JPS6153778B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a flywheel attached to a capstan shaft or the like in a tape recorder.

Generally, a capstan device used in a tape recorder has a structure as shown in FIG. That is, at one end of the capstan shaft 2,
A flywheel 1 made of zinc, iron, etc. having a high specific gravity is integrally fitted to increase the inertial mass, and a capstan shaft 2 to which the flywheel 1 is attached is bored into a mechanical chassis 3 that constitutes the main body of the tape recorder. It is inserted and fitted into the provided through hole 4 and is attached so as to be inserted through a bearing 6 which is attached to one side surface of the chassis 3 with a flange portion 5 in a position-controlled manner. Bearing metals 7, 7 are interposed between the capstan shaft 2 and the bearing 6, and the capstan shaft 2 is rotatable. Further, one end of the capstan shaft 2 to which the flywheel 1 is attached is supported by a thrust receiver 8, and a pinch roller 9 that is moved and operated by a predetermined operating means is in pressure contact with the tip side opposite to this one end. do.

When the tape is driven, the pinch roller 9 comes into pressure contact with the capstan shaft 2 to pinch the magnetic tape 10, and the capstan shaft 2 is rotationally driven by a drive motor (not shown) to cause the magnetic tape 10 to travel.

During such tape drive, the capstan shaft 2 rotates and slides between the bearing metals 7, 7, and during this rotation and sliding, the rotational friction generated between the bearing metals 7, 7 causes vibrations, etc. A disturbance occurs. Therefore, when driving the tape, the capstan shaft 2
The flywheel 1, which is integrally attached to the capstan shaft 2, is constantly subjected to disturbances such as vibrations. Therefore, the vibration specific to the flywheel 1 is excited by the above-mentioned disturbance. In particular, since the flywheel 1 is made of metal as described above, the resonance sharpness Q is sharp, and even if there is a slight disturbance, the magnetic tape 10
The impact will be greatly expanded. That is, the vibration inherent to the flywheel 1 is transmitted via the capstan shaft 2, and the vibrations inherent to the flywheel 1 are transmitted to the running magnetic tape 10.
This causes the magnetic head to vibrate, disrupting the sliding contact with the magnetic head, and causing deterioration of recording and reproducing characteristics.

Therefore, the present invention proposes a manufacturing method that makes it possible to easily provide a flywheel that can prevent deterioration of the recording and reproducing characteristics of a tape recorder.

Hereinafter, specific embodiments of the present invention will be described with reference to the drawings.

In the present invention, first, a flywheel as shown in FIG. 2 is prepared. This flywheel 1 is made of metal such as zinc or iron like the conventional one, and the center of rotation of the flywheel body 11 has a fitting hole 12 into which one end of the capstan shaft 2 is integrally fitted. It is perforated. Further, on one side of the flywheel main body 11, that is, on the lower surface side opposite to the side to which the pinch roller comes into pressure contact when the capstan is constructed by fitting the capstan shaft 2, a recess 13 is provided concentrically with the main body 11. is formed. A part of the capstan shaft 2 is fitted into the fitting hole 12 of the flywheel 1 formed in this way, so that the flywheel main body 11 and the capstan shaft 2 are integrated as shown in FIG.

Next, in the recess 13 of the flywheel main body 11 into which the capstan shaft 2 is fitted as described above, a single layer or a multilayer filler 14 having a resonance sharpness Q smaller than the resonance sharpness Q of the flywheel main body 11 is applied. They are fixed in layers and integrated with the flywheel main body 11 as shown in FIG. In addition, filler 1
4 may be fixed to the recess 13 partially or with non-uniform thickness.

Here, as the filler 14, a tex having the composition shown below is used.

