阅读说明：本技术 火箭发动机三向力测量装置侧向力标定工装及标定方法 (Lateral force calibration tool and calibration method for rocket engine three-dimensional force measurement device ) 是由 唐斌运 陈雨 刘洋 郭玉凤 史雪梅 杨战伟 于 2020-06-22 设计创作，主要内容包括：本发明公开了一种火箭发动机三向力测量装置侧向力标定工装及标定方法。该标定工装包括左框架、右框架、动架模拟梁、固定梁、力加载油缸、加载力传感器以及8个标定传感器；将4个待标定柔性联接件安装在左框架和动架模拟梁左端之间,将4个待标定柔性联接件安装在右框架和动架模拟梁右端之间,通过力加载油缸向动架模拟梁施加推力,从而标定出8个待标定柔性联接件的刚性比,并对8个待标定柔性联接件同一刚性比相差最小的原则进行搭配并重新装于标定工装内,按照三遍六档加载原则获取左框架以及右框架处的刚性比。通过本发明避免了在三向力测量装置上直接进行标定所带来的标定周期长,能耗大,成本高的问题。(The invention discloses a lateral force calibration tool and a calibration method for a rocket engine three-directional force measurement device. The calibration tool comprises a left frame, a right frame, a movable frame simulation beam, a fixed beam, a force loading oil cylinder, a loading force sensor and 8 calibration sensors; the method comprises the steps of installing 4 flexible connecting parts to be calibrated between a left frame and the left end of a movable frame simulation beam, installing 4 flexible connecting parts to be calibrated between a right frame and the right end of the movable frame simulation beam, applying thrust to the movable frame simulation beam through a force loading oil cylinder, calibrating rigidity ratios of 8 flexible connecting parts to be calibrated, matching the 8 flexible connecting parts to be calibrated according to the principle that the same rigidity ratio is the smallest in difference, reinstalling the matched flexible connecting parts into a calibration tool, and obtaining rigidity ratios of the left frame and the right frame according to the three-time six-gear loading principle. The invention avoids the problems of long calibration period, high energy consumption and high cost caused by directly calibrating on the three-way force measuring device.)

1. The utility model provides a frock is markd to rocket engine three-dimensional force measuring device lateral force which characterized in that: the device comprises a left frame, a right frame, a movable frame simulation beam, a fixed beam, a force loading oil cylinder, a loading force sensor and 8 calibration sensors;

the left frame comprises two parallel supporting legs, a top beam fixedly connected between the supporting legs and positioned at the top, and a middle beam fixedly connected between the supporting legs and positioned in the middle; the two support legs, the top beam and the middle beam form a flexible connecting piece mounting area to be calibrated;

the right frame structure is completely the same as the left frame, and the left frame and the right frame are arranged in parallel;

a fixed beam is fixedly connected between the top beam of the left frame and the top beam of the right frame;

the force loading oil cylinder is fixedly connected to the middle part of the fixed beam, and the movable end of the force loading oil cylinder is connected with the middle part of the movable frame simulation beam;

the number of the flexible connecting pieces to be calibrated is 8, wherein 4 flexible connecting pieces to be calibrated are positioned in the mounting area of the flexible connecting pieces to be calibrated of the left frame, the 4 flexible connecting pieces to be calibrated are arranged in a cross shape, one end of each flexible connecting piece to be calibrated is connected with the left end of the movable frame simulation beam, and the other end of each flexible connecting piece to be calibrated is connected with the left frame;

the other 4 flexible connecting pieces to be calibrated are positioned in the mounting area of the flexible connecting pieces to be calibrated of the left frame, the 4 flexible connecting pieces to be calibrated are arranged in a cross shape, one end of each flexible connecting piece to be calibrated is connected with the right end of the movable frame simulation beam, and the other end of each flexible connecting piece to be calibrated is connected with the right frame;

and a loading force sensor is arranged at the force loading oil cylinder, and a calibration sensor is arranged on each flexible connecting piece to be calibrated.

2. The rocket engine three-way force measuring device lateral force calibration tool of claim 1, characterized in that: the tool further comprises a fine screw rod arranged between each flexible connecting piece to be calibrated and the movable frame simulation beam; one end of the thin screw rod is in threaded connection with the flexible connecting piece to be calibrated, and the other end of the thin screw rod is in threaded connection with the movable frame simulation beam.

