Lead screw running-in device, running-in method and control method

Abstract

The invention relates to a lead screw running-in device, a running-in method and a control method, the lead screw running-in device comprises a grinding platform, a front mounting seat, a middle mounting seat and a rear mounting seat, the front mounting seat, the middle mounting seat and the rear mounting seat are fixedly arranged on the grinding platform, a pushing electric cylinder is fixedly mounted between the rear mounting seat and the middle mounting seat, and the telescopic end of the pushing electric cylinder is fixedly connected with a connecting part; a driving part is arranged on the front mounting seat, and a running-in jig is arranged at the driving end of the driving part; the front mounting base is fixedly provided with an extension cylinder, and the center lines of the telescopic end of the pushing electric cylinder, the lead screw, the running-in jig and the extension cylinder are located on the same horizontal line; during running-in, the driving part drives the running-in jig to run in the lead screw while the pushing electric cylinder pushes the lead screw to move towards the interior of the extending cylinder; according to the lead screw running-in jig, the running-in working mode is modified, the situation that the running-in precision is damaged due to the fact that the lead screw is subjected to longitudinal pressure in the running-in process is avoided, meanwhile, the concentricity between the lead screw and the running-in jig in the running-in process can be guaranteed in the mode that the lead screw is pushed to conduct running-in, and the running-in precision of the lead screw is improved.

Description

Technical Field

[0001] This application relates to the technical field of screw rod running-in, and specifically relates to a screw rod running-in device, a running-in method, and a control method. Background Art

[0002] Most domestic box-launched missiles use a locking mechanism to fix the missile. Currently, the commonly used locking mechanism mostly adopts a design method in which a screw rod drives the left and right movement of a slider to drive the up and down movement of a bolt. There are multiple moving parts connected in such a structure. Due to the existence of machining errors, it is difficult to ensure the consistency of parts, and phenomena such as jamming and inflexible rotation often occur. The general method is to perform multiple motion running-ins after assembly and adjustment.

[0003] Currently, during running-in, a motor is used to drive a running-in nut to move on the screw rod to achieve running-in of the screw rod. Although this method can achieve running-in of the screw rod, during running-in, since the motor needs to drive the running-in fixture to move on the screw rod to achieve running-in, the screw rod will be subjected to a downward pressure from the running-in fixture during the running-in process, resulting in an increase in longitudinal pressure. The screw rod has a greater load during running-in, leading to the problem of too low precision of the running-in screw rod. At the same time, since the motor drives the fixture to move on the screw rod for running-in, it is impossible to ensure that the concentricity remains consistent during the running-in process, resulting in a decrease in the finished product rate of the screw rod after running-in; at the same time, during the running-in process, it is impossible to use the running-in data to judge whether the screw rod meets the standard after running-in, and independent manual inspection and judgment are required, increasing the cost of running-in processing. Summary of the Invention

[0004] In order to overcome the above-mentioned shortcomings of the prior art, the main purpose of the present invention is to provide a screw rod running-in device, a running-in method, and a control method that can improve the running-in precision and change the running-in method.

[0005] To achieve the above purpose, the present invention adopts the following technical solution. A screw rod running-in device includes a grinding platform, a front mounting seat, a middle mounting seat, and a rear mounting seat fixedly arranged on the grinding platform. A pushing electric cylinder is fixedly installed between the rear mounting seat and the middle mounting seat. The telescopic end of the pushing electric cylinder passes through the middle mounting seat and is fixedly connected to a connecting portion provided between the front mounting seat and the middle mounting seat; a driving portion is fixedly installed on the front mounting seat, and a running-in fixture is provided at the driving end of the driving portion; An extension cylinder is fixedly provided at the end of the front mounting seat away from the middle mounting seat, and the end of the extension cylinder passes through the front mounting seat and faces the connecting portion; One end of the screw rod to be run-in is fixedly connected to the connecting portion, and the other end passes through the running-in fixture and extends into the extension cylinder and makes a non-destructive sliding contact with the inner wall of the extension cylinder; and the center lines of the telescopic end of the pushing electric cylinder, the screw rod, the running-in fixture, and the extension cylinder are located on the same horizontal line; During the running-in process, the driving electric cylinder pushes the lead screw into the extension tube, while the driving unit drives the running-in fixture to run-in the lead screw.

[0006] Preferably, the running-in jig includes a first retaining ring fixedly connected to the driving end of the driving part, a second retaining ring connected to the first retaining ring, an inner connecting ring fixedly installed inside the first retaining ring, a buckle is provided on the axial surface of the first retaining ring, a seat matching with the buckle is provided on the axial surface of the second retaining ring, a copper sleeve is provided inside the second retaining ring, and also includes a running-in nut for running-in the screw rod, after the first retaining ring and the second retaining ring are fixedly connected by the buckle and the seat, the copper sleeve and the inner connecting ring complete the fixing and limiting of the running-in nut; wherein the inner connecting ring is provided with a plurality of limiting holes, and the second retaining ring is provided with a limiting pin matching with the limiting holes.

