Application of gear hydraulic machines in the composition of hydrostatic transmissions

Abstract

Abstract Hydraulic machines serve either to impart energy to the fluid flowing through them, or to obtain energy from the fluid for its further useful use. The number of hydraulic machines used in the national economy is increasing annually, due to the fact that, in comparison with electric motors, they have smaller overall dimensions and weight, and also have a higher ratio of torque on the output shaft to the moment of inertia of the rotor. In agriculture, hydraulic machines are widely used in crop production. Through the use of hydraulics and automation, the development of complex mechanization of production processes is carried out, which provides for the development of machines of increased power and reliability. Also, the use of hydraulic machines allows you to relieve the structure of rigid mechanical connections and allows a wide range of adjustment of the unit operation. The most widely used today are two types of hydraulic machines - piston and gear. The use of hydraulic piston machines places high demands on the degree of purification and quality of transmission oil, as well as on the qualifications of technical personnel to ensure quality maintenance. Gear hydraulic machines are less demanding on the purity of the working fluid, as well as simplicity in design, are quite reliable, have a low cost price and a wide range of rotational speeds, in addition, they are able to create a relatively high pressure with low weight. The overall efficiency of gear hydraulic machines, which is 90%, is slightly inferior to that of piston hydraulic machines, which reaches 93%, respectively. The given characteristics of gear hydraulic machines allow us to consider them, taking into account modern design features, as a power basis for a hydrostatic transmission, with a limitation in power of application.