JP2005004914A - Transmission path changeover mechanism of disk drive device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To smoothly change over the transmission of power to a feed roller and a lead screw by preventing gears from being engaged with each other uncertainly. <P>SOLUTION: There are provided two gear trains 11, 12. They share a drive source 10, a main gear 6 rotated forwardly and backwardly with the drive source, and a partly toothless gear 7 and a planet gear 8 engaging with the main gear. The gear train 11 includes a transmission gear 11A for transmitting the drive force of the planet gear 8 to the feed roller 1, and the gear train 12 includes a transmission gear 12A for transmitting the drive force of the planet gear 8 to the lead screw 3. The planet gear 8 is coupled with the main gear 6 with the aid of a turning arm 9 to alternately engage with the transmission gears 11A, 12A, and a cam groove 7C is formed on the partly toothless gear 7 for controlling a turning speed of the planet gear by forcing a rotation shaft 8A of the planet gear 8 to engage therewith for secure engagement between the planet gear 8 and the transmission gears 11A, 12A. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disk drive device such as a CD player, and in particular, a transmission path of a disk drive device capable of rotationally driving a feed roller for transferring a disk and a lead screw for moving an optical pickup using a single motor. The present invention relates to a switching mechanism.
[0002]
[Prior art]
Disc drive devices such as CD players and DVD receivers that record / reproduce disc-shaped information recording media (discs) include various electronic components such as optical pickups that read disc recording information. In general, a disk can be automatically pulled or ejected by a roller. Here, there is an example in which the feed roller for transferring the disk and the lead screw for moving the optical pickup are rotated by separate motors, but this leads to an increase in size and cost of the apparatus.
[0003]
For this reason, in recent years, the same motor is used for rotationally driving the feed roller and the lead screw, and the power is alternately transmitted to the gear connected to the feed roller and the gear connected to the lead screw via a planetary gear (swing gear). I am doing so. However, in such a device, the rotation speed of the planetary gear depends on its rotational load, so the rotation speed of the planetary gear changes each time due to external factors such as wear of members and temperature, and this causes the modulation of timing. The tip of the planetary gear and the gear on the other side may collide and the two may not mesh. In this case, there may be a problem that a loud impact sound is generated or the motor stops due to overload.
[0004]
Therefore, there has been proposed a power transmission device that can prevent the occurrence of the above-described problems even when the gears are not properly meshed with each other (for example, Patent Document 1).
[0005]
The outline thereof will be described with reference to FIG. 8. M is a motor, a gear G1 is attached to its output shaft, a gear G2 is engaged with the gear G1, and G3 is engaged with the gear G2. The gears G2 and G3 are connected by an arm A1 having the center of the gear G2 as a turning fulcrum, and the gear G3 turns around the gear G2 between the gears G4 and G5 by forward and reverse rotation of the gear G2. The gear G4 is meshed with the gear G6, the gear G5 is meshed with the gear G7, and the gears G5 and G7 are connected by an arm A2 having the center of the gear G5 as a turning fulcrum, and the other end of the arm A2 is The operating point P is positioned in a cam groove formed in the gear G6.
[0006]
According to the conventional apparatus as described above, the gear G3 meshes with one of the gears G4 and G5 by forward and reverse rotation of the motor M, and the output shaft of the motor M is rotated counterclockwise in FIG. In this case, the gears G3 and G5 are engaged with each other, and then the gear G7 is turned so as to be engaged with the target gear G8.
[0007]
[Patent Document 1]
Japanese Patent Laid-Open No. 11-241756
[Problems to be solved by the invention]
However, in the conventional apparatus as described above, the turning speed of the gears G3 and G7 changes each time depending on the rotational load, so that the gears G3 and G5, the gears G3 and G6, and the gears G7 and G8 are meshed well. Not necessarily. For this reason, in Patent Document 1, the operating point of the arm A2 (power transmission path switching arm) is such that no impact noise or the like is generated even when the tooth tips of the gears G7 and G8 (power transmission path switching gear and the counterpart gear) collide. P is set in a free state so that the gear G7 (power transmission path switching gear) can escape. That is, the gear G6 (switching cam) fixes the operating point P so that the gear G7 is released when the tooth tips of the gears G7 and G8 collide, and the gears G7 and G8 are not engaged when the power transmission is interrupted. is there.
