JPH04205975A - Head feeding device - Google Patents

Abstract

PURPOSE:To make the stop position of a head accurate and to prevent biting by stopping the motion of a protrusion, which is provided on a gear that transmits the driving force of a motor to a feed screw, at the prescribed stop position by a stop plate attached to a pickup head. CONSTITUTION:This device is provided with the gears 12-15 that transmit the driving force of the motor 11 to the feed screw 16, the protrusion 13a that is provided not axially on the side of the gear 13, and the stop plate 19 that is attached to the pickup head 17 and stops the motion of the protrusion 13a at the prescribed stop position. And, by stopping by the stop plate 19 the motion of the protrusion 13a provided on the gear 13 that transmits the driving force of the motor 11 to the feed screw 16, the head feeding mechanism is also stopped. Thus, the stop position of the head 17 is accurate, and also the biting of the pickup head 17 when it does not stop because of inertia is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention (Field of Industrial Application) The present invention relates to a head feeding device for a CD player, a CD-ROM driver, a floppy disk drive, etc.

(Prior Art) In a CD player, signals are recorded from the inner circumference to the outer circumference of the CD. Then, before playback, move the pickup head to the T, O, C,
It is necessary to move to the table of contents of the disc signal called the (Table of'contents) area.

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FIG. 5 is a plan view of a conventional head feeding device, and FIG. 6 is a side view of this head feeding device.

As shown in the figure, the rotation of the electric motor 1 is caused by gears 2, 3, 4.
5 to the feed screw 6. One end of the pickup head 7 is slidably fitted onto the guide shaft 8. On the other hand, the other end of the pickup head 7 meshes with the feed screw 6 and is slidably driven by rotation of the feed screw 7.

In this way, the pickup head 7 moves in the A direction and the B direction as the electric motor 1 rotates.

Then, as shown in FIGS. 7 and 8, when the pickup head 7 moves to T, O, or C, press the pickup head 7 or the pickup head stop switch 9,
The signal from this stop switch 9 turns off the power to the electric motor 1, and the pin-qua 1. Puhe,.

It had stopped the door.

However, in such a conventional head feeding device, even after the electric motor 1 is de-energized by detecting the signal from the pickup head stop switch 9, the pickup head 7 does not stop immediately due to the inertia of the pickup head 7, and the pickup head stops. The switch 9 goes beyond the detection position of the signal. This inertia was not constant due to external conditions such as friction in the feed system and temperature, which caused the problem that the stopping position was not constant.

In addition, in the case of a feed screw mechanism, the pickup stop position is usually near the end of the feed screw 6, or if the pick amplifier head 7 does not stop at the end of the feed screw 6 due to inertia, the pickup stop position is usually near the end of the feed screw 6. The engaging portion of the pickup head 7 may become jammed.

(Problem to be Solved by the Invention) As described above, in the conventional head feeding device, even after the electric motor is turned off by detecting the signal from the pink-up head stop switch, the pickup head does not move due to the inertia of the pickup head. The pickup head does not stop immediately and goes beyond the detection position of the signal of the pickup head stop switch. This inertia was not constant due to external conditions such as friction in the feed system and temperature, and there was a problem that the stopping position was not constant.

In addition, in the case of a feed screw mechanism, the pickup stop position is usually near the end of the feed screw, but if the pickup head does not reach the end of the feed screw due to inertia and stops, the engaging part between the feed screw and the pickup head may engage. There was a problem with crowding.

The present invention was created to solve the above problems, and an object of the present invention is to provide a head feeding device that can accurately stop the head and prevent jamming.

[Structure of the Invention] (Means for Solving the Problem) In order to achieve the above object, the head feeding device of the present invention has a pickup head that holds a pickup and meshes with the pickup head, so that the pickup head can be moved. A feed screw for movement, a motor for driving the feed screw, a gear for transmitting the driving force of the motor to the feed screw, and a protrusion provided on a side surface of the gear and a stop plate provided on the pickup head to stop the movement of the protrusion at a predetermined stop position.

(Function) In the head feeding device of the present invention, the stop plate provided on the pickup head stops the movement of the protrusion provided on a different axis on the gear that transmits the driving force of the motor to the feed screw at a predetermined stop position. By stopping, the pickup head stops.

Therefore, the shift of the head stop position due to inertia and the resulting jamming are eliminated.

Further, the energization F of the motor may be stopped by detecting the stoppage of rotation of the motor using a back electromotive force generated in the motor, a current, a speed detection device, or the like.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a plan view showing the configuration of an embodiment in which the head feeding device of the present invention is applied to a CD player. 2 is a side view of the head feeding device shown in FIG. 1. FIG.

As shown in the figure, the rotation of the electric motor 11 is controlled by the gears 12 and 13.
．． 14 and 15 to the feed screw 16. One end of the pickup rod 17 is slidably fitted onto the guide shaft 18. On the other hand, the other end of the pickup head 17 meshes with the feed screw 16 and is slidably driven by the rotation of the feed screw 16.

Further, the gear 13 is provided with a protrusion 13a on a different axis.

In this way, the pickup head 17 is moved in the entry direction, the B direction, as the electric motor 11 rotates. Further, a stop plate 19 is provided on the feed screw 16 side of the Rad 17 to the pickup.

FIG. 3 is a plan view of the head feeding device in the stopped position, and FIG. 4 is a side view of the head feeding device in the stopped position.

As shown in these figures, T,0. When the pickup head 17 moves to C, the pickup head 1
A stop plate 19 provided on the gear 13 stops the movement of the protrusion 13a provided on the gear 13. For this purpose, the drive system consisting of gears and an electric motor is stopped. Further, at the same time as the drive system is stopped, a counter electromotive force is generated in the electric motor 11. This back electromotive force is detected by a detector (not shown) and the energization of the electric motor 11 is stopped. Further, the energization of the electric motor 11 may be stopped by current detection or speed detection.

Therefore, according to the head feeding device of this embodiment, the stop position of the head can be made accurate and jamming can be prevented.

[Effects of the Invention 1] As explained above, according to the head feeder of the present invention, the stop plate provided on the pickup head or the side surface of the gear for transmitting the driving force of the motor to the feed dog has a different axis. Since the head feeding mechanism is stopped by stopping the movement of the protrusion provided on the head, the stop position of the head becomes accurate and jamming can be prevented.

[Brief explanation of the drawing]

FIG. 1 is a plan view of the head feeding device of this embodiment, FIG. 2 is a side view of the head feeding device shown in FIG. 1, and FIG. 3 is a plan view of the head feeding device of this embodiment at the head stop position.
4 is a side view of the head feeding device of this embodiment at the head stop position, FIG. 5 is a plan view of a conventional head feeding device, FIG. 6 is a side view of the head feeding device shown in FIG. 5, and FIG.
The figure is a plan view of the conventional head feeding device shown in FIG. 5 at the head stop position, and FIG. 8 is a side view of the conventional head feeding device shown in FIG. 5 at the head stopping position. 11・Electric motor, 12,] 3.14.15・Gear, 13a
... Protrusion, 16... Feed screw, 17... Pink up head, 18... Guide shaft, 19... Stop plate. Applicant Toshiba Corporation Representative Patent Attorney Sasa Suyama −

Claims (1)

[Claims] (1) A pickup head that holds the pickup; a feed screw that meshes with the pickup head and moves the pickup head; a motor that drives the feed screw; A gear that transmits transmission to a screw, a protrusion provided on a side surface of the gear in an off-axis manner, and a stop plate provided on the pickup head to stop the movement of the protrusion at a predetermined stop position. A head feeding device characterized by: