JPH018017Y2 - - Google Patents

Description

[Detailed description of the invention] (a) Industrial application field The present invention relates to a tuning device used in a radio receiver.

(b) Prior art Recently, audio equipment called a tape recorder with radio, which combines a radio receiver and a tape recorder, has become popular. As the shape becomes larger, the dial display board that displays the received frequency is also becoming longer. When such a dial display board becomes longer, the distance of the pointer indicating the received frequency becomes longer, and the number of rotations of the tuning knob for tuning operation increases. One possible way to improve this problem is to lengthen the distance that the dial thread travels by rotating the tuning knob, but such a method has the disadvantage that accurate tuning cannot be easily achieved. There is. There is a device that solves this problem, as disclosed in Japanese Utility Model Application Publication No. 55-24899, which is equipped with a coarse adjustment knob that allows the pointer to travel a large distance and a fine adjustment knob that allows the pointer to travel very slightly.

(c) Purpose of the invention The present invention is intended to provide a tuning device with a novel configuration, which is equipped with a coarse adjustment knob that allows the pointer to travel a large distance and a fine adjustment knob that allows the pointer to travel extremely slightly.

(d) Structure of the invention The invention consists of a drive shaft around which a dial thread is wound, on which a pointer indicating the tuning frequency is attached, and a part of the periphery of the drive shaft that is fixed to the drive shaft and serves as an operating part. a coarse adjustment knob that projects outside the cabinet and is integrally formed with a first gear; and a first rotating shaft that is rotatably and axially displaceably attached to the cabinet and to which the fine adjustment knob is fixed. a first bevel gear formed at the end of the first rotating shaft; a second rotating shaft formed with a second bevel gear in mesh with the bevel gear; and a second rotating shaft fixed to the other end of the second rotating shaft and moving to an operating position in the axial direction of the second rotating shaft. The second gear meshes with the first gear formed on the coarse adjustment knob when the knob is displaced, and a spring returns the second rotating shaft to the non-operating position.

(E) Embodiment FIG. 1 is a front view of a radio receiver incorporating the tuning device of the present invention, and FIG. 2 is a side sectional view of the main parts. In the figure, 1 is a cabinet constituting a radio receiver, and 2 is a dial display board provided on the front surface of the radio receiver. Reference numeral 3 designates a drive shaft around which a dial thread 4 to which a pointer (not shown) is attached is wound, and which moves the pointer by its rotation, and is rotatably mounted on a mounting board 5 provided inside the cabinet 1. It is being Reference numeral 6 denotes a rough adjustment knob fixed to the drive shaft 3 to directly rotate the drive shaft 3, and a part of the peripheral edge thereof is projected to the outside through a hole 1a formed in the cabinet 1 as an operating portion 6a. At the same time, the first gear 7 is integrally formed. Reference numeral 8 designates a first rotating shaft that is rotatably and displaceably mounted on the cabinet 1, and reference numeral 9 designates a fine adjustment knob that is fixed to an externally protruding portion 8a of the first rotating shaft 8. It is arranged below the knob 6. 10 is a first bevel gear formed at the end of the first rotating shaft 8; 11 is a spring that biases the first rotating shaft 8 in the direction of arrow A; 12 is a first bevel gear formed on the first rotating shaft 8; This is a stopper portion that restricts displacement of the first rotating shaft 8 in the direction of arrow A. Reference numeral 13 denotes a second rotating shaft that is rotatably and axially displaceably attached to a mounting board 14 provided inside the cabinet 1; 15 is the second rotating shaft 13;
is formed at the end of the first rotating shaft 8.
A second bevel gear 16, which is always in mesh with the first bevel gear 10 formed in the second bevel gear 10, is fixed to the end of the second rotating shaft 13, and the second rotating shaft 13 is in the operating position. When the coarse adjustment knob 6 is displaced in the direction of arrow B, the first
A second gear 17 that meshes with the gear 7 is a spring that biases the second rotating shaft 13 in the direction of arrow C.
It goes without saying that the variable capacitor and the like can be varied by rotating the drive shaft 3.

