阅读说明：本技术 一种基于三点称重的航空发动机转子装配测量装置及三目标优化方法 (Three-point weighing-based aeroengine rotor assembly measuring device and three-target optimization method ) 是由 陈越 崔继文 谭久彬 于 2019-09-25 设计创作，主要内容包括：本发明是一种基于三点称重的航空发动机转子装配测量装置及三目标优化方法。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；基于三点称重测量装置,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、不平衡量和转动惯量为三优化目标,通过遗传寻优,得到各级转子的最优装配角度；基于扭杆测量装置,得到装配体的纵轴转动惯量。本发明可有效解决航空发动机转子装配后同轴度、不平衡量和转动惯量的超标问题,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 three-point weighing and a three-target optimization method. 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 three-point weighing measuring device; based on a rotor assembly pose transfer model, the optimal assembly angles of the rotors at all levels are obtained by taking the coaxiality, the unbalance amount and the rotational inertia of a rotor assembly body as three optimization targets through genetic optimization; based on the torsion bar measuring device, the longitudinal axis moment of inertia of the assembly body is obtained. The invention can effectively solve the problem of over-standard coaxiality, unbalance and rotational inertia of the rotor of the aero-engine after assembly, and has the characteristics of integrated measurement of geometric and mass characteristics of the rotor, high qualification rate of one-time assembly and reduction of engine vibration.)

1. The utility model provides an aeroengine rotor assembly measuring device based on three point weighing which characterized by: the device comprises: the device comprises a base (1), an air floatation shaft system (2), a weighing sensor (3), a leveling and inclining platform (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);

the air-floating shafting (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 cylinder (2f), a shifting fork (2g), a permanent magnet (2h), a coil (2i), a photoelectric counter (2j), a torsion bar (2k) and a torsion bar locking device (2 l);

the weighing sensor (3) comprises a weighing sensor (3a), a weighing sensor (3b) and a weighing sensor (3c), and the weighing sensor (3a), the weighing sensor (3b) and the weighing sensor (3c) are distributed in an isosceles triangle shape;

the air-floating type air-floating device is characterized in that an air-floating upper plate (2a) is installed on the upper end part of an air-floating main shaft (2b), an air-floating lower plate (2c) is installed on the lower end part of the air-floating main shaft (2b), a circular grating ruler (2d) is installed on the outer wall of the side surface of the air-floating lower plate (2c), a circular grating reading head (2e) is installed on the inner wall of a base (1) and is transversely aligned with the circular grating ruler (2d), an air cylinder (2f) is installed on the inner wall of the base (1), a shifting fork (2g) is installed on the outer wall of the air-floating lower plate (2c), a permanent magnet (2h) is installed on the outer ring of the air-floating main shaft (2b), a coil (2i) is installed on the outer ring of the main shaft (2b), the coil (2i) is longitudinally aligned with the permanent magnet (2h), an photoelectric counter (, the torsion bar locking device (2l) is arranged at the bottom of the base (1), the torsion bar locking device (2l) is symmetrically distributed at two sides of a torsion bar (2k), the weighing sensor (3) is arranged on an air-floating upper plate (2a), the leveling and inclination-adjusting platform (4) is arranged on the weighing sensor (3), the leveling and inclination-adjusting platform (4) is positioned at the central position of an air-floating shaft system (2), the hydraulic chuck (5) is arranged at the central position of the leveling and inclination-adjusting platform (4), the left upright transverse guide rail (6a) and the right upright transverse guide rail (6b) are symmetrically distributed at two sides of the air-floating shaft system (2) and are fixedly arranged on the base (1), the left upright vertical guide rail (7a) is arranged on the left upright transverse guide rail (6a), the right upright vertical guide rail (7b) is arranged on the right upright transverse guide rail (6b), the left lower transverse measuring bar (8a) and the left upper transverse measuring bar (8b) are horizontally nested on the left upright vertical guide rail (, the lower right transverse measuring rod (8c) and the upper right transverse measuring rod (8d) are horizontally nested on the vertical guide rail (7b) of the upright column at the right side, the lower left telescopic inductive sensor (9a) is installed at the end part of the lower left transverse measuring rod (8a), the upper left telescopic inductive sensor (9b) is installed at the end part of the upper left transverse measuring rod (8b), the upper right lever inductive sensor (9c) is installed at the end part of the upper right transverse measuring rod (8c), the lower right lever inductive sensor (9d) is installed at the end part of the lower right transverse measuring rod (8d), and the measured rotor (10) is installed on the hydraulic chuck (5).