3. A method for calibrating lateral force of a rocket engine three-direction force measuring device is characterized by comprising the following steps: the calibration tool of claim 1 is adopted, and the specific calibration steps are as follows:

step 1: establishing a tool coordinate system XYZ and a flexible connecting piece coordinate system XYZ;

the direction of the thrust loaded by the force loading oil cylinder is the X direction in the tool coordinate system XYZ; the Z direction is the axial direction of the movable frame simulation beam, and the Y direction is the direction which is simultaneously vertical to the X direction and the Y direction;

the middle z direction of a flexible connecting piece coordinate system xyz is the direction of the central axis of the flexible connecting piece coordinate system xyz, the x direction is the opening direction of the notch in the notch group I, and the y direction is the opening direction of the notch in the notch group II;

step 2: numbering flexible connecting pieces to be calibrated;

marking 8 flexible connecting pieces to be calibrated as No. 1, No. 2, No. 3, No. 4, No. 5, No. 6, No. 7 and No. 8 respectively;

and step 3: calibrating for the first time;

step 3.1: installing No. 1-No. 4 flexible connecting pieces to be calibrated in a flexible connecting piece installation area of a left frame to be calibrated in a cross distribution mode, wherein the No. 1 and No. 2 flexible connecting pieces to be calibrated are arranged along the X direction of a tool coordinate system, and the No. 3 and No. 4 flexible connecting pieces to be calibrated are installed along the Y direction of the tool coordinate system;

installing No. 5-No. 8 flexible connecting pieces to be calibrated in the installation area of the flexible connecting pieces to be calibrated of the right frame in a cross distribution mode; the number 5 and number 6 flexible connecting pieces to be calibrated are installed along the X direction of the tool coordinate system, and the number 7 and number 8 flexible connecting pieces to be calibrated are installed along the Y direction of the tool coordinate system;

step 3.2: starting to load thrust to the moving frame simulation beam by using a force loading oil cylinder, and directly obtaining actual loading force by using a force loading sensor;

at the moment, the calibration sensors at the flexible connecting piece to be calibrated can acquire the signals through No. 1, No. 2, No. 5 and No. 6The stress of the flexible connecting piece to be calibrated No. 1, No. 2, No. 5 and No. 6 along the z direction of the coordinate system of the flexible connecting piece is respectively marked as F_1-1z、F_2-1z、F_5-1z、F_6-1z；

Step 3.3: changing the installation positions of No. 1 and No. 2 flexible connecting pieces to be calibrated, changing the installation positions of No. 5 and No. 6 flexible connecting pieces to be calibrated, and then starting the force loading oil cylinder to load the same thrust to the moving frame simulation beam again to obtain the stress sizes of No. 1, No. 2, No. 5 and No. 6 flexible connecting pieces to be calibrated along the z direction of the coordinate system of the flexible connecting pieces, which are respectively marked as F_1-2z、F_2-2z、F_5-2z、F_6-2z；

Step 3.4: solving the actual stress of the flexible coupling parts to be calibrated No. 1, No. 2, No. 5 and No. 6 along the z direction of the coordinate system after the influence of gravity is eliminated, wherein the specific calculation formula is as follows:

step 3.5: the stress of the flexible connecting piece to be calibrated No. 3, No. 4, No. 7 and No. 8 along the y direction of the coordinate system of the flexible connecting piece can be obtained through the calibration sensors at the flexible connecting piece to be calibrated No. 3, No. 4, No. 7 and No. 8, and is respectively marked as F_3-y、F_4-y、F_7-y、F_8-y；

F is to be_3-y、F_4-yPerforming comparison and verification, if F_3-y、F_4-yRecording if the sizes are the same or similar, otherwise checking No. 3 and No. 4 flexible couplings to be calibratedThe condition of connector assembly;

f is to be_7-y、F_8-yPerforming comparison and verification, if F_7-y、F_8-yRecording if the sizes are the same or similar, otherwise, checking the assembly conditions of No. 7 and No. 8 flexible connecting parts to be calibrated;

step 3.6: under the condition that the magnitude of the loading force is not changed, the flexible connecting pieces to be calibrated No. 3, No. 4, No. 7 and No. 8 rotate 90 degrees around the self axial direction, the stress of the flexible connecting pieces to be calibrated No. 3, No. 4, No. 7 and No. 8 along the x direction of the coordinate system of the flexible connecting pieces is obtained again and is respectively marked as F_3-x、F_4-x、F_7-x、F_8-x；

F is to be_3-x、F_4-xPerforming comparison and verification, if F_3-x、F_4-xRecording if the sizes are the same or similar, otherwise, checking the assembly conditions of No. 3 and No. 4 flexible connecting parts to be calibrated;

f is to be_7-x、F_8-xPerforming comparison and verification, if F_7-x、F_8-xRecording if the sizes are the same or similar, otherwise, checking the assembly conditions of No. 7 and No. 8 flexible connecting parts to be calibrated;

and 4, step 4: calibrating for the second time;

step 4.1; exchanging the installation positions of the No. 1 and No. 2 flexible connecting pieces to be calibrated and the No. 3 and No. 4 flexible connecting pieces to be calibrated; exchanging the installation positions of the No. 5 and No. 6 flexible connecting pieces to be calibrated and the No. 7 and No. 8 flexible connecting pieces to be calibrated;

step 4.2: obtaining the actual stress of the flexible coupling parts to be calibrated No. 3, No. 4, No. 7 and No. 8 along the z direction of the coordinate system of the flexible coupling parts in the same way as the steps 3.2 to 3.6, and marking the actual stress as F_3-z、F_4-z、F_7-z、F_8-zAnd the actual stress of the flexible connecting piece to be calibrated No. 1, No. 2, No. 5 and No. 6 along the y direction and the x direction of the coordinate system of the flexible connecting piece is marked as F_1-y、F_2-y、F_5-y、F_6-y、F_1-x、F_2-x、F_5-x、F_6-x；