[0007] Preferably, the front mounting seat and the middle mounting seat are fixedly connected via two positioning shafts, a connecting plate is provided between the front mounting seat and the middle mounting seat, the two positioning shafts pass through both ends of the connecting plate and are slidably connected to the connecting plate, the telescopic end of the pushing electric cylinder is fixedly connected to the connecting plate, and the connecting part is fixedly connected to the connecting plate.

[0008] Preferably, a center rod is fixedly connected to the connecting part, a screw rod is sleeved on the center rod, and a slider is fixedly connected to the end of the center rod away from the connecting part. The slider is fixedly connected to the end of the center rod by a screw, and the slider is slidably connected to the inside of the extension tube, and a step protrusion is provided on the end of the slider and is inserted into the center hole of the screw rod.

[0009] Preferably, the connecting portion includes a connecting piece connected to the screw rod and a locking piece fixedly connected to the connecting plate, and the connecting piece is fixedly connected to the connecting plate via the locking piece.

[0010] Preferably, the grinding platform is also provided with a front protective cover buckled outside the front mounting seat and a rear protective cover buckled outside the rear mounting seat; the grinding platform is also provided with parallel slide rails, a middle protective cover buckled outside the middle mounting seat, and the two sides of the middle protective cover are respectively slidably connected to the slide rails.

[0011] Preferably, the grinding platform is provided with a process mandrel for correcting the concentricity of the driving electric cylinder, the running-in fixture and the extension cylinder, and the radius of the process mandrel is the same as the radius of the screw rod.

[0012] A screw rod running-in method uses a screw rod running-in device to run-in a screw rod to be run-in, comprising: Step 1, pass the process mandrel on the center rod, and then fix the connecting piece on one end of the center rod; Step 2, pass the process mandrel through the running-in fixture, and fix the slider to the other end of the center rod to complete the limit fixation of the process mandrel; Step 3: Fix the connecting piece at one end of the process mandrel with limited position to the connecting plate fixedly connected by the locking piece, and insert the slider into the extension cylinder. Step 4: Adjust the concentricity of the pushing electric cylinder, the process mandrel, the running-in jig and the extension cylinder. When the center lines of the pushing electric cylinder, the process mandrel, the running-in jig and the extension cylinder are on the same straight line, the adjustment of concentricity is completed. Step 5: Remove the process mandrel from the screw rod running-in device. After fixing the screw rod to be run in at the position of the original process mandrel, start the pushing electric cylinder and the driving part to run in the screw rod to be run in.

[0013] Furthermore, in order to achieve automatic control and use the running-in parameters of the screw rod during the running-in process to judge the quality of the screw rod after running-in, a control method for a screw rod running-in device includes: Start the screw rod running-in device and input the product information of the screw rod to be run in. Input the initial running-in parameter values and input the number of running-in times for pre-running-in. Obtain the running data of the screw rod running-in device during the pre-running-in process. The running data includes current value, voltage value, tensile force value, pressure value, vibration value, single reciprocating time and movement speed. Preprocess the running data during the pre-running-in process, perform discrete distribution analysis on the preprocessed running data, and use the current value, voltage value and vibration value obtained after the discrete distribution analysis as the running-in parameters of the screw rod running-in device. Input the obtained running-in parameters into the running-in device, use the running-in parameters to run in the screw rod to be run in, obtain the running data during the running-in process, and use the signal-to-noise ratio of the current-force ratio in the running data to judge whether there is an abnormality in the running-in device. If there is an abnormality, repair the running-in device; if there is no problem, continue to use the running-in device to run in the screw rod. Use the running data after the screw rod running-in is completed for multi-parameter fusion, and use the multi-parameter fusion result to judge whether the running-in screw rod is qualified.

[0014] The method of the multi-parameter fusion includes: Calculate the information entropy using each running-in parameter at each moment during the running-in process, perform weight allocation using the information entropy obtained from each running-in parameter, and obtain the weight of each running-in parameter. Weight the corresponding running-in parameter and parameter mean using the weight of each running-in parameter. And use the weighted running-in parameters to form a covariance matrix, and obtain the Mahalanobis distance according to the running-in parameters and parameter mean in the covariance matrix. Use the obtained Mahalanobis distance to judge whether there is an abnormality in the running-in screw rod.

