Internal thread grinding cooling adjusting method based on grinding force

Abstract

The internal thread grinding cooling adjusting method based on the grinding force comprises the steps that a grinding test piece is measured, and the size of the grinding test piece is obtained; a grinding test piece, a torque and rotating speed sensor and a three-component dynamometer are installed on the internal thread grinding machine; torque and rotating speed sensor calibration is carried out; recording is stopped after one feeding process is completed; performing data processing on data of the torque and rotating speed sensor and the three-component dynamometer recorded in the feeding process to obtain measurement data of all grinding forces in the feeding process; calculating a theoretical tangential grinding force Ft'and a theoretical normal grinding force Fn '; and cooling parameters, namely the cooling liquid flow Q and the cooling liquid pressure P, are adjusted until the theoretical grinding force is equal to the actually measured grinding force. The grinding force is measured, according to the force-heat coupling relation and a large amount of test data, the cooling liquid flow, the flow speed and other parameters are controlled, and the purposes of protecting the workpiece surface, improving the grinding efficiency, restraining surface burning and improving the grinding precision are achieved.

Description

Technical Field

[0001] The present invention relates to a method for regulating the cooling of internal thread grinding based on grinding force, belonging to the technical field of internal thread grinding. Background Art

[0002] During the internal thread grinding process, the grinding wheel needs to penetrate into the workpiece cavity to grind the inner wall for threads. When the high-speed rotating grinding wheel contacts the workpiece, a large amount of grinding heat is generated, causing the temperature in the machining area to rise instantaneously. Seriously, it will cause surface burns of the workpiece and reduce the service life of the grinding wheel. The heat conducts inside the workpiece to other parts, resulting in thermal elongation of the workpiece and a decrease in the precision of the internal thread. Therefore, grinding coolant is required to cool the grinding wheel and the workpiece during the grinding process.

[0003] In the existing forming grinding cooling state monitoring device, the semi-artificial thermocouple wire of the temperature measurement part and the pressure measurement hole of the pressure measurement part are both perpendicular to the machining surface and penetrate the workpiece to be machined. For workpieces that need internal thread grinding, it may damage the surface structures inside and outside the workpiece. During the internal thread grinding process, the grinding wheel needs to penetrate into the workpiece cavity to grind the inner wall for threads. The existing method senses the grinding heat during the machining process through a temperature sensor and adjusts the grinding parameters accordingly. However, this method will damage the workpiece surface and is difficult to apply in the internal thread grinding process. Summary of the Invention

[0004] The technical problem to be solved by the present invention is: overcoming the deficiencies of the prior art, the present invention proposes a method for regulating the cooling of internal thread grinding based on grinding force, avoiding damaging the inner and outer surfaces of the workpiece and being more suitable for the internal thread grinding process.

[0005] The technical solution adopted by the present invention is: a method for regulating the cooling of internal thread grinding based on grinding force, including:

[0006] Measuring a grinding specimen to obtain the dimensions of the grinding specimen;

[0007] Installing the grinding specimen, torque and speed sensor, and three-component dynamometer on an internal thread grinding machine;

[0008] Calibrating the torque and speed sensor;

[0009] Starting the internal thread grinding machine, completing the tool alignment, setting the three-jaw chuck to rotate at a speed of ω v and a feed rate of ap, and the grinding wheel speed of ω s , starting the torque and speed sensor and the three-component dynamometer and recording data until the recording is stopped after completing one feed process;

[0010] Processing the data of the torque and speed sensor and the three-component dynamometer recorded during this feed process to obtain the measured grinding force data during this feed process;

[0011] Calculate the angle φ through which the abrasive grains of the grinding wheel rotate from entering the grinding zone to leaving the grinding zone;

[0012] Calculate the dynamic contact arc length l of thread grinding k ;

[0013] According to the angle φ and the dynamic contact arc length l of thread grinding k , calculate the theoretical tangential grinding force F t ' and the theoretical normal grinding force F n ';

[0014] Adjust the cooling parameters, i.e., the coolant flow rate Q and the cooling hydraulic pressure P, until the theoretical grinding force is equal to the measured grinding force.

