| 摘要 |
PURPOSE:To prevent a body to be tested from receiving excessive load or to prevent a test apparatus from getting into a control unabled state even if play or slide is generated in the body to be tested, by repeatedly applying load to the body to be tested at vibration frequency equal to and more than the resonance vibration frequency of a vibration system. CONSTITUTION:An objective rotary speed at the time of a test for vibrating a vibration system at vibration frequency equal to and more than the resonance vibration frequency thereof is set to a rotary speed setting device 30. When a start switch is closed, a variable speed motor 26 is rotated by the signal from a control circuit 28 and the rotary speed of the motor 26 is abruptly raised to the objective rotary speed. The vibration system consisting of a body 10 to be tested and a vibrating lever 2 is vibrated at vibration frequency equal to or more than resonance vibration frequency through a rotary eccentric weight 12. Because vibration frequency of forcible force is not changed abruptly even if skidding or play is generated in the body 10 to be tested and resonance vibration frequency becomes small, no excessive load is applied on the body to be tested. |
