阅读说明：本技术 一种基于四点称重的航空发动机转子装配测量装置及双目标优化方法 (Four-point weighing-based aeroengine rotor assembly measuring device and double-target optimization method ) 是由 崔继文 陈越 谭久彬 于 2019-09-25 设计创作，主要内容包括：本发明是一种基于四点称重的航空发动机转子装配测量装置及双目标优化方法。基于圆光栅确定转台的角度定位；基于调心调倾装置确保被测转子同心度、平行度与质心坐标的测量与装配在同一基准下进行；基于四测头测量装置,分别提取各级转子径向装配面的同心度误差和轴向装配面的平行度误差；基于四点称重测量装置,分别提取各级转子质心径向坐标；基于转子装配位姿传递模型,以转子装配体的同轴度和质心偏移量为双优化目标,通过遗传寻优,得到各级转子的最优装配角度。本发明可有效解决航空发动机转子装配后同轴度和不平衡量超标的问题,具有转子几何和质量特性一体化测量、一次性装配合格率高、减小发动机振动的特点。(The invention relates to an aeroengine rotor assembly measuring device based on four-point weighing and a dual-target optimization method. Determining the angular positioning of the turntable based on the circular grating; the method comprises the following steps of ensuring that the measurement and the assembly of the concentricity, the parallelism and the mass center coordinate of a measured rotor are carried out under the same reference based on a centering and inclination adjusting device; based on a four-measuring-head measuring device, respectively extracting the concentricity error of the radial assembly surface and the parallelism error of the axial assembly surface of each stage of the rotor; respectively extracting radial coordinates of the mass center of each stage of the rotor based on a four-point weighing measuring device; based on a rotor assembly pose transfer model, the coaxiality and the mass center offset of a rotor assembly body are used as double optimization targets, and the optimal assembly angle of each stage of rotor is obtained through genetic optimization. The invention can effectively solve the problem that the coaxiality and the unbalance amount of the rotor of the aero-engine exceed the standard after the rotor is assembled, and has the characteristics of integrated measurement of the geometric and quality characteristics of the rotor, high one-time assembly qualification rate and reduction of the vibration of the engine.)

1. The utility model provides an aeroengine rotor assembly measuring device based on four point are weighed which characterized by: the device comprises: the device comprises a base (1), an air flotation shafting (2), a weighing sensor (3), an aligning and inclination adjusting workbench (4), a hydraulic chuck (5), a left upright transverse guide rail (6a), a right upright transverse guide rail (6b), a left upright vertical guide rail (7a), a right upright vertical guide rail (7b), a left lower transverse measuring rod (8a), a left upper transverse measuring rod (8b), a right lower transverse measuring rod (8c), a right upper transverse measuring rod (8d), a left lower telescopic inductive sensor (9a), a left upper telescopic inductive sensor (9b), a right lower lever inductive sensor (9c), a right upper lever inductive sensor (9d) and a measured rotor (10), wherein the air flotation shafting (2) is installed on the central point of the base (1);

the air-floating shaft system (2) comprises an air-floating upper plate (2a), an air-floating main shaft (2b), an air-floating lower plate (2c), a circular grating ruler (2d), a circular grating reading head (2e), a motor stator (2f) and an electronic rotor (2 g); the air-floatation upper plate (2a) is installed at the upper end of an air-floatation main shaft (2b), the air-floatation lower plate (2c) is installed at the lower end of the air-floatation main shaft (2b), the circular grating ruler (2d) is installed on the outer wall of the side face of the air-floatation lower plate (2a), the circular grating reading head (2e) is installed on the inner wall of the base (1), and the circular grating reading head (2e) is transversely aligned with the circular grating ruler (2 d);

the weighing sensor (3) comprises a weighing sensor (3a), a weighing sensor (3b), a weighing sensor (3c) and a weighing sensor (3d), and the weighing sensor (3a), the weighing sensor (3b), the weighing sensor (3c) and the weighing sensor (3d) are distributed in a rectangular shape;

