JPH0818400A - Gear device - Google Patents

Abstract

PURPOSE:To prevent teeth of a gear from being skipped when the gear stops. CONSTITUTION:A stopper 21 is provided above a pinion 16 and engagement grooves 23A and 23B are provided on both its flanks. On the top surface of a tuning gear 14 meshing with the pinion 16, engagement pins 24A and 28 which can abut against the bottom surfaces of the engagement grooves 23A and 23B are provided. When a tuning knob 15 is rotated counterclockwise, the bottom surface of the engagement groove 23A abuts on the engagement pin 24A. Then the engagement grooves 23A and engagement pins 24A mutually restrict their positions and the pinion 16 is disabled to rotate counterclockwise any more. Therefore, even when a counterclockwise turning force is applied to the tuning knob 15, the teeth of the pinion 16 never skips over the teeth of the tuning gear 14. When the tuning knob 15 is rotated clockwise, the same effect as above is obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gear device suitable for application to a tuning device or the like.

[0002]

2. Description of the Related Art In a radio tuning device 1 as shown in FIG. 6, for example, a variable capacitor (variable capacitor) 12 is attached to a substrate 11, and a tuning gear 14 is fixed to a rotary shaft 13 thereof. On the other hand, a tuning knob 15 is rotatably attached to the substrate 11, and a pinion 16 that meshes with the tuning gear 14 is provided in the middle of the tuning knob 15. Tuning knob 15 is the cabinet 1
It is exposed to the outside from 7.

Further, as shown in FIG. 7, a rack 18 is engaged with the pinion 16 of the tuning knob 15, and a tuning pointer 20 for pointing the reception frequency of the variable condenser 12 displayed on the display unit 19 is provided at the tip of the rack 18. ing. Now, when you turn the tuning knob 15, the pinion 1
The rotary shaft 13 of the variable condenser 12 is rotated via 6 and the tuning gear 14. As a result, the capacitance of the variable capacitor 12 changes and the reception frequency changes. That is, it becomes possible to select an arbitrary program.

[0004]

By the way, in the conventional tuning device 1, the rotary shaft 13 of the variable condenser 12 is provided.
Is designed to rotate by a predetermined angle.
When 3 is stopped, the tuning knob 15 is also stopped. That is, the variable condenser 12 serves as a stopper for the tuning knob 15.

Therefore, when the tuning knob 15 is stopped and a force for forcibly turning the tuning knob 15 acts, the teeth of the pinion 16 may jump over the teeth of the stopped tuning gear 14 and the pinion 16 may rotate. is there. Then, the rack 18 meshed with the pinion 16 slides, and there is a problem that a reception frequency indicated by the tuning pointer 20 and a frequency actually received by the variable condenser 12 are displaced.

In order to avoid such a problem, a method may be considered in which the tuning pointer 20 is stopped by applying it to a stopper (not shown) at the movement limit position of the tuning pointer 20, but in this case, the tuning pointer 20
Therefore, the tuning pointer 20 becomes thick, which is not desirable in appearance.

Therefore, the present invention solves the above-mentioned problems and proposes a gear device which can easily prevent gear jump.

[0008]

In order to solve the above-mentioned problems, in the present invention, in a gear device in which a pair of meshing gears are stopped at a predetermined rotation position, a pair of gears has a predetermined rotation position. It is characterized in that a locking means for locking is provided.

[0009]

As shown in FIGS. 1 and 2, a stopper 21 is provided on the upper side of the pinion 16, and semicircular locking grooves 23A and 23B are provided on both side surfaces thereof. On the other hand, on the upper surface of the tuning gear 14 meshed with the pinion 16, the locking pin 2 that can come into contact with the bottom surfaces of the locking grooves 23A and 23B.
4A and 24B are provided.

Now, when the tuning knob 15 is turned counterclockwise, the bottom surface of the locking groove 23A comes into contact with the locking pin 24A as shown in FIG. As a result, the locking groove 23A and the locking pin 24A positionally regulate each other, and the pinion 16 cannot rotate any further in the counterclockwise direction. Therefore, even if a counterclockwise rotational force is applied to the tuning knob 15, the teeth of the pinion 16 will not jump over the teeth of the meshing tuning gear 14.

When the tuning knob 15 is turned clockwise, the locking groove 23B is reached at the rotation end position in the same manner as described above.
Since the bottom surface of the pin and the locking pin 24B come into contact with each other to regulate the position of each other, it is possible to prevent the pinion 16 from jumping.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, one embodiment in which the gear device according to the present invention is applied to a tuning device will be described in detail with reference to the drawings. The same parts as those described above are designated by the same reference numerals and detailed description thereof is omitted.

FIG. 1 shows the configuration of a tuning device 1 to which the gear device of the present invention is applied.
7 is a plan view in which 7 is partially omitted. FIG. This tuning device 1
In FIG. 1, the variable condenser 12 is mounted on the substrate 11, and the tuning gear 14 is fixed to the rotary shaft 13 of the variable condenser 12. A tuning knob 15 is arranged on the side of the variable capacitor 12 as shown in FIG. 2, and is rotatably attached to the substrate 11.

A pinion 16 is provided below the tuning knob 15 and meshes with the tuning gear 14. A rack 18 is meshed with the pinion 16. A tuning pointer 20 is attached to the rack 18 at an appropriate position, and this is displayed on a display unit 19 provided in the cabinet 17, for example, a display 19A indicating a reception frequency.
Is designed to point to. Now, tuning knob 15
When is turned, the variable condenser 12 is rotated via the pinion 16 and the tuning gear 14, and an arbitrary frequency can be selected and received. Further, at this time, the rack 18 moves, and the tuning pointer 20 comes to point to the display 19A corresponding to the reception frequency of the variable condenser 12.