2. The three-point weighing-based aeroengine rotor assembly measuring device as defined in claim 1, wherein: the weighing sensor is an SBS shear beam type weighing sensor with a Mettler-Tollido structure.

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

step 1: aligning and adjusting the leveling and inclination adjusting platform (4), ensuring that the centroid of the assembly reference surface is concentric with the rotation axis of the leveling and inclination adjusting platform (4), ensuring that the assembly reference surface is parallel to the plane of the leveling and inclination adjusting platform (4), ensuring that the assembly reference is the bottom surface of the bottom layer rotor, taking the rotation axis of the air floatation axis 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 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: optimizing three targets of coaxiality, unbalance and longitudinal axis moment of inertia 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, the mass center offset and the rotational inertia of the assembly to ensure that the assembly requirement indexes are met.

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

step 1.1: a measured rotor (10) is placed on a leveling and inclination-adjusting platform (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 a leveling and inclination adjusting platform (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 leveling and inclination adjusting platform (4) according to the size and the angle of the eccentric amount, and adjusting the inclination adjusting knob of the leveling and inclination adjusting platform (4) according to the size and the angle of the inclination amount until the leveling and inclination adjusting platform (4) meets the requirements that the size of the eccentric amount of the radial reference surface is in the range of 0 to 3 mu m and the size of the inclination amount of the axial reference surface is in the range of 0 to 2'.

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

step 3.1: the rotation center of the air floatation shaft system (2) is taken as a total reference, and the weighing sensor (3a), the weighing sensor (3b) and the weighing sensor (3c) are distributed in an isosceles triangle and are arranged on the table surface of the air floatation upper plate (2 a);

step 3.2: the bearing point of the weighing sensor (3a) is coincided with the X axis, and the distance from the origin of coordinates is L₁(ii) a The weighing sensors (3b) and (3c) are symmetrically arranged on two sides of an X axis, a connecting line of bearing points of the weighing sensors (3b) and (3c) is parallel to a Y axis, and the distance between the bearing point of the weighing sensor (3b) and the Y axis is L₃At a distance L from the X-axis₄(ii) a The distance between the bearing point of the weighing sensor (3c) and the Y axis is L₂At a distance L from the X-axis₅；

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、F₂And F₃Respectively a weighing sensor (3a), a weighing sensor (3b) and a weighing sensorThe difference value between the no-load and the loading of the sensor (3c), and Gx is the abscissa of the centroid of the measured rotor (10); gy is the ordinate of the centroid of the measured rotor (10).

7. The three-point weighing-based three-target optimization method for the assembly of the aircraft engine rotor as claimed in claim 3, wherein the three-point weighing-based three-target optimization 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_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;

determining the moment of inertia of the longitudinal shaft of the ith-stage rotor after the multistage rotor is assembled, and expressing the moment of inertia of the longitudinal shaft of the ith-stage rotor after the multistage rotor is assembled by the following formula:

JH_i＝(ZH_i(x) ²+ZH_i(y) ²)M_i(7)

wherein JH_iThe moment of inertia of the longitudinal axis of the ith-stage rotor after the multistage rotor is assembled;

step 4.2: establishing an optimization target, wherein the optimization target is three targets, namely, the unbalance amount of the whole coaxiality and the moment of inertia of the longitudinal axis after the multi-stage rotor is assembled, the coaxiality is the maximum value of the concentricity of each single-stage rotor after the rotors are assembled, and the coaxiality is calculated by the following formula:

c＝max{CH_i,i＝1,2,...,n}(8)

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

the unbalance amount is the product of the total mass of the assembly body and the mass center offset, and the mass center offset and the unbalance amount are represented by the following formula:

