| Based on research findings about important phase of National Natural Science foundation of China(50275062) that has been finished, and in the support of the project of National Natural Science foundation of China– the meshing mechanism and the design method of neotype Hy-Vo chain(50575089), this paper analyses silent chain meshing with outside flanks and meshing mechanism and dynamics characteristics of neotype silent chain meshing with inside and outside flanks and involutes sprocket, and establishes meshing mechanism model as well as approach shock model during meshing; otherwise, according to analyzing the influence of silent chain on the force and performance of chain, it put forward design methods of guide board of different silent chain. Through the study on bench test, it validates the influence of guide board of silent chain on chain.An ideal math model of tooth profile of involute chain wheel is established, which is based on gear meshing principle and the relationship between involute and chain wheel. The establishment of this model provides an effective tool to analyze neotype silent chain and mechanics as well as dynamics characteristics of involute chain wheel meshing drive.Based on analyzing silent chain meshing with outside flanks and the meshing principle of chain wheel, without regard for the gap between link joint hole of silent chain and pin roll, a meshing model between silent chain meshing with outside flanks and involute chain wheel is established through coordinate conversion. This paper gives the equation of solving the position of initial meshing point and the equation of the position of location meshing point. After the real parameters of silent chain and chain wheel are input into the model and calculated, without considering the assembly gap, the approach course of the external mesh silent chain and involute curve sprocket-wheel is allocated instantly on the mathematical theory.In the paper, the tooth meshing principle of the new type internal and external compound geared silent chain and sprocket-wheel is analyzed, on the base of the meshing model of external silent chain and involute curve sprocket-wheel, The location and the initial approach moment of the new type internal and external geared silent chain and sprocket-wheel, and when the initial mesh changes to the external mesh, the alternating point location and alternating moment are studied. Further more their mathematical solving model is also given in the paper. Meantime after the actual parameters of the chain and sprocket is put into model and calculated, the important conclusion, that the tangent point location of the former chain internal arc and involute curve sprocket-wheel is lower than that of the later plate external straight flange, is gotten.In the paper, on the base of the meshing model of the external meshing silent chain and involute curve sprocket-wheel and the meshing model of the internal and external compound geared silent chain and sprocket-wheel found in front, by analyzing the dynamics character of tooth chain and involute curve sprocket-wheel, the approach shock model of the external meshing silent chain and involute curve sprocket-wheel and the approach shock model and the alternating shock model of the internal and external compound geared silent chain and sprocket-wheel are respectively found. By analyzing the approach shock model of the internal and external compound geared silent chain and sprocket-wheel, it is found that the approach shocking doesn't appear in theory, when the line linking silent chain internal arc center and the initial meshing point is the normal line of the sprocket-wheel meshing point. Further more, by analyzing the alternating shock model, it is found that the tangent point location of the former chain internal arc and involute curve sprocket-wheel and that of the later plate external straight flange is in the same location with no impact. These provide the theoretical foundation for designing high-performance chain in the future.The effect the tooth chain guide plate having on the stress and property is studied and the method designing the guide plate. To meet the assembly requirement, there is a assembly gap between chain plate hole and pin roll. The gap lead that in the process of chains beginning to be stressed for a row of chain having guide plate only guide plate is stressed , which easily lead to failure. In order to make the chain plate be entirely stressed under work load. The shape and size of guide plate should be designed rationally, which the extension compensation rate of chain plate comes up to the assembly gap in the case of the chain stressing smaller force. The advantage and disadvantage of the normal guide plate and the butterfly-shaped guide plate are analyzed, and further their design method are given in the paper. Besides when the guide plate bearing a certain force, its force and deformation is analyzed with the finite-element software—ansys. Then, for the butterfly-shaped guide, without affecting the strength of guide plate, the longer the butterfly-shaped plate waist top arc radius RG is ,the better the butterfly-shaped plate is. The size of waist median is H G>1/2 H . The arc height of guide plate bottom is increased as possible, and the top arc lower-most point had better not be lower that the linking center line of guide plate holes. in addition, by testing CL04-5,C3-11, C3T-9 and 10×11 film Hy-Vo that its pitch is 9.525, it is proved that the essentiality and feasibility of the viewpoint which by rationally designing guide plate the assemble gap of chain plate hole and pin roll put forward in the paper can be effectively compensated in the course of chain being stressed. Further more the experiment proves the rationality of the design method of the silent chain guide plate, which provides an important gist for designing guide plates. |
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