Study On Bidirectional-driven Overload Chain Drive Configuration Meshing Characteristic And Tooth Profile

Chain transmission has been widely used in most areas of the national economy, and thescope of its application is also expanding gradually. With the development of the technology,more and more individual demand put forward higher requirements to the performance of thechain transmission. Therefore, improve the performance of the chain transmission movementis a unstoppable tendency. The sprocket is the most important part of the chain transmissionmechanism, it largely determines the working conditions and the efficiency of the chaintransmission system. This dissertation studies in the bidirectional transmission chaintransmission system under the constraint of track,analyzes its orbital motion and powercharacteristics, explores the compensation methods of the polygon effect, while referring tothe successful experience of the gear tooth profile, derives new sprocket profile equation, andoptimizes the design by using ANSYS finite element analysis, enhances the stability andtransmission reliability of the chain transmission, provides a theoretical basis for the futuredesign of the chain transmission mechanism.Firstly, This dissertation analyzes the structural characteristics and principles of thebidirectional heavy-duty chain transmission, studies the polygon effect, and the chaintransmission planar structure is equivalent to a five-bar mechanism for a detailed explanationof the changes in the transport direction of the speed, deduces the formula of the speedchanges, obtains the factors of the velocity variations. Due to the complexity of the chaintransmission and the accuracy of traditional mathematical models cannot be guaranteed, soestablishes equivalent physical model, analyzes the chain transmission performance in bitten,gets the stress of the axis in the process of meshing with the sprocket off, provides reliablevalues for strength verification. Then establishes the chain transmission mechanismequivalent model-U-type trajectory constraints under the constraint in the limited space,analysis its structure and orbital parameters, analysis the position of the pin engages velocity,explores compensation polygon effects.Secondly, in order to improve the transmission characteristics, according to theparticularity of the trajectory, combining the chain transmission engaged feature theoretically,refer to the conjugate tooth profile method of the gear, to make the pin pure rolling on thesprocket root circle as the prerequisite, deduces the sprocket epicycloids equation, accordingto the property of the equidistant curve, gets the new sprocket tooth profile equation;refereeing to the sprocket design of the German standard, sets up the3D parametric model ofthe new sprocket wheel by using Pro/E.Finally, the modal analysis was carried out on the sprocket and the engagementmechanism by ANSYS. Gets the system’s inherent properties, including innate frequency andvibration mode. In order to avoid the resonance, makes the external exciting force frequency and the system natural frequency stagger. Then the stress of the sprocket wheel and theEngagement contact stress was analyzed, the data of theoretical calculation were comparedwith the results of the simulation analysis. At last, finds out the insecurity factors of the design,optimizes the design parameters of the chain wheel, gets the best solution, ensures the safetyand reliability of the structure, provides a certain reference for the design of the chaintransmission.