JPH09251756A - Tape cassette - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately discriminate the kind of a tape housed in a cassette main body. SOLUTION: Light H1 emitted to a cassette main body of this cassette from a sensor 1 is projected via a prism 5 provided therein to tape end detecting patterns 9 and 10 of light untransmissibility provided on a splicing tape 8 for splicing a magnetic tape 6 with a leader tape 7, and the presence of its return light H2 is received by this tape end sensor 1 so as to discriminate the kind of the tape. In this constitution, light leakage preventing means 19 and 20 are provided on both side surfaces of the prism 5 along the traveling direction of the emitted light H1 .

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tape cassette, and more particularly to a tape cassette capable of identifying the type of tape stored in a cassette body.

[0002]

2. Description of the Related Art A tape cassette used in a digital audio tape recorder (DAT) is usually used for recording / reproducing music information, but it is also used for recording / reproducing data with the same external configuration. . A tape cassette (hereinafter referred to as a data cassette) used for recording / reproducing such data has a magnetic field with less error than that of a magnetic tape used for recording / reproducing music information in order to enhance the reliability of the recorded data. Tape is used.

As described above, since it is necessary to use a more reliable magnetic tape for the data cassette, a tape cassette (hereinafter, referred to as "recording / reproducing" of music information) is used.
It is called a DAT cassette. ) And the data cassette must be used separately. That is, the DAT cassette is used as a cassette dedicated to music information, and the data cassette is used as a dedicated cassette for data recording.

In the past, in order to distinguish between the two cassettes, a splicing tape for connecting a magnetic tape and a leader tape provided with a non-transparent tape identification pattern was used as a data cassette, and the tape identification pattern was used. There is no DAT cassette. The tape identification pattern is recognized by the detection mechanism provided in the drive device.

In the detection mechanism, the light emitted from the light emitting portion of the sensor toward the inside of the cassette main body is irradiated onto the tape identification pattern through the prism provided inside the cassette main body, and the return light is detected. The type of tape is identified by receiving the light from the light receiving portion of the sensor.

By the way, the tape identification pattern is
As a rectangular pattern having a size defined by the standard, one pattern is provided on the splicing tape, or two patterns are provided at predetermined intervals. On the other hand, the prism is made of a transparent resin and is molded integrally with a window member that constitutes the upper half transparent window portion with a size that is also defined by the standard.

[0007]

However, due to the relationship between the prism and the shape of the tape identifying pattern, the light may not be blocked by the tape identifying pattern and may leak. If the light leaks, the sensor cannot recognize that the light is blocked, and the tape type cannot be identified. As a result, although the data cassette was attached to the drive device, the data cassette was
It may be recognized as a T cassette and may be ejected from the drive device.

As described above, although the dimensions of the prism and the dimensions of the tape identification pattern have been determined according to the standard, no consideration has been given to the prevention of light leakage in the prism.

Therefore, an object of the present invention is to provide a tape cassette which can accurately identify the type of tape stored in the cassette body.

[0010]

The present invention provides a splicing tape that connects a magnetic tape and a leader tape with light emitted from a sensor toward the inside of a cassette body through a prism provided inside the cassette body. In a tape cassette in which a light-impermeable tape identification pattern is provided and the presence or absence of return light is received by the sensor to identify the tape type, the traveling direction of the emitted light The above object is achieved by providing a tape cassette characterized in that light leakage prevention means are provided on both side surfaces of the prism along the.

Further, according to the present invention, the above object is achieved by providing a tape cassette according to claim 1, wherein both side surfaces of the prism are painted black as the light leakage preventing means. It is a thing.

Further, the present invention achieves the above object by providing a tape cassette according to claim 1, characterized in that, as the light leakage preventing means, both side surfaces of the prism are roughened. It is a thing.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the tape cassette of the present invention will be described below with reference to the drawings. In this embodiment, the present invention is applied to a data cassette.

FIG. 1 is an enlarged sectional view showing an essential part showing a detection mechanism portion, FIG. 2 is an enlarged perspective view showing an essential part of a portion where a prism is provided, and FIG. It is a perspective view.

In the tape cassette of this embodiment, as shown in FIGS. 1 to 3, the light H ₁ emitted from the light emitting portion 2 of the sensor 1 toward the inside of the cassette body 4 is provided inside the cassette body 4. Optically opaque tape identification patterns 9 and 1 provided on the splicing tape 8 that connects the magnetic tape 6 and the leader tape 7 via the prism 5.
It is a tape cassette in which the type of tape is discriminated by irradiating it to 0 and receiving the presence or absence of the return light H ₂ by the light receiving section 3 of the sensor 1.

The tape cassette of this embodiment will be further described. The prism 5 is, as shown in FIGS. 2 and 3,
A window member 12 made of a transparent resin, which is provided so as to cover the window portion for confirming the remaining amount of the tape opened in the upper half 11.
And are integrally formed. The prism 5 includes a light introducing section 13 for guiding the light H ₁ emitted from the light emitting section 2 of the sensor 1 into the cassette body 4, and an optical path polarizing section 14 provided at one end of the light introducing section 13. And has a substantially L-shaped cross section.