And 5: obtaining the rigidity ratio of 8 flexible coupling parts to be calibrated, which is marked as W, according to the calibration results of the step 3 and the step 4_i(x/y)，W_i(x/z) and W_i(y/z), wherein i is the designation of the flexible coupling to be calibrated;

step 6: comparing the rigidity ratios of the 8 flexible connecting pieces to be calibrated, and matching according to the principle that the difference between the same rigidity ratio of every two flexible connecting pieces to be calibrated is minimum, so that the 8 flexible connecting pieces are installed in the calibration tool again;

and 7: the static force is loaded in a grading mode through the force loading oil cylinder, according to the rated loading force, the static force is loaded in a six-gear loading principle for three times, the numerical value of a calibration sensor at each flexible connecting piece is read, and the rigidity ratio of the left frame to be calibrated after the four flexible connecting pieces to be calibrated are installed on the left frame in the calibration tool and the rigidity ratio of the right frame to be calibrated after the four flexible connecting pieces to be calibrated are installed on the right frame under the conditions of different loading forces are calculated respectively.

4. A rocket engine three-way force measuring device lateral force calibration method according to claim 3, characterized in that: the calculation formulas of the rigidity ratio of the left frame after the four flexible connecting parts to be calibrated are arranged and the rigidity ratio of the right frame after the four flexible connecting parts to be calibrated are as follows:

W_{left side of}＝＝(F₁+F₂)/(F₃+F₄)

W_{Right side}＝＝(F₅+F₆)/(F₇+F₈)。

Wherein, W_{Left side of}Is the stiffness ratio at the left frame; w_{Right side}Is the stiffness ratio at the right frame;

F₁to F₈And reading the corresponding calibration sensor of each flexible coupling to be calibrated after calibration.

5. A rocket engine three-way force measuring device lateral force calibration method according to claim 3, characterized in that: in the three-pass six-gear loading principle: the three times represent the loading times of each actually output loading force; the sixth gear represents the actual output loading force in different proportions based on the nominal loading force.

Technical Field

The invention relates to the field of high-thrust rocket engine tests, in particular to a lateral force calibration tool and a calibration method for a rocket engine three-directional force measurement device.

Background

Chinese patent, application number is: 2018109953203, discloses a three-way force measuring device and method for a high thrust rocket engine, the main objective of the invention is to finish the thrust measurement in the axial direction, the tangential direction and the radial direction in the engine test process, because the thrust measurement research mainly aims at the test of the new generation liquid oxygen kerosene engine, the test system adopts a movable frame structure and a fixed frame structure, and a plurality of flexible connectors are directly adopted between the movable frame and the fixed frame for connection. The measurement model is shown in the following fig. 1 and 2, and the three-way force measuring device comprises an axial force measuring unit 01, a lower layer lateral thrust measuring unit 02 and an upper layer lateral thrust measuring unit 03.

The three-way force measuring device mainly solves the problem of mutual interference in all directions, an ideal elastic restraint original piece is represented as a rigid body in the self force bearing direction, and a non-force bearing direction is represented as a flexible connecting piece. As shown in FIG. 3, the flexible connector is cylindrical, the axis direction of the flexible connector is defined as a Z axis, a notch group I and a notch group II are arranged on the flexible connector, and the notch group I and the notch group II are sequentially arranged along the Z axis; the notch group I comprises two first notches, the two first notches face to the positive direction and the negative direction of the X axis respectively, and the two first notches are symmetrically arranged around the Z axis; the notch group ii includes two second notches which face positive and negative directions of the Y axis, respectively, and the two second notches are symmetrically arranged about the Z axis, and the actual flexible coupling member has extremely high rigidity ratios, but cannot have ideal characteristics, so it becomes very important to calibrate the rigidity of the flexible coupling member in each direction of the core thereof, and to combine a plurality of flexible coupling members in an optimal manner, and to find out the system combination rigidity ratio and the characteristics under low frequency dynamics in such a combination before use, so as to provide effective correction data for later data analysis.

The system for the test is huge, if the three-way force measuring device is calibrated on line, the three-way force measuring device needs to be calibrated under the condition that the engine is ignited to generate thrust, but because the measuring movable frame is large in mass and complex in structure, if the three-way force measuring device is calibrated for lateral force (namely X, Y direction shown in fig. 2) in the engine test process, the calibration period is long, the energy consumption is high, and the cost is high. Therefore, it is urgently needed to provide a simple and accurate calibration method for calibrating the lateral force of the three-way force measuring device.

Disclosure of Invention

The invention provides a lateral force calibration tool and a lateral force calibration method for a rocket engine three-way force measuring device, and aims to solve the problems of long calibration period, high energy consumption and high cost when the existing three-way force measuring device carries out online lateral force calibration.

