US 6,771,883 B2 · Device and method for controlling tape travelling speed and medium for recording its control program

Abstract

The travelling speed of a magnetic tape is controlled without considering a detection error caused by the slackening of a magnetic tape or the like. A microcomputer 10, immediately after starting a fast-feeding operation, starts a running rotation of feeding and winding reels 44, 45 (step S205), calculates an N value based on reel pulses and sets an acceleration target (step S210, S215) and simultaneously reads the N value immediately before the previous stop of the rotation from RAM and compares the read N value with the current N value (step S225, S230), prohibits the acceleration of the feeding and winding reels 44, 45 after confirming that the error does not fall within 25% (step S235) whereby when the videotape is rotated to the leader or the trailer, the videotape is prevented from being applied with an excessive load so that damages on the videotape can be reduced.

Claims7

Dependent claims

A tape travelling speed control device equipped with a supply reel pedestal for driving a supply reel and a winding reel pedestal for driving a winding reel, of a videotape, said device comprising:

rotation detection elements for outputting reel pulses when the supply reel pedestal and the winding reel pedestal are rotated at a predetermined angle respectively,
RAM for storing a ratio of intervals of the reel pulses outputted by the respective rotation detection elements, and
a CPU for controlling the tape travelling speed by calculating the ratio between the intervals, controlling to store the ratio to the RAM, comparing the ratio detected before the tape is stopped with the ratio detected after the tape is traveled, and determining that the ratio is correct when an error of the ratios is smaller than a threshold value.

A tape travelling speed control device comprising:

a reel rotational state detection unit for detecting a rotational state of a tape reel for making a magnetic tape travel,
a reel rotational state storing unit for storing a rotational state of the tape reel detected by said reel rotational state detection unit at appropriate times, and
a tape travelling speed control unit for comparing the stored rotational state with the latest rotational state and controlling the travelling speed of said magnetic tape in accordance with whether the rotational state falls within a normal range based on a difference between the stored rotational state and a current rotational state, and
wherein said reel rotational state detection unit detects the ratio of rotation between the feeding reel for delivering said magnetic tape and the winding reel for winding said delivered magnetic tape as the rotational state;
said reel rotational state storing unit stores the ratio of rotation detected by said reel rotational state detection unit at appropriate times;
and
said tape travelling speed control unit compares the ratio of rotation stored in said reel rotational state storing unit with the latest ratio of rotation, and controls the travelling speed of said magnetic tape in accordance with whether a comparison result falls within a normal range based on a difference between the stored rotational state and the current rotational state.

4 more elements

Dependencies are inferred from the claim text.

Device and method for controlling tape travelling speed and medium for recording its control program

Life of this patent

Device and method for controlling tape travelling speed and medium for recording its control program

Life of this patent

Abstract

Claims7