[0015] Furthermore, the measuring of the grinding specimen includes: determining the material of the grinding specimen, the inner hole diameter d1, the outer circle diameter d2, the total length l1 of the workpiece, the inner hole depth l2, calculating the total weight G1 of the grinding specimen, and finding the center of gravity position of the grinding specimen.

[0016] Furthermore, the installation of the grinding specimen, the torque and speed sensor, and the three-component dynamometer on the internal thread grinding machine includes:

[0017] Fix the three-jaw chuck on the internal thread grinding machine, clamp the bushing with the three jaws on the three-jaw chuck. One end of the bushing is connected to the torque and speed sensor, the torque and speed sensor is connected to the torque and speed sensor base, and the torque and speed sensor base is fixed on the internal thread grinding machine; the other end of the torque and speed sensor is connected to the three-component dynamometer base, the three-component dynamometer base is installed in the bearing hole of the torque and speed sensor base through a bearing, and the bearing is axially positioned by a snap ring and a bearing baffle; the three-component dynamometer is connected to the three-component dynamometer base, and the grinding specimen is connected to the three-component dynamometer.

[0018] Furthermore, the calibration of the torque and speed sensor includes:

[0019] Start the internal thread grinding machine, turn on the torque and speed sensor and the three-component dynamometer in the stationary state and record the measured data. After standing for t1 seconds, set the three-jaw chuck to rotate at a speed of ω v and record the measured data of the torque and speed sensor and the three-component dynamometer. Adjust the torque and speed sensor so that the measured data of the torque and speed sensor in the first t1 seconds is 0; t1 is a set value;

[0020] Adjust the three-component dynamometer so that the data of the three-component dynamometer in the x-axis and y-axis directions are respectively:

[0021] x = G 1x0 sin(ω v t + γ)

[0022] y = G1y0 cos(ω v t + γ),

[0023] where G 1x0 is the initial gravity component of the three - component force sensor in the x - axis direction; G 1y0 is the initial gravity component of the three - component force sensor in the y - axis direction; t is the rotation time; γ is the angle between the initial gravity direction and the x - axis, and tanγ = G 1y0 / G 1x0 .

[0024] Furthermore, the data of the torque - speed sensor and the three - component force sensor recorded during this feed process are processed to obtain the measurement data of all grinding forces during this feed process:

[0025] The tangential force F t of high - speed internal - thread grinding during this feed process is:

[0026] T1 is the reading recorded by the torque - speed sensor;

[0027] The time values corresponding to the curves obtained by subtracting G1sin(ω v t + γ) and G1cos(ω v t + γ) from the time - domain data in the x - axis and y - axis directions of the three - component force sensor are subjected to Fourier transform to process the time - domain data into frequency - domain data;

[0028] According to the grinding - wheel speed ω s and the diameter d s of the used grinding wheel, the grinding - wheel rotation frequency f s is calculated, and then the values of the frequency - domain data in the x - axis and y - axis directions corresponding to f s are F x and F y respectively;

[0029] The total grinding force F 总 of high - speed internal - thread grinding during this feed process is:

[0030]

[0031] According to the total grinding force F 总 of high - speed internal - thread grinding and the tangential force F t of high - speed internal - thread grinding, the normal force F n of high - speed internal - thread grinding is calculated as:

[0032]

[0033] Furthermore, the angle

[0034]

[0035]

[0036] wherein, l φ is the chord length corresponding to the angle φ at the maximum outer circle of the grinding wheel; a is the axial distance between the grinding wheel and the grinding specimen; S φ is the area of the triangle formed by the radius of the grinding wheel, the radius of the grinding specimen, and the axial distance between the grinding wheel and the grinding specimen; p is the semi-perimeter of the triangle formed by the radius of the grinding wheel, the radius of the grinding specimen, and the axial distance between the grinding wheel and the grinding specimen.

