JP3152539B2 - High-speed tape feeder - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-speed tape feeder in a magnetic recording / reproducing apparatus for recording information on a magnetic tape using a rotary cylinder, such as a video tape recorder, and more particularly to a rotary tape with a magnetic tape wound around the rotary cylinder. The present invention relates to a high-speed tape feeder for running a magnetic tape at high speed.

[0002]

2. Description of the Related Art Conventionally, as a high-speed tape feeder for moving a magnetic tape at a high speed without unloading the magnetic tape from a rotating cylinder in order to shorten the transition time of an operation mode, Japanese Patent Laid-Open Publication No. Hei.
11B15 / 467). In this device, the pinch roller does not press the capstan against the capstan, but rotates the reel base to run the magnetic tape at high speed.

[0003]

However, when the magnetic tape is wound around the rotating cylinder and the magnetic tape is run at a high speed without pressing the pinch roller, the torque from the supply side and the winding side and from both reel bases is increased. Is directly applied to the rotating cylinder, so that the load on the cylinder motor becomes very large, the number of rotations decreases, and in some cases, the cylinder may stop. In particular, when a brushless and sensorless DC motor is used as a cylinder motor, the rotation cylinder is easily stopped if the load applied to the rotation cylinder increases even a little. Therefore, the operation mode transition time cannot be reduced as desired.

The present invention is directed to a high-speed tape feeder for rotating a magnetic tape at a high speed by rotating a reel base in a state where a magnetic tape is wound around a rotary cylinder. The purpose is to prevent.

[0005]

A high-speed tape feeder according to the present invention is a high-speed tape feeder for running a magnetic tape at a high speed by rotating a reel base with a magnetic tape wound around a rotary cylinder. A rotation number detecting means for detecting the rotation number of the rotating cylinder, a pinch roller pressing means for pressing the pinch roller against the capstan, and detecting that the rotation number of the rotating cylinder has decreased to a predetermined value or less by the rotation number detecting means. In this case, there is provided a control means for pressing the pinch roller by using the pinch roller pressing means.

[0006]

The pressure applied to the pinch roller reduces the load applied to the rotary cylinder, and the rotary cylinder rotates normally. When the pinch roller is pressed, the running speed of the magnetic tape temporarily decreases, but does not cause an increase in the mode transition time as in the related art. Further, since the rotation speed of the rotary cylinder does not frequently decrease, it hardly affects the magnetic tape feeding time.

[0007]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a functional block diagram showing an embodiment of the present invention. In the figure, reference numeral 1 denotes a rotary cylinder on which a magnetic head (not shown) is mounted and which is rotated by a cylinder motor 2. Reference numeral 3 denotes a magnetic tape which is wound around the supply reel 4 and the take-up reel 5 and wound around the rotary cylinder 1 with guide pins 6 and 7. Under the supply reel 4 and the take-up reel 5, a supply reel base 8 and a take-up reel base 9 are provided, respectively.
There is a capstan motor 10 and a timing belt 1
1 is driven by a swing idler 12 driven through the shaft 1. Reference numeral 13 denotes a pinch roller, which is pressed by the pinch roller pressing means 14 to the capstan 10a with the magnetic tape 3 interposed therebetween as necessary. The pinch roller pressing means 14 is constituted by a cam, a plunger, and the like driven by a loading motor.

On the other hand, reference numeral 15 denotes a rotation speed detection circuit for detecting the rotation speed of the rotary cylinder 1, to which an FG signal from the cylinder motor 2 is input. The output of the rotation speed detecting circuit 15 is input to a control circuit 16, which controls the capstan motor 10 and the pinch roller pressing means 14.

Next, the operation of the embodiment will be described with reference to the flowchart shown in FIG. When the high-speed feed mode or the high-speed rewind mode is set in the control circuit 16, the pinch roller 13 is moved to the capstan 1 by the pinch roller pressing means 14.
0a (S1). And the capstan motor 1
0 is rotated at a high speed to rotate the supply reel table 8 or the take-up reel table 9 at a high speed (for example, the rotation speed is gradually increased to 20 times speed), and the magnetic tape 3 is fed at a high speed (S
2). Then, the rotation number detection circuit 15 uses the rotation cylinder 1
Is detected (S3), and if the number of revolutions does not fall below the predetermined value, the control circuit 16 detects whether the high-speed feed mode or the high-speed rewind mode is canceled or the transition to another mode is set. (S4). If the setting of the mode transition is detected, the operation of the high-speed fast-forward mode or the high-speed rewind mode is terminated, and the mode is shifted to another mode.

If it is detected in step S3 that the rotation speed of the rotary cylinder 1 has fallen below a predetermined value, the rotation speed of the capstan motor 10 is adjusted so that the magnetic tape 3 is not hindered even if the pinch roller 13 is pressed. For example, the rotation speed is reduced to about 5 times speed (S5), and then the pinch roller 13 is moved to the capstan 1 by the pinch roller pressing means 14.
0a (S6). The distance that the pinch roller 13 moves between pressure bonding and non-pressure bonding is usually about several mm,
The operating time of the loading motor or plunger is very short. S5 is unnecessary if the magnetic tape 3 does not interfere with the magnetic tape 3 even when the pinch roller 13 is pressed in a high-speed running state. Then, when the pinch roller 13 is pressed, the torque from the supply side and the winding side, which are directly applied to the rotary cylinder, from both reel bases is reduced,
The rotation speed of the rotary cylinder 1 is about to return to the original value. If it is detected that the rotation speed of the rotary cylinder 1 has returned to the normal value, that is, the predetermined value in S3 (S7), the process returns to the preceding stage of S1.

FIG. 3 is a timing chart showing the operation of the embodiment. In the figure, the number of rotations of the capstan motor 10 is shown as a double speed number where the speed during normal reproduction is 1.

Although the embodiment of the present invention has been described above, it goes without saying that the reel base may be driven by a motor dedicated to the reel base instead of the capstan motor.

[0014]

According to the present invention, in the high-speed feed mode or the high-speed rewind mode in which the pressure of the pinch roller is released,
Even when the rotation of the rotary cylinder is abnormally reduced or stopped, it is possible to continue feeding the magnetic tape without causing a system down. In addition, since the tape is normally wound around the rotating cylinder and the rotation speed and rotation direction of the rotating cylinder are the same as the reproducing state, the transition from the high-speed feed mode or the high-speed rewind mode to the reproducing mode is also performed promptly. A high-speed tape feeder capable of providing a high-speed tape feeder, the effect of which is great.

[Brief description of the drawings]

FIG. 1 is a functional block diagram showing an embodiment of the present invention.

FIG. 2 is a flowchart showing the operation of the embodiment of the present invention.

FIG. 3 is a timing chart showing the operation of the embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Rotating cylinder 2 Cylinder motor 3 Magnetic tape 8 Supply reel stand 9 Take-up reel stand 10 Capstan motor 10a Capstan 13 Pinch roller 14 Pinch roller crimping means 15 Revolution detection circuit 16 Control circuit

Claims (1)

(57) [Claims] 1. A high-speed tape feeder for rotating a magnetic tape at a high speed by rotating a reel base with a magnetic tape wound around a rotary cylinder, wherein a rotation speed detecting means for detecting a rotation speed of the rotary cylinder; Pinch roller pressing means for pressing the roller against the capstan; and control for pressing the pinch roller using the pinch roller pressing means when the rotation speed detecting means detects that the rotation speed of the rotary cylinder has decreased to a predetermined value or less. And a high-speed tape feeding device.