The Design Of Automatic Control System For Laser Particle Sizer

The size of the particles is called particle size. Particle size distribution is used to measuredifferent size particles of the proportion of the total particles, while laser particle sizer is ainstrument to detect particle size distribution. The characteristics of particle size haveincreasingly important role in research and production, so the detecting technology of theparticle is becoming more and more important. While many kinds of laser particle sizers areproduced with the development of the need.Corresponding device are needed to keep particles scattered state, because measuredparticle are put into the liquid well-distributedly, for example circulation and stirring. Theoperation of the products that is in the market now, is realized by the push-button in the panelsof the laser particle sizer which controls the equipments, while the processing of some deviceis matched by hand, while brings difficulty to people in the complex condition. In order torealize full-automation, some device, worked by hand, is remade control device working aselectromagnetic valve, so users operate buttons on host computer in the control room wherethe condition is good. The action of laser particle sizer can be controlled by thecommunication between host computer and lower computer which receives the orders of thehost computer.According to the low level of automation particle size analyzer, the new laser particlesizer of friendly human-machine interaction will be developed by the optimization of lowercomputer’s hardware circuit and controlling circuit of host computer.The main content of this paper include the following aspects:(1)The composition, working principle, development and applications of laser particlesizer is mentioned in this paper.(2)System software is compiled by VB, and the hardware parts configuration iscomposed by the hardware circuit that is related to the knowledge of single chipmicrocomputer, so the information of VB and single chip microcomputer is mentioned in thispaper.(3)Both of system software and hardware circuit is included in this paper. System software is composed manual and automatic parts, which is designed in logic layout on thebasis of principle of laser particle sizer. The single chip microcomputer’s sing, from the lowercomputer whose control command is sent from the control panel of the host computer, is sentto the periphery controlled device, so that the switches of agitator, inlet valve, ultrasonicmachine circulating pump and drain valve can be controlled. The inlet valve will be turnedoff,when sample reservoir’s water level which is detected by the sensor to control the highdegree of the water is detected by the single chip microcomputer getting to the index value，sothe automatic control of laser particle sizer can be implanted by the single chipmicrocomputer. Hardware circuit module is comprised by switching circuit as bidirectionaltriode thyristor. Automation control solutions is put forward based on the single chipmicrocomputer’s system according to the automatic demanding of the laser particle sizer.