JPS5822248Y2 - 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 consists of 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 crimped to the vertical part 2. , it is now fixed by screws, adhesives, etc., and the button A- shown in Figure 1.
The shapes seen in the cross section along the A line can be roughly classified as shown in Figure 2 A.
,B.

It has a shape as shown in C.

Furthermore, in terms of materials and molding means, it is made by forging, die-casting, and molding from light alloys such as aluminum, magnesium, and ceramics, or by molding plastic.

-t, characteristics required of this type of head shell include being light and flexible, being resistant to bending and torsion, and having a high vibration damping rate.

However, although the conventional Herad shell is lightweight, it lacks bending and torsional strength, which causes partial resonance to occur 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 have been made by cutting carbon fiber into short pieces and molding it into plastic, or by using long fibers. Even the ones that had a flat shape as shown in Figure 2C,
It was difficult to mold the cross-sectional shape as shown in FIGS. 2A and 2B.

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 helad shell.

In addition, in the latter case, since a hole is required for attaching the connector to the vertical part 2 shown in Figure 1, the mechanical strength (bending rigidity, torsional rigidity) between the head shell and the connector cannot be increased, and the sufficient effect cannot be achieved. Not 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 eliminates the above-mentioned conventional drawbacks, and provides 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. With the goal.

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

A cylindrical body 6 is obtained by forming a fibrous layer 5 of carbon fiber on the outer periphery of a cylindrical base material 4 made of a light alloy such as aluminum, titanium, magnesium, or other lightweight press-formable material.

This interlocking fiber layer 5 may be a single layer, but it may also be laminated so that the fiber directions are different. FIG. A second layer 5b formed by spirally winding a prepreg sheet is shown.

In this way, the straightness of the fibers can be effectively utilized, and the bending, twisting, and strength can be further increased.

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

The cylindrical body 6 obtained as described above is impregnated with an epoxy resin or other thermosetting resin by vacuum impregnation method or other means, and a part of the cylindrical body is formed by heating and pressure molding as shown in FIG. It is crushed to form a flat part 7 for attaching the cartridge.

In this case, the reinforcing core materials 8, 8 are inserted so as to be positioned on both sides of the flat part γ in a pressed state, and by further pressing, the reinforcing core materials 8, 8 are integrally placed on both sides of the flat part T. Built-in fixation.

This reinforcing core material 8 is desirably made of a material with a larger elastic modulus than the base material 4, but may be rod-shaped or pipe-shaped.

The shell main body 10 is constituted by the flat part 1 in which the reinforcing core material is built and the remaining cylindrical part 9, but since the cartridge (not shown) is attached to the lower surface of the flat part I, the shell body 10 is flat. It is preferable that the housing be formed so as to be biased toward the outer circumferential direction with respect to the axis 6a of the cylindrical body 6.

In the figure, reference numeral 11 indicates a cartridge mounting hole drilled in the flat portion 7, and reference numeral 12 indicates a terminal insertion hole drilled in the wall portion 11 formed by pressing.

The connector 3 is attached to the opening of the remaining cylindrical portion 9 using screws 13 or the like.

As mentioned above, carbon fiber was used in the examples, but it is not necessarily limited to carbon fiber, and can be used for F'RP (fiber reinforced plastics) such as boron fiber and glass fiber, and has low specific gravity and high elasticity. It is fine as long as you have it.

Further, by forming the cylindrical body 6 into a long length and cutting it into a predetermined length, a uniform number of helad shells can be obtained, and the flat part 7 has an offset angle with respect to the axis 6a. You can also make it possible to do so.

In addition, in a laminated type as shown in FIG. 5, the fiber layer 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,
It has a fiber layer made of fibers with low specific gravity and high elasticity such as carbon fiber around the outer periphery of the base material such as light alloy, so it is lightweight and has excellent mechanical strength.Moreover, it has a flat surface for mounting the cartridge. The part is formed by crushing a part of the cylindrical body, and the flat part is integrally molded from the remaining cylindrical part, so it can be viewed as an extension of the pipe, so it is not open. The opening ability and torsional rigidity can be increased, and in particular, the flat part is reinforced by the reinforcing core material built into both sides of the flat part, making the above rigidity even stronger, thereby preventing the occurrence of partial resonance. It is possible to improve the sound quality.

In addition, by incorporating the reinforcing core material, there is no significant increase in mass and the uniform mass is small, so the record is not affected by warping or eccentricity, and the occurrence of cross-modulation distortion can be suppressed. By incorporating the reinforcing core material, different materials are combined, which disperses resonance and has the advantage of reducing so-called shell noise.

Since the button and connector are configured to be attached to the opening of the remaining cylindrical portion, there is no need for large holes for attachment, mechanical strength can be maintained greater, and assembly is easy.

[Brief explanation of the drawing]

1 and 2 show a conventional head shell for a pickup arm, with FIG. 1 being a sectional view and FIG. 2 being a sectional view taken along the line A--A in FIG. 1. FIG. 3 is a frequency characteristic diagram of a conventional head shell. 4 to 1 show an embodiment of the present invention, FIG. 4 is a sectional view of the cylindrical body, FIG. 5 is a perspective view of the same as above, FIG. 6 is a front view of the shell body, and FIG. 7 is a connector. FIG. 2 is a sectional view showing a state in which the 3... Connector 4... Paste material, 5... Tilt fiber layer, 6... Cylindrical body, 6a... Axis of cylindrical body, I...
Flat part, 8... Reinforcement core material, 9... Remaining cylindrical part, 10
...Shell body.

Claims (1)

[Claims for Utility Model Registration] 1. A base material made of a light alloy or other material that can be press-formed, and around the base material, carbon fiber or other fibers with low specific gravity and high elasticity are solidified with thermosetting resin and molded. A flat part for attaching the cartridge is formed by crushing a part of the cylindrical body made of the fiber layer, and a reinforcing core material is built into both sides of the flat part, and the connector is inserted into the remaining cylindrical part. A head shell for a pickup arm, characterized in that it is configured to be attached to an opening. 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. 3. The head shell for a pickup arm according to claim 1, wherein the fiber layer is made of the same or different fibers and is laminated with the fiber directions being the same or different.