| 摘要 |
A method and apparatus for testing wire and, more specifically, testing the wire thickness and the wire roll of a trolley wire. The apparatus includes a jig assembly connected to a data acquisition system carried by a mobile unit. The jig assembly includes a transducer probe which transmits and receives an ultrasonic signal and an encoder which provides a pulse train corresponding to distance traveled. The ultrasonic signal is transmitted into the trolley wire and a reflected wave is received. The data acquisition system includes an ultrasonic scope, an analog to digital converter, a central processing unit, and a divider circuit. The ultrasonic scope provides a time analog signal based on the time of flight comparison between the transmitted ultrasonic signal and the reflected wave. The time analog signal is converted to a digital signal through an analog to digital converter. A trigger pulse is provided by a divider circuit based on a predetermined number of pulses from the encoder. In response to the trigger pulse, the digital signal is processed by the central processing unit to provide a corresponding wire thickness of the trolley wire. If the trolley wire is twisted, the reflected wave will be lost and the central processing unit will void the sample. The central processing unit compiles, organizes, summarizes, and stores the data in a useful form. A couplant fluid, for example, water, is supplied continuously to the surface of the segment of the trolley wire under test via a water reservoir within the transducer probe subassembly.
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