JPH05242560A - Tape end detector - Google Patents

Abstract

PURPOSE:To improve the reliability of a tape end detection by reducing erroneous operations caused by an outside light, a reflection and refraction on a tape surface, etc. CONSTITUTION:While a tape pulling-out arm 11 is rotated around an arm axis 13 and a magnetic tape 10 is pulled out, a lever 4 is rotated by a lever driving projected part 14 provided on the tape pulling-out arm 11. As a loading end position is approached an optical sensor section 1 is risen and the magnetic tape is positioned on a wall surface opposed to the optical sensor section. A light emitting element and a light receiving element are each provided in a wall opposed to the optical sensor section 1 and in this condition, the optical sendor section is operated. Thus, a light from the light emitting element is made incident on the magnetic tape surface at a right angle and the light passing through the transparent part of the magnetic tape is detected by the opposing light receiving element.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a tape end detector,
In particular, the present invention relates to a tape end detector that is applied to a magnetic recording / reproducing apparatus and detects the beginning and end of a magnetic tape.

[0002]

2. Description of the Related Art Generally, transparent portions are provided on both ends of a magnetic tape so that the beginning and the end of the magnetic tape can be identified.

FIG. 2 shows an example of a conventional tape end detector, showing a state in which the magnetic tape 10 is loaded. Here, a light emitting portion 21 that emits light with a good directivity to the magnetic tape 10, a light receiving portion 22 that receives light from the light emitting portion 21 that has passed through the magnetic tape 10 and sends out an electrical signal, and a light emitting portion 21. And a fixed base 23 for fixing the light receiving unit 22.

Normally, the light emitted from the light emitting section 21 is the magnetic tape 1.
Although blocked by 0, light passes through the tape and is detected by the light receiving section 22 at the transparent portions provided at both ends of the magnetic tape.

Further, the shape of the fixing base 23 and the fixing positions of the light emitting portion 21 and the light receiving portion 22 are set so as not to obstruct the moving magnetic tape 10 when the tape is loaded.

[0006]

In the above-mentioned conventional tape end detector, the distance between the light emitting portion and the light receiving portion becomes long, and since the light is emitted obliquely to the magnetic tape, external light or However, there is a problem that malfunction occurs due to reflection, refraction, etc. on the tape surface.

An object of the present invention is to provide a tape end detector capable of reducing malfunctions due to external light, reflection and refraction on the tape surface, and improving reliability of tape end detection.

[0008]

The tape end detector of the present invention is a tape end detector for detecting a transparent portion of a tape in a state where the tape loading mechanism has loaded the tape. An optical sensor unit having light receiving elements and a moving unit for moving the optical sensor unit so that the tape is positioned between the opposing walls of the optical sensor unit when the tape loading mechanism has completed loading. It is configured.

[0009]

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

FIG. 1 is a diagram showing an embodiment of the present invention.
(A) is a perspective view and (b) is a side view. The solid line shows the state where the loading of the magnetic tape is completed, and the broken line shows the state before the loading of the magnetic tape is started.

Here, the tape end detector includes an optical sensor section 1 having a light emitting element and a light receiving element respectively in opposite walls, and the optical sensor section 1 is rotated about a rotation shaft 3 so that the optical sensor section 1 faces the magnetic tape 10. A sensor mount 2 that is moved along, a lever 4 provided on a rotary shaft for rotating the sensor mount 2, a fixed base 5 that rotatably holds the rotary shaft 3 of the sensor mount, and one end Is attached to the fixed base 5 and the other end thereof is attached to the sensor mounting base 2, and a return spring 6 for applying a rotational force in a fixed direction to the sensor mounting base is provided.

Next, the operation will be described.

Now, in the tape loading process,
The magnetic tape 10 is pulled out by the guide roller 12 provided at the tip of the tape pull-out arm 11. In this case, tape loading is performed by rotating the tape pull-out arm 11 around the arm shaft 13. On the other hand, the optical sensor unit 1 is at the position shown by the broken line by the return spring 6 before the start of the loading of the magnetic tape.

By the way, the tape pull-out arm 11 has
A lever driving protrusion 14 that engages with the lever 4 is provided, and the tape pull-out arm 11 rotates about the arm shaft 13, that is, in the process of loading the magnetic tape. It comes into contact with and rotates it.

Thereafter, the optical sensor unit 1 rises as it approaches the loading completion position, and the loading is completed in a state where the magnetic tape is positioned between the opposing wall surfaces of the optical sensor unit. By operating the optical sensor unit 1 in this state, the light from the light emitting element of the optical sensor unit 1 is incident on the magnetic tape surface at a right angle, and the light passing through the transparent portion of the magnetic tape is
It can be detected by the light receiving element facing.

When the magnetic tape is stored, the reverse operation is performed. That is, as the tape pull-out arm 11 rotates in the opposite direction about the arm shaft 13, the lever 4 rotates in the opposite direction by the restoring force of the return spring 6, and the optical sensor unit 1 moves. It falls without contact with.

When the optical sensor unit is moved, it is sufficient that the tape can be moved so as to be positioned between the opposing walls of the optical sensor unit in the loading completion state. Therefore,
It may be moved up and down or rotated, and may be moved after loading is completed.

[0018]

As described above, according to the present invention, the optical sensor portions each having the light emitting element and the light receiving element in the opposing walls are moved according to the loading state of the magnetic tape, and in the loading completion state, By moving the magnetic tape so that it is positioned between the opposing walls of the optical sensor, the light from the light emitting element can be incident on the surface of the magnetic tape at a right angle to detect the transparent portion of the tape. Since the distance to the element can be shortened, malfunctions due to external light, reflection on the tape surface, refraction on the tape surface, etc. can be reduced, and the reliability of tape end detection can be improved.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of the present invention, in which (a) is a perspective view and (b) is a side view.

FIG. 2 is a perspective view showing an example of a conventional tape end detector.

[Explanation of symbols]

 1 Optical Sensor Part 2 Sensor Mounting Base 3 Rotating Shaft 4 Lever 5 Fixing Base 6 Return Spring 10 Magnetic Tape 14 Lever Driving Protrusion

Claims (1)

[Claims] 1. A tape end detector for detecting a transparent portion of a tape in a state where the tape loading mechanism has loaded the tape, the optical sensor section having a light emitting element and a light receiving element on opposite walls, and the tape loading. A tape end detector, comprising: a moving unit that moves the optical sensor unit so that the tape is positioned between opposing walls of the optical sensor unit when the mechanism has completed loading.