| 摘要 |
<p>PURPOSE:To enable the detection of changes in an object to be inspected with a compact apparatus requiring no skill, by striking the object being inspected with a hammer having a force detecting sensor or the like to detect a pulse width of a pulse waveform of the generated force or the like. CONSTITUTION:An object 10 to be inspected is struck with a hammer 1 having a force detecting sensor 2 or an acceleration detecting sensor near the tip thereof. An electrical signal of a pulse waveform detected with the sensor 2 during the striking is introduced into a pulse width calculating circuit 3 to be converted into a voltage B or a digital signal proportional to the pulse width. Here, when the normal part is struck with the hammer 1, the B value is stored into a reference pulse width memory section 5 as specified by a switch 4 to set a reference value B0. Then, the signal B and the reference value B0 are introduced to a comparator circuit 6 to calculate B-B0=C1 or B/B0=C2 and the value C1 or C2 is introduced to a display device 7. Thus, the outside is informed of a shift from the normal value by light or sound.</p> |
