JPS6235122Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a tone arm drive device for a record player, and in particular, it is an object of the present invention to provide a tone arm drive device that can horizontally rotate and move the tone arm up and down with a simple structure. It is. 2. Description of the Related Art Automatic record players that can perform automatic lead-in and automatic return are known. The automatic record player can bring the tone arm from a non-performance position to a performance position, or from a performance position to a non-performance position, simply by operating an operating knob. This was done using the rotational force of a motor to rotate the turntable. In such a device, since the driving force can be shared, the cost can be reduced, but special measures must be taken to make the driving force shared. This has the disadvantage that the operation becomes unstable, and there is a risk that the rotation of the turntable in particular may be adversely affected. Therefore, in recent years, record players have been proposed that are equipped with a motor separate from the motor for driving the turntable, and in which a tone arm is driven exclusively by the separate motor, and have come into practical use. The present invention relates to a tone arm driving device in which the tone arm is driven exclusively by the above-mentioned separate motor, and will be described below based on an embodiment with reference to the drawings. Figure 1 is a side view showing one embodiment of the present invention;
The figure is a partial plan view, and Figure 3 is a back view.
2 is a tone arm equipped with a record stylus (not shown) at the tip; 2 is an arm base that rotatably supports the tone arm 1; 3 is a support arm for vertically moving the tone arm 1; 4 is the tone arm. 1 is a control plate fixed to the rotating shaft 5; 6 is a drive motor rotatable in both directions for driving the tone arm;
7 is a first pulley fixed to the shaft 8 of the drive motor 6; 9, the rotation of the drive motor 6 is connected to the first belt 1;
0, 11 is the second pulley
a third pulley fixed to the rotating shaft 12 of the pulley 9;
13 is a fourth pulley to which the rotation of the third pulley 11 is transmitted via a second belt 14 made of a resilient material such as rubber; 15 is a fourth pulley to which the rotation of the fourth pulley 13 is transmitted via a friction plate 16; The lifting cam has a flat cam part 17 and a side cam part 18, and 19 is a rotating shaft 2 provided at one end so as to be able to swing within a predetermined range.
0 is a swinging plate pivotally supported on a base plate 44; 21 is a drive shaft extending from the rotating shaft 12 of the second pulley 9; 22 is a drive shaft provided on the swinging plate 19 and connected to the drive shaft 21; and a bearing that rotatably supports the rotating shafts 12 of the second and third pulleys 9 and 11;
23 is a friction rubber disposed at one end of the control plate 4, and 24 is a movable iron core 2 that is attracted by energization.
This is a plunger in which a pressing plate 45 is fixed to 4a. By the way, the swing plate 19 is connected to the plunger spring 2.
7, the pressing plate 45 is biased in the opposite direction of arrow B.
As shown in the partial perspective view of FIG.
The end opposite to the rotating shaft 20 which is supported by the rotary shaft 20 is pressed, and the drive shaft 21 is displaced to the first position (the state shown in FIG. 3) where the drive shaft 21 is spaced apart from the friction rubber 23. When the swing plate 19 energizes the plunger 24 to attract the movable core 24a and release the urging force applied to the swing plate 19 by the press plate 45, one of the swing plates is pivoted on the swing plate 19. The tension of the second belt 14 stretched over the third pulley 11 rotates around the rotation shaft 20, and the drive shaft 21 is displaced to the second position where the drive shaft 21 is brought into contact with the friction rubber 23. Next, the operation will be explained. In the case of automatic lead-in, when the drive motor 6 is rotated in the direction of arrow A in FIG.
The second pulley 9 connected through 0 also rotates in the direction of arrow A. Furthermore, the third pulley 11 fixed to the rotating shaft 12 of the second pulley 9 also rotates in the direction of arrow A, and the rotation is transmitted to the fourth pulley 13 via the second belt 14, and the fourth pulley 13 also rotates. Rotate in the direction of arrow A. Therefore, the cam 15 frictionally engaged with the fourth pulley 13 via the friction plate 16 rotates in the direction of arrow A, and the support arm 3, which has a lower end that comes into contact with the planar cam portion 17 of the cam 15 , rotates in the direction of the arrow A. Planar cam part 17
As the tone arm 1 rises, the tone arm 1 is brought to the highest position. At this time, the cam 15 is provided with a locking protrusion 25, and when the cam 15 rotates by a predetermined angle, the protrusion 25 is locked with a locking part 26 provided on the arm base 2. It is configured to prevent the cam 15 from rotating. In this state, the cam 15 and the fourth pulley 13 slip, the fourth pulley 13 rotates, and the cam 15 stops. And cam 1
5 is stopped, the support arm 3 and tone arm 1 are maintained at the highest position. When it is confirmed that the tone arm 1 has finished rising, the plunger 24 is excited, and the swing plate 19 is urged in the direction of arrow B by the plunger 24. When the plunger 24 is not biased, the rocking plate 19 is biased in the direction opposite to the arrow B by the force of the plunger spring 27 and is in the first position; however, when the plunger 24 is attracted, The biasing force of the plunger spring 27 is released, and the rocking plate 1
9 is biased in the direction of arrow B by the tension of the second belt 14 and enters the second position state. Therefore, the drive shaft 21 extending from the rotating shaft 12 of the second pulley 9 is frictionally engaged with the friction rubber 23 disposed on the control plate 4.