The specific technical scheme of the invention is as follows:

the invention provides a lateral force calibration tool of a rocket engine three-dimensional force measuring device, which comprises a left frame, a right frame, a movable frame simulation beam, a fixed beam, a force loading oil cylinder, a loading force sensor and 8 calibration sensors 7, wherein the left frame is provided with a left frame;

the left frame comprises two parallel supporting legs, a top beam fixedly connected between the supporting legs and positioned at the top, and a middle beam fixedly connected between the supporting legs and positioned in the middle; the two support legs, the top beam and the middle beam form a flexible connecting piece mounting area to be calibrated;

the right frame structure is completely the same as the left frame, and the left frame and the right frame are arranged in parallel;

a fixed beam is fixedly connected between the top beam of the left frame and the top beam of the right frame;

the force loading oil cylinder is fixedly connected to the middle part of the fixed beam, and the movable end of the force loading oil cylinder is connected with the middle part of the movable frame simulation beam;

the number of the flexible connecting pieces to be calibrated is 8, wherein 4 flexible connecting pieces to be calibrated are positioned in the mounting area of the flexible connecting pieces to be calibrated of the left frame, the 4 flexible connecting pieces to be calibrated are arranged in a cross shape, one end of each flexible connecting piece to be calibrated is connected with the left end of the movable frame simulation beam, and the other end of each flexible connecting piece to be calibrated is connected with the left frame;

the other 4 flexible connecting pieces to be calibrated are positioned in the mounting area of the flexible connecting pieces to be calibrated of the left frame, the 4 flexible connecting pieces to be calibrated are arranged in a cross shape, one end of each flexible connecting piece to be calibrated is connected with the right end of the movable frame simulation beam, and the other end of each flexible connecting piece to be calibrated is connected with the right frame;

and a loading force sensor is arranged at the force loading oil cylinder, and a calibration sensor is arranged on each flexible connecting piece to be calibrated.

Further, the tool further comprises a fine screw rod arranged between each flexible connecting piece to be calibrated and the movable frame simulation beam; one end of the thin screw rod is in threaded connection with the flexible connecting piece to be calibrated, and the other end of the thin screw rod is in threaded connection with the movable frame simulation beam.

Based on the structural description of the calibration tool, a method for calibrating the lateral force of the three-way force measuring device by using the tool is introduced:

step 1: establishing a tool coordinate system XYZ and a flexible connecting piece coordinate system XYZ;

the direction of the thrust loaded by the force loading oil cylinder is the X direction in the tool coordinate system XYZ; the Z direction is the axial direction of the movable frame simulation beam, and the Y direction is the direction which is simultaneously vertical to the X direction and the Y direction;

the middle z direction of a flexible connecting piece coordinate system xyz is the direction of the central axis of the flexible connecting piece coordinate system xyz, the x direction is the opening direction of the notch in the notch group I, and the y direction is the opening direction of the notch in the notch group II;

step 2: numbering flexible connecting pieces to be calibrated;

marking 8 flexible connecting pieces to be calibrated as No. 1, No. 2, No. 3, No. 4, No. 5, No. 6, No. 7 and No. 8 respectively;

and step 3: calibrating for the first time;

step 3.1: installing No. 1-No. 4 flexible connecting pieces to be calibrated in a flexible connecting piece installation area of a left frame to be calibrated in a cross distribution mode, wherein the No. 1 and No. 2 flexible connecting pieces to be calibrated are arranged along the X direction of a tool coordinate system, and the No. 3 and No. 4 flexible connecting pieces to be calibrated are installed along the Y direction of the tool coordinate system;

installing No. 5-No. 8 flexible connecting pieces to be calibrated in the installation area of the flexible connecting pieces to be calibrated of the right frame in a cross distribution mode; the number 5 and number 6 flexible connecting pieces to be calibrated are installed along the X direction of the tool coordinate system, and the number 7 and number 8 flexible connecting pieces to be calibrated are installed along the Y direction of the tool coordinate system;

step 3.2: starting to load thrust to the moving frame simulation beam by using a force loading oil cylinder, and directly obtaining actual loading force by using a force loading sensor;

at the moment, the stress of the flexible coupling parts to be calibrated No. 1, No. 2, No. 5 and No. 6 along the z direction of the coordinate system of the flexible coupling parts can be obtained through the calibration sensors at the flexible coupling parts to be calibrated No. 1, No. 2, No. 5 and No. 6, which are respectively marked as F_1-1z、F_2-1z、F_5-1z、F_6-1z；

Step 3.3: changing the installation positions of No. 1 and No. 2 flexible connecting pieces to be calibrated, changing the installation positions of No. 5 and No. 6 flexible connecting pieces to be calibrated, and then starting the force loading oil cylinder to load the same thrust to the moving frame simulation beam again to obtain the stress sizes of No. 1, No. 2, No. 5 and No. 6 flexible connecting pieces to be calibrated along the z direction of the coordinate system of the flexible connecting pieces, which are respectively marked as F_1-2z、F_2-2z、F_5-2z、F_6-2z；

