Development Of PTCR's Automatic Voltage-withstanding Tester

Thermistors can be divided into positive temperature coefficient of resistance(PTCR)and negative temperature coefficient of resistance(NTCR)according to the different temperature coefficient.The rapid development of new energy vehicles,air conditioning and other industries has brought about a significant increase in PTCR output,but also puts forward strict standards for the test of PTCR.At present,the level of voltage-withstanding test of domestic PTCR manufacturers varies,and some PTCR manufacturers have fast testing speed and high production efficiency,while some PTCT manufacturers have poor testing speed and production efficiency.This paper is focused on the voltage-withstanding test of the positive temperature coefficient of resistance.Based on improving the production efficiency,this paper designs an automatic PTCR voltage-withstanding tester which can be suitable for large-scale production enterprises.The paper discusses the mechanical structure,hardware circuit and system software in detail.For the mechanical structure,three design schemes are implemented through simulation by using 3D drawing software named Solid Works,and then a final design scheme,which can be suitable for manufacturing,with high automation rate is obtained by comparing and analyzing.The scheme divides the whole test system into three parts,automatic feeding,automatic testing and automatic sorting.Mechanical design which uses the manipulators,the driving device such as motor and the pneumatic device such as suction cup improves the degree of automation.For the hardware circuit,the final scheme uses circuit design software named Altium Designer to improve the original design scheme used in old tester,and make an in-depth discussion on the selection of hardware.For the software system,the upper computer software and MCU software are designed.The upper computer is developed based on Qt,and the MCU software,which can execute the instructions sent by the upper computer,is developed based on C language combined with software named Keil.The design in this article realizes 16 stations on each test fixture and tests 16 samples at the same time.The test speed can reach 4 times more than the previous generation voltage-withstanding tester,which greatly improves the test efficiency.With the assistance of EDA,CAD and other design software,it can be seen that the whole system designed in this paper has the characteristics of highly streamlined operation,which is suitable for industrial mass production.Each functional module can be maintained independently,which can reduce the maintenance and repair cost during operation.High automation rate can effectively reduce the input of labor costs.