Contour bevel gears have the advantages of high coincidence,low noise and large bearing capacity,which are widely used in automobile manufacturing,shipbuilding and construction machinery.However,when the surface quali...Contour bevel gears have the advantages of high coincidence,low noise and large bearing capacity,which are widely used in automobile manufacturing,shipbuilding and construction machinery.However,when the surface quality is poor,the effective contact area between the gear mating surfaces decreases,affecting the stability of the fit and thus the transmission accuracy,so it is of great significance to optimize the surface quality of the contour bevel gear.This paper firstly analyzes the formation process of machined surface roughness of contour bevel gears on the basis of generating machining method,and dry milling experiments of contour bevel gears are conducted to analyze the effects of cutting speed and feed rate on the machined surface roughness and surface topography of the workpiece.Then,the surface defects on the machined surface of the workpiece are studied by SEM,and the causes of the surface defects are analyzed by EDS.After that,XRD is used to compare the microscopic grains of the machined surface and the substrate material for diffraction peak analysis,and the effect of cutting parameters on the microhardness of the workpiece machined surface is investigated by work hardening experiment.The research results are of great significance for improving the machining accuracy of contour bevel gears,reducing friction losses and improving transmission efficiency.展开更多
This paper took Pro/ENGINEER wildfire2.0 as the development environment and realized the involute helical gears’three-dimensional model parameterized designing which made use of the parameter and relation function of...This paper took Pro/ENGINEER wildfire2.0 as the development environment and realized the involute helical gears’three-dimensional model parameterized designing which made use of the parameter and relation function of Pro/E.This paper also provided a method of editing the equation of the tooth curve,and it can ensure the high precision of the involute helical gear model.It developed the man-machine interactive parameterized designing interface making use of the secondary development function offered by Pro/TOOLKIT.The users can revise the involute helical gear easily by this man-machine interactive.It de- tailedly introduced the method of designing the man-machine interactive interface Using Pro/TOOLKIT and Visual C++.When the users input correlation parameters according to the prompt of the man-machine interactive interface,the three-dimensional model of the involute helical gear is auto-generated.This method simplified the product design process,shortened the period of de- veloping and improved the design efficiency of the gear greatly.展开更多
A dynamic analysis approcach to investigate the state of load distribution among contact bearings of double circular are belical gears is proposed and a computer program is developed for calculating the factor of iced...A dynamic analysis approcach to investigate the state of load distribution among contact bearings of double circular are belical gears is proposed and a computer program is developed for calculating the factor of iced distribution based on the theory of W-N gears. The changing situations of load distribution among contact bearings of the gears influenced by main issues are analyzed by a series of parametric studies.展开更多
Numerical simulations based on a conjugate heat transfer solver have been carried out to analyze various gas quenching configurations involving a helical gear streamed by an air flow at atmospheric pressure in a gas q...Numerical simulations based on a conjugate heat transfer solver have been carried out to analyze various gas quenching configurations involving a helical gear streamed by an air flow at atmospheric pressure in a gas quenching chamber. In order to optimize the heat transfer coefficient distribution at key positions on the specimen, configurations involving layers of gears and flow ducts comprising single to multiple gears have been simulated and compared to standard batch configurations in gas quenching. Measurements have been performed covering the local heat transfer for single gears and batch of gears. The homogeneity of the heat transfer coefficient is improved when setting up a minimal distance between the gears (batch density) and when introducing flow ducts increasing the blocking grade around the gears. An offset between layers of the batch as well as flow channels around the gears plays a significant role in increasing the intensity and the homogeneity of the heat transfer in gas quenching process.展开更多
