JPH1116183A - Galvanomirror device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a galvanomirror device capable of maintaining the reflecting direction of a luminous flux with high accuracy by preventing an axial part from being tilted in the case of supporting a deflection mirror by a pivotaly supporting method. SOLUTION: A mirror holder 10 having a deflection mirror 11 is freely rotatably supported to a frame 17 of a device main body by a pivotaly supporting method. Namely, bearing parts 12, 13 having conical recessed surfaces 12A, 13A are fixed to the upper and lower parts of the mirror holder 10, the adjacent tips of shaft parts 140, 15 having taper faces are abutted on the adjacent tops of the conical recessed surfaces 12A, 13A and the mirror holder 10 is freely rotatably supported. A circular projected part 140C is formed on the upper surface of the shaft part 140 and the circular projected part 140C is engaged with a through hole formed in a leaf spring 22. Consequently, the shaft part 140 is coupled to the leaf spring 22.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a galvanomirror device used as an optical deflector in an optical information recording / reproducing apparatus or the like.

[0002]

2. Description of the Related Art As a conventional galvanometer mirror device, for example, one described in Japanese Patent Application Laid-Open No. 64-2015 is known. As shown in FIG. 10, the galvanomirror device includes a deflecting mirror 1 and a support member 2 that rotatably supports the deflecting mirror 1. The support member 2 is fixed to a base 3, and a yoke member 4 is fixed on the base 3. Although not shown, a magnet is attached to the yoke member 4, and the yoke member 4 forms a closed loop with a first coil 5 and a second coil 6 provided below the deflection mirror 1. It constitutes a magnetic circuit.

The support member 2 is generally formed of a plate-like spring, and is generally arranged on the rotation axis of the deflecting mirror 1. Then, by passing a current through the first coil 5 and the second coil 6, the deflecting mirror 1 rotates around the central axis 2A of the support member 2 as shown by an arrow A, and the luminous flux applied to the deflecting mirror 1 Can be deflected.

However, in such a galvanomirror device, since the support member 2 is formed of a plate-shaped spring as described above, if the mechanical frequency characteristics are to be further improved, the support member 2 is inevitably used. Becomes longer in the axial direction, which is a major obstacle in reducing the size of the entire apparatus.

Therefore, a galvanomirror device having a configuration as shown in FIGS. 1 and 2 has been proposed. FIG. 1 is an external perspective view of the entire galvano mirror device, and FIG. 2 is an exploded perspective view of the internal configuration. In FIG. 2, the frame of the apparatus main body is omitted. FIG. 3 is a cross-sectional view of the galvano mirror device in a plane including the center line of the mirror holder and perpendicular to the deflection mirror.

The galvanomirror device comprises a deflecting mirror 1
1 is configured to rotatably support a mirror holder 10 having a pivot support system 1. That is, the upper and lower portions of the mirror holder 10 are provided with the bearing portions 12 and 13.
Are provided, and these bearing portions 12 and 13 have conical concave surfaces 12A and 13A. Then, the shaft portion 1 in which the vicinity of the tip abuts near the top of the conical concave surfaces 12A and 13A.
4, 15 are provided. The shaft portion 14 is provided so as to pass through a hole 16A formed in the bush 16, is movable vertically in the hole 16A, and the shaft portion 15 is fixed to a frame 17 of the apparatus main body. In FIG. 2, 18, 1
Reference numeral 9 denotes a flat coil, and reference numerals 20 and 21 denote permanent magnets arranged to face the flat coils 18 and 19.

[0007]

By the way, in a galvanomirror device of a pivot support type, a mirror holder 10 is provided.
As shown in FIG. 3, a preload is applied to the shaft portion 14 in the direction of the arrow in order to make the rotation of the shaft smooth. This preload is applied by a leaf spring 22.

However, if a preload is applied to the shaft 14, there is a disadvantage that the posture of the shaft 14 cannot be normally maintained. That is, the shaft portion 14 is
Usually, the outside diameter of the hole 1 is
6A is formed slightly smaller than the inner diameter, and a gap is formed between the hole 16A and the shaft portion 14. The upper surface of the shaft portion 14 is formed in a spherical shape.

With such a configuration, when a preload is applied from the leaf spring 22, the shaft portion 14 is inclined as shown in FIG. If the tilt direction is constant, there is not much problem. However, the tilt direction is not constant, such as tilting to the left as shown by the solid line in FIG. 4 or tilting to the right as shown by the two-dot chain line. If the direction of inclination of the shaft portion 14 is not constant, the attitude of the deflecting mirror 11 is not constant, and the direction of the light beam irradiated on the deflecting mirror 11 cannot be deflected in an accurate direction.

An object of the present invention is to provide a galvanomirror device which can maintain the direction of reflection of a light beam with high precision by preventing a shaft portion from tilting when a deflection mirror is supported by a pivot support method. It is in.

