阅读说明：本技术 内螺纹磨削过程的磨削力测量方法 (Grinding force measuring method in internal thread grinding process ) 是由 姜佳利 张春雷 张辉 伍梓聪 叶佩青 赵彤 于 2020-04-02 设计创作，主要内容包括：本发明公开了一种内螺纹磨削过程的磨削力测量方法,步骤包括安装待测工件、检测待测工件径向跳动量和磨削力测量,将待测工件固定在固定式测力计上,将固定式测力计安装在机床的头架卡盘上,并确保待测工件的轴线、固定式测力计的轴线以及头架卡盘的轴线在水平方向上重合,将固定式测力计与数据系统电连接；检测待测工件的径向跳动量,确保径向跳动量不大于0.002mm；固定式测力计测得头架带料空转时和内螺纹磨削时的原始数据,并将原始数据输送给数据系统,数据系统对原始数据进行处理,最终得到磨削力大小。本发明的内螺纹磨削过程的磨削力测量方法能够方便地对内螺纹磨削过程的磨削力进行测量,测量结果准确可靠,结构简单且装配方便。(The invention discloses a grinding force measuring method in the process of grinding internal threads, which comprises the steps of installing a workpiece to be measured, detecting the radial runout amount and the grinding force measurement of the workpiece to be measured, fixing the workpiece to be measured on a fixed dynamometer, installing the fixed dynamometer on a headstock chuck of a machine tool, ensuring that the axis of the workpiece to be measured, the axis of the fixed dynamometer and the axis of the headstock chuck coincide in the horizontal direction, and electrically connecting the fixed dynamometer with a data system; detecting the radial runout of the workpiece to be detected to ensure that the radial runout is not more than 0.002 mm; the fixed dynamometer measures original data of the headstock during material carrying idling and internal thread grinding, the original data are transmitted to the data system, and the data system processes the original data to finally obtain the grinding force. The grinding force measuring method for the internal thread grinding process can conveniently measure the grinding force of the internal thread grinding process, and has the advantages of accurate and reliable measuring result, simple structure and convenient assembly.)

1. A grinding force measuring method in the internal thread grinding process is characterized by comprising the following steps:

installing a workpiece to be tested: fixing a workpiece to be measured on a fixed dynamometer, installing the fixed dynamometer on a headstock chuck of a machine tool, ensuring that the axis of the workpiece to be measured, the axis of the fixed dynamometer and the axis of the headstock chuck are superposed in the horizontal direction, and electrically connecting the fixed dynamometer with a data system;

detecting the radial runout of the workpiece to be detected: detecting the radial runout of the workpiece to be detected to ensure that the radial runout is not more than 0.002 mm;

and (3) grinding force measurement: the fixed dynamometer measures original data of a headstock with material idling and internal thread grinding, the original data are transmitted to the data system, and the data system processes the original data to finally obtain the grinding force.

2. The grinding force measuring method in the internal thread grinding process according to claim 1, wherein the fixed dynamometer includes a force sensor and a clamping fixture, a workpiece to be measured is fixed to one end of the force sensor, the other end of the force sensor is fixed to one end of the clamping fixture, and the other end of the clamping fixture is fixed to the headstock chuck; the force sensor is electrically connected to the data system.

3. A grinding force measuring method in a female screw grinding process according to claim 2, wherein in said grinding force measuring step, said data system processes raw data in a process of:

headstock belt material idle running data processing: the data system receives the x-axis direction force F measured by the force sensor when the headstock belt material idles_xkFrom which data F 'of grinding force steady state is extracted'_xkFourier transform is carried out to determine the amplitude F under the rotating speed frequency of the head frame chuck_xk_1；

Data processing of grinding: the data system receives the force F in the x-axis direction measured by the force sensor during grinding of the internal thread of the workpiece to be measured_xmY-axis direction force F_ymZ-axis direction force F_zmAnd moment M of z-axis_zmFrom which data F 'of grinding force steady state is extracted'_xm、F′_ym、F′_zm、M′_zmAnd comparing the intercepted data F'_xmAnd F'_ymRespectively carrying out Fourier transform, extracting direct current components, and subtracting interference data F' of the direct current components in a time domain_xmAnd F ″)_ym；

