JPS5819690Y2 - Head shell for record pickup - Google Patents

Description

[Detailed description of the invention] This invention relates to damping of harmful resonance in the head shell of a record pink amplifier.

The tone arm and head shell of the Record Pink amplifier reliably support the cartridge, allowing it to move smoothly along the sound groove of the record, and the cartridge can be discarded and converted into an amplifier without damaging the converted electrical signal. It is also necessary to have the ability to reproduce and deliver information.

Therefore, it is desirable for the head shell to be made of a material that is light, has high rigidity, and has a large internal loss.

However, conventional general head shells are made by bending and forming sheet materials, cutting or casting aluminum or magnesium alloy strips, or forming them into special structures in the case of hard synthetic resin. etc. to increase bending rigidity.

However, in the whole record pink amplifier, this head shell part has a lower rigidity than the other parts, so it is commonly called "shell squeal 1" when playing records.

A split resonance of approximately 200 to IKHz occurs due to the stiffness of this head shell, and the resonance sharpness Q of this resonance is due to the fact that the entire record pinkup is mainly composed of metal, etc. with a small amount of internal loss.・Because of this, it became a large value. ・It became a problem in terms of performance.

In other words, the electrical signal output of the Record Pink amplifier is generated by the relative speed between the cartridge vibration system and the cartridge body, and even if the cartridge vibration system faithfully traces the sound groove of the record, the cartridge body may vibrate due to resonance phenomena. For example, this effect also affects the electrical signal output, causing peak dip in the output frequency characteristics.

As mentioned above, conventional record pink amplifiers have insufficient strength, especially in the head shell, and low internal loss, which causes a large Q peak dip in the output frequency characteristics, which has an unfavorable effect on performance. There were drawbacks.

This invention was devised in view of the above-mentioned drawbacks, and the object is to obtain a head shell for a record player that is lightweight, maintains rigidity, and effectively damps resonance.

FIG. 1 is a top sectional view of a head shell for a record player showing an embodiment of this invention, and FIG. 2 is a sectional view taken along line 1--2 in FIG.

In Figures 1 and 2, 1 is skin A made of glass fiber reinforced plastic (GFRP), and 2 is skin A made of glass fiber reinforced plastic (GFRP).
skin B, 3 is a honeycomb-shaped core made of aluminum foil with a thickness of 20 cm, 4 is a viscoelastic material filled in the hollow part of the honeycomb-shaped core 3, and 5 is an electric signal from the cartridge printed on skin B3, which is used to connect the tone arm to the skin B. 6 is a lead wire that guides the electrical signal from the cartridge to terminal 5, 7 is a screw hole for fixing the cartridge, and 8 is a connecting part (not shown) provided on the tone arm. ), the head shell 9 is constituted by the screws that connect and fix the hesodo shell to the head shell 9.

As mentioned above, the skin AI uses the honeycomb-shaped core 3 as the core material,
If the skin B2 is attached to both sides of the honeycomb-shaped core 3 to form a sandwich structure, the rigidity against bending vibration increases or decreases in proportion to the cube of the thickness h.
In's sand inch structure has a bending rigidity 8 times that of a simple aluminum plate with a thickness of 1.5 mm used for conventional head shells, and is less likely to cause split vibration. If the portion is filled with a viscoelastic material, it becomes possible to significantly reduce Q during resonance.

As explained above, this idea is made by filling the hollow part of the nicum-shaped core with a viscoelastic material and gluing skins on both sides to create a sand inch structure, which is lightweight and prevents split vibration of the head shell. Q during resonance can also be made small, which has the advantage of suppressing disturbances in response due to resonance that appear on the output frequency characteristics.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing an embodiment of this invention, with a part of the upper surface cut away, and FIG. 2 is a cross-sectional view taken along the line 1--2. In the figure, 1 is a skin A, 2 is a skin B, 3 is a honeycomb core, and 4 is a viscoelastic body. Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

[Scope of utility model registration request] Made of a thin film of metal or polymeric material, the core material is a nicum-shaped core, the hollow part of the core material is filled with a viscoelastic material, and thin films of metal or reinforced plastic are pasted on both sides. Head shell for Record Pink amplifier with layered sand inch structure.