the weighing sensor (3) is installed on the air floatation upper plate (2a), the aligning and inclination adjusting workbench (4) is installed on the weighing sensor (3), the aligning and inclination adjusting workbench (4) is located at the central position of the air floatation shaft system (2), and the hydraulic chuck (5) is installed at the central position of the aligning and inclination adjusting workbench (4); the left upright post transverse guide rail (6a) and the right upright post transverse guide rail (6b) are symmetrically distributed on two sides of the air floatation shaft system (2) and are fixedly arranged on the base (1); a left upright vertical guide rail (7a) is arranged on a left upright transverse guide rail (6a), a right upright vertical guide rail (7b) is arranged on a right upright transverse guide rail (6b), a left lower transverse measuring bar (8a) and a left upper transverse measuring bar (8b) are horizontally nested on the left upright vertical guide rail (7a), a right lower transverse measuring bar (8c) and a right upper transverse measuring bar (8d) are horizontally nested on the right upright vertical guide rail (7b), a left lower telescopic inductive sensor (9a) is arranged at the end part of the left lower transverse measuring bar (8a), a left upper telescopic inductive sensor (9b) is arranged at the end part of the left upper transverse measuring bar (8b), a right upper lever inductive sensor (9c) is arranged at the end part of the right upper transverse measuring bar (8c), a right lower lever inductive sensor (9d) is arranged at the end part of the right lower transverse measuring bar (8d), the measured rotor (10) is arranged on the hydraulic chuck (5).

2. The aircraft engine rotor assembly measuring device based on four-point weighing as claimed in claim 1, wherein: the weighing sensor is an SBS shear beam type weighing sensor with a Mettler-Tollido structure.

3. A four-point weighing-based dual-target optimization method for rotor assembly of an aircraft engine, which is based on the four-point weighing-based rotor assembly measuring device of the aircraft engine as claimed in claim 1, and is characterized in that: the method comprises the following steps:

step 1: aligning and adjusting the aligning and inclination adjusting workbench (4), ensuring that the centroid of the assembly reference surface is concentric with the rotation axis of the aligning and inclination adjusting workbench (4), ensuring that the assembly reference surface is parallel to the plane of the aligning and inclination adjusting workbench (4), ensuring that the assembly reference is the bottom surface of the bottom layer rotor, taking the rotation axis of the air floating axis system (2) as the Z axis, taking the intersection point of the rotation axis and the upper surface of the air floating upper plate (2a) as the origin of coordinates, taking a straight line which passes through the origin of coordinates and is transversely parallel to the base (1) as the X axis, and taking a straight line which passes through the origin of coordinates and is perpendicular to the X axis as the Y axis;

step 2: measuring the concentricity and the parallelism of each single-stage rotor to obtain the concentricity and the parallelism of the measured rotor (10);

and step 3: measuring the mass center coordinate of each single-stage rotor to obtain the mass center coordinate of the measured rotor (10);

and 4, step 4: performing double-target optimization on the coaxiality and the mass center offset of the multistage rotor to obtain the optimal assembly angle of the measured rotor (10);

and 5: assembling the single-stage rotors together according to the optimal assembly angle of the rotors at each stage;

step 6: and detecting the coaxiality and the mass center offset of the assembly to ensure that the assembly requirement index is met.

4. The dual-target optimization method for the rotor assembly of the aircraft engine based on the four-point weighing method as claimed in claim 3, wherein the method comprises the following steps: the step 1 of aligning and tilt adjusting of the aligning and tilt adjusting workbench (4) is as follows:

step 1.1: a measured rotor (10) is placed on an aligning and inclination adjusting workbench (4) and fixed through a hydraulic chuck (5), and a right lower lever type inductance sensor (9c) and a right upper lever type inductance sensor (9d) are in contact with a radial assembly reference surface of the measured rotor (10) and used for aligning; contacting a left lower telescopic inductive sensor (9a) and a left upper telescopic inductive sensor (9b) with an axial assembly reference surface of a measured rotor (10) for adjusting inclination;

