| 摘要 |
Apparatus sensitive to tension or flexing stress comprises a belt (13) with a tension sensor (22) fitted along its length including a loop (19) connected to a movable member (20). The tension sensor (22) includes a microswitch, a delay circuit and an oscillator. In use the belt (13) is adjusted to fit snugly when the wearer is comfortably supporting his or her own abdomen with the abdominal muscles. Relaxation of the abdominal muscles results in a slight enlargement of the waist causing closure of the microswitch which, after a short delay determined by the delay circuit causes the oscillator to generate an audible output signal to warn the wearer that muscle relaxation has taken place. Other warning signals may be produced, and the belt may be a seat belt for sensing driver alertness. <IMAGE> |
