Gear tooth surface uniformization abrasive grain flow polishing device and method

Abstract

The application provides a gear tooth surface uniformization abrasive flow polishing device and method. The method is characterized in that tooth-shaped flow guide pieces in the same shape as the gear are installed at the upper and lower ends of the gear, a flow guide section design is introduced, an abrasive flow medium path flow channel model is constructed, a Latin hypercube sampling method is used to sample and group the main parameters affecting the experiment, abrasive flow polishing simulation is performed in groups, a Gaussian regression process is used to select the minimum root mean square error of the PiVi data of each group, the experimental parameters of the group are determined, a group of optimal inlet pressure, back pressure and flow guide section length abrasive flow processing parameters are obtained, and finally the method is used to guide the experiment. The method reduces the influence of the inlet effect, constructs an abrasive flow medium path flow channel model, obtains a group of optimal abrasive flow processing parameter combinations, is suitable for straight gears and helical gears, and has strong universality.

Description

Technical Field

[0001] This invention relates to the field of ultra-precision machining technology, and in particular to an abrasive flow polishing device and method for uniformizing gear tooth surfaces. Background Technology

[0002] Gears, as core components of mechanical transmission systems, are widely used in key fields such as aerospace, new energy, and transportation. The quality of their tooth surfaces directly affects the noise level, service life, and transmission efficiency of equipment. With the increasingly urgent demand for high-speed and high-precision gears in industrial development, the requirements for tooth surface quality are becoming increasingly stringent.

[0003] Abrasive flow polishing technology, with its advantages of uniform micro-cutting of complex curved surfaces, high processing efficiency, and lack of limitations due to material and structure, is considered to have great potential for improving gear tooth surface quality. However, when this technology is actually applied to gear polishing, its effects show significant shortcomings:

[0004] A. Due to the influence of abrasive particle size distribution, hydrodynamic characteristics and gear geometry, the machining process is prone to the coexistence of "underpolishing" and "overpolishing", resulting in inconsistent material removal, large fluctuations in tooth surface roughness and profile accuracy, and poor tooth surface uniformity.

[0005] B. Lack of universal process specifications and insufficient process versatility make it difficult to consistently meet the dimensional and shape tolerance requirements of high-precision gears;

[0006] C. The high difficulty in controlling process parameters exacerbates quality fluctuations and restricts its application in scenarios with stringent precision requirements.

[0007] Therefore, there is an urgent need to propose an abrasive flow polishing device and method for uniformizing gear tooth surfaces. Summary of the Invention

[0008] The purpose of this invention is to provide an abrasive flow polishing method for uniformizing gear tooth surfaces, in order to solve the problems existing in the prior art.

[0009] The technical solution adopted to achieve the purpose of this invention is as follows: an abrasive flow polishing device for uniformizing gear tooth surfaces, comprising a clamp and a guide plate.

[0010] The clamp includes a sleeve, end caps, bolts, and nuts. The sleeve is a cylindrical body with open ends. The open ends of the sleeve are sealed by end caps. The end caps have a spoke structure. The end caps include an outer ring, an inner ring, and a spoke structure connecting the inner and outer rings. The outer ring abuts against the end of the sleeve.

[0011] The guide plate is a replaceable plate with the same tooth shape as the gear to be polished. The thickness of the guide plate is marked as the length of the guide section. The gear to be polished is arranged in the inner cavity of the sleeve. The gear to be polished is arranged vertically in the axial direction. Guide plates are installed at both the upper and lower ends of the gear to be polished.

[0012] The bolt shank passes sequentially through the inner ring of the upper end cap, the upper toothed guide plate, the inner hole of the gear to be polished, the lower toothed guide plate, and the inner ring of the lower end cap before being screwed into the nut. The bolt and nut work together to lock the end caps, the gear to be polished, and the guide plate on both sides. The sleeve, end caps, gear to be polished, and toothed guide plate together form a sealed flow channel.

[0013] During operation, the sleeve is placed on the transition plate of the abrasive flow mill to bear the clamping force. The piston in the feed cylinder pushes the abrasive media under the action of the hydraulic system, and the abrasive media polishes the tooth surface of the gears through the sealed flow channel.

