Dryer regeneration method for air suspension system
An air suspension system is provided with air spring devices, a pressure accumulation tank, a compressor device that supplies compressed air at least to the pressure accumulation tank, and that includes an electric motor, a pump device, and a dryer, and a control device that performs a vehicle height increase control, a vehicle height decrease control, an air suction control, and a regeneration air discharge control. The control device performs a heat accumulation control, by actuating the pump device with the communication between the compressor device and the air spring devices being blocked, supplying the compressed air discharged through the dryer to the pump device to be circulated, and accumulating heat of compression of the compressed air in the dryer, to regenerate the dryer.
1. A dryer regeneration method for an air suspension system, which comprises an air spring device provided with an air chamber and mounded on each wheel of a vehicle,
a pressure accumulation tank that supplies compressed air to the air spring device,
a compressor device that supplies the compressed air at least to the pressure accumulation tank, and that includes an electric motor served as a power source, a pump device driven by the electric motor to produce the compressed air, and a dryer that dries the compressed air produced by the pump device, and
a control device that performs a vehicle height increase control by communicating the pressure accumulation tank with the air spring device to supply the compressed air to the air chamber, a vehicle height decrease control by communicating the air spring device with the compressor device to discharge the air in the air chamber through the compressor device, an air suction control by communicating the compressor device with the pressure accumulation tank to supply outside air to the pressure accumulation tank, and a regeneration air discharge control by communicating the pressure accumulation tank with the compressor device to discharge the air in the pressure accumulation tank to the outside through the dryer, wherein
the control device performs a heat accumulation control, by driving the pump device, with the communication between the compressor device and the air spring device being blocked, supplying the compressed air discharged through the dryer to the pump device to be circulated, and accumulating heat of compression of the compressed air in the dryer, to regenerate the dryer.
2. The dryer regeneration method for the air suspension system as recited in claim 1 , wherein the control device performs the heat accumulation control before the regeneration air discharge control, and before or after the air suction control.
3. The dryer regeneration method for the air suspension system as recited in claim 1 , wherein a temperature sensor is provided for detecting a temperature of the outside air supplied from the compressor device to the pressure accumulation tank, and wherein
the control device determines necessity of the heat accumulation control based on at least a result detected by the temperature sensor.
4. The dryer regeneration method for the air suspension system as recited in claim 3 , wherein a humidity sensor is provided for detecting a humidity of the outside air supplied from the compressor device to the pressure accumulation tank, and wherein
the control device determines necessity of the heat accumulation control based on the results detected by the humidity sensor and temperature sensor.
5. The dryer regeneration method for the air suspension system as recited in claim 4 , wherein the control device adjusts a performing duration of the heat accumulation control based on the results detected by the humidity sensor and temperature sensor.
6. The dryer regeneration method for the air suspension system as recited in claim 1 , wherein the compressor device comprises;
an atmosphere suction port that suctions the atmosphere into the pump device,
a discharge port that discharges the compressed air of the pump device through the dryer, and
a back pressure introduction port that introduces the air in the air chamber and the air discharged through the dryer, and
the air suspension system comprises;
a first flow passage that communicates the pressure accumulation tank with the air chamber,
a control valve disposed in the first flow passage, and
a second flow passage that communicates a position between the control valve and the pressure accumulation tank with the back pressure introduction port, and that communicates the discharge port with the pressure accumulation tank, and wherein
the control device controls opening and closing the control valve to control the air supplied to and discharged from the air spring device, and controls opening and closing the second flow passage to perform the heat accumulation control.
7. The dryer regeneration method for the air suspension system as recited in claim 6 , wherein the air suspension system comprises;
a circulation passage configured by the first flow passage and the second flow passage, to circulate the compressed air by supplying the air discharged through the dryer to the pump device, and
a switching device that opens and closes the circulation passage according to the control performed by the control device.
8. The dryer regeneration method for the air suspension system as recited in claim 7 , wherein the switching device comprises a switching valve that opens and closes the circulation passage.
9. The dryer regeneration method for the air suspension system as recited in claim 8 , wherein the switching device further comprises;
a three-port two-position changeover valve, which is arranged in parallel with the switching valve, and disposed between the discharge port of the compressor device and the pressure accumulation tank, and which provides a first position that communicates the discharge port of the compressor device with the pressure accumulation tank, and that blocks the communication between the pressure accumulation tank and the first flow passage, and
a second position that communicates the pressure accumulation tank with the first flow passage, and that blocks the communication between the discharge port of the compressor device and the pressure accumulation tank, so that the first position or the second position is selected by the control device.
10. The dryer regeneration method for the air suspension system as recited in claim 7 , wherein the switching device comprises;
a three-port three-position changeover valve, which is disposed between the discharge port of the compressor device and the pressure accumulation tank, and which provides a first position that communicates the discharge port of the compressor device with the first flow passage, and that blocks the communication between the discharge port of the compressor device and the pressure accumulation tank,
a second position that communicates the discharge port of the compressor device with the pressure accumulation tank, and that blocks the communication between the pressure accumulation tank and the first flow passage, and
a third position that communicates the pressure accumulation tank with the first flow passage, and that blocks the communication between the discharge port of the compressor device and the pressure accumulation tank,
so that one of the first to third positions is selected by the control device.
11. The dryer regeneration method for the air suspension system as recited in claim 6 , wherein the air suspension system comprises;
a first supply-discharge switching valve, which is connected to the first flow passage between the pressure accumulation tank and the control valve, and connected to the discharge port of the compressor device,
a first tank switching valve which is disposed in the second flow passage between the discharge port of the compressor device and the pressure accumulation tank, and
a second supply-discharge switching valve and a second tank switching valve, which are disposed in the first flow passage between the control valve and the pressure accumulation tank, and which are arranged in parallel with the first supply-discharge switching valve and the first tank switching valve, wherein
a position between the second supply-discharge switching valve and the second tank switching valve is connected to the back pressure introduction port of the compressor device, and a position between the first supply-discharge switching valve and the first tank switching valve is connected to the discharge port of the compressor device, and wherein
the control device controls opening and closing the first and second tank switching valves, or opening and closing the first and second supply-discharge switching valves, to perform the heat accumulation control, so that the compressed air discharged from the discharge port through the dryer is introduced into the back pressure introduction port through the second flow passage to be circulated, to accumulate the heat of compression of the compressed air in the dryer.