Design On Sampler And Mechanical Device Of Dust Monitor Based On β-absorption-method

The dust measuring instrument based on β-ray method is free of dust type, particlesize, dispersion, shape, color, luster and other factors, and it can continuouslymonitor dust concentration in the air, and the results are dynamically displayed. Butit still have some shortcomings for using a source (about60μCi,2.2210~6Bq), thatis it has security risk and the volume for dust monitor based on β-absorption-methodis larger.According to these shortcomings, existing beta-ray dust instrument is studied,and the measurement procedures of existing beta-ray dust are improved. Theimproved measurement procedure is simpler, and improved measurementprocedures dust instrument is smaller in volume. At the same time, the experimentof the90Sr radioactive source through blank glass fiber filter paper is carried out.The experimental results show that the improvement of the measurement procedureis feasible. Program based on the measurement of improved beta-ray dust, Idesigned the exhaust of the holder of the sampling device, the exhaust pipe tocontrol mechanical devices, filter gear, shields, baffles and fixtures beta source,detector, detector fixed and protection devices. Three-dimensional map of thevarious parts is given in the paper, and the appendix gives three views of the variousparts. Sampler mechanical system model can be produced through the three views.Based on improved the measurement sequence of the β-ray Dust MonitorSampling process, I design pump’s control circuit, microprocessor control circuit ofthe electromagnet, stepper motor control circuit. I draw a suction pump, solenoidsand stepper motor control circuit schematics with software protel99se. Allowing forthe β-ray Dust Monitor Sampling control requirements, designs are made for the airpump, solenoid, stepper motor control program. With the Keil uVision3and ProteusSoftware, a joint simulation of the control circuit, the control program machine codeis loaded into the MCU control circuit, and the results are accurate and reliable.Finally, Sub-module verification for experimental sampling control system isconduced. The experimental results fully in line with the original designrequirements.