[0037] Furthermore, the dynamic contact arc length of thread grinding

[0038] wherein, d s is the diameter of the grinding wheel; v s is the linear velocity of the rotational motion of the grinding wheel; v d is the linear velocity of the linear motion of the grinding specimen; v w is the linear velocity of the rotational motion of the grinding specimen; α is the included angle between the axis of the grinding wheel and the axis of the grinding specimen.

[0039] Furthermore, the theoretical tangential grinding force F t ’ and the theoretical normal grinding force F n ’ are:

[0040]

[0041] wherein, z0 represents the length of the workpiece in the z-axis direction;

[0042] The single-layer tangential grinding force F t0 and the single-layer normal grinding force F n0 are respectively:

[0043]

[0044] The dynamically effective number of abrasive grains N d = l k · N t ,

[0045] wherein, l k is the dynamic contact arc length of thread grinding, N t is the mesh number of the grinding wheel; F p is the unit grinding force; a g is the total grinding depth; θ0 is the semi-apex angle of a single abrasive grain.

[0046] Furthermore, a method for regulating the cooling of internal thread grinding based on grinding force further includes:

[0047] Calculating the heat source intensity g;

[0048] Establish the grinding temperature field of the grinding specimen, and obtain the maximum temperature T on the surface of the grinding specimen max ;

[0049] The heat source intensity

[0050] Among them, the total grinding heat power P 总 is:

[0051]

[0052] J q is the mechanical equivalent of heat;

[0053] The ratio R of the grinding heat transferred into the grinding specimen w is:

[0054]

[0055] Among them, λ is the heat transfer coefficient; ρ is the density; c is the specific heat capacity; S n is the contact area between the grinding wheel and the workpiece during internal thread grinding;

[0056] The subscript s represents the grinding wheel; the subscript w represents the grinding specimen; the subscript f represents the grinding fluid;

[0057]

[0058] Among them, a is the distance between the axis of the grinding wheel and the workpiece; b is the tangential distance between the contact arc and the axis of the workpiece; c is the normal distance between the contact arc and the axis of the workpiece; β is the thread profile angle;

[0059] V is the volume of metal removed per unit time,

[0060] Furthermore, the temperature field distribution of the grinding specimen along the z-axis is:

[0061]

[0062] Among them, T is the ambient temperature around the internal thread grinding workpiece; z represents the axial length, and s represents the complex variable;

[0063] b(t - s, z) is the convective heat transfer coefficient on the surface of the grinding specimen;

[0064] d(t - s, z) is the surface temperature distribution of the grinding specimen.

[0065] Furthermore, adjusting the cooling parameters of the coolant flow rate Q and the cooling hydraulic pressure P until the theoretical grinding force is equal to the measured grinding force includes:

[0066] Comparing the measured tangential force F of high-speed internal thread grindingt With the theoretical tangential grinding force F t ’, the normal force of high-speed internal thread grinding F n And the theoretical normal grinding force F n ’, according to F t ’-Q-P diagram and F n ’-Q-P diagram, increase or decrease the coolant flow rate Q and coolant pressure P in real time according to the corresponding cooling parameters until the theoretical grinding force is equal to the measured grinding force;

[0067] During adjustment, first adjust the coolant flow rate Q according to the tangential grinding force, and then adjust the coolant pressure P according to the normal grinding force, finally achieving the effect that the theoretical grinding force is equal to the measured grinding force.

[0068] The advantages of the present invention compared with the prior art are as follows:

[0069] (1) Without changing the original workpiece structure, the present invention measures the tangential and normal grinding forces during the internal thread grinding process in real time, controls influencing factors such as coolant flow rate and flow velocity, achieves the purpose of improving grinding efficiency, suppressing surface burn, and improving grinding accuracy, and at the same time accumulates the measurement data among the internal thread grinding force - grinding parameters - cooling state, providing data support for further optimizing grinding and cooling parameters.

