JPH0454568Y2 - - Google Patents

Description

[Detailed Description of the Invention] "Industrial Application Field" The present invention is for holding the reading device of a disc player, that is, the optical information reading device so as to always maintain an appropriate positional relationship with respect to the disc surface. This invention relates to a tilt mechanism, which is one of various tracking mechanisms.

``Prior Art'' Conventionally, optical information reading devices of disk players have always maintained an appropriate positional relationship with respect to the disk surface of a disk-type record carrier (hereinafter referred to as a disk) on which information to be played is recorded. There is a need to hold and move optical information reading devices in a consistent manner, and devices for adjusting the mounting position of optical information reading devices for this purpose have been developed in various fields.

In particular, non-contact type optical disc players are susceptible to vertical vibrations of the disc that occur when it rotates, track vibrations that occur in the radial direction due to eccentricity of the disc, and spiral vibrations formed on the disc. An important technical challenge is to control the objective lens to accurately follow the movement of the entire optical information reading device, such as sliding, to follow the signal track from the inner circumference to the outer circumference.

The optical information reader mounting position adjustment device is equipped with a tilt mechanism, slide mechanism, and angle adjustment mechanism.
The purpose of overcoming this technical issue is to provide a focus servo, tracking servo, tangential servo, slider servo, etc., and to ensure that the objective lens always follows accurately through its control circuit. .

Among these, the tilt mechanism has a mounting base attached so that the tilt member can freely rotate in the radial direction of the disk around a fulcrum.The tilt mechanism works by rotating the tilt member so that the optical information reading device is attached to the disk. This is for following the target while maintaining a predetermined distance and angle. The range in which this tilt mechanism can be adjusted is limited to a range preset at the time of design in relation to the disk surface. Various methods have been developed to properly drive this tilt mechanism within a predetermined range, but normally the operation is turned on and off by arranging drive system mechanisms such as motors and gears and limiters at the upper and lower limits. It involved a combination of electrical control system mechanisms such as:

``Problems to be solved by invention'' As mentioned above, in the past, when trying to electrically drive a tilt mechanism within a predetermined range using a limiter, an electric control device including a limiter was used. Expensive parts were needed. This causes an increased burden in terms of cost and space, and goes against the product development concept of realizing small, inexpensive, high-performance products.

Therefore, the present invention mechanically incorporates a device that controls the limits of tilt operation into the drive system mechanism, so that even if the electric control device including the limiter is removed, tilt operation is automatically performed at the upper and lower limits. It was designed to stop.

``Means to Solve the Problems'' The present invention, as a means to solve the above technical problems, includes a tilt member rotatably attached to the mounting base around a tilt fulcrum, and rotated in the radial direction of the disk. In a tilt mechanism that adjusts the distance and radial angle of an optical information reading device with respect to a disk surface, a drive unit that rotates a tilt member in the radial direction of the disk includes a transmission gear that rotates using a tilt motor as a drive source; a cam gear that meshes with the cam gear; a locking member that abuts the lifting cam portion of the cam gear;
It consists of a biasing body that generates a pullback force as the cam gear rotates in both left and right directions from a predetermined reference position, and the cam gear has a part of its tooth profile cut out to allow the gear change gear to mesh with it to idle. An idling portion is formed, and when the transmission gear rotates and the cam gear that engages is rotated against the biasing body, and the locking member that comes into contact reaches the upper or lower limit of the elevating cam portion, the transmission gear engages with the cam gear. This is a tilt adjustment mechanism for an optical information reading device, characterized in that the locking member is fitted into the idling portion of the holder and rotates idly to prevent the locking member from moving up and down any further.

"Operation" In order to operate the tilt adjustment mechanism of the present invention, the tilt motor is first driven. Then, the transmission gear rotates using this as a driving source, and the cam gear that meshes with it rotates against the pullback force of the biasing body. Then, when the locking member that comes into contact with the elevating cam part of the cam gear reaches the upper or lower limit of the elevating cam part, the gear change gear that has been meshed reaches the idle part of the cam gear and engages with it, where it idles. . As a result, the rotation of the cam gear is stopped, and the tilt operation is also stopped. Therefore, it is sufficient that the tilt motor is set to operate for predetermined times when the cam gear rotates clockwise and counterclockwise, respectively. This is because it is possible to mechanically stop the tilt operation with high accuracy at the upper and lower limits by idling. In addition, during this idling state, the biasing body exerts a pulling force to return to the direction in which it has been rotating, so it is very smooth to return from the idling state to the engaged state again.

``Example'' The present invention will be described in more detail below with reference to illustrated examples.

As shown in FIGS. 1 and 2, the mounting position adjustment device of the optical information reading device 9 includes a tilt mechanism 1,
It consists of a slide mechanism 2, a mounting angle adjustment mechanism 3, and a tilt fulcrum position adjustment mechanism 4.

In the tilt mechanism 1, a tilt member 7 is rotatably mounted on a mounting base 5 about a tilt fulcrum 6, and is rotated in the radial direction of a disk 8 to adjust the distance between the optical information reading device 9 and the disk surface 8a. This is a mechanism for adjusting the radial direction angle.

In the figure, receiving members 1 are planted on the left and right sides of the base 10.
A guide shaft 12 is horizontally suspended above the guide shafts 1 and 11', and a tilt member 7 is supported on the guide shaft 12 so as to be slidable and rotatable. The tilt member 7 also has a drive shaft (referred to as a screw shaft in the illustrated embodiment) that is rotated by a motor 13 for transporting the optical information reading device, which is a drive source.
14 is attached to the screw shaft 14, and a drive joint 15 that is movable left and right is screwed onto the screw shaft 14. The tilt member 7 thus constructed is configured to be rotatably mounted on the mounting base 5 erected on the base plate 10 about the tilt fulcrum 6 and rotated in the radial direction of the disk 8.

