High-precision injection molding gear water gap cutting method and device

Abstract

The invention discloses a high-precision injection-molded gear water gap cutting method and device, and the method comprises the steps: transferring an injection-molded gear blank to a scanning station through a manipulator, carrying out the three-dimensional scanning of a water gap region through a 3D scanner, generating three-dimensional model data, extracting the height, diameter and position parameters of a water gap, and carrying out the machining of the water gap. The control module plans the cutting depth and the chamfering angle and generates a self-adaptive cutting instruction; then, a force feedback executing mechanism drives a tool to execute cutting, meanwhile, a multi-dimensional force sensor monitors cutting resistance in real time, and when the resistance exceeds a threshold value, the feeding speed is dynamically adjusted, and machining force curve data are recorded; performing secondary scanning on the cutting surface at the same station, and comparing the actually measured point cloud with the design model to generate a quality report containing flatness error and residual height; water gap feature modeling is achieved through three-dimensional scanning, cutting parameters are dynamically optimized in combination with real-time force feedback, the problem of overcutting or residue is solved, the product yield is increased, the production efficiency is remarkably improved, and the production cost is reduced.

Description

Technical Field

[0001] The present invention relates to the field of injection molding technology, and in particular to a high-precision injection molding gear water nozzle cutting method and device. Background Art

[0002] Plastic gears, due to their advantages such as lightweight, corrosion resistance, and low noise, have been widely used in automotive electronics, medical devices, precision instruments, and other fields. With the increasing precision requirements of industrial equipment, high-precision injection-molded gears must ensure tooth profile tolerances and end face runout ≤0.03mm. These gears are generally molded using a center-point injection process, which allows the molten plastic to spread evenly from the center of the gear, significantly reducing shrinkage anisotropy caused by differential cooling rates. However, any remaining sprue in the center of the gear after injection molding must be precisely removed to prevent it from affecting gear assembly accuracy and transmission performance.

[0003] The current mainstream gate cutting technology uses a fixed programmed processing device: the gate is cut by pre-setting the tool travel and feed speed (such as the single gate method). This method has significant drawbacks: Fluctuations in nozzle dimensions lead to uncontrolled cutting accuracy. Due to injection molding process fluctuations (temperature and pressure variations), the actual nozzle height and diameter deviate. Fixed cutting parameters cannot dynamically adapt to the actual nozzle geometry, resulting in overcutting (damaging the gear substrate) or residue, leading to high product defect rates. Manual spot checks can partially alleviate this problem, but they severely restrict production cycle time (increasing processing time per piece) and fail to fundamentally resolve process consistency issues.

[0004] In view of this, it is necessary to improve the existing nozzle cutting technology to solve the technical problem of uncontrollable cutting accuracy of injection molded gears due to nozzle size fluctuations. Summary of the Invention

[0005] The purpose of the present invention is to provide a high-precision injection molding gear cutting nozzle method and device to solve the above technical problems.

[0006] To achieve this object, the present invention adopts the following technical solutions: A high-precision injection molding gear watertightening method is performed using a cutting device linked to an injection molding machine. The cutting device includes a visual inspection system, a control module, and a force feedback actuator. The visual inspection system includes a 3D scanner, and the tool spindle of the force feedback actuator is integrated with a multi-dimensional force sensor. The watertightening method includes the following steps: The injection-molded gear blank is transferred to the scanning station by a robot, and the visual inspection system performs a three-dimensional scan on the gate area to generate three-dimensional model data of the gate; Extracting nozzle height, diameter, and position parameters based on the three-dimensional model data, planning cutting depth and chamfer angle through a control module, and generating adaptive cutting instructions; The force feedback actuator drives the tool to cut the water nozzle according to the adaptive cutting instruction, and monitors the cutting resistance in real time through the multi-dimensional force sensor. When the resistance exceeds a preset threshold, the feed speed is dynamically adjusted and the processing force curve data is recorded; The cutting surface is scanned a second time at the same workstation, and the measured point cloud data is compared with the design model to generate a quality report including flatness error and residual height.

