JPH0210580Y2 - - Google Patents

Description

[Detailed description of the invention] This invention is a cassette tape that detects the holes for tightening screws in the cassette half of the cassette tape or the recesses provided in a part of the cassette half for distinguishing between the front and back sides. This invention relates to a front/back detection switch.

In an auto-reverse type cassette tape recorder, it is necessary to detect in advance the front and back sides of the inserted cassette half to regulate the tape running direction.

To achieve this purpose, holes for cassette half tightening screws, which are conventionally provided only on one side of the cassette tape and not on the other side, or holes for asymmetrical front and back sides provided in a part of the cassette half for front and back detection. It has been proposed to detect the recessed portion with a detection switch provided in a part of the chassis to determine whether the recessed portion is front or back.

However, with such a detection mechanism, detection is impossible unless the cassette tape is completely installed in the cassette tape recorder.

In addition, in a cassette tape recorder in which a cassette tape is inserted in advance into a movable holder that also serves as a lid of the cassette mounting section and rotated to facilitate mounting, a detection switch is attached to the movable holder, and a detection switch is attached to the movable holder. If you try to detect the front and back sides of the cassette tape before it is completely inserted, the tip of the detection switch may get stuck when inserting the cassette tape, which may prevent insertion and cause problems such as damage to the detection switch.

Therefore, in this case, it is necessary to retract the detection switch out of the cassette tape path when the cassette tape is inserted into the movable holder, and release the retraction when the insertion of the cassette tape into the movable holder is completed, which complicates the mechanism. Due to the risk of failure, a detection mechanism with a simple structure was desired.

This idea was made in view of the above points, and the movable contact piece is actuated by the displacement of the detection part that can be fitted into the hole for the cassette half tightening screw of the cassette tape or the recess provided for distinguishing front and back sides. A front/reverse detection switch is provided on the movable holder of the cassette tape recorder, and the detection part is made into a sphere and has a small through hole with a diameter slightly smaller than that of the holder. By pressing the member with the elasticity of the movable contact piece and causing a part of the sphere to protrude from the small through hole toward the cassette tape insertion part, the detection time of the front and back sides of the cassette tape is accelerated, and the cassette tape At the time of insertion, the spherical detection part rotates freely and the insertion is not obstructed, thereby solving the conventional drawbacks.

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

In FIGS. 1 and 2, the lower edge of a movable holder (hereinafter simply referred to as "holder") 3, which incorporates a lid 3a of a cassette tape mounting section, is pivotally attached to a cassette tape recorder main body 1 by a shaft 2. A notch 3b is provided in a part of the holder 3, a holding fitting 4 as a holding member is fixed to this notch 3b so that it is flush with the back surface of the lid 3a, and a small through hole 4a is formed in this holding fitting 4. establish.

Next, a movable contact piece 5a,
Fixing the base of the detection switch 5, which is a leaf switch having first and second fixed contact pieces 5b and 5c,
The movable contact piece 5a is brought into contact with the fixed contact piece 5b by its own elastic biasing force.

Furthermore, a sphere 6 having a slightly larger diameter than the small through hole 4a of the holding fitting 4 is pressed in the direction of the holding fitting 4 with the tip of the movable contact piece 5a, and held with a part of the sphere 6 protruding from the small through hole 4a. do.

In FIG. 1, 7 is a head stand, and 8 is a magnetic head.

On the other hand, the Philips standard cassette tape 10 inserted into the movable holder 3 has a hole 10a on one side for inserting the head of the cassette half tightening screw 11.
This hole 10a does not exist on the other side. In particular, the recess in the longitudinal center of the cassette tape 10 near the tape running surface has a considerable depth and can be effectively used for detecting the front and back sides of the cassette tape.

The above-mentioned sphere 6 is provided at a position where it can face the hole 10a when the cassette tape 10 is inserted into the holder 3, and constitutes the detection section of the detection switch 5. When the hole 10a is on the spherical body 6 side, as shown in FIGS. 1 and 2, when the cassette tape is inserted, the spherical body 6 is pressed by the pressing member 5d provided at the tip of the movable contact piece 5a, and the spherical body 6 is pushed into the hole. 10a, the movable contact piece 5a is brought into contact with the first fixed contact piece 5a.