The multistage face gears are the core component of the planetary gear train,which is symmetrically meshed by multiple single-stage face gear and multiple cylindrical gears.However,it is difficult to synchronize the c...The multistage face gears are the core component of the planetary gear train,which is symmetrically meshed by multiple single-stage face gear and multiple cylindrical gears.However,it is difficult to synchronize the contact between face gears and cylindrical gear due to the tooth number differences.Thus,the interference problems between two stages and big stress concentration are obvious.The crown surface configuration technology and structure design were introduced to optimize the meshing condition.To improve the double crown design feasibility and meshing stability,it is necessary to establish a reasonable multistage face gears pair simulation model to evaluate various influence factors on the contact condition and quasi-static characteristics of multistage face gears structure.The relevant scatter plots are fitted by comparing the contact results with different crown quantities and friction coefficients to intuitively obtain the variation regularity of maximum deformation,maximum strain,maximum stress and maximum strain energy.The natural frequency and mode coefficient are also determined by modal analysis under these two conditions.All the above mentioned studies verified the contact conjugate properties of double crown surface configuration were suitable.The results can provide a foundation for structure optimization and transmission reliability of multistage face gears.展开更多
After an introductiou of the Plucker coordinate geometry, a discussion is made of the expression of screws in Plucker coordiuates and the addition of screws’ As a result, the geometry or geuerating gears is re-studie...After an introductiou of the Plucker coordinate geometry, a discussion is made of the expression of screws in Plucker coordiuates and the addition of screws’ As a result, the geometry or geuerating gears is re-studied and a formula is derived for calculating the axode leugth or hypoid gears’展开更多
A successive tooth forming process for producing large modulus spur gears(m>2.5 mm)is firstly proposed in this paper to break the restrictions of large forming load and large equipment structure of traditional plas...A successive tooth forming process for producing large modulus spur gears(m>2.5 mm)is firstly proposed in this paper to break the restrictions of large forming load and large equipment structure of traditional plastic forming.It contains the preforming stage and the finishing stage.In the first stage,the die with a single-tooth preforms gear teeth one by one through several passes.In the second stage,the other die with multi-teeth refines the preformed teeth into required shape.The influence of total pressing depth and feed distribution in preforming stage on final forming quality is analyzed by numerical simulation,and the reasonable process parameters are presented.Successive tooth forming experiments are carried out on the self-designed gear forming device to verify the optimal simulation results.Gears without fold defects are well formed both in simulations and experiments,proving the feasibility of this method.Compared with the whole die forging process,the new technology has advantages of smaller load and simpler tooling,which shows a good potential for manufacturing large modulus and large size spur gears.展开更多
A quasi-static wear model for helical gears is proposed based on finite element method and Archard's formula to investigate the wear characteristics of tooth surface in real operation conditions. The numerical sim...A quasi-static wear model for helical gears is proposed based on finite element method and Archard's formula to investigate the wear characteristics of tooth surface in real operation conditions. The numerical simulation reveals that the wear depth distributes unevenly along the tooth lead and varies along the tooth profile. The surface wear depth claims its minimal value at the pitch circle and reaches its maximal value near the tooth root of the pinion. The effects of misalignment on wear depth are further investigated to provide useful information for gear designers. The numerical simulation reveals that the vertical misalignment is more influential than the parallel misalignment on the gear wear depth. Therefore, to eliminate the negative effects of misalignment, the misalignment should be strictly controlled.展开更多
To study the lubrication of the contact zone between half-shaft gears and planet gears in the power-split device (PSD), TEHL line contact of bevel gears in PSD is approximately computed based on a theory in which a be...To study the lubrication of the contact zone between half-shaft gears and planet gears in the power-split device (PSD), TEHL line contact of bevel gears in PSD is approximately computed based on a theory in which a bevel gear is equalized to an equivalent spur gear. In the calculation, the housing is taken as the reference system and the influence of the housing’s rotating on the lubrication is ignored. Film pressure, film thickness and temperature rise are analyzed under maximum load condition. This research provides some approximate reference data for the design of lubrication and cooling system of PSD.展开更多
