JPH0540980A - Tape trailing end detector - Google Patents

Abstract

PURPOSE:To detect the tape trailing ends of both cassettes in a tape recorder capable of using both a digital compact cassette and an analog compact cassette. CONSTITUTION:The projector 5 and the light receiver 6 of an optical sensor are buried in a columnar body 4 inserted into the reference hold 12 of the internal one of two reference holes provided on a cassette main body, in the case of a DCC, a light emitted from the projector 5 is reflected by a light reflection layer formed on the surface in the vicinity of the connecting part of a reader tape part of the connecting part between the reader tape and a magnetic tape, a reflected light is received by the light receiver 6, the operation of the optical sensor is activated and the trailing end of a tape 3 is detected. In the case of an ACC, since the light is transmitted through the reader tape part, a light emitted from the projector 5 is transmitted through the reader tape part, reflected by a reflector 7, the reflected light is transmitted through the reader tape again and received by the receiver 6, the optical sensor is activated to detect the trailing end of the tape 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tape end detecting a tape end portion of both a digital compact cassette and an analog compact cassette in a tape recorder which can use a digital compact cassette and an analog compact cassette. Regarding a detection device.

[0002]

2. Description of the Related Art In a conventional analog compact cassette (hereinafter referred to as ACC), a magnetic tape end is detected and a quick reversal is performed. Therefore, a light-transmitting leader tape portion at the magnetic tape end is optically detected. The method was adopted.

FIG. 5 shows an example of a conventional tape end detecting device for optically detecting the leader tape portion at the end of the magnetic tape. In FIG. 5, 3 is a tape, 5 is a light projecting portion of an optical sensor, 6 is a light receiving portion thereof, 8 is a head block, 9 is a sillad base for moving the head block 8 back and forth,
Reference numeral 10 is a basic base, 11 is an ACC body, 12 is a reference hole provided in the ACC body 11, 14 is a small window provided in the ACC body 11, 16 is a columnar body, 17 is a reflecting surface provided on the columnar body 16. Is.

In the conventional tape end detecting device shown in FIG. 5, while the magnetic tape portion of the tape 3 is passing through the small window 14 provided in the ACC 11, the light emitted from the projector 5 is a magnetic tape. It does not reach the reflection surface 17 provided on the columnar body 16 because it is blocked by. Further, the reflectance of the magnetic tape portion is low, the amount of reflected light is small, and the output of the light receiver 6 does not exceed the threshold value to operate the optical sensor.
However, when the tape 3 passing through the position of the small window 14 approaches the end and the leader tape portion that transmits light reaches the position of the small window 14, the light emitted from the projector 5 emits light as shown in FIG. To the tape 3 again.
And a part of the reflected light is incident on the light receiver 6. Since the light transmittance of the leader tape portion is sufficiently high, the amount of the reflected light incident on the light receiver 6 is sufficiently large that the output of the light receiver 6 exceeds the threshold value, the optical sensor operates, and the tape 3 ends. And the change from the magnetic tape portion to the leader tape portion is detected. The operation signal of this optical sensor can be used to control the stopping of the tape 3 and quick reflection.

[0005]

However, in the above-mentioned tape end detecting device, the small window 14 provided in the ACC main body 11 is not provided in the digital compact cassette (hereinafter referred to as DCC). There was a problem that the end of the tape could not be detected.

The structure of the DCC will be described below. FIG. 2 shows a state where the DCC is taken out from the recorder. 2A is a plan view, FIG. 2B is a front view, and FIG.
(C) shows a bottom view, 1 is a DCC body, 2 is a shutter, and the shutter always covers the tape and the main part. FIG. 3 shows a state of the DCC when the DCC is mounted on a recorder and is actually used. 3A shows a front view and FIG. 3B shows a bottom view. When the DCC is mounted on the tape recorder, the shutter 2 moves leftward as shown in FIGS. 3A and 3B, and the tape 3, the reference hole 12 and the reel hub 13 are exposed.

The structure of the ACC will be described for comparison. The appearance of the ACC is shown in FIG. FIG. 4A is a front view of the ACC and FIG. 4B is a bottom view. 4A and 4B, 3 is an exposed tape, 11 is an ACC main body, 12 is a reference hole, 13 is a reel hub, 14 is a small window, 1
Reference numeral 5 is a tape see-through window.

As is clear from a comparison between FIG. 3A and FIG. 4A, the DCC shown in FIG.
The small window 14 shown in ACC is not provided. Therefore, as described above, in the conventional tape end detecting device,
Tape end detection in DCC is impossible.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above problems and enable both the DCC and ACC tape end detection with the same tape recorder and the same tape end detection device.

[0010]

In order to achieve the above object, according to the present invention, the DCC is inserted into one of the two reference holes provided at a position common to the ACC and the DCC. The light emitting portion and the light receiving portion of the optical sensor are embedded in the columnar body, and the light reflecting layer formed on the surface near the leader tape portion of the DCC or the connecting portion of the leader tape and the magnetic tape causes the light emission of the optical sensor. The light emitted from the light-reflecting portion is reflected and the light reflected from the light-reflecting layer is received by the light-receiving portion. For ACC, in addition to the above-mentioned means, the ACC outside the small window portion of the ACC A reflector is provided at the position, light emitted from the light projecting portion of the optical sensor is reflected by the reflector, and reflected light reflected by the reflector is received by the light receiving portion.

[0011]

According to the above-mentioned means for DCC, the light emitted from the light projecting portion of the optical sensor embedded in the columnar body is reflected on the surface near the leader tape portion of the DCC or the connecting portion between the leader tape and the magnetic tape. By the light reflection layer formed, since the reflected light is received by the light receiving portion, due to the difference between the reflectance of the light reflecting layer and the reflectance of the magnetic tape portion,
The leader tape portion of the DCC, that is, the tape end portion can be detected.

