JPS5818346Y2 - radio tuner - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an improvement of a stopper mechanism of a μ-tunable radio tuner.

This is a plan view showing the conventional μ-tuned radio tuner of FIG. 1, in which 1' is a frame, 2' is a coil holding plate hung inside the frame 1', and 3' is also a frame. A terminal plate is attached to the inside of the body 1' and is arranged parallel to the coil holding plate 2'.

Reference numeral 4' denotes a BC band coil held by the coil holding plate 2' and the terminal plate 3', and three coils are arranged side by side.

Although not shown in the drawing, there is an F on the back side of the coil 4'.
Three M-band coils are also provided.

5' is a printed wiring board incorporating components such as transistors, 6' is a shield case that covers the printed wiring board 5', and 7' is arranged between the terminal plate 3' and the front plate 1a' of the frame 1'. The provided guide rod 8' is a sliding portion that moves along the guide rod 7'.

A holding plate 10' that holds a ferrite core 9' that goes in and out of the coil 4' is attached to the slide part 8'.

11' is a rotating shaft having a threaded portion 11a'.

The rotating shaft 11' is rotatably supported by the coil holding plate 2' and the front plate 1a', and its threaded portion 11a' passes through the holding plate 10'.

Reference numeral 12' denotes a wire spring fitted into a groove in the threaded portion 11a' of the rotating shaft 11', and both ends of the wire spring are hooked to locking pieces 10a' provided on the holding plate 10'.

13' is a stopper provided on the rotating shaft 11'.

The stopper 13' is clearly shown in FIG.
Five stopper plates 13a'.

13b', 13c, 13d', 13e', and each stopper plate has protrusions 131a', 13lb', 1
31 c: 1. Connecting piece 132a with 31d', 131e';132b', 132c, 132d', 132
e' is provided.

Only the stopper plate 13a' rotates together with the rotating shaft 11', and the other stopper plates are loosely fitted onto the rotating shaft 11'.

In such a configuration, when the rotating shaft 11' is rotated, the wire spring 12' fitted to the threaded portion 11a' moves along the thread groove, so the holding plate 10' moves and the ferrite core 9' is coiled. 4' to perform tuning operation.

When the holding plate 10' approaches one of the extreme positions, the protrusion of each stopper plate abuts the adjacent coupling piece, and the rotation of the rotating shaft 11' is stopped.

By the way, the structure of the stopper 13' as described above is suitable as a stopper for this type of tuner because it can stop the rotation after the rotating shaft has been rotated a plurality of times in any direction.

However, some users forcefully rotate the rotating shaft even after the rotating shaft reaches one of the extreme positions.

For this reason, the protrusion of the stopper often gets over the connecting piece of the stopper plate, and the stopper is often destroyed.

In addition to the above-described stopper structure, for example, a stopper is provided in which a locking piece is provided on the slide @8' and the locking piece is brought into contact with a stopper piece provided on the frame 1 to stop the rotation of the rotating shaft. There is also a structure 4, but this structure also causes failures such as damage to the locking piece if the rotating shaft whose rotation has been stopped is forced to rotate.

The purpose of the present invention is to create a structure in which the tuner structure will not be destroyed even if the rotary shaft reaches its limit position and is further rotated for a μ tuning type tuner that performs tuning operation by rotating the rotary shaft multiple times. The purpose is to provide and improve the conventional shortcomings.

Next, one embodiment of the present invention will be described in detail using the drawings.

FIG. 3 is a plan view of the μ-tunable radio tuner according to the present invention.

In the figure, 1 is a frame formed by pressing a metal plate, which includes a front plate 1a and a side plate 1b.

It has an Ic1 bottom plate 1b.

2 is a coil holding plate provided almost at the center of the frame 1 like a partition plate.

Reference numeral 3 denotes a threaded rod rotatably supported by the front side plate 1a and the coil holding plate 2, and a gear 3a is attached to one end.

Reference numeral 4 denotes a setter screwed onto the screw shank 3, which moves in the longitudinal direction as the screw shank 3 rotates.

As shown in FIGS. 4 to 6, the setter 4 has a main body 4a.
It has a protruding contact part 4b at the upper part, and a screw receiver part 4b at the lower part.
It has c.

A guide leg 4d protrudes below the screw receiver portion 4c to prevent the setter 4 from rotating when the screw stud 3 rotates by contacting the bottom plate 1b of the frame body 1.