An important concern in gear design is to reduce the dynamic load and noise of gear systems. It has been found that the noise generated from gearing is basically due to gearbox vibration excited by the dynamic load. S...An important concern in gear design is to reduce the dynamic load and noise of gear systems. It has been found that the noise generated from gearing is basically due to gearbox vibration excited by the dynamic load. Since one of the situations that demand high performance is the high rotational speeds, there is a need to understand the dynamic behavior of the gears at such speeds. Such knowledge would shed light on detrimental characteristics like dynamic loads and vibrations. An efficient way in performing studies on the dynamic behavior of gears is using computer aided analysis on numerical models. In this paper, a developed computer program is introduced to analyze dynamic behavior of spur gears with asymmetric teeth that have a potential use for higher performance in wind turbine gearboxes. This program can be used to compare conventional spur gears with symmetric teeth and spur gears with asymmetric teeth. By using this program, gear designers can design a gear pair and obtain results, e.g dynamic Load, transmitted torque, static transmission error, and frequency spectra of static transmission error etc., just by pressing a command button.展开更多
With 29 million vehicles manufactured just last year, anda 3.2-percent year on yeargrowth, China remains the world's largest car manufacturer. For thepast five years, Chinese auto makers havebeen picking up speed. Lo...With 29 million vehicles manufactured just last year, anda 3.2-percent year on yeargrowth, China remains the world's largest car manufacturer. For thepast five years, Chinese auto makers havebeen picking up speed. Local brands nowaccount for 60 percent of all sales of sports utility vehicles in the country.展开更多
For high-speed heavy-duty gears in operation is prone to high tooth surface temperature rise and thus produce tooth surface gluing leading to transmission failure and other adverse effects,but in the gear optimization...For high-speed heavy-duty gears in operation is prone to high tooth surface temperature rise and thus produce tooth surface gluing leading to transmission failure and other adverse effects,but in the gear optimization design and little consideration of thermal transmission errors and thermal resonance and other factors,while the conventional multi-objective optimization design methods are difficult to achieve the optimum of each objective.Based on this,the paper proposes a gear multi-objective reliability optimisation design method based on the APCK-SORA model.The PC-Kriging model and the adaptive k-means clustering method are combined to construct an adaptive reliability analysis method(APCK for short),which is then integrated with the SORA optimisation algorithm.The objective function is the lightweight of gear pair,the maximum overlap degree and the maximum anti-glue strength;the basic parameters of the gear and the sensitivity parameters affecting the thermal deformation and thermal resonance of the gear are used as design variables;the amount of thermal deformation and thermal resonance,as well as the contact strength of the tooth face and the bending strength of the tooth root are used as constraints;the optimisation results show that:the mass of the gear is reduced by 0.13kg,the degree of overlap is increased by 0.016 and the coefficient of safety against galling Compared with other methods,the proposed method is more efficient than the other methods in meeting the multi-objective reliability design requirements of lightweighting,ensuring smoothness and anti-galling capability of high-speed heavy-duty gears.展开更多
A novel weft insertion mechanism named eccentric conjugate non-circular gear & crank-rocker & gears train weft insertion mechanism was proposed in order to better meet the requirements of rapier loom's wef...A novel weft insertion mechanism named eccentric conjugate non-circular gear & crank-rocker & gears train weft insertion mechanism was proposed in order to better meet the requirements of rapier loom's weft insertion mechanism as well as reduce the manufacturing difficulty. Meanwhile, based on the working principle of this mechanism, kinematical mathematic models of this mechanism were established and an aided analysis and simulation software was compiled. The influences of eccentricity ratio, deformation coefficient, and other important parameters on the kinematics characteristics of this mechanism were analyzed by using the software. A group of preferable parameters which could meet the requirements of weft insertion technology were obtained by means of human-computer interactive optimization method. The maximum velocity, maximum acceleration, and variation of acceleration of this mechanism are smaller than those of the conjugate cam weft insertion mechanism applied on TT96 rapier loom under the conditions of the same unilateral total stroke of rapier head and the same rotary speed of loom spindle; meanwhile the other demands of weaving technology can be met by this novel weft insertion mechanism.展开更多