Step 3.4: solving the actual stress of the flexible coupling parts to be calibrated No. 1, No. 2, No. 5 and No. 6 along the z direction of the coordinate system after the influence of gravity is eliminated, wherein the specific calculation formula is as follows:

step 3.5: through the calibration of No. 3, No. 4, No. 7 and No. 8 flexible connecting parts to be calibratedThe sensor can acquire the stress of the No. 3, No. 4, No. 7 and No. 8 flexible connectors to be calibrated along the y direction of the coordinate system of the flexible connectors, and the stress is respectively marked as F_3-y、F_4-y、F_7-y、F_8-y；

F is to be_3-y、F_4-yPerforming comparison and verification, if F_3-y、F_4-yRecording if the sizes are the same or similar, otherwise, checking the assembly conditions of No. 3 and No. 4 flexible connecting parts to be calibrated;

f is to be_7-y、F_8-yPerforming comparison and verification, if F_7-y、F_8-yRecording if the sizes are the same or similar, otherwise, checking the assembly conditions of No. 7 and No. 8 flexible connecting parts to be calibrated;

step 3.6: under the condition that the magnitude of the loading force is not changed, the flexible connecting pieces to be calibrated No. 3, No. 4, No. 7 and No. 8 rotate 90 degrees around the self axial direction, the stress of the flexible connecting pieces to be calibrated No. 3, No. 4, No. 7 and No. 8 along the x direction of the coordinate system of the flexible connecting pieces is obtained again and is respectively marked as F_3-x、F_4-x、F_7-x、F_8-x；

F is to be_3-x、F_4-xPerforming comparison and verification, if F_3-x、F_4-xRecording if the sizes are the same or similar, otherwise, checking the assembly conditions of No. 3 and No. 4 flexible connecting parts to be calibrated;

f is to be_7-x、F_8-xPerforming comparison and verification, if F_7-x、F_8-xRecording the same or similar sizes, otherwise checking the assembling conditions of No. 7 and No. 8 flexible connecting parts to be calibrated, and adjusting the mounting postures of the two flexible connecting parts to be calibrated to ensure that F_7-x、F_8-xThe sizes are the same or similar;

and 4, step 4: calibrating for the second time;

step 4.1; exchanging the installation positions of the No. 1 and No. 2 flexible connecting pieces to be calibrated and the No. 3 and No. 4 flexible connecting pieces to be calibrated; exchanging the installation positions of the No. 5 and No. 6 flexible connecting pieces to be calibrated and the No. 7 and No. 8 flexible connecting pieces to be calibrated;

step 4.2: obtaining No. 3, No. 4, No. 7 and No. 8 flexible connecting pieces to be calibrated along the coordinate system of the flexible connecting pieces in the same way as the steps 3.2 to 3.6The actual force in the z-direction is denoted as F_3-z、F_4-z、F_7-z、F_8-zAnd the actual stress of the flexible connecting piece to be calibrated No. 1, No. 2, No. 5 and No. 6 along the y direction and the x direction of the coordinate system of the flexible connecting piece is marked as F_1-y、F_2-y、F_5-y、F_6-y、F_1-x、F_2-x、F_5-x、F_6-x；

And 5: obtaining the rigidity ratio of 8 flexible coupling parts to be calibrated, which is marked as W, according to the calibration results of the step 3 and the step 4_i(x/y)，W_i(x/z) and W_i(y/z), wherein i is the designation of the flexible coupling to be calibrated;

step 6: comparing the rigidity ratios of the 8 flexible connecting pieces to be calibrated, and matching according to the principle that the difference between the same rigidity ratio of every two flexible connecting pieces to be calibrated is minimum, so that the 8 flexible connecting pieces are installed in the calibration tool again;

and 7: the static force is loaded in a grading mode through the force loading oil cylinder, according to the rated loading force, the static force is loaded in a six-gear loading principle for three times, the numerical value of a calibration sensor at each flexible connecting piece is read, and the rigidity ratio of the left frame to be calibrated after the four flexible connecting pieces to be calibrated are installed on the left frame in the calibration tool and the rigidity ratio of the right frame to be calibrated after the four flexible connecting pieces to be calibrated are installed on the right frame under the conditions of different loading forces are calculated respectively.

Further, the calculation formula of the rigidity ratio of the left frame to which the four flexible connectors to be calibrated are mounted and the calculation formula of the rigidity ratio of the right frame to which the four flexible connectors to be calibrated are mounted is as follows:

W_{left side of}＝＝(F₁+F₂)/(F₃+F₄)

W_{Right side}＝＝(F₅+F₆)/(F₇+F₈)

Wherein, W_{Left side of}Is the stiffness ratio at the left frame; w_{Right side}Is the stiffness ratio at the right frame;

F₁to F₈And reading the corresponding calibration sensor of each flexible coupling to be calibrated after calibration.

Further, in the three-pass six-gear loading principle: the three times represent the loading times of each actually output loading force; the sixth gear represents the actual output loading force in different proportions based on the nominal loading force.

