JPH0458664B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a leader tape detection device that optically detects a leader tape provided at the end of a tape body housed in a tape cassette.

[Conventional technology]

Conventionally, a transparent leader tape having optical transparency is provided at the end of a magnetic tape housed in a tape cassette in the running direction. This leader tape is made of a material that is mechanically stronger than the magnetic tape. And the magnetic tape
The leader tape is clamped to a reel hub rotatably supported within the cassette half and housed within the cassette half.

Focusing on the fact that a transparent leader tape is provided at the end of the magnetic tape, the end of the magnetic tape is detected by detecting this leader tape using an optical detection means. Detection devices have been used in the past. This type of detection device is designed to operate on either side of the running path of the magnetic tape inside the cassette half or the running path of the magnetic tape pulled out from the cassette half and running.
It is composed of a light emitting element such as an LED and a light receiving element that receives light from the light emitting element. That is, when the tape cassette is installed in a tape recorder, the light emitting element is placed in a position where it can be inserted into a light emitting element housing formed in the cassette half at a position opposite to one side of the tape running path in the cassette half. will be placed. On the other hand, the light receiving element is located at a position opposite to a through hole formed in the side surface of the cassette half facing the tape running path within the cassette half;
Alternatively, it is provided at a position facing the magnetic tape that is pulled out from the cassette half and runs.

The leader tape is detected by using a light receiving element to detect the light transmitted from the light emitting element when the leader tape passes through the optical path from the light emitting element to the light receiving element. The end of the tape is detected.

Furthermore, a device configured as described in Japanese Utility Model Application Publication No. 58-7240 has also been proposed.

[Problem that the invention seeks to solve]

As described above, in a leader tape detection device configured to have a light emitting element and a light receiving element that receives light from the light emitting element arranged on both sides of the running path of the magnetic tape, a light emitting element storage part is provided in the cassette half. This makes it difficult to further reduce the size of the tape cassette while improving the storage density of magnetic tapes.

In addition, in the case where the light emitting element faces into the cassette half, it is necessary to erect a support pillar on the tape cassette mounting surface of the recording/reproducing apparatus and install the light emitting element through this support pillar. This has become a problem in reducing the size of recording and reproducing devices.

Furthermore, since the light-emitting element is located inside the cassette half and the light-receiving element is located outside the cassette half, the electrical connection wires drawn out from the light-emitting element and the light-receiving element become long.
The mounting space for the light-emitting element and the light-receiving element becomes large, which poses a problem in reducing the size of a recording/reproducing apparatus in which this leader tape detection device is installed.

In addition, the device described in Japanese Utility Model Application Publication No. 58-7240 provides a U-shaped light guide member in the cassette half, and arranges a light emitting element and a light receiving element to face the light guide member. This tape cassette detects the leader tape running inside the tape cassette, but since the entire optical guide member is placed inside the cassette half, it is possible to improve the storage density of magnetic tapes and achieve further miniaturization. It is extremely difficult to apply this method to That is, in this type of small tape cassette, it is extremely difficult to secure sufficient space within the cassette half to accommodate the entire optical guide member. Furthermore, since the device described in the above-mentioned publication has a light emitting element and a light receiving element arranged in parallel in the running direction of the tape body, it is extremely difficult to apply it to a magnetic recording/reproducing apparatus using a small tape cassette. In other words, in the case of a magnetic recording/reproducing apparatus using a small tape cassette, it is not possible to provide sufficient space in the running direction of the tape body running inside the cassette half, so the light emitting element and the light receiving element are placed in the running direction of the tape body. It is not possible to obtain enough space to install the two in parallel.

Furthermore, in what is described in the above publication, the light from the light emitting element to the light receiving element is transmitted twice through the tape body running on the tape running path, so the attenuation of the light is large and the reliability is high. There is also a possibility that the leader tape may not be detected.

Therefore, the present invention aims to solve the above-mentioned problems, and achieves further miniaturization of tape cassettes while improving the storage density of magnetic tapes, thereby making it possible to miniaturize recording and reproducing apparatuses that use such small tape cassettes. This was proposed for the purpose of providing a leader tape detection device that contributes to the above-mentioned problems and further improves the reliability of leader tape detection.

