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

Abstract

The application discloses a high-precision injection gear water gap cutting method and device, which comprises the following steps: moving an injection-molded gear blank to a scanning station by a manipulator; generating three-dimensional model data by three-dimensionally scanning a water gap region through a 3D scanner; extracting water gap height, diameter and position parameters; planning cutting depth and chamfer angle by a control module and generating self-adaptive cutting instructions; then driving a tool to execute cutting by a force feedback execution mechanism, simultaneously, a multi-dimensional force sensor monitors cutting resistance in real time, when the resistance exceeds a threshold, the feed speed is dynamically adjusted and processing force curve data is recorded; the cutting surface is scanned for the second time in the same station, a quality report containing flatness error and residual height is generated by comparing measured point cloud with a design model; water gap feature modeling is realized through three-dimensional scanning, cutting parameters are dynamically optimized in combination with real-time force feedback, the problems of overcutting or residual are solved, product yield is improved, production efficiency is significantly improved and production cost is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of injection molding, in particular to a high-precision injection molding gear water gap cutting method and device. BACKGROUND

[0002] Plastic gears have been widely used in the fields of automotive electronics, medical devices, precision instruments, etc. due to their lightweight, corrosion resistance, and low noise advantages. With the increasing precision requirements of industrial equipment, high-precision injection molding gears need to ensure that the tooth profile tolerance and the end face runout are less than or equal to 0.03 mm. Such gears generally use a middle point glue injection molding process to evenly spread the molten plastic from the center of the gear, significantly reducing the shrinkage anisotropy caused by differences in cooling rates. However, the water gap remaining in the center of the gear after injection molding needs to be precisely cut later, otherwise it will affect the gear assembly precision and transmission performance.

[0003] The current mainstream water gap cutting technology uses a fixed programmed processing device: the water gap is cut by presetting the tool stroke and feed speed (such as single gate method). This method has the following significant defects:

[0004] Water gap size fluctuations lead to uncontrollable cutting accuracy - due to injection molding process fluctuations (temperature and pressure changes), the actual height and diameter of the water gap have deviations, and fixed cutting parameters cannot dynamically adapt to the actual water gap geometry, resulting in overcut (damaging the gear base) or residual, with high product defect rates. Manual sampling intervention can partially alleviate the problem, but it severely restricts the production rhythm (increases the processing time of individual pieces) and cannot fundamentally solve the process consistency problem.

[0005] Therefore, there is a need to improve the existing water gap cutting technology to solve the problem of uncontrollable cutting accuracy of injection molding gears due to water gap size fluctuations. SUMMARY

[0006] The purpose of the present application is to provide a high-precision injection molding gear water gap cutting method and device to solve the above technical problems.

[0007] To achieve this purpose, the present application adopts the following technical solutions:

[0008] A high-precision injection molding gear water gap cutting method is executed by a cutting device linked with an injection molding machine, the cutting device includes a visual detection system, a control module, and a force feedback execution mechanism; the visual detection system includes a 3D scanner, and the tool spindle of the force feedback execution mechanism is integrated with a multi-dimensional force sensor; the water gap cutting method includes the following steps:

[0009] The injection molded gear blank is moved to the scanning station by a robot, the water gap area is scanned by the visual detection system, and a three-dimensional model data of the water gap is generated;

[0010] Extracting the height, diameter and position parameters of the water gap based on the three-dimensional model data, planning the cutting depth and chamfer angle through the control module, and generating adaptive cutting instructions;

[0011] The force feedback actuator drives the tool to cut the water gap according to the adaptive cutting instructions, and simultaneously monitors the cutting resistance in real time through a multi-dimensional force sensor, dynamically adjusts the feed speed when the resistance exceeds a preset threshold, and records the machining force curve data;

[0012] The cutting surface is scanned twice at the same station, the measured point cloud data is compared with the design model, and a quality report including the flatness error and residual height is generated.

[0013] Optionally, based on the three-dimensional model data, the height, diameter and position parameters of the water gap are extracted, the cutting depth and chamfer angle are planned through the control module, and adaptive cutting instructions are generated, specifically including the following steps:

[0014] The three-dimensional model data is subjected to point cloud filtering processing to remove environmental noise points and retain effective point cloud data in the water gap area;

[0015] Based on the effective point cloud data, the water gap center axis is fitted, and a cylindrical coordinate system is established based on the water gap center axis;

[0016] In the cylindrical coordinate system, the water gap cross section is layered and intercepted, and the equivalent diameter of each layer and the height value relative to the gear end face are calculated.

