JPH06215445A - Tape deck - Google Patents

Abstract

PURPOSE:To prevent a light receiving element from generating a sensitivity deterioration and a malfunction due to the incident of an external light on the light receiving element by covering the circumference from the vicinity of reflecitng surface of a tape deck to the light receiving element with a cylindrical body. CONSTITUTION:Since the cylindrical body 31 consists of an opaque member and covers the vicinity of a reflecting plate 32 and an optical path from the vicinity of the reflecting plate 32 to the light receiving element 26, the reflecting plate 32 and the optical path to the light receiving elemet are interrupted from the external light beam. Therefore, only the light from a light emitting element is guided to the light receiving element 26. Consequently, the sensitivity of the light receiving element 26 is excellent, and no mal function occurs. Also, an auxiliary pronted circuit board and a lead wire between the auxiliary printed circuit board and a main pronted circuit board are dispensed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a tape deck,
For example, the present invention relates to a tape deck having a detection device for detecting the start or end of a cassette tape incorporated in a cassette tape recorder. The signal handled by the tape deck may be video, audio, digital, a combination thereof, or any other form.

[0002]

2. Description of the Related Art Generally, as a device for detecting the beginning and end of a tape on a tape deck, a light emitting element is provided at the center of the tape deck, and light receiving elements are provided on both sides of the tape deck so that the light from the light emitting element is emitted. The tape end is detected by hitting the tape for detecting the tape end provided at the beginning and the end of the tape and receiving the transmitted light by the light receiving element. As a conventional device for detecting the beginning and end of the tape, there is, for example, one shown in FIGS. An auxiliary printed board 53 for mounting the light receiving element 52 at a position where the light emitted from the light emitting element 51 provided in the central portion of the chassis 57 of the tape deck 50 can be received is attached to the side wall 57a of the deck chassis 57. There is one in which the light receiving element 52 is soldered to 53 and the main printed circuit board 54 and the auxiliary printed circuit board 53 on the lower side of the deck chassis are connected by a lead wire 55.

As another example, as shown in FIG. 10, there is a prism cylindrical body 56 made of a transparent resin such as acrylic resin and having an inclined surface 56a. The light beam from the light emitting element 51 is introduced through the prism tube body 56, reflected by the inclined surface 56a, guided to the lower end surface of the prism tube body 56, and guided to the light receiving element 52 on the main printed circuit board 54 installed at this position. Then
The light receiving element 52 receives light.

[0004]

However, in such a conventional tape end detecting device, the periphery of the light receiving element 52 is open, so that not only the light ray from the light emitting element 51 but also the external light is received. There is a problem that the amount of light rays that enter the light receiving element 52 and enter the light receiving element 52 increases, and the sensitivity of the light receiving element 52 decreases, or malfunction occurs.

Further, when the transparent resin prism cylinder 56 as shown in FIG. 10 is used, even if a light ray from the outside does not directly enter the light receiving element 52, if it enters the prism cylinder 56, the prism cylinder 56 There is a drawback that it hits the wall surface of the body 56, is reflected, and is guided to the light receiving element 52 to cause the above-mentioned problems. Further, the position of the light receiving element 52 on the main printed circuit board 54 is determined by the position of the prism cylinder 56, and it may be difficult to change it. Therefore, the position adjustment of the prism cylinder 56 for adjusting the light reception by the light receiving element 52 is possible. There was a problem that it was difficult.

Therefore, according to the first aspect of the invention, light is emitted by covering the vicinity of the reflection plate that reflects the light from the light emitting element to the light receiving element side and the circumference of the optical path of the light to the light receiving element with a non-transparent member. It is an object of the present invention to prevent the sensitivity of the light receiving element from being lowered or malfunction by making the light receiving element receive only the light beam from the element.

According to a second aspect of the present invention, the tubular body according to the first aspect of the present invention is a tubular body having a U-shaped cross section and a lid body connected to an upper portion of the tubular body, and is developed in a plane. By enabling it, it can be made with one injection molded part,
It is an object of the present invention to make the manufacturing easy and inexpensive.

[0008]

The invention according to claim 1 is
In a tape deck equipped with a light emitting element and a light receiving element that detect the beginning and end of the tape, a reflecting plate that has a reflecting surface that reflects the light from the light emitting element to the light receiving element side and a reflection plate that is made of an opaque member A cylindrical body that covers the vicinity of the plate and the periphery of the optical path of the light to the light receiving element is provided.

According to a second aspect of the present invention, in addition to the above structure, the tubular body is a tubular main body having a U-shaped cross section, which extends from the side of the reflector holding the reflector to the side of the light receiving element. A lid body having a light guide hole for connecting to the light emitting element and a lid body having a lockable engagement part at the other side end, the lock part being connected to one side end of the upper part of the cylinder main body; When separated from the other side end, the cylindrical main body and the lid body can be developed in a plane.