[0015] Compared with the prior art, the present invention has the following advantages: 1. The running-in fixture is arranged at one end of the running-in platform. During running-in, the lead screw is moved by pushing the electric cylinder. During the movement, the running-in of the lead screw is completed through the running-in fixture. The working mode is modified, and the moving running-in fixture is modified into a fixed running-in fixture, avoiding the damage of the running-in accuracy caused by the longitudinal pressure during the running-in of the lead screw. At the same time, the method of running-in by pushing the lead screw can ensure the concentricity between the lead screw and the running-in fixture during the running-in process, improving the running-in accuracy of the lead screw; 2. Before running-in, the present invention uses a process mandrel for calibration, ensuring the concentricity between the lead screw and the running-in fixture during the running-in of the lead screw, avoiding the adjustment of the concentricity during the running-in process, and reducing the running-in efficiency; 3. During the running-in process, the quality of the lead screw after running-in is judged by using the parameters during the running-in process, reducing the running-in cost of the whole running-in. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a schematic structural diagram of a lead screw running-in device according to an embodiment of the present invention; Figure 2 is a schematic structural diagram of a lead screw running-in device according to another embodiment of the present invention; Figure 3 is a schematic connection structure diagram of the running-in fixture in the embodiment of the present invention; Figure 4 is a schematic top view structure diagram of the lead screw running-in device in the embodiment of the present invention; Figure 5 is an overall axial view of the lead screw running-in device in the embodiment of the present invention; Figure 6 is a schematic cross-sectional structure diagram of the running-in fixture in the embodiment of the present invention; Figure 7 is a schematic cross-sectional structure diagram of the connecting part in the embodiment of the present invention; Figure 8 is a flowchart of the control method in the embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0017] The present invention will be further described below in conjunction with the drawings and embodiments. Embodiment

[0018] As Figure 1 and Figure 2 shown, this embodiment provides a lead screw running-in device, including a grinding platform 1, a front mounting seat 2, a middle mounting seat 3, and a rear mounting seat 4 fixedly arranged on the grinding platform 1. As Figure 1As shown in the figure, the front mounting base 2, the middle mounting base 3, and the rear mounting base 4 in this embodiment are fixedly installed on the grinding platform 1 in sequence from right to left. Specifically, a plurality of uniformly arranged mounting holes are provided on the grinding platform 1. During installation, the front mounting base 2, the middle mounting base 3, and the rear mounting base 4 are fixed in the corresponding mounting holes according to the required dimensions, and then fixed installation is completed through screws. At the same time, after the installation is completed, the centers of the front mounting base 2, the middle mounting base 3, and the rear mounting base 4 are on the same horizontal line.

[0019] A push cylinder 9 is fixedly installed between the rear mounting base 4 and the middle mounting base 3. Specifically, the cylinder base of the push cylinder 9 is fixedly installed on the rear mounting base 4 through bolts, and the cylinder at the front end of the push cylinder 9 is fixedly connected to the middle mounting base 3, and it is ensured that the telescopic end of the push cylinder 9 can pass through the middle mounting base 3 and extend towards the end of the front mounting base 2; and it is fixedly installed with the connecting part between the middle mounting base 3 and the front mounting base 2.

[0020] In one embodiment, as Figure 4 shown, the middle mounting base 3 and the front mounting base 2 are fixedly connected by two positioning shafts 10. The surface of the positioning shaft 10 is smoothed to reduce friction. A connecting plate 15 is connected to the two positioning shafts 10. Specifically, two through holes penetrating the connecting plate 15 are provided on the left and right sides (or front and rear sides) of the connecting plate 15. Two copper sleeves made of brass are inlaid in the through holes, and the positioning shafts 10 are passed through the copper sleeves to slidably connect the connecting plate 15 with the positioning shafts 10, ensuring that the connecting plate 15 can move on the positioning shafts 10; at the same time, the telescopic end of the push cylinder 9 is fixedly connected to the connecting plate 15, which can ensure that the push cylinder 9 can drive the connecting plate 15 to move left and right (that is, the connecting plate 15 reciprocates between the front mounting base 2 and the rear mounting base 4), and the connecting part 8 is fixedly installed on the connecting plate 15. Specifically, it is fixedly installed in the middle of the connecting plate 15 to ensure that the connecting plate 15 drives the connecting part 8 to move during the movement process.

[0021] A connecting plate 15 is provided between the front mounting base 2 and the middle mounting base 3. Two positioning shafts 10 pass through both ends of the connecting plate 15 and are slidably connected to the connecting plate 15. The telescopic end of the push cylinder 9 passes through the connecting plate 15 and is fixedly connected to the connecting part 8.

[0022] An extension cylinder 12 is fixedly provided at the end of the front mounting base 2 far from the middle mounting base 3, and the end of the extension cylinder 12 passes through the front mounting base 2 and faces the connecting part 8; specifically, a through hole is provided on the front mounting base 2, and the end of the extension cylinder 12 is inserted into the through hole to complete the installation of the extension cylinder 12, ensuring that during work, the polished lead screw will enter the extension cylinder 12.