[0007] Optionally, the nozzle height, diameter, and position parameters are extracted based on the three-dimensional model data, and the cutting depth and chamfer angle are planned by the control module to generate an adaptive cutting instruction, which specifically includes the following steps: Performing point cloud filtering on the three-dimensional model data to remove environmental noise points and retain valid point cloud data of the water inlet area; Fitting the center axis of the nozzle based on the valid point cloud data, and establishing a cylindrical coordinate system with the center axis of the nozzle as a reference; The nozzle cross section is cut layer by layer in the cylindrical coordinate system, and the equivalent diameter of each layer of cross section and the height relative to the gear end face are calculated.

[0008] Optionally, the step of cutting the nozzle cross section in layers in a cylindrical coordinate system and calculating the equivalent diameter of each cross section and the height relative to the gear end face may further include: The control module extracts the maximum diameter Dmax of the nozzle top, the minimum diameter Dmin of the root and the total height H, combined with the position offset ΔP between the nozzle center axis and the gear axis; Calculate the actual cutting depth according to the formula: cutting depth Hcut = H × k1 - δ, where k1 is the safety margin factor, 0.90≤k1≤0.98, and δ is the tool wear compensation value; Based on Dmax, Dmin and ΔP, the spiral progressive tool path instruction and the generation rule of the chamfer angle θ are generated and compiled into the adaptive cutting instruction.

[0009] Optionally, the generation rule of the chamfer angle θ is: When the maximum diameter Dmax of the nozzle top is less than 3mm, set the chamfer angle θ to 45°; When the maximum diameter Dmax of the nozzle top is greater than or equal to 3 mm, the chamfer angle θ is set to 30°.

[0010] Optionally, the force feedback actuator drives the tool to cut the water nozzle according to the adaptive cutting instruction, and monitors the cutting resistance in real time through a multi-dimensional force sensor. When the resistance exceeds a preset threshold, the feed speed is dynamically adjusted, and processing force curve data is recorded, which specifically includes the following steps: Analyze the spiral progressive tool path, cutting depth Hcut and chamfer angle θ in the adaptive cutting instruction, and initialize the tool feed speed v0; The tool is driven along a spiral progressive tool path to cut into the water gate. At the same time, the cutting resistance F is collected in real time through a multi-dimensional force sensor and decomposed into axial resistance Fz and radial resistance Fr. When the axial resistance Fz exceeds the preset safety threshold range [0.8Fn, 1.2Fn], the feed speed v is dynamically adjusted according to the function v = v0 × (Fn / Fz)k2, where Fn is the standard cutting force of the material, k2 is the damping coefficient, 0.5≤k2≤1.0; During the chamfering stage, the ultrasonic vibration tool is switched to a vibration cutting frequency of 20-40 kHz, and the fluctuation amplitude of the radial resistance Fr is monitored. If the fluctuation value ΔFr>15%Fn, a tool wear warning is triggered; The time-resistance curve data is recorded synchronously to generate machining force curve data including axial resistance Fz, radial resistance Fr and adjusted feed speed v.

[0011] Optionally, performing a second scan on the cutting surface at the same workstation and comparing the measured point cloud data with the design model specifically includes the following steps: At the same workstation where cutting is completed, the visual inspection system is controlled to perform a second 3D scan of the water cut surface to obtain measured point cloud data; Perform coordinate system alignment on the measured point cloud data and establish a detection coordinate system consistent with the design model based on the gear axis; In the detection coordinate system, the measured point cloud data is spatially aligned with the design model, and the normal distance from the point cloud to the model surface is calculated.

[0012] Optionally, generating a quality report including flatness error and residual height specifically includes the following steps: Extract the point cloud within the first diameter range of the central area of ​​the cutting surface and calculate the flatness error ε = |zi - zavg|, where zi is the point cloud height value and zavg is the average height; Detect the residual nozzle height hr at the edge of the cutting surface. If there is a continuous area where hr> the allowed height, it will be marked as a residual defect; Integrate flatness error εf, residual height distribution map and residual defect markers to generate structured quality reports.