[0070] (2) The present invention measures the change of internal thread grinding force in real time, enables the workpiece to reach the thermal equilibrium state faster, reduces temperature fluctuations, avoids grinding burns while improving the grinding accuracy; the present invention can avoid damaging the inner and outer surfaces of the workpiece and is more suitable for the internal thread grinding process; the present invention optimizes the coolant parameters and is more environmentally friendly and effective during the use of the coolant. Description of the Drawings

[0071] Figure 1 is the flowchart of the method of the present invention;

[0072] Figure 2 is the connection and clamping diagram;

[0073] Figure 3 is the sectional view of connection and clamping;

[0074] Figure 4 is the F t ’-Q-P example diagram. Detailed Embodiment

[0075] The following further describes the present invention in detail with reference to the drawings and specific embodiments:

[0076] An internal thread grinding cooling adjustment method based on grinding force includes an internal thread grinding force measurement method and a cooling parameter control method.

[0077] For the method of measuring the internal thread grinding force, it is first necessary to calibrate the workpiece to be measured and the sensor. Then, the sensor, the auxiliary tooling, and the workpiece to be ground are sequentially connected into an assembly and installed on the chuck of the internal thread grinding machine. When measuring the total grinding force of the high-speed internal thread, a three-component dynamometer is used to measure the normal and tangential grinding forces respectively, and unnecessary errors are eliminated after data processing. The measured force value of the dynamometer in the x or y direction is used as the normal grinding force, and the measured torque of the dynamometer in the z direction is divided by the grinding equivalent diameter as the tangential grinding force.

[0078] For the method of controlling the cooling parameters, by monitoring the magnitude of the grinding force in real time, the coolant flow rate and the coolant flow velocity are adjusted, and the number of passes, the feed rate, and the nozzle position for each thread grinding are reasonably arranged to achieve the optimization purpose.

[0079] As Figure 1 shown, the present invention provides an internal thread grinding cooling adjustment method based on the grinding force, including the following specific steps:

[0080] The first step: Measuring the grinding specimen

[0081] Determine the material of the grinding specimen, the inner hole diameter d1, the outer circle diameter d2, the total length of the workpiece l1, the inner hole depth l2, calculate the total weight G1 of the workpiece, and find the center of gravity position of the grinding specimen;

[0082] The second step: Connection and clamping

[0083] As Figure 2 , Figure 3 shown, the three-jaw chuck 1 is fixedly connected to the internal thread grinding machine. The shaft sleeve 2 is clamped by three jaws on the chuck. The shaft sleeve 2 is connected to the torque and speed sensor 3 through a flat key. The torque and speed sensor 3 is connected to the torque and speed sensor base 4 through screws. The torque and speed sensor base 4 is fixedly connected to the internal thread grinding machine. The bearing 5 is placed between the bearing hole of the torque and speed sensor base 4 and the three-component dynamometer base 6, and axial positioning is achieved through the snap ring 7 and the bearing baffle 8. Among them, the snap ring 7 is stuck on the protruding shaft of the three-component dynamometer base 6, and the bearing baffle 8 is connected to the torque and speed sensor base 4 through screws. The three-component dynamometer 9 is connected to the three-component dynamometer base 6 through screws. The grinding specimen 10 is connected to the three-component dynamometer 9 through screws;

[0084] The third step: Sensor calibration

[0085] Turn on the internal thread grinding machine. Turn on the torque and speed sensor 3 and the three-component dynamometer 9 in the static state and record the measured data. After standing for 10 s, set the three-jaw chuck 1 to rotate at a speed of ω vRotate, record the data measured by the torque and rotational speed sensor 3 and the three-component force measuring instrument 9, and adjust the torque and rotational speed sensor 3 so that the data measured in the first 10 s is 0. Adjust the three-component force measuring instrument 9 so that the data in the x and y directions are respectively:

