JPH09121507A - Geared motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the detection accuracy of a rotational angle detecting section which detects the rotational angle of a geared motor and to reduce the thickness of the detecting section by fitting a galvanomagnetic element to a fitting hole formed in a flexible substrate at the position facing an output gear so that the element can be faced to the output gear. SOLUTION: The Hall IC 12 of a geared motor can be mounted on a flexible substrate 14 through simple work without requiring any positioning jig, because the IC 12 is mounted on the substrate 14 in such a way that the main body 12a of the IC 12 is put in a mounting hole 18 formed through the substrate 14 and a backing plate 16 and the main body 12a is positioned to the hole 18. In addition, since the dimensional accuracy of the hole 18 formed through the substrate 14 can be improved and the mounting error of the IC 12 can be reduced, the positioning accuracy of the IC 12 is improved and the detection accuracy of the rotational angle detecting section which detects the rotational angle of an output gear can be improved. Moreover, since the IC 12 is mounted on the substrate 14 by putting the main body of the IC 12 in the mounting hole 18 of the substrate 14, the thickness of the detecting section can be reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a geared motor, and more particularly, to a geared motor suitable for performing, for example, loading or ejecting a recording medium of a magneto-optical disk device.

[0002]

2. Description of the Related Art FIG. 11 shows a geared motor 50 of a conventional example.
FIG. 12 is a bottom view of the geared motor 50 with the cover 51 removed.

As shown in FIG. 12, a drive shaft 55 of a motor 54 projects into a gear box 53 composed of a frame 52 and a cover 51, and the rotation of the drive shaft 55 consists of a plurality of gears 56 to 58. The operation pin 60a shown in FIG. 11 is transmitted to the final output gear 60 via the gear mechanism 59 and is projected on the upper surface side of the output gear 60.
However, a recording medium is loaded and ejected by operating a lever (not shown).

As shown in FIG. 12, a magnet 61 is provided on the lower surface side of the output gear 60, and a Hall IC 63 is mounted on a circuit board 62 facing the lower surface of the output gear 60. The magnet 61 and the Hall IC 63 constitute a rotation angle detection unit that detects the rotation angle (rotational position) of the output gear 60, and the drive of the motor 54 is controlled based on the detected output.

[0005]

FIG. 13 is a sectional view of the vicinity of the mounting portion of the Hall IC 63 shown in FIG.

In the conventional geared motor 50, the hall I
When the C63 is manually mounted on the circuit board 62, the Hall IC 63 is placed on the circuit board 62, and the Hall IC 63 is positioned and soldered by using the positioning jig 64. .

As described above, since the Hall IC 63 is manually mounted using the positioning jig 64, the mounting position of the Hall IC 63 varies due to the positioning error of the jig 64, and the rotation angle of the output gear 60 varies. There is a problem in that the detection also varies, and the workability is poor because the positioning jig 64 is used.

Further, the Hall IC 63 is provided on the circuit board 62.
As a result, the rotation angle detection part becomes thicker and the geared motor becomes larger, so especially in geared motors with large torque, the rotation angle is reduced in order to reduce the size. It is desirable to make the thickness of the angle detection unit as thin as possible.

The present invention has been made in view of the above points, and improves the accuracy of detecting the rotation angle of the geared motor, improves the assembly workability, and reduces the cost. The purpose is to reduce the thickness of the detection unit.

[0010]

In order to achieve the above-mentioned object, the present invention is configured as follows.

That is, in the geared motor of the present invention, an output gear and a gear mechanism for transmitting rotation from the motor are incorporated in the gear box, a flexible board is incorporated, and a magnet is provided in the output gear. In addition, the flexible substrate,
A mounting hole is formed at a position facing the output gear, and the magnetoelectric conversion element is mounted in the mounting hole so as to face the output gear.

The magnetoelectric conversion element may be a Hall element or a Hall IC including a Hall element and an amplifier circuit.

The flexible substrate may be reinforced with a backing plate at required portions other than the portion requiring flexibility.

The mounting hole may have a shape corresponding to the outer shape of the main body of the magnetoelectric conversion element, and the lead terminal may be soldered to the flexible substrate with the main body of the magnetoelectric conversion element fitted in the mounting hole.

Further, the gear box is composed of a frame and a cover, the frame has an opening for pulling out the flexible substrate to the outside of the gear box, and the cover attaches the cover to the frame. A restricting portion may be provided that abuts on the flexible board that passes through the opening and restricts the position at which the flexible board is pulled out of the opening.

[0016]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is an external perspective view of a geared motor according to the present invention, and FIG. 2 is a bottom view of the state where the cover 3 of FIG. 1 is removed.

The geared motor 1 of this embodiment is for loading or ejecting a recording medium in a magneto-optical disk device. The geared motor 1 has a torque larger than that of the conventional example described above.
It has a structure corresponding to.

