Pascal non-circular-Pascal non-circular-non-circular three-wheel synchronous belt drive design method

Abstract

The invention discloses a Pascal non-circular-Pascal non-circular-non-circular three-wheel synchronous belt drive design method. The method comprises the steps that pitch curve equations of synchronous belt driving and driven wheels are established, and the driving and driven wheel drive ratio is computed according to the tangency polar coordinate theoretical computation theory; the circumference of a synchronous belt is computed, and all parameters of a pitch curve of a non-circular tensioning belt wheel are obtained through an iterative algorithm according to changes of the amount of relaxation of the circumference of the synchronous belt. According to the method, a tensioning wheel is a non-circular synchronous belt wheel with a free pitch curve and can compensate for the variation of relaxation of the synchronous belt in real time in the driving process and overcome the defect that traditional two-wheel non-circular belt drive cannot meet non-uniform velocity drive and real-time tensioning simultaneously. The circle diameter, the expansion length, the variation coefficient and the order of a Pascal non-circular pitch curve are adjustable. The shape of the Pascal non-circular pitch curve is adjusted through the four parameters. The drive ratio of a wider range can be realized. More specific non-uniform velocity drive requirements can be met.

Description

technical field [0001] The invention relates to a design method of non-circular synchronous belt transmission, in particular to a design method of Pascal non-circular-Pascal non-circular-non-circular three-wheel synchronous belt transmission with variable slack self-compensation. Background technique [0002] The transmission mechanism changes the motion form and speed of the input and output components to meet the requirements of different working environments. Among them, the non-uniform transmission mechanism occupies a very important position, and the common ones are the connecting rod mechanism, the cam mechanism, and the non-circular gear mechanism. Compared with the connecting rod mechanism and the cam mechanism, the non-circular gear mechanism has the advantages of compact structure, stable transmission, large transmission power, and easy dynamic balance. Therefore, it has been successfully used in processing machine tools, automatic machinery, transportation, instrum...

AI Technical Summary

Problems solved by technology

However, non-circular gear transmission is only suitable for non-uniform speed transmission occasions with small center distance and convenient lubrication, so non-circular flexible member (belt / chain) transmission suitable for large center distance, inconvenient lubrication and low manufacturing cost should be used born

Among them, the polygonal effect of non-circular chain transmission is obvious, so it is limited when there are strict requirements on the change law of non-uniform transmission ratio; at the same time, ordinary friction belt transmission cannot guarantee accurate transmission ratio law due to elastic sliding.

[0003] The current non-circular belt (chain) transmission has only 2 non-circular belt (chain) wheels - the driving wheel and the driven wheel. During the transmission process, because the pitch curve is non-circular, the slack of the belt (chain) is real-time. Therefore, it is impossible to guarantee the non-uniform transmission ratio change law and the real-time tension of the belt (chain) required by the work at the same time.

In practical application, in order to compensate the slack change of the belt (chain) in the transmission, the tension is realized by adding a spring, because the tension force changes in a movement cycle, and the tension force increases with the aggravation of the non-uniform velocity characteristic. The greater the range of change, this will in turn affect the accuracy of non-uniform speed transmission, and the dynamic characteristics will become worse; therefore, in actual engineering, non-circular belt (chain) transmission is rarely used in precise load high-speed transmission occasions

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