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

the moment of inertia of the longitudinal axis, which is the product of the total mass of the fitting body and the square of the offset of the center of mass, is expressed by the following equation:

wherein J is the moment of inertia of the longitudinal axis;

step 4.3: establishing a tri-objective 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;for a single objective optimization function based on centroid offsets,a single objective optimization function based on the amount of unbalance is represented,representing a single objective optimization function based on the moment of inertia;

step 4.4: converting the three-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, c_△For the minimum value of the coaxiality-based single-objective optimization function, U_△For the minimum of a single-objective optimization function based on the amount of unbalance, J_△Is the minimum value of a single-target optimization function based on the moment of inertia;

step 4.5: obtaining the optimal transfer angle theta of each stage of rotor through a genetic algorithm_ziAnd the coaxiality, the unbalance amount and the rotational inertia are close to the minimum value of each single target optimization, so that the coaxiality, the unbalance amount and the rotational inertia of the rotor are simultaneously optimized under the same assembly reference.

8. The three-point weighing-based three-target optimization method for the assembly of the aircraft engine rotor as claimed in claim 3, wherein the three-point weighing-based three-target optimization method comprises the following steps: measuring the polarity of the longitudinal axis rotational inertia of the assembly, and measuring the period T of the idle pendulum of the air-floating shafting (2)₀Moment of inertia J of the turntable₀＝AT₀ ²Measuring the common runout period Ts of a standard sample piece and the air floatation shaft system (2), wherein the rotational inertia of the standard sample piece is Js, and obtaining a proportionality coefficientMeasuring the common pendulum period T of the measured rotor (10) and the air-floating shaft system (2), and measuring the longitudinal axis moment of inertia J of the measured assembly body_c＝A(T²-T₀ ²)。

9. The three-point weighing based three-target optimization method for the assembly of the aeroengine rotor as claimed in claim 8, wherein the three-point weighing based three-target optimization method comprises the following steps: the torsion bar (2k) is locked through the torsion bar locking device (2l), and the air cylinder (2f) pushes the shifting fork (2g) to drive the air floatation shaft system (2) to generate micro angular displacement; the cylinder (2f) is loosened, and the air floatation shaft system (2) generates periodic compound pendulum motion under the action of the elastic restoring force of the torsion bar (2 k); and the photoelectric counter (2j) records the runout period of the air floatation shaft system (2).

Technical Field

The invention relates to the technical field of mechanical transfer, in particular to an aeroengine rotor assembly measuring device based on three-point weighing and a three-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 rotor coaxiality, the rotor unbalance and the overlarge rotary inertia are all important reasons for causing faults of the aero-engine, and how to realize the synchronous optimization of the rotor coaxiality, the unbalance and the rotary inertia in the assembling stage is a key common technical problem which puzzles the manufacturing industry of the aero-engine at home and abroad for a long time.

At present, research teams at home and abroad mainly improve the assembly quality of multi-stage rotors by changing the assembly phase of each stage of rotor, and Harbin university of industry proposes an aeroengine rotor assembly method and device based on multi-component concentricity optimization (the aeroengine rotor assembly method and device based on multi-component concentricity optimization). 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 optimization of the unbalance amount and the rotational inertia of the rotor cannot be considered while the coaxiality of the rotor reaches the standard.

China aviation Shenyang dawn aeroengine Limited liability company provides an assembly process method for an aeroengine low-pressure turbine rotor (a process method for assembling the aeroengine low-pressure turbine rotor, publication number: 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 coaxiality, the unbalance amount and the rotational inertia index of the rotor are simultaneously 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 three-point weighing and a three-target optimization method for optimizing rotor coaxiality, unbalance and rotational inertia and improving rotor assembly quality, and provides the following technical scheme:

an aircraft engine rotor assembly measuring device based on three-point weighing, the device comprising: the device comprises a base 1, an air flotation shafting 2, a weighing sensor 3, a leveling and inclination adjusting platform 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;

the air-floating shafting 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 cylinder 2f, a shifting fork 2g, a permanent magnet 2h, a coil 2i, a photoelectric counter 2j, a torsion bar 2k and a torsion bar locking device 2 l;