[0086] x = G 1x0 sin(ω v t + γ)

[0087] y = G 1y0 cos(ω v t + γ)(1)

[0088] In the formula

[0089] G 1x0 —— The initial gravity component of the three-component force measuring instrument 9 on the x-axis;

[0090] G 1y0 —— The initial gravity component of the three-component force measuring instrument 9 on the y-axis;

[0091] t —— Rotation time;

[0092] γ —— The included angle between the initial gravity direction and the x-axis, tanγ = G 1y0 / G 1x0 ;

[0093] Step 4: Measure the grinding force during high-speed internal thread grinding

[0094] Start the internal thread grinding machine, complete the tool setting, and set the chuck to rotate at a speed of ω v Rotate, the feed rate is ap, and the grinding wheel speed is ω s , start the torque and rotational speed sensor 3 and the three-component force measuring instrument and record the data until the recording stops after a single feed process.

[0095] Step 5: Data processing

[0096] Set the reading recorded by the torque and rotational speed sensor 3 as T1, then the tangential force F t during the high-speed internal thread grinding in this feed process is:

[0097]

[0098] Subtract the values corresponding to the time of the curves of G1sin(ω v t + γ) and G1cos(ω v t + γ) from the time-domain data in the x and y directions of the three-component force measuring instrument respectively, and then through Fourier transform, process the time-domain data into frequency-domain data. According to the grinding wheel speed ω s and the diameter d s of the grinding wheel used, calculate the grinding wheel rotation frequency f s, then the frequency-domain data in the x and y directions correspond to f s The values are F x and F y , then the total grinding force F 总 for high-speed internal thread grinding during this feed process is:

[0099]

[0100] According to the total grinding force F 总 for high-speed internal thread grinding and the tangential grinding force F t for high-speed internal thread grinding, the normal grinding force F n for high-speed internal thread grinding is calculated as:

[0101]

[0102] Thus, the measurement data of all grinding forces during this feed process are obtained.

[0103] Step 6: Calculate the angle φ

[0104]

[0105] where

[0106] l φ —— The chord length corresponding to φ at the maximum outer circle of the grinding wheel;

[0107] a —— The distance between the grinding wheel and the workpiece axis;

[0108] S φ —— The area of the triangle formed by the grinding wheel radius, workpiece radius, and the distance between the grinding wheel and the workpiece axis;

[0109] p —— The semi-perimeter of the triangle formed by the grinding wheel radius, workpiece radius, and the distance between the grinding wheel and the workpiece axis.

[0110] Step 7: Calculate the dynamic contact arc length l k

[0111]

[0112] where

[0113] d s —— The grinding wheel diameter;

[0114] d w —— The workpiece diameter;

[0115] v s —— The linear velocity of the grinding wheel rotational motion;

[0116] v d—— Linear velocity of the workpiece in linear motion;

[0117] v w —— Linear velocity of the workpiece in rotational motion;

[0118] α —— Angle between the axis of the grinding wheel and the axis of the workpiece.

[0119] Step 8: Calculate the theoretical tangential grinding force F t ’ and the theoretical normal grinding force F n ’

[0120] According to the dynamic contact arc length l k of thread grinding and the number of mesh N t of the grinding wheel, the dynamic effective number of abrasive grains N d can be obtained as follows:

[0121] N d = l k ·N t (9)

[0122] The single-layer tangential grinding force F t0 and the single-layer normal grinding force F n0 are expressed as:

[0123]

[0124] In the formula

[0125] F p —— Unit grinding force;

[0126] ag —— Total grinding depth;

[0127] θ0 —— Half apex angle of a single abrasive grain.

[0128] Then the theoretical tangential grinding force F t ’ and the theoretical normal grinding force F n ’ can be expressed as:

[0129]

[0130] z0 represents the length of the workpiece in the z-axis direction;

[0131] Step 9: Calculate the heat source intensity g

[0132] During thread grinding, the grinding heat power per unit time includes the heat P w transferred to the workpiece, the heat P s transferred to the grinding wheel, the heat P f transferred to the grinding fluid, and the heat P ch carried away by the chips.