[0014] Furthermore, an annular groove is provided on the outer ring of the end cap facing the sleeve. An annular flange is provided on the end face of the sleeve. The annular flange and the annular groove fit together to achieve a seal.

[0015] Furthermore, it also includes gaskets. A gasket is provided between the bolt head and the upper end cap. A gasket is provided between the nut and the lower end cap.

[0016] Furthermore, the gear to be polished is a spur gear or a helical gear.

[0017] This invention also discloses an abrasive flow polishing method for uniformizing gear tooth surfaces, which uses the apparatus described in any one of the above claims to extend the inlet transition zone and construct a controllable flow channel. The method includes the following steps:

[0018] 1) Theoretical modeling preparation before simulation. Determine the parameters of the gear to be polished and set the abrasive flow processing path. Establish the abrasive flow medium path channel model in the simulation software. The number of teeth on the gear to be polished is n. The closed flow channel can be divided into n parts along the circumferential direction. Each part includes a fan-shaped flow channel, a guide flow channel, and an inter-tooth flow channel of the gear body.

[0019] 2) For key parameters that affect polishing uniformity, generate multiple parameter combinations within the empirical range.

[0020] 3) Dynamic process modeling and data generation. Abrasive flow dynamics simulation is performed based on each set of parameters, and the pressure-velocity product at each position on the tooth surface is recorded.

[0021] 4) Establish a mapping relationship between parameters and the uniformity of the pressure-velocity multiplicative distribution using Gaussian process regression, and quantify the uniformity using root mean square error. By analyzing the parameter-RMSE response surface, locate the optimal parameter set corresponding to the minimum RMSE, and form a process plan that can directly guide production.

[0022] 5) Configure the toothed drainage plate and sleeve according to the drainage section length value in the optimization results.

[0023] 6) Use a clamp to fix the gear to be polished on the abrasive flow machine tool to complete the clamping. The piston in the material cylinder pushes the abrasive medium under the action of the hydraulic system. The abrasive medium polishes the tooth surface of the gear through the inter-tooth flow channel.

[0024] Furthermore, the Latin hypercube sampling method is used to generate multiple sets of parameter combinations within its empirical range.

[0025] Furthermore, key parameters include inlet pressure, back pressure, and drainage section length.

[0026] The technical effects of this invention are undeniable: tooth-shaped guide vanes of the same shape as the gear are installed at both the upper and lower ends of the gear, respectively, introducing a guide section design to reduce the influence of the inlet effect and constructing a flow channel model for abrasive flow media. The main parameters affecting the experiment are sampled and grouped using the Latin hypercube sampling method, and simulation experiments are conducted in each group to obtain simulation data. Gaussian process regression is used for parameterized training to obtain the root mean square error of the material removal rate. The experimental parameter conditions corresponding to the minimum root mean square error are found, resulting in a set of optimal inlet pressure, back pressure, and guide section length abrasive flow processing parameters. Finally, these parameters are used to guide experiments, ensuring uniform material removal from the gear surface. This invention is applicable to both spur gears and helical gears, demonstrating strong versatility. Attached Figure Description

[0027] Figure 1 Flowchart of an abrasive flow polishing method for uniformizing gear tooth surfaces;

[0028] Figure 2 This is a model diagram of a helical gear;

[0029] Figure 3 This is a model diagram of a spur gear;

[0030] Figure 4 Schematic diagram of gear clamp design;

[0031] Figure 5 Exploded view of the gear clamp;

[0032] Figure 6 This is a flow path diagram of the abrasive medium in helical gears.

[0033] Figure 7 This is a flow path diagram of the abrasive medium in spur gears.

