JPS6118802B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a tone arm braking mechanism using a damping liquid, and particularly to a tone arm damping mechanism that applies damping in the horizontal and vertical directions using one resonance suppressing means to suppress resonance. This relates to the braking mechanism of the tone arm.

To obtain good playback characteristics of the pick-up system,
It is necessary to apply damping in the horizontal and vertical directions to the rotary support portion of the tone arm to suppress resonance in each direction. In this case, conventionally there is a single-point support type pivot type tone arm that suppresses resonance in both the horizontal and vertical directions at the same time, but a two-point support type, for example, a gimbal support type tone arm, suppresses resonance in the horizontal or vertical direction respectively. Even if there is something that can suppress resonance independently, there has been no one that suppresses resonance in both directions at the same time. A structure that suppresses resonance in the horizontal and vertical directions independently requires two braking mechanisms, which complicates the structure and increases the number of parts, which also has the disadvantage of increasing costs. Furthermore, there was a great risk that the braking fluid would leak.

The present invention uses a single braking mechanism to
The tone can not only suppress resonance in the vertical direction individually, but also resonance in both directions at the same time, and is equipped with a brake liquid sealing device to prevent the brake liquid from leaking during transportation. This provides a braking mechanism for the arm.

An embodiment of the present invention will be described below with reference to the accompanying drawings. Reference numeral 1 denotes a rotating shaft (main shaft) of a rotary support portion of the tone arm, which is fixed to a tone arm fixing member 2 that is a stand, and a first rotating body 3 that rotates in the horizontal direction is provided with a bearing at the bottom of the shaft as shown in the figure. It is rotatably provided via the. The first rotating body 3 is formed in a bowl-shaped recess, and a second
An oil reservoir, which is a rotating body, is arranged. For this purpose, a pivot shaft 4 is provided on one side 32 of the first rotating body 3, and a bearing for supporting a rotating shaft 94 provided in the oil reservoir 9 is provided on the other symmetrical side 33. Furthermore, the rotating shaft 94 protrudes to the vicinity of the stylus force adjustment knob 5 rotatably provided on the other side portion 33. Note that the stylus force adjustment mechanism is not directly related to the present invention, so its details will be omitted. Next, the brake adjustment ring 6 is attached to the upper part of the rotating shaft 1 so as not to rotate. The ring 6 forms a ring-shaped claw part 62 inside the end of the insertion tube 61 of the rotating shaft 1, and when the adjusting ring 6 is press-fitted into the rotating shaft 1, the rotating shaft 1
It jumps into the first kerf 11 provided above and comes into close contact with the rotating shaft 1, making it difficult to rotate. The ring 6 is molded of synthetic resin or the like so that it can be pulled upward along the rotational shaft when braking is not required, and the claw portion is connected to the second kerf 12 provided above the kerf 11 of the rotational shaft 1. jump in and stop. Note that the ring 6 is provided with a circular groove 63 on the outer periphery of the insertion tube 61, which serves as a space for housing the inner circumferential wall of an oil reservoir of a second rotating body, which will be described later. Further, the outer peripheral wall of the circular groove 63 is provided with vertical grooves 64, 64, through which a brake position adjustment pin of a brake ring, which will be described later, is inserted, as shown in FIG. Reference numeral 7 denotes an adjustment dial, which is fitted into the ring 6 as shown in FIG. 2, and has a scale on the inner periphery of its top. The adjustment dial 7 is also provided with a circular groove 71, the inner peripheral wall 72 of which is fitted into the outer peripheral wall of the circular groove 63 of the adjustment ring 6, and inclined grooves 73, 73 are formed facing each other as shown in FIG. Manufacturers 82, 82, which will be described later, are inserted into the grooves. The circular groove 71 is a space in which a brake ring and an outer circumferential wall of an oil reservoir, which will be described later, are housed therein. Reference numeral 8 denotes a brake ring which has a number of cutting edges 81 formed at its lower part, and whose inner periphery is connected to the inner peripheral wall 72 of the adjustment dial 7.
Brake position adjustment pins 82, 82 which are fitted onto the outer periphery of and protrude inwardly are inserted through the inclined grooves 73, 73 of the adjustment dial 7 and into the grooves 64, 64 of the adjustment ring 6. There is. Reference numeral 9 denotes an oil reservoir which is a second rotating body, and this oil reservoir is connected to the rotating shaft 1.
It is located on the outer periphery of the insertion tube 61 of the adjustment ring 6 press-fitted therein, and its upper part forms a circular groove 92 for accommodating a braking liquid having viscous resistance, such as silicone oil 91, and its lower part supports an oil reservoir body. and a bearing 93 for receiving the pivot shaft 4 provided on the first rotating body 3 so as to be able to rotate in the vertical direction.
, and a rotating shaft 94 that fits into a bearing provided on the first rotating body 3 is provided at a position symmetrical to the bearing. Further, in the lower part of the oil reservoir, mounting holes 95, 95 are provided at positions perpendicular to the bearing 93 and rotating shaft 94 to which the tone arm pipe 97 and the weight shaft for supporting the weight are mounted. And the above-mentioned brake fluid 91, brake ring 8, adjustment dial 7
and the damping adjustment ring 6 form a resonance suppression means in phase relation. Reference numeral 96 denotes a screw for screwing together the cap 10 to prevent the oil 91 from flowing out from the oil reservoir 9 during transportation, and together they form a liquid sealing device for braking. Then, after leaving the damping liquid of the resonance suppressing means in the oil reservoir and removing the resonance suppressing means from the tone arm braking mechanism, the cap 10 is screwed onto the screw 96, and the silicone oil 91 is poured into the oil reservoir. can be sealed within the circular groove 62 of. 10' is a rubber packing to completely prevent oil leakage.

