JPH1130309A - Gear device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively utilize a space in whcih gears are arranged and miniaturize a gear device and an apparatus with a gear device such as a recording/ reproducing apparatus as well. SOLUTION: A gear device is provided with a motor 19 a first gear 20 fixed to a revolving shaft 19a of the motor 19, a gear group 25, which includes a plurality of intermediate gears 22, 23 and which is engaged with the first gear 20, and a second gear 24, which is fixed on one end side of a shaft member 6 and which is engaged with the gear group 25. The above gears are arranged within a disposing space 18, and one end surface of a gear shaft 21 of one gear out of the gear group 25 is formed as a thrust receiving part 21a, which receives the end surface of the shaft member 6 on the side on which the second gear 24 is fixed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a gear device.
More specifically, the present invention relates to a technique for effectively utilizing an arrangement space in which gears are arranged, and for reducing the size of a gear device, and further, a device including a gear device, for example, a recording and reproducing device.

[0002]

2. Description of the Related Art For example, there is an MD recording / reproducing apparatus for recording / reproducing a recording / reproducing medium for recording / reproducing or both of them, for example, an MD (mini disc).

An MD recording / reproducing apparatus has a mechanical chassis on which required members such as an optical pickup and a turntable are arranged, and the mechanical chassis is provided with the optical pickup in a radial direction of an MD mounted on the turntable. Is provided with a feed mechanism.

The feed mechanism is provided with a gear device having a motor and a plurality of gears arranged in a gear disposition section, and a plurality of gears are connected to a feed screw screwed with a nut member provided on a moving base of the optical pickup. One of the gears is fixed,
The torque of the motor is transmitted to the feed screw via a gear group, whereby the nut member moves in the axial direction of the feed screw, that is,
The optical pickup moves in the radial direction of the MD and moves.

[0005] In such a gear device provided in the feed mechanism of the optical pickup, the motor is small (thin).
In some cases, the thickness of the MD recording / reproducing apparatus is reduced. When a small motor is used, the torque is reduced, so that the number of gears interposed between the gear fixed to the motor and the gear fixed to the feed screw, for example, the number of stepped gears is reduced. It is conceivable to increase the speed reduction ratio by increasing the number of gears. However, if all of these gears are arranged in parallel, the size of the gear in the gear arrangement direction in one direction, that is, the MD recording in that direction, The size of the playback device becomes unnecessarily large. Therefore, it is conceivable to change the arrangement of the gears so that the size in one direction does not become larger than necessary.

FIG. 5 schematically shows such a gear device.

A mechanical chassis (not shown) is provided with a support member a. The support member a is formed integrally with a thrust receiving portion b, a gear disposition portion c having an opening, and a connection portion d for connecting these components. Become. The opening of the gear disposition portion c is formed on the opposite side of the thrust receiving portion b, and the disposition space f is formed by covering the opening with the motor mounting plate e.

A motor g is mounted on the motor mounting plate e, and a motor-side gear i fixed to the end of the rotation shaft h is disposed in the arrangement space f.

A feed screw j rotatably supported by the support member a is provided with a screw shaft portion k, and a feed screw side gear 1 is fixed to a portion where the screw shaft portion k is not formed. The feed screw side gear 1 is arranged in the arrangement space f, and one end of the feed screw j arranged in the arrangement space f has a preload spring n attached to an attachment portion m provided in the arrangement space f.
Is in elastic contact. As a result, the moving force toward the other end is urged to the feed screw j, and the other end of the feed screw j is supported in a state of being in contact with the thrust receiving portion b of the support member a.

[0010] The feed screw side gear l fixed to the feed screw j
Is meshed with the motor-side gear i via intermediate gears o and p arranged in the arrangement space f. Then, the feed screw side gear 1 and the intermediate gear o meshing therewith, the motor side gear i and the intermediate gear p meshing therewith, the intermediate gear o and the intermediate gear p respectively correspond to the X direction ( The vertical direction or the horizontal direction, which is a direction perpendicular to the thickness direction of the MD recording / reproducing device.) The feed screw side gear 1 and the intermediate gear p, the motor side gear i and the intermediate gear o
Are arranged in the Y direction (the direction orthogonal to the thickness direction of the MD recording / reproducing apparatus and the direction orthogonal to the X direction) shown in FIG.

By arranging the gears i, l, o, and p in this way, the motor g can be made small (thin) to increase the reduction ratio when the MD recording / reproducing apparatus is made thin. Even if the number of gears is increased, only one of the longitudinal direction and the lateral direction (X direction or Y direction) of the MD recording / reproducing apparatus is prevented from becoming unnecessarily large.

