| 摘要 |
PURPOSE:To attain the generation of a load waveform giving an effective fatigue to a sample to be tested by the constitution that a frequency is changed in response to the change in an amplitude of load by providing a memory storing a frequency signal having a prescribed relation of function to an amplitude signal. CONSTITUTION:A computer 1 fetches a random number from a random number generator 6, decides a frequency determined by an amplitude and a function table stored in a memory 5 and outputs waveform information to an interface 2. The interface 2 generates digital waveform information according to the command of the computer 1. A D/A converter 3 converts the digital waveform information into an analog signal and the test equipment 4 receiving the signal gives a load to a material. When the output waveform from the interface 2 reaches a maximum value, interruption is applied to the computer 1, the waveform output is stopped momentarily, the next random number is fetched and the amplitude and the frequency and decided. This procedure is repeated, and a random wave having, for example, a higher frequency with less amplitude is generated and nearly a constant fatigue is applied to the material. |