[Means for solving problems]

In order to solve the above-mentioned problems of the conventional tape and to achieve the above-mentioned objects, the present invention provides a light-transmitting leader tape at at least one end of the recording tape in the running direction. is,
In a leader tape detection device for detecting the leader tape of a tape body stored in a cassette half and running in a tape running path configured in the cassette half, A light guide is provided from one side edge to a position facing at least a part of the plane of the tape body, an optical path passing through the light guide and intersecting the tape running path is formed, and a light introduction part of this optical path is formed. The light guide portions are arranged in parallel in the width direction of the tape body running on the tape running path, and a light source that irradiates the light introduction portion with light and a light source that irradiates the light introduction portion and is guided to the optical path. A light receiving element for detecting the light passing through the light guide part is arranged in the width direction of the tape body in correspondence with the light introduction part and the light guide part, respectively, and a leader tape of the tape body passes in the light path. This is detected by the light receiving element.

[Effect]

The leader tape detecting device according to the present invention emits light from a light emitting element, irradiates the light introduction part, and detects at least one of the flat surfaces of the tape body from one side edge in the width direction of the tape body running on the tape running path in the cassette half. The leader tape is detected by using a light receiving element to detect the light that has passed through the light guide through a position facing the tape guide section and the light guide section through an optical path that intersects with the tape running path.

〔Example〕

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

As shown in FIGS. 1 and 2, the leader tape detection device according to the present invention includes a light guide 14 that accommodates the tape body 7 of the tape cassette 1 and is disposed in a part of the cassette half 6; The tape cassette 1 is equipped with a light emitting element 2 such as an LED disposed on the side of a magnetic recording/reproducing apparatus such as a tape recorder, and a light receiving element 3 which is a light detecting element that receives light from the light emitting element 2. There is.

The tape cassette 1, in which the light guide 14 constituting the leader tape detection device according to the present invention is integrally disposed and stores the magnetic tape 7, is formed by butting and joining a pair of upper and lower halves 4 and 5 to each other. It is equipped with a cassette half 6. A pair of tape reels (not shown) are rotatably supported within the cassette half 6, and the tape body 7 is wound and housed between these tape reels. This tape body 7 is composed of a magnetic tape 7a and a transparent leader tape 7b having a predetermined length and having optical transparency on the tape reel fixed end side which is the longitudinal end of the magnetic tape 7a.

The cassette half 6 in which the tape body 7 is wound and stored is made of an opaque synthetic resin that does not have light transmittance, and has openings on both sides of the front side through which the tape body 7 is drawn out. Sections 8 and 9 are provided. The tape body 7 is pulled out from each of the openings 8 and 9, extends to the front side of the cassette half 6, and runs from one tape reel to the other tape reel. Also,
On the front side of the cassette half 6, there is a recess 10 into which a loading mechanism, etc., which hooks the tape body 7 extending on the front side of the cassette half 6 and loads it onto a predetermined tape running path in the recording/reproducing apparatus, enters. It is provided. Furthermore, a front cover 11 is rotatably attached to the front side of the cassette half 6 to cover and protect the tape body 7 extending to the front side. This front lid 11 has a lid portion 11
Rotating pieces 11b, 11b provided on both sides of a
The cassette half 6 is rotatably mounted by engaging rotation pins 12 protruding from the inner surface thereof into engagement holes 13 formed on both sides of the cassette half 6. The front cover 11 is
When the front side of the cassette half 6 is closed,
The lid is locked by a locking mechanism (not shown) to prevent the lid from being opened inadvertently.

By the way, the rotating pieces 11b, 11b of the front cover 11 near the respective openings 8, 9 of the cassette half 6
Light guides 14, 14 made of a transparent synthetic resin having light transmittance are provided so as to be buried in the positions covered by the . That is, the light guides 14, 14 are integrally formed with the cassette half 6, and are arranged so as to constitute a part of the cassette half 6.

