Vehicle including compressed air consuming devices and a method of operating the same

Abstract

A vehicle, such as a lorry or a bus, includes compressed air consuming devices and a power driven compressor to deliver compressed air to at least one storage tank. A control device controls the operation of the compressor so as to maintain the air pressure in the tank at a desired pressure level sufficient to operate the air consuming devices, such as a braking system and a suspension system, when needed. The air pressure is usually maintained substantially at a predetermined first elevated level or value. However, based on signals from position identification means, such as a global navigation system or other external or internal position identification sources the control device controls the operation of the compressor so as to change the pressure of the air in the storage tank to a predetermined second elevated level or value substantially different from the first level or value in response to receiving from the position identification means an indication to the effect that the vehicle is approaching or has arrived at one of a plurality of predetermined positions and / or positions fulfilling predetermined criteria.

Description

BACKGROUND AND SUMMARY[0001]The present invention relates to a method of operating compressed air systems in vehicles, such as lorries with or without trailers, buses and other heavy vehicles, which include compressed air consuming devices, such as pneumatic braking and suspension systems.[0002]Compressed air systems for such vehicles conventionally comprise a power driven compressor to deliver compressed air to one or more storage tanks from which the air consuming devices are fed. The operation of the compressor is usually controlled by a pressure regulator system maintaining an air pressure within the storage tanks at a rather high level, such as about 10-12 bars, which is considered to be sufficient to meet the need of operating the air consuming devices even in the most demanding situations, such as frequent braking or braking over a prolonged period of time.[0003]The constant use of such high pressure in the storage tank(s) involves several disadvantages. As the compressor's e...

AI Technical Summary

Benefits of technology

[0010]The position identification means may be of any suitable kind being able to indicate when the vehicle is approaching or has arrived at one of a plurality of predetermined positions and / or positions where substantially higher or lower consumption of compressed air may be expected. The indication received from the position indication means may, for example, be based on map data and other information about road topology, drive pattern recognition, traffic information from external sources, sensors located on the vehicle and / or special signals generated by external sources. The information may be received by and processed in an electronic processing system, and based on predetermined criteria this processing system may determine when the air pressure level of the storage tank has to be changed.

Problems solved by technology

As the compressor's efficiency is lower at higher pressure the energy (fuel) consumption for producing pressurised air will increase.

This means that the pressure of the storage tank may be increased to a higher level at a certain location when the vehicle is fully loaded, but this increase may be cancelled if the vehicle is empty.

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