The automatic sample changer used in X-ray diffractometers is a device used for automated sample replacement, aimed at improving the efficiency and accuracy of X-ray diffraction experiments.

Driven by an imported stepper motor and controlled by an imported Siemens programmable logic controller (PLC), there is no need for manual sample replacement. The system automatically measures samples continuously and saves data automatically. Multiple samples can be loaded at once for continuous measurement.

The main components of an automatic sample changer are:

Sample transfer mechanism: usually includes a conveyor belt, elastic pressing plate, and driving motor, responsible for sequentially transferring the test sample plates to the retrieval position.

Sample replacement mechanism: generally composed of clamping components, action driving components, and turntable, it can automatically replace the sample plate between the conveyor belt pick-up position and the diffraction instrument sample stage.

Sensor module: such as photoelectric sensor module and photoresistor sensor module, used to detect the position of the sample and the working status of the diffractometer, in order to control the circuit module to make corresponding control actions.

Control circuit module: Connect and control the collaborative work of the above-mentioned mechanisms and modules to ensure accurate and stable operation of the automatic sample changing process.

Power module: provides power support for the entire automatic sample changing device.

2. Working principle of automatic sample changer:

After the diffractometer completes the testing of the current sample, the sensor module detects the state change of the diffractometer shutter light and transmits the signal to the control circuit module.

After receiving the signal, the control circuit module activates the sample replacement mechanism to move it to the conveyor belt pick-up position and the diffraction instrument sample stage, and clamps the sample plates at the two positions respectively through the clamping parts.

Then, the sample replacement mechanism swaps the positions of the two sample plates to complete the sample replacement operation.

Next, the conveyor belt starts and transports the next sample board to the pick-up position, waiting for the next sample change.

3. Advantages and characteristics of automatic sample changer:

• Improve testing efficiency: It can automatically replace samples during the diffraction instrument testing process without manual intervention, greatly shortening the testing cycle and improving work efficiency.

• Reduce human error: avoid operational errors and mistakes that may occur when manually replacing samples, and improve the accuracy and reliability of test results.

• Instrument protection: reduces the possibility of instrument failure caused by frequent manual opening and closing of the diffractometer door, and extends the service life of the diffractometer.

• Suitable for testing a large number of samples: It can load multiple samples to meet the needs of continuous testing of a large number of samples, and is suitable for high-throughput detection in fields such as scientific research and production.

In summary, the automatic sample changer used in X-ray diffraction instruments is an efficient and accurate automated equipment that brings many conveniences and advantages to X-ray diffraction experiments, helping to improve experimental efficiency and quality.