JP2008146779A - Double gear - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a double gear capable of reducing noise generated during engagement without adding any component for absorbing backlash, preferably a double gear for an optical disk device. <P>SOLUTION: The double gear WG stacks together upper and lower gears 12 and 11 to engage engaging pieces 11g formed in at least two parts of one gear 11 with engaged pieces 12e formed in the other gear 12, and pressing the upper and lower gears to shift teeth 12f and 11h of the upper and lower gears from each other in a peripheral direction. In this case, one of the engaging piece 11g and the engaged piece 12e is formed into a spring piece to elastically engage the engaging piece 11g with the engaged piece 12e. The upper and lower gears 12 and 11 are pressed to be always brought into contact with each other, thereby preventing backlash. Thus, the upper and lower gears 12 and 11 are stably engaged with the other gear without being separated from/brought close to each other, and noise generated during engagement is greatly reduced. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a double gear incorporated in an optical disk device or the like, and more particularly to an improved double gear that can reduce noise generated when meshing.

  In the optical disk apparatus, a driving force transmission gear mechanism that transmits the driving force of the driving motor to the rack of the optical pickup, the rack of the cam slider, the rack of the tray, etc. is mounted. The first gear of this driving force transmission gear mechanism, That is, a double gear that removes so-called backlash may be incorporated as a gear that transmits the driving force of the driving motor to the rack gear of the optical pickup and the second and subsequent gears of the driving force transmission gear mechanism.

  As a double gear, upper and lower gears are overlapped, and an engagement piece formed at at least two locations of one gear and an engaged piece formed at a location corresponding to the engagement piece of the other gear, Known is one in which the upper and lower gears are engaged with each other in the vertical direction so that the upper and lower gears are not separated, and the upper and lower gears are biased by a spring so that the teeth of the upper and lower gears are displaced in the circumferential direction.

Also, in the optical disk apparatus, two pinions that are meshed in common with a rack of a sled moving mechanism equipped with an optical pickup are provided, and a backlash cancellation function that meshes with the pinions on the input side of the two stacked pinions There is also known a technique in which a backlash of the gear due to backlash is removed by providing an attached double gear (Patent Document 1).
JP 2003-306345 A

  However, in the conventional double gear described above, the engagement piece formed on one gear and the engagement piece formed on the other gear are engaged in the vertical direction so that the upper and lower gears are not separated. However, since the engagement piece and the engagement piece have backlash in the vertical direction, when engaging with other gears, the upper and lower gears move up and down in the vertical direction, which causes a loud noise (noise). ) Occurred.

  Such meshing noise (noise) can be reduced by attaching a nonwoven fabric between the upper and lower gears to absorb the backlash in the vertical direction. However, in that case, the number of parts and the number of assembling steps are increased by the amount of non-woven fabric and the like, and the cost becomes high.

  In addition, the optical disk apparatus of Patent Document 1 can remove backlash by the double gear, but since no countermeasure is taken to absorb the backlash in the vertical direction of the double gear, the sound (noise) generated at the time of meshing is reduced. I can't do it.

  The present invention has been made under the above circumstances, and the problem to be solved is that noise (noise) generated during meshing can be reduced without adding parts that absorb backlash such as nonwoven fabric. The object is to provide a double gear, preferably a double gear for an optical disc device.

  In order to solve the above-mentioned problem, the double gear according to the present invention corresponds to the engagement piece formed in at least two places of one gear by overlapping the upper and lower gears and the engagement piece of the other gear. In a double gear in which the upper and lower gears are urged so that the upper and lower gear teeth are displaced in the circumferential direction and the engaged pieces formed at the locations are engaged in the vertical direction so that the upper and lower gears are not separated. One of the engagement piece and the engagement piece is formed as a spring piece, and the engagement piece and the engagement piece are elastically engaged with each other.

  In the double gear of the present invention, one of the engagement piece or the engagement piece formed on the spring piece includes an inclined tip portion that elastically contacts the other engagement piece or the engagement piece, Or it is preferable to provide the protrusion part which elastically contacts the other to-be-engaged piece or engagement piece.

