最新刊期
期 10 ， 2020
- 摘要：In order to solve the problem that the coloring style of curvic coupling is not up to standard due to tooth profile error， it is difficult to quickly identify the root cause of the problem and it is difficult to adjust the process parameters， a digital closed-loop manufacturing technology of curvic coupling is proposed. Based on the machining principle of curvic coupling， the mathematical model of theoretical tooth surface is established， and the spatial coordinates and normal vector of each point are calculated by discretization of tooth surface. Based on the mathematical model of tooth surface， the correction method of tooth profile error is established. By using the method of Tikhonov regularization and L Curve to solve linear system of equations， the adjustment parameters of machine tool and grinding wheel parameters could be obtained to correct the tooth profile error. The test results show that the digital closed-loop manufacturing technology can accurately identify the root cause of the problem of unqualified workpiece and give the corresponding correction. The maximum tooth profile error of the test workpiece is corrected from 14.3 μm to 3 μm， and the colored contact zone detection meets the inspection standard. Through the digital closed-loop manufacturing technology， the accuracy and machining efficiency of gear pair tooth surface can be effectively improved， and the digitization and intelligence of manufacturing process is also realized.关键词：Curvic coupling;Tooth profile error;Error correction;Digital closed-loop manufacturing;Tooth surface accuracy
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发布时间：2022-11-10 - 摘要：Aiming at the problems of low efficiency and imperfect test scheme of the existing accelerated life test of the harmonic reducer， a double stress step-down accelerated life test method is proposed. Taking the harmonic reducer for industrial robots as the research object， through comparing the acceleration schemes and analyzing the failure mechanism of accelerated life， a double stress step-down test load spectrum is formulated. Based on the iterative relationship between the step-down load stresses of each segment， the optimal parameters of Weibull distribution of harmonic driver are calculated by genetic algorithm. The results show that the acceleration factor for this double stress step-down life test is 12.5. The test efficiency is accurately and effectively improved by this scheme， and a reference for optimizing the design of the harmonic reducer and shortening the test cycle of the accelerated life test of the harmonic reducer are provided.关键词：Harmonic reducer;Double stress step-down acceleration;Load spectrum;Genetic algorithm;Weibull distribution
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发布时间：2022-11-10 - 摘要：The formation mechanism of tooth surface twist in helical gear generating machining （worm grinding and hobbing） and the measure to reduce the tooth surface twist are mainly studied. Based on the diagonal worm grinding or hobbing machining method， the tooth surface equation of helical gears with axial modification is constructed. The standard helical gear tooth surface and the helical gear machining tooth surface with axial modification are compared to obtain the correlation law between the speed ratio of axial feed and diagonal feed of the generating tool （worm or hob） and tooth surface twist. Based on the derived tooth surface equation of the helical gear with axial modification， Matlab and CATIA combined modeling technology is used to establish a three-dimensional geometric model of the helical gear pair with axial modification. The simulation analysis of the meshing performance of the gear pairs with different levels of tooth surface twist shows the influence of tooth surface twist on the meshing performance. The research shows that， the larger the helix angle of helical gear with axial modification is， the more serious the tooth surface twist is. Modification amount does not affect the twist of the tooth surface. The ratio of the axial feed and diagonal feed of the tool has the best match with the tooth surface twist. Improved tooth surface twist can effectively reduce the transmission error and improve the gear carrying capacity. The CAD/CAE integrated modeling and analysis method based on the combination of Matlab， CATIA and finite element commercial software provides methods and tools for the research on tooth surface twist of helical gears with axial modification.关键词：Diagonal hobbing;Axial modification;Helical gear;Tooth surface twist;Meshing performance
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发布时间：2022-11-10 - 摘要：Based on the tooth surface equation of the Variable hyperbolic circular-arc-tooth-trace （VH-CATT）， the gear meshing principle is used to analyze the tooth surface contact during the meshing process， the positions distribution of the VH-CATT meshing point during meshing process of the concave and convex tooth surface is obtained. According to the principles of gear geometry， the formulas for calculating the important parameters of EHL such as the principal curvatures and entrainment velocity of the VH-CATT meshing point during meshing process of the concave and convex tooth surface is obtained. The Downson-Higginson minimum film thickness model is used to analyze the minimum film thickness of EHL in the VH-CATT meshing process， and the variation rules of EHL minimum film thickness in the meshing process of gear pairs with different gear design parameters are obtained. Theoretical analysis shows that the lubrication condition between the dedendum of driver gear （the concave tooth surface） and the addendum of driven gear （the convex tooth surface） of VH-CATT is the worst， where the wear failure of tooth surface is most likely to occur. When the input load increases， the minimum film thickness decreases slightly， and the gear is provided with the characteristics of impact load resistance. With the increase of pressure angle， the minimum film thickness increases so that the lubricity and bearing capacity are improved. When the tooth trace radius becomes longer， the minimum film thickness decreases slightly， selecting a reasonable cutter head radius to process the gear can improve the lubricity. The results provide a theoretical basis for the lubrication design and wear calculation of VH-CATT.关键词：Variable hyperbolic circular-arc-tooth-trace（VH-CATT）;Contact analysis;Elastohydrodynamic lubrication（EHL）;Minimum film thickness