Resin: 8% by weight (or 19% by weight) Cobalt naphthenate added as oil-modified alkyd resin catalyst Filler: 73% by weight Calcium carbonate granules 85% by weight Glass powder 10% by weight Asbestos 5% by weight Solvent: 19% by weight % (or 8% by weight) Petroleum benzene 32% by weight Toluene 57% by weight Xylene 11% by weight Filler 1
When used as No. 4, it is fixed and integrated by the following method. That is, the above-mentioned text is applied or poured into the recess 13 of the flywheel body 11 to a desired thickness, and then dried to be fixed and integrated.

Alternatively, oil clay or pitch can be used as the filler 14. When such oil clay or pitch is used, it is applied or poured into the recess 13 of the flywheel body 11 to a desired thickness, and then dried to solidify and integrate, as in the case of text.

Furthermore, a rubber sheet having a predetermined thickness may be used as the filler 14. When such a rubber sheet is used, the recess 1 of the flywheel body 11
Step 3: Use adhesive to attach and secure to integrate. Similarly, the resonance sharpness Q of the flywheel body 11
Felt or the like having a resonance sharpness Q smaller than the above may be used as the filler 14.

By the way, as mentioned above, the flywheel body 1
When forming the recess 13 in the flywheel main body 11, the filler 14 integrated into the flywheel main body 11 is arranged so that it does not go over the arc-shaped rising peripheral wall 15 formed near the outer peripheral edge of one side of the flywheel main body 11. It is desirable to fill the recess 13 with the adhesive and fix it there.

After the filler 14 is fixed and integrated with the flywheel main body 11 as described above, the flywheel main body 11 is subjected to a mass correction process using a balance machine. For example, flywheel body 1
As shown in FIG. 5, a conical notch 16 is bored by a balance machine on the other side opposite to the one side on which the recess 13 is formed, and a mass correction process is performed. Alternatively, a resin for mass correction may be attached to a part of the flywheel body 11. This mass correction is for correcting the rotational balance of the flywheel 1 caused by fixation of the filler 14 or the like.

A flywheel obtained by fixing and integrating a filler having a resonance sharpness Q smaller than the resonance sharpness Q of the flywheel body 11 on one side of the flywheel body 11 by the method described above is a flywheel. The overall resonance sharpness Q can be reduced. As a result, it is possible to reduce the resonance sharpness caused by vibrations specific to the flywheel caused by disturbances such as vibrations generated by rotational friction between the capstan shaft and the bearing metal during tape drive.

Therefore, the influence of vibration on the running magnetic tape can be eliminated, and deterioration of recording and reproducing characteristics can be prevented.

Furthermore, according to the method of the present invention, mass correction is performed after the filler is fixed and integrated, so that operations such as applying the filler become easier. This is especially advantageous since it is extremely difficult to uniformly apply and cure fillers. Furthermore, since the mass correction is performed in the final step, it can be performed in one operation, thereby improving work efficiency.

In the above-described embodiment, the flywheel for a capstan was explained, but the present invention is not limited to this and can be widely applied to the manufacture of flywheels for tape recorders.

[Brief explanation of the drawing]

FIG. 1 is a schematic sectional view showing a capstan device in a conventional tape recorder. FIG. 2 is a perspective view showing the flywheel body used in the present invention, FIG. 3 is a sectional view showing the flywheel body and the capstan shaft integrated, and FIG. 4 is a perspective view of the flywheel body used in the present invention. FIG. 3 is a sectional view showing a state in which a filler is fixed and integrated in a recess. FIG. 5 is a sectional view showing a flywheel whose mass has been corrected by a balance machine. 2...Capstan shaft, 1...Flywheel, 11...Flywheel body, 13...Recess in flywheel body, 14...Filling material.

Claims (1)

[Claims] 1 A filler having a resonance sharpness Q smaller than the resonance sharpness Q of the flywheel body is fixed to a recess formed on one side of the flywheel body made of metal such as zinc or iron. A method for manufacturing a flywheel for a tape recorder, characterized in that the flywheel is integrated with a flywheel body, and then the flywheel body is subjected to mass correction processing using a balance machine.