  A more specific preferable double gear for an optical disc apparatus according to the present invention includes an engagement piece formed by overlapping upper and lower gears in at least two places of one gear, and the engagement piece of the other gear. The upper and lower gears are engaged with each other so that the upper and lower gears are not separated from each other and the upper and lower gear teeth are biased in the circumferential direction. In the heavy gear, a small gear for moving the optical pickup and a small gear for driving other gears are formed on the upper surface and lower surface of the central portion of the lower gear, respectively, and a circular opening is formed in the central portion of the upper gear. Then, a small gear for moving the optical pickup is inserted into the circular opening, and one of the engagement piece and the engagement piece is formed as a spring piece, and the engagement piece and the engagement piece are It is characterized by being elastically engaged.

  As in the double gear of the present invention, either the engagement piece formed on one gear or the engagement piece formed on the other gear is formed on the spring piece, and the engagement piece and the engagement piece When the upper and lower gears are elastically engaged in the vertical direction, the upper and lower gears are urged so that they always come into contact with each other, and there is no backlash in the vertical direction, so that the upper and lower gears move up and down as in the past. Without being performed, the gears stably mesh with other gears, and the noise (noise) generated during meshing is greatly reduced. Accordingly, it is not necessary to attach a non-woven fabric or the like for absorbing backlash in the vertical direction between the upper and lower gears, so that the number of parts and assembly man-hours are not increased, and an increase in manufacturing cost can be suppressed.

  In particular, when one of the engagement piece or the engagement piece formed on the spring piece includes an inclined tip portion or a protrusion that elastically contacts the other engagement piece or the engagement piece, The protrusion can be pressed and elastically engaged with the other engaged piece or the engaging piece in a concentrated manner, and when the backlash is removed by the relative rotation of the upper and lower gears. Since there is almost no increase in frictional resistance, there is no concern about adverse effects on the backlash removal function.

  A more specific preferred double gear for an optical disk apparatus according to the present invention is incorporated as the first gear of the driving force transmission gear mechanism of the optical disk apparatus, and the upper and lower gears of the double gear serve as the output gear of the drive motor. The small gear for moving the optical pickup meshes with the rack gear of the optical pickup, and the small gear for driving other gears meshes with the second gear of the driving force transmission gear mechanism, so that the driving force of the driving motor is the second with the optical pickup. It is transmitted to the subsequent gears. At this time, the backlash with the output gear of the drive motor is removed by the double gear, and the noise (noise) generated during meshing as described above is also greatly reduced.

  Hereinafter, specific embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a plan view showing an example of an optical disc apparatus incorporating the double gear of the present invention, FIG. 2 is a perspective plan view of the optical disc apparatus seen through a tray, and FIG. 3 is a plan view according to one embodiment of the present invention. 4 is an exploded perspective view of the double gear, FIG. 5 is an enlarged partial sectional view taken along line AA of FIG. 3, and FIG. 6 is a double gear according to another embodiment of the present invention. It is an expanded partial sectional view of a gear.

  The optical disk apparatus illustrated in FIGS. 1 and 2 includes a main chassis 1, a traverse chassis 2, a tray 3, a turntable 4, an optical pickup 5, a clamper 6, a cam slider 7, a driving force transmission gear mechanism 8, a spindle motor M1, and a drive. The double gear WG of the present invention is incorporated as the first gear of the driving force transmission gear mechanism 8 and is composed of main components such as the motor M2.

  Briefly describing this optical disk apparatus, a traverse chassis 2 is disposed inside the main chassis 1 and is attached to the rear end thereof so as to be able to swing up and down. A turntable 4 and an optical pickup 5 are mounted on the traverse chassis 2, and the turntable 4 is rotated by a spindle motor M1. The optical pickup 5 is mounted along the main shaft 9a and the sub shaft 9b so as to be able to approach and separate from the turntable 4. A cam slider 7 is slidably attached to the front edge of the main chassis 1, and a boss 2 a protruding from the front end of the traverse chassis 2 is inserted into and engaged with the cam groove of the cam slider 7. ing. A clamper holding portion 1b is formed on the bridge portion 1a of the main chassis 1 so as to be positioned directly above the turntable 4. A clamper 6 is rotatably held by the clamper holding portion 1b. In addition, a tray 3 on which a disk is placed is attached inside the main chassis 1 so as to be freely inserted and removed through between the turntable 4 and the bridge portion 1a. A driving force transmission gear mechanism 8 for transmitting the driving force from the driving motor M2 to the optical pickup 5, the cam slider 7, and the tray 3 is provided.