[0013] Optionally, generating a quality report including flatness error and residual height may further include: The process database is updated according to the quality report and the processing force curve data, by optimizing the cutting parameters and outputting the process parameter optimization instructions to the subsequent processing batches.

[0014] The present invention further provides an injection molding gear water nozzle cutting device, which adopts the high-precision injection molding gear water nozzle cutting method as described above, and the injection molding gear water nozzle cutting device includes a frame, and the frame is sequentially integrated with a scanning station, a transplanting mechanism, a cutting mechanism, a chamfering mechanism, a quality inspection mechanism and a control cabinet, and the control module is integrated into the control cabinet; The scanning station is arranged in the middle of the frame, and is correspondingly integrated with a visual inspection system; The transfer mechanism includes a mechanical arm for connecting the scanning station, the cutting mechanism and the chamfering mechanism, and the mechanical arm is provided with a product fixing cylinder, a Z-direction cylinder and an X-direction cylinder.

[0015] Optionally, the cutting mechanism includes a servo-driven Z-axis slide and a cutting spindle, and a tool is mounted on the lower end of the cutting spindle; The chamfering mechanism includes a chamfering spindle and a chamfering knife arranged at the lower end of the chamfering spindle. The chamfering spindle is integrated with an ultrasonic vibration unit. An air shower assembly for cleaning is provided on one side of the chamfering mechanism.

[0016] Compared with the prior art, the present invention has the following beneficial effects: first, the robot transfers the injection-molded gear blank to the scanning station, and the sprue area is scanned three-dimensionally by a 3D scanner to generate three-dimensional model data; the sprue height, diameter and position parameters are extracted based on the three-dimensional model data, and the control module plans the cutting depth and chamfer angle and generates adaptive cutting instructions; then the force feedback actuator drives the tool to perform cutting, and at the same time the multi-dimensional force sensor monitors the cutting resistance in real time, and dynamically adjusts the feed speed and records the processing force curve data when the resistance exceeds the threshold; the cutting surface is scanned a second time at the same station, and a quality report including flatness error and residual height is generated by comparing the measured point cloud with the design model, forming a complete process closed loop from detection to feedback; the method realizes sprue feature modeling through three-dimensional scanning, and dynamically optimizes cutting parameters in combination with real-time force feedback, which solves the overcutting or residual problem caused by sprue size fluctuations in traditional fixed program processing; the secondary scanning quality inspection link is directly linked to the design model to ensure the flatness error of the cutting surface and the absence of residual sprue, thereby improving product yield, significantly improving production efficiency and reducing overall cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0018] The structures, proportions, sizes, etc. depicted in the drawings of this specification are only used to match the contents disclosed in the specification so as to facilitate understanding and reading by persons familiar with this technology. They are not intended to limit the conditions under which the present invention can be implemented and therefore have no substantive technical significance. Any structural modifications, changes in proportional relationships, or adjustments in size should still fall within the scope of the technical contents disclosed in the present invention without affecting the effects and objectives that can be achieved by the present invention.

[0019] Figure 1 This is a schematic diagram of an actual product produced by the high-precision injection molding gear cutting method of the first embodiment; Figure 2 This is a method for cutting the water outlet of a high-precision injection molded gear according to the embodiment of the present invention. Figure 1 Schematic diagram of the cross-section structure at AA in the middle; Figure 3 Schematic diagram of the overall structure of the injection molding gear water nozzle device of the second embodiment; Figure 4 This is a schematic diagram of the main structure of the injection molding gear water cutting device of the second embodiment; Figure 5 Schematic diagram of the structure of the transplanting mechanism of the injection molding gear water nozzle device of the second embodiment.

[0020] Illustration: frame 100, scanning station 200, transfer mechanism 300, cutting mechanism 400, chamfering mechanism 500, quality inspection mechanism 600, control cabinet 700, robotic arm 301, fixed cylinder 302, Z-direction cylinder 303, X-direction cylinder 304, Z-axis slide 401, cutting spindle 402, tool 403, chamfering spindle 501, chamfering knife 502, air shower assembly 503. DETAILED DESCRIPTION

[0021] In order to make the purpose, features, and advantages of the present invention more obvious and easy to understand, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described below are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0022] In the description of the present invention, it should be understood that the terms "upper," "lower," "top," "bottom," "inner," "outer," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate the description of the present invention and simplify the description. They are not intended to indicate or imply that the devices or elements referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on the present invention. It should be noted that when a component is considered to be "connected" to another component, it may be directly connected to the other component or there may be a centrally located component.