A nut member provided on a moving base of an optical pickup (not shown) is screwed into the screw shaft portion k of the feed screw j, and the feed screw j is rotated by the rotation of the motor g. The optical pickup is moved by being fed in the axial direction of the feed screw j, that is, in the radial direction of the MD.

[0013]

By the way, in the gear device described above, although the thickness of the device can be reduced, the arrangement space f, which is a narrow space in which a plurality of gears i, l, o, and p are arranged, is provided. The mounting part m and the preload spring n attached to the mounting part m are provided therein, and there is a problem that workability of mounting the preload spring n to the mounting part m is poor.

Further, since the preload spring n is arranged in the narrow arrangement space f, the size of the gear is restricted by the arrangement of the preload spring n, which hinders obtaining a high reduction ratio.

Accordingly, the gear device of the present invention overcomes the above-mentioned problems, and makes effective use of the arrangement space in which the gears are arranged.
It is an object to reduce the size of a recording and reproducing device.

[0016]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, a gear device of the present invention meshes with a motor, a first gear fixed to a rotating shaft of the motor, and the first gear. A gear group, and a second gear fixed to one end of the shaft member and meshing with the gear group, wherein each of the gears is arranged in an arrangement space, and a gear shaft of one of the gears in the gear group is provided. One end face is formed as a thrust receiving portion for receiving the end face of the shaft member on the side where the second gear is fixed.

Therefore, the gear device of the present invention can effectively utilize the arrangement space in which the gears are arranged.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the gear device according to the present invention will be described below with reference to the accompanying drawings. In the embodiment described below, the present invention is applied to a portable MD (mini disc).
This is applied to a playback device.

In this specification, the direction indicated by arrow F in FIG. 1 will be described as the front, the direction indicated by arrow B after, the direction indicated by arrow R to the right, and the direction indicated by arrow L to the left.

A rectangular and rectangular mechanical chassis 1 is supported in an outer casing (not shown) of the MD reproducing apparatus, and a turntable (not shown), an optical pickup 2, and a turntable (not shown) are mounted on the mechanical chassis 1. A feed mechanism 3 for moving the MD mounted on the table in the radial direction is disposed (see FIG. 1).

An opening 1 a is formed in a part of the mechanical chassis 1, and guide shafts 4, 4 extending in the left-right direction for guiding the optical pickup 2 when it moves are provided on the lower surface of both side edges of the opening 1 a. Is provided. The guide shafts 4, 4 support slidably supported portions formed at both front and rear ends of the optical pickup 2.

A feed mechanism 3 is provided at the rear end of the lower surface of the mechanical chassis 1 (see FIG. 1). The feed mechanism 3 includes the above-described guide shafts 4 and 4 and a support member 5 and a feed mechanism. A screw 6, a motor mounting plate 7, and a gear device 8 are provided (see FIG. 2).

The supporting member 5 is formed integrally with a spring supporting portion 9 formed at the left end thereof, a gear disposing portion 10 formed at the right end thereof, and a connecting portion 11 which is long in the left-right direction and connects them. The gear disposition portion 10 is opened on the right and lower sides. The front ends of the spring support portion 9 and the gear disposition portion 10 are formed to project slightly forward, respectively, and the one guide shaft 4 is positioned so as to bridge between them.

A support hole 9a through which one end of the feed screw 6 passes is formed in the spring support portion 9 (see FIG. 4). The gear disposition portion 10 has a bearing groove 10a opened upward and supporting the other end of the feed screw 6, and a locking projection 10b formed on the rear surface (see FIG. 4).

A preload spring 12 is supported on the upper surface side of the spring support portion 9, and the preload spring 12 is formed with a preload portion 12a for resiliently pressing the feed screw 6 in the thrust direction. 2).

The left and right ends of the feed screw 6 are formed to have a slightly smaller diameter than the intermediate portion 13 which is the remaining portion, and the portion excluding the both ends of the intermediate portion 13 is formed with a screw shaft portion 13a having a thread groove. Have been. The feed screw 6 has a left end portion penetrated through the support hole 9a of the support member 5, a right end portion of the intermediate portion 13 supported by the bearing groove 10a of the support member 5, and extends along the connecting portion 11 of the support member 5. (See FIG. 4). When the feed screw 6 is supported by the support member 5, the distal end of the preload portion 12 a of the preload spring 12 is elastically contacted with the left end of the feed screw 6. Rightward movement is being applied.

