Liquid ejection device for a vehicle washing system and method for its operation

A liquid ejection device for a vehicle washing system, the device comprising:

• a reservoir volume;
• a first supply line coupled upstream to the reservoir volume for supplying a first liquid with a first supply rate;
• a second supply line coupled upstream to the reservoir volume for supplying a second liquid with a second supply rate;
• a removal line coupled downstream to the reservoir volume with a blocking device for blocking a liquid flow through the removal line;
• a detection unit for detecting a liquid volume in the reservoir volume and a mixing ratio of the liquids introduced into the reservoir volume;
• a removal device for ejecting the liquid found in the reservoir volume with an ejection rate through an ejection element coupled to the removal line;
• a control unit which is coupled to the detection unit and the removal device and is set up to start an ejection process by means of the removal device upon reaching a predetermined liquid volume and a predetermined mixing ratio;
• and
• a pressure detection element for detecting an internal gas pressure in the reservoir volume, the pressure detection element being coupled to the detection unit,
• wherein the reservoir volume is sealed in a gas-tight manner such that introducing the first liquid and/or the second liquid into the reservoir volume leads to an increase of the internal gas pressure in the reservoir volume.

A liquid ejection device for a vehicle washing system, the device comprising:

• a reservoir volume;
• a first supply line coupled upstream to the reservoir volume for supplying a first liquid with a first supply rate;
• a second supply line coupled upstream to the reservoir volume for supplying a second liquid with a second supply rate;
• a removal line coupled downstream to the reservoir volume with a blocking device for blocking a liquid flow through the removal line;
• a detection unit for detecting a liquid volume in the reservoir volume and a mixing ratio of the liquids introduced into the reservoir volume;
• a removal device for ejecting the liquid found in the reservoir volume with an ejection rate through an ejection element coupled to the removal line;
• and
• a control unit which is coupled to the detection unit and the removal device and is set up to start an ejection process by means of the removal device upon reaching a predetermined liquid volume and a predetermined mixing ratio,
• wherein the control unit is further coupled to a supply device for the second liquid,
• the supply device comprises a pressure detection element for detecting an internal gas pressure, the pressure detection element being coupled to the detection unit, and
• the pressure detection element is set up to detect a power consumption of the supply device and to determine the internal gas pressure by means of the power consumption.