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发布时间：2022-11-10 - 摘要：In order to understand the inherent vibration characteristics of multi-motor parallel drive-transmission system， and reveal the influence of system stiffness parameters on its natural frequency， considering the nonlinear factors such as time-varying meshing stiffness and messing error， the coupling dynamics model of multi-motor parallel drive-transmission system is established by using lumped-mass method. According to the trait of the vibration displacement of center components， the three typical low-order vibration modes are given， that is， torsional vibration mode， transverse vibration model and planet vibration mode. Then， the influence of meshing stiffness and support stiffness on the natural frequencies is studied. The results show that the other frequency components are sensitive to the change of system stiffness parameters except high order frequencies， and the coupling effect of system should be taken into full account when solving the natural frequency of the system. Meanwhile， the mode jumping will occur when the system stiffness parameters change， namely， a sudden change in the vibration mode of system， and it increases the complexity of the dynamic behavior of the system. Therefore， in the process of dynamic design， the mode jumping point should be avoided as much as possible to prevent the multi-order resonance from occurring.关键词：Multi-motor parallel drive-transmission system;Natural frequency;Vibration mode;Mode jumping
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发布时间：2022-11-10 - 摘要：Sparse representation has a wide range of applications in the field of image processing and audio processing. Applying the sparse representation theory to the field of vibration signal processing can efficiently represent the periodic components of the signal. Through the Adams system simulation and measured signal rotor coupling fault data sparse representation， the vibration characteristics of rotor unbalance bearing coupling fault and the law of interaction between faults are studied under the sparse representation. The results show that bearing faults are usually submerged under coupled faults， and it exhibits weak fault characteristics compared to unbalanced faults. Aiming at the problem that the bearing fault feature is difficult to extract in the rotor unbalance bearing coupling fault， using the sparse representation method based on Gabor atom to match the periodic vibration component in the rotor unbalance bearing coupled fault vibration signal， and the spectral kurtosis algorithm is used to find the frequency band where the impact signal is located for bearing fault feature extraction. The effectiveness of the proposed method is verified by analyzing multiple sets of measured signals.关键词：Sparse representation;OMP algorithm;Fault diagnosis;Vibration signal processing;Coupling fault
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发布时间：2022-11-10 - 摘要：The translation and torsion coupled strong nonlinear dynamics model of two-stage planetary gear transmission system is established， and the nonlinear factors such as time-varying meshing stiffness， tooth side clearance and meshing error are introduced， after dimensionless treatment， dynamics equations are established. By using the numerical integration method， system of equations are solved， the nonlinear dynamic response result of the system is obtained， and the bifurcation diagram of the system changing with excitation frequency in the case of different backlash is calculated. Through comprehensive use of phase trajectory， Poincare section and Lyapunov index spectrum， and the system correlation dimension is obtained by the G-P algorithm. The nonlinear dynamics characteristic of two-stage planetary system is studied from the perspective of qualitative and quantitative， the influence of chaotic frequency， into the way of chaos and backlash of two-stage planetary system on the nonlinear characteristics of two-stage planetary gear train is obtained. Some theoretical basis for the study of fault mechanism of two-stage planetary gear system is provided.关键词：Two-stage planetary gear system;Lyapunov index;Translation-torsion coupling;Nonlinear dynamics;Bifurcation;Chaos
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发布时间：2022-11-10
Theory·Reserach
- 摘要：According to the nutation motion principle，a new single-stage double circular-arc spiral bevel gear nutation reducer with simple structure and large transmission ratio is designed， and its transmission ratio calculation formula is obtained. With the minimum volume of the nutation reducer as the objective function，an optimization mathematical model is established with 4 design variables and 12 optimization constraints，and the relevant parameters of the single-stage nutation bevel gear are obtained. According to the optimized parameters of gear， the three-dimensional model of the nutation bevel gear is established，and its finite element loading strength is analyzed. The results show that the contact area of single-stage nutation bevel gear is large because there are many teeth and concave-convex tooth surfaces in contact at the same time，the Mises stress distribution on the internal and external bevel gears is uniform，but the stress value at the top of the small end of the external bevel gear is larger. The research results are of great significance to the further improvement of single-stage double circular-arc spiral bevel gear nutation reducer.关键词：Single-stage nutation reducer;Optimal design;Spiral bevel gear