  This driving force transmission gear mechanism 8 is a combination of a first gear, a second gear 8b, a third gear 8c, and a fourth gear 8d using the double gear WG of the present invention. Is engaged with the output gear 10 of the drive motor M2, and the small gear 11a for moving the optical pickup of the double gear WG is engaged with the rack gear 5a of the optical pickup 5. The fourth gear 8d meshes with the rack gear 7a of the cam slider 7 and the rack gear 3a on the back surface of the tray 3. The fourth gear 8d has a toothless portion. When the traverse chassis 2 is raised and the optical disk is chucked by the turntable 4 and the clamper 6, the third gear 8c is the fourth gear. It is located in the part without 8d teeth so as not to mesh.

  The operation of this optical disk apparatus will be briefly described. When the optical disk is rotated by being chucked by the turntable 4 and the clamper 6, the optical pickup 5 is moved toward the turntable 4 by the small gear 11a of the double gear WG. However, recording / reproduction is performed by irradiating the optical disk with the laser beam from the objective lens 5b. At this time, the third gear 8c and the fourth gear 8d of the driving force transmission gear mechanism 8 are not engaged with each other. When the optical disk is taken out after recording / reproduction is completed, the optical pickup 5 is moved to a predetermined position by the small gear 11a of the double gear WG toward the turntable 4, and the small gear 11a and the rack gear 5a of the optical pickup 5 are moved. Is disengaged, the cam slider 7 is slightly moved to the left, the fourth gear 8d is rotated slightly, the third gear 8c and the fourth gear 8d are meshed, and the driving force is transmitted to the fourth gear 8d. . Therefore, the cam slider 7 further moves to the left. With this movement, the traverse chassis 2 is lowered, the chuck of the optical disk is released, the optical disk is placed on the tray 3, and the tray 3 moves slightly forward. The fourth gear 8d meshes with the rack gear 3a of the tray 3, the tray 3 moves forward to a predetermined position, and the optical disk is taken out. When the optical disk is placed on the tray 3 and inserted, the tray 3, the cam slider 7, the traverse chassis 2, and the optical pickup 5 operate in reverse to the above, and the optical disk is chucked by the turntable 4 and the clamper 6.

  In the optical disc apparatus described above, the double gear WG of the present invention incorporated as the first gear of the driving force transmission gear mechanism 8 is a double gear having a backlash removing function, as shown in FIGS. Further, the lower gear 11 (main gear) made of synthetic resin, the upper gear 12 (secondary gear) made of the same synthetic resin, and a coil spring 13 are included.

  The lower main gear 11 is integrally formed with a small gear 11a for moving the optical pickup meshing with the rack gear 5a of the optical pickup 5 on the upper surface of the central portion thereof. A small gear 11b for driving the gear meshing with the two teeth 8b is integrally formed. An annular convex portion 11c for reducing the frictional resistance with the upper auxiliary gear 12 is formed on the outer peripheral edge of the main gear 11. Is formed.

  Inside the annular convex portion 11c of the main gear 11, a spring accommodating opening 11d for accommodating the lower half of the coil spring 13 and two arcuate openings 11e and 11e curved in an arc shape are formed. A boss portion 11f that supports one end of the coil spring 13 protrudes inward from one end of the spring accommodating opening 11d. Then, from one end of each arcuate opening 11e, an engagement piece 11g that curves in an arc shape slightly narrower than the width of the arcuate opening 11e projects so as to cover the upper surface of one side of the arcuate opening 11e. Has been. The engaging piece 11g will be described in detail later.

  On the other hand, a circular opening 12a through which the small gear 11a for moving the optical pickup of the main gear 11 is inserted is formed at the center of the upper auxiliary gear 12. And the spring accommodation opening part 12b which accommodates the upper half of the coil spring 13 is formed in the location corresponding to the said spring accommodation opening part 11d of this subgear 12, and the other end of this spring accommodation opening part 12b is formed. The boss portion 12c that supports the other end of the coil spring 13 protrudes inward.

