JPH0355906B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cassette pack in which tape ends can be detected without being affected by outside air.

The first cassette pack used in digital audio tape recorders (DAT).
As shown in the figure, a structure having a detection hole for optically detecting the end of the tape may be considered. In the figure, 1 is a case, 2 and 3 are a supply hub and a take-up hub, and 4 is a tape that is wound between both hubs 2 and 3, and the part that contacts the magnetic head is always exposed from the side of the case 1. 5 is a through hole provided in the thickness direction of the case 1; 6 is a through hole provided in the side surface of the case 1; 7 is a light source for irradiating light from the through hole 6; and 8 is a through hole provided in the through hole 5. This is an optical sensor that is inserted to detect light from a light source 7, and the through hole 5 and the through hole 6 are provided in portions located on both sides of the tape 4. Here, the through hole 5 and the passage hole 6 are provided so as to function as detection holes and optically detect the end of the tape 4.

FIGS. 2 and 3 are a top view and a sectional view showing the structure of the cassette pack including the detection hole, particularly the end portion.

In the above configuration, a part of the light generated by the light source 7 passes through the through hole 6 and passes through the tape 4 to the through hole 5.
reach within. As a result, the optical sensor 8 inserted into the through hole 5 detects the amount of light that has arrived, but since a leader tape is provided at the end of the tape 4, which is more transparent than the magnetic material, the tape 4 is Since the amount of light reaching the optical sensor 8 changes as it reaches the end, the optical sensor 8 can optically detect the end of the tape 4 by detecting this change in the amount of light.

By the way, in such a conventional cassette pack, the through hole 5 and the passage hole 6, which serve as detection holes, are both left open and are in contact with the outside air, making it easy for dust etc. to pass through these detection holes. However, there was a drawback that it penetrated into Case 1.

For this reason, there is a risk that problems such as deterioration of the tape properties and difficulty in running the tape smoothly may occur.

The present invention has been made in response to the above problems, and includes a cylindrical member having a shape that allows an optical detection means to be inserted into the through hole, and at least a portion of which is made of a highly transparent material. To provide a cassette pack which eliminates the conventional drawbacks by providing a cover member made of a highly transparent material in the hole and forming an integrated structure between the cylindrical member and the cover member via an intermediate member. The purpose is to

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

4 and 5 are a top view and a sectional view showing a cassette pack according to an embodiment of the present invention, in which the same parts as in FIG. 1 are designated by the same numbers, and 9 is a cylindrical member made of a highly transparent material. It has a shape into which an optical detection means such as a photosensor can be inserted, and is provided so as to fit into the through hole 5 . Reference numeral 10 denotes a lid member similarly made of a highly transparent material, and is provided to fit into the passage hole 6. This lid member 10 and the cylindrical member 9 are connected via an intermediate member 11 made of the same material. It has an integrated structure.

FIGS. 6a and 6b are a top view and a sectional view showing the structure of this integrated member 12, in which the cylindrical member 9 and the lid member 1
0 through an intermediate member 11.
Reference numeral 13 denotes a hole provided in a part of the intermediate member 11, which allows the light to pass through the intermediate member 11 when it passes from the lid member 10 toward the cylindrical member 9 as shown by the arrow in FIG. 6b. This is to prevent the water from reaching the cylindrical member 9. That is, such a hole 13
By providing this in the intermediate member 11, it is possible to narrow the optical path for the light that has proceeded to an unnecessary portion, thereby producing an effect of increasing the optical path resistance.

Such considerations can prevent errors in detection operations caused by unnecessary light.

To assemble the cassette pack according to the above embodiment, first, as shown in FIG.
The integrated member 12 is fitted into the through hole 5a and the through hole 6a provided in the through hole 5a and the through hole 6a, and then the upper part 1b of the case 1 is inserted from above so that the through hole 5b and the through hole 6b corresponding to the through hole 5a and 6a are After being overlapped so as to be fitted into the integrated member 12, they are screwed together.

Although the above example shows the case where the optical sensor 8 is inserted into the through hole 5 and the light source 7 is arranged near the through hole 6, the positions of the optical sensor 8 and the light source 7 may be reversed.

Further, a light reflecting member may be disposed within the through hole 5, and a light source and light sensor may be disposed near the passage hole 6. Furthermore, the positions of the light reflecting member and the light source and light sensor can be reversed.