The drive unit for rotating the tilt member 7 in the radial direction of the disk is a worm gear 1 driven by a tilt motor 16 as a drive source, as shown in the figure.
6a, a transmission gear 17 that meshes with this, a cam gear 18 that meshes with this, a locking member 19 that comes into contact with the elevating cam portion 18a of the cam gear 18, and a rotation of the cam gear 18 in both left and right directions from a predetermined reference position. It is composed of a biasing body (spring) 18b that generates a pullback force in accordance with the movement.

As shown in FIG. 3, the cam gear 18 is equipped with a transmission gear 17 which has a part of its tooth profile cut out and meshes with the cam gear 18.
An idling portion 18c is formed in which the idling portion 18c is made to idly rotate.

Further, the elevating cam portion 18a is connected to the cam gear 1.
A cam portion 18a having an inclined surface is formed in a circular shape on the upper surface of the cam portion 8.

The biasing body (spring) 18b is the cam gear 18
One end is fixed to the base 10, and the other end is fixed to the cam gear 18. This biasing body (spring) 18b is
When the locking member 19 is in contact with the intermediate point of the cam portion 18a, it is in a neutral state, and is set to be reversed using this as a reference point, and a pullback force is generated both clockwise and counterclockwise. .

The transmission gear 17 includes a small gear 17a and a large gear 17b.
The small gear 17a meshes with the cam gear 18, and the large gear 17b meshes with the worm gear 16a.

The above-mentioned structural member rotates the cam gear 18 that meshes with the speed change gear 17 against the biasing body 18b, and the locking member 19 that comes into contact with the cam gear 18a engages with the cam gear 18a.
When you are guided by and reach the upper or lower limit,
The combination is configured such that the speed change gear 17 fits into the idle rotation portion of the cam gear 18 and idles, and the cam gear 18 does not rotate any further. In other words, even though the tilt motor 16 is still driving and the transmission gear 17 is rotating, it is spinning idly and the cam gear 18 has stopped rotating, so the locking member 19 cannot be raised or lowered further. do not.

Therefore, the tilt motor 16 simply operates clockwise and counterclockwise for a predetermined period of time, without having to start or stop the operation based on the signal detected by the conventional limiter. All you have to do is set it to do so. In other words, highly accurate stopping of operation at the upper and lower limits can be performed mechanically, separate from the driving force, making it possible to eliminate the electrical control device.
Moreover, in this state of idling, the biasing body (spring) 18b exerts a force to pull it back in the direction in which it has been rotating.
It is also smooth to return to the engaged state from the idling state.

``Effect of the invention'' As mentioned above, the invention has the following advantages in the tilt mechanism:
A drive unit that rotates the tilt member in the radial direction of the disk includes a speed change gear that rotates using a tilt motor as a drive source, a cam gear that meshes with the gear, and a locking member that comes into contact with the elevating cam part of the cam gear. ,
It consists of a biasing body that generates a pullback force as the cam gear rotates in both left and right directions from a predetermined reference position, and the cam gear has a part of its tooth profile cut out to allow the gear change gear to mesh with it to idle. An idling portion is formed, and when the transmission gear rotates and the cam gear that engages is rotated against the biasing body, and the locking member that comes into contact reaches the upper or lower limit of the elevating cam portion, the transmission gear engages with the cam gear. This prevents the locking member from moving up and down any further by fitting into the idling part of the locking member and idling.
It is possible to eliminate the electric control device including the limiter, which was conventionally required as a device for controlling the limit of tilt operation.

As a result, the cost of parts for the electrical control device and the installation space can be reduced, making it possible to realize a compact, inexpensive, and high-performance product.

[Brief explanation of the drawing]

1 is a front view showing an optical information reading device mounting position adjusting device including a tilt adjustment mechanism of an optical information reading device according to the present invention; FIG. 2 is a plan view of the optical information reading device mounting position adjusting device; and FIG. The figure is a perspective view showing the main parts of the tilt adjustment mechanism of the optical information reading device. Explanation of symbols of main components, 1...Tilt mechanism, 2...Slide mechanism, 3...Mounting angle adjustment mechanism, 4...Tilt fulcrum position adjustment mechanism, 5...Mounting base, 6...Tilt fulcrum, 7 ...Tilt member, 8
...Disc, 9...Optical information reading device, 12...
...Guide shaft, 15...Drive joint, 16...
Tilt motor, 17...speed gear, 18...cam gear, 18a...lifting cam section, 18b...biasing body (spring).

Claims (1)

[Scope of utility model registration request] In a tilt mechanism, a tilt member is rotatably attached to the mounting base around a tilt fulcrum and rotated in the radial direction of the disk to adjust the distance and radial angle of the optical information reading device to the disk surface. A transmission gear that rotates a drive unit that rotates the member in the radial direction of the disk using a tilt motor as a drive source, a cam gear that meshes with the transmission gear, and a locking member that comes into contact with the elevating cam part of the cam gear.
It consists of a biasing body that generates a pullback force as the cam gear rotates in both left and right directions from a predetermined reference position, and the cam gear has a part of its tooth profile cut out to allow the gear change gear to mesh with it to idle. An idling portion is formed, and when the transmission gear rotates and the cam gear that engages is rotated against the biasing body, and the locking member that comes into contact reaches the upper or lower limit of the elevating cam portion, the transmission gear engages with the cam gear. 1. A tilt adjustment mechanism for an optical information reading device, characterized in that the mechanism is adapted to rotate idly by fitting into an idling portion of the device.