[0009]
Therefore, in Patent Document 1, even though the generation of noise due to the collision between the tooth tips of the gears G7 and G8 can be prevented, the collision between the tooth tips itself cannot be prevented. It is impossible to solve the problem that the operation of the entire transmission system is delayed by the time until the completion of.
[0010]
The present invention has been made in view of the circumstances as described above, and its purpose is to prevent uncertain meshing between gears and to transmit power to a feed roller for transferring a disk and a lead screw for moving an optical pickup. The purpose of this is to ensure that the switching is performed smoothly.
[0011]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides a disk having a feed roller 1 for transporting the disk and a lead screw 3 for moving the optical pickup 2 along the radial direction of the disk drawn by the feed roller. The drive device includes a first gear train 11 that rotationally drives the feed roller 1 and a second gear train 12 that rotationally drives the lead screw 3, and the gear trains 11 and 12 are the same drive source 10, and The main gear 6 rotated in the forward and reverse directions by the driving source, the toothless gear 7 and the planetary gear 8 meshing with the main gear are shared, and the first gear train 11 supplies the rotational driving force of the planetary gear 8 to the feed roller. The second transmission gear 1 has a first transmission gear 11 </ b> A that transmits the rotational driving force of the planetary gear 8 to the lead screw 3. A, and the planetary gear 8 is connected to the main gear 6 by the swivel arm 9 so as to alternately mesh with the first transmission gear 11A and the second transmission gear 12A, and between the first transmission gear 11A and the second transmission gear 12A. Is provided so as to be able to turn around the main gear 6, and the toothless gear 7 is provided with a planetary gear 8 in order to reliably engage the planetary gear 8 with the first transmission gear 11A and the second transmission gear 12A. A cam groove 7C for controlling the turning speed of the planetary gear is formed by engaging the rotation shaft 8A. After the planetary gear 8 is engaged with the first transmission gear 11A and the second transmission gear 12A, the intermittent gear 7 Provided is a transmission path switching mechanism of a disk drive device, wherein the planetary gear 8 is rotated by the drive source 10 while the gear portion 7A is disengaged from the main gear 6 and the toothless gear 7 is stationary. It is intended.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, application examples of the present invention will be described in detail with reference to the drawings. FIG. 1 is an enlarged view of a main part showing a bottom part of the disk drive device. In FIG. 1, reference numeral 1 denotes a feed roller for transferring a disk, 2 denotes an optical pickup disposed on the back side of the apparatus with respect to the feed roller, and 3 denotes a lead screw for supporting one side of the optical pickup. Is engaged with a rack (not shown) fixed to the optical pickup 2. By rotating the lead screw 3, the optical pickup 2 reads the recorded information on the disc while moving in the radial direction of the disc drawn by the feed roller 1 along the lead screw 3.
[0013]
10 is a common drive source (reversible motor) for rotationally driving the feed roller and the lead screw, 11 is a first gear train for transmitting the power of the drive source to rotationally drive the feed roller, and 12 is for rotationally driving the lead screw. It is the 2nd gear train which performs motive power transmission of a drive source.
[0014]
In this example, the gear train 11 includes a worm 4 fixed to the output shaft of the drive source, an idle gear 5 that meshes with the worm, a main gear 6 that meshes with the idle gear, a toothless gear 7 that meshes with the main gear, a planetary gear 8, and the like. A first transmission gear 11A meshed with the planetary gear, a gear 11B meshed with the transmission gear, a gear 11C meshed with the gear, a gear 11D meshed with the gear, a gear 11E meshed with the gear, a gear 11F meshed with the gear, The gear 11G meshes with the gear and the gear 11H meshes with the gear.
[0015]
In such a gear train 11, except for the planetary gear 8 and the gears 11D and 11H, except for the planetary gear 8 and the gears 11D and 11H, only the rotational movement is performed at a fixed position. It is configured to perform a rotational motion and a turning motion.
[0016]
Among them, the planetary gear 8 is connected to the main gear 6 by a turning arm 9 (carrier) whose center (spinning axis 8A) is a turning fulcrum with the center of the main gear 6 as a turning fulcrum. 8 rotates (revolves) while turning (revolving) around the main gear 6. Further, when the drawing of the disk by the feed roller 1 is completed, the gear 11D turns in a direction away from the gear 11E while being engaged with the gear 11C by a mechanism (not shown). Further, the final gear 11H is fixed to one end of the feed roller 1, and moves together with the feed roller 1 in a direction away from the recording surface of the disc when the drawing of the disc is completed.
[0017]
On the other hand, the gear train 12 includes the worm 4, the idle gear 5, the main gear 6, the toothless gear 7, the planetary gear 8, and the second transmission gear 12A that rotates at a fixed position when the planetary gear 8 is meshed. And a worm 12B fixed to one end of the lead screw 3 and meshing with the transmission gear 12A.
[0018]
As described above, the two gear trains 11 and 12 share the drive source 10, the worm 4, the idle gear 5, the main gear 6, the toothless gear 7, and the planetary gear 8. The force is alternately switched and transmitted to the transmission gears 11A and 12A. That is, when the main gear 6 is rotated counterclockwise in FIG. 1 through the idle gear 5 by driving the drive source 10, the planetary gear 8 meshing with the main gear 6 rotates counterclockwise while rotating in the opposite direction. The gears 11A to 11H are meshed with the transmission gear 11A, whereby the gears 11A to 11H are rotated in the directions indicated by the arrows, and the feed roller 1 is rotated in the direction of ejecting the disk. When the planetary gear 8 is engaged with the transmission gear 11 </ b> A and the drive source 10 is driven in the opposite direction, the gears 11 </ b> A to 11 </ b> H are also connected via the worm 4, the idle gear 5, the main gear 6, and the planetary gear 8. And the feed roller 1 is rotated in the direction of drawing the disk.
[0019]
On the other hand, when the main gear 6 is rotated in the clockwise direction in FIG. 1 through the idle gear 5 by driving the drive source 10, the planetary gear 8 meshing with the main gear 6 rotates in the clockwise direction while rotating in the opposite direction to the transmission gear. 12A, thereby rotating the lead screw 3 via the transmission gear 12A and the worm 12B, and the optical pickup 2 having a rack meshing with the outer periphery of the disk whose center is clamped on a turntable (not shown) To move in the direction. Further, when the drive source 10 is driven in the opposite direction to the above while the planetary gear 8 is engaged with the transmission gear 12A, the transmission gear 12A and the worm 12B are transmitted via the worm 4, the idle gear 5, the main gear 6, and the planetary gear 8. The lead screw 3 also rotates in the opposite direction to the above, so that the optical pickup 2 moves toward the center of the disk.
[0020]
In the state where the planetary gear 8 is engaged with the transmission gears 11A and 12A, the rotation of the planetary gear 8 is suppressed by the toothless gear 7, and for this reason, the planetary gear 8 is engaged with the transmission gears 11A and 12A. In this state, the rotational driving force of the planetary gear 8 can be transmitted to the transmission gears 11A and 12A to rotate the feed roller 1 and the lead screw 3 in the forward and reverse directions. In particular, when the planetary gear 8 is engaged with the transmission gears 11A, 12A by the turning operation of the planetary gear 8, the rotational speed of the planetary gear 8 is ensured by the missing gear 7 so that the engagement between the two is ensured without causing the tooth tips to collide with each other. The rotation speed is controlled.
[0021]
FIG. 2 shows such a missing gear. As is apparent from this figure, a gear portion 7A is formed on the outer periphery of the toothless gear 7, and about 1/4 of the outer periphery is a toothless portion 7B having no gear portion. Further, as shown in FIG. 2A, a substantially C-shaped cam groove 7C is formed on the bottom surface of the toothless gear 7 so as to surround the center portion thereof. On the other hand, as shown in FIG. 2 (B), an annular cam contour portion 70 having three step portions 71, 72, 73 projects from the center portion of the upper surface of the toothless gear 7, and 2 near the outer periphery. Two convex portions 74 and 75 are formed.
