Automatic weighing system and sampling method thereof

Abstract

The invention aims to provide a system capable of realizing high-precision automatic sampling and avoiding cross contamination of samples and a sampling method thereof. The automatic weighing system comprises a sampling module, a weighing module and a cleaning module. The sampling module comprises a sampling rod and a driving device, wherein the driving device is used for controlling rotation andmovement of the sampling rod, a detachable sampling head is arranged at the bottom of the sampling rod, and a groove is formed in the sampling head and used for sampling; the weighing module is used for weighing the samples taken by the sampling rod; and the cleaning module is used for cleaning the sampling rod. The invention also discloses a sampling method of the automatic weighing system. The method has the advantages that a piecewise fitting function is constructed according to samples with different densities, so that an error between a sampling amount prediction value and an actual measurement value is better controlled, and the sampling precision is guaranteed; and the sampling centrifugal speed and time are accurately controlled, and the problem that different sampling rods need tobe replaced when the sample density is different is solved.

Description

technical field [0001] The invention relates to an automatic sampling and weighing device for powder samples. Background technique [0002] At present, in the wet chemical analysis, for the analysis of powder samples, the first step is to take a sample, and then weigh the sample to achieve an accurate sampling amount, then acid-dissolve and digest the sample, and finally carry out the solution sample. analyze. [0003] In the above process, the routine operation is to manually use a sample spoon to enter the sample bottle, and manually perform micro-sampling. The sampling volume is usually 0.1g to 0.5g, and the control accuracy is 0.00001g. For samples with relatively high density, the volume is relatively small. Small, and the diameter of the sample tube used to place the powder is small, so this operation is currently carried out by manual precise control sampling. After the sampling is completed, when the next sample is taken, the sample spoon needs to be wiped clean wi...

AI Technical Summary

Problems solved by technology

[0005] The traditional automatic operation design scheme is to simply control the sample spoon through the manipulator, and simulate the manual sampling method to realize automation. The sampling accuracy is low, and the samples with different densities need to be accurately sampled. The sample spoon of different specifications and sizes needs to be sampled, which is complicated to operate and not easy to clean. There are also some manufacturers who use manipulators to simulate human hand shaking and dump samples for weighing. The control accuracy is poor, and the samples are scattered in a large area, which cannot enter the sample tubes used in conventional chemical analysis.

Images