Now, in this tuning apparatus 1, as shown in FIG.
As shown in, the stopper 2 located above the tuning gear 14 between the tuning knob 15 and the pinion 16.
1 is provided. As shown in FIG. 1, the stopper 21 is provided with two locking pieces 22A and 22B at appropriate intervals, and its outer surface has a semicircular engagement at an appropriate distance from the center of the tuning knob 15. Stop groove 23A, 23B
Is provided.

On the other hand, on the upper surface of the tuning gear 14,
Two locking pins 24A and 24B are provided so as to project at appropriate intervals. These locking pins 24A and 24B are provided with stoppers 2 when the tuning knob 15 is turned as described later.
The first engaging grooves 23A and 23B are in contact with each other.

When the tuning knob 15 is rotated counterclockwise in order to select the program having the lower frequency, the locking grooves 23A, 2A of the stopper 21 are rotated as shown in FIG.
3B also rotates counterclockwise. At this time, since the tuning gear 14 rotates clockwise, the locking pins 24A, 2
4B also rotates clockwise. Then, when the tuning pointer 20 points to the display 19A of 530 kHz in the case of the lowest frequency, AM, the bottom surface of the locking groove 23A comes into contact with the locking pin 24A. In this example, in the vicinity of the line connecting the center of the tuning knob 15 and the center of the tuning gear 14,
The locking pin 24 and the bottom surface of the locking groove 23A come into contact with each other.

When the tuning knob 15 is further turned counterclockwise from this state, a force for rotating the locking groove 23A in a counterclockwise direction acts, and a force for rotating the locking pin 24A in a clockwise direction is applied. To work. However, the locking groove 23
A and the locking pin 24A are in contact with each other, that is, intersect with each other at only one point. After the contact, even if a counterclockwise rotational force is applied to the locking groove 23A, the locking groove 23A and the locking pin 24
And and regulate each other's position, and both cannot rotate. That is, the tuning knob 15 and the pinion 1
6, the tuning gear 14 and the variable condenser 12 are locked. Therefore, in this state, the teeth of the pinion 16 do not jump over the teeth of the tuning gear 14 and the pinion 16 does not rotate, so that the rack 18 moves and the tuning pointer 20 has a frequency different from the reception frequency of the variable condenser 12. There is no need to point to the display 19A.

Similarly, when the tuning knob 15 is rotated in the clockwise direction to select the program with the higher frequency,
As shown in FIG. 4, the locking grooves 23A and 23B and the locking pin 24
A and 24B rotate clockwise and counterclockwise, respectively. And the reception frequency of the variable condenser 12 is the highest frequency,
In this example, at 1600 kHz, the bottom surface of the locking groove 23B and the locking pin 24B abut on the line connecting the center of the tuning knob 15 and the center of the tuning gear 14. With this, the locking groove 23B and the locking pin 24B are the same as described above.
Are mutually restricted in position, and even if a clockwise rotational force acts on the locking groove 23B, they cannot rotate any more. Therefore, the teeth of the pinion 16 do not jump over the teeth of the tuning gear 14 and the pinion 16 does not rotate, and the reception frequency of the variable condenser 12 and the frequency display 19A indicated by the tuning pointer 20 do not differ.

The locking groove 2 is formed so that the urging force acts at an angle close to a right angle with respect to the movement loci of the locking pins 24A and 24B.
If the shapes of 3A and 23B are set, the mutual position regulating force becomes large, and it becomes possible to reliably lock each part. When the pinion 16 rotates once or more,
As shown in FIG. 5, the locking groove 23 is formed during the rotation of the variable capacitor 12.
The locking pins 24A and 24B may be arranged at positions retracted from the locking grooves 23A and 23B when the A and 23B pass over the tuning gear 14. In addition,
INDUSTRIAL APPLICABILITY The present invention can be applied not only to the tuning device 1 described above, but also to various devices such as a volume that require gear tooth jump prevention.

[0021]

As described above, according to the present invention, in a gear device in which a pair of gears that mesh with each other are stopped at a predetermined rotation position, locking means for locking the pair of gears at a predetermined rotation position. Is provided.

Therefore, according to the present invention, at the rotation end position of the pair of gears in mesh with each other, the rotation of the gear is not stopped by the teeth of each other, but the rotation of the gear is stopped by the locking portion provided on the gear. As a result, it is possible to reliably prevent tooth skipping.

[Brief description of drawings]

FIG. 1 is a plan view showing a configuration of a tuning device 1 to which a gear device according to the present invention is applied.

FIG. 2 is a view taken in the direction of arrows BB in FIG.

FIG. 3 is a plan view showing a stopped state at the lowest frequency.

FIG. 4 is a plan view showing a stopped state at the highest frequency.

FIG. 5 is a plan view showing a configuration of a modified example.

FIG. 6 is a cross-sectional view showing a tuning device 1 of a conventional example.

FIG. 7 is a view on arrow AA of FIG. 6;

[Explanation of symbols]

 1 Tuning Device 12 Varicon 14 Tuning Gear 16 Pinion 18 Rack 19 Display 21 Stopper 22A, 22B Locking Piece 23A, 23B Locking Groove 24A, 24B Locking Pin

Claims (2)

[Claims] 1. A gear device in which a pair of meshing gears are stopped at a predetermined rotation position, wherein a locking means for locking the pair of gears at the predetermined rotation position is provided. Gear device. 2. The gear device according to claim 1, wherein the locking means is a locking pin provided on one of the pair of gears and a locking groove provided on the other.