Quantitative dispensing of an automatic liquid dispenser is one of its key functions, involving highly precise liquid control and measurement.

Volume measurement

The core of quantitative dispensing is to accurately measure the volume of liquid. To achieve this, automatic liquid dispensers use advanced sensor technology, often using volume sensors or flow rate sensors.

Volume Sensor: This sensor directly measures the volume of liquid flowing through the system. Once the set target volume is reached, the system stops dispensing the liquid exactly. Volume sensors are usually based on fluid transmission methods such as peristaltic pumps and plunger pumps, which can achieve high-precision volume measurement.

Flow rate sensor: The flow rate sensor monitors the flow rate of liquid through the pipe and, combined with the dispensing time, calculates the actual dispensed volume. This approach is suitable for more complex liquid distribution systems, such as multi-channel liquid handling systems.

Precision valve control

In order to achieve accurate quantitative distribution, the automatic liquid dispenser uses a sophisticated valve control system. These valves are usually solenoid valves, capable of precise switching based on preset control signals. The valve's switching speed and response time are critical to ensuring accurate volume control.

Control Signal: A control signal generated by an embedded computer system tells the valve when to open and close. These signals are calculated based on the target volume and flow rate set by the user and ensure accurate dispensing of liquid within the set time.

System Calibration and Calibration

In order to ensure the accuracy of quantitative dispensing, automatic liquid dispensers are usually equipped with system calibration and correction functions. This includes regularly checking and adjusting sensor accuracy to prevent the accumulation of system errors.

Volume Calibration: The user can calibrate the system by entering a known standard liquid volume. This way, the system can adjust based on actual measurements, improving distribution accuracy.

Flow rate correction: The accuracy of the flow rate sensor can be corrected by comparison with a standard liquid of known flow rate. This helps ensure that the volume of liquid dispensed is consistent with the user's expectations.

Temperature and pressure compensation

Changes in temperature and pressure of a liquid may affect its density and fluidity, so some advanced automatic liquid dispensers are also equipped with temperature and pressure sensors and compensate during the dispensing process.

Temperature compensation: According to the temperature change of the liquid, the system can adjust the density of the liquid to ensure that the measured volume is true.

Pressure Compensation: Pressure changes can cause fluctuations in liquid flow rate. By monitoring the pressure inside the system and adjusting the opening and closing of the valve accordingly, flow rate stability can be maintained.