JPS6033675Y2 - Pickup Cartridge - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a pickup cartridge, and particularly to a pickup cartridge with improved low frequency characteristics.

In general, a pickup cartridge resonates due to the compliance of the stylus tip and the equivalent mass of the tone arm including the pickup cartridge's own weight, causing resonance in the low frequency range of several Hz to several tens of Hz, creating a large resonance peak.
When a record is warped or a reduction noise is introduced into the signal, it shakes and causes cross-modulation, needle skipping, etc.

For this reason, it has been proposed to brake the rotation shaft of the tone arm with oil, but this reduces sensitivity and causes a change in stylus pressure on warped records.

For this reason, a device has been proposed that uses a weight at the rear of the tone arm to cause anti-resonance and perform braking, but this configuration has a mass limit and cannot provide good characteristics.

That is, in this configuration, as shown in Fig. 1, resonance is caused by the compliance component C2, the mass M1 on the cartridge side, and the mass M2 on the counterweight side, and harmful vibrations are damped by anti-resonance against vibrations from the record side. do.

However, the tone arm resonates with vibrations from the arm base side, especially since both the mass M□ on the cartridge side of the tone arm and the mass M2 on the counterweight side are large, causing the tone arm to wobble.

Therefore, a means to prevent vibration from the arm base is required.

In addition, the compliance to configure anti-resonance must be set in accordance with the compliance of the tip of the pickup cartridge, and with universal arms, etc., it is necessary to match this compliance to the cartridge being used, and it is difficult to match perfectly. Not only this, but also the adjustment section becomes complicated.

The present invention aims to provide a pickup cartridge that provides even better braking effects in the low range even when a normal tone arm is used, without using a tone arm that has the drawbacks mentioned above, and its characteristics are as follows: However, a viscoelastic body and a suspension wire are provided between the power generating mechanism section of the cartridge and the cartridge support housing, so that the mass of the entire tone arm is used as an anti-resonance mass.

The details of the present invention will be explained below with reference to FIGS. 2 to 6.

FIG. 2 is a side sectional view of a cartridge showing an embodiment of the present invention, and shows an example of a moving coil type cartridge, in which a stylus 1 is fixed to the tip of a cantilever 2, and a coil is wound around the other end. Amateur 3 is fixed.

A center hole 4a is bored in the holder 4, a damper 5 is interposed between the armature 3 and the holder 4, the other end of a suspension wire 6 fixed to the terminal end of the cantilever is fixed to a suspension holder 7, and the suspension holder 7 is It is inserted into the center hole 4a of the holder 4 and fixed with a set screw 8.

Yokes 9a and 9b are arranged at both ends of the magnet 10, the cantilever 2 is inserted through a hole bored at one end of the yoke 9a, and the yoke 9b is held at one end of the holder 4 to hold the power generating mechanism section 11. It consists of

In the present invention, the yoke 9 constituting the power generation mechanism section 11
Drill a through hole 9c in the rear part of b, and insert the suspension wire 1
3 locked second suspension wire holder 1
6 into the through hole 9c and the center hole 4a of the holder 4,
It is fixed to the holder 4 with a set screw 17.

A nut for locking the other end of the suspension wire 13 to a third suspension wire holder 15 disposed on a support 18 fixed to the support casing 12 and adjusting the tension of the third suspension wire holder. have.

A damper material 14 is interposed between the yoke 9b and the support case 18, and the power generation mechanism 11 is connected to the support body 18 via the damper material 14.
A tension adjustment hole 12a is bored in the support casing 12, which is supported in a cantilever manner by the support casing 12.

The damper material 14 mentioned above can be made of butyl rubber, sponge-like rubber containing unvulcanized butyl rubber, or the like.

With the above configuration, the low frequency vibration characteristics of the tone arm can be expressed as shown in the equivalent circuit of FIG.

Here, 01 is the equivalent compliance of the needle tip consisting of the damper 5, etc. of the power generation mechanism 11, Ll is the equivalent mass of the magnet 10 and yokes 9a, 9b of the power generation mechanism 11, C2 is the equivalent compliance of the damper 14, and rice is the cartridge support. Equivalent mass of the entire tone arm including the housing 12, R
1 and R2 are equivalent resistances of the dampers 5 and 14.

That is, according to the equivalent circuit of the present invention, the above-mentioned equivalent mass can be used in place of the anti-resonance weight.

In such an equivalent circuit, in conventional braking using a tone arm, the ratio of the mass corresponding to the equivalent mass of the power generation mechanism 11 to the equivalent mass L2 of the entire tone arm is approximately 5:1, and the The response was as shown at the end of the low-frequency resonance frequency characteristic curve shown in the figure.

