JPH08273236A - Tape slack detector of tape recorder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent damage to a drive system, by providing a light-emitting element and a light-receiving element at the final position of a tape after loading, and instantaneously stopping driving of a deck mechanism when any sag of the tape is detected. SOLUTION: In the case where tape sag is generated, since a tape 15 is located between a light-emitting element 30 and a light-receiving element 31, a light emitted from the light-emitting element 30 is interrupted by the tape 15 and thus the light-receiving element 31 is prevented from receiving the light. When the light-receiving element 31 does not receive the light even though a tape loading mechanism is actuated, a microcomputer 50 as a halting device recognizes an abnormal operating state based on a signal from the light- receiving element 31 and sends a stop signal to a deck drive unit to prohibit a cassette unloading mechanism from proceeding, thereby automatically stopping driving of the mechanism.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tape slack detecting device for a tape recorder, and more particularly to a tape slack detecting device for detecting tape slack that is not accommodated in a cassette when unloading a tape. The present invention relates to a tape slack detecting device for a tape recorder capable of stopping driving of a deck mechanism.

[0002]

2. Description of the Related Art An ordinary video cassette tape recorder (hereinafter referred to as "VCR"), which is well known in the prior art, is provided with a cassette front loading mechanism and a tape loading mechanism. When the videotape cassette that stores the videotape is inserted horizontally into the cassette insertion part formed on the front of the VCR, the front loading mechanism uses the cassette holder for storing the cassette, and the cassette is placed inside the recorder together with the cassette holder. Pull in. After that, the cassette is lowered to the specified cassette loading position, and at the same time, the cover covering the tape is opened. afterwards,
The tape guide member of the tape loading mechanism is inserted into the cassette and brought into contact with the inner surface of the tape.

Next, the tape loading mechanism operates. In this tape loading mechanism,
The tape guide member pulls out the tape from the cassette arranged at the cassette loading position and acts on the tape so as to come into contact with about half the circumference of the head drum. According to the tape loading mechanism, once the tape is loaded along the tape feed path, recording, playback, still screen,
One of various operation modes of slow reproduction, fast-forward reproduction, fast-rewind reproduction, fast-forward, and fast-rewind is selected and executed. When the eject key is operated to eject the tape after executing the predetermined operation mode, the tape loading mechanism pulls the tape into the cassette by the operation opposite to the tape loading operation, and at the same time, the front loading mechanism moves the cassette to the cassette. The cassette is taken out from the loading position to the initial cassette insertion position.

FIG. 1 schematically shows an internal structure of a conventional tape recorder in which a tape is loaded at a cassette loading position according to the mechanism described above. The tape loading mechanism will be described in more detail below with reference to FIG.

At the upper part of the deck, a tape loading system for guiding the tape 15 from the cassette 16 is provided for guiding the tape to the running system. The tape loading system includes a pair of first and second loading rails 20a, 2 formed on the main plate 19.
0b and the first motor driven by a loading motor
And a pair of first and second pole bases 21a and 21b that can move along the second loading rails 20a and 20b. The first and second pole bases 21a and 21b include the first and second guide rollers 22a and 22b and the first and second inclined poles 23a and 2b.
3b, respectively, to support and guide the tape 15 during tape loading.

After the loading operation is completed by the tape loading system, the magnetic tape 15 for reproducing or recording the video signal and / or the audio signal is attached to the magnetic erasing head 11, the head drum 12, the audio / control head 13, the capstan shaft 14. The video signal and / or the audio signal is reproduced or recorded at the same time as the tape is run along the tape running system formed by the above. The magnetic tape 15 is wrapped around a pair of wheels provided in the cassette 16. The cassette 16
When the tape is mounted on the deck of the tape recorder, the pair of wheels are mounted on the supply reel 17 and the take-up reel 18, which are mounted on the main plate 19, respectively. As a result, the tape 15 is supplied to the supply reel 17 and the take-up reel 18. According to the direction of rotation of the wheel, it is wound around the other wheel, away from one wheel.

The tape recorder shown in FIG. 1 is in a state in which the tape is completely loaded by the tape loading system, that is, in which an audio or video signal can be recorded or reproduced.

When the tape is unloaded to take out the cassette after performing various functions under the above-mentioned loading conditions, the first and second pole bases 21a and 21b are opposite to the first and second pole bases 21a and 21b. The tape 15 that has been moved along the second loading rails 20a and 20b and returned to the original position and then pulled out is stored in the cassette 16 again by driving the reels 17 and 18. At this time, the tape 15 may not be stored in the cassette 16 and only the first and second pole bases 21a and 21b may move due to a defect in the deck mechanism or other factors.