step 1.2: an air flotation shaft system (2) drives a measured rotor (10) to rotate at a constant speed of 6r/min to 10r/min through an aligning and inclination adjusting workbench (4), a right lower lever type inductive sensor (9c) and a right upper lever type inductive sensor (9d) perform equal-interval sampling on a radial assembly reference surface of the measured rotor (10), a left lower telescopic inductive sensor (9a) and a left upper telescopic inductive sensor (9b) perform equal-interval sampling on an axial assembly reference surface of the measured rotor (10), and the number of sampling points meets 1000-2000 points per circle; performing least square circle fitting on the sampled data on the radial assembly reference surface of the measured rotor (10) to obtain an eccentricity, and performing least square plane fitting on the sampled data on the axial assembly reference surface of the measured rotor (10) to obtain an inclination;

step 1.3: and adjusting the aligning knob of the aligning and tilt-adjusting workbench (4) according to the magnitude and the angle of the eccentric amount, and adjusting the tilt-adjusting knob of the aligning and tilt-adjusting workbench (4) according to the magnitude and the angle of the tilt amount until the aligning and tilt-adjusting workbench (4) meets the requirements that the magnitude of the eccentric amount of the radial reference surface is in the range of 0 to 3 mu m and the magnitude of the tilt amount of the axial reference surface is in the range of 0 to 2'.

5. The dual-target optimization method for the rotor assembly of the aircraft engine based on the four-point weighing method as claimed in claim 3, wherein the method comprises the following steps: the step 2 specifically comprises the following steps:

step 2.1: a right lower lever type inductive sensor (9c) and a right upper lever type inductive sensor (9d) are in contact with a radial assembly measuring surface of a measured rotor (10), a left lower telescopic inductive sensor (9a) and a left upper telescopic inductive sensor (9b) are in contact with an axial assembly measuring surface of the measured rotor (10), and an air floatation shaft system (2) rotates at a constant speed of 6r/min to 10 r/min;

step 2.2: sampling at equal intervals on a radial assembly measuring surface of a measured rotor (10) by adopting a right lower lever type inductive sensor (9c) and a right upper lever type inductive sensor (9d), sampling at equal intervals on an axial assembly measuring surface of the measured rotor (10) by adopting a left lower telescopic inductive sensor (9a) and a left upper telescopic inductive sensor (9b), and counting the number of sampling points to meet 1000-2000 points per circle;

step 2.3: and carrying out least square circle fitting on the sampled data on the radial assembly measuring surface of the measured rotor (10) to obtain concentricity, carrying out least square plane fitting on the sampled data on the axial assembly measuring surface of the measured rotor (10) to obtain parallelism, and recording corresponding phase angles of all points by adopting a circular grating reading head (2 e).

6. The dual-target optimization method for the rotor assembly of the aircraft engine based on the four-point weighing method as claimed in claim 3, wherein the method comprises the following steps: the step 3 specifically comprises the following steps:

step 3.1: taking the rotation axis of the air floatation shaft system (2) as a total reference, and installing a weighing sensor (3a), a weighing sensor (3b), a weighing sensor (3c) and a weighing sensor (3d) on the table top of an air floatation upper plate (2a) in a rectangular distribution manner;

step 3.2: symmetrically arranging a weighing sensor (3a) and a weighing sensor (3d) on two sides of an X axis, wherein the distance between connecting lines of bearing points of the weighing sensor (3a) and the weighing sensor (3d) is H, and the connecting lines are parallel to a Y axis; the weighing sensor (3b) and the weighing sensor (3c) are symmetrically arranged on two sides of an X axis, a connecting line of bearing points of the weighing sensor (3b) and the weighing sensor (3c) is parallel to the Y axis, the connecting line distance of the bearing points of the weighing sensor (3a) and the weighing sensor (3b) is L and is parallel to the X axis, and the weighing sensor (3a) and the weighing sensor (3b) are symmetrical relative to the Y axis;

step 3.3: measuring to obtain the barycenter coordinate of the measured rotor (10); the coordinates of the center of mass of the measured rotor (10) are expressed by:

wherein M is the weight of the measured rotor (10), F₁、F₂、F₃And F₄Difference between no load and load of load cell (3a), load cell (3b), load cell (3c) and load cell (3d), G_xIs the abscissa of the centroid of the measured rotor (10); g_yIs the ordinate of the centroid of the measured rotor (10).