Calculated according to the following formula:

F_t＝M'_zm/R

F_s＝F′_zm

G＝F_{xk_1}

finally obtaining the grinding force F_m：

Wherein R is the radius of the inner circle of the workpiece to be measured, the x-axis direction represents the radial direction, the y-axis direction represents the tangential direction, the z-axis direction represents the axial direction, and F_n、F_t、F_sThe grinding radial, tangential and axial forces of the internal thread are respectively.

4. A grinding force measuring method of an internal thread grinding process according to claim 2, wherein the force sensor is a six-dimensional force sensor.

5. The grinding force measuring method for the internal thread grinding process according to any one of claims 1 to 3, wherein in the grinding force measuring step, a specific test procedure is as follows:

opening the data system, selecting a channel, recording the rotating speed information of the workpiece to be detected in the equipment name column, clicking a link button, and resetting the index of the force sensor;

setting the program of the headstock material carrying idling experiment to be consistent with the information recorded by the acquisition software, and starting to acquire and store the original data of the headstock material carrying idling experiment;

trimming a grinding wheel on line and adjusting the tool;

opening the data system, selecting a channel, recording the rotating speed of the grinding wheel, the rotating speed of a workpiece to be measured and the feeding amount in a column of equipment name, clicking a link button, and resetting the index of the force sensor;

setting numerical control program parameters, starting feeding, collecting and storing original data during internal thread grinding;

and clearing the readings of the force sensor to prepare for the next feed.

6. The grinding force measuring method of an internal thread grinding process according to any one of claims 1 to 3, characterized by further comprising, before the step of mounting a workpiece to be measured, the steps of: and checking and recording the temperature and humidity of the constant-temperature constant-humidity workshop, starting up to detect the state of the machine tool, and starting and warming up the machine tool to a stable state.

7. A grinding force measuring method in an internal thread grinding process according to any one of claims 1 to 3, characterized by further comprising, before the step of detecting radial run-out of the workpiece to be measured, the steps of: and measuring the radius of the inner circle of the workpiece to be measured.

8. A grinding force measuring method in an internal thread grinding process according to any one of claims 1 to 3, wherein in the step of detecting run-out of the workpiece to be measured, the run-out amount includes an inside run-out amount and an outside run-out amount.

Technical Field

The invention relates to the technical field of sensors and measurement, in particular to a grinding force measuring method in an internal thread grinding process.

Background

Disclosure of Invention

The present invention is directed to solving at least one of the problems of the prior art. Therefore, an object of the present invention is to provide a grinding force measuring method for an internal thread grinding process, which can conveniently measure the grinding force of the internal thread grinding process, and has the advantages of accurate and reliable measurement result, simple structure and convenient assembly.

The grinding force measuring method for the internal thread grinding process comprises the following steps:

installing a workpiece to be tested: fixing a workpiece to be measured on a fixed dynamometer, installing the fixed dynamometer on a headstock chuck of a machine tool, ensuring that the axis of the workpiece to be measured, the axis of the fixed dynamometer and the axis of the headstock chuck are superposed in the horizontal direction, and electrically connecting the fixed dynamometer with a data system;

detecting the radial runout of the workpiece to be detected: detecting the radial runout of the workpiece to be detected to ensure that the radial runout is not more than 0.002 mm;

and (3) grinding force measurement: the fixed dynamometer measures original data of a headstock with material idling and internal thread grinding, the original data are transmitted to the data system, and the data system processes the original data to finally obtain the grinding force.

