JPS647478Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a flywheel fixed to a capstan shaft for running a tape in a tape recorder, a video tape recorder, etc., and particularly relates to a structure for preventing thrust vibration of the flywheel.

FIG. 1 shows a conventional example, in which a pusher 3, a pressing spring 4, and a washer 5 are incorporated into a flywheel 2 fixed to a capstan shaft 1 that runs the tape, and in this state, the capstan shaft 1 By supporting the flywheel 2 on the cylindrical member 7 of the chassis 6, the flywheel 2 is always pressed against the thrust receiving plate 8 and rotates. However, in the above-described conventional structure, the washer 5 is loosely fitted to the capstan shaft 1 and can rotate freely, so the presser spring 4 elastically installed between the washer 5 and the flywheel 2 also acts on the rotation of the flywheel 2. As a result, twisting occurs in the same direction, and when this twisting exceeds a certain level, the pressing spring 4 returns to its original state. At this time, a repulsive force in the opposite direction to the rotational direction acts on the flywheel 2, causing rotational unevenness, and this rotational unevenness of the flywheel 2 has the drawback of worsening wow and flutter.

The present invention was made in order to eliminate such drawbacks, and for this purpose, it consists of a flywheel fixed to a capstan shaft, a washer inserted into the capstan shaft and one side of which is positioned in the thrust direction, and a washer that is inserted into the capstan shaft and positioned in the thrust direction. A thrust direction pressing spring of the flywheel is provided between the other surface of the washer and the flywheel, and the flywheel and the washer are engaged with each other in the rotational direction, thereby preventing deterioration of wow and flutter. The purpose is to prevent

Hereinafter, embodiments of the present invention will be described based on FIGS. 2 and 3.

A flywheel 2 is fixed via a spring receiver 9 to the lower end of a capstan shaft 1 through which the tape runs. A cylindrical peak 2a projects from the upper part of the flywheel 2, and a pair of protrusions 2b are formed on the inner wall of the peak 2a. The capstan shaft 1 also has a pair of recesses 5a on its outer circumference.
A washer 5 having a shape formed therein is loosely fitted, and this washer 5 is incorporated inside the mountain portion 2a by fitting the recessed portion 5a into the convex portion 2b. A pressing spring 4 is resiliently provided between the upper surface of the spring receiver 9 and the upper surface of the spring receiver 9 to bias the flywheel 2 in the direction of the opposing thrust receiver plate 8. Further, a hollow cylindrical member 7 is fixed to the chassis 6, and the capstan shaft is rotatably supported by the cylindrical member 7 via a bearing 10, and the lower part of the cylindrical member 7 is Mountain portion 2a of the flywheel 2
The upper surface of the washer 5 is in contact with the bearing 10.

As is clear from the above structure, the pressing spring 4 and the washer 5 rotate integrally with the rotation of the flywheel 2 because the convex portion 2b of the flywheel 2 and the concave portion 5a of the washer 5 are engaged. Therefore, the pressing spring 4 is twisted by the rotation of the flywheel 2, and this twisting force is applied to the flywheel 2.
There is no longer any danger of a repulsive force acting on the lens, and there is no need to worry about worsening wow or flutter.

In the above embodiment, the washer 5 is forcibly rotated with the flywheel 2 by the engagement between the two convex portions 2b formed on the flywheel 2 and the two recessed portions 2a formed on the washer 5. However, the number of the convex portions 2b and concave portions 5a of both is not limited to the above embodiment as long as the engagement of the flywheel 2 and washer 5 in the rotational direction is satisfied. The same effect can be obtained even if the relationship between the concave portion 5a and the concave portion 5a is reversed to that of the above embodiment, that is, the flywheel 2 is formed with a concave portion and the washer 5 is formed with a convex portion.

As described above, the present invention includes a flywheel fixed to a capstan shaft, a washer inserted into the capstan shaft and positioned on one side in the thrust direction, and a flywheel provided between the other surface of the washer and the flywheel. The flywheel is characterized in that the flywheel and the washer are engaged with each other in the rotational direction.

With this configuration, the present invention allows the pressing spring and washer to rotate together with the flywheel, and therefore no torsional force is generated in the pressing spring that prevents thrust vibration of the flywheel. Therefore, uneven rotation of the flywheel is eliminated, and the danger of worsening wow and flutter can be eliminated.

[Brief explanation of the drawing]

Figure 1 is a sectional view of the main parts in the conventional example, Figure 2
The figure is a sectional view of the main parts of the present invention, and FIG. 3 is a perspective view of the main parts of the present invention. 1... Capstan shaft, 2... Flywheel, 2a... Mountain part, 2b... Convex part, 3... Button, 4... Press down, 5... Washer, 5a...
... recessed part, 6 ... sheath, 7 ... cylindrical member, 8
... Thrust bearing plate, 9 ... Spring support, 10 ... Bearing.

Claims (1)

[Scope of utility model registration request] A flywheel fixed to a capstan shaft, a washer inserted into the capstan shaft and positioned on one side in the thrust direction, and a thrust direction pressing spring for the flywheel provided between the other surface of the washer and the flywheel. A structure for preventing thrust vibration of a flywheel, characterized in that the flywheel and the washers are engaged with each other in a rotational direction.