It is known that manufacture of hypoid gears is difficult and complicated, the reason lies on the limitation of traditional mechanical machine tools. With the development of NC machine tools, there should be new ways ...It is known that manufacture of hypoid gears is difficult and complicated, the reason lies on the limitation of traditional mechanical machine tools. With the development of NC machine tools, there should be new ways of cutting this kind of gear. Therefore, an idea to generate gears with conjugating tooth surfaces is proposed, based on the 'flexibility' characteristic of NC that means various motions, in a sense, can be performed arbitrarily on NC machine tools. Using this method, the direction of the contact path on tooth surfaces can be controlled, and also, theoretically, the generated tooth surfaces can transmit motion at specific transmission ratio curve.展开更多
The involute bevoloid gears has been more and more widely used in Practical industry, but the researchahout its interference has never been reported. In order to satisfy the design need of intemal involute bevoloid ge...The involute bevoloid gears has been more and more widely used in Practical industry, but the researchahout its interference has never been reported. In order to satisfy the design need of intemal involute bevoloid geare,two importan interference conditions are discussed in deail and verification formulae are given as appropriate. There-fore, this paper has an instructive meaning to the design of intemal boloid geare.展开更多
In mechanical gear systems, dust, noise, vibration, and tooth wear are generated by frictions among gear teeth, and suppressing friction requires lubrication. Magnetic gears transmit torque by magnetic forces without ...In mechanical gear systems, dust, noise, vibration, and tooth wear are generated by frictions among gear teeth, and suppressing friction requires lubrication. Magnetic gears transmit torque by magnetic forces without contact and so avoid contact-related problems. The present paper discusses magnet arrangements and the shape of stationary gear teeth to improve transmission torque in surface magnet type magnetic gear transmission mechanisms.展开更多
Lubrication failure is one of the main failure forms of gear failure.Time varying meshing stiffness is an important factor affecting the dynamic behavior of gears.However,the influence of oil film stiffness is usually...Lubrication failure is one of the main failure forms of gear failure.Time varying meshing stiffness is an important factor affecting the dynamic behavior of gears.However,the influence of oil film stiffness is usually ignored in the research process.In this paper,according to the meshing characteristics of double involute gears,based on the non-Newtonian thermal EHL theory,a new calculation method of normal and tangential oil film stiffness for double involute gears is established by the idea of subsection method.The oil film stiffness difference between double involute gears and common involute gears is analyzed,and the influence of tooth waist order parameters,working conditions,and thermal effect on the oil film stiffness are studied.The results reveal that there are some differences between normal and tangential oil film stiffness between double involute gears and common involute gears,but there is little difference.Compared with the torque,rotation speed and initial viscosity of the lubricating oil,the tooth waist order parameters have less influence on the oil film stiffness.Thermal effect has a certain influence on normal and tangential oil film stiffness,which indicates that the influence of thermal effect on the oil film can not be ignored.This research proposes a calculation method of normal and tangential oil film stiffness suitable for double involute gears,which provides a theoretical basis for improving the stability of the transmission.展开更多
基金National Key R&D Program of China(Grant No.2019YFE0121300)Yancheng Hali Power Transmission and Intelligent Equipment Industrial Research Institute Project。
文摘Contour bevel gears have the advantages of high coincidence,low noise and large bearing capacity,which are widely used in automobile manufacturing,shipbuilding and construction machinery.However,when the surface quality is poor,the effective contact area between the gear mating surfaces decreases,affecting the stability of the fit and thus the transmission accuracy,so it is of great significance to optimize the surface quality of the contour bevel gear.This paper firstly analyzes the formation process of machined surface roughness of contour bevel gears on the basis of generating machining method,and dry milling experiments of contour bevel gears are conducted to analyze the effects of cutting speed and feed rate on the machined surface roughness and surface topography of the workpiece.Then,the surface defects on the machined surface of the workpiece are studied by SEM,and the causes of the surface defects are analyzed by EDS.After that,XRD is used to compare the microscopic grains of the machined surface and the substrate material for diffraction peak analysis,and the effect of cutting parameters on the microhardness of the workpiece machined surface is investigated by work hardening experiment.The research results are of great significance for improving the machining accuracy of contour bevel gears,reducing friction losses and improving transmission efficiency.