According to the grinding force measuring method for the internal thread grinding process, the workpiece to be measured is fixed on the fixed dynamometer, the fixed dynamometer is installed on the headstock chuck of the machine tool, the headstock chuck of the machine tool can drive the fixed dynamometer and the workpiece to be measured to rotate at a low speed, and the force of the workpiece to be measured acting on the fixed dynamometer can be measured through the fixed dynamometer; the workpiece to be measured, the fixed dynamometer and the headstock chuck are arranged in the horizontal direction, and the radial runout of the workpiece to be measured is detected to ensure that the radial runout is not more than 0.002mm, so that the axial line of the workpiece to be measured, the axial line of the fixed dynamometer and the axial line of the headstock chuck are coincided in the horizontal direction, the measuring result is prevented from being influenced by gravity factors, and the accuracy and reliability of the measured grinding force are ensured; the fixed dynamometer transmits original data of the headstock during material carrying idling and internal thread grinding to the data system through the data line, and the data system processes the original data to obtain the grinding force, so that the result is accurate and reliable. In conclusion, the grinding force measuring method for the internal thread grinding process can conveniently measure the grinding force of the internal thread grinding process, and has the advantages of accurate and reliable measuring result, simple structure and convenience in assembly.

According to one embodiment of the invention, the fixed dynamometer comprises a force sensor and a clamping tool, a workpiece to be measured is fixed with one end of the force sensor, the other end of the force sensor is fixed with one end of the clamping tool, and the other end of the clamping tool is fixed with the headstock chuck; the force sensor is electrically connected to the data system.

According to a further embodiment of the present invention, in the grinding force measuring step, the data system processes the raw data by:

headstock belt material idle running data processing: the data system receives the x-axis direction force F measured by the force sensor when the headstock belt material idles_xkFrom which data F 'of grinding force steady state is extracted'_xkFourier transform is carried out to determine the amplitude F under the rotating speed frequency of the head frame chuck_xk_1；

Data processing of grinding: the data system receives the force F in the x-axis direction measured by the force sensor during grinding of the internal thread of the workpiece to be measured_xmY-axis direction force F_ymZ-axis direction force F_zmAnd moment M of z-axis_zmFrom which the grinding force is taken out in a stable mannerData of state F'_xm、F'_ym、F'_zm、M'_zmAnd comparing the intercepted data F'_xmAnd F'_ymFourier transform is performed to extract DC components, and interference data F of the DC components are subtracted in time domain "_xmAnd F "_ym；

Calculated according to the following formula:

F_t＝M'_zm/R

F_s＝F'_zm

G＝F_{xk_1}

finally obtaining the grinding force F_m：

Wherein R is the radius of the inner circle of the workpiece to be measured,_xaxial direction means radial direction, y-axis direction means tangential direction, z-axis direction means axial direction, F_n、F_t、F_sThe grinding radial, tangential and axial forces of the internal thread are respectively.

According to a further embodiment of the invention, the force sensor is a six-dimensional force sensor.

According to some embodiments of the present invention, in the step of measuring the grinding force, a specific test procedure is as follows:

opening the data system, selecting a channel, recording the rotating speed information of the workpiece to be detected in the equipment name column, clicking a link button, and resetting the index of the force sensor;

setting the program of the headstock material carrying idling experiment to be consistent with the information recorded by the acquisition software, and starting to acquire and store the original data of the headstock material carrying idling experiment;

trimming a grinding wheel on line and adjusting the tool;

opening the data system, selecting a channel, recording the rotating speed of the grinding wheel, the rotating speed of a workpiece to be measured and the feeding amount in a column of equipment name, clicking a link button, and resetting the index of the force sensor;

setting numerical control program parameters, starting feeding, collecting and storing original data during internal thread grinding;

and clearing the readings of the force sensor to prepare for the next feed.

According to some embodiments of the invention, before the step of mounting the workpiece to be tested, the method further comprises the following steps: and checking and recording the temperature and humidity of the constant-temperature constant-humidity workshop, starting up to detect the state of the machine tool, and starting and warming up the machine tool to a stable state.

According to some embodiments of the present invention, before the step of detecting the radial run-out of the workpiece to be measured, the method further comprises the following steps: and measuring the radius of the inner circle of the workpiece to be measured.

