JPH0222834Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a disk clamp structure that is optimal for clamping the disk of a compact disk player to a turntable.

[Background technology] In a compact disk player, a clamper that is movable relative to the tip of the clamp arm by a predetermined amount is brought close to the turntable by the clamp arm's rotation movement in a vertical plane, and a magnet attached to the clamper is moved toward the turntable. The clamper fixes the disk to the turntable by adsorption.

However, with this conventional clamp structure,
The clamper needs to rotate with the turntable and disk when they rotate, and the clamper needs to be centered using a positioning mechanism installed between the turntable and the clamper. It is possible to move relative only. For this reason, when the clamp arm tilts and the clamper moves above the turntable when the disc is inserted or removed, the relative position of the diagonally tilted clamp arm and the clamper changes, and when the performance starts, the clamp arm lowers and the clamper presses the disc. In some cases, the clamper may not be centered properly. In addition, it is necessary to adjust the height of the clamp arm in order for the clamper to properly press the disc against the turntable at the start of a performance, and when the clamper is retracted above the turntable, the height of the tip of the clamp arm varies greatly. , which makes designing the player case difficult.

[Purpose of the invention] Taking the above-mentioned facts into consideration, the object of the present invention is to provide a disk clamp structure that allows the clamper to be centered easily and reliably and eliminates the need for adjusting the height of the clamper.

[Summary of the invention] In the disk clamp structure according to the invention, the clamper is suctioned and raised by a solenoid provided above the turntable, and upper positioning means having tapered surfaces in contact with each other is provided between the solenoid and the clamper. The damper is provided to center the clamper, and the clamper is designed to fall when the excitation force of the solenoid decreases, eliminating the need for height adjustment.

[Embodiment of the invention] Figs. 1 and 2 show a part of a compact disc player to which a disc clamp structure according to the present embodiment is applied. The main chassis 10 has a turntable 12 whose axis is perpendicular to the center thereof.
is pivoted. This turntable is rotated by a disk motor 14 attached to its lower part, and has a guide 1 protruding from its upper end surface.
6 is for insertion into the central circular hole of the disk 18.

A laser beam is irradiated onto the back surface (bottom surface) of this disk 18 by a reading device (not shown).
The presence or absence of minute pits formed on the back surface of the disk 18 is detected by the reflected light, and signals are thereby read out.

The upper end of the guide 16 has a tapered surface 16 on its outer periphery.
A, and is used for positioning when placing the disk 18 on the turntable 12.

On the main chassis 10 is a roughly gate-shaped sub chassis 20.
is fixed. A solenoid 22 is attached to the center of this sub-chassis 20, and a clamper 24
It is used for driving. This solenoid 22 is provided with a ring-shaped coil 26 whose axis is perpendicular, and is designed to generate an excitation force when energized from a control device (not shown).

The clamper 24 has a cylindrical movable iron core 30 protruding from the upper end of the axial center of the clamper body 28. This movable iron core 30 has a coil 26 as shown in FIG.
is attracted and raised into the coil 26 by the excitation force of
Its upper end corresponds to a guide 32 provided on the solenoid 22. That is, a guide tapered surface 30A is formed at the upper end of the movable iron core 30, and a corresponding guide tapered hole 32A is formed in the guide 32. Therefore, when the movable iron core 30 rises, the guide tapered surface 30A
comes into contact with the guide tapered hole 32A and the solenoid 2
2 and is coaxially attracted and held so that centering is performed. Therefore, the guide tapered surface 30A and the guide tapered hole 32A constitute upper positioning means.

A rubber cushion 34 is attached to the bottom of the guide tapered hole 32A to absorb the impact when the movable iron core 30 rises.

The clamper body 28 has a guide tapered surface 3 whose outer shape decreases toward the upper end near the fixed portion of the movable iron core 30.
6, and this guide tapered surface 36 comes into contact with the inner peripheral surface of the lower end of the cylindrical holder 38 of the solenoid 22, so that the centering of the movable iron core 30 by the above-mentioned upper positioning means can be performed more accurately.

A projection 40 projects vertically downward from the central lower end of the clamper main body 28, and a tapered hole 42 opening toward the turntable 12 is bored in the lower end surface of the projection 40. This tapered hole 42 corresponds to a tapered projection 46 that projects upward into a circular hole 44 at the upper end of the axis of the turntable 12 . The tapered hole 42 and the tapered protrusion 46 are designed so that when the clamper body 28 falls under its own weight as shown in FIG. 2, the clamper body 28 is placed coaxially on the turntable 12 and centered. There is.

A protrusion 4 protruding in the radial direction of the clamper body 28
8 corresponds to a cylindrical hook 50 attached to the lower end of the sub chassis 20. This cylindrical hook 50 has a flat plate hook 52 protruding in the axial direction on its lower end surface, and this flat plate hook 52
The outer shape of the protrusion 48 is larger than the inner side of the protrusion 48. Therefore, the clamper body 28 is connected to the solenoid 22.
Even when the excitation force is removed, consideration is given so that it is held by this cylindrical hook 50 and does not slip out from the cylindrical hook 50.