The invention has the beneficial effects that:

1. the invention adopts the left frame, the right frame, the movable frame simulation beam, the fixed beam, the force loading oil cylinder, the loading force sensor and 8 calibration sensors to construct a tool for calibrating the lateral force of the rocket engine three-way force measuring device, thereby avoiding the problems of long calibration period, large energy consumption and high cost caused by directly calibrating on the three-way force measuring device.

2. According to the invention, based on the principle of consistency of transmission of the tool and the actually used force, rigidity ratio calculation in each direction is respectively carried out on 8 flexible connecting pieces, and by optimizing the matching combination mode of the flexible connecting pieces, the deviation of all directions consistency is reduced, so that powerful support is provided for improving the precision of three-component force measurement.

Drawings

FIG. 1 is a schematic diagram of a three-way force measuring device of a rocket engine;

FIG. 2 is a top view of FIG. 1;

FIG. 3 is a block diagram of a flex link;

fig. 4 is a structural diagram of the calibration tool.

The reference numbers are as follows:

1-left frame, 11-supporting leg, 12-top beam, 13-middle beam, 2-right frame, 3-moving frame simulation beam, 4-fixed beam, 5-force loading oil cylinder, 6-loading force sensor, 7-calibration sensor and 8-flexible connecting piece to be calibrated.

Detailed Description

In order to make the objects, advantages and features of the present invention clearer, the following provides a calibration tool and a calibration method for lateral force of a rocket engine three-way force measuring device, which are provided by the present invention, with reference to the accompanying drawings and specific embodiments. The advantages and features of the present invention will become more apparent from the following description. It should be noted that: the drawings are in simplified form and are not to precise scale, the intention being solely for the convenience and clarity of illustrating embodiments of the invention; second, the structures shown in the drawings are often part of actual structures.

As shown in fig. 4, the embodiment provides a specific structure of a lateral force calibration tool of a rocket engine three-way force measuring device: the device comprises a left frame 1, a right frame 2, a movable frame simulation beam 3, a fixed beam 4, a force loading oil cylinder 5, a loading force sensor 6 and 8 calibration sensors 7;

the left frame 1 comprises two parallel supporting legs 11, a top beam 12 fixedly connected between the supporting legs 11 and positioned at the top, and a middle beam 13 fixedly connected between the supporting legs 11 and positioned at the middle; the two support legs 11, the top beam 12 and the middle beam 13 form a flexible connecting element mounting area to be calibrated;

the structure of the right frame 2 is completely the same as that of the left frame, and the left frame 1 and the right frame 2 are arranged in parallel;

a fixed beam 4 is fixedly connected between the top beam of the left frame 1 and the top beam of the right frame 2;

the force loading oil cylinder 5 is fixedly connected to the middle part of the fixed beam 4, and the movable end of the force loading oil cylinder 5 is connected with the middle part of the movable frame simulation beam 3;

the number of the flexible connecting parts 8 to be calibrated is 8, wherein 4 flexible connecting parts 8 to be calibrated (namely, the flexible connecting parts 1-4 to be calibrated in the figure) are positioned in the mounting area of the flexible connecting parts to be calibrated of the left frame 1, the 4 flexible connecting parts 8 to be calibrated are arranged in a cross shape, one end of each flexible connecting part 8 to be calibrated is connected with the left end of the movable frame simulation beam 3, and the other end of each flexible connecting part 8 to be calibrated is connected with the left frame 1;

the other 4 flexible connecting pieces 8 to be calibrated (namely, the flexible connecting pieces to be calibrated from No. 5 to No. 8 in the figure) are positioned in the mounting area of the flexible connecting pieces to be calibrated of the right frame 2, the 4 flexible connecting pieces to be calibrated are arranged in a cross shape, one end of each flexible connecting piece 8 to be calibrated is connected with the right end of the movable frame simulation beam 3, and the other end of each flexible connecting piece 8 to be calibrated is connected with the right frame 2;

it should be noted that: the loading force applied by the force loading oil cylinder 5 is equivalent to the lateral force brought by an engine borne by the three-way force measuring device;

in the embodiment, a structure formed by the left frame, the 4 flexible connecting pieces to be calibrated (namely, the flexible connecting pieces to be calibrated from No. 1 to No. 4 in the figure) and the left side of the movable frame simulation beam can equivalently simulate an upper layer lateral thrust measuring unit of an actual three-way force measuring device; the structure formed by the right frame, the 4 flexible connecting pieces to be calibrated (namely the flexible connecting pieces to be calibrated from No. 5 to No. 8 in the figure) and the right side of the movable frame simulation beam can equivalently simulate a lower lateral thrust measuring unit of an actual three-way force measuring device, and vice versa;

in the embodiment, each flexible connecting element 8 to be calibrated is connected with the movable frame simulation beam 3, the left frame 1 or the right frame 2 through a thin screw rod.

And a loading force sensor 6 is arranged at the force loading oil cylinder 5, and a calibration sensor 7 is arranged on each flexible connecting piece 8 to be calibrated.

