Abstract

Background: Hydraulic transformers have become a key topic in the field of hydraulics in recent years. Recent studies have found that use of hydraulic transformers can expedite the development of integrated solutions for the global industry. The variable hydraulic transformer can simultaneously meet requirements for variations of both load flow and load pressure.

Objective: The purpose of this study was to provide an overview of patents concerning hydraulic transformers and to analyze the pressure characteristics of a variable hydraulic transformer, including the pressure ratio, instantaneous torque, average torque, and torque pulsation.

Results: We define the concepts of driving torque and drag torque. The concepts of relative and absolute torque pulsation are used to explain the role of the swash plate. Considering these factors, models of pressure characteristics are developed. The reason that the swash plate can adjust the load flow is argued. Torque pulsation and jump points of instantaneous pressure cause lower operational stability: controlled movement of the swash plate is a method of improving stability. The stability of the variable hydraulic transformer depends on the control angles of the port plate and swash plate and the pressures at the ports.

Conclusions: Use of a variable hydraulic transformer can solve flow control difficulties. To further enhance use of this concept, its noise, control, and structure require additional research.

Keywords: Complex refractive index, glass material, imaginary part, optical constants, real part, spectrophotometer.