文摘This paper took Pro/ENGINEER wildfire2.0 as the development environment and realized the involute helical gears’three-dimensional model parameterized designing which made use of the parameter and relation function of Pro/E.This paper also provided a method of editing the equation of the tooth curve,and it can ensure the high precision of the involute helical gear model.It developed the man-machine interactive parameterized designing interface making use of the secondary development function offered by Pro/TOOLKIT.The users can revise the involute helical gear easily by this man-machine interactive.It de- tailedly introduced the method of designing the man-machine interactive interface Using Pro/TOOLKIT and Visual C++.When the users input correlation parameters according to the prompt of the man-machine interactive interface,the three-dimensional model of the involute helical gear is auto-generated.This method simplified the product design process,shortened the period of de- veloping and improved the design efficiency of the gear greatly.
文摘A dynamic analysis approcach to investigate the state of load distribution among contact bearings of double circular are belical gears is proposed and a computer program is developed for calculating the factor of iced distribution based on the theory of W-N gears. The changing situations of load distribution among contact bearings of the gears influenced by main issues are analyzed by a series of parametric studies.
文摘Numerical simulations based on a conjugate heat transfer solver have been carried out to analyze various gas quenching configurations involving a helical gear streamed by an air flow at atmospheric pressure in a gas quenching chamber. In order to optimize the heat transfer coefficient distribution at key positions on the specimen, configurations involving layers of gears and flow ducts comprising single to multiple gears have been simulated and compared to standard batch configurations in gas quenching. Measurements have been performed covering the local heat transfer for single gears and batch of gears. The homogeneity of the heat transfer coefficient is improved when setting up a minimal distance between the gears (batch density) and when introducing flow ducts increasing the blocking grade around the gears. An offset between layers of the batch as well as flow channels around the gears plays a significant role in increasing the intensity and the homogeneity of the heat transfer in gas quenching process.
基金This work was supported by the National Natural Science Foundation of China(grant number 51575191).
文摘The multistage face gears are the core component of the planetary gear train,which is symmetrically meshed by multiple single-stage face gear and multiple cylindrical gears.However,it is difficult to synchronize the contact between face gears and cylindrical gear due to the tooth number differences.Thus,the interference problems between two stages and big stress concentration are obvious.The crown surface configuration technology and structure design were introduced to optimize the meshing condition.To improve the double crown design feasibility and meshing stability,it is necessary to establish a reasonable multistage face gears pair simulation model to evaluate various influence factors on the contact condition and quasi-static characteristics of multistage face gears structure.The relevant scatter plots are fitted by comparing the contact results with different crown quantities and friction coefficients to intuitively obtain the variation regularity of maximum deformation,maximum strain,maximum stress and maximum strain energy.The natural frequency and mode coefficient are also determined by modal analysis under these two conditions.All the above mentioned studies verified the contact conjugate properties of double crown surface configuration were suitable.The results can provide a foundation for structure optimization and transmission reliability of multistage face gears.
文摘After an introductiou of the Plucker coordinate geometry, a discussion is made of the expression of screws in Plucker coordiuates and the addition of screws’ As a result, the geometry or geuerating gears is re-studied and a formula is derived for calculating the axode leugth or hypoid gears’
基金Supported by National Natural Science Foundation of China(Grant No.51475271).
