| 摘要 |
<p>PURPOSE:To suppress the vibration of a tape by providing a sensor to detect the vibration in the normal direction of a tape surface and an excitation device to supply the vibration with phase opposite to that of the vibration on the tape surface in hilical scanning system VTR and DAT, etc. CONSTITUTION:The tape is traveled by winding the tape 4 across a drum 1 and while guiding it with a guide post 6, etc., however, at this time, a head 11 mounted at a rotary drum 10 constituting the drum 1 hits the tape 4, which generates the vibration in the tape 4. Therefore, when the light generated from the LED of a photonic sensor 2 is reflected on the surface of the tape 4, and converted to an electric signal at the light-reception part of the sensor 2, and data is fetched in a phase inversion circuit 5, and the phase and amplitude are inverted, an excitation signal is applied to the excitation device 3 provided newly. At such a case, the excitation device 3 is fixed at a pedestal not shown in figure with a fixing member 32, and a voltage is applied to a laminate type piezoelectric element 33 constituting the excitation device, and it is displaced in a thickness direction, and the surface of the tape 4 is vibrated with a pressing member 31, thereby, the vibration of the tape can be reduced.</p> |