), the equivalent mass M2 of the rear counterweight part (
If the position (see FIG. 1) is moved away from the horizontal rotation axis position, the curve will be similar to the curve in FIG. 4, but in this case, the tracing ability will deteriorate in the low range due to the increase in the overall equivalent mass.

On the other hand, in the present invention, the ratio of both equivalent masses L1 and h is opposite to L
2 can be larger, and it can also be about 1:5.

Therefore, the characteristics can be better than those shown in FIG. 4-2.

FIG. 5 shows another embodiment of the present invention, in which the suspension wire 13 in FIG. 2 is replaced with a suspension ring 1.
3', the direction of rotation is fixed, and the entire power generation mechanism 11 is held elastically while always being held horizontally.

In either case, the vibration fulcrum of the suspension part is clear, and it almost coincides with the vibration direction of the vibration system of the power generation mechanism 11 at the needle tip, and does not vibrate in a different direction.
As shown by curves A' and 2' in the figure, crosstalk is also improved.

In the embodiment, it is held on the same axis as the pickup cantilever, but in the example shown in Fig. 2, the rear suspension is moved higher or the damper 14 is installed in a position closer to the generator mechanism 11.
Anywhere between the IJ joint support casings 12 may be used.

FIG. 6A shows another embodiment of the present invention of the moving magnet type, in which the damper 14 is made of ring-shaped butyl rubber and the suspension wire is omitted.

Further, the braking material 14a may be completely covered over the yokes 9a and 9b.

In addition, the damper 14 is replaced with the damper 5 of the power generating mechanism as shown in Fig. 4B.
It may be arranged in the peripheral area.

As mentioned above, in this invention, the power generation mechanism is cantilever-supported on the support case via the support body, so it is possible to effectively damp the low-frequency resonance, eliminate the peak of the resonance characteristics, and improve the tracing ability. cross-modulation due to vibration etc. is eliminated.
Crosstalk is also improved, and the sound quality is significantly improved.It is possible to use a general tone arm, and its practical effects are great.

[Brief explanation of the drawing]

Fig. 1 is a route diagram for explaining the low-frequency resonance of the tone arm, Fig. 2 is a partially sectional side view showing an embodiment of the present invention, and Fig. 3 is an equivalent circuit diagram of Fig. 2. , FIG. 4 is a low-frequency resonance characteristic curve diagram, FIG. 5 is an enlarged side view and front view of main parts showing another embodiment of the present invention, and FIGS. 6A and B are still other embodiments of the present invention. 1 is a side view and a sectional view of essential parts. 1... Needle tip, 2... Cantilever, 3
...Amateur, 5...Damper, 9
a, 9b... Yoke, 11... Power generation mechanism, 12... Cartridge support housing, 13...
...Suspension wire 14... Damper.

Claims (7)

[Scope of utility model registration request] (1) The power generation unit of the pickup cartridge, the power generation mechanism unit including the yoke and the magnet, is cantilever-supported on the pickup support casing via a damper material, so that the power generation mechanism unit has the equivalent mass of an anti-resonance type tone arm. A pickup cartridge featuring: (2) A utility model registration claim characterized in that the power generating mechanism section is cantilever-supported by being stretched in the same direction as the axial direction of a cantilever of a vibration system via a viscoelastic body in a cartridge support case. The pickup cartridge described in Scope 1. (3) When the power generation mechanism section is cantilever-supported on the cartridge support housing via a viscoelastic body, the power generation mechanism section vibration system is made more difficult to move in the direction perpendicular to the cantilever axis than in the direction of the cantilever axis. The pickup cartridge according to claim 1, wherein the pickup cartridge is cantilever-supported. (4) Utility model registration claim 2, characterized in that the power generation mechanism section is cantilever-supported by extending the power generating mechanism section to the cartridge support case via a viscoelastic body with a suspension wire.
Pickup cartridge as described in section. (5) The pickup cartridge according to claim 3, wherein the power generation mechanism is cantilever-supported by a suspension ring in a cartridge support housing via a viscoelastic body. (6) The pickup cartridge according to claim 1, wherein the power generating mechanism section is cantilever-supported on a cartridge support casing via an O-ring-shaped viscoelastic body. (7) A pickup cartridge according to claim 1, wherein the power generation mechanism is cantilever-supported by the cartridge support casing via a viscoelastic body at a coaxial position with the amateur support damper of the power generation mechanism. .