[0011]

In order to achieve the above object, according to the first aspect of the present invention, there is provided a deflecting mirror, coils provided on both right and left ends of the deflecting mirror, A magnet disposed on the upper and lower ends of the deflecting mirror, the supporter rotatably supporting the deflecting mirror, and rotating the deflecting mirror by passing an electric current through the coil; In the galvanomirror device for deflecting the direction of the light beam irradiated to the mirror, the support portion includes a pair of bearing portions having a conical concave surface, and a pair of shafts having a spherical portion at the tip contacting near the top of the conical concave surface. And the pair of bearings are provided at both upper and lower ends of the deflecting mirror, and one of the pair of shafts is fixed to a frame of the galvanomirror device main body,
The other shaft portion is provided on the frame so as to be movable in the axial direction, and the other shaft portion is coupled to a leaf spring that biases the shaft portion toward the bearing portion. I have.

According to the above configuration, since the shaft is connected to the leaf spring, the posture of the shaft is always constant, and the shaft does not tilt even when a preload is applied from the leaf spring. As a result, it is possible to maintain the posture of the deflecting mirror in a normal state.

As a method for connecting the shaft portion to the leaf spring, a mechanical connecting means as described in claim 2 or an adhesive as described in claim 3 can be used.
Further, one or a plurality of leaf springs can be provided in parallel with the urging direction. If a plurality of the leaf springs are provided in parallel, the rigidity of the leaf spring can be increased as compared with the case of a single leaf spring.

[0014]

Embodiments of the present invention will be described below. (Embodiment 1) FIG. 5 shows a cross section of a galvanomirror device according to the present invention, and is a view corresponding to FIG. 3 described above. In FIG. 5, bearing portions 12 and 13 are fixed to the upper and lower portions of the mirror holder 10, respectively. Bearing part 12,
Reference numerals 13 are arranged such that their central axes are on the same straight line.

The bearing portion 12 has a conical concave surface 12A as shown in an enlarged view in FIG. 6, and the vicinity of the top of the conical concave surface 12A is in contact with the vicinity of the tip of the shaft portion 140. The bearing 13 has a conical concave surface 13A, and the conical concave surface 1A is provided.
The vicinity of the tip of the shaft 15 is in contact with the vicinity of the top of 3A.
The shaft 15 is the same as that shown in FIG.

The shaft 140 has a tapered surface 140A, and a spherical portion 140B is provided at the tip of the tapered surface 140A. Further, the upper surface of the shaft portion 140 is formed in a planar shape, and a circular convex portion 140C is provided at a central portion thereof. Although not shown in an enlarged view, the shaft portion 15 also has a tapered surface, and a spherical portion is provided at the tip of the tapered surface. The shaft 15 is fixed to a lower portion of the frame 17 of the apparatus main body.

A hole 17A is formed in the upper part of the frame 17, and a bush 16 is fitted into the hole 17A.
A hole 16A is formed in the center of the bush 16, and a shaft 140 is inserted into the hole 16A. Hole 16A
Is formed slightly larger than the outer diameter of the shaft 140, and a gap is formed between the hole 16A and the shaft 140. As a result, the shaft 140 moves along the axial direction of the hole 1.
It is movable inside 6A.

A leaf spring 22 is provided above the frame 17. One end of the leaf spring 22 is fixed to the frame 17 by a screw 23, and the other end is connected to the upper surface of the shaft 140. FIG. 7 shows a plan view of the leaf spring 22. The leaf spring 22 has through holes 22A and 22B at both ends thereof, the circular convex portion 140C of the shaft 140 is fitted into the through hole 22A, and the screw 23 is inserted into the through hole 22B.
The circular convex portion 140C of the shaft portion 140 is formed in the through hole 22A.
The shaft 140 and the leaf spring 22 are connected by fitting.

The shafts 140 and 15 are arranged so that their respective central axes are on the same straight line. The tip of the shaft 140 is on the conical concave surface 12A of the bearing 12, and the tip of the shaft 15 is on the bearing. The mirror holder 10 is rotatably supported by the frame body 17 by abutting on the 13 conical concave surfaces 13A. At this time, the shaft 140, the bearing 12,
The bearing portion 13 and the shaft portion 15 are arranged substantially on a straight line.

In the above configuration, when a current flows through the flat coils 18 and 19 shown in FIG. 2, the mirror holder 10 is rotated by the action of electromagnetic induction between the permanent magnets 20 and 21. Thereby, the direction of the light beam irradiated on the deflection mirror 11 can be deflected.

Further, in the galvanomirror device having the above configuration, the shaft 140 is coupled to the leaf spring 22, so that the posture of the shaft 140 is always constant. That is, the leaf spring 2
The shaft 140 is slightly tilted by the change of the position 2 (that is, the preload), but the gap between the shaft 140 and the bush 16 restricts the shaft 140 from being tilted in a desired direction. The posture of 140 is always constant. Therefore, the posture of the mirror holder 10 can be maintained in a normal state, and the direction of the light beam applied to the deflecting mirror 11 can always be deflected in an accurate direction.