[0017] Optionally, after the water gap cross section is layered and intercepted in the cylindrical coordinate system, the equivalent diameter of each layer and the height value relative to the gear end face are calculated, and then the following steps are further included:

[0018] The control module extracts the maximum diameter Dmax of the water gap top, the minimum diameter Dmin of the root, and the total height H, and combines the position offset ΔP of the water gap center axis and the gear axis;

[0019] According to the formula: cutting depth Hcut = H × k1 - δ, the actual cutting depth is calculated, wherein k1 is a safety margin coefficient, 0.90≤k1≤0.98, and δ is a tool wear compensation value;

[0020] Based on Dmax, Dmin and ΔP, a spiral progressive tool path instruction and a chamfer angle θ generation rule are generated, and are compiled into adaptive cutting instructions.

[0021] Optionally, the generation rule of the chamfer angle θ is:

[0022] When the maximum diameter Dmax of the water gap top is less than 3mm, the chamfer angle θ is set to 45°;

[0023] When the maximum diameter Dmax of the top of the water gap is greater than or equal to 3 mm, the chamfer angle θ is set to 30°.

[0024] Optionally, the force feedback actuator drives the tool to cut the water gap according to the adaptive cutting instruction, simultaneously monitors the cutting resistance in real time through the multi-dimensional force sensor, dynamically adjusts the feed speed when the resistance exceeds the preset threshold, and records the machining force curve data, specifically including the following steps:

[0025] The helical progressive tool path, the cutting depth Hcut and the chamfer angle θ in the adaptive cutting instruction are analyzed, and the tool feed speed v0 is initialized;

[0026] The tool is driven to cut into the water gap along the helical progressive tool path, and the cutting resistance F is collected in real time through the multi-dimensional force sensor, and is decomposed into axial resistance Fz and radial resistance Fr;

[0027] When the axial resistance Fz exceeds the preset safety threshold interval [0.8Fn, 1.2Fn], the feed speed v is dynamically adjusted according to the function v = v0 × (Fn / Fz)k2, wherein Fn is the standard cutting force of the material, and k2 is the damping coefficient, 0.5≤k2≤1.0;

[0028] In the chamfering stage, the ultrasonic vibration tool is switched to vibrate cutting at a frequency of 20-40 KHz, and the fluctuation amplitude of the radial resistance Fr is monitored, and if the fluctuation value ΔFr>15%Fn, the tool wear warning is triggered;

[0029] The time-resistance curve data is recorded synchronously, and the machining force curve data including the axial resistance Fz, the radial resistance Fr and the adjusted feed speed v is generated.

[0030] Optionally, the same work station is scanned twice to compare the measured point cloud data with the design model, specifically including the following steps:

[0031] In the same work station where the cutting is completed, the visual detection system is controlled to perform a second three-dimensional scanning on the water gap surface to obtain measured point cloud data;

[0032] The measured point cloud data is processed in the coordinate system to establish a detection coordinate system consistent with the design model with the gear shaft center as the reference;

[0033] In the detection coordinate system, the measured point cloud data is spatially registered with the design model to calculate the normal distance from the point cloud to the model surface.

[0034] Optionally, the quality report including the flatness error and the residual height is generated, specifically including the following steps:

[0035] Extract the point cloud in the first diameter range of the center area of the cutting surface, calculate the flatness error ε = |zi - zavg|, where zi is the height value of the point cloud, and zavg is the average height;

[0036] Detect the residual gate height hr of the cutting surface edge, and if there is a continuous area hr> allowed height, mark it as a residual defect;

[0037] Integrate the flatness error εf, the residual height distribution map and the residual defect mark to generate a structured quality report.

[0038] Optionally, the quality report including flatness error and residual height, then also includes:

[0039] According to the quality report and the machining force curve data, update the process database, optimize the cutting parameters, and output the process parameter optimization instruction to the subsequent machining batch.

