| 摘要 |
<p>PURPOSE:To prevent the crosstalk due to the magnetic flux leakage by providing a light emitting part provided outside a rotary drum and a photosensitive switching part to select a prescribed magnetic head provided in the rotary drum and connect it to a single rotary transformer. CONSTITUTION:On a rotary drum 10, two magnetic heads 11 and 12 provided in the interval of 180 deg. mutually are fitted. At the lower side of the rotary drum 10, a coaxial fixed drum 13 fixed at the main body of a device is mutually faced. Switching parts 15 and 16 provided in the rotary drum 10 are synchronized to the rotation of the rotary drum 10 and a magnetic head 11 are respectively switched. Other edge of the switching parts 15 and 16 is connected to a primary coil side 17a of a rotary transformer 17. Photosensitive switching parts 15 and 16 obtains the energy by the light from a light emitting part 20 provided on the upper direction of the rotary drum 10 and execute the switching action. For this reason, it is not necessary to supply a head switching signal and a power source for switching into the rotary drum 10.</p> |