7. The dual-target optimization method for the rotor assembly of the aircraft engine based on the four-point weighing method as claimed in claim 3, wherein the method comprises the following steps: the step 4 specifically comprises the following steps:

step 4.1: establishing a calculation model for predicting the concentricity and the mass center coordinates of the rotor after the multi-stage rotor is transferred, and expressing the calculation model by the following formula:

wherein, XQ_iAnd XH_iAssembly face centroid coordinate vectors, ZQ, before and after assembly of the i-th rotor_iAnd ZH_iRespectively are mass center coordinate vectors before and after the i-th-stage rotor is assembled; rz_iA rotation matrix of the ith-stage rotor around the Z axis of the top surface of the ith-1-stage rotor; ry_iA rotation matrix of the ith-stage rotor around a total reference Y axis; h is_iParallelism measured for the i-th rotor; c. C_iConcentricity measured for the i-th stage rotor; h_iIs the ith stage rotor height; theta_ziFor the ith-stage rotor to rotate around the Z axis on the top surface of the ith-1 stage rotorThe angle of rotation;

determining the concentricity of the ith-stage rotor after the multi-stage rotor is matched, and expressing the concentricity of the ith-stage rotor after the multi-stage rotor is matched by the following formula:

wherein, CH_iFor the concentricity, XH, of i-th rotor after the rotor has been rotatably coupled to more than one rotor_i(x)Assembling the abscissa of the face centroid after the i-th-stage rotor is assembled; XH_i(y)Assembling the ordinate of the face centroid for the i-th rotor after assembly;

determining the centroid coordinate vector of the whole assembly body after the assembly of the multistage rotors, and representing the centroid coordinate vector of the whole assembly body after the assembly of the multistage rotors by the following formula:

wherein ZH is the mass center coordinate vector of the whole assembly body after the assembly of the multistage rotors, ZH_iAssembling a centroid coordinate vector for the ith-stage rotor; m_iIs the i-th stage rotor weight;

step 4.2: establishing an optimization target which is a dual target and respectively refers to the whole coaxiality and mass center offset of the assembled multi-stage rotor, wherein the coaxiality refers to the maximum value of the concentricity of each single-stage rotor after the rotor is assembled, and the coaxiality is expressed by the following formula:

c＝max{CH_i,i＝1,2,...,n} (7)

wherein c is the coaxiality, and n is the number of rotor stages;

the centroid offset is the perpendicular distance of the centroid to the longitudinal axis, and is represented by the following equation:

wherein e is the centroid offset, ZH_xAs the abscissa of the centroid of the entire assembly, ZH_yIs a whole assembly bodyThe ordinate of the centroid;

step 4.3: establishing a dual target minimization function, which is expressed by the following formula:

wherein the content of the first and second substances,in order to be the objective function, the target function,is a vector formed by the assembly angles of the single-stage rotors; theta_znThe angle of the nth-stage rotor rotating around the normal axis of the top surface of the nth-1 stage rotor,optimizing a function for a single target based on coaxiality;a single objective optimization function based on centroid offset;

step 4.4: converting the dual-target minimization function into a fitness function of the genetic algorithm, and expressing the fitness function of the genetic algorithm by the following formula:

wherein e is_△For the minimum of a single-objective optimization function based on centroid offset, c_△Is the minimum value of a single-target optimization function based on coaxiality;

step 4.5: obtaining the optimal transfer angle theta of each stage of rotor through a genetic algorithm_ziSo that the coaxiality and centroid displacement approach the minimum values for individual target optimization.

Technical Field

The invention relates to the technical field of mechanical transfer, in particular to an aeroengine rotor assembly measuring device based on four-point weighing and a dual-target optimization method.

Background

The aircraft engine is the most precise and complex rotating machine in the modern industry, and the assembly technology is the final process stage in the engine manufacturing process, particularly the core component represented by a high-pressure compressor rotor, and the assembly quality of the aircraft engine directly influences the high-speed operation stability of the engine.

The two main reasons for the faults of the aero-engine are that the rotor is not in alignment with the rotor and the rotor is not balanced, and how to realize the synchronous optimization of the rotor on the amount of alignment and the amount of unbalance in the assembling stage is a key common technical problem which troubles the manufacturing industry of the aero-engine at home and abroad for a long time.

