JPS58194178A - Pickup - Google Patents

Abstract

PURPOSE:To decrease a noise level generated in an audio band, by approaching a position of a stylus tip in contact with the surface of an electrostatic capacity type video disc to the 1st virtual line prolonged toward the direction of arm extension and suppressing the vibrating component from the stylus affected on the specific resonance of a stylus holder. CONSTITUTION:A sytlus holder 5 is formed with a synthetic resin and consists of a base section 51 led to an arm 4 and the center line of which is almost coincident with the 1st virtual line 9, a through-hole 55 through which the stylus 6 is inserted and held, a stylus support section 54 whose center line is almost coincident with the 1st virtual line 9, and a bridge 56 connecting the base section 51 and the stylus support section 54. The bridge 56 has a flat section 56a, a front slope 56 tilted and led to the surface of the stylus support section 54 and mounting the middle part of a fly lead 7 additionally, and a rear slope 56c placed at the opposite side of the slope 56b, and is provided with a recess 57 to decrease the weight of the stylus holder 5. In the pickup having the stylus holder like this, since a contact point P is approached to the 1st virtual line 9, the frequency characteristics of the audio band at reproduction are improved without changing other characteristics.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a video disk that is applied to an electrostatic video disc player, and mainly relates to an F! jl Improving wavenumber characteristics? This is the purpose.

Figure 1 shows a schematic configuration diagram of a pickup applied to a conventional CED type player. In the same figure, (1) is a pickup case, +2
) (31 is I[1, second support, (4) is A-A, +5
) is a needle supporter, (6) is a stylus, and (7) is a fly lead. The I8181 support 2) is supported by the pickup case (1) and engages with an arm stretcher (not shown), so that the stylus (1) can be attached to the arm stretcher.
6) mainly in the direction of the first axis axis 18) so as to hang I
I have been created. The second support (3) is a stylus (6)
One end surface is fixed to the first support body (2), and the other end portion has an arm (4) penetratingly supported therein. The arm (4) is made of aluminum and formed into a tube shape, and one end of the arm (4) is made of aluminum.
1,112 support (21 (31) is elastically supported by the pickup case; 1).
) is supported through the needle support (5).

Needle support @ (51 is wood qti + molded, arm (
4), the base (51) supported by the fly, and the lead (7).
), and a needle support part (father) that holds the stylus (6). ) is a through hole provided in a direction intersecting the I11 imaginary line (9), which corresponds to the extending direction of the I11 line (9). The stylus (6) has a tip that contacts the video disc and a base that is attached to the needle support (54), and is provided with electrodes (not shown) on the surface of the steel that runs against the video disc. Fly lead (7)
) is an elastic metal plate. One end is supported by the big acupuncture case 111, the other end is connected to the electrode of the stylus (6), and the middle part is connected to the slope (52) of the needle supporter (5). It is installed so that it is attached. This fly lead (7) maintains smooth tracking of the stylus and applies appropriate stylus pressure (= regeneration circuit (v!J not shown)).
Serves as an output lead to.

111 Intersection angle of temporary flow line (9) with respect to video disc (
α) is set in the range of 4 to C, preferably 5', mainly to ensure compatibility with the video disc of the pickup. Further, the distance Q between the contact point and the @1 virtual ring (9) is approximately 1.4 to 1.811 Im. For example, a video disc with a speed of 450 quadruple revolutions per minute (with an unmodulated track for testing and an IK
't'r 97 ('716 KHz) in Hz 50
When the audio output terminal was played back with a long modulation and an A-key track, the noise level vs. frequency characteristic shown in Figure 112 was observed at the audio output end.

This shows the reproduction characteristics of an unmodulated track when the spectrum analyzer input after reproducing the modified track is OdB and [-1]. As a result of careful consideration, the longitudinal and yI torsional vibration resonances of the pickup perturbation thread are as follows.
50#z and 1f311z, respectively, and the resonance of the vibration system of the second support and the arm is near IQ#z, and I: 12 to 1Af recognized in Figure 2.
It has become clear that the resonance near Hz is mainly caused by the resonance of the arm (4) (this is due to this), and M! The unnecessary noise in appendix i occurs when the stylus (6) receives an impact from the video disc, and this impact is transmitted to the stylus (16), which is made of a rigid body like a diamond, and then the vibration is transmitted to the adjacent needle support (5). It is a needle support device.

Figure 3 shows the contact points (
This shows the force relationship with respect to Pl. The force F is considered to be decomposed into a component Fse along the $1 imaginary line (9) and a component F perpendicular to this, of which the component Fy acts as an impulsive force that is involved in the generation of the above-mentioned unnecessary noise.