文摘A successive tooth forming process for producing large modulus spur gears(m>2.5 mm)is firstly proposed in this paper to break the restrictions of large forming load and large equipment structure of traditional plastic forming.It contains the preforming stage and the finishing stage.In the first stage,the die with a single-tooth preforms gear teeth one by one through several passes.In the second stage,the other die with multi-teeth refines the preformed teeth into required shape.The influence of total pressing depth and feed distribution in preforming stage on final forming quality is analyzed by numerical simulation,and the reasonable process parameters are presented.Successive tooth forming experiments are carried out on the self-designed gear forming device to verify the optimal simulation results.Gears without fold defects are well formed both in simulations and experiments,proving the feasibility of this method.Compared with the whole die forging process,the new technology has advantages of smaller load and simpler tooling,which shows a good potential for manufacturing large modulus and large size spur gears.
基金Funded by National Natural Science Foundation of China(Nos.51375013,50905122,and 51405003)Anhui Provincial Natural Science Foundation(No.1208085ME64)
文摘A quasi-static wear model for helical gears is proposed based on finite element method and Archard's formula to investigate the wear characteristics of tooth surface in real operation conditions. The numerical simulation reveals that the wear depth distributes unevenly along the tooth lead and varies along the tooth profile. The surface wear depth claims its minimal value at the pitch circle and reaches its maximal value near the tooth root of the pinion. The effects of misalignment on wear depth are further investigated to provide useful information for gear designers. The numerical simulation reveals that the vertical misalignment is more influential than the parallel misalignment on the gear wear depth. Therefore, to eliminate the negative effects of misalignment, the misalignment should be strictly controlled.
文摘To study the lubrication of the contact zone between half-shaft gears and planet gears in the power-split device (PSD), TEHL line contact of bevel gears in PSD is approximately computed based on a theory in which a bevel gear is equalized to an equivalent spur gear. In the calculation, the housing is taken as the reference system and the influence of the housing’s rotating on the lubrication is ignored. Film pressure, film thickness and temperature rise are analyzed under maximum load condition. This research provides some approximate reference data for the design of lubrication and cooling system of PSD.
文摘An important concern in gear design is to reduce the dynamic load and noise of gear systems. It has been found that the noise generated from gearing is basically due to gearbox vibration excited by the dynamic load. Since one of the situations that demand high performance is the high rotational speeds, there is a need to understand the dynamic behavior of the gears at such speeds. Such knowledge would shed light on detrimental characteristics like dynamic loads and vibrations. An efficient way in performing studies on the dynamic behavior of gears is using computer aided analysis on numerical models. In this paper, a developed computer program is introduced to analyze dynamic behavior of spur gears with asymmetric teeth that have a potential use for higher performance in wind turbine gearboxes. This program can be used to compare conventional spur gears with symmetric teeth and spur gears with asymmetric teeth. By using this program, gear designers can design a gear pair and obtain results, e.g dynamic Load, transmitted torque, static transmission error, and frequency spectra of static transmission error etc., just by pressing a command button.
文摘With 29 million vehicles manufactured just last year, anda 3.2-percent year on yeargrowth, China remains the world's largest car manufacturer. For thepast five years, Chinese auto makers havebeen picking up speed. Local brands nowaccount for 60 percent of all sales of sports utility vehicles in the country.
基金financed with the means of Yingkou Institute of Technology Introduction of doctors to start the fund project (YJRC202109).
文摘For high-speed heavy-duty gears in operation is prone to high tooth surface temperature rise and thus produce tooth surface gluing leading to transmission failure and other adverse effects,but in the gear optimization design and little consideration of thermal transmission errors and thermal resonance and other factors,while the conventional multi-objective optimization design methods are difficult to achieve the optimum of each objective.Based on this,the paper proposes a gear multi-objective reliability optimisation design method based on the APCK-SORA model.The PC-Kriging model and the adaptive k-means clustering method are combined to construct an adaptive reliability analysis method(APCK for short),which is then integrated with the SORA optimisation algorithm.The objective function is the lightweight of gear pair,the maximum overlap degree and the maximum anti-glue strength;the basic parameters of the gear and the sensitivity parameters affecting the thermal deformation and thermal resonance of the gear are used as design variables;the amount of thermal deformation and thermal resonance,as well as the contact strength of the tooth face and the bending strength of the tooth root are used as constraints;the optimisation results show that:the mass of the gear is reduced by 0.13kg,the degree of overlap is increased by 0.016 and the coefficient of safety against galling Compared with other methods,the proposed method is more efficient than the other methods in meeting the multi-objective reliability design requirements of lightweighting,ensuring smoothness and anti-galling capability of high-speed heavy-duty gears.