  Further, the auxiliary gear 12 is formed with two arc-shaped openings 12d and 12d having the same width and length as the arc-shaped opening 11e, and the other end of each arc-shaped opening 12d. Thus, an engaged piece 12e that curves in an arc shape slightly narrower than the width of the arc-shaped opening 12d is provided so as to cover the lower surface on one side of the arc-shaped opening 12d. The engaged piece 12e is formed at a position corresponding to the engaging piece 11g of the auxiliary gear 12, and when the double gear WG is assembled by overlapping the main gear 11 and the auxiliary gear 12 as described later, The engaging piece 11g and the engaged piece 12e are elastically engaged.

  This double gear WG is assembled in the following manner. That is, the small gear 11a for moving the optical pickup of the lower main gear 11 is inserted from below into the circular opening 12a of the upper sub gear 12, and the two engagement pieces 11g, 11g of the main gear 11 are connected to the sub gear 12. Are inserted from below into the two arcuate openings 12d, 12d, the main gear 11 and the sub gear 12 are overlapped, and the main gear 11 and the sub gear 12 are relatively rotated to thereby rotate the main gear 11 and the sub gear. Engagement pieces 11g, 11g and engaged pieces 12e, 12e are vertically engaged so that 12 is not separated. Then, the coil spring 13 is accommodated in the spring accommodating openings 12b and 11d in a compressed state, and both ends of the coil spring 13 are supported by the bosses 12c and 11f so as not to fall off. The auxiliary gear 12 is urged in the opposite directions (in this embodiment, the main gear 11 is turned clockwise and the auxiliary gear 12 is turned counterclockwise so that the engaging piece 11g and the engaged piece 12e are not disengaged). The teeth 11h of the main gear 11 and the teeth 12f of the auxiliary gear 12 are assembled so as to be displaced in the circumferential direction.

  When the engaging piece 11g of the main gear 11 is overlapped and engaged with the engaged piece 12e as described above, the inclined tip 11i of the engaging piece 11g is covered as shown in FIG. The engaging piece 12e is pressed downward to form a spring piece that urges the lower main gear 11 and the upper auxiliary gear 12 to always come into contact with each other. That is, before the engagement piece 11g is engaged with the engaged piece 12e, the lower end of the inclined tip portion 11i is lower than the upper surface of the engaged piece 12e, as indicated by a virtual line in FIG. As shown in FIG. 5, when the engagement piece 12 e is elastically engaged with the engagement piece 12 e as shown in FIG. 5, the engagement piece 12 e is pressed by the inclined tip portion 11 i of the engagement piece 11 g and the upper side. The secondary gear 12 is always urged in the direction of being attracted to the lower main gear 11.

  Therefore, this double gear WG has no backlash between the lower main gear 11 and the upper sub gear 12, so that the main gear 11 and the sub gear 12 do not move apart in the vertical direction or approach each other. The teeth 11h and 12f are stably engaged with the output gear 10 of the drive motor M2, and the small gear 11a for moving the optical pickup and the small gear 11b for driving other gears are also used for the rack gear 5a and the driving force transmission gear of the optical pickup 5. Since the second gear 8b of the mechanism 8 meshes stably, noise (noise) generated during meshing is greatly reduced. As described above, the double gear WG shown in FIGS. 3 and 4 does not need to paste a nonwoven fabric or the like that absorbs backlash between the main gear 11 and the sub gear 12, so the number of parts and the number of assembly steps are reduced. The increase in manufacturing cost can be suppressed without increasing.

  Further, since the engaging piece 11g of the double gear WG includes an inclined tip portion 11i that elastically contacts the engaged piece 12e, the lower end of the inclined tip portion 11i is in line contact with the engaged piece 12e. The engaged piece 12e can be intensively pressed, and there is almost no increase in frictional resistance when the backlash is removed by the relative rotation of the upper and lower gears 12 and 11, so the backlash removal function There are no worries about adversely affecting your health. In addition, the downward leading end slope 11j of the inclined tip portion 11i of the engaging piece 11g is used when the upper and lower gears 12, 11 are relatively rotated to engage the engaging piece 11g with the engaged piece 12e. Since it becomes a guide slope, there exists an advantage which can perform an engagement operation | work easily.