At present, the coaxiality of assembled multistage rotors is improved mainly by changing the assembling angles of the rotors at all levels by domestic and foreign research teams, so that the misalignment of the rotors is reduced, and the Harbin industry university provides an aircraft engine rotor assembling method and device based on multi-component concentricity optimization. Publication No.: CN 103790648A. The method comprises the steps of firstly, respectively measuring the radial error and the inclination error of the assembly surface of each single-stage rotor, then calculating the influence weight of each rotor on the whole coaxiality of the assembled rotor, and finally, carrying out vector optimization on the weight of each rotor to obtain the optimal assembly angle of each rotor. The method has problems that: the influence of the quality characteristic of the rotor on the assembly quality is not considered, and the unbalance of the rotor cannot be optimized while the medium quantity of the rotor does not reach the standard.

The Shenyang dawn aircraft engine finite responsibility company of China aviation proposes an assembly process method for a low-pressure turbine rotor of an aircraft engine, and the process method is used for assembling the low-pressure turbine rotor of the aircraft engine. Publication No.: CN 109356662A. The method comprises the steps of measuring, grinding, maintaining and fitting the assembly positions by controlling the unbalance amount of a sealing ring, the matching amount of the sealing ring and a low-pressure first-stage turbine disc, measuring the form and position tolerance of a low-pressure first-stage turbine disc and a low-pressure second-stage turbine disc, assembling the low-pressure second-stage turbine disc and a low-pressure turbine shaft layer by layer on an installation base, checking whether the assembled form and position tolerance is qualified layer by layer, assembling the low-pressure first-stage turbine disc and the sealing ring if the assembled form and position tolerance is qualified, tightening through a connecting bolt by means of an adapter and a positioning tool, and checking that the assembled low-pressure first-stage. The method has problems that: the optimal assembly phase of each stage of rotor cannot be directly given, the assembly position can only be fitted layer by layer according to the form and position tolerance of the rotor, and the assembly position fitting of the next stage of rotor can be carried out only after the form and position tolerance of the assembled rotor is checked to be qualified, so that the assembly efficiency is low.

At present, the internal engine rotor assembly technology still depends on the skill level and experience of operators to a great extent, and an optimization method for effectively guiding the assembly of the aircraft engine rotor at a high speed is lacked, so that the indexes of misalignment and unbalance of the rotor are met, and the assembly efficiency and the one-time assembly qualification rate of the aircraft engine rotor are greatly improved.

Disclosure of Invention

The invention provides an aeroengine rotor assembly measuring device based on four-point weighing and a double-target optimization method for solving the problem that rotors are not in alignment and unbalanced, and provides the following technical scheme:

an aircraft engine rotor assembly measuring device based on four-point weighing, the device comprising: the device comprises a base 1, an air floatation shaft system 2, a weighing sensor 3, an aligning and inclination adjusting workbench 4, a hydraulic chuck 5, a left upright transverse guide rail 6a, a right upright transverse guide rail 6b, a left upright vertical guide rail 7a, a right upright vertical guide rail 7b, a left lower transverse measuring rod 8a, a left upper transverse measuring rod 8b, a right lower transverse measuring rod 8c, a right upper transverse measuring rod 8d, a left lower telescopic inductance sensor 9a, a left upper telescopic inductance sensor 9b, a right lower lever inductance sensor 9c, a right upper lever inductance sensor 9d and a measured rotor 10, wherein the air floatation shaft system 2 is installed on the central point of the base 1;

the air floatation shaft system 2 comprises an air floatation upper plate 2a, an air floatation main shaft 2b, an air floatation lower plate 2c, a circular grating ruler 2d, a circular grating reading head 2e, a motor stator 2f and an electronic rotor 2 g; the air floatation upper plate 2a is arranged at the upper end of an air floatation main shaft 2b, the air floatation lower plate 2c is arranged at the lower end of the air floatation main shaft 2b, the circular grating ruler 2d is arranged on the outer wall of the side surface of the air floatation lower plate 2a, the circular grating reading head 2e is arranged on the inner wall of the base 1, and the circular grating reading head 2e is transversely aligned with the circular grating ruler 2 d;