[0034] Figure 8 For the simulation of helical gears P i V i Data chart;

[0035] Figure 9 For the simulation of spur gears P i V i Data chart;

[0036] Figure 10 A graph showing the relationship between inlet pressure, back pressure, and RMSE value for helical gears;

[0037] Figure 11 A graph showing the relationship between helical gear inlet pressure, diversion section length, and RMSE value;

[0038] Figure 12 A graph showing the relationship between helical gear back pressure, guide section length, and RMSE value;

[0039] Figure 13 A graph showing the relationship between inlet pressure, back pressure, and RMSE value for spur gears;

[0040] Figure 14 A graph showing the relationship between spur gear inlet pressure, guide section length, and RMSE value;

[0041] Figure 15 A graph showing the relationship between spur gear back pressure, drainage section length, and RMSE value;

[0042] Figure 16 This is a schematic diagram of the abrasive flow polishing principle.

[0043] In the figure: clamp 1, sleeve 101, end cap 102, bolt 103, nut 104, washer 105, gear to be polished 2, toothed guide plate 3, fan-shaped space path flow channel 401, guide section flow channel 402, inter-tooth flow channel 403, abrasive flow machine tool 5, piston 6, material cylinder 7, abrasive media 8. Detailed Implementation

[0044] The present invention will be further described below with reference to embodiments, but it should not be construed that the scope of the present invention is limited to the following embodiments. Various substitutions and modifications made based on ordinary technical knowledge and common practices in the art without departing from the above-described technical concept of the present invention should be included within the scope of protection of the present invention.

[0045] Example 1:

[0046] See Figure 4 and Figure 5 This embodiment provides an abrasive flow polishing device for uniformizing gear tooth surfaces, including a clamp 1 and a guide plate 3.

[0047] The clamp 1 includes a sleeve 101, an end cap 102, a bolt 103, a nut 104, and a washer 105. The sleeve 101 is a cylindrical body with open ends. The open ends of the sleeve 101 are sealed by the end cap 102. The end cap 102 has a spoke structure. The end cap 102 includes an outer ring, an inner ring, and spokes connecting the inner and outer rings. The outer ring abuts against the end of the sleeve 101. An annular groove is provided on the upper side of the outer ring of the end cap 102 facing the sleeve 101. An annular flange is provided on the end face of the sleeve 101. The annular flange engages with the annular groove to achieve a seal.

[0048] The guide plate 3 is a replaceable plate with the same tooth shape as the gear 2 to be polished. The thickness of the guide plate 3 is marked as the length of the guide section. The gear 2 to be polished is arranged in the inner cavity of the sleeve 101. The gear 2 to be polished is arranged vertically in the axial direction. The guide plates 3 are installed at both the upper and lower ends of the gear 2 to be polished.

[0049] The shank of the bolt 103 passes sequentially through the inner ring of the upper end cap 102, the upper toothed guide plate 3, the inner hole of the gear 2 to be polished, the lower toothed guide plate 3, and the inner ring of the lower end cap 102 before being screwed into the nut 104. The bolt 103 and the nut 104 lock the double end caps 102, the gear 2 to be polished, and the guide plate 3 in a coordinated manner. A washer 105 is provided between the head of the bolt 103 and the upper end cap 102. A washer 105 is provided between the nut 104 and the lower end cap 102. The sleeve 101, end cap 102, gear 2 to be polished, and toothed guide plate 3 enclose a sealed flow channel 4.

[0050] When working, see Figure 16 The sleeve 101 is placed on the abrasive flow mill 5 to bear the clamping force. Two material cylinders 7 and a clamp 1 are fixedly installed on the abrasive flow mill 5. The clamp 1 is arranged between the two material cylinders 7. The upper and lower ends of the mold 1 are sealed to the material cylinders 7. A piston 6 is installed inside each material cylinder 7. The piston 6 is slidably connected to the cylinder body 7. A cavity is formed between the piston 6, the material cylinders 7, and the clamp 1, and the cavity is filled with abrasive media 8. Under the action of the hydraulic system, the piston 6 pushes the abrasive media 8 through the sealed flow channel 4 to polish the tooth surface of the gears.

[0051] Example 2:

[0052] This embodiment provides an abrasive flow polishing method for uniformizing gear tooth surfaces, employing the apparatus described in Embodiment 1 to extend the inlet transition zone and construct a controllable flow channel. The method includes the following steps:

[0053] 1) Theoretical modeling preparation before simulation. Determine the parameters of the gear to be polished and set the abrasive flow processing path. Establish the abrasive flow medium path channel model in the simulation software. The number of teeth on the gear 2 to be polished is n. The closed flow channel 4 can be divided into n parts along the circumferential direction. Each part includes a fan-shaped flow channel 401, a guide section flow channel 402, and an inter-tooth flow channel 403 of the gear body.