the weighing sensor 3 comprises a weighing sensor 3a, a weighing sensor 3b and a weighing sensor 3c, and the weighing sensor 3a, the weighing sensor 3b and the weighing sensor 3c are distributed in an isosceles triangle shape;

the air-floating upper plate 2a is arranged on the upper end part of an air-floating main shaft 2b, the air-floating lower plate 2c is arranged on the lower end part of the air-floating main shaft 2b, a circular grating ruler 2d is arranged on the outer wall of the side surface of the air-floating lower plate 2c, a circular grating reading head 2e is arranged on the inner wall of a base 1 and is transversely aligned with the circular grating ruler 2d, an air cylinder 2f is arranged on the inner wall of the base 1, a shifting fork 2g is arranged on the outer wall of the air-floating lower plate 2c, a permanent magnet 2h is arranged on the outer ring of the air-floating main shaft 2b, a coil 2i is arranged on the outer ring of the air-floating main shaft 2b and is longitudinally aligned with the permanent magnet 2h, a photoelectric counter 2j is arranged on the outer ring of the air-floating lower plate 2c, a torsion bar 2k is arranged on the central position of the air-, a leveling and inclination-adjusting platform 4 is arranged on a weighing sensor 3, the leveling and inclination-adjusting platform 4 is positioned on the central position of an air floating shaft system 2, a hydraulic chuck 5 is arranged on the central position of the leveling and inclination-adjusting platform 4, a left upright post transverse guide rail 6a and a right upright post transverse guide rail 6b are symmetrically distributed on two sides of the air floating shaft system 2 and are fixedly arranged on a base 1, a left upright post vertical guide rail 7a is arranged on the left upright post transverse guide rail 6a, a right upright post vertical guide rail 7b is arranged on the right upright post 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 upright post vertical guide rail 7a, a right lower transverse measuring rod 8c and a right upper transverse measuring rod 8d are horizontally nested on the right upright post vertical guide rail 7b, a left lower telescopic inductive sensor 9a is arranged at the end part of the left lower transverse measuring rod 8a, a left upper telescopic inductive sensor, the right upper lever type inductive sensor 9c is arranged at the end part of the right upper transverse measuring rod 8c, the right lower lever type inductive sensor 9d is arranged at the end part of the right lower transverse measuring rod 8d, and the measured rotor 10 is arranged on the hydraulic chuck 5.

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

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

step 1: aligning and adjusting the leveling and inclination adjusting platform 4, ensuring that the centroid of the assembly reference surface is concentric with the rotation axis of the leveling and inclination adjusting platform 4 shaft system, ensuring that the assembly reference surface is parallel to the leveling and inclination adjusting platform 4 plane, 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 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: optimizing three targets of coaxiality, unbalance and longitudinal axis moment of inertia of the multistage rotor to obtain an 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, the mass center offset and the rotational inertia of the assembly to ensure that the assembly requirement indexes are met.

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

step 1.1: a measured rotor 10 is placed on the leveling and inclination adjusting platform 4 and fixed through a hydraulic chuck 5, and a right lower lever type inductive sensor 9c and a right upper lever type inductive 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: the air flotation shafting 2 drives the measured rotor 10 to uniformly rotate at the speed of 6r/min to 10r/min through the leveling and inclination adjusting platform 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 the requirement of 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 leveling and inclination adjusting platform 4 according to the size and the angle of the eccentric amount, and adjusting the inclination adjusting knob of the leveling and inclination adjusting platform 4 according to the size and the angle of the inclination amount until the leveling and inclination adjusting platform 4 meets the condition that the size of the eccentric amount of the radial reference surface is in the range of 0 to 3 mu m and the size of the inclination 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 center of the air floatation shaft system 2 as a total reference, the weighing sensor 3a, the weighing sensor 3b and the weighing sensor 3c are distributed in an isosceles triangle and are arranged on the table surface of the air floatation upper plate 2 a;

step 3.2: the bearing point of the weighing sensor 3a is coincided with the X axis, and the distance from the origin of coordinates is L₁(ii) a The weighing sensor 3b and the weighing sensor 3c are symmetrically arranged at 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 a Y axis, and the distance between the bearing point of the weighing sensor 3b and the Y axis is L₃At a distance L from the X-axis₄(ii) a The distance between the bearing point of the weighing sensor 3c and the Y axis is L₂At a distance L from the X-axis₅；

