish a control network, use a laser tracker 16 to measure the grid point coordinates of the control network, and reversely fit the measured grid point coordinates to obtain the device coordinate system 20 where the sensing cavity 18 to be measured is located. Specifically, the control network is a professional term in laser tracker measurement technology, which refers to a network composed of multiple fixed measurement grid points set around the device. The laser tracker 16 measures a part of these coordinate sets at any spatial position, and can accurately reverse fit the device coordinate system 20, without having to repeatedly measure a large number of point, line, and surface features of the device itself each time, which greatly improves the measurement efficiency.

[0076] According to the relative position relationship between the theoretical position of the sensing cavity 18 to be tested and the device coordinate system 20, the coordinate representation of the theoretical central axis of the sensing cavity 18 to be tested in the device coordinate system 20 is obtained. For the convenience of discussion and understanding, in this specification, the theoretical central axis of the sensing cavity 18 to be tested is made to coincide with the X-axis of the device coordinate system 20, that is, the Y coordinate and Z coordinate of each point on the theoretical central axis of the sensing cavity 18 to be tested are both 0, and because the axial dimension installation accuracy requirement is relatively low, when adjusting the central axis position, it is not necessary to adjust the X-axis coordinate, and it is considered that the slight change in the X-axis coordinate caused by the central axis adjustment process is acceptable.

[0077] Step 2, assemble two sets of the above-mentioned centering target seat mechanism 21, wherein the rotating rod 4 of one set of the centering target seat mechanism 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 the centering target seat mechanism 21 is installed on the rotating rod sleeve 3 on the rear side of the mounting flange 202. The two sets of centering target seat mechanisms 21 are respectively vertically installed on the front and rear end surfaces of the sensing cavity 18 to be tested, so that the two skeletons 1 are respectively threadedly connected with the front plug-in parts or the rear plug-in parts in the inner hole, and the dial indicators 5 of the two sets of centering target seat mechanisms 21 are both facing the direction of the inner hole of the sensing cavity 18 to be tested, that is, the two dial indicators 5 are arranged opposite to each other.

[0078] Step 3, respectively 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 plug-in parts and the rear plug-in parts in the inner hole of the sensing cavity 18 to be measured at the stroke center, and tighten the fixing screws 63 at this time.

[0079] Step 4, calibrate the dial indicators 5 of the two sets of target seat centering mechanisms 21. Specifically, slightly loosen the locking screws 8 of the two sets of target seat centering mechanisms 21, and then adjust the corresponding fine-tuning top screws 12 respectively, so that when the dial indicator 5 rotates one circle along the target seat 2, the displacement scale indicated on the dial of the dial indicator 5 does not change by more than 0.1mm (10 small grids). At this time, tighten the locking screws 8 and the fine-tuning locking nut 13.

[0080] Step 5, the laser tracker target 17 is adsorbed on the target seat 12 of the two sets of target seat alignment mechanisms 21 respectively, and then the laser tracker 16 is used to measure 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 to be measured in the device coordinate system 20 respectively. The theoretical coordinates should be equal to (X1', 0, 0) and (X2', 0, 0), respectively, where X1≈X1' and X2≈X2'.

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

[0082] In this embodiment, the measurement of the center axis of the inner hole of the sensing cavity is achieved by centering the target seat mechanism. At this time, the measuring head of the dial indicator 5 is installed radially outward, that is, the measuring head is in contact with the inner hole surface. The target seat mechanism can also be used to measure the outer circle center axis of other equipment. At this time, 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 of measuring the center axis of the inner hole of the sensing cavity.

Claims

1. A target centering seat mechanism, characterized in that: It comprises a frame (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) respectively provided at both ends thereof for connecting with the object to be tested; a mounting through hole (102) is provided at the center of the skeleton (1); The target seat (2) comprises a hollow cylinder (201) and a mounting flange (202) arranged on the outer side wall of the hollow cylinder (201); the hollow cylinder (201) passes through the mounting through hole (102) and is clamped on one side of the frame (1) through the mounting flange (202); One end port of the hollow cylinder (201) is arranged as an inner conical surface, and a magnetic steel (14) is arranged on the inner side of the inner conical surface, so as to adsorb the laser tracker target (17) onto the inner conical surface through the magnetic steel (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 closely matched with each other; One end of the rotating rod (4) is threadedly connected to the outer wall of the rotating rod sleeve (3), and the other end is connected to the dial indicator (5); The adjustment assembly comprises a fine-tuning side plate (10) and a fine-tuning top screw (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 arranged opposite to the outer side wall of the mounting flange (202); threaded holes are provided on the fine-tuning side plates (10) at positions corresponding to the outer side wall of the mounting flange (202), and the four fine-tuning top screws (12) respectively pass through the threaded holes on the corresponding fine-tuning side plates (10) and abut against the outer side wall of the mounting flange (202); At least three through holes (103) are provided on the skeleton (1) at positions corresponding to the mounting flange (202) in the circumferential direction, and the aperture of the through hole (103) is larger than the diameter of the locking screw (8); the plurality of locking screws (8) respectively pass through the corresponding through holes (103) of the skeleton (1) and are threadedly connected to the mounting flange (202) for locking the target seat (2) after fine adjustment.

2. A target centering seat 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 top screws (12) and are tightened after the fine-tuning top screws (12) are adjusted.