[0010]

In the invention described in claim 1, the cylindrical body is made of an opaque member and covers the vicinity of the reflector and the optical path of the light to the light receiving element. The optical path is blocked from external rays, and only the light from the light emitting element is guided to the light receiving element.

According to the second aspect of the present invention, the tubular body is made of an opaque member, and is made up of a tubular body having a U-shaped cross section and a lid body that can be connected and locked to the upper portion of the tubular body. Since it can be expanded in a plane, the cylindrical body can be mass-produced in a plane by using, for example, a synthetic resin as an opaque member.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. 1 and 2 are views showing an embodiment of the tape deck according to the present invention. First, the configuration will be described. In FIGS. 1 and 2, 1 is a deck chassis having a rectangular shape in plan view, 2 is a rotatable head cylinder to which a recording / playback head and the like are attached, and 3 and 4 are slide bodies 7 and 8 which slide and guide via rails 5 and 6. Video cassette 9
, A tape loading pin for winding the magnetic tape 9a around the cylinder 2, a supply and take-up reel shaft for supporting the tape reel of the cassette 9 as an engaging shaft, a head 12 for inputting and outputting an audio signal and the like, 13 Is an erasing head, 14 is a capstan, and 15 is a pinch roller.

In the figure, 16 is a cassette holder for supporting the cassette 9, 17 and 17 are erected on the upper surface of the chassis 1, and the cassette holder 16 is movably attached to the cassette 9 in / out position or recording / reproducing position. Left and right guide plates, 19 is a tape running motor (flywheel) for rotating the capstan 14, and 20 is a loading motor for driving a tape loading lever, cassette loading gears 22, 22 and the like (not shown),
The loading motor 20 slides the loading lever to reciprocate the loading pins 3 and 4, and the loading motor 20 reverses the loading gears 22 and 22 to rotate the cassette holder 16
Is configured to reciprocate.

Further, as shown in FIG. 2, a wiring board 23 for forming a recording / reproducing circuit and a motor control circuit is provided below the deck chassis 1, and the board 23 is fixed to the lower surface of the chassis 1 with screws 24. At the same time, the light emitting diode 25, which is a light emitting body, and the phototransistors 26, 26, which are light receiving bodies, are directly attached and fixed to the substrate 23.

A central prism 27 made of acrylic resin in the shape of a quadrangular prism is provided, and the central prism 27 is attached to the chassis 1 by a hook 28 provided by insert molding.
And the lower end surface of the central prism 27 is disposed so as to face the light emitting diode 25, and left and right reflecting surfaces 29 and 30 are formed on the upper end portion of the central prism 27. The light from the light emitting diode 25 is configured to be emitted to both sides via the light.

Further, the left and right guide plates 17, 17 on both sides in the direction in which light is emitted from the central prism 27 are respectively provided with cylindrical bodies 31.
Is attached. As shown in FIG. 2, the tubular body 31 is composed of a reflecting plate 32 having a reflecting surface 32a that reflects the light from the light emitting element 25 toward the light receiving element 26, and a polystyrene resin that is an opaque member. A cylindrical main body 31A formed so as to hold 32 and cover the optical path from the vicinity of the reflection plate 32 side to the light receiving element 26 side in a U-shaped cross section, and one side end of the upper part of the cylindrical main body 31A. 31a is connected to the flexible connecting band 31b at two upper and lower positions,
The other side end 31c is provided with a lid 31B that can be locked by a hook 38 that is a locking portion.

A light guiding hole 31d for guiding light is provided at a position corresponding to the light emitting element 25 side of the lid 31B. Further, a metal film such as an aluminum foil is formed on the reflecting surface 32a so that the incident light is reflected to the light receiving element 26 side.

Next, the operation will be described. In the present invention, since the tubular body 31 is made of polystyrene resin which is an opaque member and covers the vicinity of the reflection plate 32 and the optical path of light from the vicinity of the reflection plate 32 to the light receiving element, the reflection plate 3
2 and the light path to the light receiving element 26 are blocked from external rays. Therefore, only the light from the light emitting element 25 is guided to the light receiving element 26. Therefore, the sensitivity of the light receiving element 26 is excellent, and no malfunction occurs. Further, it is possible to eliminate the conventional auxiliary printed circuit board and the lead wire between the auxiliary printed circuit board and the main printed circuit board.

Further, in the above-mentioned embodiment, as shown in FIG. 3, the position of the light receiving element 26 can be relatively changed by changing the angle of the reflecting surface 32a.

Next, an embodiment of the tape deck according to the second aspect of the present invention will be described with reference to FIGS. This embodiment relates to the structure of the above-mentioned tubular body 31, and the same components as those in the above-mentioned embodiment are designated by the same reference numerals. The tubular body 31 has a hook 38 which is a locking portion formed at a side end of a lid 31B connected to one side end 31a of an upper portion of the tubular main body 31A.
It is adapted to be inserted and locked in a locking hole 39 formed in the other side end 31c. In addition, the hook 38 and the locking hole 39
When separated from the cylinder main body 31A, as shown in FIGS.
The lid 31B and the lid 31B can be developed in a plane and can be manufactured as an injection molded product.