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、F₂And F₃Difference values of no load and loading of the weighing sensor 3a, the weighing sensor 3b and the weighing sensor 3c are respectively, and Gx is an abscissa of the centroid of the measured rotor 10; gy is 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;

determining the moment of inertia of the longitudinal shaft of the ith-stage rotor after the multistage rotor is assembled, and expressing the moment of inertia of the longitudinal shaft of the ith-stage rotor after the multistage rotor is assembled by the following formula:

JH_i＝(ZH_i(x) ²+ZH_i(y) ²)M_i (7)

wherein JH_iThe moment of inertia of the longitudinal axis of the ith-stage rotor after the multistage rotor is assembled;

step 4.2: establishing an optimization target, wherein the optimization target is three targets, namely, the unbalance amount of the whole coaxiality and the moment of inertia of the longitudinal axis after the multi-stage rotor is assembled, the coaxiality is the maximum value of the concentricity of each single-stage rotor after the rotors are assembled, and the coaxiality is calculated by the following formula:

c＝max{CH_i,i＝1,2,...,n} (8)

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

the unbalance amount is the product of the total mass of the assembly body and the mass center offset, and the mass center offset and the unbalance amount are represented by the following formula:

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

the moment of inertia of the longitudinal axis, which is the product of the total mass of the fitting body and the square of the offset of the center of mass, is expressed by the following equation:

wherein J is the moment of inertia of the longitudinal axis;

step 4.3: establishing a tri-objective 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;for a single objective optimization function based on centroid offsets,a single objective optimization function based on the amount of unbalance is represented,representing a single objective optimization function based on the moment of inertia;

step 4.4: converting the three-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, c_△For the minimum value of the coaxiality-based single-objective optimization function, U_△For the minimum of a single-objective optimization function based on the amount of unbalance, J_△Is the minimum value of a single-target optimization function based on the moment of inertia;

step 4.5: obtaining the optimal transfer angle theta of each stage of rotor through a genetic algorithm_ziSo as to make the coaxiality, the unbalance amount and the rotational inertia close to the minimum value of each single target optimization, and achieve the aim of realizing the same assembly baseAnd the coaxiality, the unbalance amount and the rotational inertia of the rotor are optimized at the same time in a quasi-downward mode.

Preferably, the polarity of the longitudinal axis moment of inertia of the assembly is measured, and the idle period T of the bearing rotary table is measured₀Moment of inertia J of the turntable₀＝AT₀ ²Measuring common runout period Ts of a standard sample and a bearing rotary table, wherein the rotational inertia of the standard sample is Js, and obtaining a proportionality coefficientMeasuring the common-pendulum period T of the measured rotor and the bearing rotary table, and measuring the longitudinal axis moment of inertia J of the measured assembly body_c＝A(T²-T₀ ²)。

Preferably, a torsion bar 2k is locked through a torsion bar locking device 2l, and a cylinder 2f pushes a shifting fork 2g to drive an air floatation shaft system 2 to generate micro angular displacement; the air cylinder 2f is loosened, and the air floatation shaft system 2 generates periodic compound pendulum motion under the action of the elastic restoring force of the torsion bar 2 k; the photoelectric counter 2j records the runout period of the air floatation shaft system 2.

The invention has the following beneficial effects:

the existing aircraft engine rotor assembly optimization method only optimizes the overall coaxiality of the assembled multistage rotor so as to realize the optimized assembly of the assembled multistage rotor from the angle of geometric quantity without generating excessive bending of an assembly axis. The assembly optimization method comprehensively considers the geometric and mass characteristics of the multistage rotor, can realize multi-target synchronous optimization of the integral coaxiality, the unbalance amount and the rotational inertia of the assembled multistage rotor, can control the assembly axis not to generate transition bending, and can control the unbalance amount and the rotational inertia 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, centroid coordinates and rotational inertia of the measured rotor at the same time. 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 three-point weighing-based three-target optimization method for assembling an aircraft engine rotor;

FIG. 2 is a schematic view of an aircraft engine rotor assembly measuring device based on three-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.