JPS6318193Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to muting of inter-station noise when changing the receiving station using a preset push button in car radios equipped with FM receivers, which have been increasing in recent years.

Conventionally, some car radios with a preset push button have an automatic frequency control circuit turned off when selecting a channel, and a switch is interlocked with a push button tuner in order to ensure reliable channel selection. Although this is effective for reliable tuning, another problem with car radios equipped with preset buttons is the muting of inter-station noise. That is, in a situation where the position is constantly changing due to running, if the muting to prevent inter-station noise is activated sufficiently, stations with weak input cannot be received, so it is normal that the muting is not activated. However, when switching the receiving station from station A to station B using a preset push button in such a receiver, a momentary but quite intense inter-station noise is heard.

The present invention is an improvement on the above-mentioned points, and the tuner frame 1 includes a plurality of levers 2a, 2b, 2c... each having a push button 2, 2, 2... at its tip, and a preset tuning mechanism 5 having a known structure. Each lever has a protrusion 3a, 3b, 3c, . . . on its side surface. The protrusions are located at the rotating ends 4a, 4 of the comb-shaped rotating plate 4.
b, 4c... respectively, and rotates the rotating plate 4 when each lever is pressed. The rotating plate 4 is pivotally supported by the side surface of the frame 1, and is biased by a spring 6 in the abutting direction. One end 7 of the rotating end of the rotating plate 4 is connected to a mechanism 8 that temporarily disconnects the manual tuning operation mechanism when a button is pressed. This mechanism is well known and will not be described in detail. For example, in a mechanism in which the rotational force of the manual operation knob 12 is transmitted to the synchronization mechanism 5 by constantly pressing the clutch 10 with the spring 9, when the push button is pressed, The rotating end 7 of the rotating rotating plate 4
This mechanism disconnects the clutch 10 by rotating the seesaw-shaped lever 11 against the biasing force of the spring 9 and separating the clutch 10.

By the rotating end 7 or the rotating end of the lever 11,
The actuator 13a of the switch 13 is placed at a position where it should be pressed during rotation. Therefore, the intermediate frequency amplification section 16 or the low frequency amplification section 17 of the radio receiver 15
An opening/closing circuit using this switch is connected to a muting circuit 14 for applying muting to the signal.

With this configuration, when an FM broadcast listener wants to change the receiving station and presses one of the plurality of push buttons 2, the lever 2a moves forward, and the protrusion 3a moves toward the pivot end 4a of the pivot plate 4. Press the rotating plate 4
The rotating end 7 presses the actuator 13a of the switch 13, and the muting circuit 1
4, so inter-office noise will not be heard while the button is pressed. When the receiving station switching is completed and the push button is released, each member returns to its original state by the action of the spring described above.

As described above, according to the present invention, one tuning mechanism has a manual tuning operation section in addition to a preset tuning operation section using a push button, and when the push button is pressed, the manual operation section and the tuning mechanism are connected. In the device equipped with a mechanism for disconnecting the connection, a switch is provided which is operated by a member that operates the mechanism for disconnecting the connection, and mutating is performed by the switch when the push button is pressed. By simply adding a muting switch to the tuner, it is possible to prevent inter-station noise when switching receiving stations, and it has a great practical effect when used in a vehicle-mounted FM receiver.

[Brief explanation of the drawing]

The drawing shows an embodiment of the present invention, and the drawing shows a plan view of a push-button tuner, and in the figure, 2a, 2b, 2c...lever as a preset tuning operation part, {4...rotating plate} a mechanism for breaking the connection. member for operating, 5... tuning mechanism, 8...
...a mechanism for breaking the connection, 12...a knob serving as a manual tuning operation section, {13}...a switch, and 14...a muting circuit.

Claims (1)

[Scope of utility model registration request] For one tuning mechanism, there is a tuning operation section that operates in two systems, a push button and a manual operation section, and a projection is formed on the side of the lever of the push button, and the projection is routed to the side plate of the frame of the tuning mechanism. The rotating end of the movably supported rotating plate is always in contact with the rotating end, and at one end of the rotating plate, when a push button is pressed, the clutch is separated to cut off communication between the manual operating section and the tuning mechanism. An inter-station noise muting mechanism for a push button adjuster, in which a lever is always in contact with the lever, and the switch is actuated by the operation of the lever when the push button is pressed to perform muting.