In this geared motor 1, a drive shaft of a motor 5 projects into a gear box 4 composed of a frame 2 and a cover 3, and the rotation of the drive shaft is composed of a plurality of gears 6 to 8. It is configured to be transmitted to the final output gear 9 via 10. That is, as shown in FIG. 2, a gear (not shown) integrated with the drive shaft of the motor 5 meshes with the large-diameter gear of the first gear 6, and the small-diameter gear of the first gear 6 becomes the first gear. The small diameter gear of the second gear 7 meshes with the large diameter gear of the third gear 8, and the small diameter gear of the third gear 8 meshes with the output gear 9. doing.

The operation pin 9a shown in FIG. 1 projecting from the upper surface of the final output gear 9 operates a lever (not shown) to load or eject the recording medium.

A magnet 11 is provided on the lower surface side of the output gear 9 as shown in FIG.
A Hall IC 12 is provided at a position facing the lower surface of the output gear 9 as will be described later.
1 and the Hall IC 12 constitute a rotation angle detector 13 for detecting the rotation angle (rotational position) of the output gear 9, and the drive of the motor 5 is controlled based on the detected output. In addition, as another embodiment of the present invention, a Hall element may be used instead of the Hall IC 12.

The geared motor 1 of this embodiment is shown in FIG.
Instead of the conventional circuit board 62 shown in FIG. 2, required parts of a flexible printed wiring board (hereinafter referred to as “flexible board”) 14 in which a conductor pattern is formed on the surface of a flexible insulating film are reinforced with a backing board. Hall IC 12 that uses a substrate and constitutes the rotation angle detection unit 13
As will be described later, is mounted with the main body part dropped into the mounting holes formed through the flexible substrate 14 and the backing plate.

FIG. 3 is a plan view showing a state where the Hall IC 12 is mounted on the flexible substrate 14, and FIG.
It is sectional drawing seen from the cutting surface line AA.

The flexible board 14 is provided in a portion where flexibility is required to draw the flexible board 14 out of the gear box 4, that is, in a required portion other than the drawn portion 15 in a range indicated by W in FIG. The backing plate described above is adhered to increase the mechanical strength. Further, the flexible board 14 is formed with through holes 19 and 20 for positioning when the flexible board 14 is attached to the frame 2, and a connector is provided at the free end of the lead-out portion 15 to which the backing plate is not adhered. A section 17 is provided.

This flexible substrate 14 and backing plate 1
As shown in FIG. 4, a penetrating mounting hole 18 for mounting the Hall IC 12 is formed in 6, and the mounting hole 18 of the output gear 9 when assembled in the gear box 4 is formed. It is formed at a predetermined position facing the surface on which the magnet 11 is provided, and the mounting hole 18 has a rectangular shape corresponding to the main body 12a of the Hall IC 12.

In the geared motor 1 of this embodiment, the mounting holes 18 for the flexible substrate 14 and the backing plate 16 are provided.
Inside the main body 1 of the Hall IC 12, as shown in FIG.
While dropping 2a and fitting it, this main body 12a
The lead terminals 12b extending horizontally from the outside are soldered to the flexible substrate 14.

As described above, the mounting hole 18 has a shape corresponding to the outer shape of the main body 12a of the Hall IC 12, and the mounting position of the Hall IC 12 is defined by dropping the Hall IC 12 into the mounting hole 18. Is configured to.

That is, in this geared motor 1, the Hall IC 12 is mounted on the flexible substrate 14 by inserting the main body 12a portion of the Hall IC 12 into the mounting hole 18 formed in the flexible substrate 14 and the backing plate 16. 18 and the main body 12a of the Hall IC 12 are used for positioning, so that it is not necessary to position the Hall IC using the positioning jig 64 as in the conventional case, and the mounting work is simplified. become. Moreover, since the flexible board 14 can improve the dimensional accuracy of the mounting holes 18 as compared with the conventional circuit board 62, the error in the mounting position can be reduced as compared with the mounting using the positioning jig 64. As a result, the positioning accuracy of the Hall IC 12 is increased and the accuracy of detecting the rotation angle of the output gear 9 is increased.

Further, since the main body 12a of the Hall IC 12 is mounted in the mounting hole 18 of the flexible board 14 reinforced by the backing plate 16 in a state of being dropped, the Hall IC is mounted and mounted on the circuit board 62 in the conventional case. It is possible to reduce the thickness of the rotation angle detection unit 13 as compared with the example.

The flexible board 14 has through holes 19 and 20 for positioning when it is attached to the frame 2 as described above, and the through holes 19 and 20 are provided with projections formed on the frame 2 which will be described later. The flexible substrate 14 is attached to the frame 2 so as to be inserted therethrough.
Compared with the conventional circuit board 62, the through holes 19, 2
The dimensional tolerance of 0 can be reduced, and the positioning accuracy of the flexible substrate 14 with respect to the frame 2 can be increased. As another embodiment of the present invention, the backing plate 16 may be omitted.