Each of the light guides 14, 14 is formed in a substantially L-shape and is provided extending from the bottom side of the lower half 5 to the inner side surface of the cassette half 6 of each of the openings 8, 9. That is, the light guide 14 is
As shown in FIGS. 1 and 2, the opening 8,
The tape member 7 is provided from one edge side in the width direction of the tape body 7 on the nine tape running paths to a position facing at least a part of one plane of the tape body 7 .
One end of the horizontal portion 14a extending on the bottom surface of the lower half 5 of the light guide 14 fits into a notched recess 15 formed by cutting out the side surface of the lower half 5, as shown in FIG. and its end face faces the outside of the cassette half 6. Further, as shown in FIG. 3, the horizontal part 14a of the light guide 14 and the vertical part 14b rising on the inner side surface of the openings 8 and 9 intersect with each other on the outer side surface of the bent part. A first reflecting surface 16 is provided which reflects the light transmitted through the portion 14a at 90 degrees and guides it to the vertical portion 14b at an inclination angle of 45 degrees. Furthermore, the vertical portion 1
At the tip of the cassette half 6, there is a second reflective surface 17 that faces the first reflective surface 16 and further reflects the light passing through the vertical portion 14b by 90 degrees toward the outside of the cassette half 6. It is provided. By forming the light guide 14 in this way, the horizontal portion 1
A U-shaped optical path 1 is formed from 4a through the vertical portion 14b, intersecting the tape body 7 on the tape running path in the openings 8 and 9, and heading outward of the cassette half 6.

Note that the first reflective surface 16 is connected to the cassette half 6.
Since it faces the recess 10, there is a risk that the loading mechanism etc. may come into contact with it. Therefore, in order to prevent damage from these loading mechanisms and the like, a protective film 18 is formed on the outer surface.

The end surface of the horizontal portion 14a fitted into the notch recess 15 of the lower half 5 of the light guide 14 faces the side surface of the cassette half 6 and serves as a light introducing portion 19. In addition, the light guide 14 of the cassette half 6
A light transmitting opening is formed in parallel with the horizontal part 14a on one side opposite to the second reflective surface 17 provided at the end of the vertical part 14b, and the light guiding part is formed with this opening. 20.

On the other hand, on the side of the recording/reproducing apparatus into which the tape cassette 1 is mounted, a light emitting element 2 consisting of an infrared light emitting element or the like is provided facing the light introduction section 19 of the tape cassette 1 mounted therein, and the light emitting element 2 is provided with an infrared light emitting element or the like. A light receiving element 3 made of an infrared detecting element or the like is provided opposite to the portion 20 . By providing the light emitting element 2 and the light receiving element 3 in this way, the light emitted from the light emitting element 2 passes through the optical path 1 constructed using the light guide 14 in the tape cassette 1 and is received. Detected by element 3.

Then, the tape body 7 in the tape cassette 1 travels from one tape reel to the other tape reel in the forward direction of arrow A in FIG. Then, the transparent leader tape 7b provided at one end of the tape body 7 reaches a tape running path corresponding to the light guide 14 provided near one opening 8 of the cassette half 6. When the leader tape 7b reaches the tape running path corresponding to the light guide 14 in this way, the light from the light emitting element 2 that was blocked by the opaque magnetic tape 7a is transferred to the leader tape 7b.
b, passes through the above-mentioned optical path 1 intersecting this leader tape 7b, and is detected by the light receiving element 3. This light-receiving element 3 allows the light-emitting element 2 to
By detecting the light from the leader tape 7b at the end of the tape body 7, one end of the tape body 7 is detected.

Also, the tape body 7 in the tape cassette 1 travels in the opposite direction to the direction of arrow B in FIG. Then, the leader tape 7b provided at the other end of the tape body 7 reaches the tape running path corresponding to the light guide 14 provided near the other opening 9 of the cassette half 6, and the same process as described above is carried out. The light from the light emitting element 2 is detected by the light receiving element 3, the leader tape 7b at the end of the tape body 7 is detected, and the other end of the tape body 7 is detected.

Note that the leader tapes 7b provided at each end of the tape body 7 are connected to the respective light guides 14 provided on both sides of the cassette half 6, when the tape body 7 is wound onto one or the other tape reel. The length does not exceed 14.

Further, in the above embodiment, the light emitting element 2 and the light receiving element 3 are installed independently in the device, but as shown in FIG. It is also possible to use a composite light emitting/receiving element 24 that accommodates three. Even when this composite type light emitting/receiving element 24 is used, the light emitting element 2 is opposed to the light introducing part 19 of the tape cassette 1, and the light receiving element 3 is opposed to the light leading part 20.