Elastic parts 4e and 4f extend downward from the main body 4a and clamp the threaded rod 3 at their tips, and have a tapered portion 4g as is clear in FIG.

4h is a threaded portion provided on the main body 4a.

Returning to FIG. 3, reference numeral 5 denotes a main shaft, which is rotatably supported by the front plate 1a, and a gear 5a provided on the main shaft 5 meshes with a gear 3a attached to the screw barrel 3.

6 is a guide rod provided near the side plate 1b of the frame and parallel to this; 7 is a slide portion that moves along the guide rod 6;
The side portion has a stopper piece 7a that moves within a groove 1e provided in the side plate 1b.

The slide part 7 includes a holding plate 1 that holds a ferrite core 9 that goes in and out of the coil 8 attached to the coil holding plate 2.
0 is attached.

A compression spring 11 is wound around the guide rod 6 and biases the slide portion 7 toward the front plate 1a.

12 is a terminal plate attached to the front end of the coil 8.

Next, the operation of the present invention will be explained.

As shown in FIG. 7, when the setter 4 is stopped in the middle of the screw formation 3, as shown in FIG.
The holding plate 10 comes into contact with the contact portion 4b of the setter 4 and presses it in the direction of the arrow by the force of the compression spring 11.

Since the elastic parts 4e and 4f of the setter 4 hold the threaded part 3, the threaded part 4h engages with the thread of the threaded part 3, and the end part 4h-1 in particular is strongly pressed against the threaded rod 3, and The portion 4c of the receiver is in contact with the threaded rod 3.

When the main shaft 5 is rotated in one direction from this state, the rotation is transmitted from the gear 5a to the screw barrel 3 via the gear 3a.
Rotate the threaded rod 3.

When the screw shank 3 rotates, the setter 4 screwed onto the shank 3 moves along the screw rod 3 to the front plate without rotating because its guide foot 4d is in contact with the bottom plate 1d of the frame 1. 1
Move in direction a.

When the setter 4 moves, the slide part 7 moves under the pressure of the compression spring 11, so the holding plate 10 follows the setter 4 and moves, and the ferrite core 9 held by it is pulled out from the coil 8. Continuously shifts the tuning frequency from lower to higher.

When the main shaft 5 is rotated even after the stopper piece 1a of the slide portion 7 hits the end of the groove 1e of the side plate 1b, the upper end (protrusion) of the tapered portion 4g of the setter 4 comes into contact with the front side plate 1a. .

Since the upper end of the tapered portion 4g is deviated above the axis of the threaded rod 3, if the main shaft 5 is still rotated even after the upper end of the tapered portion 4g contacts the front plate 1a, the setter 4 As shown in FIG. 8, it rotates in the direction of the arrow, and the entire surface of the tapered portion 4g comes into contact with the front plate 1a.

At this time, the elastic parts 4e and 4f are slightly expanded.

For this reason, the threaded portion 4h of the setter 4 rises, and the threaded rod 3
This state is maintained even if the threaded rod 3 is rotated thereafter, and the threaded rod 3 rotates idly.

When the rotation of the main shaft 5 is stopped, the setter 4 is rotated in the direction opposite to the arrow shown in FIG. 8 due to the elastic force of the elastic parts 4e and 4f, and the setter 4 is screwed into the threaded part 4h with the spring screw barrel 3.

Next, when the rotating shaft is rotated in the opposite direction, the setter 4 begins to move in the direction of the coil holding plate 2.

This setter 4 presses and moves the holding plate 10,
The ferrite core 9 is gradually inserted into the coil, and the tuning frequency is continuously shifted from high to low.

When the setter 4 continues to move by rotating the main shaft 50 times, the coil holding plate 2
The screw receiver provided on the setter 4 protruding in the direction is the part 4c.
The tip 4cm1 (protrusion) contacts the coil holding plate 2.

If the main shaft 5 continues to rotate thereafter, the tip end 4e-1 is deviated below the axis of the threaded rod 3, so the setter 4 rotates in the direction of the arrow as shown in FIG.

At this time, the elastic parts 4e and 4f are slightly expanded.

For this reason, the threaded portion 4h of the setter 4 rises, and the threaded rod 3
The mesh becomes disengaged.