[0054] 2) For key parameters affecting polishing uniformity, multiple parameter combinations are generated within empirical ranges. The Latin hypercube sampling method is used to generate these combinations within their empirical ranges. Key parameters include inlet pressure, back pressure, and drainage section length.

[0055] 3) Dynamic process modeling and data generation. Abrasive flow dynamics simulation is performed based on each set of parameters, and the pressure-velocity product at each position on the tooth surface is recorded.

[0056] 4) Establish a mapping relationship between parameters and the uniformity of the pressure-velocity multiplicative distribution using Gaussian process regression, and quantify the uniformity using root mean square error. By analyzing the parameter-RMSE response surface, locate the optimal parameter set corresponding to the minimum RMSE, and form a process plan that can directly guide production.

[0057] 5) Configure toothed drainage plate 3 according to the drainage section length value in the optimization results.

[0058] 6) Fix the gear 2 to be polished on the abrasive flow machine tool using clamp 1 to complete the clamping. The piston in the material cylinder pushes the abrasive medium under the action of the hydraulic system. The abrasive medium polishes the tooth surface of the gear through the inter-tooth flow channel.

[0059] Example 3:

[0060] This embodiment provides an abrasive flow polishing method for homogenizing the tooth surface of helical gears. The method flow is described in [link to method details]. Figure 1 Specifically, it includes the following steps:

[0061] Step 1: Determine the parameters of the helical gear. The parameters of the helical gear are shown in Table 1, and the helical gear model is as follows. Figure 2 As shown.

[0062] Table 1 Helical Gear Parameters

[0063]

[0064]

[0065] The piston in the feed cylinder, driven by a hydraulic system, propels the abrasive media. The abrasive media reciprocates within a closed flow channel, polishing the helical gear teeth. To mitigate the adverse effects of the inlet effect, guide sections are designed above and below the inter-tooth flow channel of the helical gear. Tooth-shaped guide plates, identical in shape to the helical gear, are installed at both ends above and below the gear. The inter-tooth flow channels of these tooth-shaped guide plates serve as the guide section channels, and the length of the guide section is adjusted by changing the thickness of the tooth-shaped guide plates. The abrasive polishing media flows out of the feed cylinder, which is directly connected to the end cap. The spokes of the end cap directly contact the gear end face and the tooth-shaped guide plate end face, without affecting the flow rate of the abrasive polishing media into the inter-tooth flow channel. The volume of the spokes can be ignored within the end cap cavity, and the hollow part of the end cap cavity can be approximated as a cylinder. The helical gear has 23 teeth. The hollow cylindrical spatial path flow channel inside the end cover can be considered as being composed of 23 identical sector-shaped spatial path flow channels. The abrasive medium flow rate of each sector-shaped spatial path flow channel is equal to the abrasive medium flow rate flowing into its corresponding cylindrical spatial path flow channel. The abrasive medium flows uniformly from the 23 upper sector-shaped path channels into the 23 corresponding guide channel channels, then polishes the gear teeth through the inter-tooth channel of the helical gear, before flowing out of the 23 corresponding guide channel channels, and finally into the spatial path channels of the 23 lower sector-shaped sections. The central angle of each sector is [value missing]. Integrating the pressure on the sector surface over its area gives the pressure applied by the abrasive flow polishing equipment. For ease of calculation and analysis, this complex model is simplified into 23 simple and identical flow channel models based on the flow path of the abrasive medium. Only one of these flow channel models is selected for study and analysis, such as... Figure 6 As shown, each flow channel model consists of a fan-shaped spatial path flow channel 401 inside the end cap, a flow channel 402 between the upper and lower toothed flow channels, and a flow channel 403 between the teeth of a helical gear.

