JPS6059641B2 - Tone arm mounting device - Google Patents

Description

[Detailed description of the invention] The present invention relates to improvements in tone arm mounting devices.

In order to isolate the tone arm of a record player from vibrations from an enclosure (cabinet), etc., there is a conventional method of encasing the entire mounting portion of the tone arm with rubber.

This has a low-frequency cut-off characteristic due to the compliance of the rubber, but if it has the compliance to cut off even the low-frequency range, it becomes quite soft, and therefore requires detection engineering in the front-rear direction of the needle tip. , is absorbed in this part, and as a result, the low frequency reproduction level is impaired.
Furthermore, the reproduction of pulse components will lack fidelity. Therefore, in this method, a specific compliance is selected and carried out, but the intended effect cannot be fully achieved. The present invention focuses on these points,
The tone arm mounting part has high compliance in the vertical direction and high rigidity in the front and back directions of the arm, making it possible to isolate external vibrations without adversely affecting playback characteristics. The aim is to provide equipment.

Hereinafter, one embodiment will be described with reference to the drawings. Reference numeral 1 denotes an arm body, which is attached to an arm stand 2 by a flexible assistant 8. This arm stand 2 is fitted and fixed by a mounting screw 3 to a stand column 4 having fins 4a formed on its outer periphery at appropriate intervals. On the other hand, 6 is a stand base fixed to the enclosure 7, and this stand base 6 also has fins 6a formed on its inner periphery at appropriate intervals. And these stand props 4
and the stand base 6 are arranged in a fitted state so that the fins 4a and 6a are alternately facing each other, and this arrangement state is made of a pair of rings made of metal or resin with a corrugated cross section. The bellows 5 are held by connecting the inner circumferential edge of each bellows 5 to the outer circumference of the stand support column 4 and the outer circumferential edge to the stand base 6 at vertically spaced positions.

It should be noted that the arm stand 2 and stand column 4 constitute a support member for the tone arm 1, and the stand base 6 constitutes a base member. With the inner peripheral edge and the outer peripheral edge connected to the support member and the base member, respectively, as described above,
The bellows 5 has high compliance in the vertical direction, that is, in the axial direction of the stand support 4, and has rigidity in the lateral direction, that is, in the axial radial direction of the stand support 4.

Note that a viscous fluid such as silicone oil is sealed between the upper and lower bellows 5 to lower the Q at the time of resonance in the vertical direction.

In other words, even if the resonance frequency determined by the weight of the tone arm 1 and the compliance of the bellows 5 is selected to be a frequency that can block vibrations transmitted from the enclosure part, resonance may occur. In this way, lower the Q.

In this case, a vibration resistor such as rubber may be attached to the bellows 5 without using the viscous fluid. From the above, the arm mounting portion seen from the tip of the tone arm has high rigidity, and also greatly absorbs floor vibrations.

For this reason, firstly, the howling margin increases, secondly, cross-modulation distortion in the middle and high ranges decreases, and thirdly, there is less cancellation due to the phase difference in the low-frequency range, which improves the level of the low-frequency range and produces heavy bass. Fourthly, the transient characteristics are better than when the whole thing is covered with rubber, and fifthly, the S/N is better because the rough vibrations of the motor are absorbed.
Sixth, if the resonant frequency is selected so that the entire tone arm acts as a high absorber for the enclosure, howling characteristics can be greatly improved.

Note that the illustrated fins 4a and 6a may be continuous in the circumferential direction, but in this case, they are preferably spirally shaped to facilitate assembly.

Also, if the fins are provided vertically or in a wavy shape,
It can also help control the direction of the tone arm.

[Brief explanation of the drawing]

The figure is an explanatory view of a main part sectional view for explaining one embodiment of the present invention. 2...Arm stand, 4...Stand support, 5...Bellows, 6...Stand base.

Claims (1)

[Claims] 1. In a tone arm mounting device for a record player, the inner peripheral edge is attached to the outer periphery of the support member that supports the tone arm.
a pair of cross-sectional waveforms each having a large compliance in the axial direction of the supporting member and rigidity in the axial radial direction of the supporting member by respectively connecting the outer peripheral edges to a base member disposed concentrically on the outside of the supporting member; A tone arm mounting device characterized in that the tone arm is supported on a support member via a ring-shaped bellows.