[0022]
The segmented gear 7 as described above is disposed at a position where the gear portion 7A meshes with the main gear 6 shown in FIG. 1, and the planetary gear 8 is disposed on the bottom surface so as to overlap the planetary gear 8. The center rotation shaft 8A of the gear engages with the cam groove 7C. As a result, when the main gear 6 rotates, the toothless gear 7 and the planetary gear 8 rotate in the opposite direction to the main gear 6, and the planetary gear 8 is guided in its main shaft while being guided by the cam groove 7C of the toothless gear. It turns around the gear 6. Therefore, the planetary gear 8 can reliably engage with the transmission gears 11A and 12A by performing a determined turning motion while controlling not only the turning speed but also the rotation speed by the cam groove 7C.
[0023]
Thus, as shown in FIGS. 3 to 4, when the meshing of the planetary gear 8 and the transmission gears 11A, 12A is completed, the gear portion 7A of the missing gear is disengaged from the main gear 6 immediately thereafter (the missing tooth portion 7B is the main gear). This causes the toothless gear 7 to be stationary, and the planetary gear 8 is rotated by the drive source via the main gear 6 in this state, and the transmission gears 11A and 12A meshed with the planetary gear 8 are rotated. Power transmission is performed. At this time, the planetary gear 8 is prevented from rotating as described above with its rotation shaft 8A fitted in the cam groove 7C of the toothless gear, but after the meshing between the planetary gear 8 and the transmission gears 11A, 12A, the planetary gear 8 is missing. The tooth gear 7 is also prevented from rotating by a locking means described later so that the gear portion 7A does not mesh with the main gear 6.
[0024]
FIG. 5 shows a hook that constitutes the locking means. As shown in FIG. 5, the hooking claw 13 has a hub 14 that forms a hole in the center, and two arm portions 15 and 16 extending from the hub. One arm portion 15 has a bifurcated notch 15A and a spring described later. A hook 15B is formed to hold one end of the hook 15B.
[0025]
And the hook nail | claw 13 which concerns is attached so that it can rotate freely to the spindle 17 stood in the vicinity of the missing-tooth gear 7 as shown in FIGS. Further, the above-described spring 18 (torsion coil spring) is attached to the support shaft 17, and one end thereof is locked to the hook 15 </ b> B of the hook claw, and the other end of the spring 18 is on the upper surface of the toothless gear 7. And is in pressure contact with the cam contour portion 70.
[0026]
Here, FIG. 6 shows a state in which the planetary gear 8 and the transmission gear 11A are engaged with each other. At this time, the tip of the arm portion 16 of the hooking claw is pressed against the step portion 71 of the cam contour portion by the action of the spring 18, and the spring One end of 18 is pressure-bonded onto the step 72 of the cam contour portion, and urged in a direction to cause the step 71 to bite into the tip of the arm portion 16. Thereby, the toothless gear 7 is prevented from rotating, and the gear portion 7 </ b> A is kept in a state of not meshing with the main gear 6.
[0027]
On the other hand, FIG. 7 shows a state in which the planetary gear 8 and the transmission gear 12A are engaged with each other. At this time, the tip of the arm portion 16 of the hooking claw is pressed against the step portion 72 of the cam contour portion by the action of the spring 18. One end of the step is pressure-bonded onto the stepped portion 73 and urged in a direction to cause the stepped portion 72 to bite into the tip of the arm portion 16. Thereby, the toothless gear 7 is prevented from rotating, and the gear portion 7 </ b> A is kept in a state of not meshing with the main gear 6.
[0028]
Further, as shown in FIG. 7, when the planetary gear 8 and the transmission gear 12A are engaged with each other, the notch 15A formed on the arm portion of the hook is engaged with the small-diameter gear portion of the transmission gear 11A to lock the transmission gear 11A. ing. That is, since the transmission gear 12A is engaged with the worm 12B as described above, the planetary gear 8 does not rattle even when separated, but in this example, the transmission gear 11A and the gears 11B and 11C connected thereto are spur gears. Therefore, when the planetary gear 8 is separated from the transmission gear 11A, the transmission gear 11A receives an external force and rattles, thereby shifting the position of the tooth tip of the transmission gear 11A and causing the planet by the cam groove 7C as described above. There is a possibility that good meshing of the gear 8 is impaired. For this reason, in this example, using the hooking claw 13 that locks the toothless gear 7, the rotation of the transmission gear 11A is restricted until just before the planetary gear 8 is engaged with the transmission gear 11A, and the planetary gear 8 by the cam groove 7C. And the positive meshing of the transmission gear 11A is complemented.