According to some embodiments of the present invention, in the step of detecting the radial run-out of the workpiece to be measured, the radial run-out amount includes an inner run-out amount and an outer run-out amount.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

fig. 1 is a schematic diagram illustrating a grinding force measuring method of an internal thread grinding process according to an embodiment of the present invention.

Fig. 2 is a schematic view illustrating the assembly of a fixed dynamometer and a workpiece to be measured in the grinding force measuring method in the internal thread grinding process according to the embodiment of the present invention.

Fig. 3 is a schematic view of coordinate transformation used in the grinding force measuring method in the internal thread grinding process according to the embodiment of the present invention.

Reference numerals:

workpiece 1 to be measured

Fixed dynamometer 2 force sensor (six-dimensional force sensor) 201 clamping tool 202

Headstock chuck 3

Grinding wheel motor 4

Grinding wheel 5

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are illustrative only for the purpose of explaining the present invention, and are not to be construed as limiting the present invention.

A grinding force measuring method of an internal thread grinding process according to an embodiment of the present invention will be described below with reference to fig. 1 to 3.

The grinding force measuring method for the internal thread grinding process comprises the following steps:

installing a workpiece to be tested 1: fixing a workpiece 1 to be measured on a fixed dynamometer 2, installing the fixed dynamometer 2 on a headstock chuck 3 of a machine tool, ensuring that the axis of the workpiece 1 to be measured, the axis of the fixed dynamometer 2 and the axis of the headstock chuck 3 are superposed in the horizontal direction, and electrically connecting the fixed dynamometer 2 with a data system;

detecting the radial runout of the workpiece 1 to be detected: detecting the radial runout of the workpiece 1 to be detected, and ensuring that the radial runout is not more than 0.002 mm;

and (3) grinding force measurement: the fixed dynamometer 2 is used for measuring original data of the headstock during material carrying idling and internal thread grinding, the original data are transmitted to the data system, and the data system processes the original data to finally obtain the grinding force.

Specifically, a workpiece 1 to be measured is fixed on a fixed dynamometer 2, and the force of the workpiece 1 to be measured acting on the fixed dynamometer 2 can be measured through the fixed dynamometer 2; the fixed dynamometer 2 is installed on a headstock chuck 3 of a machine tool, the fixed dynamometer 2 and a workpiece 1 to be measured can be driven to rotate at a low speed through the headstock chuck 3 of the machine tool, the axis of the workpiece 1 to be measured, the axis of the fixed dynamometer 2 and the axis of the headstock chuck 3 are overlapped in the horizontal direction, namely the workpiece 1 to be measured, the fixed dynamometer 2 and the headstock chuck 3 are arranged in the horizontal direction, the influence on a measurement result due to gravity factors is avoided, and the accuracy and reliability of the measured grinding force are guaranteed; the fixed dynamometer 2 is electrically connected with a data system, so that the data system can conveniently acquire original data measured by the fixed dynamometer 2.

It should be noted that, the workpiece 1 to be measured and the fixed dynamometer 2 can be fixed by screws, and the assembly is simple and reliable.

Detecting the radial runout of the workpiece 1 to be detected, and ensuring that the radial runout is not more than 0.002 mm; in this way, it is ensured that the axes of the workpiece 1 to be measured, of the stationary dynamometer 2 and of the headstock chuck 3 coincide in the horizontal direction.

The fixed dynamometer 2 measures original data of the headstock during material-carrying idling and internal thread grinding, the original data are transmitted to the data system, the data system processes the original data, and finally the grinding force is obtained.