[0023] A running-in fixture 6 is provided on the front mounting base 2. The running-in fixture 6 is mainly used to perform running-in on the lead screw 13 to be run in. Specifically, the running-in fixture 6 is installed at the end close to the middle mounting base 3, and the lead screw 13 of the running-in fixture 6 can enter the extension cylinder 12. At the same time, a driving part 5 is provided on the front mounting base 2, and the driving part 5 is used to drive the running-in fixture 6 to perform running-in on the lead screw 13 to be run in; Specifically, when performing running-in, one end of the lead screw 13 to be run in is fixedly connected to the connecting part 8, and the other end of the lead screw 13 passes through the running-in fixture 6 and enters the extension cylinder 12. At this time, it is necessary to ensure that the center lines of the telescopic end of the pushing electric cylinder 9, the lead screw 13, the running-in fixture 6 and the extension cylinder 12 are on the same horizontal line to improve the concentricity of the lead screw 13, the running-in fixture 6 and the extension cylinder 12; that is, to ensure that when the pushing electric cylinder 9 pushes the lead screw 13 and the lead screw 13 is run in through the running-in fixture 6, it is ensured that the lead screw 13 can achieve a complete linear motion, and the accuracy of the lead screw 13 during running-in is improved.

[0024] In one embodiment, such as Figure 3 and Figure 6The running-in jig 6 includes a first snap ring 601 fixedly connected to the driving end of the driving part 5. The first snap ring 601 is fixedly connected to the driving end of the driving part 5, which can ensure that the driving part 5 drives the first snap ring 601 to rotate. Specifically, the driving part 5 includes at least one driving motor, and a driving gear is fixedly arranged on the driving shaft of the driving motor. A driven gear meshing with the driving gear is sleeved outside the first snap ring 601. Thus, the driving motor can drive the first snap ring 601 to rotate, that is, drive the first snap ring 601 to rotate along the verification center line. A second snap ring 7 is also fixedly connected to the first snap ring 601. The center of the second snap ring 7 is concentric with the center of the first snap ring 601. When the first snap ring 601 rotates, it can drive the second snap ring 7 to rotate (i.e., the second snap ring 7 can rotate around the center line); An inner connecting ring 602 is fixedly embedded in the first snap ring 601, and a running-in nut 603 for running in the lead screw 13 is embedded in the inner connecting ring 602. During running-in, the running-in nut 603 can drive the first snap ring 601 and the inner connecting ring 602 to rotate through the driving motor to achieve the purpose of running in the lead screw 13 to be run in; At the same time, in order to ensure that the running-in nut 603 does not rotate during the running-in of the lead screw 13, a clamping seat 701 is arranged on the axial surface of the second snap ring 7, and a copper sleeve 702 is arranged at the center of the second snap ring 7. During running-in, the copper sleeve 702 is sleeved outside the lead screw 13. When the clamping seat 701 is fixedly connected to a buckle 605 fixedly arranged on the axial surface of the first snap ring 601, the copper sleeve 702 is sleeved on the lead screw nut 603 to limit the lead screw nut 603, avoiding the situation of slipping of the lead screw nut 603 during running-in. The lead screw nut 603 is fixed and limited through the copper sleeve 702 and the inner connecting ring 602; In one embodiment, a through hole is arranged on the clamping seat 701. The clamping seat 701 is inserted into the buckle 605, and then the clamping seat 701 and the buckle 605 are fixedly connected through a pin to realize the fixed connection between the first snap ring 601 and the second snap ring 7. In another embodiment, in order to facilitate alignment, a circle of limiting holes 604 is evenly arranged on the inner connecting ring 602, and a limiting pin is arranged on the end surface of the second snap ring 7 facing the first snap ring 601. During connection, the limiting pin can be directly inserted into the limiting holes 604 for limiting. During the limiting process, the limiting pin can be inserted into any one of the limiting holes 604 to achieve the purpose of limiting, avoiding the need to rotate the second snap ring 7 to achieve fixed limiting.

[0025] In another embodiment, to ensure that the lead screw 13 can perform an absolute linear motion during the running-in process and the force it receives is minimized when being pushed by the push cylinder 9, a central rod 19 is fixedly connected to the connecting portion 8. The lead screw 13 is sleeved on the central rod 19. A slider 20 is fixedly connected to the end of the central rod 19 away from the connecting portion 8. The slider 20 is fixedly connected to the end of the central rod 19 by screws 21, and the slider 20 is slidably connected to the inside of the extension cylinder 12. A stepped protrusion provided at the end of the slider 20 is inserted into the central hole of the lead screw 13. The slider 20 is made of brass material, which can slide in the extension cylinder 12 with less friction. At the same time, due to the presence of the slider 20, the path of the lead screw 13 during the running-in process can be effectively limited, providing a conditional path for achieving linear motion. Specifically, when the slider 20 is installed, it is fixed to the end of the central rod 19 by screws. The diameter of the slider 20 is larger than that of the lead screw 13, and the lead screw 13 is sleeved on the central rod 19. Therefore, the connection between the lead screw and the central rod 19 is completed through the limit of the slider 20. Further, a stepped conical surface is provided at the end of the slider 20, and this conical surface can be inserted into the through hole of the lead screw 13. The lead screw 13 is fixed by the extrusion installation between the slider and the connecting portion, reducing damage to the lead screw 13.