3. A target centering seat mechanism according to claim 2, characterized in that: The four fine-adjustment side panels (10) are symmetrically fixed in pairs in the length direction and width direction of the frame (1); the two fine-adjustment side panels (10) fixed in the length direction of the frame (1) are respectively mounted on the surface of the frame (1) by two fixing screws (11); and the two fine-adjustment side panels (10) fixed in the width direction of the frame (1) are respectively mounted on the side walls of both sides of the frame (1) by two fixing screws (11); The skeleton (1) is provided with strip-shaped through holes (104) along the length direction at positions corresponding to two fine-tuning top screws (12) in the length direction.

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

5. A target centering seat mechanism according to claim 4, characterized in that: Also includes a fixing structure (6); The fixing structure (6) comprises a first structural member (61), a second structural member (62) and two dial indicator fixing screws (7); A first semicircular notch and a second semicircular notch are axially formed on one side of the first structural member (61), and a first semicircular notch and a second semicircular notch are axially formed on a corresponding position on one side of the second structural member (62), the two first semicircular notches are connected to form a first through hole that matches the outer diameter of the rotating rod (4), and the two second semicircular notches are connected to form a second through hole that matches the outer diameter of the shaft sleeve of the dial indicator (5); The first structural member (61) has radial through holes at both ends thereof, and the second structural member (62) has radial threaded holes at positions corresponding to the radial through holes; One end of the rotating rod (4) passes through the first through hole, the shaft sleeve (53) of the dial gauge (5) passes through the second through hole, and the two dial gauge fixing screws (7) respectively pass through the radial through holes of the first structural member (61) and are threadedly connected with the radial threaded holes of the second structural member (62).

6. A target centering seat mechanism according to claim 5, characterized in that: Also includes two retaining springs (15); The outer side walls of the hollow cylinder (201) are provided with retaining spring grooves (203) at positions adjacent to the outer sides of the two rotating rod sleeves (3) at both ends thereof; The two clamping springs (15) are installed in corresponding clamping spring grooves (203), and the inner end surfaces thereof abut against the outer end surfaces of the corresponding rotating rod sleeves (3).

7. A target centering seat mechanism according to claim 6, characterized in that: Reinforcing ribs are respectively arranged on both sides of the frame (1); The positions corresponding to the four fine-tuning top screws (12) on the outer side wall of the mounting flange (202) are arranged as a plane.

8. The target centering seat 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 seat (2), the rotating rod sleeve (3) and the 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 a hole in a sensing cavity, using the target centering seat mechanism described in any one of claims 1 to 8, characterized in that: The following steps are involved: Step 1, establishing a control network, using a laser tracker (16) to measure the grid point coordinates of the control network, and reverse fitting based on the measured grid point coordinates to obtain a device coordinate system (20) where the sensing cavity (18) is located; the control network is a network composed of a plurality of fixed measurement grid points arranged around the sensing cavity (18); Step 2, assembling two sets of the target centering seat mechanism (21) described in any one of claims 1 to 8, wherein the rotating rod (4) of one set of the target centering seat mechanism (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 the target centering seat mechanism (21) is installed on the rotating rod sleeve (3) on the rear side of the mounting flange (202); the two sets of the target centering seat mechanism (21) are respectively vertically installed on the front plug-in parts and the rear plug-in parts of the sensing cavity (18) to be tested, and the dial indicators (5) of the two sets of the target centering seat mechanism (21) are both facing the direction of the inner hole of the sensing cavity (18) to be tested; Step 3, respectively adjusting the relative positions of the two dial indicators (5) and the corresponding rotating rods (4) until the measuring heads of the two dial indicators (5) are in contact with the front plug-in parts and the rear plug-in parts in the inner hole of the sensing cavity (18) to be measured at the stroke center; Step 4, calibrating the two sets of dial indicators (5) of the target centering seat mechanism (21); Step 5, the laser tracker target (17) is successively adsorbed on the two target seats (2), and the coordinates of the two center points of the front and rear end surfaces of the sensing cavity (18) to be measured in the device coordinate system (20) are respectively measured by the laser tracker (16); Step 6, record the coordinate point connection line of the two center points of the front and rear end surfaces of the sensing cavity (18) to be measured in the device coordinate system (20) as the measured central axis of the sensing cavity (18) to be measured, adjust the four support adjustment modules (19) of the sensing cavity (18) to be measured according to the offset of the measured central axis of the sensing cavity (18) to be measured relative to its theoretical central axis, and use the laser tracker (16) to perform cyclic measurement at the same time until the measured central axis of the sensing cavity (18) to be measured coincides with its theoretical central axis, thereby completing the measurement of the central axis of the sensing cavity (18) to be measured.

10. A method for rapid measurement and adjustment of the central axis of a hole in a sensing cavity according to claim 9, characterized in that: Step 4 is as follows: The locking screws (8) of the two sets of the target seat centering mechanism (21) are loosened, and the corresponding fine-tuning screws (12) are adjusted respectively, so that when the dial indicator (5) rotates one circle along the target seat (2), the displacement scale indicated on the dial of the dial indicator (5) does not change more than the set threshold value. At this time, the locking screws (8) and the fine-tuning locking nuts (13) are tightened to complete the calibration of the dial indicator (5).

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