The tuning device of the present invention is constructed as described above, and its operation will be explained next. When the fine adjustment knob 9 is not operated, the first gear 7 formed on the coarse adjustment knob 6 and the second gear 16 fixed to the second rotating shaft 13 are in a non-meshing state, as shown in FIG. It is in. When in such a state, coarse adjustment knob 6
When the externally protruding portion, that is, the operating portion 6a is operated, the coarse adjustment knob 6 rotates, causing the drive shaft 3 to rotate.
When the drive shaft 3 rotates, the dial thread 4 wound around the drive shaft 3 is moved. During such operation, the drive shaft 3 is directly rotated, so the pointer attached to the dial thread 4 moves. It will be forced to move significantly. Although the channel selection operation using the coarse adjustment knob 6 is performed in this manner, the channel selection operation using the fine adjustment knob 9 will be explained next. Tuning operation using the fine adjustment knob 9 is performed by rotating the fine adjustment knob 9 while pressing it in the direction of arrow D. When the fine adjustment knob 9 is pressed in the direction of arrow D, the first rotating shaft 8 is pushed and displaced in the direction of arrow D against the biasing force of the spring 11. When the first rotating shaft 8 is displaced in the direction of arrow D, the second bevel gear 15 receives a pressing displacement force in the direction of arrow B due to the contact force of the first bevel gear 10 against the second bevel gear 15. As a result, the second bevel gear 15
The second rotating shaft 13 on which the spring 1 is formed
The second gear 16, which is fixed to the second rotating shaft 13, is moved to the operating position in the direction of arrow B against the biasing force of mesh together. Therefore, in such a state, that is, when the fine adjustment knob 9 is rotated while being pressed in the direction of arrow D, the rotation of the knob 9 is as follows: first bevel gear 10 - second bevel gear 15 - second gear 1
6- It is transmitted to the drive shaft 3 via the first gear 7 and moves the dial thread 4. In this way, the rotation of the fine adjustment knob 9 is transmitted to the drive shaft 3, so if the transmission ratio between the first gear 7 and the second gear 16 is appropriately selected, the rotation of the drive shaft 3 relative to the rotation of the fine adjustment knob 9 can be controlled. It can be reduced. Therefore, when a tuning operation is performed using the fine adjustment knob 9, the amount of movement of the pointer attached to the dial thread 4 is small, so that the tuning operation can be performed accurately. The tuning operation using the fine adjustment knob 9 is performed as described above, but when the fine adjustment knob 9 is released after the tuning operation, the first rotation shaft 8 and the second rotation shaft 13 are rotated due to the force of the springs 11 and 17, respectively. It is returned to the non-operating position shown in FIG.

In this embodiment, two springs are provided: a spring 11 for returning the first rotating shaft 8 to the non-operating position and a spring 17 for returning the second rotating shaft 13 to the non-operating position. Since the force can be obtained from the spring 17, the spring 11 is not necessarily required.

(f) Effects of the invention The tuning device of the invention has a coarse adjustment knob that allows the pointer to travel a large distance and a fine adjustment knob that allows the pointer to travel slightly.As the dial display board becomes longer, the distance that the pointer travels becomes longer. It is possible to quickly and accurately perform a channel selection operation. In addition, a part of the coarse adjustment knob protrudes outside as an operating part,
Since the fine adjustment knob is placed externally, the present invention has the advantage that it is possible to easily recognize which knob is coarse adjustment or not. During tuning operation using the coarse adjustment knob, the first gear and the second gear are in a non-meshing state, so the transmission mechanism for fine adjustment does not apply any load to the coarse adjustment knob, and the tuning operation force generated by the coarse adjustment knob is not applied. It has the feature that it can be made lighter, and the practical value of the present invention is extremely large.

[Brief explanation of the drawing]

The drawings all relate to the tuning device of the present invention; FIG. 1 is a front view of the radio receiver, and FIG. 2 is a side sectional view of the main parts. Explanation of main drawing numbers, 1...cabinet, 2...
Dial display board, 3... Drive shaft, 4... Dial thread, 6... Coarse adjustment knob, 7... First gear, 8...
1st rotating shaft, 9... fine adjustment knob, 10... first bevel gear, 13... second rotating shaft, 15... second bevel gear, 16... second gear.

Claims (1)

[Scope of utility model registration request] A drive shaft around which a dial thread is wound around which a pointer indicating the tuning frequency is attached; a coarse adjustment knob having a first gear formed thereon; a first rotating shaft that is rotatably and axially displaceably mounted on the cabinet and to which the fine adjustment knob is fixed; and an end portion of the first rotating shaft. The first formed in
A second bevel gear is rotatably and axially displaceably attached to the bevel gear and a mounting board provided inside the cabinet, and a second bevel gear is formed at an end thereof in mesh with the first bevel gear. A second rotating shaft and a first gear fixed to the other end of the second rotating shaft and formed on the coarse adjustment knob by displacement to an operating position in the axial direction of the second rotating shaft. A tuning device comprising a mating second gear and a spring for returning said second rotating shaft to an inoperative position.