JPH0434573Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a dial drive device for electronic equipment such as radio receivers and tape recorders.

BACKGROUND ART In recent years, various methods have been considered to configure dial drive devices in smaller and thinner devices in a space-saving and low-cost manner.

Hereinafter, a conventional dial driving device will be described with reference to the drawings.

As shown in FIG. 7, a variable capacitor 4 and other electrical components 5 are mounted on a printed circuit board 3, and a dial chassis 1 is mounted on the printed circuit board 3. A dial rope 7 having a pointer 6 is stretched between a rotary roller 8, a tuning shaft 9, and a dial drum 2 provided on the variable capacitor 4.

Problems to be Solved by the Invention However, the structure of the dial drive device described above has the disadvantage that it requires a large number of parts such as rollers, and requires considerable skill in assembly work, resulting in a large number of man-hours. Ta. In addition, it occupies a large space, which is not desirable for miniaturization. Furthermore, even after it was completed as a dial drive device, the safety factor, operating force, etc. were unstable, and there were major problems in the quality of the set.

The present invention solves these conventional problems and provides a dial drive device that can reduce the number of parts and the number of assembly steps.

Means for Solving the Problems In order to solve the above problems, the dial drive device of the present invention includes a first gear that is rotatably attached to a shaft fixed to the chassis and meshes with a variable condenser gear, and a first gear that is fixed to an adjustment member. a second gear rotatably attached to a shaft fixed to the adjustment member so as to mesh with a gear formed integrally with a tuning knob inserted into the tuning shaft and rotatably attached; The second gear is provided with a timing belt that connects the second gear and the first gear, and is fixed to the adjustment member using the tuning shaft as a support shaft and using the tuning mounting hole of the chassis as a guide.
The gear is capable of rotating while meshing with a gear formed integrally with the tuning knob.

Effect: With the above-described configuration, the present invention can reduce the number of parts and assembly man-hours, and furthermore, it is possible to reduce the space occupied, thereby obtaining a compact dial drive device with stable quality. be able to.

Embodiment Hereinafter, a dial drive device according to an embodiment of the present invention will be described with reference to the drawings. Figure 1~
FIG. 6 shows an embodiment of the present invention. Figures 1 to 6
In the figure, 1 is the cabinet, 2 is the dial chassis, 3 is the tuning knob, 4 is the second gear, 6 is the timing belt, 7 is the first gear, and 8
is a variable capacitor. A variable capacitor 8 with a gear attached thereto and other electrical parts are mounted on a printed circuit board 12, and a dial chassis 2 is mounted on the printed circuit board 12 and fixed with screws 10 and 11. A first gear 7 is rotatably attached to the dial chassis 2 by a shaft 9,
It meshes with the gear attached to variable capacitor 8. A shaft 14 of the second gear 4 is fixed to the adjustment member 15 . Next, the tuning shaft 17 of the tuning knob 3 is fixed to the adjustment member 15 so as to sandwich the dial chassis 2 therebetween. At this time, using the tuning shaft 17 as a support shaft, the adjustment member 15
is rotatably mounted. second gear 4
is inserted into the shaft 14, and the snap washer 1
6 and is rotatably attached. The tuning knob 3 is inserted into the tuning shaft 17 and rotatably attached with a snap washer 16. A gear 18 formed integrally with the tuning knob 3 is attached so as to mesh with the second gear 4. The timing belt 6 meshes with a dedicated gear part integrally formed below the first gear 7 and the second gear 4, transmits the rotation of the tuning knob 3, and rotates the variable capacitor 8. Guideline 9
is press-fitted into the timing belt 6. Next, since the timing belt 6 has dimensional variations between the axes of the first gear 7 and the second gear 4, in order to absorb this variation, a protrusion 19 integrally formed on the adjustment member 15 is provided. The adjustment member 15 is completely fixed to the dial chassis 2 by applying a load in the direction of the arrow and pulling it in the tensioned state by the screws 5. FIG. 2 shows the adjustment member 15 in an unadjusted state. At this time, the second gear 4 maintains a constant meshing with the gear formed integrally with the tuning knob 3, and the pitch between the first gear 7 and the second gear 4 is adjusted, and the timing belt is adjusted to accommodate dimensional variations in the timing belt. The play of the tuning knob is improved.
Reference numeral 13 is a back decoration that is bonded to the printed circuit board 12.

Effects of the invention As described above, according to the invention, in a configuration in which the timing belt is used to transmit the rotation operated by the tuning knob to the variable capacitor, the tuning By providing the second gear so that it can rotate while meshing with the gear formed integrally with the knob, it is possible to reduce the number of parts and man-hours, occupy a small space, and downsize.

[Brief explanation of drawings]

Fig. 1 is a plan view of a dial drive device in an embodiment of the present invention, Fig. 2 is a diagram showing the state before adjustment of Fig. 1, and Fig. 3 is an assembly of the dial drive device in an embodiment of the present invention. A perspective view, FIG. 4 is a sectional view taken along line AA in FIG. 1, and FIG. 5 is a sectional view taken along line BB in FIG. 1.
FIG. 6 is an external view of a radio receiver using a dial driving device according to an embodiment of the present invention, and FIG. 7 is a perspective view of a conventional dial driving device. 1... Cabinet, 2... Chassis, 3...
Tuning knob, 4...Second gear, 5...
Fixing screw, 6... Timing belt, 7...
1st gear, 8... Variable capacitor, 9... Pointer.

Claims (1)

[Scope of utility model registration request] A first gear rotatably attached to a shaft fixed to the chassis and meshing with a variable condenser gear; a tuning knob inserted into and rotatably attached to a tuning shaft fixed to an adjustment member; a second gear rotatably attached to a shaft fixed to the adjustment member so as to mesh with the integrally formed gear; and a second gear rotatably attached to a shaft fixed to the second gear and the chassis. a timing belt that connects the first gear to the tuning knob, and a second gear fixed to the adjustment member using the tuning shaft as a support shaft and using the mounting hole of the chassis as a guide, formed integrally with the tuning knob. A dial drive device configured to be rotated while meshing with a gear.