Publication Date: 2004-Jul-08
The IP.com Prior Art Database
A method for controlling a compressor (5) for a compressed air system in a vehicle (2), comprising the steps of: selecting a destination/s to which the vehicle is to be driven and brought to a standstill and where a compressed air consuming activity is intended to be activated, calculating a distance to the destination and/or a time to arrival at the destination, measuring a pressure in the compressed-air system, determining if the pressure is below a predetermined pressure adapted for the compressed-air consuming activity, determining if the vehicle is within a predetermined distance from the destination and/or estimated to arrive at the destination within a predetermined time, and activating the compressor, if the pressure is below the predetermined pressure and if the vehicle is within the predetermined distance and/or is estimated to arrive at the destination within the predetermined time. A related vehicle, system, computer program (21) and computer program product (20) is also disclosed.
The invention relates generally to a method for controlling a compressor for a
compressed-air system in a vehicle. The invention also relates to a system, a computer program, a computer program product and the vehicle.
BACKGROUND OF THE INVENTION In vehicles, e.g. trucks, with air suspension, a compressor is provided to automatically
charge an air supply system, comprising air tanks and air bellows, both when the pressure in the air supply system reaches a predetermined minimum pressure and when an air- consuming activity, such as raising the vehicle or load transfer between tag axle and drive axle of the vehicle, is requested by an operator, e.g. the driver, of the vehicle.
US-6171065-B1 discloses a vehicle with pneumatic springs that can be filled with compressed air by a control unit operated compressor.
When a compressed-air consuming activity, such as raising or lowering the vehicle when unloading or loading the vehicle, is requested by the operator, e.g. by pressing a button
on a control box, and the compressor is automatically started, the pressure in the compressed-air system of the vehicle most often is insufficient or not optimal i.a. due to the fact that air has already been consumed during normal operation of the vehicle. This means that the activity requested by the operator will be time-consuming and that the operator will have to wait an extended time for the activity to finish, since it takes time
for the compressor to build up the pressure where the requested activity may be performed most effectively.
A way to solve this problem is to always automatically activate the compressor as soon as the pressure in the compressed-air system is lower than a predetermined optimal pressure
level for an activity that requires the highest pressure level in order to be performed in an
effective way. This solution is however normally not used in vehicles today, since the compressor, which normally directly or indirectly is driven by an internal combustion engine, substantially increases the fuel consumption of the vehicle. A frequent use of the compressor naturally also decreases the service life of the compressor.
SUMMARY OF THE INVENTION The object of the invention is to save time for the operator without substantially increasing the fuel consumption of the vehicle.
The invention relates to a method for controlling a compressor for a compressed-air
system in a vehicle. The method comprises the following steps: selecting at least one destination to which the vehicle is to be driven and brought to a standstill and where a compressed-air consuming activity is intended to be activated, calculating a distance from the vehicle to the destination and/or a time for the vehicle to arrive at the destination,
measuring a pressure in the compressed-air system, determining if the pressure is below a predetermined pressure adapted for the compressed-air consuming acti...