JPS6118801B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a tone arm braking mechanism using a braking fluid. In order to obtain good reproduction characteristics of a pickup 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 horizontal and vertical directions at the same time, but a two-point support type tone arm, such as a gimbal support type tone arm, suppresses resonance in both the horizontal and vertical directions. 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 has the disadvantage of increasing costs. Moreover, there was a great risk that the braking fluid would leak.

The present invention uses a single braking mechanism to
The present invention provides a tone arm braking mechanism that can not only suppress resonance in the vertical direction individually, but also suppress resonance in both directions simultaneously.

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 stand 2, and a first rotating body 3 that rotates in the horizontal direction is rotatably attached to the lower part of the shaft via a bearing as shown in the figure. provided. The first rotating body 3 is formed in a bowl-shaped recess, and an oil reservoir, which is a second rotating body to be described later, is disposed inside 31 thereof. For this purpose, a pivot shaft 4 is provided on one side 32 of the first rotating body 3, and a bearing that supports a rotating shaft 94 fixed to the oil reservoir is provided on the other symmetrical side 33. Further, the rotation shaft 94 protrudes to the vicinity of the stylus force adjustment knob 5 rotatably provided on the 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
A ring-shaped claw portion 62 is formed inside the end of the insertion tube 61 of the rotating shaft 1, and when the adjustment pilling 6 is press-fitted into the rotating shaft 1, the first cut groove 1 provided above the rotating shaft 1 is formed.
1, it comes into close contact with the rotating shaft 1 and does not rotate easily. The ring 6 is molded of synthetic resin or the like so that it can be pulled upward along the rotating shaft when braking is not required, and the pawl portion is connected to the second cut groove 12 provided above the cut groove 11 of the rotating shaft 1. jump in and stop. The ring 6 is provided with a circular groove 63 on the outer periphery of the insertion tube 61.
This space is used to house the inner circumferential wall of the oil reservoir of the rotating body. 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. 7 is the adjustment dial, the second
As shown in the figure, it is fitted into the ring 6, and a scale is provided on the inner periphery of the top. Adjustment dial 7
A circular groove 71 is also provided in the inner peripheral protruding wall 72.
is fitted into the outer circumferential wall of the circular groove 63 of the adjustment ring 6, and as shown in FIG. , 82 are inserted and engaged. 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 having a number of grooves 81 formed at its lower part, the inner circumference of which is fitted into the outer circumference of the inner protruding wall 72 of the adjustment dial 7, and a brake position adjustment pin 8 protruding inwardly.
2, 82 are the inclined grooves 73 of the adjustment dial 7,
73 and cut grooves 64 of the adjustment ring 6,
64 is inserted. Reference numeral 9 denotes an oil reservoir which is a second rotating body, and the oil reservoir is located on the outer periphery of the insertion tube 61 of the rotating shaft 1 and the adjustment ring 6 press-fitted therein. A circular groove 92 is formed for accommodating the oil reservoir body 91, and a bearing 93 is provided at the lower part thereof for receiving the pivot shaft 4 provided on the first rotating body 3 so as to support the oil reservoir body and rotate in the vertical direction.
A rotating shaft 94 that is fitted 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. Note that 96 is a cap screw for preventing the oil 91 from flowing out from the oil reservoir 9 during transportation.

When you want to make the braking in the horizontal and vertical directions larger or smaller than the state shown in the figure, when you turn the adjustment dial 7, the braking position of the brake ring 8 will be set in the inclined grooves 73, 73 provided on the inner peripheral protruding wall 72. Since the adjustment pins 82, 82 are inserted, the pins 82,
82 is the kerf 6 of the ring 6 within the slanted kerfs 73, 73.
4, 64 and change its position. Therefore, the brake ring 8 moves up and down as the position of the pin moves, and the cut groove 81 provided at the bottom of the ring moves.
The degree of immersion in the silicone oil 91 is changed, and the larger the immersed area, the greater the braking, and 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 adjustment ring 8 also moves to the inclined groove 77 of the adjustment dial 7.
Since it is inserted into the cut groove 64 of the adjustment ring 6 through the dial, it moves upward together with the dial 7,
The claw portion 62 comes off the first kerf 11 of the rotating shaft 1, jumps into the second kerf 12, and stops. At this time, the lower kerf 81 of the brake ring 8 moves above the silicone oil 91. It quickly stops coming into contact with silicone oil 91. Next, when horizontal vibration is applied to the rotary support portion of the tone arm, the first rotating body 3
The brake ring 8 rotates in the horizontal direction around the rotating shaft 1 together with the oil reservoir 9, which is a second rotating body supported by the pivot shaft 4 and the fixed shaft 94, and the brake ring 8 is immersed in silicone oil 91 so as not to cause any damage. Since it does not rotate, it will be subject to horizontal braking. Further, 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 has the configuration as detailed above,
As in the past, damping was applied to the rotational support of the tone arm separately in the horizontal and vertical directions to suppress resonance in each direction.
While it was not possible to sufficiently suppress resonance, in the case of tone arms supported at two points, damping in both the horizontal and vertical directions can be suppressed at once, as in the case of tone arms supported at one point. It is possible to sufficiently suppress resonance by using separate damping mechanisms. Furthermore, since it is possible to suppress resonance in both directions with just one oil reservoir, the structure of the tone arm braking mechanism can be simplified, making it a practically effective invention.

[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 a side view and a top view, respectively, of a brake adjustment ring, an adjustment dial, a control ring, and an oil reservoir according to the present invention. 1... Rotating shaft (main shaft), 3... First rotating body,
4... Pivot axis, 6... Brake adjustment ring, 62
...Claw part, 64 ... Cut groove, 7 ... Adjustment dial,
73... Inclined groove, 8... Brake ring, 82... Brake position adjustment pin, 9... Oil reservoir, 93... Bearing, 94... Fixed shaft, 95... Pipe mounting hole, 9
6...Cap installation screw.

Claims (1)

[Claims] 1. A bowl-shaped first rotating body 3 is pivotally supported on the rotation shaft 1 of the tone arm so as to be rotatable in the horizontal direction to control resonance in the horizontal direction, and a bearing mechanism 93 is provided on the side of the rotating body. , 94, the second rotary body 9 using a damping liquid 91 is pivotally supported on the first rotary body 3 so as to be rotatable in the vertical direction by the rotary shaft 1. Adjustment ring 6 tightly fitted above
The adjusting pins 82, 82 of the brake ring 8 are inserted into the inclined grooves 73, 73 provided opposite to the inner protruding wall 72 of the adjusting dial 7, which is rotatably provided, and then the circular grooves of the brake adjusting ring 6 are inserted. The adjustment pin is configured to be inserted into vertical grooves 64, 64 provided on the outer peripheral wall of the groove 63, and the adjustment dial 7 is rotated.
The tone arm is characterized in that by changing the position of the adjustment pin and changing the amount of immersion of the brake ring in the braking liquid, it is possible to control resonance even when both horizontal and vertical resonances are applied to the rotating shaft at the same time. Braking mechanism.