[0023] The technical solution of the present invention will be further described below with reference to the accompanying drawings and through specific implementation methods.

[0024] Example 1: An embodiment of the present invention provides a high-precision injection molding gear water gate cutting method, which is performed using a cutting device linked to an injection molding machine. The cutting device includes a visual inspection system, a control module, and a force feedback actuator. The visual inspection system includes a 3D scanner, and the tool spindle of the force feedback actuator is integrated with a multi-dimensional force sensor. The water gate cutting method includes the following steps: S1, the injection molded gear blank is transferred to the scanning station by the robot, and the visual inspection system performs a three-dimensional scan of the gate area to generate the three-dimensional model data of the gate. Figure 1 and Figure 2 As shown, this is the actual three-dimensional model in this scheme.

[0025] S2 extracts nozzle height, diameter and position parameters based on 3D model data, plans cutting depth and chamfer angle through the control module, and generates adaptive cutting instructions; extracts nozzle height, diameter and position offset based on point cloud data, and dynamically plans cutting depth and chamfer angle through the algorithm.

[0026] In S3, the force feedback actuator drives the tool to cut the water nozzle according to the adaptive cutting instruction, and at the same time monitors the cutting resistance in real time through the multi-dimensional force sensor. When the resistance exceeds the preset threshold, the feed speed is dynamically adjusted and the processing force curve data is recorded.

[0027] S4 scans the cutting surface a second time at the same station, comparing the measured point cloud data with the design model to generate a quality report including flatness error and residual height. This avoids positioning errors caused by transplantation and achieves integrated processing and quality inspection.

[0028] S5, updates the process database based on the quality report and machining force curve data, optimizes the cutting parameters and outputs process parameter optimization instructions to subsequent machining batches.

[0029] The working principle of the present invention is as follows: first, the robot moves the injection-molded gear blank to the scanning station, and uses a 3D scanner to perform a three-dimensional scan of the nozzle area to generate three-dimensional model data; based on the three-dimensional model data, the nozzle height, diameter and position parameters are extracted, and the control module plans the cutting depth and chamfer angle and generates an adaptive cutting instruction; then the force feedback actuator drives the tool to perform cutting, and at the same time the multi-dimensional force sensor monitors the cutting resistance in real time. When the resistance exceeds the threshold, the feed speed is dynamically adjusted and the processing force curve data is recorded; the cutting surface is scanned a second time at the same station, and a quality report including flatness error and residual height is generated by comparing the measured point cloud with the design model, forming a complete process closed loop from detection to feedback; this method realizes nozzle feature modeling through three-dimensional scanning, and dynamically optimizes cutting parameters in combination with real-time force feedback, which solves the overcutting or residual problem caused by nozzle size fluctuations in traditional fixed program processing; the secondary scanning quality inspection link is directly linked to the design model to ensure the cutting surface flatness error and the absence of residual nozzle, thereby improving product yield, significantly improving production efficiency and reducing overall cost.

[0030] In this embodiment, it is specifically explained that step S2 specifically includes the following steps: S21, perform point cloud filtering on the 3D model data to remove environmental noise points and retain the valid point cloud data of the nozzle area; remove environmental noise (such as injection flash, dust reflection) through the outlier removal algorithm, and retain the valid point cloud of the nozzle body.

[0031] S22, fit the center axis of the nozzle based on the effective point cloud data, and establish a cylindrical coordinate system with the center axis of the nozzle as the reference; fit the center axis of the nozzle based on the least squares method, and establish a cylindrical coordinate system with the axis as the Z axis to eliminate the measurement reference error caused by the nozzle deflection and provide a unified reference for layered calculation.