2A and 2B show a comparison of the states of the tape during the cassette unloading operation. FIG. 2A shows the first and second pole bases 21.
a and 21b are the first and second loading rails 20.
Return to the original position along a, 20b, and tape 15
Of the first and second pole bases 21a, 21b are shown in FIG. 2B.
21b shows a state in which the tape 15 is returned to the original position, but the tape 15 is left in the loading position without being stored in the cassette 16.

As shown in FIG. 2B, even if the first and second pole bases 21a and 21b are returned to their original positions, the tape 15 is not stored in the cassette 16 but left in the loading position. In some cases, tape slack will occur. If the cassette is taken out without knowing the occurrence of slack in the tape, the tape may be caught in the peripheral parts in the recorder, damaged, contaminated by the grease coating the peripheral parts, or cut, which may be harmful. . Moreover, the tape drive system becomes unusable if the grease-contaminated tape comes into contact with the tape drive system. In addition, operating the cassette unloading mechanism when there is slack in the tape can cause the tape to be pinched between the cover and the chassis at the same time as the cover closes.

A great deal of research has been done on the prevention of tape slack or the treatment when it occurs. For example, U.S. Pat. No. 5,086,359 granted to Tsuchiya et al. Discloses a capstan that not only drives a tape drive reel base but also a cassette front loading mechanism. An apparatus for preventing sagging of a video tape recorder having a motor is disclosed.

Further, in US Pat. No. 4,679,109 granted to Okamura et al., In order to prevent the tape from being pinched when unloading a tape having slack, An apparatus for improving the end shape of a drive rib of a tape reel is described. However, the device needs to be applicable when the front loading mechanism and the tape drive mechanism are driven separately by the respective motors, and that the tape slack can be easily detected even with a simple device.

[0013]

SUMMARY OF THE INVENTION The present invention is to solve the above-mentioned problems. Therefore, it is an object of the present invention to easily detect the occurrence of slack in the tape where the tape is not stored in the cassette when performing the unloading operation of the tape, and to detect the slack state of the deck mechanism. It is an object of the present invention to provide a tape slack detecting device for a tape recorder, which can stop the driving and consequently prevent the damage and the contamination of the tape caused by the continuous driving of the deck mechanism under the slack condition. .

[0014]

To achieve the above object, the present invention moves along a loading plate by a driving motor for loading and unloading a main plate having a loading rail and a tape. Provided is a tape sag detecting device for a tape recorder having a pole base. The light emitting element is attached to one of the final positions of the tape after loading so as to emit light, and the light receiving element receives the light emitted from the light emitting element. Therefore, the light receiving element is centered on the tape at the final position of the tape after loading. It is attached so as to face the light emitting element. In addition, the stop unit stops the deck mechanism when the light received from the light receiving element is less than or equal to a predetermined value when unloading the tape.

Preferably, the light emitted from the light emitting element is allowed to pass through the widthwise central portion of the loaded tape at the final position of the tape after loading. More preferably, the light emitting element and the light receiving element are mounted on a substrate below the main plate. Further, the main plate includes a first reflecting unit for reflecting the light emitted from the light emitting element toward the tape and a second reflecting unit for reflecting the light passing through the first reflecting unit toward the light receiving element. To be installed. Here, it is preferable to use prisms as the first and second reflecting means.

According to the tape slack detecting device of the present invention, the occurrence of slack during unloading of the tape can be detected in the initial state. Therefore, once the slack state is detected, the drive of the deck mechanism can be immediately stopped. It is possible to prevent damage and contamination of the tape.

[0017]

DETAILED DESCRIPTION OF THE INVENTION The present invention will be described below in detail with reference to the accompanying drawings. In FIG. 3, the first pole base 21a is moved to the end of the loading rail at the cassette loading position of the tape recorder provided with the tape slack detecting device according to one embodiment of the present invention, so that the tape 1
5 shows a magnified view of the essential part of the final position of the tape after 5 is completely loaded. In this drawing, only one part of the final positions of the pair of tapes arranged opposite to each other is shown.

The tape 15 is a drive motor (not shown).
When the first guide roller 22a and the first inclined pole 23a provided on the upper portion of the first pole base 21a that moves along the loading rail formed on the main plate by the driving force supplied from Simultaneously supported and guided. Here, the main plate 19
Has a pair of loading holes having an arc shape. The loading rail is formed along the peripheral edge of the loading hole. The light emitting element 30 and the light receiving element 31 are arranged to face each other on both sides of the first guide roller 22a. A pair of the light emitting element 30 and the light receiving element 31 arranged at the final position of the tape after loading are provided to detect the presence of the tape when the unloading operation of the tape 15 is performed.