  The shape of the engaging piece 11g formed on the spring piece is not limited to the shape having the inclined tip portion 11i as described above, and may be a shape as shown in FIG. 6, for example. That is, the engaging piece 11g is provided with a substantially hemispherical projection 11k elastically contacting the engaged piece 12e on the lower surface of the tip portion, and before the engaging piece 11g is engaged with the engaged piece 12e. 6 is formed so that the protrusion 11k is positioned below the upper surface of the engaged piece 12e, as shown by the phantom line in FIG. 6, and the engaging piece 11g as shown in FIG. When engaged on 12e, the projecting portion 11k is brought into point contact and intensively presses the engaged piece 12e, and urges the upper auxiliary gear 12 to be attracted to the lower main gear 11. is there.

  The engaging piece 11g formed with such a protruding portion 11k also makes point contact with the engaged piece 12e, so that when the backlash is removed by the relative rotation of the upper and lower gears 12 and 11, There is almost no increase in frictional resistance, and when the upper and lower gears 12 and 11 are relatively rotated to engage the engagement piece 11g with the engagement piece 12e, the protrusion 11k is engaged with the engagement piece 12e. Since it easily rides on the upper surface, there is an advantage that the engaging work can be easily performed.

  In the double gear WG of the above embodiment, the engaging piece 11g of the lower main gear 11 is formed as a spring piece and elastically engaged with the engaged piece 12e of the upper auxiliary gear 12 vertically. On the contrary, the engaged piece 12e of the upper auxiliary gear 12 may be formed as a spring piece and elastically engaged with the engaging piece 11g of the lower main gear 11. Further, three or more arcuate openings 12d and 11e are formed in the upper and lower gears 12 and 11, respectively, and an engaged piece 12e is formed at one end of each arcuate opening 12d, and each arcuate shape You may form the engagement piece 11g in the other end of the opening part 11e.

  The double gear of the present invention has been described above by taking the double gear incorporated in the driving force transmission gear mechanism of the optical disk device as an example. However, the double gear of the present invention is incorporated in various devices other than the optical disk device. The noise (noise) at the time of meshing can be reduced.

It is a top view which shows an example of the optical disk apparatus incorporating the double gear of this invention. FIG. 3 is a perspective plan view of the same optical disc apparatus showing the tray in perspective. It is a perspective view of the double gear concerning one embodiment of the present invention. It is a disassembled perspective view of the same double gear. FIG. 4 is an enlarged partial sectional view taken along line AA in FIG. 3. It is an expanded partial sectional view of the double gear concerning other embodiments of the present invention.

Explanation of symbols

WG Double gear 11 Lower gear (main gear)
11a Small gear for moving optical pickup 11b Small gear for driving other gear 11e Arc-shaped opening 11g Engagement piece 11h Teeth 11i Inclined tip of engagement piece 11k Projection of engagement piece 12 Upper gear (sub gear) )
12a Circular opening 12d Arc-shaped opening 12e Engagement piece 12f Teeth

Claims (4)

The upper and lower gears overlap each other so that the upper and lower gears separate the engagement pieces formed at least at two locations on one gear and the engaged pieces formed at locations corresponding to the engagement pieces on the other gear. In the double gear that is engaged in the vertical direction so as not to urge the upper and lower gears so that the teeth of the upper and lower gears are shifted in the circumferential direction,
A small gear for moving the optical pickup and a small gear for driving other gears are formed on the upper surface and the lower surface of the central portion of the lower gear, respectively, and a circular opening is formed in the central portion of the upper gear. A small gear for moving the pickup is inserted into the circular opening, and one of the engagement piece and the engagement piece is formed as a spring piece, and the engagement piece and the engagement piece are elastically engaged. A double gear for an optical disk device, characterized in that The upper and lower gears overlap each other so that the upper and lower gears separate the engagement pieces formed at least at two locations on one gear and the engaged pieces formed at locations corresponding to the engagement pieces on the other gear. In the double gear that is engaged in the vertical direction so as not to urge the upper and lower gears so that the teeth of the upper and lower gears are shifted in the circumferential direction,
One of the engagement piece and the engagement piece is formed as a spring piece, and the engagement piece and the engagement piece are elastically engaged with each other.   One of the engagement piece or the engagement piece formed on the spring piece includes an inclined tip portion that elastically contacts the other engagement piece or the engagement piece. 2. The double gear according to 2.   3. One of the engagement pieces or the engagement pieces formed on the spring piece is provided with a protrusion that elastically contacts the other engagement piece or the engagement piece. Double gear as described in.

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