JPH0441425B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a VTR device for recording or reproducing video signals in the field of magnetic recording.

2. Description of the Related Art Structures and Problems Therein In recent years, VTR devices have been widely used for transmitting or recording TV signals, recording data, and the like.

A conventional VTR device will be explained below.

Figure 1 shows the conventional U loading method.
This is a schematic plan view of a VTR device, with a solid line indicating when loading is completed and a broken line indicating when loading is started. 1 is a cassette, 2 is a magnetic recording tape, 3 is a rotating drum, 4 is a loading ring,
Reference numeral 5 denotes a drive gear for driving the loading ring, which is not shown in the drawing, but is driven by a motor or the like. Reference numeral 6 designates an entry-side regulating post, 7 an exit-side regulation post, 8 an entry-side drawer post, 9 a capstan, 10 a pinch roller, 11 a turn roller, and 12 and 13 posts.

The operation of the conventional VTR device configured as described above will be explained below.

When the cassette 1 is installed, the turn roller 11 and the pinch roller 10 on the loading ring 4 are
The magnetic recording tape 2 is located at the 2' position (the other posts 12 and 13 are omitted). Next, during loading, the loading ring 4 is driven by the driving gear 5, and the turn roller 11 comes into contact with the magnetic recording tape 2 at the position 2'.
While holding it, it is wound around the rotating drum 3, and the input side drawer post 8 moves from the position 8' to the position 8, and the input side magnetic recording tape 2 is pulled out and wound around the input side post 6, and the solid line This forms the traveling system shown in .

As shown in FIGS. 2 and 3, in this device, a lever 16 that rotates around a fulcrum 15 is rotated by a pin on a loading ring 4, and a photointerrupter 17 emits light and a light-receiving surface. The starting end and ending end are detected by blocking or opening. Normally, the motor (not shown) is driven by a constant voltage, so the loading ring 4 rotates at a constant rate because the driving gear 5 is rotated at a constant rate by the motor, and the magnetic recording tape 2 is wound around the rotating drum 3. and the loading is completed.

During unloading, the magnetic recording tape 2 is wound around the rotating drum 3 by rotation in the opposite direction to that of loading.

However, in the above configuration, the motor must be driven at a constant voltage, resulting in an overload on the magnetic recording tape 2 due to a sudden rise at the start of loading, or an overload on the magnetic recording tape 2 due to a sudden stop at the end of loading. There is occurrence of sagging in 2.
In order to avoid these, the rotational speed of the motor is lowered, and the rotational speed of the loading ring 4 is lowered to reduce the impact. Therefore, the loading speed becomes slow, the loading time becomes long, and there is still a possibility of tape damage.

Purpose of the invention The present invention solves the above-mentioned conventional problems.
The purpose is to provide a VTR device that shortens loading time and does not cause tape damage.

Structure of the Invention The present invention is a VTR device equipped with a winding means for winding a magnetic tape around a rotating drum, and a winding speed detection means for detecting the winding speed of the winding means. This makes it possible to freely control the winding speed and enable smooth loading.

DESCRIPTION OF THE EMBODIMENT FIG. 4 shows the first embodiment of the present invention.
FIG. 2 is a plan view of the VTR device. In Figure 3, 1
is a cassette, 2 is a magnetic tape, 3 is a rotating drum,
4 is a loading ring, 5 is a drive gear, 6 is an entry-side regulation post, 7 is an exit-side regulation post, 8 is an entry-side drawer post, 9 is a capstan, 10 is a pinch roller, 11 is a turn roller, 12 and 13 are The post, 18 is a motor, 19 is a frequency generator (FG), and 20 is a worm gear, which meshes with the drive gear 5.

The operation of the VTR apparatus of this embodiment configured as described above will be explained below.