[0032] S23 captures nozzle cross-sections layer by layer in a cylindrical coordinate system, calculating the equivalent diameter and height relative to the gear end face for each layer. Cross-sections are taken at fixed intervals (typically 0.1 mm) along the axis, and the equivalent diameter (area-equivalent circular diameter) of each layer is calculated. This captures the varying characteristics of nozzle taper, supporting precise cutting volume planning.

[0033] In step S24, the control module extracts the maximum diameter Dmax of the nozzle top, the minimum diameter Dmin of the root, and the total height H, and combines this with the positional offset ΔP between the nozzle center axis and the gear axis. From the layered data, the maximum diameter Dmax (which influences chamfer design), the minimum diameter Dmin of the root (which correlates with cutting resistance), the total height H (which determines cutting depth), and the axis offset ΔP (which reflects positioning error) are extracted. This quantifies the core parameters of injection molding fluctuations and provides input for adaptive control.

[0034] S25, calculate the actual cutting depth according to the formula: cutting depth Hcut=H×k1-δ, where k1 is the safety margin coefficient, 0.90≤k1≤0.98, and δ is the tool wear compensation value.

[0035] The actual cutting depth is calculated according to the formula Hcut=H×k1-δ, where: k1 (safety margin factor): retain 5%-10% margin to prevent overcutting; δ (Tool Wear Compensation): Dynamically corrects based on historical wear data (e.g., 0.05mm compensation for every 100 pieces processed); balances processing safety and efficiency to avoid residue or substrate damage caused by fixed depth.

[0036] S26, based on Dmax, Dmin and ΔP, a spiral progressive tool path instruction and a generation rule of the chamfer angle θ are generated and compiled into an adaptive cutting instruction.

[0037] Combine Dmax, Dmin and ΔP to generate a spiral progressive tool path: Small diameter nozzles (Dmin<2mm) use high speed and low feed; Large offset (ΔP>0.1mm) increases radial compensation path; The chamfer angle θ is set based on Dmax (see the following rules) to achieve coordinated optimization of the cutting path and process parameters.

[0038] In this embodiment, the generation rule of the chamfer angle θ is further described as follows: When the maximum diameter Dmax of the nozzle top is less than 3mm, the chamfer angle θ is set to 45°; a large chamfer is used for small nozzles to disperse edge stress and avoid center fracture of the gear.

[0039] When the maximum diameter Dmax of the nozzle top is greater than or equal to 3mm, set the chamfer angle θ to 30°. Large nozzles limit the chamfer angle to prevent excessive cutting that weakens the shaft hole strength.

[0040] Through diameter-related chamfering rules, a balance is achieved between deburring requirements and structural integrity, solving the stress concentration or insufficient strength problems caused by traditional fixed angles.

[0041] In this embodiment, it is specifically explained that step S3 specifically includes the following steps: S31, parsing the spiral progressive tool path, cutting depth Hcut and chamfer angle θ in the adaptive cutting instruction, and initializing the tool feed speed v0; The generated adaptive cutting instructions are parsed and loaded with the spiral progressive tool path, cutting depth Hcut, and chamfer angle θ. The feed rate v0 is initialized based on the default value in the material library (e.g., 150 mm / min for POM plastic), ensuring that the cutting action is strictly synchronized with the planned parameters.

[0042] S32, driving the tool along the spiral progressive tool path to cut into the water gate, while the cutting resistance F is collected in real time through the multi-dimensional force sensor and decomposed into axial resistance Fz and radial resistance Fr; As the tool enters the water gate along a spiral path, a multi-dimensional force sensor collects the total cutting resistance F in real time and decouples it into axial resistance Fz (reflecting the cutting load) and radial resistance Fr (reflecting tool runout). This enables multi-dimensional monitoring of the machining state and provides a basis for dynamic adjustment.

[0043] S33, when the axial resistance Fz exceeds the preset safety threshold range [0.8Fn, 1.2Fn], the feed speed v is dynamically adjusted according to the function v=v0×(Fn / Fz)k2, where Fn is the standard cutting force of the material, k2 is the damping coefficient, 0.5≤k2≤1.0; to solve the cutting risk caused by abnormal material hardness.