[0026] In one embodiment, as Figure 7 shown, the connecting portion 8 includes a connecting member 801 connected to the lead screw 13 and a locking member 802 fixedly connected to the connecting plate 15. The connecting member 801 is fixedly connected to the connecting plate 15 through the locking member 802. The connecting member 801 in this example is made of yellowish-brown copper material. Specifically, when connecting, the end of the central rod 19 sleeved with the lead screw 13 is inserted into the connecting member for fixed connection. At the same time, the end of the connecting member is inserted into the through hole of the lead screw 13. The lead screw 13 is squeezed and fixed on the central rod 19 by the connecting member 801 and the slider 20. After the lead screw 13 is fixed, the connecting member 801 and the locking member 802 are fixedly connected to complete the connection between the connecting plate 15 and the lead screw 13.

[0027] In another embodiment, a front protective cover 16 buckled outside the front mounting seat 2 and a rear protective cover 18 buckled outside the rear mounting seat 3 are further provided on the grinding platform 1. Heat dissipation holes are provided at the positions of the front protective cover 16 and the rear protective cover 18 corresponding to the driving portion and the push cylinder for dissipating heat from the driving motor and the push cylinder in the driving portion. The front protective cover 16 and the protective cover 18 are fixedly connected to the grinding platform 1 to achieve the protection effect on the entire grinding platform. At the same time, as Figure 5The grinding platform 1 is also provided with mutually parallel slide rails 14, a middle protective cover 17 buckled on the outside of the middle mounting seat 3, and the two sides of the middle protective cover 17 are respectively slidably connected with the slide rails 14. The middle protective cover 17 mainly protects the operation section of the screw rod running-in process. When operation is required, the middle protective cover 17 is pushed away from the operation section to perform the operation. When the operation is completed and the running-in is required, the middle protective cover is pulled back to the operation section to avoid accidents in the running-in process that may cause damage to the personal safety of the operator.

[0028] In one embodiment, in order to improve the concentricity and complete the calibration before grinding, and avoid the concentricity adjustment during the running-in process, a process mandrel 11 for calibrating the concentricity of the push cylinder 9, the running-in fixture 6 and the extension cylinder 12 is provided on the grinding platform 1, and the radius of the process mandrel 11 is the same as the radius of the screw 13. The concentricity is calibrated before running-in using the process mandrel 11, which improves the running-in efficiency.

[0029] Example 2 A screw rod running-in method, using the screw rod running-in device provided in Example 1 to run-in a screw rod 13 to be run-in, comprises: Step 1, pass the process mandrel 11 on the center rod 19, and then fix the connecting piece 801 to one end of the center rod 19; the process mandrel 11 in this embodiment has the same size and model as the screw rod 13 to be run-in, and the process mandrel 11 is used to check the concentricity in the running-in device before running-in, and the running-in of the screw rod is carried out after the check is completed; when the process mandrel 11 is connected to the connecting piece 801, the connection method of the screw rod and the connecting piece 801 is the same, that is, the end of the connecting piece 801 is inserted into the through hole of the process mandrel 11; Step 2, pass the process mandrel 11 through the running-in fixture 6, and fix the slider 20 to the other end of the center rod 19 to complete the limit fixation of the process mandrel 11; at this time, the process mandrel 11 is pressed and installed on the center rod 19 through the joint action of the slider 20 and the connecting piece 801; Step 3, after the limited installation is completed, the connecting piece 801 at one end of the process mandrel 11 is fixedly connected to the connecting plate 15 through the locking piece 802, and the slider 20 is inserted into the extension tube 12; the installation of the process mandrel 11 is completed; Step 4, after completing the installation of the process mandrel 11, the operator adjusts the concentricity of the push cylinder 9, the process mandrel 11, the running-in fixture 6 and the extension tube 12. When the center lines of the push cylinder 9, the process mandrel 11, the running-in fixture 6 and the extension tube 12 are located on the same straight line, the concentricity adjustment is completed; Step 5: Remove the process mandrel 11 from the lead screw running-in device. When disassembling, remove the slider 20 from the center rod 19, then withdraw the process mandrel 11 from the center rod 19. Next, thread the lead screw 13 to be run-in onto the center rod 19. Finally, fix the slider 20 onto the center rod 19 to complete the extrusion and fixation installation of the lead screw 13. Finally, start the push electric cylinder 9 and the drive unit 5 to run in the lead screw 13 to be run-in. In this embodiment, the push electric cylinder 9 and the drive motor in the drive unit 5 are controlled by background software, and the power supply can use municipal electricity.