[0066] Step 2: Abrasive flow machining of helical gear tooth surfaces. Polishing accuracy is affected by inlet pressure, back pressure and guide section length. There is an empirical range of values ​​in daily processing. The main parameters affecting the experimental polishing accuracy are sampled and grouped using the Latin hypercube sampling method, as shown in Table 2.

[0067] Table 2. Experimental parameters for helical gears were sampled using Latin hypercube sampling.

[0068]

[0069]

[0070] Step 3: Based on the parameter grouping obtained by Latin hypercube sampling, guide the abrasive flow polishing simulation to obtain the simulation P of the helical gear tooth surface under different experimental parameters. i V i Data, such as Figure 8 As shown, the simulation P of the helical gear under the experimental parameters of an inlet pressure of 5002.80 N, a back pressure of -972.54 N, and a guide section length of 21.30 mm is presented. i V i The data graph, according to the Preston equation, has the general form: MRR = K·P·V

[0071] Where: MRR represents the material removal rate; k is an empirical constant that depends on the material of the abrasive flow; P represents the pressure exerted on the polished surface by the abrasive medium during the polishing process; and V represents the relative sliding velocity between the polished surface and the abrasive medium.

[0072] The workpiece has a constant material density, and the flow in the channel is steady. According to the Preston equation, the material removal rate in abrasive flow polishing is proportional to the product of the flow velocity and pressure of the abrasive flow polishing medium flowing over the workpiece surface. Since the abrasive flow polishing machine uses bidirectional extrusion abrasive flow polishing, this study investigates the material removal rate and simulated value PiVi of the helical gear surface, defined as PiVi = P1V1 + P2V2, where P represents the pressure of the polishing surface on the abrasive medium during polishing, V represents the relative sliding velocity between the polishing surface and the abrasive medium, and the subscripts "1" and "2" represent the two flow directions of the bidirectional extrusion abrasive flow, respectively. The simulated PiVi data for each set are recorded, and the material removal rate under different parameter conditions is compared.

[0073] Step 4: Using Gaussian process regression, parameterized training is performed to obtain the root mean square error (RMSE) of the helical gear tooth surface simulation data PiVi under different experimental parameters. RMSE is a commonly used measure of the difference between measured values. The smaller the RMSE of the simulation data PiVi, the more uniform the material removal and the more ideal the effect. The minimum RMSE for all experimental simulation groups is 0.9458. Gaussian process regression is used to find the corresponding experimental parameter conditions, such as... Figure 10 , Figure 11 and Figure 12 As shown, the relationship between inlet pressure, back pressure, guide section length, and RMSE value for abrasive flow polishing of helical gear tooth surfaces was obtained. The experimental parameters corresponding to an RMSE of 0.9458 were determined: inlet pressure of 5002.80 N, back pressure of -972.54 N, and guide section length of 21.30 mm. A set of optimal abrasive flow processing parameters was obtained to guide abrasive flow polishing for homogenizing helical gear tooth surfaces.

[0074] Step 5: Based on the optimization results, the length of the drainage section is 21.30mm, and the thickness of the toothed drainage plate is configured to be 21.30mm.

[0075] Step 6: Use clamp 1 to fix helical gear 2 onto the abrasive flow polishing equipment. A schematic diagram of the gear clamp design is shown below. Figure 4 As shown, the exploded view of the gear clamp is as follows: Figure 5 As shown, the fixture 1 is placed on the transition plate of the abrasive flow polishing equipment to bear the clamping force, preventing the helical gear from deforming during processing, and simultaneously positioning the helical gear to prevent displacement during processing. The fixture 1 consists of a sleeve 101, an end cap 102, a bolt 103, a nut 104, and a washer 105. The sleeve 101 has a cylindrical inner cavity, in which the helical gear 2 is axially and vertically arranged. Identical toothed guide plates 3 are installed at the upper and lower ends of the helical gear 2. The concave part of the end cap 102 mates with the convex part of the sleeve 101. The upper and lower end caps 102 communicate with the material cylinder, and a washer 105 is placed above the center of the upper end cap 102. 5. Bolt 103 passes through the inner cavity of the lower end cover 102, toothed guide plate 3, and helical gear 2. Nut 104 engages with bolt 103 through washer 105. The entire fixture 1, helical gear 2, and guide plate 3 are fixedly clamped by the end cover 102 on the other side. The helical gear and the toothed guide plates at the upper and lower ends are axially fixed together by the spokes of the fixture end cover. Sleeve 101, end cover 102, helical gear 2, and toothed guide plate 3 enclose a closed flow channel 4. The fixture has clamped the helical gear. The upper and lower hydraulic cylinders alternately squeeze the abrasive. The abrasive medium flows back and forth in the formed closed flow channel 4, thereby deburring and polishing the tooth surface of the helical gear.

