DETECTION FOR GENERATION OF FATIGUE CRACKING IN RADIAL LOAD ENDURANCE TEST FOR WHEEL OF AUTOMOBILE

摘要

PURPOSE:To enable the detecting of a generation timing of a fatigue cracking by measuring a change in a distance between a wheel and a rotary drum during a endurance test. CONSTITUTION:When a wheel 18 having a tire 17 mounted thereon is pressed by a load of 500-2,000kgf on a rotary drum 13 rotating at a speed of 60-100km per hour with the driving of a hydraulic cylinder 15, an air pressure of the tire rises remarkably with thermal expansion of air within the tire so that a distance between the wheel and the drum expands to be stabilized. Here, wheel position detectors 19 and 20 are set to measure a distance between the wheel 18 and the drum 13 and a change in the distance is measured with a cracking generation detector 21. Then, the detector 21 detects the timing of generation of even a fine fatigue cracking precisely based on a change from a reference state at which the distance between the wheel and the drum with the thermal expansion of the air within the tire. Then, a radial load endurance can be evaluated depending on a total of revolutions or a total of running distance until a fatigue cracking occurs.