FIG. 5 is a plan view of the frame 2 constituting the gear box 4, FIG. 6 is a bottom view thereof, and FIG.
6 is a cross-sectional view taken along the section line ABCD of FIG. 6, and the configuration of the frame 2 will be described in detail with reference to these figures and FIG. 1.

The frame 2 is formed with a large-diameter circular opening 23 facing a part of the output gear 9 and the operating pin 9a projecting from the output gear 9, and the drive shaft of the motor 5 is A circular small-diameter opening 24 is formed for insertion. On the upper surface side of the frame 2, three locking portions 25 for locking and fixing the motor 5 are provided in a protruding manner.

Engagement protrusions 29 are formed on the side surfaces of the frame 2 at required positions.
The frame 2 and the cover 3 are integrally assembled by engaging a later-described gate-shaped hook formed on the cover 3. Further, at three corners of the frame 2, there are mounting portions 70 to 70 each having a mounting hole for mounting the geared motor 1 at a required position.
72 are formed.

On the other hand, on the lower surface side of the frame 2, that is, on the side where the cover 3 is attached, the Hall IC 1 of the output gear 9, the gear mechanism 10 and the flexible substrate 14 described above.
The first storage concave portion 26 in which the portion on which 2 is mounted is incorporated and the second storage concave portion 27 in which the remaining portion of the flexible substrate 14 is incorporated are configured.
As shown in FIG. 6, the first storage recess 26 includes the output gear 9 and the first to third of the gear mechanism 10 incorporated therein.
Of the gears 6 to 8 are formed along a part of the tip circle of each gear 6 to 8, and the inner wall 41 corresponding to the output gear 9 and the first to third
Has inner walls 42 to 45 corresponding to the respective gears 6 to 8. A support shaft 28 corresponding to the first gear 6 is formed in the first storage recess 26, and support shafts corresponding to the second and third gears 7 and 8 are also provided in a protruding manner.

Further, the frame 2 is provided with cylindrical projections 21 and 22 for positioning the flexible substrate 14 and the cover 3 described above.

The second storage recess 27 is formed with an opening 30 for drawing out the flexible drawn-out portion of the flexible board 14 to the outside of the gear box 4. The opening 30 draws out the flexible board 14. The size of the flexible substrate 14 is large enough to facilitate the pulling out work of the flexible substrate 14.

In the geared motor 1 of this embodiment, in order to firmly fix the frame 2 and the cover 3 so that rattling does not occur due to the radial force acting during the operation, the first frame 2 of the frame 2 is prevented. The inner wall of the storage recess 26 is formed concentrically along the addendum circles of the gears 6 and 9 as described above, and the first storage recess 26 and the cover 3 fitted into the first storage recess 26 are formed. The so-called spigot, which is a fitting portion, is formed by the convex portion described later.

FIG. 8 is a plan view of the cover 3, and FIG.
FIG. 9 is a sectional view taken along the section line ABCDE of FIG.
The configuration of the cover 3 will be described in detail with reference to these figures and FIG.

The cover 3 is provided with each gear 6 to 6 of the gear mechanism 10.
8 and a circular support recess 3 corresponding to the support shaft of the output gear 9
1 to 34 are formed and the protrusion 2 of the frame 2 is formed.
Fitting recesses 35 and 36 corresponding to 1 and 22 are formed.

Further, a gate-shaped hook 46 that engages with the engagement protrusion 29 of the frame 2 is provided at a required position on the peripheral portion of the cover 3 so as to project therefrom.

The cover 3 is formed with arcuate convex portions 37 _{1 to 3} , 38 which are fitted into the first accommodating concave portion 26 of the frame 2 and have a large diameter arcuate convex portion 37. _1-3 are
The small-diameter arc-shaped second convex portion 38, which is fitted along the inner wall 41 corresponding to the output gear 9 of the first storage concave portion 26 shown in FIG. 6, is attached to the first gear 6 of the first storage concave portion 26. It is configured to fit along the corresponding inner wall 42. In addition, convex portions 39, 40 having a circular arc shape having a medium diameter are formed as reinforcing ribs.

Thus, the frame 2 is formed with the first storage recess 26, and the cover 3 is provided with the first storage recess 26.
Since the projections 37 _{1 to 3} and 38 that fit along the inner walls 41 and 42 of the storage recess 26 are formed to form the spigot that is the fitting portion, the frame 2 and the cover 3 configure the gear box 4. At this time, the frame 2 and the cover 3 can be firmly fixed to each other, and the frame 2 and the cover 3 are separated from each other even when a radial force that tries to shift the frame 2 and the cover 3 from each other is applied during operation. There is no rattling.