[0040] The application also provides a water gate cutting device for injection molded gears, which adopts the high-precision water gate cutting method for injection molded gears as described above, and comprises a rack, wherein a scanning station, a transplanting mechanism, a cutting mechanism, a chamfering mechanism, a quality inspection mechanism and a control cabinet are sequentially integrated on the rack, and a control module is integrated in the control cabinet.

[0041] The scanning station is arranged in the middle part of the rack and is correspondingly integrated with a visual detection system.

[0042] The transplanting mechanism comprises 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.

[0043] Optionally, the cutting mechanism comprises a servo-driven Z-axis sliding table and a cutting spindle, and the lower end of the cutting spindle is provided with a cutter.

[0044] The chamfering mechanism comprises a chamfering spindle and a chamfering cutter arranged at the lower end of the chamfering spindle, the chamfering spindle is integrated with an ultrasonic vibration unit, and one side of the chamfering mechanism is provided with an air shower assembly for cleaning.

[0045] Compared with the prior art, the present application has the following beneficial effects: firstly, the injection molded gear blank is moved to the scanning station by the mechanical hand, the water gap area is scanned by the 3D scanner to generate three-dimensional model data; based on the three-dimensional model data, the water gap height, diameter and position parameters are extracted, the control module plans the cutting depth and the chamfer angle and generates the adaptive cutting instruction; then the force feedback actuator drives the cutter to execute cutting, and the multi-dimensional force sensor monitors the cutting resistance in real time, and 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 again in the same station, the quality report containing the flatness error and the residual height is generated by comparing the measured point cloud with the design model, and the complete process closed loop from detection to feedback is formed; the present method realizes the water gap feature modeling through three-dimensional scanning, dynamically optimizes the cutting parameters combined with real-time force feedback, and solves the overcut or residual problem caused by water gap size fluctuation in traditional fixed program processing; the secondary scanning quality inspection link is directly related to the design model, which ensures that the cutting surface has flatness error and no residual water gap, improves the product yield, significantly improves the production efficiency and reduces the comprehensive cost. BRIEF DESCRIPTION OF DRAWINGS

[0046] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor.

[0047] The structures, proportions, sizes, etc. shown in the drawings of the present specification are only used to cooperate with the content disclosed in the present specification, to be understood and read by those skilled in the art, and do not have technical significance to limit the conditions that the present application can be implemented. Any modification of structure, change of proportion relationship or adjustment of size, which does not affect the effects and purposes that the present application can produce, should still fall within the scope of the technical content disclosed by the present application.

[0048] Figure 1 Production actual product schematic diagram of the high-precision injection molded gear water gap cutting method of the present embodiment one;

[0049] Figure 2 Main body structure schematic diagram of the injection molded gear water gap cutting device of the present embodiment one; Figure 1 A-A cross-sectional structure schematic diagram;

[0050] Figure 3 Overall structure schematic diagram of the injection molded gear water gap cutting device of the present embodiment two;

[0051] Figure 4 Main body structure schematic diagram of the injection molded gear water gap cutting device of the present embodiment two;

[0052] Figure 5 Fig. 1 is a schematic structural diagram of a transplanting mechanism of a water gap cutting device for injection molded gear of the second embodiment.

[0053] Fig. 1 is a schematic structural diagram of a transplanting mechanism of a water gap cutting device for injection molded gear of the second embodiment. DETAILED DESCRIPTION

[0054] In order to make the purpose, features and advantages of the present application more obvious and easy to understand, the technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the following described embodiments are only some of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0055] In the description of the present application, it should be understood that the terms "upper", "lower", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. It should be noted that when a component is considered to be "connected" to another component, it can be directly connected to the other component or there can be a component disposed therebetween.

[0056] The technical solutions of the present application will be further described below in conjunction with the drawings and through specific embodiments.

[0057] Embodiment I:

[0058] The embodiment of the present application provides a high-precision injection molded gear water gap cutting method, which is executed by a cutting device linked with an injection molding machine. The cutting device includes a visual detection system, a control module and a force feedback execution mechanism. The visual detection system includes a 3D scanner, and the tool spindle of the force feedback execution mechanism is integrated with a multi-dimensional force sensor. The water gap cutting method includes the following steps:

[0059] S1, the injection molded gear blank is moved to the scanning station by the manipulator, the water gap area is scanned by the visual detection system, and the three-dimensional model data of the water gap is generated. Combined with the three-dimensional model data of the water gap, the three-dimensional model data of the gear is scanned by the visual detection system, and the three-dimensional model data of the gear is generated. Figure 1 and Figure 2The actual three-dimensional model in the present scheme is shown.