[0030] Embodiment 3 As Figure 8 shown, this embodiment provides a control method for a lead screw running-in device, including: S1. Start the lead screw running-in device and enter the product information of the lead screw to be run-in; the information of the lead screw to be run-in includes the product model of the lead screw 13 for product matching. When the product information of the lead screw to be run-in exists in the ground detection software, there is no need to enter it, and it can be directly selected. When there is no product information in the software, enter the product model of the lead screw 13; After completing the entry of the product model, select the corresponding initial running-in parameter values according to the product model, and use these initial parameters to pre-run in the lead screw 13. In this embodiment, the number of pre-running-in times is not less than 30 times; the initial parameters in this embodiment are current value, voltage value, vibration value, etc.; S2. Obtain the running data of the lead screw running-in device during the pre-running-in process. The running data includes current value, voltage value, tensile force value, pressure value, vibration value, single reciprocating time, and movement speed; Preprocess the running data during the pre-running-in process. In this embodiment, the preprocessing includes first performing primary denoising on the collected data. The denoising method is to use the Nyquist sampling theorem for processing. For example, for vibration signals and current signals, if the frequency range of the vibration signal is 0 - 500Hz, then the sampling frequency during sampling is greater than 1kHz; perform primary denoising (i.e., screening) on the collected data according to this scheme.

[0031] Process the screened running data using a noise filtering method. In this embodiment, the noise filtering method is the Kalman filter. Using the Kalman filter can eliminate high-frequency noise. Since the Kalman filter method is a conventional denoising method in this technical field, the detailed process of it will not be described in detail in this embodiment; S3. Perform a discrete distribution analysis on the preprocessed operation data. In this embodiment, the discrete analysis method uses Kernel Density Estimation (KDE) to replace the traditional histogram method to improve the flexibility of interval division and the degree of information retention. The kernel density estimation method in this embodiment is as follows:

[0032] where K is the Gaussian kernel function, , h is the bandwidth, calculated according to the Silverman criterion:

[0033] Distribution feature extraction: Calculate skewness and kurtosis to identify the data distribution type:

[0034] Measure the distribution symmetry (positive skew indicates a long right tail, and negative skew indicates a long left tail);

[0035] Measure the thickness of the distribution tail (relative to the normal distribution); 3 indicates a normal distribution, >3 indicates a leptokurtic and heavy-tailed distribution, and <3 indicates a platykurtic and thin-tailed distribution; where: : Estimated probability density function value; n: Number of samples (the amount of data after preprocessing. If a discrete distribution analysis is performed on the preprocessed current values, then this data volume is the number of all preprocessed current values); g: Normalization constant (usually 1); X i : The i-th sample point (the i-th data after preprocessing); h: Bandwidth (controlling the degree of smoothing); : Kernel function (here it is the Gaussian kernel: ); : Expected value; X: Random variable; : Mean value (the mean value of the preprocessed data, such as the mean value of the current values); : Standard deviation (such as the standard deviation of the current values).

[0036] S4. Take the current value, voltage value, and vibration value obtained after discrete distribution analysis as the running-in parameters of the lead screw running-in device; the data collected after pre-running-in is processed as new running-in parameters to improve the authenticity of running-in. S5. Input the obtained running-in parameters into the running-in device, use these running-in parameters to run-in the lead screw to be run-in, obtain the operating data during running-in, and use the signal-to-noise ratio of the current-force ratio in the operating data; the signal-to-noise ratio of the current-force ratio in this embodiment is determined using the signal-to-noise ratio (SNR) concept in the Taguchi method. The specific method is as follows:

[0037] Coefficient of variation threshold setting: Based on the central limit theorem, the sample mean distribution approaches a normal distribution. Set the two-sided confidence interval: SNR : Signal-to-noise ratio (the larger the value, the better the proportion stability); n: Number of samples; (the number of current values or force values in the operating data collected during running-in; the number of current values and force values corresponds one by one); I i : The i-th current value; F i : The i-th force value; : Maximum allowable coefficient of variation; : Two-sided quantile of the standard normal distribution (such as =0.05 corresponds to (Z = 1.96)); : Population standard deviation; : Population mean; Use the obtained signal-to-noise ratio to determine whether there is an abnormality in the running-in device. If there is an abnormality, repair the running-in device; if there is no problem, continue to use this running-in device to run-in the lead screw. In this embodiment, when making a judgment, compare the obtained signal-to-noise ratio of the current-force ratio with the set threshold of the signal-to-noise ratio of the current-force ratio. When the obtained signal-to-noise ratio of the current-force ratio is greater than or equal to the threshold, it indicates that the equipment is running smoothly, and the device can continue to be used for running-in work. When the obtained signal-to-noise ratio of the current-force ratio is less than the threshold, it indicates that the running stability of the equipment is relatively poor, and there is an abnormality in the running-in device, then it is necessary to stop the machine to repair the running-in device.

[0038] S6. Use the operating data after the lead screw running-in is completed for multi-parameter fusion, and use the multi-parameter fusion result to judge whether the run-in lead screw is qualified.