The loading and unloading of the tape is performed by a tape loading system. In this tape loading system, the first and second pole bases 21a and 21b are formed on the main plate 19 to form the first and second pole bases. Loading rails 20a, 2
Move along 0b and guide. When carrying out the loading operation of the tape 15, the first and second guide rollers 22a and 22b and the first and second inclined poles 23a and 23b for supporting and guiding the tape 15 are attached to the first and second poles. It is attached to the bases 21a and 21b. In other words, the front loading mechanism inserts the cassette into the tape recorder, lowers it to the final position of the cassette after loading, opens the tape cover, and forms it on the first and second pole bases 21a and 21b, respectively. The first and second guide rollers 22a, 2
2b and the first and second inclined poles 23a, 23b,
It is brought into contact with the inner surface of the tape 15. Then, the first and second
The pole bases 21a, 21b of the tape move along the first and second loading rails 20a, 20b, and the tape 15 moves from the cassette 16 to the first and second guide rollers 22a, 22b and the first and second guide rollers 22a, 22b. Inclined pole 23a,
The tape loading is completed when the pole base stops by being pulled out and supported on both sides of the head drum 12 by 23b.

As shown in FIG. 3, the light emitting element 30 and the light receiving element 31 of the tape slack detecting device according to the present invention are arranged at the final position after the tape 15 is loaded. These are arranged on opposite sides of the first guide roller 22a where the first pole base 21a is at the final position after loading. Therefore, after the tape loading, the tape is positioned between the light emitting element 30 and the light receiving element 31, so that the light from the light emitting element 30 is blocked by the tape 15 and the light receiving element 31 cannot receive the light. However,
After the tape is unloaded, the tape is not located between the light emitting element 30 and the light receiving element 31, so the light emitting element 3
The light from 0 is not blocked and is received by the light receiving element 31.

If the light receiving element 31 does not receive light after unloading the tape, this means that the tape is not wound into the cassette and remains at the tape loading position, resulting in tape slack. Means that. Therefore, the tape slack can be detected by sensing whether or not the light is received by the light receiving element.

4A and 4B show an operating state of the slack detecting apparatus according to the present invention. FIG. 4A corresponds to a state where the tape slack does not occur after the tape unloading, and FIG. 4B shows the tape after the tape unloading. This corresponds to the state when sagging occurs. First, a normal state will be described with reference to FIG. 4A. The tape remains unloaded according to the normal tape unloading mechanism. When the first pole base 21a returns to the original position along the loading rail, the first guide roller 22a formed on the first pole base 21a.
And the tape 1 supported by the first inclined pole 23a
5 is drawn into the cassette.

At this time, the light emitting element 30 and the light receiving element 31
There is no light blocking element between them, and the light emitted from the light emitting element 30 is received by the light receiving element 31. Therefore, the microcomputer senses this state as a normal unloading operation and operates the cassette unloading mechanism having the deck mechanism to insert the tape into the cassette to be taken out instead of the outside.

Next, referring to FIG. 4B, a state in which the slack of the tape is implied will be described. According to a general tape unloading mechanism, the first pole base 21
a, the first guide roller 22a, and the first inclined pole 23a
Is moving to return to its original position, but tape 1
5 is due to factors such as defects in the deck mechanism,
Left in the tape loading position. That is, tape slack has occurred. In this case, since the tape 15 is located between the light emitting element 30 and the light receiving element 31, the light emitted from the light emitting element 30 is blocked by the tape 15, thereby preventing the light receiving element 31 from receiving light. To do. If the light receiving element 31 does not receive light even if the tape unloading mechanism is activated,
The microcomputer 50 as a stop device recognizes an abnormal operating state based on a signal from the light receiving element 30,
A stop signal is sent to the deck drive unit to inhibit the cassette unloading mechanism from proceeding and automatically stop the drive of the mechanism.

At this time, even if the light from the light emitting element 30 is blocked by the tape 15 due to the occurrence of slack in the tape, the light receiving element 31 receives a slight amount of light generated as a result of the diffraction phenomenon of light. It is possible. Therefore, it should be recognized that the light is blocked even when it receives light below a predetermined value. In the above-described embodiment, when the head drum 12 is the center, the tape slack detecting device is provided only at one of a pair of final positions after loading, which are opposed to each other. May be provided in the other location,
It can be provided in both final positions after loading if desired.

FIG. 5 shows an example in which the slack detecting device according to one embodiment of the present invention is arranged in a tape recorder. The tape 15 is arranged on the main plate 19, and the light emitting element 30 and the light receiving element 31 are arranged on the substrate 32 below the main plate 19. The first prism 4 for reflecting the light emitted from the light emitting element 30 to the light receiving element 31.
0 and a second prism 41 for reflecting the light reflected from the light emitting element 30 to the light receiving element 31 are arranged above the main plate 19. Microcomputer 50
Is connected to the light receiving element 31, and the drive unit 60 of the deck mechanism is connected to the microcomputer 50.