A magnet 54 is fixed to the clamper body 28, and when the clamper body 28 falls due to its own weight as shown in FIG. 2, the magnet 54 is attracted to the turntable 12. It has a structure in which the disk 18 is clamped and fixed between the turntable 12 and the turntable 12.

The solenoid 22 is energized to raise the clamper body 28 when the main switch of the compact disc player is turned on.
A circuit for controlling coil 26 is shown in FIG. In FIG. 3, switching element 5
6 is designed to obtain a large output signal from the output terminal 60 with a signal to the input terminal 58, and as shown in FIG. It is getting smaller in the state where it is.

Next, the operation of this embodiment will be explained.

When the main switch of the compact disc player is turned on, the coil 26 of the solenoid 22
When the coil 26 is energized, the clamper main body 28 is lifted and attracted by the excitation force. During this upward movement, the guide tapered surface 30A is aligned with the guide tapered hole 3.
By coming into contact with 2A, the clamper main body 28 is accurately centered.

When the disk 18 is placed on the turntable 12 and the turntable 12 is moved horizontally and coaxially placed directly below the solenoid 22, a control means (not shown) cuts off the power to the solenoid 22. . As a result, the excitation force is eliminated, and the clamper main body 28 falls onto the turntable 12 under its own weight.

Since the clamper main body 28 is already accurately centered in the raised position, it can accurately fall onto the turntable 12 even when lowered. Further, as shown in FIG. 2, when descending, the tapered hole 42 of the clamper body 28 comes into contact with the tapered protrusion 46, thereby achieving more accurate centering.

By attracting the magnet 54 to the turntable 12, the disk 18 is clamped and fixed between the clamper body 28 and the turntable 12.

Thereafter, the turntable 12 is rotated by energizing the disc motor 14, but the clamper body 2
8 is accurately centered on the turntable 12, the unbalanced load on the clamper body 28 is small even during high speed rotation.

When the reading of the signal from the disk 18 is completed, the solenoid 22 is energized again, and the clamper main body 28 is raised by the excitation force, and the disk 18 is taken out.

Next, FIG. 5 shows the main parts of a second embodiment of the present invention. In this embodiment, positioning means are formed between the upper end of the movable core 30 and the guide 32, and between the guide tapered surface 36 and the inner peripheral surface of the lower end of the holder 38, respectively, unlike the previous embodiment.

That is, the upper end of the movable iron core 30 is not formed with a tapered surface as in the previous embodiment, but has a cylindrical shape and is in almost linear contact with the inner peripheral surface of the guide taper hole 32A. Also, the guide tapered surface 36
is in contact with the inner circumferential surface of the lower end of the holder 38 in a substantially line contact state.

Therefore, the clamper 2 is
4 has its axis vertical.

Further, in the third embodiment of the present invention shown in FIG.
The clamper 24 is centered by making surface contact with the clamper 24.

In this embodiment, the solenoid 2 corresponds to the guide tapered surface 30A formed at the upper end of the movable core 30.
2, a guide tapered hole 32A is formed.
The guide tapered surface 30A and the guide tapered hole 32A are arranged with a slight distance from each other to prevent the movable core 30 from being largely displaced.

[Effect of the invention] As explained above, in the disk clamp structure according to the invention, the clamper is suctioned vertically upward by the solenoid provided above the turntable, and
Since centering is performed by the upper positioning means between the clamper and the solenoid, the clamper can be accurately centered, and has the excellent effect of eliminating the need for vertical adjustment of the clamper.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view showing an embodiment of the disk clamp structure according to the present invention, Fig. 2 is an operation diagram of Fig. 1, Fig. 3 is a partial circuit diagram showing a solenoid control circuit, and Fig. 4 is a control circuit. A diagram showing the relationship between elapsed time and passing current in the circuit, and FIGS. 5 and 6 are sectional views showing the second and third embodiments of the present invention, respectively. 12...turntable, 18...disc,
22... Solenoid, 24... Clamper, 26...
... Coil, 28 ... Clamper body, 30 ... Movable iron core, 32 ... Guide, 54 ... Magnet.

Claims (1)

[Scope of utility model registration request] A solenoid installed above the turntable, a clamper that is attracted to the solenoid and rises, and then falls as the excitation force of the solenoid decreases.
A magnet is attached to the clamper and fixes the disk to the turntable by the force of attraction to the turntable, and a tapered surface is provided between the clamper and the solenoid and touches each other, and the clamper is centered in the raised position of the clamper. A disk clamp structure comprising: an upper positioning means; and a lowering positioning means provided between the clamper and the guide, having tapered surfaces in contact with each other and centering the clamper at the lowered position of the clamp.