Also, when the hole 10a is on the opposite side from the sphere 6,
When the cassette tape is inserted, the sphere 6 is attached to the holding metal fitting 4.
The movable contact piece 5a is bent against its own elastic biasing force and brought into contact with the second fixed contact piece 5c.

When the cassette tape 10 is inserted into and removed from the holder 3, the sphere 6 retreats into the holding fitting 4 and rotates freely, so that insertion and removal can be carried out extremely smoothly without getting stuck.

Next, Fig. 3 shows an embodiment of this invention in which a cassette tape having a separate recess for distinguishing front and back sides is used in a part of the cassette half instead of using the hole for the cassette half tightening screw. It is something.

In this embodiment, a recess 20a is provided at the center of the side surface of the cassette half on one short side of the cassette tape 20, and a sphere 6 that can be fitted into the recess 20a is inserted into the detection switch provided on the movable holder 3. The cassette tape 20 is attached to the movable contact piece 5a of 5.
Press to the side.

In this case as well, place the cassette tape 20 in the movable holder 3.
When the concave part 20a is on the sphere 6 side, the movable contact piece 5a contacts and conducts with the first fixed contact piece 5b, and when the cassette tape 20 is turned over, the concave part 20a is on the sphere 6 side. Instead of facing the second fixed contact piece 5c, the sphere 6 is pushed in and the movable contact piece 5a contacts and conducts with the second fixed contact piece 5c.

In the above embodiment, the elastic biasing force of the movable contact piece 5a is used to press the sphere 6 toward the cassette tape insertion section, so the number of parts can be reduced; An elastic member for pressing the sphere 6 against its holding member may be provided separately from the contact piece 5a. In addition, although a three-contact switching type leaf switch was used in the embodiment, a two-contact switching type leaf switch may also be used, or even if it is not a leaf switch, the contacts can be opened/closed or turned off by the displacement of the detection part by the sphere 6. Any switch may be used as long as it can be replaced.

Further, in the above embodiment, the present invention was applied to a vertical cassette tape recorder, but it can also be applied to a horizontal type cassette tape recorder. In this case, depending on the model, the direction of the cassette tape may be reversed when it is inserted, but such a case can be dealt with simply by changing the position of the detection switch.

Furthermore, since this detection switch has extremely low operating resistance when sliding, it can be applied to other switches, such as a pack-in switch that determines whether or not a cassette tape has been inserted, with great effect. .

As described above in the embodiment, the switch for detecting the front and back sides of a cassette tape according to this invention is provided in the movable holder of the cassette tape recorder, so that the front and back sides of the cassette tape are immediately detected when the cassette tape is inserted into the movable holder. Moreover, since the sensing part is spherical and can fit into the hole for the tightening screw in the cassette half or the recess for distinguishing between front and back sides, there is no risk of it interfering with inserting or removing the cassette tape or damaging it. do not have.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of the main part showing an embodiment of this invention, FIG. 2 is an enlarged sectional view of the detection switch part,
FIG. 3 is a partially sectional front view showing another embodiment of this invention. 1...Cassette tape recorder main body, 3...Movable holder, 4...Holding metal fittings (holding member), 5...
Detection switch, 6... Sphere, 10, 20... Cassette tape, 10a... Hole, 11... Screw for tightening cassette half, 20a... Recessed part for distinguishing front and back.

Claims (1)

[Scope of Claim for Utility Model Registration] A hole provided in a movable holder of a cassette tape recorder for a cassette half tightening screw of a cassette tape inserted into the movable holder, or provided in a part of the cassette half for distinguishing front and back sides. A switch for detecting the front and back sides of a cassette tape, which has a detection part that can be fitted into a recess, and a movable contact piece is actuated by displacement of the detection part to open/close or switch a contact point with a fixed contact piece. The detection part is made into a sphere, and the elasticity of the movable contact piece is used to press against a holding member having a small through hole with a diameter slightly smaller than the diameter of the sensing part, and one part of the sphere is pushed from the small through hole toward the cassette tape insertion part. A switch for detecting the front and back sides of a cassette tape, characterized by a protruding section.