基金National Natural Science Foundation of China(No.50875243)
文摘A novel weft insertion mechanism named eccentric conjugate non-circular gear & crank-rocker & gears train weft insertion mechanism was proposed in order to better meet the requirements of rapier loom's weft insertion mechanism as well as reduce the manufacturing difficulty. Meanwhile, based on the working principle of this mechanism, kinematical mathematic models of this mechanism were established and an aided analysis and simulation software was compiled. The influences of eccentricity ratio, deformation coefficient, and other important parameters on the kinematics characteristics of this mechanism were analyzed by using the software. A group of preferable parameters which could meet the requirements of weft insertion technology were obtained by means of human-computer interactive optimization method. The maximum velocity, maximum acceleration, and variation of acceleration of this mechanism are smaller than those of the conjugate cam weft insertion mechanism applied on TT96 rapier loom under the conditions of the same unilateral total stroke of rapier head and the same rotary speed of loom spindle; meanwhile the other demands of weaving technology can be met by this novel weft insertion mechanism.
基金This project is supported by National Natural Science Foundation of China (No. 59775087).
文摘It is known that manufacture of hypoid gears is difficult and complicated, the reason lies on the limitation of traditional mechanical machine tools. With the development of NC machine tools, there should be new ways of cutting this kind of gear. Therefore, an idea to generate gears with conjugating tooth surfaces is proposed, based on the 'flexibility' characteristic of NC that means various motions, in a sense, can be performed arbitrarily on NC machine tools. Using this method, the direction of the contact path on tooth surfaces can be controlled, and also, theoretically, the generated tooth surfaces can transmit motion at specific transmission ratio curve.
文摘The involute bevoloid gears has been more and more widely used in Practical industry, but the researchahout its interference has never been reported. In order to satisfy the design need of intemal involute bevoloid geare,two importan interference conditions are discussed in deail and verification formulae are given as appropriate. There-fore, this paper has an instructive meaning to the design of intemal boloid geare.
文摘In mechanical gear systems, dust, noise, vibration, and tooth wear are generated by frictions among gear teeth, and suppressing friction requires lubrication. Magnetic gears transmit torque by magnetic forces without contact and so avoid contact-related problems. The present paper discusses magnet arrangements and the shape of stationary gear teeth to improve transmission torque in surface magnet type magnetic gear transmission mechanisms.
基金Supported by National Natural Science Foundation of China(Grant No.52075279)。
文摘Lubrication failure is one of the main failure forms of gear failure.Time varying meshing stiffness is an important factor affecting the dynamic behavior of gears.However,the influence of oil film stiffness is usually ignored in the research process.In this paper,according to the meshing characteristics of double involute gears,based on the non-Newtonian thermal EHL theory,a new calculation method of normal and tangential oil film stiffness for double involute gears is established by the idea of subsection method.The oil film stiffness difference between double involute gears and common involute gears is analyzed,and the influence of tooth waist order parameters,working conditions,and thermal effect on the oil film stiffness are studied.The results reveal that there are some differences between normal and tangential oil film stiffness between double involute gears and common involute gears,but there is little difference.Compared with the torque,rotation speed and initial viscosity of the lubricating oil,the tooth waist order parameters have less influence on the oil film stiffness.Thermal effect has a certain influence on normal and tangential oil film stiffness,which indicates that the influence of thermal effect on the oil film can not be ignored.This research proposes a calculation method of normal and tangential oil film stiffness suitable for double involute gears,which provides a theoretical basis for improving the stability of the transmission.