If you now want to make the horizontal and vertical braking larger or smaller than the state shown in the figure, by rotating the adjustment dial 7, the braking position adjustment pin of the brake ring 8 will be inserted into the inclined grooves 73, 73 provided on the inner peripheral wall 72. 82, 82 are inserted, so the pins 82, 82
are the kerfs 64 of the ring 6 within the slanted kerfs 73, 73,
64 and change its position.
Therefore, the brake ring 8 moves up and down as the position of the pin moves, changing the extent to which the cut groove 81 provided at the bottom of the ring is immersed in the silicone oil 91, and the larger the immersion area, the greater the braking effect. , the smaller the immersed area, the smaller the braking. When no braking is required, when the adjustment dial 7 is pulled upward, the position adjustment pin 82 of the brake ring 8 passes through the inclined cut groove 73 of the adjustment dial 7, and Since it is fitted into the groove 64, it moves upward together with the dial 7, and the claw portion 62 comes off the first cut groove 11 of the rotating shaft 1.
It jumps into the second kerf 12 and stops, and at this time the lower kerf 81 of the brake ring 8 moves above the silicone oil 91 and no longer comes into contact with the silicone oil 91. Next, when a horizontal vibration is applied to the rotary support portion of the tone arm, the first rotary body 3 is moved together with the oil reservoir 9, which is the second rotary body, which is supported by the pivot shaft 4 and the fixed shaft 94. Since the brake ring 8 rotates horizontally around the rotating shaft 1 and is immersed in silicone oil 91, it receives horizontal braking. Furthermore, when vertical vibration is applied to the rotation support section, only the oil reservoir 9 rotates in the vertical direction about the pivot shaft 4 and the fixed shaft 94 as rotation axes, and is subjected to vertical braking in the same manner as described above. Become. Therefore, in the above-described configuration, even if vibrations are applied to the rotary support in both the horizontal and vertical directions at the same time, the rotary support can receive braking in both the horizontal and vertical directions at the same time and in one oil reservoir.

Since the present invention is configured as detailed above,
Conventionally, damping was applied to the rotating support of the tone arm in the horizontal and vertical directions separately to suppress resonance in each direction, but resonance could not be suppressed sufficiently. In comparison, even in the case of a tone arm supported at two points, damping in both the horizontal and vertical directions can be applied by a single damping mechanism, as in the case of a tone arm supported at one point. was able to be sufficiently suppressed.
By simply removing the resonance suppressing means from the oil reservoir, which is the second rotating body, and firmly screwing the cap onto the outer peripheral wall of the oil reservoir, the leakage of braking oil from the oil reservoir can be completely prevented. Time,
It is possible to transport the braking oil while it remains in the oil reservoir without having to drain it from the oil reservoir each time, which is extremely convenient for handling.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a rotary support portion of a tone arm according to the present invention, FIG. 2 is an explanatory longitudinal cross-sectional view thereof, and FIG.
4, 5, and 6a and 6b are side and top views of the brake adjustment ring, adjustment dial, control ring, and oil reservoir according to the present invention, respectively, and FIG. 7 is a side view and a top view of the oil reservoir according to the present invention. FIG. 3 is a side view showing a state in which a cap is screwed onto an outer peripheral wall to seal braking fluid in an oil reservoir. DESCRIPTION OF SYMBOLS 1... Rotating shaft, 11... First kerf, 2... Tone arm fixing member, 3... First rotating body, 4
...Pivot axis, 6...Brake adjustment ring, 62...
... Claw portion, 64 ... Vertical cut groove, 7 ... Adjustment dial, 73 ... Inclined cut groove, 8 ... Brake ring, 81 ...
Cutting blade, 82...Brake position adjustment pin, 9...Second rotating body (oil reservoir), 91...Silicon oil, 93...Bearing, 94...Rotating shaft, 95...Mounting hole, 96... Cap installation screw, 10...cap.

Claims (1)

[Claims] 1. In a two-point support type tone arm, there is a brake adjustment ring 6 that is tightly fitted to the upper part of the rotation shaft 1 of the arm so as not to rotate, an adjustment dial 7 that is rotatably provided on the adjustment ring, and a brake liquid 91. An inclined cut groove 73, which is immersed and whose adjustment pins 82, 82 are provided in the inner circumferential wall 72 of the adjustment dial 7,
73 and is further inserted into the cut grooves 64, 64 of the adjustment ring 6, the resonance suppressing means consisting of the brake ring 8, etc. is pulled out above the rotating shaft 1, and the oil reservoir 9 containing the brake liquid 91 is pulled out. A tone arm braking mechanism characterized in that a cap for preventing the braking fluid from flowing out is screwed onto the tone arm to seal the braking fluid.