The following details are given to a specific calibration method using the calibration tool according to the principle that the structure formed by the force loading cylinder output thrust equivalent to the lateral force provided by the engine and received by the actual process three-way force measuring device, the left frame, the 4 to-be-calibrated flexible coupling members (i.e. the to-be-calibrated flexible coupling members No. 1-4 in the figure) and the left side of the movable frame simulation beam can equivalently simulate the upper lateral thrust measuring unit and the right frame of the actual three-way force measuring device, the 4 to-be-calibrated flexible coupling members (i.e. the to-be-calibrated flexible coupling members No. 5-8 in the figure) and the structure formed by the right side of the movable frame simulation beam can equivalently simulate the lower lateral thrust measuring unit of the actual three-way force measuring device:

step 1: establishing a tool coordinate system XYZ and a flexible connecting piece coordinate system XYZ;

the X direction in the tooling coordinate system XYZ is the direction of the thrust loaded by the force loading cylinder (namely the direction of the lateral force to be simulated); the Z direction is the axial direction of the moving frame simulation beam (the direction from the left frame to the right frame in fig. 1), and the Y direction is the direction perpendicular to both the X direction and the Y direction;

as shown in fig. 3, the middle z direction of the flexible coupling coordinate system xyz is the direction of the central axis of the flexible coupling coordinate system, the x direction is the opening direction of the notches in the notch group i, and the y direction is the opening direction of the notches in the notch group ii;

step 2: numbering flexible connecting pieces to be calibrated;

marking 8 flexible connecting pieces to be calibrated as No. 1, No. 2, No. 3, No. 4, No. 5, No. 6, No. 7 and No. 8 respectively;

and step 3: calibrating for the first time;

step 3.1: installing No. 1-No. 4 flexible connecting pieces to be calibrated in a flexible connecting piece installation area of a left frame to be calibrated in a cross distribution mode, wherein the No. 1 and No. 2 flexible connecting pieces to be calibrated are arranged along the X direction of a tool coordinate system, and the No. 3 and No. 4 flexible connecting pieces to be calibrated are installed along the Y direction of the tool coordinate system;

installing No. 5-No. 8 flexible connecting pieces to be calibrated in the installation area of the flexible connecting pieces to be calibrated of the right frame in a cross distribution mode; the number 5 and number 6 flexible connecting pieces to be calibrated are installed along the X direction of the tool coordinate system, and the number 7 and number 8 flexible connecting pieces to be calibrated are installed along the Y direction of the tool coordinate system;

step 3.2: starting to load thrust to the moving frame simulation beam by using a force loading oil cylinder, and directly obtaining actual loading force by using a force loading sensor;

at the moment, the stress of the flexible coupling parts to be calibrated No. 1, No. 2, No. 5 and No. 6 along the z direction of the coordinate system of the flexible coupling parts can be obtained through the calibration sensors at the flexible coupling parts to be calibrated No. 1, No. 2, No. 5 and No. 6, which are respectively marked as F_1-1z、F_2-1z、F_5-1z、F_6-1z；

Step 3.3: changing the installation positions of No. 1 and No. 2 flexible connecting pieces to be calibrated, changing the installation positions of No. 5 and No. 6 flexible connecting pieces to be calibrated, and then starting the force loading oil cylinder to load the same thrust to the moving frame simulation beam again to obtain the stress sizes of No. 1, No. 2, No. 5 and No. 6 flexible connecting pieces to be calibrated along the z direction of the coordinate system of the flexible connecting pieces, which are respectively marked as F_1-2z、F_2-2z、F_5-2z、F_6-2z；

Step 3.4: solving the actual stress of the flexible coupling parts to be calibrated No. 1, No. 2, No. 5 and No. 6 along the z direction of the coordinate system after the influence of gravity is eliminated, wherein the specific calculation formula is as follows:

step 3.5: the stress of the flexible connecting piece to be calibrated No. 3, No. 4, No. 7 and No. 8 along the y direction of the coordinate system of the flexible connecting piece can be obtained through the calibration sensors at the flexible connecting piece to be calibrated No. 3, No. 4, No. 7 and No. 8, and is respectively marked as F_3-y、F_4-y、F_7-y、F_8-y；

F is to be_3-y、F_4-yPerforming comparison and verification, if F_3-y、F_4-yRecording the same or similar sizes, otherwise checking the assembly conditions of No. 3 and No. 4 flexible connecting parts to be calibrated, and adjusting the installation postures of the two flexible connecting parts to be calibrated to ensure that F_3-y、F_4-yThe sizes are the same or similar;

f is to be_7-y、F_8-yPerforming comparison and verification, if F_7-y、F_8-yRecording the same or similar sizes, otherwise checking the assembling conditions of No. 7 and No. 8 flexible connecting parts to be calibrated, and adjusting the mounting postures of the two flexible connecting parts to be calibrated to ensure that F_7-y、F_8-yThe sizes are the same or similar;

step 3.6: under the condition that the magnitude of the loading force is not changed, the flexible connecting pieces to be calibrated No. 3, No. 4, No. 7 and No. 8 rotate 90 degrees around the self axial direction, the stress of the flexible connecting pieces to be calibrated No. 3, No. 4, No. 7 and No. 8 along the x direction of the coordinate system of the flexible connecting pieces is obtained again and is respectively marked as F_3-x、F_4-x、F_7-x、F_8-x；