[0133] The total grinding heat power P 总 can be expressed as:

[0134]

[0135] In the formula

[0136] J q ——Thermal equivalent of work.

[0137] Ratio R of grinding heat transferred into the workpiece w is:

[0138]

[0139] In the formula

[0140] λ——Heat transfer coefficient;

[0141] ρ——Density;

[0142] c——Specific heat capacity;

[0143] The subscript indicates:

[0144] s——Grinding wheel;

[0145] w——Workpiece;

[0146] f——Grinding fluid.

[0147] S n ——Contact area between the grinding wheel and the workpiece during internal thread grinding.

[0148]

[0149] In the formula

[0150] a——Axial distance between the grinding wheel and the workpiece;

[0151] b——Tangential distance between the contact arc and the axis of the workpiece;

[0152] c——Normal distance between the contact arc and the axis of the workpiece.

[0153] β——Thread profile angle.

[0154] Then the heat source intensity can be expressed as:

[0155]

[0156] In the formula

[0157] V——Volume of metal removed per unit time.

[0158]

[0159] Step 10: Establish the grinding temperature field and correct the grinding temperature field through the grinding force cooling test;

[0160] The temperature field distribution of the internally threaded grinding workpiece along the z-axis can be expressed as:

[0161]

[0162] In the formula

[0163] T —— the ambient temperature around the internally threaded grinding workpiece;

[0164] b(t - s, z) —— the convective heat transfer coefficient on the workpiece surface;

[0165] d(t - s, z) —— the temperature distribution on the workpiece surface;

[0166] λ —— the heat transfer coefficient.

[0167] z represents the axial length, and s represents a complex variable;

[0168] From this, the maximum temperature T on the workpiece surface can be obtained max .

[0169] Step 11: Adjust the cooling parameters, namely the coolant flow rate Q and the cooling hydraulic pressure P;

[0170] Compare F t with F t ’, F n with F n ’, and according to the F t ’-Q-P diagram (as shown in Figure 4 ) and the corresponding cooling parameters in the F n ’-Q-P diagram, increase or decrease the coolant flow rate Q and the cooling hydraulic pressure P in real time until the theoretical grinding force is equal to the measured grinding force. Among them, the F t ’-Q-P diagram and the F n ’-Q-P diagram are obtained through the internal thread grinding cooling test. During adjustment, first adjust the coolant flow rate Q according to the tangential grinding force, and then adjust the cooling hydraulic pressure P according to the normal grinding force, finally achieving the effect that the theoretical grinding force is equal to the measured grinding force.

[0171] The parts not detailed in the present invention belong to the well-known technologies in the art.

Claims

1. An internal thread grinding cooling adjustment method based on grinding force, characterized in that, Including: Measuring a grinding specimen (10) to obtain the dimensions of the grinding specimen; Installing the grinding specimen (10), torque and speed sensor (3), and three-component dynamometer (9) on an internal thread grinding machine; Calibrating the torque and speed sensor (3); Turn on the internal thread grinding machine, complete the tool setting, and set the three-jaw chuck (1) to rotate at a speed of ω v with a feed rate of ap and the grinding wheel rotating at a speed of ω s , turn on the torque speed sensor (3) and the three-component dynamometer (9) and record the data until the recording stops after one feed process is completed; Processing the data of the torque and speed sensor (3) and three-component dynamometer (9) recorded during this feed process to obtain the measured grinding force data during this feed process; Calculating the angle φ through which the grinding wheel grains rotate from entering the grinding zone to leaving the grinding zone; Calculate the dynamic contact arc length l of thread grinding k ; According to the angle φ and the dynamic contact arc length l of thread grinding k , calculate the theoretical tangential grinding force F t ’ and the theoretical normal grinding force F n ’ as the theoretical grinding force; Adjusting the cooling parameters, i.e., the coolant flow rate Q and the cooling hydraulic pressure P, until the theoretical grinding force is equal to the measured grinding force.