An engaging projection of a nut member 2a made of a leaf spring material provided on a moving base of the optical pickup 2 is resiliently engaged with the screw shaft portion 13a of the feed screw 6 from above. I have.

As described above, the feed screw 6 is connected to the intermediate portion 1 thereof.
The right end of the nut 3 is rotatably supported by the bearing groove 10a opened upward. However, since the engaging ridge of the nut member 2a is elastically engaged with the feed screw 6 from above, the feed The screw 6 is always pressed downward and pressed against the bearing groove 10a, so that the feed screw 6 does not fall off the support member 5.

Therefore, since the bearing groove 10a of the support member 5 is formed so as to open upward, the amount of movement of the nut member 2a in the left-right direction by the length of the bearing groove 10a in the left-right direction.
As a result, the moving amount of the optical pickup 2 can be increased, and thereby the length of the support member 5 in the left-right direction can be shortened, which contributes to the miniaturization of the MD recording / reproducing apparatus. I do.

The motor mounting plate 7 has an L-shaped support portion at the front end as viewed in a horizontal sectional shape, a motor mounting portion 15 continuous with the supported portion 14 and extending in the front-rear direction. An engaging portion 16 that is continuous with the rear end and extends in the left-right direction (see FIGS. 2 and 3). A screw insertion hole 14a is formed at the front end of the supported portion 14, and the motor mounting portion 1 is formed.
A shaft insertion hole 15a is formed at a position slightly rearward from the center in the front-rear direction of 5, and an engagement hole 16a is formed at the left end of the engagement portion 16.

Thus, the motor mounting plate 7 engages the locking projection 10b of the support member 5 with the engaging hole 16a of the engaging portion 16, and then the mounting screw inserted into the screw insertion hole 14a of the supported portion 14. 17 is attached to the support member 5 by screwing it to the gear disposition portion 10.

As described above, the support member 5 of the motor mounting plate 7
The attachment to the gear mounting portion 10 is performed simply by engaging the engagement hole 16a with the locking protrusion 10b and screwing the attachment screw 17 inserted through the screw insertion hole 14a of the supported portion 14 to the gear disposition portion 10. Installation work is extremely simple.

As described above, the motor mounting plate 7 is
, The opening on the right side of the gear disposition portion 10 is covered by the motor mounting portion 15 of the motor mounting plate 7, and a disposition space 18 is formed here.

The gear unit 8 includes a motor 19 mounted on the motor mounting plate 7 and a plurality of gears arranged in the arrangement space 18 (see FIGS. 2 and 3).

A motor 19 is mounted on the motor mounting portion 15 of the motor mounting plate 7 with its rotary shaft 19a inserted through the shaft insertion hole 15a, and a first gear 20 fixed to the tip of the rotary shaft 19a. Are arranged in the arrangement space 18.

A gear shaft 21 is provided at the front end of the motor mounting portion 15.
Is fixed at its right end, and an intermediate gear 22 formed as a stepped gear (two-step gear) is supported on the gear shaft 21. The large diameter portion 22a of the intermediate gear 22 and the first gear 20 are meshed.

In the arrangement space 18, an intermediate gear 23 formed as a stepped gear (two-step gear) to the left of the first gear 20
The large diameter portion 23a of the intermediate gear 23 is meshed with the small diameter portion 22b of the intermediate gear 22.

The right end of the feed screw 6 has a second gear 2
4 is fixed, and the second gear 24 is
Is disposed to the left of the intermediate gear 22 in the inside. The second gear 24 is meshed with the small diameter portion 23b of the intermediate gear 23.

At the center of the right end face of the second gear 24, a hemispherical contact projection 24a is provided so as to project rightward.
As described above, since the rightward moving force due to the elastic contact of the preload spring 12 is urged to the feed screw 6, the corresponding contact projection 24
a is the left end surface of the gear shaft 21 of the intermediate gear 22, that is, the shaft head 2
1a, so that the right end of the feed screw 6 is supported by the shaft head 21a of the gear shaft 21 via a contact protrusion 24a provided on the second gear 24. That is, the gear shaft 2
The end face of one shaft head 21 a is formed as a thrust receiving portion of the feed screw 6.

As described above, the first gear 20 fixed to the rotation shaft 19a of the motor 19 and the second gear 24 fixed to the feed screw 6 are two stepped gears, that is, the intermediate gear 2
Meshed via a gear group 25 consisting of 2, 23,
As a result, a high reduction ratio is obtained.