the weighing sensor 3 comprises a weighing sensor 3a, a weighing sensor 3b, a weighing sensor 3c and a weighing sensor 3d, and the weighing sensor 3a, the weighing sensor 3b, the weighing sensor 3c and the weighing sensor 3d are distributed in a rectangular shape;

the weighing sensor 3 is arranged on the air floatation upper plate 2a, the aligning and inclination adjusting workbench 4 is arranged on the weighing sensor 3, the aligning and inclination adjusting workbench 4 is positioned at the central position of the air floatation shaft system 2, and the hydraulic chuck 5 is arranged at the central position of the aligning and inclination adjusting workbench 4; the left upright post transverse guide rail 6a and the right upright post transverse guide rail 6b are symmetrically distributed on two sides of the air floatation shaft system 2 and are fixedly arranged on the base 1; the left vertical column guide rail 7a is installed on the left vertical column transverse guide rail 6a, the right vertical column guide rail 7b is installed on the right vertical column transverse guide rail 6b, a left lower transverse measuring rod 8a and a left upper transverse measuring rod 8b are horizontally nested on the left vertical column guide rail 7a, a right lower transverse measuring rod 8c and a right upper transverse measuring rod 8d are horizontally nested on the right vertical column guide rail 7b, a left lower telescopic inductive sensor 9a is installed at the end part of the left lower transverse measuring rod 8a, a left upper telescopic inductive sensor 9b is installed at the end part of the left upper transverse measuring rod 8b, an upper right lever inductive sensor 9c is installed at the end part of the right upper transverse measuring rod 8c, a right lower lever inductive sensor 9d is installed at the end part of the right lower transverse measuring rod 8d, and a measured rotor 10 is installed on the hydraulic chuck 5.

Preferably, the load cell is a SBS shear Beam load cell of Mettler-Toriledo.

A four-point weighing-based dual-target optimization method for rotor assembly of an aircraft engine is based on a four-point weighing-based rotor assembly measuring device of the aircraft engine and comprises the following steps:

step 1: aligning and adjusting the aligning and inclination adjusting workbench 4, ensuring that the centroid of the assembly reference surface is concentric with the rotation axis of the shaft system of the aligning and inclination adjusting workbench 4, ensuring that the assembly reference surface is parallel to the plane of the aligning and inclination adjusting workbench 4, ensuring that the assembly reference is the bottom surface of the bottom layer rotor, taking the rotation axis of the air floatation shaft system 2 as the Z axis, taking the intersection point of the rotation axis and the upper surface of the air floatation upper plate 2a as the origin of coordinates, taking the straight line which passes through the origin of coordinates and is transversely parallel to the base 1 as the X axis, and taking the straight line which passes through the origin of coordinates and is perpendicular to the X axis as the Y axis;

step 2: measuring the concentricity and the parallelism of each single-stage rotor to obtain the concentricity and the parallelism of the measured rotor 10;

and step 3: measuring the mass center coordinate of each single-stage rotor to obtain the mass center coordinate of the measured rotor 10;

and 4, step 4: performing double-target optimization on the coaxiality and the mass center offset of the multistage rotor to obtain the optimal assembly angle of the measured rotor 10;

and 5: assembling the single-stage rotors together according to the optimal assembly angle of the rotors at each stage;

step 6: and detecting the coaxiality and the mass center offset of the assembly to ensure that the assembly requirement index is met.

Preferably, the step 1 of aligning and tilt adjusting the aligning and tilt adjusting table 4 specifically comprises:

step 1.1: the measured rotor 10 is placed on the aligning and inclination adjusting workbench 4 and fixed through the hydraulic chuck 5, and the right lower lever type inductive sensor 9c and the right upper lever type inductive sensor 9d are in contact with the radial assembly reference surface of the measured rotor 10 and used for aligning; contacting a left lower telescopic inductive sensor 9a and a left upper telescopic inductive sensor 9b with an axial assembly reference surface of a measured rotor 10 for adjusting inclination;