F is to be_3-x、F_4-xPerforming comparison and verification, if F_3-x、F_4-xRecording the same or similar sizes, otherwise checking the assembly conditions of No. 3 and No. 4 flexible connecting parts to be calibrated, and adjusting the installation postures of the two flexible connecting parts to be calibrated to ensure that F_3-x、F_4-xThe sizes are the same or similar;

f is to be_7-x、F_8-xPerforming comparison and verification, if F_7-x、F_8-xRecording the same or similar sizes, otherwise checking the assembling conditions of No. 7 and No. 8 flexible connecting parts to be calibrated, and adjusting the mounting postures of the two flexible connecting parts to be calibrated to ensure that F_7-x、F_8-xThe sizes are the same or similar;

and 4, step 4: calibrating for the second time;

step 4.1; exchanging the installation positions of the No. 1 and No. 2 flexible connecting pieces to be calibrated and the No. 3 and No. 4 flexible connecting pieces to be calibrated; exchanging the installation positions of the No. 5 and No. 6 flexible connecting pieces to be calibrated and the No. 7 and No. 8 flexible connecting pieces to be calibrated;

step 4.2: obtaining the actual stress of the flexible coupling parts to be calibrated No. 3, No. 4, No. 7 and No. 8 along the z direction of the coordinate system of the flexible coupling parts in the same way as the steps 3.2 to 3.6, and marking the actual stress as F_3-z、F_4-z、F_7-z、F_8-zAnd the actual stress of the flexible connecting piece to be calibrated No. 1, No. 2, No. 5 and No. 6 along the y direction and the x direction of the coordinate system of the flexible connecting piece is marked as F_1-y、F_2-y、F_5-y、F_6-y、F_1-x、F_2-x、F_5-x、F_6-x；

And 5: obtaining the rigidity ratio of 8 flexible coupling parts to be calibrated, which is marked as W, according to the calibration results of the step 3 and the step 4_i(x/y)，W_i(x/z) and W_i(y/z), wherein i is the designation of the flexible coupling to be calibrated;

step 6: comparing the rigidity ratios of the 8 flexible connecting pieces to be calibrated, and matching according to the principle that the difference between the same rigidity ratio of every two flexible connecting pieces to be calibrated is minimum, so that the 8 flexible connecting pieces are installed in the calibration tool again;

for example: the rigidity ratio of the No. 1 flexible connecting piece to be calibrated and the No. 8 flexible connecting piece to be calibrated has the smallest difference, the rigidity ratio of the No. 2 flexible connecting piece to be calibrated and the No. 6 flexible connecting piece have the smallest difference, the rigidity ratio of the No. 3 flexible connecting piece to the No. 5 flexible connecting piece to be calibrated and the No. 4 flexible connecting piece to be calibrated and the No. 6 flexible connecting piece to be calibrated have the smallest difference, the rigidity ratio of the No. 3 flexible connecting piece to the No. 5 flexible connecting piece to be calibrated and the rigidity ratio of the No. 4 flexible connecting piece to be calibrated and the rigidity ratio of the No; installing No. 3, No. 5, No. 4 and No. 7 on a right frame, arranging No. 3 and No. 5 along the X direction of a tooling coordinate system, and installing No. 4 and No. 7 flexible connecting pieces to be calibrated along the Y direction of the tooling coordinate system;

and 7: the static force is loaded in a stepping mode through the force loading oil cylinder, the static force is loaded according to the rated loading force and then according to a three-pass six-gear loading principle (three passes in the three-pass six-gear loading principle represent the loading times of each actually output loading force, six passes represent the loading forces which are actually output according to different proportions on the basis of the rated loading force, and the six different proportions are respectively 10%, 20%, 40%, 60%, 80% and 100% in the embodiment), by reading the value of the calibration sensor at each flexible connector, respectively calculating the rigidity ratio of the left frame in the calibration tool after four flexible connectors to be calibrated are arranged, and the rigidity ratio of the right frame under different loading force conditions after four flexible connecting parts to be calibrated are arranged on the right frame, therefore, the calibration result of the upper layer lateral thrust measurement unit and the calibration result of the lower layer lateral thrust measurement unit are equivalently obtained.

Specifically, the calculation formulas of the rigidity ratio (calibration result of the upper layer lateral thrust measuring unit) after the four flexible coupling parts to be calibrated are arranged on the left frame and the rigidity ratio (lower layer lateral thrust measuring unit) after the four flexible coupling parts to be calibrated are arranged on the right frame are as follows:

W_{left side of}＝＝(F₁+F₂)/(F₃+F₄)

W_{Right side}＝＝(F₅+F₆)/(F₇+F₈)。

Wherein, W_{Left side of}Is the stiffness ratio at the left frame; w_{Right side}Is the stiffness ratio at the right frame;

F₁to F₈For each after calibrationAnd calibrating the reading of the corresponding calibration sensor of the flexible coupling.