Pneumatic brake valves used in vehicle trailers - A review

Abstract

The paper presents an overview of the basic air brake valves used in agricultural trailers and a conceptual solution proposed by the authors. In addition to a review of existing solutions, the history of air brake systems is presented and their basic subdivisions are described. The review focuses on the analysis of classic pneumatic signal controlled brake valves, detailing their design, operation and characteristics. With reference to current design trends, mainly based on a modified relay valve, the validity of a conceptual pneumatically controlled differential valve with mechatronic setpoint control was briefly discussed and analysed. The analysis of the design of current electro-pneumatic valve solutions has shown their pneumatic protection in the event of failure of the electronic system, which is a key argument for improving systems controlled by pneumatic signals to meet current regulatory requirements. An overview of the solutions and the scope of the authors' research interests will make it possible to present a conceptual differential valve with reduced response time, described briefly in the manuscript.