2. The internal thread grinding cooling adjustment method based on grinding force according to claim 1, wherein, The said measuring the grinding specimen (10) includes: determining the material of the grinding specimen (10), the inner hole diameter d1, the outer circle diameter d2, the total length l1 of the workpiece, the inner hole depth l2, calculating the total weight G1 of the grinding specimen, and finding the center of gravity position of the grinding specimen (10).

3. A method for adjusting the cooling of internal thread grinding based on grinding force according to claim 2, characterized in that The said installing the grinding specimen (10), torque and speed sensor (3), and three-component dynamometer (9) on an internal thread grinding machine includes: Fixing the three-jaw chuck (1) on the internal thread grinding machine, clamping the bushing (2) with the three jaws on the three-jaw chuck (1), connecting one end of the bushing (2) to the torque and speed sensor (3), connecting the torque and speed sensor (3) to the torque and speed sensor base (4), and fixing the torque and speed sensor base (4) on the internal thread grinding machine; connecting the other end of the torque and speed sensor (3) to the three-component dynamometer base (6), installing the three-component dynamometer base (6) in the bearing hole of the torque and speed sensor base (4) through the bearing (5), and axially positioning the bearing (5) with the snap ring (7) and the bearing baffle (8); connecting the three-component dynamometer (9) to the three-component dynamometer base (6), and connecting the grinding specimen (10) to the three-component dynamometer (9).

4. A method for adjusting the cooling during internal thread grinding based on grinding force according to claim 3, characterized in that The said calibrating the torque and speed sensor (3) includes: Turn on the internal thread grinding machine, turn on the torque and speed sensor (3) and the three-component dynamometer (9) in the stationary state and record the measured data. After standing still for t1 seconds, set the three-jaw chuck (1) to rotate at a speed of ω v Rotate, record the measured data of the torque and speed sensor (3) and the three-component dynamometer (9), and adjust the torque and speed sensor (3) so that the measured data of the torque and speed sensor (3) in the first t1 seconds is 0; Adjusting the three-component dynamometer (9) so that the data of the three-component dynamometer (9) in the x-axis and y-axis directions are respectively: x = G 1x0 sin(ω v t + γ) y = G 1y0 cos(ω v t + γ), Among them, G 1x0 is the initial gravity component of the three-component force sensor (9) in the x-axis direction; G 1y0 is the initial gravity component of the three-component force sensor (9) in the y-axis direction; t is the rotation time; γ is the angle between the initial gravity direction and the x-axis, and tanγ = G 1y0 / G 1x0 .

5. A method for regulating the cooling of internal thread grinding based on grinding force according to claim 4, characterized in that The said processing the data of the torque and speed sensor (3) and three-component dynamometer (9) recorded during this feed process to obtain the measurement data of all grinding forces during this feed process: The tangential force F of high-speed grinding of internal threads during this feed t is as follows: T1 is the reading recorded by the torque and speed sensor (3); Subtract G1sin(ω v t + γ) and G1cos(ω v t + γ) from the time-domain data in the x-axis and y-axis directions of the three-component dynamometer (9) respectively, and perform Fourier transform on the time values corresponding to the curves after subtraction to process the time-domain data into frequency-domain data; According to the rotational speed ω of the grinding wheel s and the diameter d of the grinding wheel used s , the rotational frequency f of the grinding wheel is calculated s , then the values of the frequency-domain data in the x-axis and y-axis directions corresponding to f s are F x and F y respectively; The total grinding force F of high-speed internal thread grinding during this feed process 总 is as follows: According to the total grinding force F for high-speed grinding of internal threads 总 and the tangential force F for high-speed grinding of internal threads t , the normal force F for high-speed grinding of internal threads is calculated n :

