汽车转向传动轴扭转疲劳寿命试验台设计

Design of Test Stand for Torsional Fatigue Life Test of Vehicle Steering Driveshaft

针对汽车转向传动轴扭转疲劳寿命的测试,设计了基于PIC16F877单片机的试验台,给出了具体的试验方法,在传动轴与方向盘联接的一端,利用步进电机驱动传动轴,模拟方向盘正反方向的转动,传动轴另外一端,由程控电源控制磁粉制动器,产生扭转负载,与磁粉制动器串联安装有扭矩传感器,能对试验负载进行检测反馈,单片机与程控电源通过串口通信,能自动调节程控电源输出的电流大小,从而使磁粉制动器输出的扭矩负载恒定;该系统测试数据准确,具有试验次数记忆和故障报警功能,成本低,具有实用价值。

For the purpose of torsional fatigue life test of vehicle steering driveshaft,the test stand was designed on the basis of PIC16F877 microcontroller and the specific test methods were given.By using stepper motor to actuate the driveshaft,the clockwise and counterclockwise motions of steering wheel were stimulated on one end of the driveshaft connecting steering wheel.On the other end of the driveshaft,torsional load was produced with magnetic powder brake controlled by programmable power supply.The torsion sensor,which was installed in series with the magnetic powder brake,was able to detect and feed back the test load.The microcontroller communicated with the programmable power supply via the serial port and was capable of automatically regulating the magnitude of current from the programmable power supply.In this way,the torsion load from the magnetic powder brake was kept constant.This cost-effective system with practical value has achieved accuracy of data and functions of test-time memory and fault alarm.