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发布时间：2022-11-10 - 摘要：The meshing performance of enveloping tours worm drive requires the envelope lines to be matched strictly in accordance with the established relationship， the accuracy of tooth profile will directly affect its application performance. Aiming at the complicate meshing surface representation issue of cone-generated enveloping torus worm， the digital modeling method of this worm is proposed. The modeling frame is established firstly， and the meshing equations of the working tooth profile in different coordinate systems for the worm are deduced by applying differential geometry， kinematics， envelope theory and space coordinate transformation method， and the digital models of the working tooth profile of the worm are established， simultaneously， the generatrices equation of bottom and addendum surface are worked out. In addition， the constraint conditions of the worm digital models are constructed according to the enveloping process and boundary conditions of tooth profile. The solving algorithm for the complex nonlinear mathematical models is also designed based on the forming principle of the envelope surface， the instantaneous contact line and all meshing point cloud for the tooth profile are calculated， the distribution of contact line of worm tooth profile is also given. The digital solid model of worm is obtained by using curve and surface fitting technology based on the point cloud of worm tooth profile. The modeling experiment demonstrate that the digital model of worm is accurate， the designed solving algorithm of the model is effective as well as convergence， the worm tooth profile is of high precision， and the error of the worm tooth profile is at the level of 10-9. The research results can lay an accurate model foundation for precision digital manufacturing of cone-generated envelope torus worm and corresponding cone-generated double-envelope worm gear hob.关键词：Cone-generated torus worm;Meshing surface;Digital model;Algorithm
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发布时间：2022-11-10 - 摘要：Aiming at the problems of low calculation efficiency and singularity in the traditional D-H method and spinor method for robot kinematics analysis， the kinematics parameters of sewing robot are solved by using double quaternion. The kinematics equations of the sewing robot in double quaternion form are established， and the Dixon resultant is constructed using the elimination method to solve the kinematic parameters. The kinematics simulation is performed in a limited working range. The simulation results show that the method has high computing efficiency， which is about 10% faster than the D-H method， and can provide a theoretical basis for the motion control of the robot textile sewing process.关键词：Quaternion method;Double quaternion method;Dixon elimination;Sewing robot;Kinematics;Workspace
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发布时间：2022-11-10 - 摘要：The distribution of stress intensity factor and J integral of helical gear with three-dimensional crack under different initial crack parameters is studied. The finite element software is used to analyze the helical gear with initial crack. Three types of stress intensity factors and J integral at the elliptical crack tip of the dedendum are simulated and solved. The variation of the three stress intensity factors and J integral with the crack length， crack angle， crack position and other initial crack parameters is analyzed. The results show that when the data of different initial crack parameters are changed， the curves of the corresponding three stress intensity factors and J integral have obvious changing rules.关键词：Helical gear;Crack;Stress intensity factor;J integral
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发布时间：2022-11-10 - 摘要：For trajectory tracking control of a dual-arm space robot with uncontrolled base position and controlled base attitude in task space， an optimal control method based on state dependent Riccati equation （SDRE） is proposed. Firstly， based on the kinematics equation and fully driven dynamics equation of dual-arm space robot in joint space， the underactuated dynamics equation and the Jacobian relationship between the joint and the end of the manipulator are derived. Then， the SDC （state dependent coefficient） matrix is constructed by increasing the state variables， and the optimal tracking controller is designed based on the SDRE control theory， thus the trajectory tracking of the end grab and the base attitude of the dual-arm space robot is realized under the premise of optimizing the output torque energy. Finally， the Lyapunov method is used to prove the asymptotic stability of the system， and the effectiveness of the designed controller is verified by simulation experiments.关键词：Attitude control;Dual-arm space robot;Task space;State dependent Riccati equation（SDRE）;Optimal trajectory tracking control
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发布时间：2022-11-10 -
Design and Optimization of Trapezoidal Steering Mechanism based on Improved Particle Swarm Algorithm