[0076] Example 4:

[0077] This embodiment provides an abrasive flow polishing method for homogenizing the tooth surface of spur gears. The method flow is described in [link to method details]. Figure 1 Specifically, it includes the following steps:

[0078] Step 1: Determine the parameters of the spur gear. The parameters of the spur gear are shown in Table 3, and the spur gear model is as follows. Figure 3 As shown.

[0079] Table 3 Spur Gear Parameters

[0080]

[0081] The piston in the feed cylinder, driven by a hydraulic system, propels the abrasive media. The abrasive media reciprocates within a closed flow channel, polishing the spur gear teeth. To mitigate the adverse effects of the inlet effect, guide sections are designed above and below the inter-tooth flow channel of the spur gear. Tooth-shaped guide plates, identical in shape to the spur gear, are installed at both the upper and lower ends. The inter-tooth flow channels of these tooth-shaped guide plates serve as the guide section channels, and the length of the guide section is adjusted by changing the thickness of the tooth-shaped guide plates. The abrasive polishing media flows out of the feed cylinder, which is directly connected to the end cover. The spokes of the end cover directly contact the gear end face and the end face of the tooth-shaped guide plates, without affecting the flow rate of the abrasive polishing media into the inter-tooth flow channel. The volume of the spokes can be ignored within the end cover cavity, and the hollow part of the end cover cavity can be approximated as a cylinder. The spur gear has 23 teeth. The hollow cylindrical space path flow channel inside the end cover can be considered as being composed of 23 identical sector-shaped space path flow channels. The abrasive medium flow rate of each sector-shaped space path flow channel is equal to the abrasive medium flow rate flowing into its corresponding cylindrical space path flow channel. The abrasive medium flows uniformly from the 23 upper sector-shaped path channels into the 23 corresponding guide channel channels, then polishes the gear teeth through the inter-tooth channel of the spur gear, before flowing out of the 23 corresponding guide channel channels, and finally into the spatial path channels of the 23 lower sector-shaped sections. The central angle of each sector is [value missing]. Integrating the pressure on the sector surface over its area gives the pressure applied by the abrasive flow polishing equipment. For ease of calculation and analysis, this complex model is simplified into 23 simple and identical flow channel models based on the flow path of the abrasive medium. Only one of these flow channel models is selected for study and analysis, such as... Figure 7 As shown, each flow channel model consists of a fan-shaped spatial path flow channel 401 inside the end cap, a flow channel 402 between the upper and lower toothed flow channels, and a spur gear inter-tooth flow channel 403.

[0082] Step 2: Abrasive flow machining of spur gear tooth surfaces. The polishing accuracy is affected by inlet pressure, back pressure and guide section length. There is an empirical range of values ​​in daily processing. The main parameters affecting the experimental polishing accuracy are sampled and grouped using the Latin hypercube sampling method, as shown in Table 4.

[0083] Table 4. Experimental parameters for spur gears were sampled using Latin hypercube sampling.

[0084]

[0085]

[0086] Step 3: Based on the parameter set obtained from Latin hypercube sampling, guide the abrasive flow polishing simulation to obtain the simulation P of the spur gear tooth surface under different experimental parameters. i V i Data, such as Figure 9 The figure shows the simulated P of the spur gear under the experimental parameters of an inlet pressure of 5079.75 N, a back pressure of -893.06 N, and a guide section length of 19.82 mm. i V i The data graph, according to the Preston equation, has the general form: MRR = K·P·V

[0087] Where: MRR represents the material removal rate; k is an empirical constant that depends on the material of the abrasive flow; P represents the pressure exerted on the polished surface by the abrasive medium during the polishing process; and V represents the relative sliding velocity between the polished surface and the abrasive medium.

