JPH0222455B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a recording or reproducing apparatus for recording and reproducing signals, and more particularly to a recording or reproducing apparatus that can detect the progress state of a recording medium.

In non-endless tape recorders,
If the tape winds up on one reel,
The reels stop spinning. In this case, if the reel stand and its drive side are not separated in some way, the belt, idler, etc. may slip during the reel, deformation such as scraping of the rubber, etc., or troubles such as the tape breaking, etc., may occur.

To prevent this, an end stop function is required to stop the device when the tape is wound onto one of the reels and the end of the tape is reached.

Conventionally, as this type of end detection means, a means for detecting the stoppage of rotation of a reel hub within a cassette has been used. According to this method, it takes some time for the device to stop after the tape reaches its end, and during this time the leader tapes provided at both ends of the tape come into contact with the rotating magnetic head, causing the head to stop. It caused a blockage.

In order to eliminate such drawbacks, a method of optically detecting a transparent leader tape is generally used.

However, for optical detection, the light emitting side (or light receiving side) is inserted into a part of the cassette, and the light receiving side (or light receiving side) is positioned opposite to the light emitting side (light receiving side) with the tape in between. , it is necessary to locate the detection position at a location where the tape position does not change either in the loading state or in the state of being wound into a cassette.In a magnetic tape device using a small cassette, the cassette structure The structure was complicated in terms of space on the main body side, which hindered miniaturization.

SUMMARY OF THE INVENTION An object of the present invention is to provide a recording or reproducing apparatus that can detect a portion of a recording medium, such as the end of the recording medium, without taking up space on the apparatus main body and having a simple configuration.

1 and 2 show an embodiment in which the present invention is applied to end detection of a cassette type magnetic recording/reproducing apparatus (hereinafter referred to as VTR). In the figure, numeral 1 indicates a magnetic tape as a signal recording medium. Transparent leader tapes (portions to be detected) for end detection are provided at both ends of the magnetic tape 1. 2 is a take-up reel, 3 is a supply reel, 4 is a cassette for storing tape, 5
a, 5b are drawer guides (moving members) for pulling out the magnetic tape 1 from the cassette 4, 6 is a rotating cylinder provided with a rotating magnetic head, 7 is a light emitting part for end detection which is part of the detection member, 8a, Reference numeral 8b represents a light receiving section for termination detection; 9 is an OR circuit that outputs an output when light is input to the light receiving section 8a or 8b; and 10 is an amplifier circuit that amplifies the output of the OR circuit 9. Reference numeral 11 designates a known auto-stop mechanism that receives the output of the amplifier circuit 10, operates a solenoid, etc., enters a stop mode, and safely stops the apparatus.

FIG. 1 is a schematic plan view showing the recording and reproducing state of the VTR in this embodiment. In FIG. 1, the two-dot chain line indicates the tape path (first path) immediately after the cassette 4 is inserted into the VTR main body (so-called unloading state). In this state, the light emitting section 7 and the light receiving sections 8a and 8b for end detection are on the same side with respect to the magnetic tape 1. Next time you turn on recording or playback,
The magnetic tape 1 is pulled out by pull-out guides 5a and 5b, and moved to a path (second path) where it is wound around a rotating cylinder 6 by a little more than 180 degrees. During this loading, the light emitting section 7 is linked to a loading mechanism (not shown) that pulls out the magnetic tape 1.
The magnetic tape 1 moves to the space below the light emitting part 7.
After passing above the magnetic tape 1, the light receiving section 8
It moves to a predetermined position in the tape movement space facing tapes a and 8b, and is fixed at that position. With this configuration, the light emitted from the light emitting section 7 is blocked by the magnetic tape 1 in the portion that does not reach either end of the tape, and is directed to the light receiving section 8.
a, 8b is not reached, there is no output from the OR circuit 9, and the auto-stop mechanism 11 does not operate. Next, when the leader tape is wound onto the take-up reel 2 during recording, normal playback, or fast-forward playback, a transparent leader tape appears from the supply reel 3, and if it passes through the optical path indicated by arrow 7a in FIG. When the light reaches the light receiving section 8a, the OR circuit 9 outputs an output, the auto-stop mechanism 11 is activated, and the apparatus is safely stopped before the transparent leader tape reaches the rotating cylinder 6. For rewind playback,
The magnetic tape 1 is wound onto the supply reel 3 side, a transparent leader tape appears from the take-up reel 2 side, and by passing through the optical path, light reaches the light receiving section 8b, the OR circuit 9 outputs an output, and an auto-stop is performed. Mechanism 11 is activated.

FIG. 2 is a schematic plan view showing the fast forward and rewind states of the VTR of this embodiment when a cassette is attached. When cassette 4 is inserted into the VTR body,
A loading completion switch (not shown) indicating completion of loading the cassette is automatically turned on and loading of the magnetic tape 1 is started. As shown in FIG. 2, the drawer guides 5a and 5b have a light emitting part 7 sandwiching the magnetic tape 1 and facing the light receiving parts 8a and 8b, and the drawer guide 5
When a and 5b reach a position where the optical path is not obstructed and the magnetic tape 1 does not come into contact with the rotating cylinder, loading is stopped and the tape waits in this state until the next mode switch is turned on (this state is hereinafter referred to as half-loading). ). When the switch for recording or playback is turned on, the drawer guides 5a and 5b
further loads, resulting in the state shown in FIG.