摘要：In order to make the steering mechanism characteristic curve of the wheeled mobile robot closer to the ideal Ackerman steering characteristic curve and achieve precise steering purpose， the design and parameter optimization of its steering mechanism are optimized. The design of the trapezoidal steering mechanism and its effect on the mobile robot are studied， and the nonlinear optimization model of the trapezoidal steering mechanism is established. The traditional particle swarm optimization algorithm is introduced into the adaptive weights and Lagrange interpolation method to improve the algorithm. The method of solving the optimization model of nonlinear steering mechanism is given， the M-file of Matlab R2018b with improved particle swarm algorithm and solving the nonlinear model is written to analyze the optimization of steering mechanism. The angle of the knuckle arm and wheel， the angle of the triangle rocker arm and the chassis， the size of the triangle rocker arm and the knuckle arm are determined. The results of the optimized steering mechanism are close to the ideal Ackerman steering mechanism. Finally， the optimized steering mechanism is verified by an example. The experimental results are consistent with the actual application requirements. The error between the trajectory of the steering mechanism and the ideal running trajectory can be effectively reduced， and the maneuverability and track control of the mobile robot can be improved.关键词：Wheeled mobile robot;Steering mechanism;Improved particle swarm optimization;Matlab;Optimized design- 3
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发布时间：2022-11-10 - 摘要：The inverse kinematics solution of the traditional 6-axis robot requires position information and attitude information. Aiming at the problem of difficulty and uncertainty of object attitude recognition， a 6-axis robot attitude solution algorithm based on object position information is proposed. Based on the concept of robot dexterity， a service ball model for the robot's 5th axis is established， and the end positions of the robot are discretized to obtain a series of discrete points on the service sphere. Based on the conformal geometry of the robot， the mapping relationship between the discrete points and the joint angle of the robot is studied， and the attitude set of the robot at a certain spatial position is obtained. According to the comprehensive criteria of robot singularity， joint avoidance and joint continuity， a set of best robot poses is selected from the pose set. In the Cartesian coordinate system， interpolation of different position points is performed， and the continuous motion between different position points of the robot is realized by solving the pose of different interpolation points. The results show that， according to the three-dimensional coordinate information of the object， the inverse kinematics calculation of the 6-axis robot can be completed and the calculation speed is fast and the accuracy is high， which simplifies the attitude recognition process of the object and improves the efficiency of the robot's continuous operation.关键词：Inverse kinematics;Dexterity;Conformal geometry;Attitude
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发布时间：2022-11-10
Design· Calculation
- 摘要：In order to study the meshing stiffness of variable hyperbolic arc gear， the tooth surface equation of variable hyperbolic arc gear is obtained according to the forming principle， and its accurate three-dimensional model is established. Based on the theory of contact finite element analysis， the calculation method of meshing stiffness is studied. Using the finite element software， a pair of gear finite element model is constructed. The comprehensive elastic deformation of the tooth surface is extracted， and the normal contact force of the tooth surface is calculated by the torque formula. The single tooth mesh stiffness and the double tooth comprehensive mesh stiffness are calculated， which the results show that the stiffness curve of single tooth mesh increases first and then decreases with the increase of driving wheel angle. Then， the influence of different loads on the meshing stiffness curve is analyzed. The results show that the peak value of the stiffness curve increases with the increase of the load， and the load has more obvious influence on the peak value of the comprehensive meshing stiffness curve of the double teeth. At last， the influence of different tooth radius on the meshing stiffness curve is analyzed. The results reveal that the peak stiffness curve decreases with the increase of tooth radius， and the stiffness difference between the meshing area of single and double teeth decreases.关键词：Variable hyperbolic arc gear;Contact analysis;Mesh stiffness;Finite element method
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发布时间：2022-11-10 - 摘要：Aiming at the problem of the helical gears meshing which lead to the fatigue damage and shock of the gear surface， the dynamic performance and modification are analyzed and studied. The dynamics model of helical gears meshing is built based on the impact is affected by the backlash. The coupled model of rigid and flexible is built by Adams， and the angular velocity and load torque of the gear are obtained. Then， the finite element model of helical gear is established， the position and the curve of the maximum contact stress of are obtained. Finally， the angular acceleration， load torque and stress variation curve of the driven gear after modification are obtained by using the arc modification method. The research results indicate that the contact strength is improved based on the short-modification， which can provide the basis for gears analysis， such as， the fatigue life and the transmission efficiency.关键词：Fatigue damage;Dynamic performance;Backlash;Arc modification