[0088] The workpiece has a constant material density and the flow in the channel is steady. According to the Preston equation, the material removal rate in abrasive flow polishing is proportional to the product of the flow velocity and pressure of the abrasive flow polishing medium flowing over the workpiece surface. Since the abrasive flow polishing machine uses bidirectional extrusion abrasive flow polishing, this study investigates the material removal rate and simulated numerical value P on the surface of the spur gear. i V i Defined as P i V i =P1V1 + P2V2, where P represents the pressure exerted on the polished surface by the abrasive medium during polishing, V represents the relative sliding velocity between the polished surface and the abrasive medium, and the subscripts "1" and "2" represent the two flow directions of the bidirectional extrusion abrasive flow, respectively. Record the simulation data P for each set. i V i The material removal rates under different parameter conditions were compared.

[0089] Step 4: Use Gaussian process regression to perform parametric training and obtain the simulated P of the spur gear tooth surface under different experimental parameters. i V i The root mean square error (RMSE) of the data is a commonly used measure of the difference between numerical values. Which simulation P-value... i V i The smaller the root mean square error (RMSE) of the data, the more uniform the material removal and the more ideal the effect. The minimum RMSE for all experimental simulation groups was 0.5637. Gaussian process regression was used to find the corresponding experimental parameters, such as... Figure 13 , Figure 14 and Figure 15 As shown, the relationship between inlet pressure, back pressure, guide section length, and RMSE value for abrasive flow polishing of spur gear tooth surfaces was obtained. The experimental parameters corresponding to an RMSE of 0.5637 were determined: inlet pressure of 5079.75 N, back pressure of -893.06 N, and guide section length of 19.82 mm. A set of optimal abrasive flow processing parameters was obtained to guide abrasive flow polishing for homogenizing spur gear tooth surfaces.

[0090] Step 5: Based on the drainage section length of 19.82mm in the optimization results, configure the thickness of the toothed drainage plate to be 19.82mm.

[0091] Step 6: Use clamp 1 to fix spur gear 2 onto the abrasive flow polishing equipment. A schematic diagram of the gear clamp design is shown below. Figure 4 As shown, the exploded view of the gear clamp is as follows: Figure 5 As shown, the fixture 1 is placed on the transition plate of the abrasive flow polishing equipment to bear the clamping force, preventing the spur gear from deforming during processing, and simultaneously positioning the spur gear to prevent displacement during processing. The fixture 1 consists of a sleeve 101, an end cap 102, a bolt 103, a nut 104, and a washer 105. The sleeve 101 has a cylindrical inner cavity, in which the spur gear 2 is axially and vertically arranged. Identical toothed guide plates 3 are installed at the upper and lower ends of the spur gear 2. The concave portion of the end cap 102 mates with the convex portion of the sleeve 101. The upper and lower end caps 102 communicate with the material cylinder, and a washer 105 is placed above the center of the upper end cap 102. 5. Bolt 103 passes through the inner cavity of the lower end cover 102, toothed guide plate 3, and spur gear 2. Nut 104 engages with bolt 103 through washer 105. The entire fixture 1, spur gear 2, and guide plate 3 are fixedly clamped by the end cover 102 on the other side. The spur gear and the toothed guide plates at both ends are axially fixed together by the spokes of the fixture end cover. Sleeve 101, end cover 102, spur gear 2, and toothed guide plate 3 enclose a closed flow channel 4. The fixture has clamped the spur gear. The upper and lower hydraulic cylinders alternately squeeze the abrasive. The abrasive medium flows back and forth in the formed closed flow channel 4, thereby deburring and polishing the tooth surface of the spur gear.

