JPS5822246Y2 - Head seal for pickup arm - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a head shell for a pickup arm.

Conventionally, as shown in Fig. 1, this type of herad shell has a horizontal part 1 for attaching a cartridge and a vertical part 2 for attaching a connector formed at the rear end, and a connector 3 is attached to the vertical part 2. It is fixed by caulking, screwing, adhesion, or other means, and the cross-sectional shapes of the horizontal portion 1 are broadly classified into shapes as shown in FIGS. 2A, B, and C.

In terms of materials and molding means, they are made of light alloys such as aluminum, magnesium, ceramics, etc., die-casting, molding, or plastic molding.

In general, characteristics required of this type of head shell include being lightweight, strong against bending and torsion, and having a high vibration damping rate.

However, although the conventional Herad shell is lightweight, it lacks bending and torsion strength, and as a result, it is difficult to generate partial resonance as shown by r in the frequency characteristic diagram in Figure 3. As a result, the sound quality deteriorates.

This is caused by the lack of strength of the head shell when viewed from connector 3.

Head shells using carbon fiber have been proposed to improve the above-mentioned drawbacks, but these are ones that are molded by mixing short pieces of carbon fiber into glass plastic, or those that use long fibers. Even with the existing ones, it was difficult to mold them into a cross-sectional shape as shown in FIG. 2 At B, and they were only in the shape of a flat plate as shown in FIG. 2 C.

Therefore, in the former case, cutting the carbon fiber into short pieces significantly reduces the mechanical strength, especially the flexural modulus, and although it serves as reinforcement for the plastic, it is not satisfactory as a head shell.

In the case of the latter case, since it is molded into a flat plate shape as shown in Figure 2C, it does not have sufficient torsional rigidity, and furthermore, a hole for attaching the connector is required in the vertical part 2, so the mechanical connection between the head shell and the connector is The strength cannot be increased and sufficient effects cannot be obtained.

As described above, conventional herad shells using carbon fibers have the disadvantage that the excellent properties of carbon fibers, such as light weight and high flexural modulus, are not fully exhibited.

The present invention aims to eliminate the above-mentioned conventional drawbacks, to provide a head shell that satisfies the characteristics required of a head shell, prevents the occurrence of partial resonance in frequency characteristics, and thereby improves sound quality. purpose.

Embodiments of the present invention will be described below based on the drawings from FIG. 4 onwards.

A cylindrical body 4 is formed by winding carbon fiber around a brypreg sheet tiger winding shaft.

In this case, in the case shown in FIG. 4, the fibers are laminated in different directions, including a first layer 5 oriented in the axial direction, a second layer 6 spirally wound around the outer periphery of the first layer 5, and a second layer 6 spirally wound around the outer periphery of the first layer 5. The third layer I is spirally wound in the opposite direction to the second layer 6, and the fourth layer 8 is formed linearly around the outer periphery of the third layer I in the same manner as the first layer. .

By laminating prepreg sheets as shown in FIG. 4, the linearity of the fibers can be effectively utilized, and the bending and torsional strength can be further increased.

The one shown in FIG. 5 is made by knitting carbon fibers into a pipe shape, and since the straightness of the fibers is somewhat sacrificed, it is less strong than the one shown in FIG. 4.

The above-mentioned cylindrical body does not have to be cylindrical, and may be a rectangular cylinder, but from the viewpoint of molding and the shape of the connector, a cylindrical shape is preferable.

The cylindrical body 4 obtained as described above is impregnated with epoxy resin or other thermosetting resin by vacuum impregnation method, and a part of the cylindrical body is crushed by heating and pressure molding to attach the cartridge. A flat part 9 for use is formed.

In that case, as shown by the imaginary lines in FIG.
0 and 10 and press further to form a flat part 9.
Reinforcing core materials 10, 10 are integrally fixed and built into both side edges of the 0 side.

The reinforcing core material 10 is preferably made of a material having a larger elastic modulus than the material of the cylindrical body 4, and may be a rod-shaped body or a pipe.

Incidentally, since the cartridge/fuji is attached to the lower surface of the flat part 9, it is desirable that the flat part be formed offset toward the outer circumference from the axis 4a of the cylindrical body.

A shell main body 12 is constituted by the flat portion 9 and the remaining cylindrical portion 11 thus formed.

13 is a cartridge mounting tag drilled in the flat portion 9;
Reference numeral 15 denotes a terminal insertion hole bored in the wall portion 14 formed by the above-mentioned press.

The connector 3 is inserted into the opening of the remaining cylindrical portion 11 with a screw 16.
etc. is fixed.

Although carbon fiber was used for the button in the above embodiment, it is not necessarily limited to this, and any material that can be used such as boron fiber or glass fiber Machi RP (fiber reinforced plastic) and has low specific gravity and high elasticity may be used. Bye.

Further, by forming the cylindrical body 4 into a long length and cutting it into a predetermined length with a button, a large number of uniform helad shells can be obtained, and the flat part 9 has an offset angle with respect to the axis 4a. You can also do it like this.

3. In the case of the laminated cylindrical body shown in FIG. 4, each sleeve may be formed of different fibers to take advantage of the characteristics of each fiber.

According to the head shell for a pickup arm of the present invention,
The head shell body is molded from fibers with low specific gravity and high elasticity, and it is not only lightweight and has excellent mechanical strength, but also the flat part that serves as the cartridge attachment part is made by pressing a part of the cylindrical body. Therefore, the flat part is integrally molded from the remaining cylindrical part, so it can be thought of as an extension of the pipe, and the bending stiffness and torsional stiffness seen from the connector are extremely low, causing partial resonance. can be prevented.

Moreover, reinforcing core materials are built into both edges of the flat part, making it possible to further increase the mechanical strength of the flat part.By incorporating the reinforcing core materials, there is no significant increase in mass and the image quality is constant. Since only a small amount is required, the record is not affected by warping or eccentricity, and the occurrence of cross-modulation distortion can be suppressed.

Rather, the presence of the reinforcing core material allows dissimilar materials to be combined, which disperses resonance and has the advantage of suppressing so-called shell noise.

Furthermore, since the connector is configured to be attached to the opening of the remaining cylindrical portion, it does not require a large hole for attachment, can maintain greater mechanical strength, and is easy to assemble.

[Brief explanation of the drawing]

Fig. 1 and Fig. 2 show a conventional head shell for a pickup arm, Fig. 1 is a cross-sectional view, Fig. 2 is a cross-sectional view taken along line A-A in Fig. 1, and Fig. 3 is a conventional head shell. FIG. 4 to 8 show an embodiment of the present invention, FIGS. 4 and 5 are perspective views of the cylindrical body, FIG. 6 is a sectional view of the same, and FIG. 7 is a front view of the herad shell body. FIG. 8 is a sectional view showing a state in which the connector is attached. 3... Connector, 4... Cylindrical body, 4a... Axis line, 9... Flat part, 10... Reinforcement core material, 11... Remaining cylindrical part, 12... Head shell Body.

Claims (1)

[Claims for Utility Model Registration] 1. The main body of Heradshell is a cartridge made by crushing a part of a cylindrical body made by solidifying fibers with low specific gravity and high elasticity such as carbon fiber with thermosetting resin. A flat part for attachment and a remaining cylindrical part are formed, a reinforcing core material is built into both edges of the flat part, and the connector is configured to be attached to the opening of the remaining cylindrical part. A head shell for pickup arms that is characterized by: 2. The head shell for a pickup arm according to claim 1, wherein the flat portion is offset toward the outer circumference from the axis of the cylindrical body.