As shown in FIGS. 2 and 3, the light introducing portion 13 has a light receiving hole 15 formed in the side surface of the cassette body 4.
It serves to guide the light H ₁ incident on the inside of the cassette body 4 to the optical path polarization section 14. The light introducing portion 13 is integrally formed at the base end portion of the window member 12 as a rectangular parallelepiped whose longitudinal direction is along the optical path of the light H ₁ .

On the other hand, as shown in FIGS. 2 and 3, the optical path polarization section 14 is provided by the light introduction section 13 to the cassette body 4 as shown in FIG.
It serves to change the optical path of the light H ₁ guided inside. That is, the optical path polarization unit 14 changes the direction of the light H ₁ guided into the cassette body 4 by the light introduction unit 13 and uses the light H ₁ as return light H ₂ from inside the cassette body 4 to the cassette body 4. The light is returned to the light receiving portion 3 of the sensor 1 through the light emitting hole 16 formed on the side surface of the sensor.

As shown in FIGS. 2 and 3, the optical path polarization section 14 has a substantially trapezoidal cross section, and is formed at one end of the light introduction section 13 so as to rise toward the inside of the cassette body 4. . The optical path polarization section 14 is provided with a pair of reflecting surfaces 17, 18 inclined at 45 degrees for changing the optical path of the light H ₁ guided from the light introducing section 13. The reflection surfaces 17 and 18 are provided at the tip and the base of the optical path polarization unit 14, respectively, and the directions of the inclined surfaces are opposite to each other.

On the other hand, at the winding end position of the magnetic tape 6, as shown in FIG. 3, a transparent splicing tape 8 is provided.
A transparent leader tape 7 is also connected via. The splicing tape 8 has tape identification patterns 9 and 10 indicating that it is a magnetic tape for data.
, Are provided at a predetermined interval. The tape identification patterns 9 and 10 are provided as light-impermeable rectangular patterns.

In this tape cassette, light leakage prevention means 19 and 20 are provided on both side surfaces of the prism 1 along the traveling direction of the emitted light H ₁ .
As shown in FIGS. 2 and 3, the light leakage preventing means 19 and 20 are formed by blackening or roughening both side surfaces of the prism 5. In the drawing, the light leakage prevention means 19 and 20 are shown as diagonal lines.

If the both sides of the prism 5 are painted black by coating the both sides of the prism 5 with a magnetic tape or the like, a diffused reflection (light leakage) at the prism 5 part is achieved. Can be prevented.

If the both sides of the prism 5 are sanded to make unevenness, or if the mold used to mold the prism 5 is made rough to make unevenness, the light at the prism 5 part is still produced. Diffuse reflection can be prevented.

As described above, if the light leakage preventing means 19 and 20 are provided on both side surfaces of the prism 5, the return light H ₂ returning from the prism 5 to the light receiving portion 3 of the sensor 1 is not in the original optical path. It does not spread in the direction, and it is possible to prevent diffuse reflection of light at the prism 5 part. Therefore, when the tape identification patterns 9 and 10 come to the position facing the prism 5, the prism 5 is moved by the tape identification patterns 9 and 10.
It is possible to reliably block the return light H ₂ returning from the sensor to the sensor 1.

As a result, the sensor 1 can recognize that the light is blocked, and can surely recognize that the data cassette contains the magnetic tape 6 for data. Therefore, if the DAT cassette is erroneously attached to the drive device dedicated to the data cassette, the sensor 1 does not recognize the tape identification patterns 9 and 10, and the DAT cassette is ejected.

Further, in this tape cassette, since the light-transmissive leader tape 7 is provided at the end of the light-impermeable magnetic tape 6, the drive device changes from the light blocking state to the light transmitting state. It is also possible to know the tape end of the magnetic tape 6 by detecting it with the sensor 1. Therefore, by sending a tape stop signal to the tape drive system of the drive device, the drive of the magnetic tape 6 can be stopped before the magnetic tape 6 is damaged.

[0027]

According to the tape cassette of the present invention, since the light leakage preventing means is provided on both side surfaces of the prism,
It is possible to provide a tape cassette that can accurately identify the type of tape accommodated in the cassette body.

[Brief description of drawings]

FIG. 1 is an enlarged sectional view of an essential part showing a detection mechanism portion in a tape cassette of the present invention.

FIG. 2 is an enlarged perspective view of an essential part of a portion where a prism is provided in the tape cassette of the present invention.

FIG. 3 is an enlarged perspective view of an essential part showing a correspondence relationship between a prism and a tape identification pattern in the tape cassette of the present invention.

[Explanation of reference numerals] 1 sensor 2 light emitting part 3 light receiving part 4 cassette body 5 prism 6 magnetic tape 7 leader tape 8 splicing tape 9,10 tape identification pattern 19,20 light leakage prevention means

Claims (3)

[Claims] 1. A light opaque material provided on a splicing tape for connecting a magnetic tape and a leader tape to light emitted from a sensor toward the inside of the cassette body via a prism provided inside the cassette body. In both sides of the prism along the traveling direction of the emitted light, in a tape cassette in which the tape identification pattern is irradiated and the presence or absence of the returned light is received by the sensor to identify the type of tape. A tape cassette characterized in that a light leakage prevention means is provided in the. 2. The tape cassette according to claim 1, wherein the light leakage prevention means is provided with black coating on both side surfaces of the prism. 3. The tape cassette according to claim 1, wherein the light leakage prevention unit has rough surfaces on both sides of the prism.