step 1.2: the air flotation shafting 2 drives the measured rotor 10 to rotate at a constant speed of 6r/min to 10r/min through the aligning and inclination adjusting workbench 4, the right lower lever type inductive sensor 9c and the right upper lever type inductive sensor 9d perform equal-interval sampling on the radial assembly reference surface of the measured rotor 10, the left lower telescopic inductive sensor 9a and the left upper telescopic inductive sensor 9b perform equal-interval sampling on the axial assembly reference surface of the measured rotor 10, and the number of sampling points meets 1000 to 2000 points per circle; performing least square circle fitting on the sampled data on the radial assembly datum plane of the measured rotor 10 to obtain an eccentricity, and performing least square plane fitting on the sampled data on the axial assembly datum plane of the measured rotor 10 to obtain an inclination;

step 1.3: and adjusting the aligning knob of the aligning and tilt-adjusting workbench 4 according to the magnitude and the angle of the eccentric amount, and adjusting the tilt-adjusting knob of the aligning and tilt-adjusting workbench 4 according to the magnitude and the angle of the tilt amount until the aligning and tilt-adjusting workbench 4 meets the requirements that the magnitude of the eccentric amount of the radial reference surface is in the range of 0 to 3 mu m and the magnitude of the tilt amount of the axial reference surface is in the range of 0 to 2'.

Preferably, the step 2 specifically comprises:

step 2.1: contacting a right lower lever type inductive sensor 9c and a right upper lever type inductive sensor 9d with a radial assembly measuring surface of a measured rotor 10, contacting a left lower telescopic inductive sensor 9a and a left upper telescopic inductive sensor 9b with an axial assembly measuring surface of the measured rotor 10, and enabling an air floatation shaft system 2 to rotate at a constant speed of 6r/min to 10 r/min;

step 2.2: sampling at equal intervals on the radial assembly measuring surface of the measured rotor 10 by adopting a right lower lever type inductive sensor 9c and a right upper lever type inductive sensor 9d, sampling at equal intervals on the axial assembly measuring surface of the measured rotor 10 by adopting a left lower telescopic inductive sensor 9a and a left upper telescopic inductive sensor 9b, and counting the number of sampling points to meet 1000-2000 points per circle;

step 2.3: and carrying out least square circle fitting on the sampled data on the radial assembly measuring surface of the measured rotor 10 to obtain concentricity, carrying out least square plane fitting on the sampled data on the axial assembly measuring surface of the measured rotor 10 to obtain parallelism, and simultaneously recording corresponding phase angles of all points by adopting a circular grating reading head 2 e.

Preferably, the step 3 specifically comprises:

step 3.1: taking the rotation axis of the air floatation shaft system 2 as a total reference, and installing a weighing sensor 3a, a weighing sensor 3b, a weighing sensor 3c and a weighing sensor 3d on the table top of an air floatation upper plate 2a in a rectangular distribution;

step 3.2: symmetrically arranging a weighing sensor 3a and a weighing sensor 3d on two sides of an X axis, wherein the distance between connecting lines of bearing points of the weighing sensor 3a and the weighing sensor 3d is H and is parallel to a Y axis; the weighing sensor 3b and the weighing sensor 3c are symmetrically arranged on two sides of an X axis, a connecting line of bearing points of the weighing sensor 3b and the weighing sensor 3c is parallel to the Y axis, the distance between the connecting lines of the bearing points of the weighing sensor 3a and the weighing sensor 3b is L and is parallel to the X axis, and the weighing sensor 3a and the weighing sensor 3b are symmetrical relative to the Y axis;

step 3.3: measuring to obtain the barycenter coordinate of the measured rotor 10; the barycentric coordinates of the measured rotor 10 are represented by:

wherein M is the weight of the measured rotor 10, F₁、F₂、F₃And F₄Difference between no-load and load of load cell 3a, load cell 3b, load cell 3c and load cell 3d, G_xIs the abscissa of the centroid of the measured rotor 10; g_yIs the ordinate of the centroid of the measured rotor 10.

