| 摘要 |
<p>PROBLEM TO BE SOLVED: To materialize a trigger unaffected by a change in a direct current component of vibration acceleration and to enable an accurate threshold value to be set.SOLUTION: A vibration sensing device (10) includes: vibration detecting means (30); temporary storage means (104) for temporarily storing vibration data; recording means (105) for recording a part of the temporarily stored vibration data; and calculation and control processing means (102) which, when the vibration data exceeds a trigger level, determines the recording start/end time of the vibration data with the exceeding of the vibration data as a trigger, which extracts the vibration data from the recording start time to end time from the temporary storage means and records the extracted data in the recording means, calculates a direct current component of the vibration data measured for a prescribed time from a prescribed timing, sets the direct current component as a first reference level serving as the reference of a trigger level, compares the magnitude of the reference level and the vibration data within a prescribed time after the reference level is set, and updates the reference level by adding and decreasing an adjustment value to and from the reference level so as to follow the temporal fluctuation of the vibration data based on the comparison result at a prescribed time interval.</p> |