[0060] S2, based on the three-dimensional model data, the height, diameter and position parameters of the water gap are extracted, the cutting depth and the chamfer angle are planned by the control module, and the adaptive cutting instruction is generated; based on the point cloud data, the height, diameter and position offset of the water gap are extracted, and the cutting depth and chamfer angle are dynamically planned by the algorithm.

[0061] S3, the force feedback actuator drives the cutter to cut the water gap according to the adaptive cutting instruction, and simultaneously monitors the cutting resistance in real time through the multi-dimensional force sensor, dynamically adjusts the feed speed when the resistance exceeds the preset threshold, and records the machining force curve data.

[0062] S4, the cutting surface is scanned again in the same station, the measured point cloud data is compared with the design model, and the quality report including the flatness error and the residual height is generated. Avoid positioning error caused by transplanting, realize machining-quality inspection integration.

[0063] S5, according to the quality report and the machining force curve data, the process database is updated, the cutting parameters are optimized, and the process parameter optimization instruction is output to the subsequent processing batch.

[0064] The working principle of the present application is as follows: first, the gear blank molded by injection molding is moved to the scanning station by the manipulator, the three-dimensional model data is generated by three-dimensional scanning of the water gap area through the 3D scanner; based on the three-dimensional model data, the height, diameter and position parameters of the water gap are extracted, the cutting depth and chamfer angle are planned by the control module and the adaptive cutting instruction is generated; then the force feedback actuator drives the cutter to execute cutting, and the multi-dimensional force sensor monitors the cutting resistance in real time, dynamically adjusts the feed speed when the resistance exceeds the threshold, and records the machining force curve data; the cutting surface is scanned again in the same station, the measured point cloud is compared with the design model to generate the quality report containing the flatness error and the residual height, forming a complete process closed loop from detection to feedback; the present method realizes water gap feature modeling through three-dimensional scanning, dynamically optimizes the cutting parameters combined with real-time force feedback, solves the overcut or residual problem caused by water gap size fluctuation in traditional fixed program machining; the secondary scanning quality inspection link is directly related to the design model, ensures the flatness error of the cutting surface and no residual water gap, improves the product yield, significantly improves the production efficiency and reduces the comprehensive cost.

[0065] In the present embodiment, it is specifically explained that step S2 specifically comprises the following steps:

[0066] S21, the point cloud filtering processing is performed on the three-dimensional model data, the environmental noise points are removed and the effective point cloud data of the water gap area is retained; the environmental noise (such as injection flash, dust reflection) is removed by the outlier rejection algorithm, and the effective point cloud of the main body of the water gap is retained.

[0067] S22, fitting the water gap center axis based on the effective point cloud data, establishing a cylindrical coordinate system based on the water gap center axis; fitting the water gap center axis based on the least square method, establishing a cylindrical coordinate system with the axis as the Z axis, eliminating the measurement reference error caused by the water gap deflection, and providing a unified reference for layered calculation.

[0068] S23, layering and intercepting the water gap cross section under the cylindrical coordinate system, calculating the equivalent diameter of each layer section and the height value relative to the gear end face. The cross section is intercepted along the axis direction at a fixed interval (usually 0.1mm), and the equivalent diameter (area equivalent circle diameter) of each layer section is calculated. The water gap taper change characteristics are captured to support accurate cutting amount planning.

[0069] S24, the control module extracts the maximum diameter Dmax of the water gap top, the minimum diameter Dmin of the root, and the total height H, and combines the position offset ΔP of the water gap center axis and the gear axis; from the layered data, the maximum diameter Dmax of the top (which affects the chamfer design), the minimum diameter Dmin of the root (which is related to the cutting resistance), the total height H (which determines the cutting depth), and the axis offset ΔP (which reflects the positioning error) are extracted. Quantify the core parameters of injection fluctuation to provide input for adaptive control.

[0070] S25, according to the formula: cutting depth Hcut=H×k1-δ; calculate the actual cutting depth, where k1 is the safety margin coefficient, 0.90≤k1≤0.98, and δ is the tool wear compensation value.

