| 摘要 |
PURPOSE:To minimize damage to a tape by providing a piezoelectric element detector outputting a signal having an amplitude level in response to tape deformation in slide- contacting with the running tape, a level comparator circuit outputting an abnormal signal in response to the abnormal deformation, and a counter outputting a tape fault signal, to detect earlier the generation of a trouble of tape deformation. CONSTITUTION:The piezoelectric element detector U1 is provided in the vicinity of the outlet of tape of the mechanism part easy to cause the deformation of the tape T. When an intermittent abnormal deformation T' such wrinkle and fold occurs to the tape T and the abnormal deformation T' is run while being slid to a slider 3 at a position provided with the piezoelectric element detector U1, a plate spring 1 is bent in following to this intermittent abnormal deformation T'. Stress is applied to the piezoelectric element 2 by this bending, a pulse form signal having a large amplitude in response to the abnormal deformation is produced intermittently, and an irregular vibrating signal e1 appears from an amplifier AMP. The vibrating signal e1 is compared with a reference voltage generating circuit U3 at a level comparator circuit U2 and a comparison output e3 is obtained. Then a prescribed operation is conducted, and after tape fault is detected, a processing such as stopping of the device operation is conducted and the further damage on the tape is prevented. |