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发布时间：2022-11-10 - 摘要：Construction vehicles have high requirements for load carrying capacity， with suspension stiffness large， vibration damping performance poor， and working environment harsh， severe vibration in the three directions of vertical， pitch and roll， which seriously affects the physical and mental health of the driver and the vehicle operational stability. To solve this problem， a 2-SPS+SR multi-dimensional vibration-damping suspension for construction vehicle seats is proposed. Firstly， the degree of freedom analysis of two translations and one rotation of the seat suspension is carried out by using the single-open chain theory. Then， the position equation of the seat suspension is established to analyze the position of the seat suspension， and the positive solution is given for the suspension structure. The first and second order motion coefficients of the suspension are obtained by taking the first and second derivatives of the position equation. Finally， the simulation analysis is performed in Adams/view and programming simulation of mathematical model is performed in Matlab to verify the correctness of the established mathematical and theoretical analysis. The results of analysis provide important significance for the study of the control simulation of the suspension and the research on the ride comfort of the construction vehicle on the three-dimensional road in the later period.关键词：Construction vehicle;Seat suspension;Multi-dimensional vibration reduction;Kinematics analysis
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发布时间：2022-11-10 - 摘要：The numerical analysis method is used to establish the one-way fluid structure coupling model of sliding bearing with oil seal edge structure， and the sliding bearing lubrication performance and bearing pad deformation are analyzed at different speeds. The results show that the oil film bearing capacity， pressure peak value， temperature and wall shear stress of the sealed oil edge sliding bearing are higher than unsealed oil seal edge sliding bearing， gas phase volume fraction， friction factor and outlet leakage flow are all smaller than oil unsealed edge sliding bearings， and the oil film bearing capacity， pressure peak and temperature are increased with the increase of rotating speed. The deformation of sliding bearing bush is mainly affected by temperature， the deformation of bearing pad with oil sealing edge is larger than without oil sealing edge， and the deformation of bearing bush are increased with the increase of rotating speed.关键词：Fluid structure coupling;Oil seal edge;Lubricating property;Deformation
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发布时间：2022-11-10 - 摘要：In order to improve the vibration and noise of automobile gearbox， by using the Romax， a dynamics model of the transmission drive system is established， and the dynamic bearing force during the operation of the gearbox is obtained by simulation. The modal analysis is performed on the built finite element box model to learn the box relatively weak areas. The dynamic force of the bearing simulation is used as the excitation of the shell vibration response analysis to analyze the shell vibration characteristics， the shell vibration acceleration is used as the boundary condition， and based on the shell acoustic boundary element model， the modal acoustics transfer method is used to calculate the radiated noise from the sound field outside the casing. By analyzing the modal participation factor and the modal acoustic contribution， the modals which contribute more to vibration noise are determined， and optimization is performed in the corresponding modal vibration sensitive place. The results show that the vibration noise of the optimized gearbox decreases and the radiated noise decreases by 1.4 dB.关键词：Gearbox;Modal participation factor;Vibration characteristic;Modal acoustic contribution
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发布时间：2022-11-10 - 摘要：Based on the topological structure theory of position and orientation characteristic （POC） set， a kind of series open chain mechanism composed of all rotating pairs is studied， and the POC set of vertical and parallel structures are compared. Methods using to analyze the structure are presented. Finally， the topological structure of 7R series mechanism is analyzed by using these methods.关键词：POC set;Dimension constraint type;7R serial mechanism;Topological structure
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发布时间：2022-11-10 - 摘要：To improve the light truck unidirectional self-increasing force brake of the brake performance， the finite element model of unidirectional self-increasing force brake is established， by using Abaqus software， the braking process simulation analysis of brake is carried out， a unidirectional self-increasing force brake of the axial and circumferential of the distribution of temperature field and gravitational field are got， and adopting the method of Manson-Coffin equation to predict the fatigue life of brake drum. The results show that during the whole braking process， the temperature and stress of the brake drum vary in zigzag shape， and the fatigue life of the brake drum is greatly affected by the temperature. In the process of braking， the change law of temperature field of brake drum is mainly affected by heat flux， convection heat transfer and heat conduction. The stress field of brake drum is mainly affected by the initial position and the contact between the inner surface of brake drum and the surface of friction sheet.关键词：Brake;Finite element;Thermal coupling analysis;Life prediction
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发布时间：2022-11-10 -