Furthermore, in the above embodiment, the cassette half 6
is made of a material that does not transmit light, and a second reflective surface 16 is formed using the cassette half 6 as a reflective surface.
However, in the case where the light guide 1 is made of a material having optical transparency, the light guide 1
The second reflective surface 16 may be formed by forming a light reflective film on the second reflective surface 4 .

Furthermore, the light guide 14 extends from one side edge in the width direction of the tape body 7 on the tape running path in the cassette half 6 along which the tape body 7 fed out from the tape reel travels. forming an optical path that faces and intersects the tape running path;
Light emitting element 2 provided outside the cassette half 6
If the light introducing section 19 and the light guiding section 20 facing each other with respect to the light receiving element 3 can be constructed, it is not necessary to provide them near the openings 8 and 9 of the cassette half 6; It may be provided at any position corresponding to the tape running path.

〔Effect of the invention〕

As described above, the present invention provides a light guide in a part of the cassette half, forms an optical path that intersects the tape body on the tape running path inside the cassette half through the light guide, and extends the tape outside the tape cassette. Since the leader tape can be detected by a light emitting element and a photodetecting element placed on one side, it is necessary to provide a part in the tape cassette for positioning the light emitting element, etc., which reduces the storage density of the magnetic tape. Further miniaturization of the tape cassette can be achieved while improving the tape cassette.

Furthermore, since the light-emitting element and the light-detecting element can be located outside the tape cassette, there is no need to route wires connecting the light-emitting element and the light-detecting element, and the light-emitting element can be placed facing inside the tape cassette. Since there is no need for supporting columns or the like, the installation space for configuring the leader tape detection device can be reduced, and the recording/reproducing device itself can be miniaturized.

In particular, the light introducing part and the light leading part of the optical path are arranged in parallel in the width direction of the tape body running on the tape running path, and the light source and light receiving part are arranged corresponding to the light introducing part and the light leading part, respectively. Since the elements are arranged in the width direction of the tape body, they can be arranged in parallel in the thickness direction of the tape cassette installed in the recording and reproducing apparatus, and the recording and reproducing apparatus using the small tape cassette can be made even more compact. can be achieved.

Furthermore, since the optical path that intersects the tape running path is configured to intersect the tape body only once, the light transmitted from the light source is attenuated less and reliability in detecting the leader tape can be improved.

Furthermore, since the light guide is formed so as to extend from one side edge in the width direction of the tape body running on the tape running path to a position facing at least a part of the plane of the tape body, the above-mentioned implementation is possible. As is clear from the example, since it can be constructed integrally with the cassette half so as to constitute a part of the cassette half, it can be constructed efficiently using a small tape cassette with little storage space.

[Brief explanation of the drawing]

FIG. 1 is a schematic perspective view showing a leader tape detection device according to the present invention, FIG. 2 is a perspective view of essential parts of the leader tape detection device, and FIG. 3 is a light guide and a FIG. 3 is a cross-sectional view of a main part showing a formed optical path. FIG. 4 is a perspective view showing an element that is a combination of a light emitting element and a light receiving element. 1...Tape cassette, 2...Light emitting element, 3...
...Photodetection element, 6...Cassette half, 7...Tape body, 7a...Magnetic tape, 7b...Leader tape, 14...Light guide, 16...First reflective surface,
17...Second reflective surface, 19...Light introduction part, 20
...Light guide section.

Claims (1)

[Scope of Claims] 1. A tape that is provided with a light-transmitting leader tape at at least one end in the running direction of the recording tape, is housed in a cassette half, and runs in a tape running path configured within the cassette half. In a leader tape detection device for detecting the leader tape on a body, a light guide extends from one edge in the width direction of the tape body running on the tape running path to a position facing at least a part of the plane of the tape body. and forming an optical path passing through the light guide and intersecting the tape running path, and a light introducing part and a light leading part of this optical path are arranged in parallel in the width direction of the tape body running on the tape running path. , a light source that irradiates the light introduction section with light, and a light receiving element that detects the light that is irradiated to the light introduction section, guided to the optical path, and passed through the light output section, is connected to the light introduction section and the light output section. A leader tape detection device characterized in that the leader tape detection device is arranged in the width direction of the tape body so as to correspond to each of the above, and the light receiving element detects that the leader tape of the tape body passes through the optical path.