At the start of loading, the magnetic tape 2 is at the 2' position, the drawer post 8 is at the 8' position, the pinch roller 10 is at the 10' position, and the turn roller 11 is at the 11' position, and voltage is applied to the motor 18. The worm gear 5 is rotated and rotational force is transmitted to the loading ring 4 via the drive gear 5. When the loading ring 4 rotates, the turn roller 11
It contacts and holds the magnetic tape 2 at position 2' and rotates around the rotating drum 3, thereby winding the magnetic tape 2 around the rotating drum 3. At the same time, the drawer post 8 is pulled out from the position 8' in conjunction with the loading ring 4 (not shown). An FG 19 is linked to the motor 18, and the rotational speed of the motor 18 can be detected by the FG 19.

FIG. 5 shows an example in which the rotational speed of the loading ring 4 is controlled by the output of the FG 19. Conventionally, since the rotation speed V was constant, the rise and fall were steep, and there was no control function, so the low speed 2
1, the loading ring 4 could only be rotated. However, according to the present invention, the straight line 22
By controlling the motor 18, the loading ring 4 is rotated, and the speed can be gradually increased at the rising edge and gradually lowered at the falling edge. Fluctuations can be avoided, and therefore the rotational speed of the loading ring 4 can be increased.
Loading time can be shortened.

As described above, according to the embodiment, by adding a rotation detection means to the motor 18, the rotation speed of the loading ring 4 can be detected, the rise and fall can be made gentle, and the speed during loading can be increased. This reduces loading time without causing tape damage.

FIG. 6 is a schematic diagram of a second embodiment of the invention.

The loading ring 4 has a tooth profile 26 that meshes with the drive gear 5. The magnet 24 and the hole IC 23 are arranged close to the tooth pattern 26 at positions separated by an integral multiple of the pitch of the tooth pattern 26, and the member 25 is close to the hole IC 23 and the magnet 24 so as to form a closed magnetic path. When the loading ring 4 rotates and the tooth pattern 26 approaches the hole IC 23 and the magnet 24, a closed magnetic path is formed with the loading ring 4, the hole IC 23, the member 26, and the magnet 24, and the hole IC 23 forms a closed magnetic path.
The magnetic flux passing through increases, and the output of the Hall IC increases. Furthermore, when the loading ring 4 moves half a pitch, the tooth pattern 26 of the loading ring 4
The trough directly faces the Hall IC 23 and the magnet 24 and is no longer a closed magnetic path, the magnetic flux passing through the Hall IC 23 decreases, and the output of the Hall IC 23 decreases. By reading this change, the rotational speed of the loading ring 4 can be detected.

As described above, according to this embodiment, by directly reading the tooth pattern of the loading ring 4, the detection unit 2
3, 24, and 25, the rotational speed of the loading ring 4 can be easily controlled, and the loading time and tape damage can be reduced.

In this embodiment, the Hall IC 23 is used, but the Hall IC 23 may be a coil. It goes without saying that the detection may be of a capacitance type or a light blocking type instead of a magnetic flux detection.

Effects of the Invention The VTR device of the present invention includes a winding means for winding a magnetic tape around a rotating drum, and a winding speed detection means for detecting the winding speed of the winding means, and detects the winding speed. This makes it possible to freely control the winding speed and enable smooth loading, which has great practical effects.

[Brief explanation of drawings]

Figure 1 is a schematic plan view of a conventional VTR device, Figure 2
3 is a front view of the same, FIG. 4 is a schematic plan view of an embodiment of the present invention, and FIG. 5 is a loading speed control characteristic diagram; FIG. 6 is a schematic plan view of another embodiment of the present invention. 1...cassette, 2...magnetic recording tape, 3...
...Rotating drum, 4...Loading ring, 19
...Frequency generator, 23...Hall IC, 2
4...Magnet, 25...Member, 26...Tooth pattern.

Claims (1)

[Scope of Claims] 1. A magnetic tape having a winding means for winding a magnetic tape around a rotating drum, and a winding speed detecting means for detecting a winding speed of the winding means, the winding speed being at least not low. A VTR device characterized by controlling speed. 2. The winding means is composed of a loading ring,
2. The VTR device according to claim 1, wherein the winding speed detecting means comprises means for reading the number of driving teeth formed on the loading ring.