JPS6237443B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a tone arm drive device for a record player.

In general, a tone arm drive device uses a gear train to reduce the rotational speed of a motor to raise, lower, or rotate the motor, or utilizes the rotational force of a turntable to raise, lower, or rotate, and uses the motor or turntable as its driving source. Since it uses rotational force,
Problems arise in that the coupling mechanism between the drive source and the tone arm becomes complicated and assembly becomes difficult.

The present invention eliminates such conventional drawbacks, and the present invention will be described below with reference to drawings of embodiments.

1 and 2 show an embodiment of the present invention, in which 1 is a tone arm, a pickup cartridge 2 is attached to its tip, and a balance weight 3 is attached to its rear end. There is. The tone arm 1 has a mounting portion 4 at the rear of the center thereof, and the mounting portion 4 is connected to a vertical shaft 5.
It is supported by a horizontal shaft 7 on a pedestal 6 installed in the
On the other hand, since the vertical shaft 5 is supported by a bearing 8, it can freely rotate in the direction of the arrow E-L in the figure.
It is also configured to be able to freely move up and down in the direction of the arrow shown in the figure. The tone arm 1 is controlled to move up and down and rotate with respect to a record disc 11 on a turntable 10 which is rotated in one direction by a rotation shaft 9. Reference numeral 12 designates a lift arm for raising the tone arm 1 from the illustrated armrest position and lowering it from the raised position to the armrest position, and is supported on a bearing 13 so as to be able to move up and down. A lift shaft 4 is coupled. The bearings 8 and 13 are attached to a panel 15 of the main body of the record player. 16
is a turning plate for turning the tone arm 1 from the raised position of the armrest to the playing start position of the record disc 11, or for turning the tone arm 1 from the playing end position of the record disc 11 to the raised position of the armrest; It is connected to the shaft 5.
A connecting pin 17 is provided on the rotating plate 16. Reference numeral 18 denotes a drive device main body associated with the lift shaft 14 and the connecting pin 17, and a mounting portion 19 integrally provided on the panel 15.
A frame 20 fixed to and this frame 20
an electromagnet 21 fixed to a hollow rotating shaft 20a provided in the hollow rotating shaft 20a; a cup-shaped rotating plate 23 attached to a rotating shaft 22 rotatably inserted through the hollow rotating shaft 20a; A rotor magnet 24 fixed to the inner peripheral surface of 23 and the frame 20
A braking member 25 is provided between the rotating plate 23 and the rotating plate 23. Here, the rotating plate 23 is integrally provided with arm elevating cams 26a and 26b on its upper surface, with which the lower end of the lift shaft 14 comes into contact, and also makes contact with a connecting pin 17 provided on the rotating plate 16. Engaging protrusions 27a and 27b that come into contact with each other are integrally provided. Further, the electromagnet 21 is attached to the frame 20.
Terminal pins 28a and 28b are provided to which the coils are connected. The electromagnet 21 has coils 30a and 30 attached to each leg portion 29a and 29b of a laminate core 29, which is formed by laminating a large number of V-shaped magnetic plates.
b is wound, and the starting and ending ends of the coil winding are connected to terminal pins 28a and 28b, respectively. In these coils 30a, 30b, magnetic fields of different polarities are generated at the tips of the respective leg portions 29a, 29b according to the polarity of the applied voltage, and the magnetic coupling with the rotor magnet 24 is changed. Ru. The rotor magnet 24 has an arc shape and is magnetized at both ends thereof. And the electromagnet 2
When 1 is not energized, one leg 29
a is located at the neutral position of the rotor magnet 24. The braking member 25 is made of a bellows-shaped air bag that is expandable and retractable, and has a small hole 25a at one end for adjusting the amount of air flowing in and out. This braking member 25 has one end attached to the frame 20.
The other end is attached to the mounting piece 20b provided on the rotating plate 23.
They are each fixed to mounting pieces (not shown) provided on the inner surface of the. In addition, in the figure, 31 is the above-mentioned rotating shaft 2.
This is the E-ring to prevent the item from falling off.

In the tone arm drive device having such a configuration, when the start button is operated to apply a voltage of a certain polarity to each coil 30a, 30b of the electromagnet 21, the magnetism between the electromagnet 21 and the rotor magnet 24 is activated. In this relationship, the rotor magnet 24 rotates in the direction of the arrow H in the figure, and in response to this movement, the rotating plate 23 also rotates in the direction of the arrow H in the figure. When the rotary plate 23 rotates in the direction of arrow H in the figure, the lower end of the lift shaft 14 comes into contact with the inclined surface of the arm elevating cam 26a and is raised in the direction of arrow C in the figure by the lift arm 12. The tone arm 1 is raised in the direction of arrow C in the figure. When the tone arm 1 reaches the raised position of the armrest, the lower end of the lift shaft 14 is moved to the arm lifting cam 26a.
Since the tone arm 1 comes into contact with the plane of the electromagnet 21, there is no further upward movement of the tone arm
Since the energization is not released, the rotor magnet 24 continues to rotate in the direction of the arrow H in the figure. As the rotor magnet 24 continues to rotate in the direction of arrow H in the figure, the rotary plate 23 continues to rotate, so that the engaging protrusion 27a provided on the rotary plate 23 comes into contact with the connecting pin 17. As a result, the tone arm 1 pivots in the direction of arrow A in the figure from the raised position of the armrest. During the rotation of the rotating plate 23 in the direction of arrow H in the figure, the braking member 25 provided between the rotating plate 23 and the frame 20 is compressed, so that the tone arm 1
The upward movement and rotational movement of the tone arm 1 move slowly, and do not impede the movement of the tone arm 1 in any way. Next, when the tone arm 1 is moved to the playing start position of the record disc 11 by the above-mentioned turning movement, in order to detect this position and de-energize the electromagnet 21, the turning plate 23 is rotated in the direction of the illustrated arrow. That is, when the magnetic coupling force between the electromagnet 21 and the rotor magnet 24 disappears, the rotating plate 23 slowly rotates in the direction of the arrow shown in the figure due to the return force of the braking member 25. In response to this movement, the lift shaft 14 is lowered in the direction of the arrow N shown in the figure, and the pick-up cartridge cartridge 2 provided at the tip of the tone arm 1 is lowered to the playing start position of the record disc 11.
Then, the rotating plate 23 will be stopped when the braking member 25 returns to its original state,
The tone arm 1 is placed in a freely rotating state. In this way, the lead-in operation of the tone arm 1 is completed.