Note that the through hole 5 may also serve as a reference hole for positioning the cassette pack.

The shapes of the through hole 5 and the cylindrical member 9 are square;
Any shape can be selected, including a circular shape.

Similarly, the shape of the passage hole 6 can be arbitrarily selected.

In the above embodiment, an example was described in which the entire integrated member 12 was made of a highly transparent material, but as shown in FIG.
The other portion 12b may be made of an opaque material. In addition, without directly inserting optical detection means such as a light sensor, a light source, a light reflection member, etc. into the through hole 5, a prism 14 is inserted as shown in FIG. You may also place .

FIGS. 9 to 12 show other structures for increasing the optical path resistance for light traveling to unnecessary portions. 9 shows a structure in which the thickness of the intermediate member 11 is reduced, FIGS. 10 and 11 show a structure in which a certain angle is provided at the bottom end 11a of the intermediate member 11 to suppress the path of light, and The figure shows a structure in which the intermediate member 11 is provided in a stepped manner.

Furthermore, the structures shown in FIGS. 9 to 12 and FIG. 6 may be combined as appropriate.

Furthermore, FIGS. 13a and 13b show another embodiment of the present invention, in which the shape of the lid member 10 fitted into the passage hole 6 is shaped like a lens, and the shape of this lens is set on one surface side. The structure is such that a focal point is formed at the center of the optical axis of the optical detection means 15a or 15b inserted into the cylindrical member 9, and parallel light rays are formed on the other surface side. . This allows the light to be concentrated within the through hole 5, thereby improving the efficiency of light detection and, in turn, improving the detection performance.

As is clear from the above explanation, according to the present invention,
A cylindrical member having a shape that allows the optical detection means to be inserted into the through hole and at least a part of which is made of a highly transparent material is provided, and a lid member made of a highly transparent material is provided in the through hole. Since the cylindrical member and the lid member are integrated with each other via the intermediate member, both the through hole and the passage hole are shielded from the outside air, so that the inside of the case cannot be detected through the detection hole. It is possible to prevent dust, etc., from entering.

Therefore, the tape end can be detected without being affected by the outside air.

[Brief explanation of drawings]

Fig. 1 is a perspective view showing a conventional example, Figs. 2 and 3 are both a top view and a sectional view showing the conventional example, and Figs. 4 and 5 are a top view and a sectional view showing an embodiment of the present invention. , FIGS. 6a and 7 are both a top view and a perspective view showing an embodiment of the present invention, FIG. 6b, and FIGS. 8 to 12 are sectional views showing an embodiment of the present invention, and FIG. 13 is a top view and a perspective view showing an embodiment of the present invention. Figures a and b are schematic diagrams showing embodiments of the present invention. 1...Cassette case, 4...Tape, 5,5
a, 5b... Through hole, 6, 6a, 6b... Passing hole, 7... Light source, 8... Light sensor, 9... Cylindrical member, 10... Lid member, 11... Intermediate member, 12
...integrated member, 13... hole, 14... prism,
15, 15a, 15b... optical detection means.

Claims (1)

[Scope of Claims] 1. A cassette pack in which a through hole and a passage hole are provided in the thickness direction of the case and on the side thereof, respectively, so as to be located on both sides of the tape in order to optically detect the end of the tape. A cylindrical member having a shape such that an optical detection means can be inserted into the hole and at least a part of which is made of a highly transparent material is provided, and a lid member made of a highly transparent material is provided in the passage hole. A cassette pack characterized in that the cylindrical member and the lid member are integrated with each other via an intermediate member. 2. The cassette pack according to claim 1, wherein the cylindrical member is entirely made of a highly transparent material. 3. The cassette pack according to claim 1 or 2, wherein the intermediate member has a shape that increases optical path resistance. 4. The lid member is shaped like a lens, and the shape of the lens is such that a focal point is formed at the center of the optical axis of the optical detection means inserted into the cylindrical member on one surface side, and parallel light rays are formed on the other surface side. Claim 1 characterized in that it is configured so that
The cassette pack according to any one of items 1 to 3. 5. The cassette pack according to any one of claims 1 to 4, wherein the through hole into which the cylindrical member is inserted is used as a reference hole for a cassette device.