New construction of cycloidal gear unit made of plastics

Abstract

Cycloidal gears constitute the main working unit of the fluid power gerotor machine. The paper presents a way of increasing the load-carrying capacity of cycloidal unit made of plastic. The aim has been reached through design and material modifications. As a result of those modifications, a design concept of the cycloidal gear system, which is different from the structures previously produced, has been created. The introduced modifications are based on the theoretical analysis of stress and deformations that occur in cycloidal gears during their operation. The analysis was conducted by means of the finite element method. Although the main focus was on analyzing the mechanism behind the deformations, an attempt was also made at extending the application scope for finite element method. The analysis by means of finite element method has been conducted for plastic and steel at the same time. This is result of showed design in which plastics and steel form the construction together one integral part. As a result of the analysis, the maximum value of the working pressure at which hydraulic gerotor machines with plastic cycloidal gears can work was determined. Thanks to the use of the finite element method one can point out the way of introduction of plastics in hydraulic machines construction.

Keywords

Strength analysis plastics gear design finite element analysis conceptual design

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