(Embodiment 2) FIG. 8 is a sectional view of a galvano mirror device according to Embodiment 2. In the present embodiment, 2
The leaf springs 22 ′ and 22 ″ are provided.
2 'is the same as that shown in FIG.
Is a little different. That is, FIG.
No hole corresponding to the through hole 22A is formed.

A shaft portion 14 is provided between the leaf springs 22 'and 22 ".
A spacer 24 is provided on the 0 side, and a spacer 25 is provided on the screw 23 side. Spacers 24, 2
5 are set to be approximately the same, and the spacers 24, 2
The leaf springs 22 ', 22 "sandwiching 5 are arranged in parallel at a predetermined interval. The spacers 24, 25 are fixed to the leaf springs 22', 22" by an adhesive or the like. And
In order to couple the leaf springs 22 'and 22 "to the shaft portion 140, the circular convex portion 140C of the shaft portion 140 is fitted into a through hole (a through hole corresponding to 22A in FIG. 7) of the leaf spring 22'. Let it.

According to the present embodiment, since the two leaf springs 22 'and 22 "are coupled to the shaft 140, the posture of the shaft 140 is always constant, as in the first embodiment.

Further, according to the present embodiment, two
Since the leaf springs 22 'and 22 "are provided in the urging direction, the rigidity of the leaf spring can be increased as compared with the case of one leaf spring. The number of leaf springs is three or more. (Embodiment 3)

FIG. 9 is a sectional view of a galvanomirror device according to the third embodiment. In the present embodiment, the shaft 14 and the leaf spring 22 are joined by the adhesive 26. Since this shaft portion 14 is the same as that shown in FIG. 3, the upper surface is formed in a spherical shape. The leaf spring 22 is also the same as that shown in FIG. In the figure, the leaf spring 22 is set so as to rise leftward when it comes into contact with the shaft 14.
And a slight gap is secured between the leaf spring 22 and the upper surface of the shaft portion 14. The adhesive 26 is injected into this gap. Further, the leaf spring 22 shown in FIG. 7 can be used. In this case, the through-hole 22A formed in the leaf spring 22 can be used as an injection hole for injecting the adhesive 26.

According to the present embodiment, the leaf spring 2 is
2 are connected, the attitude of the shaft portion 14 is always constant, as in the first and second embodiments.

[0028]

As described above, according to the present invention,
Since the shaft is connected to the leaf spring, the posture of the shaft can be kept constant. As a result, the orientation of the deflecting mirror is maintained in a normal state, and the reflection direction of the light beam can be maintained with high accuracy.

[Brief description of the drawings]

FIG. 1 is an external perspective view of a galvanomirror device of a pivot support type.

FIG. 2 is an exploded perspective view of the internal configuration of the galvanomirror device of FIG.

FIG. 3 is a sectional view of a main part of the galvanomirror device of FIG. 1;

FIG. 4 is a diagram illustrating that a shaft portion is inclined by a preload.

FIG. 5 is a sectional view of a main part of the galvano mirror device according to the first embodiment of the present invention.

FIG. 6 is an enlarged view of a shaft portion and a bearing portion.

FIG. 7 is an enlarged plan view of a leaf spring.

FIG. 8 is a sectional view of a main part of a galvanomirror device according to a second embodiment of the present invention.

FIG. 9 is a sectional view of a main part of a galvanomirror device according to a third embodiment of the present invention.

FIG. 10 is an external perspective view of a conventional galvanometer mirror device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Mirror holder 11 Deflection mirror 12, 13 Bearing part 12A, 13A Conical concave surface 14, 15, 140 Shaft part 16 Bush 17 Frame body 18, 19 Flat coil 20, 21 Permanent magnet 22, 22 ', 22 "Leaf spring 24, 25 Spacer 26 Adhesive

Claims (4)

[Claims] 1. A deflecting mirror, coils provided at both left and right ends of the deflecting mirror, magnets arranged opposite to the coil, and a deflecting mirror provided at both upper and lower ends of the deflecting mirror are rotated. A supporting portion for freely supporting, and turning the deflecting mirror by flowing a current through the coil,
In the galvanomirror device for deflecting the direction of a light beam applied to the deflecting mirror, the support portion has a pair of bearing portions having a conical concave surface, and a spherical portion at the tip abuts near the top of the conical concave surface. A pair of shafts, the pair of bearings are provided at both upper and lower ends of the deflecting mirror, and one of the pair of shafts is fixed to a frame of the galvanomirror device main body; The other shaft portion is provided on the frame so as to be movable in the axial direction, and the other shaft portion is coupled to a leaf spring that biases the shaft portion toward the bearing portion. Galvanometer mirror device. 2. The galvanomirror device according to claim 1, wherein said other shaft portion and said leaf spring are coupled by mechanical coupling means. 3. The galvanomirror device according to claim 1, wherein the other shaft portion and the leaf spring are connected by an adhesive. 4. The galvanomirror device according to claim 1, wherein one or a plurality of said leaf springs are provided in parallel with a biasing direction.