122 results about "Meshing stiffness" patented technology

The invention discloses a modeling method for transmitting mechanism torsional vibration analysis of a passenger car under different operating conditions. The modeling method is used in accurate prediction and analysis of transmitting mechanism torsional vibration characteristics of a passenger car under different operating conditions; according to the method, on the basis of a traditional concentrated parameter model, engine excitation, crank link mechanism moment of inertia, time-varying characteristics of gear meshing stiffness, clutch torsional shock absorber and the non-linear stiffness of the gear backlash are added to consideration; a simulation model suitable for analysis of transmitting mechanism dynamics characteristics of passenger car under different operating conditions is established; the engine cylinder pressure data under specific operating conditions is obtained through actual measurement or simulation as excitation; equivalent resistance moments of the rolling resistance and the air resistance are used as load to realize simulation of a passenger car under specific driving conditions. The method of the invention has strong practicality and has simple calculation; the method is suitable for the accurate prediction and analysis of transmitting mechanism torsional vibration characteristics of a passenger car.

The invention proposes a method considering axial deformation for calculating time-varying meshing stiffness of a helical gear. The method aims at improving the accuracy of calculating the meshing stiffness of the helical gear. The method comprises the implementation steps of calculating the end surface bending stiffness, end surface shearing stiffness, radial compression stiffness and end surfacetooth base stiffness of the helical gear; calculating contact stiffness; calculating the end surface meshing stiffness of a single tooth pair; deducing and calculating axial bending stiffness, axialshearing stiffness and axial tooth base stiffness; calculating the meshing stiffness of the single tooth pair; calculating the time-varying meshing stiffness. According to the method, the influence ofaxial meshing force on the time-varying meshing stiffness of the helical gear is considered, a calculation expression for the quantitative calculation of the axial bending stiffness, axial shearing stiffness and axial tooth base stiffness of the helical gear is deduced, the time-varying meshing stiffness of the helical gear is calculated by combining all the stiffness in the end surface direction, the calculation accuracy is improved, and the method can be used for the dynamic performance analysis and optimization design of the helical gear.

Disclosed herein is a multi-mesh gear system, such as an epicyclic gear system, in which (a) optimal performance is not load-specific and (b) the same profile modifications can be applied on both flanks of the common gear. This is accomplished through a novel combination of a constant system contact ratio and gearing having mesh stiffness variation reducing, or MSVR, modifications. An MSVR modification, such as Differential Crowning, will minimize the self-excited component of dynamic load for gear meshes across different operating loads, resulting in an optimized gearset. The specification of a substantially constant contact ratio for the multi-mesh gear system allows the same MSVR modification to be used on both tooth flanks of the common gear, reducing the cost and complexity of manufacture.

The invention relates to a straight gear meshing stiffness calculation method considering complex matrix and crack propagation, and the method comprises the steps: obtaining an overall flexibility matrix of a driving wheel and a driven wheel of a meshing gear based on a finite element theory, and determining an overall flexibility matrix of a possible contact point at each meshing position; Introducing a nonlinear Hertz contact theory, and calculating a contact flexibility matrix of possible contact points at each meshing position; And introducing the overall flexibility matrix, the contact flexibility matrix and the initial gap vector of the possible contact point into a deformation coordination equation, and calculating the meshing stiffness of the meshing position. According to the method, crack propagation paths obtained through fracture mechanics can be considered at the same time, and the influence of a complex matrix structure (including a web structure and a lightening hole structure) on the meshing rigidity of the straight gear can be considered at the same time. According to the method, the straight gear meshing stiffness considering the gear web structure, the lighteninghole structure and the crack propagation path can be calculated at the same time. The result of the method is verified by adopting a three-dimensional contact finite element method, and the result shows that the method disclosed by the invention has higher precision for calculating the meshing stiffness of the crack-containing complex matrix gear.

The invention discloses a method for calculating the time-varying meshing stiffness of an internal meshing gear pair of a straight-tooth cylindrical gear. The method comprises the following steps thatS1, single-tooth meshing stiffness of an inner gear and an outer gear in a straight-tooth cylindrical gear inner meshing gear pair is calculated on the basis of a potential energy method; S2, the single-tooth meshing stiffness of the inner gear and the outer gear is converted into a function about the angular displacement of the outer gear according to the geometrical relationship; And S3, whether the stage of gear pair meshing is single meshing or double meshing is judged through gear angular displacement, and the time-varying meshing stiffness value of the inner meshing gear pair of the straight-tooth cylindrical gear is calculated on the basis of the stiffness series-parallel theory. On one hand, the blank of a time-varying stiffness calculation method of the gear under internal meshing at the present stage can be made up, and on the other hand, solving can be simplified and the calculation efficiency can be improved by combining gear geometric information on the basis of giving play to the high-precision advantage of an analytical method.