The first prism 40 is disposed above the light emitting element 30 and, when the tape is completely loaded, the light emitting element 3
The first prism 40 is provided in order to function by reflecting the light from 0 toward the position where the tape is arranged. At this time, it is desirable that the first prism 40 is arranged so that the light reflected from the first prism 40 acts so as to pass through the central portion of the tape 15.

Since the second prism 41 is arranged above the light receiving element 31, the light reflected from the first prism 40 is received and reflected by the light receiving element 31 in the lower part of the second prism 41, so that the second prism 41 functions. The second prism 41 is provided.
As a result, the light emitted from the light emitting element 30 can be received by the light receiving element 31 by the first prism 40 and the second prism 41. As an alternative to the method described above, the tape sag detection device according to the present invention can be attached by various methods.

On the other hand, when tape slack occurs during tape unloading, a display unit 70 for additionally performing a predetermined display operation can be additionally provided in accordance with the abnormal operation state recognized by the microcomputer 50. . More preferably, a light emitting diode attached to a predetermined portion of the front control panel of the tape recorder is formed on the display unit 70. Otherwise, a voice guidance message storage device for storing predetermined voice guidance message data and a message reproducing device for reproducing and outputting the voice guidance message data stored in the voice guidance message storage device can be provided. . When the display unit 70 is provided, the operator can immediately recognize the occurrence of tape slack from the outside of the tape recorder. As a result of this, the condition of the tape recorder is well recognized.

Although the present invention has been described in detail with reference to the above embodiments, the present invention is not limited to this, and modifications and improvements can be made by those skilled in the art within the scope of the claims. is there.

[0031]

As described above, the tape slack detecting device according to the present invention detects the tape slack when performing the tape unloading operation by providing the light emitting element and the light receiving element at the final position of the tape after loading. Enables this to instantly stop the drive of the deck mechanism when a tape slack is detected. Therefore, it is possible to prevent damage to the tape and further damage to the drive system.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing an internal structure of a conventional video tape recorder when a tape is loaded at a cassette loading position.

FIG. 2A shows a conventional video tape recorder,
FIG. 6 is a diagram showing a tape completely stored in the cassette when the cassette is unloaded, and B is a diagram showing a tape not stored in the cassette.

FIG. 3 is an enlarged view of a main part of a tape recorder provided with a slack detecting device according to an embodiment of the present invention in which a tape is completely loaded at a cassette loading position.

FIG. 4 is a diagram showing an operating state of the slack detecting device according to the present invention, where A is a case where no slack is generated and B is a case where slack is generated.

FIG. 5 is a schematic view showing an example in which a slack detecting device according to an embodiment of the present invention is attached to a tape recorder.

[Explanation of symbols]

 11 magnetic erasing head 12 head drum 13 audio / control head 14 capstan shaft 15 tape 16 cassette 17 supply reel 18 take-up reel 19 main plate 20a, 20b loading rail 21a, 21b pole base 22a, 22b guide roller 23a, 23b inclined pole 30 light emitting element 31 light receiving element 32 substrate 40, 41 prism 50 microcomputer 60 driving unit of deck mechanism 70 display unit

Claims (7)

[Claims] 1. A main plate having a loading rail, a pole base which moves along the loading rail by driving a driving motor for loading and unloading the tape, and a tape mounted at one of the final positions of the tape after loading. In addition, a light emitting element for emitting light, a light receiving element attached to face the light emitting element around the tape at the final position of the tape after loading, for receiving the light emitted from the light emitting element, and the tape A tape slack detecting device for a tape recorder, which has a stopping means for stopping a deck mechanism when the light received by a light receiving element is below a predetermined value during unloading. 2. The tape sag detecting device of the tape recorder according to claim 1, wherein the light emitted from the light emitting element passes through a central portion in the width direction of the tape loaded at the final position of the tape after loading. 3. The light emitting element and the light receiving element are mounted on a substrate below the main plate, and the main plate further includes a first reflection for reflecting light from the light emitting element in a tape direction. 2. The tape slack detecting device for a tape recorder according to claim 1, further comprising: a means and a second reflecting means for receiving the light having passed through the first reflecting means and reflecting the received light toward the light receiving element. . 4. The tape slack detecting device for a tape recorder according to claim 3, wherein the first and second reflecting means have prisms. 5. The tape sag detecting device for a tape recorder according to claim 1, wherein the stopping means is a microcomputer. 6. A display unit is provided at a predetermined portion of a front control panel of the tape recorder for performing a predetermined display operation when the light received by the light receiving element is below a predetermined value during unloading of the tape. The tape sag detecting device of the tape recorder according to claim 1. 7. The tape slack detecting device for a tape recorder according to claim 6, wherein the display section has a light emitting diode.