| 摘要 |
PURPOSE:To display the remaining time precisely by detecting the rotation period of a payoff side reel, making a comparison between the past and current input signals and inputted a signal of a monotone side to a trailing stage, and updating the signal of the trailing stage. CONSTITUTION:The rotation period of the payoff side reel is detected by a signal detection part 4 and inputted to a correction part 7, wherein the signal is A/D-converted by an A/D converter 13 to store up-to-date information JN on the rotation period in a storage circuit 10. The storage circuit 12 is further stored with the past informtion JO on the rotation period inputted to an arithmetic part 5 already. A comparing circuit 11 makes a comparison between the JN and JO and when TW1<TW2 where TW1 and TW2 are corresponding periods, the JN is inputted to the arithmetic part 5 to calculate the remaining tape time, thereby updating the contents of the storage circuit 12 to the JN. When TW1> TW2, the JO is inputted to the arithmetic part 5 to calculate the remaining time, holding the JO continuously. Said operation is repeated similarly. Consequently, the remaining time decreasing monotonously is displayed at a display part 6 to display the precise remaining time while an error due to the flection and irregular winding of the tape is prevented. |