Here, the first virtual! If θ is the angle made with respect to the second imaginary line Ill connecting the fulcrum surface and the contact point [F] in (9), then F/
=tmta milk θ, yx, and if Fxt is constant, it can be seen that reducing the intersection angle O helps to eliminate the impact force. Furthermore, it is possible to eliminate the component Fy by arranging the contact point on the 111 virtual line (9), but this is practically impossible considering the engagement with the video disc.
(for example, the needle support comes into contact), it is desirable to bring the contact point as close to the first imaginary line (9) as possible. Keeping F-x constant, the angle θ' is smaller than the angle table.
By setting the component Fy to a smaller component Fy', the impact force on the needle supporter (5) can be reduced, thereby reducing unnecessary noise components caused by this. Become.

The present invention has been made in view of this point, and is achieved by bringing the tip of the stylus that contacts the disk surface during playback closer to the first temporary line extending in the direction in which the arm extends.
This invention provides a pickup for suppressing the vibration component from the stylus that affects the solid a resonance of the needle support, thereby reducing the noise level generated in the vocal range.

The present invention will be explained below based on Examples. Figure qL/1 shows an outline of the main parts of an embodiment of the present invention, in which figure a is a side view and figure a is a perspective view (1FIZ). This remarkable difference compared to the conventional example of the present invention is due to the structure of the needle supporter).
Other configurations can be the same as those in Figure @1, so 75 parts of arm (4) and fly lead (7) can be used.
etc. are omitted from the illustration for the sake of simplicity.

In Figure 1, the same figure number as Figure 111 indicates the same functional element.
~ing.

The needle supporter (5) is molded by synthetic atomization +1,
Continuing with the arm (4), the center line of the above @1 imaginary line 19) has a base (51) which is approximately bent, and a through hole (55) through which the stylus (6) is passed and held. , and a bridge (56) that extends between the needle support part (5J) j-base (51) and the needle holding part CFA'') whose center line approximately coincides with the 1 tack line (9). It is composed of.
The bridge (56) includes a flat part (56a) and a fly lead (7) extending obliquely to the surface of the needle support part (shi).
The needle supporter 15 is provided with an auxiliary slope (56) to which the intermediate part of the needle supporter 15 is attached, and a rear slope (560) on the opposite side.
1 part (7) is provided to reduce the weight l of 1.

fJ) Since the pickup of the present invention having such a needle supporter can be used, it is possible to improve the frequency characteristics of the vocal band during playback without changing other characteristics. @
Figure 5 shows the frequency characteristics in this example.
The distance from the first temporary line ('9) to less than half that of the conventional example (n
, 5 to 0.7 m).

Noise around 12 to 13 KHz can be reduced by 6 to 8 dB, and good sound quality can be obtained due to flat noise wave number characteristics.

Figure 11G6 shows a needle supporter according to another embodiment of the invention.C
In both cases, the bridge is formed in an arc shape [Tamonode I], and in bC, the bridge is formed in a V-shape. In each example, the needle support part is arranged on the first imaginary line (9) and the needle so that the intersection angle θ between the first imaginary line (one) and the second imaginary line 01 is small. By reducing the width of the unique vibration that occurs in the wave holder 151, the noise level that increases as the number of multiple waves increases is suppressed.

[Brief explanation of the drawing]

Figure 1 shows an outline of a conventional pickup! y, figure, broom 2
The figure shows the frequency dispersion characteristic haze of the noise level in this pickup. Fig. 3 is an explanatory diagram of the joint movement of the needle supporter; Figs. 11 and 4 are main part configuration diagrams of the pickup of the present invention; It is a w4 wave number characteristic diagram of the noise level of the pickup shown in the figure. $
Figures 6a, 6h and 6a are all side views of needle supports according to other embodiments of the present invention. Explanation of main drawing numbers (1)...Case 7, (4)...Arm, (5)...
... Needle supporter, (6) ... Stylus, (7) ...
Fly lead, +91-...111 provisional filli-(1
1... 2 virtual mats.・Mi-2

Claims (1)

[Claims] A case, an arm whose one end is elastically supported by the case, a needle support fixed to the free end of the arm, and a first imaginary line that corresponds to the extending direction of the arm. a stylus disposed in a stylus support portion of a pointing needle supporter so as to protrude in a crossing direction; one end supported by the case, the other end connected to the stylus, and an intermediate portion connected to the needle supporter; In a pickup equipped with an attached fly lead, the needle support part of the needle supporter is connected to a first imaginary line, a fixed point of the needle supporter to the arm, and a contact point of the stylus to the recording medium I: A pickup characterized in that the pick-up is arranged on the @1 imaginary line so that the angle of intersection with the connecting @2 imaginary line is small;