[0071] According to the formula Hcut=H×k1-δ to calculate the actual cutting depth, where:

[0072] k1 (safety margin coefficient): reserve 5%-10% margin to prevent overcutting;

[0073] δ (tool wear compensation): dynamically corrected according to historical wear data (such as 0.05mm compensation for every 100 pieces processed); balance processing safety and efficiency, avoid residual or substrate damage caused by fixed depth.

[0074] S26, generate spiral progressive tool path instructions based on Dmax, Dmin and ΔP, and generate rules for chamfer angle θ, and compile into adaptive cutting instructions.

[0075] Generate spiral progressive tool path based on Dmax, Dmin and ΔP:

[0076] Small diameter water gap (Dmin<2mm) uses high speed and small feed;

[0077] Large offset (ΔP>0.1mm) increases radial compensation path;

[0078] And based on Dmax setting chamfer angle θ (see the following rules), the cutting path and process parameters are optimized.

[0079] In this embodiment, the generation rule of chamfer angle θ is further illustrated as follows:

[0080] When the maximum diameter Dmax of the nozzle top is less than 3mm, the chamfer angle θ is set to 45°; small nozzle uses large chamfer to disperse edge stress and avoid gear center fragmentation.

[0081] When the maximum diameter Dmax of the nozzle top is greater than or equal to 3mm, the chamfer angle θ is set to 30°. Large nozzle limits chamfer angle to prevent excessive cutting from weakening the strength of the shaft hole.

[0082] Through the diameter-related chamfer rule, a balance is achieved between deburring requirements and structural integrity, solving the problem of stress concentration or insufficient strength caused by traditional fixed angle.

[0083] In this embodiment, it is specifically illustrated that step S3 specifically comprises the following steps:

[0084] S31, analyze the helical progressive tool path, cutting depth Hcut and chamfer angle θ in the adaptive cutting instruction, and initialize the tool feed speed v0;

[0085] Analyze the generated adaptive cutting instruction, load the helical progressive tool path, cutting depth Hcut and chamfer angle θ. Initialize the feed speed v0 based on the default value of the material library (such as POM plastic set to 150mm / min), to ensure that the cutting action is strictly synchronized with the planned parameters.

[0086] S32, drive the tool to cut into the nozzle along the helical progressive tool path, and simultaneously collect the cutting resistance F in real time through the multi-dimensional force sensor, and decompose it into axial resistance Fz and radial resistance Fr;

[0087] When the tool cuts into the nozzle along the helical path, the 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 the tool deflection). Multi-dimensional monitoring of the machining state is realized, which provides a basis for dynamic adjustment.

[0088] S33, when the axial resistance Fz exceeds the preset safety threshold interval [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, and 0.5≤k2≤1.0; solve the cutting risk caused by abnormal material hardness.

[0089] When Fz exceeds the safety threshold [0.8Fn, 1.2Fn] (Fn is the material standard cutting force), the feed speed is adjusted according to the function v=v0x(Fn / Fz)k2:

[0090] Fz is too high (>1.2Fn): reduce speed to prevent chipping (k2=1.0 for maximum reduction);

[0091] Fz is too low (<0.8Fn): increase speed to improve efficiency (k2=0.5 for gentle response).

[0092] S34, switch to ultrasonic vibration tool during chamfering stage, vibrate cutting at a frequency of 20-40KHz, and monitor the fluctuation amplitude of radial resistance Fr, if the fluctuation value ΔFr>15%Fn, trigger tool wear warning.

[0093] S35, synchronously record time-resistance curve data, generate machining force curve data including axial resistance Fz, radial resistance Fr and adjusted feed speed v.

[0094] In this embodiment, it is specifically explained that step S4 specifically comprises the following steps:

[0095] S41, in the same station where cutting is completed, control the visual detection system to perform secondary three-dimensional scanning on the cut water gap surface to obtain measured point cloud data;

[0096] Directly trigger secondary scanning in the station where cutting is completed to avoid positioning deviation caused by transplanted. The 3D scanner obtains measured point cloud of the cutting surface, ensures that the detection reference and the machining reference are strictly consistent, and eliminates repeated positioning error.

[0097] S42, perform coordinate system alignment processing on the measured point cloud data, and establish a detection coordinate system consistent with the design model with the gear shaft center as the reference;

[0098] The detection coordinate system is established with the gear shaft center as the origin, the measured point cloud and the design model coordinate system are aligned through feature matching, and the detection distortion problem caused by gear clamping deflection is solved.

