JPH042401Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a tone arm elevating device for elevating and lowering a tone arm.

Recently, record players have become smaller, and as a result, the tone arm elevating device also needs to be smaller. In addition, the dimensional accuracy of the push-up rod and boss that push up the tone arm must be on the order of μ, so they must be easy to attach and detach, and because the tone arm is lowered gently, the heavy bobbin must be lowered. When doing so, it is necessary that the bobbin be isolated from the push-up rod.

The present invention provides a tone arm lifting device that satisfies these requirements, and will be described below with reference to the drawings. 1 is a record player board; 2 is a tone arm attached to a shaft 3 rotatably attached to the record player board 1 with a pin 4 so that its tip can move up and down; 5 is a lifter; An annular magnet 7 provided in a case 6 fixed to the coil bobbin 8, a coil 9 wound around a bottomed cylindrical coil bobbin 8 and disposed within the magnet 7, and an iron center yoke that guides the coil bobbin 8. 10, and a support arm assembly 11 provided on the center yoke 10. Further, the support arm assembly 11 has a push-up bar 13 having a support arm 12 corresponding to the tone arm 2, a boss 14 for accurately regulating the position of the push-up bar 13 on the record player board 1, and a coil spring 15. , these are all made of non-magnetic material,
Further, the lower end of the push-up rod 13 is placed on the bottom surface of the coil bobbin 8.

The tone arm lifting device of the present invention has the above-described configuration. Now, in order to move the tone arm 2 to play a record, it is necessary to lift the tip of the tone arm 2. To do this, when a current is passed through the coil 9, the lines of magnetic force generated by the coil 9 are applied to the magnet 7 through the center yoke 10, so that the coil 10 and the magnet 7
A magnetic force acts between them to levitate the coil bobbin 8.
Along with this, the push-up rod 13 is also floated against the tension force of the coil spring 15, and the support arm 12
hits the tone arm 2 and pushes up the tip of the tone arm 2. The rear shaft 3 is a motor (not shown)
The tone arm 2 is rotated by the tone arm 2. When the tone arm 2 is moved above the introduction groove of the record board, the motor is stopped and the tone arm 2 is also stopped. The supply of current flowing through the coil 9 is also stopped. When the supply of current to the coil 9 is stopped, the coil 9 and the magnet 7
The magnetic force between them disappears, and the coil bobbin 8 quickly falls due to its own weight and the weight of the coil. However, the push-up rod 13 is only affected by the viscous resistance of the silicone oil in the oil sump groove 16.
The tone arm 2 is slowly lowered in balance with the weight of the support arm 12 and the pressing rod 13 and the tension of the coil spring 15, and the record stylus is fitted into the groove of the record plate. Since the support arm assembly 11 is made of a non-magnetic material, it is not magnetized and does not affect the vertical movement of the push-up rod 13.

When the support arm assembly 11 needs to be replaced due to looseness or the like occurring between the boss 14 and the push-up bar 13 during use, the support arm assembly can be replaced by loosening the boss 14 from the record player board 1 and pulling it out. The entire assembly 11 is removed. When inserting, the inner diameter of the hole in the center yoke 10 is guided by the outer diameter of the boss 14, so that the support arm assembly 11 can be mounted accurately without eccentricity.

As described above, the tone arm lifting device of the present invention has a push-up bar that pushes up the tone arm, and a coil and coil bobbin that push up the push-up bar, which are separately formed, so that when the tone arm is lowered, the weight of the coil, etc. is pushed up. Since it does not touch the rod, the tone arm can be lowered gently. Further, since the boss of the support arm assembly is guided by the center yoke and inserted into the center yoke, the support arm assembly can be accurately installed without eccentricity.

[Brief explanation of the drawing]

The figure is a sectional view of the tone arm lifting device of the present invention. 2...Tone arm, 5...Lifter, 7...
Magnet, 8... Coil bobbin, 9... Coil, 10... Center yoke, 11... Support arm assembly, 13... Push up bar, 14... Boss.

Claims (1)

[Scope of utility model registration request] An annular magnet, a bottomed cylindrical coil bobbin around which a coil is wound opposite to the magnet, a center yoke that guides the coil bobbin in a vertically movable manner, and an upper end that is loosely inserted into the center yoke. The coil bobbin is provided with a support arm, and a push-up bar whose lower end is placed on the bottom surface of the coil bobbin, and a support arm assembly including a buffer member provided between the push-up bar and the center yoke, and the coil is energized. The electromagnetic force generated between the magnet and the coil is guided by the center yoke together with the coil bobbin to levitate the push-up bar, push up the tone arm, and rapidly lower the coil bobbin by stopping the current supply to the coil. The tone arm lifting device is also characterized in that the push-up bar is lowered gently by a buffer member.