[0039] The multi-parameter fusion method in this embodiment includes: S601. Calculate the information entropy using each running-in parameter at each moment during the running-in process, and perform weight allocation using the information entropy obtained from each running-in parameter to obtain the weight of each running-in parameter; Specifically, during the running-in process, obtain the operation data every minute, extract the corresponding running-in parameters from the operation data to obtain each running-in parameter data set of each lead screw during the running-in process, and calculate the information entropy using each running-in parameter data set. The calculation method is as follows: First, perform normalization processing on each parameter data in the running-in parameter set to obtain the normalized value; Calculate the information entropy according to the following formula:

[0040] In the formula: : The information entropy of the jth running-in parameter; : The normalized value of the ith sample in the jth running-in parameter set; : Natural logarithm; n is the number of parameters in the running-in parameter set; Calculate the weight using the information entropy of each parameter. The calculation method is as follows:

[0041] Calculate the weight of each parameter using this method; S602. Weight the corresponding running-in parameter and parameter mean using the weight of each running-in parameter; When implementing this embodiment, weight each running-in parameter in the corresponding running-in parameter set using the weight of each parameter to obtain the weighted running-in parameter data set; At the same time, weight the mean of the running-in parameter data set before weighting to obtain the weighted parameter mean; Complete the weighting of each parameter's running-in parameter data set and the weighting of the parameter mean; S603. And use the weighted running-in parameters to form a covariance matrix, and obtain the Mahalanobis distance according to the running-in parameters and parameter mean in the covariance matrix; When constructing the covariance matrix in this embodiment, use each parameter's weighted running-in parameter data set for construction, and then calculate the Mahalanobis distance using the constructed covariance matrix and the weighted parameter mean. The formula for the Mahalanobis distance used in this embodiment is as follows:

[0042] In the formula: D represents the Mahalanobis distance; X is the sample vector in the covariance matrix; u: represents the mean vector in the covariance matrix; represents the covariance matrix; T represents the transpose.

[0043] S604. Determine whether there is an abnormality in the running-in lead screw by using the obtained Mahalanobis distance. Specifically, compare the obtained Mahalanobis distance with the set threshold. When the Mahalanobis distance is greater than the set threshold, it indicates that there is a problem with the parameters during the running-in process, which means there is a problem with the lead screw after running-in, and it is determined that the lead screw does not meet the quality requirements. When the calculated Mahalanobis distance is less than or equal to the set threshold, it is determined that the parameters remain stable during the running-in process, indicating that the quality of the running-in lead screw meets the requirements under the condition of maintaining such stable parameters. This embodiment uses real-time acquisition of parameter changes (parameters in the running data) during the running-in process, and uses the parameter changes to measure the running-in quality of the lead screw, avoiding the need for manual inspection of the lead screw after running-in and reducing the running-in cost of the lead screw.

[0044] The above embodiments are only examples of the present invention and do not constitute a limitation on the protection scope of the present invention. Any design identical or similar to the present invention falls within the protection scope of the present invention.

Claims

1. A lead screw running-in device, comprising a grinding platform (1), a front mounting seat (2), a middle mounting seat (3) and a rear mounting seat (4) fixedly arranged on the grinding platform (1), characterized in that, A push cylinder (9) is fixedly installed between the rear mounting seat (4) and the middle mounting seat (3). The telescopic end of the push cylinder (9) passes through the middle mounting seat (3) and is fixedly connected to a connecting part (8) provided between the front mounting seat (2) and the middle mounting seat (3); A driving part (5) is fixedly installed on the front mounting seat (2), and a running-in fixture (6) is provided at the driving end of the driving part (5); An extension cylinder (12) is fixedly provided at the end of the front mounting seat (2) away from the middle mounting seat (3), and the end of the extension cylinder (12) passes through the front mounting seat (2) and faces the connecting part (8); One end of the lead screw (13) to be run-in is fixedly connected to the connecting part (8), and the other end passes through the running-in fixture (6) and extends into the extension cylinder (12) and makes non-destructive sliding contact with the inner wall of the extension cylinder (12); And the center lines of the telescopic end of the push cylinder (9), the lead screw (13), the running-in fixture (6) and the extension cylinder (12) are located on the same horizontal line; During running-in, while the push cylinder (9) pushes the lead screw (13) to move into the extension cylinder (12), the driving part (5) drives the running-in fixture (6) to run-in the lead screw (13).

2. The lead screw running-in device according to claim 1, characterized in that, The running-in fixture (6) includes a first clamping ring (601) fixedly connected to the driving end of the driving part (5), a second clamping ring (7) connected to the first clamping ring (601), an inner connecting ring (602) fixedly installed in the first clamping ring (601), a buckle (605) provided on the axial surface of the first clamping ring (601), a clamping seat (701) provided on the axial surface of the second clamping ring (7) and cooperating with the buckle (605), a copper sleeve (702) provided in the second clamping ring (7), and a running-in nut (603) for running-in the lead screw (13). After the first clamping ring (601) and the second clamping ring (7) are fixedly connected through the buckle (605) and the clamping seat (701), the copper sleeve (702) and the inner connecting ring (602) complete the fixation and limitation of the running-in nut (603); Among them, a plurality of limiting holes (604) are provided on the inner connecting ring (602), and limiting pins cooperating with the limiting holes (604) are provided on the second clamping ring (7).