Preferably, the step 4 specifically includes:

step 4.1: establishing a calculation model for predicting the concentricity and the mass center coordinates of the rotor after the multi-stage rotor is transferred, and expressing the calculation model by the following formula:

wherein, XQ_iAnd XH_iAssembly face centroid coordinate vectors, ZQ, before and after assembly of the i-th rotor_iAnd ZH_iRespectively are mass center coordinate vectors before and after the i-th-stage rotor is assembled; rz_iA rotation matrix of the ith-stage rotor around the Z axis of the top surface of the ith-1-stage rotor; ry_iA rotation matrix of the ith-stage rotor around a total reference Y axis; h is_iParallelism measured for the i-th rotor; c. C_iConcentricity measured for the i-th stage rotor; h_iIs the ith stage rotor height; theta_ziThe angle of the ith-stage rotor rotating around the Z axis on the top surface of the ith-1-stage rotor;

determining the concentricity of the ith-stage rotor after the multi-stage rotor is matched, and expressing the concentricity of the ith-stage rotor after the multi-stage rotor is matched by the following formula:

wherein, CH_iFor the concentricity, XH, of i-th rotor after the rotor has been rotatably coupled to more than one rotor_i(x)Assembling the abscissa of the face centroid after the i-th-stage rotor is assembled; XH_i(y)Assembling the ordinate of the face centroid for the i-th rotor after assembly;

determining the centroid coordinate vector of the whole assembly body after the assembly of the multistage rotors, and representing the centroid coordinate vector of the whole assembly body after the assembly of the multistage rotors by the following formula:

wherein ZH is the mass center coordinate vector of the whole assembly body after the assembly of the multistage rotors, ZH_iAssembling a centroid coordinate vector for the ith-stage rotor; m_iIs the i-th stage rotor weight;

step 4.2: establishing an optimization target which is a dual target and respectively refers to the whole coaxiality and mass center offset of the assembled multi-stage rotor, wherein the coaxiality refers to the maximum value of the concentricity of each single-stage rotor after the rotor is assembled, and the coaxiality is expressed by the following formula:

c＝max{CH_i,i＝1,2,...,n}(7)

wherein c is the coaxiality, and n is the number of rotor stages;

the centroid offset is the perpendicular distance of the centroid to the longitudinal axis, and is represented by the following equation:

wherein e is the centroid offset, ZH_xAs the abscissa of the centroid of the entire assembly, ZH_yIs the ordinate of the mass center of the whole assembly body;

step 4.3: establishing a dual target minimization function, which is expressed by the following formula:

wherein the content of the first and second substances,in order to be the objective function, the target function,is a vector formed by the assembly angles of the single-stage rotors; theta_znThe angle of the nth-stage rotor rotating around the normal axis of the top surface of the nth-1 stage rotor,optimizing a function for a single target based on coaxiality;a single objective optimization function based on centroid offset;

step 4.4: converting the dual-target minimization function into a fitness function of the genetic algorithm, and expressing the fitness function of the genetic algorithm by the following formula:

wherein e is_△For the minimum of a single-objective optimization function based on centroid offset, c_△For a single-objective optimization function based on coaxialityA minimum value;

step 4.5: obtaining the optimal transfer angle theta of each stage of rotor through a genetic algorithm_ziSo that the coaxiality and centroid displacement approach the minimum values for individual target optimization.

The invention has the following beneficial effects:

the assembly optimization method comprehensively considers the geometric and quality characteristics of the multistage rotor, can realize the dual-target synchronous optimization of the overall coaxiality and the mass center offset of the assembled multistage rotor, can control the assembly axis not to generate transition bending, and can control the unbalance of the rotor within an allowable range.

The existing aeroengine rotor assembly measuring device can only extract geometric information centroid coordinates, concentricity, parallelism, height and the like of a measured rotor, and cannot extract the total mass and centroid coordinates of the mass information of the measured rotor. The measuring device can realize the integrated measurement of the geometric quantity and the quality information of the measured rotor.

Drawings

FIG. 1 is a flow chart of a four-point weighing-based dual-target optimization method for rotor assembly of an aircraft engine;

FIG. 2 is a schematic view of an aircraft engine rotor assembly measurement device based on four-point weighing;

FIG. 3 is a schematic view of the arrangement of the measurement air-floating axis system and the circular grating;

FIG. 4 is a schematic view of a load cell distribution;

fig. 5 is a schematic diagram comparing the pre-optimization fitting effect with the post-optimization fitting effect. Fig. 5-a shows the assembly effect before optimization, and fig. 5-b shows the assembly effect after optimization.

Detailed Description

The present invention will be described in detail with reference to specific examples.