6. The internal thread grinding cooling adjustment method based on grinding force according to claim 5, characterized in that, The angle through which the grinding wheel grains rotate from entering the grinding zone to leaving the grinding zone where l φ is the chord length corresponding to the angle φ at the maximum outer circle of the grinding wheel; a is the axial distance between the grinding wheel and the grinding specimen; S φ is the area of the triangle formed by the grinding wheel radius, the grinding specimen radius, and the axial distance between the grinding wheel and the grinding specimen; p is the semi-perimeter of the triangle formed by the grinding wheel radius, the grinding specimen radius, and the axial distance between the grinding wheel and the grinding specimen.

7. A method for regulating the cooling of internal thread grinding based on grinding force according to claim 6, characterized in that, The dynamic contact arc length of the thread grinding where d s is the grinding wheel diameter; v s is the linear velocity of the grinding wheel's rotational motion; v d is the linear velocity of the grinding specimen's linear motion; v w is the linear velocity of the grinding specimen's rotational motion; α is the angle between the axis of the grinding wheel and the axis of the grinding specimen.

8. A method for adjusting the cooling during internal thread grinding based on grinding force according to claim 7, characterized in that, The theoretical tangential grinding force F t ’ and the theoretical normal grinding force F n ’ are as follows: where z0 represents the length of the workpiece in the z-axis direction; Single-layer tangential grinding force F t0 and single-layer normal grinding force F n0 are respectively: Dynamic effective abrasive number N d = l k ·N t , where l k is the dynamic contact arc length of thread grinding, N t is the grit number of the grinding wheel; F p is the unit grinding force; a g is the total grinding depth; θ0 is the half apex angle of a single abrasive grain.

9. A method for adjusting the cooling of internal thread grinding based on grinding force according to claim 8, characterized in that, Also including: Calculating the heat source intensity g; The heat source intensity Among them, the total grinding heat power P 总 is as follows: J q is the mechanical equivalent of heat; The grinding heat ratio R of the incoming grinding specimen w is as follows: where λ is the heat transfer coefficient; ρ is the density; c is the specific heat capacity; S n is the contact area between the grinding wheel and the workpiece during internal thread grinding; The subscript s represents the grinding wheel; the subscript w represents the grinding specimen; the subscript f represents the grinding fluid; where a is the distance between the grinding wheel and the workpiece axis; b is the tangential distance between the contact arc and the workpiece axis; c is the normal distance between the contact arc and the workpiece axis; β is the thread profile angle; V is the volume of metal removed per unit time, Establish the grinding temperature field of the grinding specimen and obtain the maximum temperature T on the surface of the grinding specimen max ; The temperature field distribution of the grinding specimen along the z-axis is: where T is the ambient temperature around the internal thread grinding workpiece; z represents the axial length, and s represents a complex variable; b(t - s, z) is the convective heat transfer coefficient on the surface of the grinding specimen; d(t - s, z) is the surface temperature distribution of the grinding specimen.

10. A method for adjusting the cooling during internal thread grinding based on the grinding force according to claim 9, characterized in that, The said adjusting the cooling parameters, i.e., the coolant flow rate Q and the cooling hydraulic pressure P, until the theoretical grinding force is equal to the measured grinding force, includes: Compare the measured tangential force F of high-speed internal thread grinding t with the theoretical tangential grinding force F t ', the normal force F of high-speed internal thread grinding n with the theoretical normal grinding force F n '. According to the F t '-Q-P diagram and F n '-Q-P diagram, increase or decrease the coolant flow rate Q and coolant pressure P in real time according to the corresponding cooling parameters until the theoretical grinding force is equal to the measured grinding force; During adjustment, first adjust the coolant flow rate Q according to the tangential grinding force, and then adjust the cooling hydraulic pressure P according to the normal grinding force, finally achieving the effect that the theoretical grinding force is equal to the measured grinding force.

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