According to the grinding force measuring method for the internal thread grinding process, the workpiece to be measured 1 is fixed on the fixed dynamometer 2 through screws, the fixed dynamometer 2 is installed on the headstock chuck 3 of the machine tool, the headstock chuck 3 of the machine tool can drive the fixed dynamometer 2 and the workpiece to be measured 1 to rotate at a low speed, and the force of the workpiece to be measured 1 acting on the fixed dynamometer 2 can be measured through the fixed dynamometer 2; the workpiece to be measured 1, the fixed dynamometer 2 and the headstock chuck 3 are arranged in the horizontal direction, and the radial runout of the workpiece to be measured 1 is detected to ensure that the radial runout is not more than 0.002mm, so that the axis of the workpiece to be measured 1, the axis of the fixed dynamometer 2 and the axis of the headstock chuck 3 are coincided in the horizontal direction, the measurement result is prevented from being influenced by gravity factors, and the accuracy and reliability of the measured grinding force are ensured; the fixed dynamometer 2 transmits original data of the headstock during material carrying idling and internal thread grinding to a data system through a data line, and the data system processes the original data to obtain the grinding force, so that the result is accurate and reliable. In conclusion, the grinding force measuring method for the internal thread grinding process can conveniently measure the grinding force of the internal thread grinding process, and has the advantages of accurate and reliable measuring result, simple structure and convenience in assembly.

According to one embodiment of the invention, the fixed dynamometer 2 comprises a force sensor 201 and a clamping tool 202, the workpiece 1 to be measured is fixed with one end of the force sensor 201, the other end of the force sensor 201 is fixed with one end of the clamping tool 202, and the other end of the clamping tool 202 is fixed with the headstock chuck 3; the force sensor 201 is electrically connected to a data system. Specifically, the workpiece 1 to be measured, the force sensor 201 and the clamping tool 202 are assembled into a whole, the force sensor 201 and the data system are connected through a data line, and the clamping tool 202 is clamped on the headstock chuck 3, so that the workpiece 1 to be measured and the force sensor 201 can be firmly fixed, and the grinding force can be conveniently measured.

It should be noted that, the force sensor 201 and the clamping fixture 202 may be connected by screws, and the assembly is simple and reliable.

According to a further embodiment of the invention, in the grinding force measuring step, the data system processes the raw data by:

headstock belt material idle running data processing: the data system receives the x-axis direction force F measured by the force sensor 201 when the headstock strap idles_xkFrom which data F 'of grinding force steady state is extracted'_xkFourier transform is carried out to determine the amplitude F under the rotating speed frequency of the headstock chuck 3_xk_1；

Data processing of grinding: the data system receives the force F in the x-axis direction measured by the force sensor 201 during the grinding of the internal thread of the workpiece 1 to be measured_xmY-axis direction force F_ymZ-axis direction force F_zmAnd moment M of z-axis_zmFrom which data F 'of grinding force steady state is extracted'_xm、F'_ym、F'_zm、M'_zmAnd comparing the intercepted data F'_xmAnd F'_ymFourier transform is performed to extract DC components, and interference data F of the DC components are subtracted in time domain "_xmAnd F "_ym；

Calculated according to the following formula:

F_t＝M'_zm/R

F_s＝F_z'_m

G＝F_{xk_1}

finally obtaining the grinding force F_m：

Wherein R is the radius of the inner circle of the workpiece 1 to be measured, the x-axis direction represents the radial direction, the y-axis direction represents the tangential direction, the z-axis direction represents the axial direction, and F_n、F_t、F_sThe grinding radial, tangential and axial forces of the internal thread are respectively.

It can be understood that the grinding force can be calculated and the measurement result of the grinding force is accurate and reliable by processing the raw data of the headstock strap material idling and the raw data of the internal thread grinding measured by the force sensor 201 by the data system.

According to a further embodiment of the invention, the force sensor 201 is a six-dimensional force sensor 201. It can be understood that a coordinate system O' -xyz is established in the center of the six-dimensional torque sensor, the six-dimensional torque sensor can detect the force applied to the six-dimensional torque sensor in the x-axis direction, the force applied to the six-dimensional torque sensor in the y-axis direction, the force applied to the six-dimensional torque sensor in the z-axis direction, the moment applied to the six-dimensional torque sensor in the x-axis direction, the moment applied to the six-dimensional torque sensor in the y-axis direction and the moment applied to the six-dimensional torque sensor in the z-axis direction, the grinding force in the internal thread grinding process can be accurately calculated through the detection value of the six-dimensional torque sensor, and the grinding force calculation result is accurate and reliable.

