JPH0313875Y2 - - Google Patents

Description

[Detailed explanation of the invention] (a) Industrial application field The present invention is used in tape recorders, video decks, etc., and is a detection switch for preventing accidental erasure, which detects the accidental erasure prevention strip provided on the back of the cassette. Regarding.

(B) Prior Art Conventionally, a switch for detecting a piece to prevent accidental erasure of a cassette used in tape recorders, video decks, etc. has a V-shaped cross section at the tip, for example, as shown in Figures 1 and 2. An operating side contact piece d and a receiving side contact piece f having a protrusion e are fixed to the body a at a predetermined interval. The body a is integrally molded with an outer frame b provided with a hollow portion C. A protruding portion e of the operating side contact piece d protrudes to the outside from the hollow portion C of the outer frame b.

In this operation, if the cassette has a piece to prevent accidental erasure, after the cassette is inserted, the piece pushes up the protrusion e of the contact piece d on the operating side so that both pieces come into contact with each other. If not,
After the cassette was inserted, the projecting portion e of the operating side contact piece d entered the hole remaining after the prevention piece was removed, so that the two contact pieces did not come into contact with each other.

However, in the above switch, since the position of the operating point where the operating side contact piece d and the receiving side contact piece f come into contact is fixed, the position of the protrusion e of the operating side contact piece d is lower than the surface of the cassette tape. If they are moved apart, even if there is a piece to prevent accidental erasure, both contact pieces cannot be brought into contact, and if they are moved close to the surface of the cassette, the protruding piece e of the operating side contact piece d will not be able to make contact. Both contact pieces came into contact with the bottom of the remaining hole in the cassette from which the prevention piece had been removed, pushing up the operating side contact piece d, and this contact sometimes caused the false erasure prevention piece to be detected incorrectly.

Therefore, even in the manufacturing process of tape recorders, video decks, etc., the permissible range of operating points is narrow, so precision in the mounting position relative to the cassette is required. Therefore, it has to be installed by a skilled person while making adjustments, which has the drawback of requiring time and effort.

(C) Purpose The present invention provides a cassette cassette erroneous erasure prevention piece detection switch that can detect the cassette erroneous erasure prevention piece without any error, even though it does not require fine adjustment of the mounting position of the switch. is intended to provide.

(d) Configuration: an operating side contact piece and a receiving side contact piece made of an elastic body, a body which arranges both the contact pieces at a predetermined interval and fixes the base ends of both the contact pieces, and a body with a base end attached to the body. A protruding portion having a V-shaped cross section is formed at the tip of the operating side contact piece, and the operating side contact piece and the receiving side contact piece are connected to each other in the guide frame. Two locking parts are provided to keep the distance between the two contact pieces constant regardless of the displacement of the guide frame, and a sliding part is provided at the tip of the guide frame to make the protrusion project slightly larger than the predetermined distance between the contact pieces. A contact surface is provided, and when the protrusion comes into contact with the accidental erasure prevention piece of the cassette, the operating side contact piece deforms using one of the locking parts as a fulcrum and contacts the receiving side contact piece. It is characterized by

(E) Embodiment FIG. 3 is a perspective view showing an embodiment of the piece detection switch for preventing accidental erasure of a cassette according to the present invention, FIG. 4 is a longitudinal sectional view of FIG. 3, and FIG. 5 is a cassette according to the present invention. FIG. 3 is an explanatory diagram showing the operating state of the piece detection switch for preventing erroneous erasure.

Reference numeral 1 denotes a body, in which the base ends of the operating side contact piece 3 and the receiving side contact piece 4 are fixed at a predetermined interval. A protrusion 13 having a V-shaped cross section is formed at the tip of the operating side contact piece 3. Only the wide dimension stands out.

The guide frame 2 is a substantially T-shaped frame body, and an inclined sliding surface 7 is formed at the tip thereof.

The guide frame 2 has its base end connected to both side walls of the body 1 via a support shaft 12 so as to be swingable. The guide frame 2 is provided with locking portions 5, 5', and the operating side contact piece 3 and the receiving side contact piece 4 are locked on the locking portions 5, 5'. The frame 2 is resiliently biased downward in the figure by each of the contact pieces. Note that 6 is a stopper that prevents rotation of the guide frame at a predetermined position.

Furthermore, the locking portions 5, 5' prevent the operating side contact piece 3 and the receiving side contact piece 4 from coming into contact unless pressure is applied to the protruding portion 13 of the operating side contact piece 3 even if the guide frame 2 is displaced. The predetermined interval is maintained unchanged.

As described above, the piece detection switch for preventing erroneous erasure of the present invention is configured so that the operating point where the operating side contact piece 3 and the receiving side contact piece 4 come into contact is constant with respect to the guide frame 2.