Moreover, since the fitting portion is provided concentrically with the gears 6 and 9 incorporated in the gear box 4, the positioning accuracy is improved and the gear assembling work is facilitated.

As another embodiment of the present invention, the fitting portion does not have to be concentric with the gears 6 and 9.

The cover 3 is provided with a restricting portion 47 for restricting the pulling-out position of the flexible board 14 which is pulled out from the opening 30 of the frame 2 as shown in FIG. , Frame 2 and cover 3
When the gear box 4 is constructed by assembling the above, the restricting portion 47 located inside the gear box 4 contacts the lower surface of the flexible board 14 to define the pull-out height of the flexible board 14 in the opening 30 of the frame 2. It will be.

By restricting the pull-out height of the flexible board 14 in this way, when the geared motor 1 is mounted at a required position, the flexible board 14 covers the upper part of the mounting portion 70 and the mounting work with screws or the like. Can be effectively prevented.

[0047]

As described above, according to the present invention, since the magnetoelectric conversion element such as the Hall IC facing the output gear provided with the magnet is mounted in the mounting hole formed in the flexible substrate, the circuit board is mounted. Compared to the conventional example to be implemented,
The thickness of the rotation angle detection part of the output gear can be made thinner, and a flexible board with higher dimensional accuracy than the conventional circuit board must be used, and the mounting hole must have a shape corresponding to the outer shape of the main body of the magnetoelectric conversion element As a result, the body of the magnetoelectric conversion element is fitted into the mounting hole to position the magnetoelectric conversion element.Therefore, it is not necessary to use a positioning jig as in the conventional example, and the work is simplified. To be done.

Further, an opening for pulling out the flexible substrate to the outside of the gear box is formed in the frame constituting the gear box, and a flexibility for inserting the opening in the cover by attaching the cover to the frame. Since the restriction portion for contacting the flexible board and restricting the drawing position of the flexible board in the opening is provided, the opening for drawing out the flexible board can be enlarged to facilitate the work of drawing the flexible board. In addition, it is possible to set the pulling-out position of the flexible substrate to a desired position by the restriction section.

[Brief description of the drawings]

FIG. 1 is an external perspective view of a geared motor according to the present invention.

FIG. 2 is a bottom view of the geared motor of FIG. 1 with a cover removed.

FIG. 3 is a plan view of a flexible board on which a Hall IC is mounted.

FIG. 4 is a sectional view taken along line AA of FIG. 3;

5 is a plan view of the frame of the geared motor of FIG. 1. FIG.

6 is a bottom view of the frame of FIG.

FIG. 7 is a cross-sectional view taken along the section line ABCD of FIG.

FIG. 8 is a plan view of a cover of the geared motor of FIG.

9 is a sectional view taken along the section line ABCDE of FIG.

10 is a partial cross-sectional view of a drawn-out portion of a flexible substrate of the geared motor of FIG.

FIG. 11 is an external perspective view of a geared motor of a conventional example.

12 is a bottom view of the geared motor of FIG. 11 with a cover removed.

FIG. 13 is a sectional view of the vicinity of a mounting portion of a conventional Hall IC.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Geared motor 2 Frame 3 Cover 9 Output gear 10 Gear mechanism 11 Magnet 12 Hall IC 14 Flexible board 18 Mounting hole 26 1st storage recessed part 30 Opening part 37 _1-3 , 38 Convex part

Claims (5)

[Claims] 1. A gearbox includes an output gear, a gear mechanism for transmitting rotation from a motor to the output gear, a flexible substrate, a magnet provided on the output gear, and the flexible substrate. Is a geared motor in which a mounting hole is formed at a position facing the output gear, and the magnetoelectric conversion element is mounted in the mounting hole so as to face the output gear. 2. The geared motor according to claim 1, wherein the magnetoelectric conversion element is a Hall element or a Hall IC. 3. The geared motor according to claim 1, wherein a required portion of the flexible substrate is reinforced by a backing plate. 4. The magnetoelectric conversion element has a main body and lead terminals extending horizontally from the main body, and the mounting hole of the flexible substrate has a shape corresponding to the outer shape of the main body of the magnetoelectric conversion element. The geared motor according to any one of claims 1 to 3, wherein the lead terminals of the magnetoelectric conversion element are soldered to the flexible substrate in a state where the main body is fitted into the mounting hole of the flexible substrate. 5. The gearbox is composed of a frame and a cover, the frame has an opening for pulling out a flexible substrate to the outside of the gearbox, and the cover is provided with the cover by attaching the cover to the frame. The geared motor according to any one of claims 1 to 4, wherein the geared motor has a restricting portion that abuts on a flexible board that passes through the opening and restricts a drawing position of the flexible board in the opening.