According to some embodiments of the present invention, in the step of measuring the grinding force, the specific test flow is as follows:

and opening a data system, selecting a channel, recording the rotating speed information of the workpiece 1 to be measured in the equipment name column, clicking a link button, and resetting the index of the force sensor 201, so that the original data can be acquired and stored when the headstock is in a material-carrying idle state.

Setting the program of the headstock material carrying idling experiment to be consistent with the information recorded by the acquisition software, and starting to acquire and store the original data of the headstock material carrying idling experiment; it can be understood that, according to the needs of actual conditions, the procedure of the headstock material idling experiment is changed, the procedure of the headstock material idling experiment is kept consistent with the information recorded by the acquisition software, and the data system can conveniently process the original data.

Trimming the grinding wheel 5 on line and setting the tool; therefore, the axis of the grinding wheel 5 is coincident with the axis of the workpiece 1 to be measured, so that the grinding wheel 5 can smoothly grind the internal thread of the workpiece 1 to be measured, and the accuracy of a grinding force measurement result is improved.

Opening a data system, selecting a channel, recording the rotating speed of the grinding wheel 5, the rotating speed of the workpiece 1 to be measured and the feeding amount in the column of the equipment name, clicking a link button, and resetting the reading of the force sensor 201; therefore, the raw data can be collected and stored during internal thread grinding.

Setting numerical control program parameters, starting feeding, collecting and storing original data during internal thread grinding; it can be understood that, in the internal thread grinding process, the grinding wheel motor 4 electrically drives the grinding wheel 5 to rotate at a high speed and feed, the headstock chuck 3, the clamping tool 202, the six-dimensional torque sensor and the workpiece 1 to be measured synchronously rotate at a low speed, the six-dimensional torque sensor collects original data during internal thread grinding and transmits the original data to the data system, and the data system processes the original data to finally obtain the grinding force.

The force sensor 201 is cleared to count in preparation for the next feed.

According to some embodiments of the present invention, before the step of mounting the workpiece 1 to be tested, the following steps are further included: the temperature and the humidity of the constant-temperature constant-humidity workshop are checked and recorded, and it can be understood that the measurement result of the six-dimensional torque sensor is accurate when the workshop is in a constant-temperature constant-humidity state, so that the influence on the measurement result due to the temperature and humidity change in the workshop is avoided; and starting up the machine tool to detect the state of the machine tool, starting up the machine tool and warming up the machine tool to a stable state, thereby ensuring the normal work of the machine tool and improving the accuracy of a measuring result.

According to some embodiments of the present invention, before the step of detecting the radial run-out of the workpiece 1 to be measured, the following steps are further included: and measuring the radius of the inner circle of the workpiece 1 to be measured. Therefore, the grinding force in the internal thread grinding process can be calculated conveniently by processing the original data subsequently.

According to some embodiments of the present invention, in the step of detecting the radial run-out of the workpiece 1 to be measured, the radial run-out amount includes an inner run-out amount and an outer run-out amount. It can be understood that the radial runout amount of the inner side and the radial runout amount of the outer side of the workpiece 1 to be measured are respectively detected, and the radial runout amount of the inner side of the workpiece 1 to be measured and the radial runout amount of the outer side of the workpiece 1 to be measured are both not more than 0.002mm, so that the coincidence of the inner ring axis of the workpiece 1 to be measured, the outer ring axis of the workpiece 1 to be measured, the axis of the fixed dynamometer 2 and the axis of the headstock chuck 3 in the horizontal direction is ensured.

The grinding force measuring method of the internal thread grinding process of the present invention will be described below in a specific embodiment.