3. The lead screw running-in device according to claim 1, characterized in that, The front mounting seat (2) and the middle mounting seat (3) are fixedly connected through two positioning shafts (10). A connecting plate (15) is provided between the front mounting seat (2) and the middle mounting seat (3). The two positioning shafts (10) pass through both ends of the connecting plate (15) and are slidably connected to the connecting plate (15). The telescopic end of the push cylinder (9) is fixedly connected to the connecting plate (15), and the connecting part (8) is fixedly connected to the connecting plate (15).

4. The lead screw running-in device according to claim 1, characterized in that, The connecting portion (8) is fixedly connected to a center rod (19), the screw rod (13) is sleeved on the center rod (19), and the end of the center rod (19) away from the connecting portion (8) is fixedly connected to a slider (20), the slider (20) is fixedly connected to the end of the center rod (19) by a screw (21), and the slider (20) is slidably connected to the inside of the extension tube (12), and a step protrusion provided on the end of the slider (20) is inserted into the center hole of the screw rod (13).

5. The lead screw running-in device according to claim 3, characterized in that, The connecting portion (8) comprises a connecting piece (801) connected to the screw rod (13), and a locking piece (802) fixedly connected to the connecting plate (15); the connecting piece (801) is fixedly connected to the connecting plate (15) via the locking piece (802).

6. The lead screw running-in device according to claim 1, wherein The grinding platform (1) is also provided with a front protective cover (16) buckled outside the front mounting seat (2) and a rear protective cover (18) buckled outside the rear mounting seat (4); the grinding platform (1) is also provided with mutually parallel slide rails (14), a middle protective cover (17) buckled outside the middle mounting seat (3), and two sides of the middle protective cover (17) are respectively slidably connected to the slide rails (14).

7. The lead screw running-in device according to claim 1, characterized in that, The grinding platform (1) is provided with a process mandrel (11) for calibrating the concentricity of the driving electric cylinder (9), the running-in fixture (6) and the extension cylinder (12), and the radius of the process mandrel (11) is the same as the radius of the screw rod (13).

8. A lead screw running-in method, characterized in that, Using any one of the screw running-in devices of claims 1 to 7 to run-in a screw (13) to be run-in, comprising: Step 1, insert the process mandrel (11) onto the center rod (19), and then fix the connector (801) onto one end of the center rod (19); Step 2, passing the process mandrel (11) through the running-in fixture (6), and fixing the slider (20) to the other end of the center rod (19), thereby completing the limiting fixation of the process mandrel (11); Step 3, inserting the connecting piece (801) at one end of the process mandrel (11) that has completed the limiting into the connecting plate (15) fixedly connected by the locking piece (802), and the sliding block (20) into the extension tube (12); Step 4, adjusting the concentricity of the push electric cylinder (9), the process mandrel (11), the running-in fixture (6) and the extension tube (12), and when the center lines of the push electric cylinder (9), the process mandrel (11), the running-in fixture (6) and the extension tube (12) are located on the same straight line, the concentricity adjustment is completed; Step 5, remove the process mandrel (11) from the screw running-in device, fix the screw (13) to be run-in at the position of the original process mandrel (11), and then start the push electric cylinder (9) and the drive unit (5) to run-in the screw (13) to be run-in.

9. A control method for a lead screw running-in device, characterized in that, include: Start the screw running-in device and enter the product information of the screw to be run-in; Enter the initial running-in parameter values ​​and the number of running-in times for pre-running; Obtaining the operating data of the screw running-in device during the pre-running-in process, the operating data including current value, voltage value, tension value, pressure value, vibration value, single reciprocating time and movement speed; Preprocess the operation data during the pre - running - in process, and perform discrete distribution analysis on the preprocessed operation data. Take the current value, voltage value, and vibration value obtained from the discrete distribution analysis as the running - in parameters of the lead - screw running - in device; Input the obtained running - in parameters into the running - in device, use these running - in parameters to run - in the lead - screw to be run - in, obtain the operation data during running - in, and use the signal - to - noise ratio of the current - force ratio in the operation data. Use the obtained signal - to - noise ratio to judge whether there is an abnormality in the running - in device. If there is an abnormality, repair the running - in device; If there is no problem, continue to use this running - in device to run - in the lead - screw; Use the operation data after the lead - screw running - in is completed for multi - parameter fusion, and use the multi - parameter fusion result to judge whether the run - in lead - screw is qualified.

10. The control method of a lead screw running-in device according to claim 9, characterized in that, The method of the multi - parameter fusion includes: Calculate the information entropy using each running - in parameter at each moment during the running - in process, perform weight assignment using the information entropy obtained from each running - in parameter, and obtain the weight of each running - in parameter; Weight the corresponding running - in parameter and parameter mean using the weight of each running - in parameter; Construct a covariance matrix using the weighted running - in parameters, and obtain the Mahalanobis distance according to the running - in parameters and parameter mean in the covariance matrix; Use the obtained Mahalanobis distance to judge whether there is an abnormality in the run - in lead - screw.

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