[0099] S43, in the detection coordinate system, perform spatial registration of the measured point cloud data and the design model, and calculate the normal distance from the point cloud to the model surface. The measured point cloud and the design model surface are registered by ICP (iterative closest point), the normal distance of each point to the model surface is calculated, and the cutting surface topography deviation is quantified.

[0100] S44, extract the point cloud in the first diameter range of the center region of the cutting surface, calculate the flatness error ε=|zi-zavg|, where zi is the point cloud height value, and zavg is the average height.

[0101] S45, detect the height of the residual gate edge of the cutting surface, and if there is a continuous area hr> allowed height, mark it as a residual defect; detect the height of the residual gate edge of the cutting surface, and if there is a continuous area hr> 0.1 mm (assembly gap tolerance limit), mark it as a residual defect.

[0102] S46, integrate the flatness error εf, the residual height distribution map and the residual defect mark to generate a structured quality report. Integrate the flatness error εf, the residual height distribution map (color block diagram) and the defect mark to generate a readable quality report.

[0103] Example two:

[0104] In combination Figures 3 to 5 As shown in the figure, the application also provides a gear injection gate cutting device, which adopts the high-precision gear injection gate cutting method of example one. The gear injection gate cutting device includes a rack 100, which is sequentially integrated with 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. The control module is integrated in the control cabinet 700. The scanning station 200 is arranged in the middle of the rack 100, and a visual detection system is correspondingly integrated.

[0105] The transplanting mechanism 300 includes a mechanical arm 301 for connecting the scanning station 200, the cutting mechanism 400 and the chamfering mechanism 500. The mechanical arm 301 is provided with a product fixing cylinder 302, a Z-direction cylinder 303 and an X-direction cylinder 304.

[0106] When working, the gear blank is moved by the mechanical arm 301 to the scanning station 200, and a 3D visual system generates a gate three-dimensional model. The control cabinet 700 plans a cutting instruction based on the model data, drives the transplanting mechanism 300 to grab the workpiece by 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-direction cylinder. Finally, the quality inspection mechanism 600 is triggered in the same station for secondary scanning, and a quality report is generated and fed back to the control cabinet 700.

[0107] In this embodiment, the cutting mechanism 400 includes a servo-driven Z-axis sliding table 401 and a cutting spindle 402, and the lower end of the cutting spindle 402 is provided with a cutter 403. The chamfering mechanism 500 includes a chamfering spindle 501 and a chamfering cutter 502 arranged at the lower end of the chamfering spindle 501. The chamfering spindle 501 is integrated with an ultrasonic vibration unit, and one side of the chamfering mechanism 500 is provided with a wind shower assembly 503 for cleaning.

[0108] The above-described embodiments are only used to illustrate the technical solutions of the present application, and are not intended to limit the present application; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that the technical solutions recorded in the foregoing embodiments can still be modified, or some technical features can be replaced by equivalent replacements; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A high-precision injection molding gear cutting method, which is performed by a cutting mechanism linked to an injection molding machine, characterized in that: The cutting mechanism 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 a scanning station (200) by a robot arm, 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; specifically, the following steps are included: 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; Cut the nozzle cross section layer by layer in the cylindrical coordinate system, and calculate the equivalent diameter of each layer and the height relative to the gear end face; 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, a spiral progressive tool path instruction and a generation rule for the chamfer angle θ are generated and compiled into an adaptive cutting instruction; wherein the generation rule for 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 3mm, set the chamfer angle θ to 30°; 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 20-40kHz, 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; Synchronously record the time-resistance curve data to generate machining force curve data including axial resistance Fz, radial resistance Fr and adjusted feed speed v; 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 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.

3. The high-precision injection molding gear water nozzle cutting method according to claim 2, 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 ε, residual height distribution map and residual defect markers to generate structured quality reports.

4. 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.

5. A nozzle device for injection molding gear, characterized in that: A high-precision injection molding gear water-cutting method according to any one of claims 1 to 4 is adopted, wherein the injection molding gear water-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 on the upper part of the frame (100) and is integrated with a visual detection 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.

6. The injection molding gear water nozzle device according to claim 5, 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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