According to the means for ACC, only the leader tape portion transmits light, the magnetic tape portion other than the leader tape does not transmit light, and the magnetic tape portion has a low reflectance, so that the ACC is small. The reflected light from the reflector provided at the position facing the window arrives at the light receiving portion only at the light-transmitting leader tape portion. Therefore, by receiving the reflected light from the reflector, the tape end portion in the ACC. Can be detected.

[0013]

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

First, FIG. 1A shows an embodiment in which the tape end of the DCC is detected by the tape end detecting device of the present invention. In FIG. 1A, the same parts as those in FIG. 5 showing the conventional example are denoted by the same reference numerals, and therefore the description thereof will be omitted and only different points will be described. In FIG. 1A, 1 is a DCC main body, 2 is a DCC shutter, 4 is a columnar body, and a projector 5 and a light receiver 6 of an optical sensor are embedded in the columnar body 4. Reference numeral 7 is a reflector used to detect the end of the tape when the ACC is attached to this tape recorder.

In such a structure, even if the magnetic tape portion of the DCC tape 3 is at the positions of the projector 5 and the light receiver 6 of the optical sensor, the magnetic tape portion of the magnetic tape of the tape 3 has a low reflectance. The light emitted from the light projector 5 is not significantly reflected by the tape 3, the amount of reflected light incident on the light receiver is small, and the optical sensor does not operate. However, when the leader tape portion comes to the positions of the light projector 5 and the light receiver 6, the light reflection layer formed on the surface of the leader tape causes
The light emitted from the light projector 5 is reflected and incident on the light receiver 6, and the optical sensor operates to detect the leader tape portion, that is, the tape end.

The light reflecting layer formed on the surface of the leader tape portion in the DCC described in the above description is, for example, a light reflecting layer having a high reflectance characteristic formed by aluminum vapor deposition on the leader tape surface. It is a thing. Alternatively, a splicing tape for connecting a magnetic tape portion and a leader tape equivalent to a conventional one may be provided with a high reflectance characteristic by a process such as aluminum vapor deposition.

Next, FIG. 1B shows the case where the ACC is mounted on the tape recorder having the same structure as that of FIG.

In FIG. 1 (b), the same parts as those in FIG. 1 (a) are designated by the same reference numerals, and therefore, duplicated description is omitted and it is necessary to note that the parts are different from those in FIG. 1 (a). There will be explained a part where there is.

In FIG. 1B, 14 is a small window provided in the ACC main body 11 as described in FIG. 4A.
The reflector 7 is provided in front of the small window 14 on the side where the columnar body 4 is provided. In the configuration shown in FIG. 1 (b),
When the magnetic tape portion of the tape 3 is at the position of the small window 14, that is, at the position of the projector 5 and the light receiver 6 of the optical sensor, the magnetic tape portion has no light transmission and a low reflectance, so that the light receiver The amount of reflected light incident on 6 is small,
The optical sensor does not work. However, when the leader tape portion comes to the position of the small window 14, since the leader tape portion has high light transmittance, the light emitted from the projector 5 passes through the leader tape portion and is reflected by the reflector 7. The reflected light again passes through the leader tape portion and enters the light receiver 6. In this case, the amount of light incident on the light receiver 6 is sufficiently large so that the optical sensor operates to detect the leader tape portion, that is, the tape end.

Although the reflector 7 in FIGS. 1 (a) and 1 (b) is provided independently, the head block 8 is extended to a predetermined position and its surface is mirror-finished so that the reflector 7 is formed.
May be used instead of.

[0021]

As is apparent from the above description, according to the present invention, in a tape recorder capable of using both a digital compact cassette and an analog compact cassette, a digital recorder having a completely identical compact structure can be used. It is possible to detect the tape end of both the compact cassette and the analog compact cassette, which can greatly contribute to the miniaturization of the tape recorder itself.

[Brief description of drawings]

FIG. 1 (a) is a cross-sectional view of a main part when a digital cassette tape is mounted in an embodiment of a tape end detection device of the present invention, and (b) is a case where an analog cassette tape is mounted in the same device. Sectional view of the same section

2A is a plan view of the digital compact cassette, FIG. 2B is a front view of the same cassette, and FIG. 2C is a bottom view of the same cassette.

FIG. 3A is a front view of the same cassette with a shutter opened, and FIG. 3B is a bottom view of the same cassette in the same state.

FIG. 4A is a front view of the analog compact cassette, and FIG. 4B is a plan view and bottom view of the same cassette.

FIG. 5 is a sectional view of a main part of a conventional tape end detection device.

[Explanation of symbols]

 3 Tape (leader tape part) 4 Columnar body 5 Emitter 6 Light receiver 7 Reflector 12 Reference hole 14 Small window

Claims (2)

[Claims] 1. In a tape recorder, a light projecting portion and a light receiving portion of an optical sensor are embedded in a columnar body which is inserted into one of the reference holes provided at two positions of a cassette main body, and a digital unit is provided. A light reflection layer formed on the surface of the leader tape part of the compact cassette or near the connection part of the leader tape and the magnetic tape reflects the light emitted from the light emitting part of the optical sensor, and the reflected light is received by the light receiving part. Tape end detection device that receives light. 2. In a tape recorder, a light projecting portion and a light receiving portion of an optical sensor are embedded in a columnar body inserted into one reference hole of two reference holes provided in a cassette body, and a small window of the cassette is provided. A light is emitted from the projector of the optical sensor, and the light is emitted from the projector of the optical sensor. A tape end detection device that detects a transparent leader tape section.