[0044] When Fz exceeds the safety threshold [0.8Fn, 1.2Fn] (Fn is the standard cutting force of the material), the feed speed is adjusted according to the function v=v0×(Fn / Fz)k2: Fz is too high (>1.2Fn): reduce speed to prevent chipping (the reduction is greatest when k2=1.0); Fz is too low (<0.8Fn): speed up and improve efficiency (the response is smooth when k2=0.5).

[0045] S34, during the chamfering stage, switches to the ultrasonic vibration tool, vibrates and cuts at a frequency of 20-40 kHz, and monitors the fluctuation amplitude of the radial resistance Fr. If the fluctuation value ΔFr>15%Fn, the tool wear warning is triggered.

[0046] S35 , synchronously recording the time-resistance curve data, and generating machining force curve data including the axial resistance Fz, the radial resistance Fr, and the adjusted feed speed v.

[0047] In this embodiment, it is specifically explained that step S4 specifically includes the following steps: S41, at the same workstation where cutting is completed, control the visual inspection system to perform a second three-dimensional scan of the water cut surface to obtain measured point cloud data; A secondary scan is triggered directly at the cutting station to avoid positioning deviations caused by transplantation. The 3D scanner obtains the measured point cloud of the cutting surface, ensuring that the inspection benchmark is strictly consistent with the processing benchmark, eliminating repeated positioning errors.

[0048] S42, performing coordinate system alignment processing on the measured point cloud data, and establishing a detection coordinate system consistent with the design model based on the gear axis; A detection coordinate system is established with the gear axis as the origin, and the measured point cloud is aligned with the design model coordinate system through feature matching to solve the detection distortion problem caused by gear clamping deflection.

[0049] S43: In the inspection coordinate system, the measured point cloud data is spatially registered with the design model, and the normal distance from the point cloud to the model surface is calculated. The measured point cloud and the design model surface are ICP-registered, and the normal distance from each point to the model surface is calculated to quantify the cutting surface topography deviation.

[0050] S44, extracting the point cloud within the first diameter range of the central area of ​​the cutting surface, and calculating the flatness error ε = |zi - zavg|, where zi is the point cloud height value and zavg is the average height.

[0051] S45, detect the residual nozzle height hr at the edge of the cutting surface. If there is a continuous area where hr is greater than the allowed height, it is marked as a residual defect; detect the residual nozzle height hr at the edge of the cutting surface. If there is a continuous area where hr is greater than 0.1mm (assembly gap tolerance limit), it is marked as a residual defect.

[0052] S46 integrates the flatness error εf, the residual height distribution map, and the residual defect markers to generate a structured quality report. This integrates the flatness error εflat, the residual height distribution map (color block diagram), and the defect markers to generate a readable quality report.

[0053] Example 2: Combine Figures 3 to 5 As shown, the present invention also provides an injection molding gear water cutting device, which adopts the high-precision injection molding gear water cutting method as in Example 1. The injection molding gear water cutting device includes a frame 100, on which a scanning station 200, a transplanting mechanism 300, a cutting mechanism 400, a chamfering mechanism 500, a quality inspection mechanism 600 and a control cabinet 700 are integrated in sequence, and the control module is integrated in the control cabinet 700; the scanning station 200 is arranged in the middle of the frame 100, and it is correspondingly integrated with a visual inspection system.

[0054] The transfer mechanism 300 includes a robotic arm 301 for connecting the scanning station 200, the cutting mechanism 400 and the chamfering mechanism 500. The robotic arm 301 is provided with a product fixing cylinder 302, a Z-direction cylinder 303 and an X-direction cylinder 304.

[0055] During operation, the gear blank is transferred to the scanning station 200 by the robotic arm 301, and a three-dimensional model of the sprue is generated by the 3D vision system; the control cabinet 700 plans the cutting instructions based on the model data, drives the transfer mechanism 300 to grab the workpiece through the product fixing cylinder 302, and accurately positions it to the cutting mechanism 400 (flat-bottom milling cutter performs adaptive cutting) and the chamfering mechanism 500 (ultrasonic vibration tool chamfering) by the Z / X cylinder; finally, the same station triggers the quality inspection mechanism 600 to scan again, and generates a quality report to feedback to the control cabinet 700.