A convex portion 44 and a concave portion 46, which are in a fitting relationship, are formed on the inner periphery of the front surface portion 31e of the cylinder main body 31A and the corresponding portion of the cover plate 31B, and the cover plate 31B is connected to the connecting band. When the front portion 31e and the cover plate 31B are folded back from 31b and overlapped with each other, the above-mentioned fitting relationship can prevent a discrepancy between the two positions.

Therefore, after a reflective aluminum foil capable of reflecting light rays is formed on the reflective surface 32a by forming a metal film, the cover plate 31B is folded back from the connecting band 31b, and the cover plate 31B and the front surface portion 31e are projected. Due to the fitting relationship between the portion 44 and the recessed portion 46, the hooks 38 are overlapped with each other without shifting their positions, and the hooks 38 are engaged with the locking holes 39.
, And locks it, whereby the assembly of the tubular body 31 is completed.

In this cylindrical body 31, as shown in FIG. 7, the engaging projection 17b of the guide plate 17 provided on the reflection side is inserted into the light guide hole 31d.
The light receiving element 26 mounted on the main printed circuit board 23 is mounted on the main printed circuit board 23 by being inserted into the cylinder main portion 31A.

Since the cylindrical body 31 of this embodiment has the above-mentioned structure, the light emitting element 25 or its reflected light is guided by the light guiding hole 31.
The light enters the tubular body 31 from d, is reflected by the reflecting surface 32a, passes through the tubular main body 31A, and is received by the light receiving element 26, but becomes a space with respect to the wall surface of the U-shaped three faces. Since the surface that is closed can be closed by the side wall of the guide plate 17, external light rays cannot reach the inside of the tubular body 31, and the sensitivity of the light receiving element 26 is reduced and malfunction occurs as in the previous embodiment. Can be prevented.

Further, unlike the previous embodiment, the auxiliary printed circuit board and the wiring of the lead wire are not required, and since the tubular body 31 can be molded by an integral structure of injection molding, many moldings can be quickly performed by injection molding or the like. Therefore, the unit cost of parts can be significantly reduced, and the guide plate 17 can be easily attached to the side wall only by inserting it, and the assembly cost can be significantly reduced.

[0026]

As described above, according to the present invention as set forth in claim 1, by covering the periphery from the reflection surface of the tape deck to the light receiving element with the cylindrical body, the external light beam is applied to the light receiving element. It is possible to prevent the light rays from reaching the light receiving element and prevent the sensitivity of the light receiving element from deteriorating and malfunction due to the incident external light rays.

Further, compared with the case where the light receiving element is installed on the conventional auxiliary printed board provided in front of the light emitting element, it is necessary to wire the auxiliary printed board and lead wires from the main printed board to the auxiliary printed board. As a result, the number of assembling steps and the number of parts can be significantly reduced.

Further, according to the second aspect of the invention, the cylindrical body for blocking the external light rays to the light receiving element is formed by one molding part, and the manufacturing and assembling thereof is easy and easy, and the cylindrical shape is obtained. The cost of the body can be reduced, and the attachment can be performed easily, and the manufacturing and assembly costs can be significantly reduced.

[Brief description of drawings]

FIG. 1 is a plan view showing an embodiment of the tape deck of the present invention according to claim 1. FIG.

FIG. 2 is a cross-sectional view of a main part of the embodiment shown in FIG.

FIG. 3 is a cross-sectional view of a reflective tape portion of the embodiment shown in FIG.

FIG. 4 is a developed perspective view of an embodiment of the tape deck of the present invention according to claim 2;

5 is a developed plan view of the embodiment shown in FIG.

6 is a sectional view taken along line AA of the embodiment shown in FIG.

7 is a sectional view of the embodiment shown in FIG. 4 in a mounted state.

FIG. 8 is a schematic plan view of a conventional tape deck.

FIG. 9 is a side view of a conventional tape end detecting device.

FIG. 10 is a side view of another conventional tape end detection device.

[Explanation of symbols]

 25 light emitting element 26 light receiving element 31 tubular body 31A tubular main body 31B lid 31d light guide hole

Claims (2)

[Claims] 1. A tape deck provided with a light emitting element and a light receiving element for detecting the start and end of the tape, the reflector having a reflecting surface for reflecting the light from the light emitting element to the light receiving element side, and the reflector plate made of an opaque member. And a cylindrical body that holds the above and covers the vicinity of the reflection plate and the circumference of the optical path of the light to the light receiving element. 2. The tubular body is connected to a tubular main body having a U-shaped cross section that forms a portion from the side of the reflector holding the reflector to the side of the light receiving element, and to one side end of an upper portion of the tubular main body. A lid body having a light guide hole to the light emitting element and having a locking portion that can be engaged and disengaged at the other side end, and when the locking portion is separated from the other side end, the cylindrical main body and the lid are provided. A tape deck characterized by being able to be developed in a plane with the body.