The test procedure for this example is as follows:

step S1: checking and recording the temperature and humidity of the constant-temperature constant-humidity workshop, starting up to detect the state of the machine tool, and starting and warming up the machine to a stable state;

step S2: one end of the force sensor 201 is fixed with the workpiece 1 to be measured, and the other end of the force sensor 201 is fixed with one end of the clamping tool 202, so that the workpiece 1 to be measured, the force sensor 201 and the clamping tool 202 are assembled into a whole, the force sensor 201 is electrically connected with a data system through a data line, and voltage is provided;

step S3: measuring the radius of the inner circle of the workpiece 1 to be measured;

step S4: fixing the other end of the clamping tool 202 with the headstock chuck 3, and respectively detecting the radial runout quantity of the inner side and the radial runout quantity of the outer side of the workpiece 1 to be detected;

step S5: opening a data system, selecting a channel, recording the rotating speed information of the workpiece 1 to be measured in the equipment name column, clicking a link button, and resetting the reading of the force sensor 201;

step S6: setting the program of the headstock material carrying idling experiment to be consistent with the information recorded by the acquisition software, and starting to acquire and store the original data of the headstock material carrying idling experiment;

step S7: trimming the grinding wheel 5 on line and setting the tool;

step S8: opening a data system, selecting a channel, recording the rotating speed of the grinding wheel 5, the rotating speed of the workpiece 1 to be measured and the feeding amount in the column of the equipment name, clicking a link button, and resetting the reading of the force sensor 201;

step S9: setting numerical control program parameters, starting feeding, collecting and storing original data during internal thread grinding;

step S10: clearing the readings of the force sensor 201 to prepare for the next feed;

step S11: and (6) continuing to measure if necessary, and repeating the step, such as not needing to unload the workpiece 1 to be measured and shut down.

The steps of the data system of this embodiment for processing test data are as follows:

and (3) converting a coordinate system: as shown in FIG. 3, a coordinate system O-F is established at the connecting position of the workpiece spindle and the tool_tF_nF_sAnd establishing a coordinate system O' -xyz at the central position of the force sensor 201, wherein the two coordinate systems are coaxial, and the two coordinate systems have a difference of a rotation angle omega tau. F_x、F_y、F_zIs a real force, F_n、F_t、F_sThe grinding forces of the internal thread in the radial direction, the tangential direction and the axial direction are respectively, omega is the angular velocity of the headstock, and the contact point of the grinding wheel 5 and the workpiece is ensured to be right below the vertical center in the grinding process. Component force F of grinding on axial section_pComprises the following steps:

headstock belt material idle running data processing: the data system receives the x-axis direction force F measured by the force sensor 201 when the headstock strap idles_xkFrom which data F 'of grinding force steady state is extracted'_xkFourier transform is carried out to determine the amplitude F under the rotating speed frequency of the headstock chuck 3_xk_1；

Data processing of grinding: the data system receives the force F in the x-axis direction measured by the force sensor 201 during the grinding of the internal thread of the workpiece 1 to be measured_xmY-axis direction force F_ymZ-axis direction force F_zmAnd moment M of z-axis_zmFrom which data F 'of grinding force steady state is extracted'_xm、F'_ym、F'_zm、M'_zmAnd comparing the intercepted data F'_xmAnd F'_ymFourier transform is performed to extract DC components, and interference data F of the DC components are subtracted in time domain "_xmAnd F "_ym；

Calculated according to the following formula:

F_t＝M'_zm/R

F_s＝F'_zm

G＝F_{xk_1}

finally obtaining the grinding force F_m：

Wherein R is the radius of the inner circle of the workpiece 1 to be measured, the x-axis direction represents the radial direction, the y-axis direction represents the tangential direction, the z-axis direction represents the axial direction, and F_n、F_t、F_sThe grinding radial, tangential and axial forces of the internal thread are respectively.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an illustrative embodiment," "an example," "a specific example," or "some examples" or the like mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

While embodiments of the invention have been shown and described, it will be understood by those of ordinary skill in the art that: various changes, modifications, substitutions and alterations can be made to the embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.