When the setter 4 and the threaded rod 3 are disengaged, the setter 4 is pushed by the retaining plate 10 biased toward the front plate 1a by the compression spring 11 and returns slightly toward the front plate 1a, so that the setter 4 moves to the elastic portion 4c. and the 9th elastic force of 4f.
It rotates a little in the direction opposite to the arrow direction shown in the figure, and the threaded portion 4h engages with the spring threaded rod 3 again.

In particular, when the main shaft 5 continues to rotate, the tip 4cm1 of the threaded part 4c of the setter 4 comes into contact with the coil holding plate 2 again, and as mentioned above, the threaded rod 3 and the threaded part 4h of the setter 4 disengage, and the screw The rod 3 repeats the action of spinning idly.

As explained in detail above, according to the present invention, when the operating shaft of the tuner is rotated and reaches one of the extreme positions, the setter is rotated slightly (tilting) in the axial direction of the threaded rod.
At least disengage the threaded part of the setter and the threaded rod, so
Screw money goes around.

Therefore, even if the dial of the radio is forcibly rotated after it reaches one end, the tuner will not be damaged in any way because the knob simply rotates.

Furthermore, when the threaded rod idles, the threaded portion of the setter and the screw of the threaded rod are completely unthreaded, so the threaded portion of the setter will not be damaged when the screw line idles.

For this reason, the thread engagement accuracy between the setter and threaded rod can be maintained over a long period of time, which not only greatly reduces the possibility of deterioration in the degree of adjustment due to wear and tear on the setter screw, but also prevents the stopper strength from being guaranteed as in the past. The diameter of the main shaft and threaded rod can be made thinner because a mechanism for this purpose is not required and there is no need to apply excessive force to the drive system such as the main shaft.

In addition, since the main shaft of the drive system is an Oldham gear,
No need for expensive milled shafts as in the past,
The drive system can be standardized, and the old drive system is now an Oldham gear, so the depth of the drive system can be significantly shortened.
In addition to contributing to the miniaturization of tuners, it also makes it easier to design the drive system gear structure when creating models with different drive system gear ratios.

In addition, when the knob □ reaches one of the extreme positions and the setter comes off the threaded rod, a light click is produced, so you can intuitively know that the ultimate position has been reached. It is.

[Brief explanation of the drawing]

Fig. 1 is a plan view of the conventional device, Fig. 2 is an exploded perspective view showing the stopper mechanism of the conventional device, Fig. 3 is a plan view showing an embodiment of the present invention, and Figs. 4 and 5 are of the setter. FIG. 6 is a perspective view, FIG. 6 is a sectional view of the setter, and FIGS. 7 to 9 are sectional views of the setter for explaining the operation. In the figure, 1 is a frame body, 1a is a front side plate, 1b and 1c are side plates,
1d is the bottom plate, 2 is the coil holding plate, 3 is the spring screw rod, 3a is the gear, 4 is the setter, 4a is the main body, 4b is the contact part, 4c is the spring screw receiver part, 4d is the guide foot, 4e and 4f are the elastic parts ,
4g is a taper part, 4h is a spring screw, 5 is a main shaft, 6 is a guide rod, 7 is a slide mechanism, 8 is a coil, 9 is a ferrite core, 10 is a holding plate, 11 is a compression spring, 12 is a terminal plate. .

Claims (1)

[Scope of utility model registration request] A holding plate that holds one end of the ferrite core that can be moved in and out of the coil, a stop mechanism that stops the holding plate at an extreme position in the direction in which the ferrite core moves in and out, a threaded rod that is rotated during a channel selection operation, and a screw. a setter that is screwed onto the rod and moves by the rotation of the rod; a spring member that constantly presses the retainer plate against the setter in order to interlock the retainer plate with the movement of the setter; and a spring member formed integrally with the setter;
a threaded portion that is threaded into a circumferential portion of the threaded rod; an elastic portion that is formed integrally with the setter and acts to press the threaded portion against the threaded rod; and an elastic portion that is formed integrally with the setter. , a protrusion that rotates the retaining plate at the extreme position where it comes into contact with the frame of the tuner and rotates the setter a small amount with respect to its traveling direction, and rotates the threaded rod to bring the setter to the extreme position A stopper mechanism for a μ-tuned radio tuner, characterized in that when the setter reaches the setter, the setter is slightly rotated in the direction of travel, and the threaded rod is unscrewed from the threaded part of the setter, causing the threaded rod to rotate idly.