When the motor 19 is rotated, the rotational force is applied to the first gear 20, the gear group 25, and the second gear 24.
And the second gear 24 rotates the feed screw 6 to which the second gear 24 is fixed in the direction around the axis. Then, when the feed screw 6 is rotated, the nut member 2a engaged with the screw shaft portion 13a is sent to the left or right in accordance with the rotation direction, whereby the optical pickup 2 moves in the radial direction of the MD. Be moved.

In the gear device 8 described above, the gear shaft 2
Since the end face of the first shaft head 21a is formed as a thrust receiving portion of the feed screw 6, the arrangement space 18 can be effectively used, and the size of the gear is hardly restricted, so that a high reduction ratio can be obtained. This makes it possible to make the motor 19 thinner, so that the MD recording / reproducing apparatus can be made thinner.

A thrust receiving portion for receiving the right end of the feed screw 6 in the arrangement space 18, that is, a shaft head 21 of the gear shaft 21
a, the preload spring 12 for urging the feed screw 6 to move can be arranged on the left end side of the feed screw 6, and the motor 19 can be thinned and arranged in the arrangement space 18. Even when the number is increased, there is no need to attach the preload spring 12 to the arrangement space 18 which is a narrow space.

Accordingly, it is possible to reduce the thickness of the MD recording / reproducing apparatus by reducing the thickness of the motor 19 without lowering the workability.

[0045]

As is apparent from the above description, the gear device of the present invention comprises a motor, a first gear fixed to a rotating shaft of the motor, and a gear group meshing with the first gear. And a second gear fixed to one end of the shaft member and meshing with the gear group, wherein each of the gears is arranged in the arrangement space, and one end face of a gear shaft of one of the gears in the gear group. Is formed as a thrust receiving portion for receiving the end face of the shaft member on the side to which the second gear is fixed, so that the arrangement space in which each gear is arranged can be effectively used, and the size of the gear is hardly restricted. Therefore, it is possible to obtain a high reduction ratio, thereby making it possible to reduce the thickness of the motor and reduce the thickness of a gear device, and further, a device including the gear device, for example, a recording / reproducing device.

Further, since the thrust receiving portion for receiving one end of the feed screw, that is, the end face of the gear shaft is provided in the arrangement space in which the gear is disposed, the moving force is applied to the feed screw on the other end side of the feed screw. Can be arranged, and even when the number of gears arranged in the arrangement space in which the gears are arranged is increased by reducing the thickness of the motor, the arrangement space in which the gears, which are narrow arrangement spaces, are arranged. It is not necessary to attach a preload spring to the vehicle.

Therefore, it is possible to reduce the thickness of a device having a gear device by a thin motor, for example, a recording / reproducing device, without lowering the workability.

It should be noted that the specific shapes and structures of the respective parts shown in the above-described embodiments are merely examples of the embodiment of the present invention.
These should not be construed as limiting the technical scope of the present invention.

[Brief description of the drawings]

FIG. 1 shows an embodiment of a gear device of the present invention together with FIGS. 2 to 4, and is a bottom view showing a mechanical chassis and a feed mechanism provided on the mechanical chassis.

FIG. 2 is an enlarged bottom view showing a main part of the feed mechanism with a partial cross section.

FIG. 3 is an enlarged bottom view partially showing a cross section of the gear device.

FIG. 4 is a cross-sectional view taken along the line IV-IV of FIG. 2 from which a gear, a preload spring, and a motor mounting plate are omitted.

FIG. 5 is an enlarged sectional view showing a gear device in which a preload spring is arranged in an arrangement space.

[Explanation of symbols]

6 ... feed screw (shaft member), 8 ... gear device, 18 ... placement space, 19 ... motor, 19a ... rotary shaft, 20 ... first gear, 21 ... gear shaft, 21a ... shaft head (thrust receiving portion), 2
2 intermediate gear, 23 intermediate gear, 24 second gear, 2
5 ... Gear group

Claims (1)

[Claims] 1. A motor, a first gear fixed to a rotating shaft of the motor, a gear group having a plurality of intermediate gears and meshing with the first gear, fixed to one end of a shaft member And a second gear meshing with the gear group, wherein each of the gears is arranged in the arrangement space, and one end face of the gear shaft of one of the gear groups is fixed by the second gear of the shaft member. A gear device characterized in that it is formed as a thrust receiving portion for receiving an end surface on the side of the gear.