Claims

1. A method for abrasive flow polishing to homogenize gear tooth surfaces, characterized in that: An abrasive flow polishing device is used to extend the inlet transition zone and construct a controllable flow channel; the abrasive flow polishing device includes a fixture (1) and a flow guide plate (3). The clamp (1) includes a sleeve (101), an end cap (102), a bolt (103), and a nut (104); the sleeve (101) is a cylindrical body with open ends; the open ends of the sleeve (101) are sealed by the end cap (102); the end cap (102) is a spoke structure; the end cap (102) includes an outer ring, an inner ring, and a spoke structure connecting the inner ring and the outer ring; the outer ring abuts against the end of the sleeve (101); The guide plate (3) is a replaceable plate with the same tooth shape as the gear (2) to be polished; the thickness of the guide plate (3) is marked as the length of the guide section; the gear (2) to be polished is arranged in the inner cavity of the sleeve (101); the gear (2) to be polished is arranged vertically in the axial direction; the guide plates (3) are installed at the upper and lower ends of the gear (2) to be polished. The shank of the bolt (103) passes sequentially through the inner ring of the upper end cap (102), the upper toothed guide plate (3), the inner hole of the gear (2) to be polished, the lower toothed guide plate (3), and the inner ring of the lower end cap (102) before being screwed into the nut (104); the bolt (103) and the nut (104) lock the double end caps (102), the gear (2) to be polished, and the guide plate (3) in a coordinated manner; the sleeve (101), the end cap (102), the gear (2) to be polished, and the guide plate (3) together form a closed flow channel (4); During operation, the sleeve (101) is placed on the transition plate of the abrasive flow machine tool to bear the clamping force; the piston in the material cylinder pushes the abrasive medium under the action of the hydraulic system, and the abrasive medium polishes the tooth surface of the gear through the closed flow channel (4); The method includes the following steps: S1) Theoretical modeling preparation before simulation; determine the parameters of the gear to be polished and set the abrasive flow processing path; establish the abrasive flow medium path flow channel model in the simulation software; wherein, the number of teeth of the gear to be polished (2) is n; the closed flow channel (4) is divided into n parts along the circumferential direction; each part includes a fan-shaped flow channel (401), a guide section flow channel (402) and an inter-tooth flow channel (403) of the gear body. S2) For key parameters affecting polishing uniformity, generate multiple sets of parameter combinations within the empirical value range; S3) Dynamic process modeling and data generation; perform abrasive flow dynamics simulation based on each set of parameters, and record the pressure-velocity product at each position on the tooth surface; S4) Use Gaussian process regression to establish the mapping relationship between parameters and pressure-velocity multiplicative distribution uniformity, and use root mean square error to quantify uniformity; by analyzing the parameter-RMSE response surface, locate the optimal parameter set corresponding to the minimum RMSE, and form a process plan that can directly guide production. S5) Based on the length value of the drainage section in the optimization results, configure the toothed drainage plate (3) and the sleeve (101). S6) Use the clamp (1) to fix the gear (2) to be polished on the abrasive flow machine tool to complete the clamping. The piston in the material cylinder pushes the abrasive medium under the action of the hydraulic system. The abrasive medium polishes the tooth surface of the gear through the inter-tooth flow channel.

2. The abrasive flow polishing method for uniformizing gear tooth surfaces according to claim 1, characterized in that: An annular groove is provided on the outer ring of the end cap (102) facing the sleeve (101); an annular flange is provided on the end face of the sleeve (101); the annular flange and the annular groove are fitted together to achieve a seal.

3. The abrasive flow polishing method for uniformizing gear tooth surfaces according to claim 1, characterized in that: It also includes a washer (105); a washer (105) is provided between the head of the bolt (103) and the upper end cap (102); a washer (105) is provided between the nut (104) and the lower end cap (102).

4. The abrasive flow polishing method for uniformizing gear tooth surfaces according to claim 1, characterized in that: The gear to be polished (2) is a spur gear or a helical gear.

5. The abrasive flow polishing method for uniformizing gear tooth surfaces according to claim 1, characterized in that: The Latin hypercube sampling method is used to generate multiple sets of parameter combinations within the empirical range.

6. The abrasive flow polishing method for uniformizing gear tooth surfaces according to claim 5, characterized in that: Key parameters include inlet pressure, back pressure, and drainage section length.

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