Therefore, even if the cassette 8 is inserted with the detection switch out of position, the sliding surface 9 of the cassette will slide against the sliding surface 7 of the guide frame 2 and push up, causing the guide frame 2 to It must be in sliding contact with the surface of the cassette.

Therefore, the operating point is also displaced together with the guide frame 2 pushed up by the sliding surface 9 of the cassette.

Next, specifically, the cassette's accidental erasure prevention piece 9
A case will be explained in which the detection switch is in a misaligned position.

As the cassette 8 is inserted, the sliding surface 9 of the cassette pushes up the sloped sliding surface 7 and pushes the support shaft 1 upward.
2 as a fulcrum, but a predetermined distance between the operating side contact piece 3 and the receiving side contact piece 4 is maintained by the locking portions 5 and 5'. When the cassette 8 is subsequently inserted, the protrusion 13 of the operating side contact piece 3 is pushed up by the piece for preventing accidental erasure, and the operating side contact piece 3 and the receiving side contact piece 4 come into contact (as shown by the solid line in Fig. 5). ).

The same operation occurs when the detection switch is in the correct position.

Next, a case will be described in which the cassette does not have the mistaken erasure prevention piece 10 and the detection switch is in a shifted position.

As the cassette 8 is inserted, the sliding surface 9 of the cassette pushes up the sloped sliding surface 7 and pushes the support shaft 1 upward.
2 as a fulcrum, but since the protrusion 13 of the operating side contact piece 3 enters the remaining hole 11 from which the piece 10 for preventing accidental erasure was removed, the operating side contact piece 3 and the receiving side contact piece 4
(shown by the dashed line in FIG. 5).

A similar operation occurs when the detection switch is in an appropriate position.

As described above, the presence or absence of the erroneous erasure prevention piece can be detected based on the presence or absence of contact between the operating side contact piece 3 and the receiving side contact piece 4. Furthermore, since the sliding surface 7 is formed into a sloped shape, there is an advantage that the sliding surface 7 contacts the sliding surface 9 of the cassette smoothly.

In the above-described embodiment, the body 1 and the guide frame 2 are connected by the support shaft 12, but the present invention is not limited to this, and the body 1 and the guide frame 2 can be freely connected using an elastic body. The point is that the body 1 and the guide frame 2 can be connected in a swingable manner.

(f) Effects Conventional detection switches detect the accidental erasure prevention piece when the operating point is fixed, but if the detection switch is misaligned with respect to the surface of the cassette, it cannot be detected accurately. .

However, the inventive cassette chip detection switch for preventing accidental erasure does not require delicate position adjustments because its configuration moves the operating point of each contact to the optimal position relative to the cassette surface. ,and,
The erroneous erasure prevention piece can be detected without error.

Therefore, in the production process of tape recorders, video decks, etc., by using the single detection switch for preventing accidental erasure of the present invention, there is no need to make fine adjustments to the mounting position of the detection switch, which conventionally took time and effort. be.

Therefore, since it can be easily installed by anyone, an improvement in production efficiency can be expected.

Although the present invention is a piece detection switch for preventing erroneous erasing of a cassette, it is not limited to this and can be applied to other electrical appliances as a recess detection switch.

[Brief explanation of drawings]

FIG. 1 is a conventional perspective view, FIG. 2 is a vertical sectional view of FIG. FIG. 3 is a vertical cross-sectional view, and FIG. 5 is an explanatory view showing the operating state of the piece detection switch for preventing erroneous erasure of a cassette according to the present invention. 1... Body, 2... Guide frame, 3... Operating side contact piece, 4... Receiving side contact piece, 5, 5'... Locking part, 7
... Sliding surface, 10 ... Erroneous erasure prevention piece, 13 ...
protrusion.

Claims (1)

[Scope of utility model registration request] Operating side contact piece 3 and receiving side contact piece 4 made of an elastic body
and a body 1 which arranges both the contact pieces 3 and 4 at a predetermined interval and fixes the base ends of both the contact pieces 3 and 4.
and a guide frame 2 whose base end is connected to the body 1.
A protrusion 13 having a V-shaped cross section is formed at the tip of the operating side contact piece 3, and the operating side contact piece 3 and the receiving side contact piece 4 are provided in the guide frame 2.
Two locking parts 5, 5' are provided to keep the distance between the guide frame 2 constant regardless of the displacement of the guide frame 2. A sliding contact surface 7 is provided that protrudes slightly larger than a predetermined interval between the two, and when the protruding portion 13 comes into contact with the accidental erasure prevention piece 10 of the cassette 8, the operating side contact piece 3 touches the locking portion. A piece detection switch for preventing erroneous erasure of a cassette, characterized in that it deforms using one of the parts 5 as a fulcrum and comes into contact with a receiving contact piece.