[0056] In this embodiment, the cutting mechanism 400 includes a servo-driven Z-axis slide 401 and a cutting spindle 402, and a tool 403 is installed at the lower end of the cutting spindle 402; the chamfering mechanism 500 includes a chamfering spindle 501, and a chamfering knife 502 arranged at the lower end of the chamfering spindle 501, the chamfering spindle 501 is integrated with an ultrasonic vibration unit, and an air shower assembly 503 for cleaning is provided on one side of the chamfering mechanism 500.

[0057] As described above, the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that the technical solutions described in the above embodiments can still be modified, or some of the technical features thereof can be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A high-precision injection molding gear cutting method, which is performed by a cutting device linked to an injection molding machine, characterized in that: The cutting device includes a visual inspection system, a control module, and a force feedback actuator; wherein the visual inspection system includes a 3D scanner, and the tool spindle of the force feedback actuator is integrated with a multi-dimensional force sensor; the water cutting method includes the following steps: The injection-molded gear blank is transferred to the scanning station by a robot, and the visual inspection system performs a three-dimensional scan on the gate area to generate three-dimensional model data of the gate; Extracting nozzle height, diameter, and position parameters based on the three-dimensional model data, planning cutting depth and chamfer angle through a control module, and generating adaptive cutting instructions; The force feedback actuator drives the tool to cut the water nozzle according to the adaptive cutting instruction, and monitors the cutting resistance in real time through the multi-dimensional force sensor. When the resistance exceeds a preset threshold, the feed speed is dynamically adjusted and the processing force curve data is recorded; The cutting surface is scanned a second time at the same workstation, and the measured point cloud data is compared with the design model to generate a quality report including flatness error and residual height.

2. The high-precision injection molding gear water nozzle cutting method according to claim 1, characterized in that: The nozzle height, diameter and position parameters are extracted based on the three-dimensional model data, and the cutting depth and chamfer angle are planned by the control module to generate an adaptive cutting instruction, which specifically includes the following steps: Performing point cloud filtering on the three-dimensional model data to remove environmental noise points and retain valid point cloud data of the water inlet area; Fitting the center axis of the nozzle based on the valid point cloud data, and establishing a cylindrical coordinate system with the center axis of the nozzle as a reference; The nozzle cross section is cut layer by layer in the cylindrical coordinate system, and the equivalent diameter of each layer of cross section and the height relative to the gear end face are calculated.

3. The high-precision injection molding gear water nozzle cutting method according to claim 2, characterized in that: The above-mentioned method includes: cutting the nozzle cross section layer by layer in the cylindrical coordinate system, calculating the equivalent diameter of each cross section and the height value relative to the gear end face, and then further including: The control module extracts the maximum diameter Dmax of the nozzle top, the minimum diameter Dmin of the root and the total height H, combined with the position offset ΔP between the nozzle center axis and the gear axis; Calculate the actual cutting depth according to the formula: cutting depth Hcut = H × k1 - δ, where k1 is the safety margin factor, 0.90≤k1≤0.98, and δ is the tool wear compensation value; Based on Dmax, Dmin and ΔP, the spiral progressive tool path instruction and the generation rule of the chamfer angle θ are generated and compiled into the adaptive cutting instruction.

4. The high-precision injection molding gear cutting method according to claim 3, characterized in that: The generation rule of the chamfer angle θ is: When the maximum diameter Dmax of the nozzle top is less than 3mm, set the chamfer angle θ to 45°; When the maximum diameter Dmax of the nozzle top is greater than or equal to 3 mm, the chamfer angle θ is set to 30°.