When a switch instructing fast forwarding or rewinding is turned on, fast forwarding or rewinding is performed in the state shown in FIG.

In the case of fast forwarding, the magnetic tape 1 is placed on the take-up reel 2
When the transparent leader tape appears from the supply reel 3, light reaches the light receiving section 8b, the OR circuit 9 outputs an output, and the auto-stop mechanism 11
is activated. In the case of rewinding, contrary to the case of fast forwarding, when the transparent leader tape appears from the take-up reel 2, light reaches the light receiving section 8a and the auto-stop mechanism 11 is activated.

3 to 6 are diagrams showing embodiments of a light emitting device including the light emitting section 7. FIG.

12 is a tube for fixing the light emitting part 7; 13 is a tube 12;
14 is a shaft fixed to the support 13 and rotatably supports the cylinder 12; 15 is a spring serving as a biasing member for regulating the rotation of the cylinder 12; 16 is a spring 15; 17 is a guide groove for pulling out the magnetic tape 1;
8 is a base plate, 19 is a screw that fixes the support base 13 to the base plate 18, 20 is a vertical post that guides the running of the magnetic tape 1, 21 is a tilted post, 22 is a tilted post fixing base that fixes the tilted post 21, and 23 is a tilted post fixing base for fixing the tilted post 21. An upper guide 24 moves the inclined post fixing base 22 along the guide groove 17, and 24 is a lower guide.

The light emitting section 7 for detecting the end of the magnetic tape 1 is connected to the tube 12.
This cylinder 12 is rotatably supported by a shaft 14 fixed to a support base 13. Support stand 1
3 has a surface for regulating the position of the tube 12;
is biased by a spring 15 and is normally fixed at the position shown in FIG. Loading starts, and the vertical post 20 and the inclined post 21 are moved along the guide groove 17.
When it moves, it comes into contact with a part of the cylinder 12 of the inclined post fixing base 22. Cylinder 1 of inclined post fixing base 22
2 is a cam surface that applies force in the direction in which the cylinder 12 can rotate, so as the tilted post fixing base 22 moves, the cylinder 12 moves toward the shaft 14.
Tilt around the center. This usually results in magnetic tape 1
The light emitting unit 7, which is located at a position that blocks the loading of the magnetic tape 1, moves to the lower part of the magnetic tape 1 and escapes out of the tape movement space. When the tilted post fixing base 22 further moves, the cylinder 12 rises due to the force of the biased spring 15, sandwiching the magnetic tape 1, and the light receiving part 8a,
Opposite 8b.

In the embodiment of the present invention described above, the positional relationship between the light emitting section 7 and the light receiving sections 8a and 8b may be reversed. Furthermore, during fast forwarding and rewinding, there is also a method in which the auto-stop mechanism 11 is configured to operate when the reel stand stops rotating, and half loading is not performed.

FIG. 7 is a diagram showing the structure of another embodiment of the light emitting device. The inclined line portion 25 is made of an elastic material (biasing member) such as rubber or a spring, and in this case, the light emitting device is usually fixed perpendicularly to the base plate 18.
At the start of loading, a part of the tilted post fixing base 22 shown in FIG. 6 applies force to the tilted line portion made of an elastic material, causing the light emitting device to tilt and escape out of the tape movement space. It is.

Although the embodiment shown above is used for detecting the end of the recording medium, it is also possible to provide a detection tape at any location on the magnetic tape 1.

Further, after detection, the automatic stop mechanism is not limited to operating, but other operations such as switching the operation mode may be performed.

As explained above, according to the present invention, although it has an extremely simple configuration, it has a structure that does not require any trouble that would normally occur, so it has a long life, does not take up space, and can detect a part of a tape-shaped recording medium. A recording or reproducing device can be obtained.

[Brief explanation of drawings]

FIG. 1 is a plan view showing the state of a VTR as an embodiment of the present invention in a recording or reproducing state, and FIG. 2 is a plan view showing the state of the VTR shown in FIG. 1 in a fast forward or rewind state. 3 is a plan view of the light emitting section, FIG. 4 is a front view of the light emitting section, FIG. 5 is a plan view showing the tilted state of the light emitting section, FIG. 6 is a front view showing the tilted state of the light emitting section, and FIG. The figure is a front view showing another embodiment of the light emitting section. In the figure, 1 is a magnetic tape, 4 is a cassette,
5a, 5b are drawer guides, 7 is a light emitting part, 8a, 8
b is a light receiving section, 9 is an OR circuit, 10 is an amplifier circuit, 1
1 indicates an auto-stop mechanism.

Claims (1)

[Claims] 1 A device for recording signals on or reproducing signals from a tape-shaped recording medium housed in a cassette and having a portion to be detected in a part thereof, which has a rotating part for recording or reproducing on the outer circumferential surface. a cylinder having a head; a movable member for setting the path of the medium to at least a first path in the cassette and a second path wrapped around the outer peripheral surface of the cylinder; a detection member for detecting; and a biasing member that biases at least a portion of the detection member to be located at a predetermined position in a movement space of the medium from the first path to the second path. A recording or reproducing apparatus comprising: avoidance means for resisting the bias and avoiding the detection member out of the movement space only during a predetermined period while the medium is being moved by the movement member.