Analysis of Flash Temperature Characteristic of the Roller Enveloping End Face Engagement Worm Drive
摘要：In order to improve the scuffing load capacity and study the flash temperature of roller enveloping end face engagement worm drive， the mathematical model of friction coefficient between end face worm gear and roller gear under elastohydrodynamic lubrication is established based on tribology and meshing theory of roller enveloping end face engagement worm drive. The time-varying law of friction coefficient is analyzed in the meshing process. On this basis， the calculation model of flash temperature of roller enveloping end face worm drive under elastohydrodynamic lubrication is built based on tribology principle and Block flash temperature theory. The distribution of flash temperature of roller enveloping end face engagement worm drive is analyzed by using Matlab software from mesh in to mesh out. And the input power， lube oil viscosity， roller radius and orifice coefficient， which impacted the flash temperature of this transmission pair are analyzed. The numerical example shows that the input power and lube oil viscosity should not too bigger， roller radius and orifice coefficient should not too smaller，for effectively improving the scuffing strength of the roller enveloping end face engagement worm drive．The research result is very significant for the study of scuffing strength and thermal stress analysis of roller enveloping end face engagement worm drive.关键词：Roller enveloping;End face engagement worm gear;Friction coefficient;Flash temperature- 4
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发布时间：2022-11-10
Test·Analysis
- 摘要：In order to evaluate the fatigue durability of the hybrid vehicle driveline， the load simulation test system is used to simulate the dynamic load spectrum of the vehicle on the actual road. The dynamics analysis of the load simulation system is carried out to establish an integrated analysis model of the load simulation system. The dynamic load spectrum is collected in the test field， and analyzed and processed to determine the load spectrum bandwidth of the load simulation system. In order to improve the simulation accuracy of the dynamic load spectrum of the load simulation system， a dynamic load spectrum simulation method based on RPC （Remote Parameter Control） is proposed， which reduces the tracking error by simulation iterative control. After 15 simulation iterations， the speed and torque control accuracy （1.03%， 2.38%） are improved by 5.72% and 6.94% respectively compared with the conventional PID control （6.75%， 9.32%）. The dynamic load spectrum response after iteration， the error can be controlled within 5%， which can meet the indoor bench durability test requirements.关键词：Transmission system;Load simulation;Remote parameter control;Analog iterative control
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发布时间：2022-11-10 - 摘要：Aiming at a hypersonic wind tunnel angle of attack mechanism， its special structural characteristics and kinematics are analyzed， and its parameter identification and control methods are studied. Firstly， the attack angle mechanism is modeled with kinematics， and the nonlinear kinematics models of pitch and yaw degrees of freedom are discussed. Aiming at the characteristics of many error factors in the pitch and yaw degrees of freedom transmission chain， the laser tracker is used to detect and the parameters in the kinematic model are accurately fitted with the nonlinear least square method. The experimental results show that， the parameter identification results meet the precise positioning requirements of the mechanism， the positioning accuracy is better than the accuracy index of 1'. In view of the characteristics of the nonlinear transmission of the pitch and yaw mechanism and the need for accurate control of the mechanism speed in the wind tunnel test， on the basis of parameter identification， the virtual axis， electronic cam and electronic gear technology are used to achieve the speed of pitch and yaw degrees of freedom precise control， speed control accuracy is better than the accuracy index of 0.5 （°）/s.关键词：Attack angle mechanism;Parameter identification;Nonlinear least square;Electronic cam;Virtual axis
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发布时间：2022-11-10 -
Mechanism and Adjustment of the Deviation of Gearbox Output Phase of Co-rotating Twin Screw Extruder
摘要：The co-rotating twin screw extruder is widely used in the modification， granulating， premix and other production of engineering plastics. The co-rotating gearbox is one of the important components of the extruder， the output phase of which is a key parameter for the capacity of the extruder. The formation mechanism of deviation of gearbox output phase is analyzed， and the effective measure of assembly adjustment is proposed. Some reference for the research and design of similar transmission system is provided.关键词：Co-rotating gearbox;Output phase;Adjustment- 6
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发布时间：2022-11-10 - 摘要：The basic concepts and main characteristics of the oil whirl and oil whip are introduced， and the oil whip may cause serious damage to the unit， which must be paid great attention to and dealt with in time. Through the analysis of the frequency spectrogram， the orbit and the operating parameters of the fault unit， the relationship between them is pointed out. At last， the common measures to deal with the problem of oil whip are summarized， which provides a reference to deal with these problems.关键词：Oil whip;Sliding bearing;Frequency spectrum analysis
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发布时间：2022-11-10
Development·Application
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