5. The high-precision injection molding gear cutting method according to claim 1, characterized in that: The force feedback actuator drives the tool to cut the water nozzle according to the adaptive cutting instruction, and monitors the cutting resistance in real time through a multi-dimensional force sensor. When the resistance exceeds a preset threshold, the feed speed is dynamically adjusted, and the processing force curve data is recorded. Specifically, the following steps are included: Analyze the spiral progressive tool path, cutting depth Hcut and chamfer angle θ in the adaptive cutting instruction, and initialize the tool feed speed v0; The tool is driven along a spiral progressive tool path to cut into the water gate. At the same time, the cutting resistance F is collected in real time through a multi-dimensional force sensor and decomposed into axial resistance Fz and radial resistance Fr. When the axial resistance Fz exceeds the preset safety threshold range [0.8Fn, 1.2Fn], the feed speed v is dynamically adjusted according to the function v = v0 × (Fn / Fz)k2, where Fn is the standard cutting force of the material, k2 is the damping coefficient, 0.5≤k2≤1.0; During the chamfering stage, the ultrasonic vibration tool is switched to a vibration cutting frequency of 20-40 kHz, and the fluctuation amplitude of the radial resistance Fr is monitored. If the fluctuation value ΔFr is greater than 15%Fn, a tool wear warning is triggered; The time-resistance curve data is recorded synchronously to generate machining force curve data including axial resistance Fz, radial resistance Fr and adjusted feed speed v.

6. The high-precision injection molding gear cutting method according to claim 1, characterized in that: The second scanning of the cutting surface at the same station and comparison of the measured point cloud data with the design model specifically include the following steps: At the same workstation where cutting is completed, the visual inspection system is controlled to perform a second 3D scan of the water cut surface to obtain measured point cloud data; Perform coordinate system alignment on the measured point cloud data and establish a detection coordinate system consistent with the design model based on the gear axis; In the detection coordinate system, the measured point cloud data is spatially aligned with the design model, and the normal distance from the point cloud to the model surface is calculated.

7. The high-precision injection molding gear water nozzle cutting method according to claim 6, characterized in that: Generating a quality report including flatness error and residual height specifically includes the following steps: Extract the point cloud within the first diameter range of the central area of ​​the cutting surface and calculate the flatness error ε = |zi - zavg|, where zi is the point cloud height value and zavg is the average height; Detect the residual nozzle height hr at the edge of the cutting surface. If there is a continuous area where hr> the allowed height, it will be marked as a residual defect; Integrate flatness error εf, residual height distribution map and residual defect markers to generate structured quality reports.

8. The high-precision injection molding gear cutting method according to claim 1, characterized in that: The generation of a quality report including flatness error and stub height may also include: The process database is updated according to the quality report and the processing force curve data, by optimizing the cutting parameters and outputting the process parameter optimization instructions to the subsequent processing batches.

9. A water nozzle device for injection molding gear, characterized in that: A high-precision injection molding gear water nozzle cutting method according to any one of claims 1 to 8 is adopted, wherein the injection molding gear water nozzle cutting device comprises a frame (100), wherein a scanning station (200), a transplanting mechanism (300), a cutting mechanism (400), a chamfering mechanism (500), a quality inspection mechanism (600) and a control cabinet (700) are sequentially integrated on the frame (100), and the control module is integrated in the control cabinet (700); The scanning station (200) is arranged in the middle of the frame (100), and is correspondingly integrated with a visual inspection system; The transfer mechanism (300) comprises a mechanical arm (301) for connecting the scanning station (200), the cutting mechanism (400) and the chamfering mechanism (500), and the mechanical arm (301) is provided with a product fixing cylinder (302), a Z-direction cylinder and an X-direction cylinder.

10. The injection molding gear water nozzle device according to claim 9, characterized in that: The cutting mechanism (400) comprises a servo-driven Z-axis slide (401) and a cutting spindle (402), wherein a tool (403) is mounted on the lower end of the cutting spindle (402); The chamfering mechanism (500) comprises a chamfering spindle (501) and a chamfering knife (502) arranged at the lower end of the chamfering spindle (501); the chamfering spindle (501) is integrated with an ultrasonic vibration unit; and an air shower assembly for cleaning is provided on one side of the chamfering mechanism (500).

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