[0029]
In FIG. 6, reference numeral 19 denotes a lever that operates when the disk is completely retracted by the feed roller. The lever 19 moves the convex portion 74 of the toothless gear 7 in conjunction with the movement of the feed roller away from the disk. It pushes in and acts to rotate the missing gear 7 counterclockwise in FIG. 6 against the elasticity of the spring 18. The gear portion 7A of the toothless gear meshes with the main gear 6 by the pressing action of the convex portion 74 by the lever 19, and the turning of the planetary gear 8 to the transmission gear 12A side is started.
[0030]
In FIG. 7, reference numeral 20 denotes a lever operated by an optical pickup. The lever 20 is pushed at one end by the optical pickup by moving the optical pickup 2 to an initial position on the center side of the disk. As a result, the tip of the lever 20 pushes the convex portion 75 of the toothless gear so that the toothless gear 7 is rotated in the clockwise direction in FIG. 7 against the elasticity of the spring 18. At this time, the gear portion 7A of the missing gear meshes with the main gear 6, and the turning of the planetary gear 8 toward the transmission gear 11A starts while the missing gear 7 is rotated in the clockwise direction in FIG. Is done.
[0031]
Although a preferred example of the present invention has been described above, the disk drive device is not limited to a CD player or a DVD receiver, and can be applied to various disk drive devices including a feed roller and an optical pickup.
[0032]
【The invention's effect】
As is apparent from the above description, according to the present invention, the turning speed of the planetary gear is controlled by the cam groove so that the planetary gear is engaged with the first transmission gear and the second transmission gear with certainty. Therefore, noise due to collision between tooth tips, stop of the drive source due to overload, transmission delay of power, and the like do not occur, and the reliability and quality of the apparatus can be greatly improved.
[0033]
Further, since the rotation shaft of the planetary gear is engaged with the cam groove, the planetary gear can be overlapped with the toothless gear forming the cam groove to reduce the arrangement space for both, thereby reducing the size and cost of the apparatus. .
[Brief description of the drawings]
FIG. 1 is an enlarged view of a main part of a disk drive device according to the present invention. FIG. 2 is a bottom view and a top view of a missing gear. FIG. 3 is an explanatory view showing a meshing state of a planetary gear and a first transmission gear. FIG. 5 is an enlarged view showing a hooking claw for locking the missing gear. FIG. 6 is a missing tooth when the planetary gear and the first transmission gear are engaged. FIG. 7 is an explanatory view showing a fixed state of a gear with no teeth when the planetary gear and the second transmission gear are engaged. FIG. 8 is a schematic view showing a conventional example.
DESCRIPTION OF SYMBOLS 1 Feed roller 2 Optical pick-up 3 Lead screw 6 Main gear 7 Partial gear 7A Gear part 7B Partial tooth part 7C Cam groove 8 Planetary gear 8A Rotating shaft 9 Turning arm 10 Drive source 11 1st gear train 11A 1st transmission gear 12 1st 2 gear train 12A 2nd transmission gear

Claims (1)

In a disk drive device comprising a feed roller for transporting a disk and a lead screw for moving the optical pickup along the radial direction of the disk drawn by the feed roller,
A first gear train for rotationally driving the feed roller; and a second gear train for rotationally driving the lead screw. The gear train is the same drive source, and the main gear is rotated forward and backward by the drive source. The first gear train has a first transmission gear that transmits the rotational driving force of the planetary gear to the feed roller, and the second gear train is A second transmission gear that transmits the rotational driving force of the planetary gear to the lead screw, and the planetary gear is coupled to the main gear by a swivel arm so as to alternately mesh with the first transmission gear and the second transmission gear; Between the gear and the second transmission gear, it is provided so as to be able to turn around the main gear, and the planetary gear is connected to the planetary gear for the positive engagement between the planetary gear, the first transmission gear and the second transmission gear. A cam groove for controlling the turning speed of the planetary gear is formed by engaging the rotation shaft of the planetary gear, and after the planetary gear is engaged with the first transmission gear and the second transmission gear, the gear portion of the toothless gear is the main part. A transmission path switching mechanism of a disk drive device, characterized in that a planetary gear is rotated by the drive source in a state where the gear is disengaged and is stationary.

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