The control plate 4 rotates in the direction of arrow C in FIG. 3 in response to the rotation of the drive shaft 21 in the direction of arrow A, and the tone arm 1 also rotates in the direction of arrow C. When the tone arm 1 rotates by a predetermined angle, that is, when the introduction groove of the record is detected by a separate detection means and the record needle is positioned above the introduction groove of the record, the excitation to the plunger 24 is released and the plunger The biasing force of the spring 27 biases the rocking plate 19 in the direction opposite to arrow B and returns to the first position. Therefore, the engagement between the drive shaft 21 and the friction rubber 23 is released, and the horizontal rotation of the tone arm 1 is stopped. When the horizontal rotation of the tone arm 1 stops, the drive motor 6 starts rotating in reverse. The first pulley 7, second pulley 9, third pulley 11, and fourth pulley 13 each rotate in the opposite direction of arrow A, and the cam 15 frictionally engages with the fourth pulley 13 via the friction plate 16. Rotate in the opposite direction of arrow A and attach support arm 3.
Then, the tone arm 1 is lowered and the performance begins. When the planar cam portion 17 of the cam 15 is in the lowered position, it has a first arm 28 that contacts the side cam portion 18 of the cam 15 and a second arm 30 that controls the contact point of the micro switch 29. The second arm 30 of the control member 32 which rotates presses the contact point of the micro switch 29, and a signal indicating that the tone arm 1 is in the lowered position is generated from the micro switch 29. When a signal is generated from the micro switch 29, the current supplied to the drive motor 6 is cut off, and the drive motor 6 stops rotating. The above is the operation of auto lead-in. Next, auto-return will be explained. As the performance of the record progresses and the record needle reaches the final silent groove of the record, a current of opposite polarity to that during auto lead-in flows through the drive motor 6, and the first pulley 7 rotates in the direction opposite to arrow A. Therefore, the second pulley 9,
Pulley 11 and fourth pulley 13 also rotate in the opposite direction to arrow A, and cam 15 also rotates in the opposite direction to arrow A. The cam 15 is configured such that the planar cam portion 17 reaches the raised point no matter which side it rotates from. As a result, the rotation of the cam 15 causes the support arm 3 and the tone arm 1 to reach the raised position. It is maintained. As explained at the time of auto lead-in, the cam 15 is configured to stop rotating at a predetermined position. Tone arm 1 is rotated by rotation of cam 15 .
When it is confirmed that the plunger has reached the raised position, an exciting current is applied to the plunger 24, and the swing plate 19
is driven in the direction of arrow B, and the swing plate 19
position to reach the second position. Therefore, the friction rubber 23 of the drive shaft 21 and the control board 4
When the drive shaft 21 rotates in the direction opposite to the arrow A, the control plate 4 and the tone arm 1 move in the direction of the arrow C.
The tone arm 1 is rotated in the opposite direction, and the tone arm 1 is returned. When the tone arm 1 reaches the rest position, it is detected that the tone arm 1 has reached the rest position, and the supply of excitation current to the plunger 24 is stopped. Therefore, the swing plate 19 moves in the direction opposite to arrow B, and the horizontal rotation of the tone arm stops. At the same time, the drive motor 6 rotates in reverse, and the first, second and third
The fourth pulleys 7, 9, 11 and 13 rotate in the direction of arrow A, and the cam 15 also rotates in the direction of arrow A, so the support arm 3 and tone arm 1 descend,
When the lowered position is reached, the rotation of the drive motor 6 is stopped by the action of the micro switch 29. The above is the auto return operation. As is clear from the above description, according to the present invention, the rotation of the drive motor 6 is transmitted to the fourth pulley 13 via the second belt 14, and further converted into vertical force by the cam 15 . , the tone arm 1 can be reliably raised and lowered. Further, according to the present invention, the second
Since the belt 14 uses its elasticity to urge the swinging member 19 on which the second and third pulleys 9 and 11 are rotatably mounted, the drive shaft 21 and the friction rubber 23
This has the advantage that the tone arm 1 can be freely rotated in a desired direction, and that no special means for urging the rocking plate 19 is required.

[Brief explanation of the drawing]

FIG. 1, FIG. 2, FIG. 3, and FIG. 4 are a side sectional view, a top view, a back view, and a partial perspective view, respectively, showing an embodiment of the present invention. Explanation of main drawing numbers, 1...Tone arm, 6...
Drive motor, 7, 9, 11, 13...Pulley, 1
0, 14...Belt, 15 ...Cam, 21...Drive shaft, 23...Friction rubber.

Claims (1)

[Scope of utility model registration request] A tone arm drive device that horizontally rotates and raises and lowers a tone arm using the rotational force of a motor includes a motor, a pulley that rotates in accordance with the rotation of a drive shaft of the motor, and a bearing for the rotation shaft of the pulley. is fixed and has a first position and a second position.
a moving member supported so as to be movable between positions;
a holding member for holding the movable member in the first position; an elevating drive section having a cam section for elevating and lowering the tone arm; and a horizontal drive section for horizontally rotating the tone arm. and a transmission belt stretched between the pulley and the lifting drive unit for transmitting the rotation of the motor to the lifting drive unit, the holding member moving the moving member to the first position. 1. A tone arm drive device, characterized in that when displacement retention is released, the tension of the transmission belt is used to transmit the rotation of the motor to the horizontal drive section.