On the other hand, when the pick-up cartridge 2 provided at the tip of the tone arm 1 reaches the end position of the record disc 11, this position is detected and a voltage of opposite polarity to that in the lead-in operation is applied to the electromagnet 21. be done. Then, due to the magnetic relationship between the electromagnet 21 and the rotor magnet 24, the rotor magnet 24 rotates in the direction indicated by the arrow in the figure, so that the rotary plate 23 rotates in the same direction. When the rotary plate 23 rotates in the direction indicated by the arrow, the lower end of the lift shaft 14 comes into contact with the inclined surface of the arm elevating cam 26b, and is raised by the lift arm 12 in the direction indicated by the arrow C. The tone arm 1 is raised in the direction of arrow C in the figure at the end position of record playing.
When the tone arm 1 reaches the end position of the record playing and fully rises in the direction of the arrow C in the figure, the lower end of the lift shaft 14 reaches the arm elevating cam 2.
6b, the tone arm 1 no longer moves upward; however, since the electromagnet 21 is not de-energized, the rotor magnet 24 continues to rotate in the direction of the arrow shown in the figure. As the rotor magnet 24 continues to rotate in the direction of the arrow shown in the figure, the rotating plate 23 continues to rotate, so that the engaging protrusion 26b provided on the rotating plate 23 connects the rotating plate 16. Due to the contact with the pin 17, the tone arm 1 pivots in the direction of arrow B in the figure from its raised position at the end of record playing. During the rotation of the rotation plate 23 in the direction of the arrow shown in the figure, the braking member 25 provided between the rotation plate 23 and the frame 20 is extended, so that the upward movement and rotation movement of the tone arm 1 are prevented. Make slow movements and press the tone arm 1 above.
There will be no hindrance to the transportation of Next, when the tone arm 1 is moved to the raised position of the armrest by the above-mentioned turning movement, this position is detected and the energization to the electromagnet 21 is canceled, so that the turning plate 23 moves as indicated by the arrow in the figure. It will be rotated in the E direction. That is, when the magnetic coupling force between the electromagnet 21 and the rotor magnet 24 disappears, the rotating plate 23 slowly rotates in the direction of the arrow H in the figure due to the return force of the braking member 25. In response to this movement, the lift shaft 14 is lowered in the direction of the arrow D shown in the figure, and the tone arm 1 is lowered.
will be lowered to the armrest position.
Then, the rotating plate 23 is stopped when the braking member 25 returns to its original state.
The tone arm 1 is placed in a stopped state. In this way, the return operation of the tone arm 1 is completed.

As described above, according to the present invention, the arm elevating cam associated with the lift shaft for elevating and lowering the tone arm and the engaging protrusion associated with the rotating plate for rotating the tone arm are provided. A rotor magnet is provided on the formed rotating plate, an electromagnet for driving the rotor magnet is provided on a frame that supports the rotating plate, and a braking member is provided between the frame and the rotating plate. By simply applying voltages of different polarities to the electromagnets, the magnetic relationship between the electromagnets and the rotor magnets can be changed to rotate the rotary plates in opposite directions, thereby causing the braking member to rotate with the frame. By providing it between the moving plates, the tone arm can be moved while appropriately controlling the rotational speed of the rotating plates. As described above, the present invention can provide a tone arm drive device with a simple structure and reliable operation.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an embodiment of the tone arm driving device of the present invention, FIG. 2 is a sectional view of a main part of the same device, and FIG. 3 is an assembled perspective view of a main part of the same device. 1...Tone arm, 12...Lift arm,
14... Lift shaft, 16... Swivel plate, 17... Connection pin, 18... Drive device main body, 20... Frame, 21... Electromagnet, 22... Rotating shaft, 23...
Rotating plate, 24... Rotor magnet, 25... Braking member, 26a, 26b... Arm lifting cam, 2
7a, 27b...Engaging protrusion pieces.

Claims (1)

[Claims] 1. A rotor magnet is attached to a rotating plate formed with an engaging protrusion associated with a lifting cam associated with a lift shaft for vertically moving the tone arm and a rotating plate for rotating the tone arm. and an electromagnet for driving the rotor magnet is provided in a frame that supports the rotating plate, and a braking member is provided between the frame and the rotating plate, and voltages of different polarities are applied to the electromagnet. 1. A tone arm drive device for a record player, characterized in that the tone arm is configured to move up and down and rotate by rotating rotating plates in opposite directions.