Research And Development On Control System For Loading Of Calibration Device

Calibration of weighing device is widely used in industry measurement,which is the foundation of ensuring unified measurement industry benchmark and normal operation.Piston gauge is one kind of the common use of the calibration of weighing device by calibration pressure with weights.Weight or pressure is the physical reference of weighing calibration,therefore weight loading or pressure loading is one of the important aspects of instrument calibration.Generally weight loading is performed by weights combination and weights adding and pressure loading is performed by controlling pressure regulator and supercharger.At present domestic automation level of piston gauge is limited,especially in the field of super high pressure of more than 100 MPa.Weights loading,valve switching and oil pump operating rely on manual operation,which result in operation process trivial and lower work efficiency.In order to solve this kind of situation,piston gauge within 250MPa is studied and automation control scheme is proposed in the dissertation.Based on the mechanical modifications of the existing piston gauge,control system of auto weight loading and pressure loading is developed,completing piston gauge automation operating tasks.The system not only can be used for the piston gauge,but also for other calibration device system with pressure loading and weight loading.The control system with pressure loading and weight loading studied in the paper consists of master computer:MCGS touch screen and slave computer:controller by STM32 MCU.Free combination of hanging basket weights and order loading of disc weights are finished by servo motors.The step-up and step-down process of oil pressure range from 5 to 250 MPa is finished by servo motor,clutches,control valves,pressure regulator and multiplier.Using eddy current displacement sensor,the effective balance position of the piston is tested,realizing standardization and calibration...