JP2011096301A - Optical pickup - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To stably and reliably press a GRT holder using a press spring. <P>SOLUTION: At the center of an LD receiver 10 of a slide base 1 that is slidable in the radial direction of an optical pickup, a recess 12 is formed around a projection hole 11. In the rear end face 12a of the recess 12, a circular GRT fitting hole 13 is formed around the projection hole 11. On both side surfaces of the recess 12, a pair of stoppers 15 are integrally projected. The press spring 16 has a square body 16a, which is bent substantially in a chevron shape with respect to the mountain fold line S at the center. A pair of protrusions 20 for narrowing the movable range of the press spring 16 in the opening 12A of the recess 12 are integrally projected on the rear end face 12a of the recess 12 while facing the stoppers 15. The press spring 16 is inserted into the recess 12 from the opening 12A, so that the press spring 16 is elastically displaced to elastically press the mountain fold line S onto the end face 9b of the GRT holder 9 in the GRT fitting hole 13. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

The present invention relates to an optical pickup of a disk device such as a Blu-ray Disc recorder (or player), for example, and in particular, a GRT holder can be stably and surely pressed by a pressing spring.

An example of an optical pickup is shown in the schematic diagram of FIG. 7, which is a Blu-ray.
For a disc-type recorder (or player), an engaging portion 1a projecting from an optical disc-facing surface of the slide base 1 is slidably engaged with the guide rail 2 so that the slide base 1 can be slid. The BD optical system 3 and the DVD-CD optical system 4 are provided on the slide base 1, and the BD optical system 3 is a BD laser diode. It has a BD / LD, a diffraction grating GRT, a polarizing beam splitter PBS, a collimator lens CL reciprocated by the spherical aberration correction mechanism 5, a reading light receiving element PD1, and the like. The DVD-CD optical system 4 is a DVD-CD laser. It has a diode DVD-CD / LD, a half mirror HM, a light receiving element PD2 for reading, etc., and is driven by an actuator 6. Objective lens OL is provided, and a control board 7 made of a printed wiring board is locked to the optical disk facing surface of the slide base 1, and each laser diode DVD- is connected to the control board 7 via a flexible flat cable (not shown). CD / LD, B
The D / LD and the light receiving elements PD1 and PD2 for reading are connected.

The reading procedure of the BD optical system 3 will be described. A BD type optical disc in which the laser light a1 from the BD laser diode BD / LD is rotated at high speed through the diffraction grating GRT, the polarization beam splitter PBS, the collimator lens CL, and the objective lens OL. The reflected light b1 is received by the reading light receiving element PD1, and the information recorded on the BD type optical disk is read.

The reading procedure of the DVD-CD optical system 4 will be explained. Laser diode DV for DVD-CD
The laser light a2 is projected from the D-CD / LD through the half mirror HM and the objective lens OL onto the DVD-CD type optical disk rotating at high speed, and the reflected light b2 is read as the light receiving element PD2 for reading.
Is received and the information recorded on the DVD-CD type optical disk is read.

Conventionally, there is an optical pickup shown in FIGS. 8 to 10, in which FIG. 8 is an exploded perspective view of the main part, FIG. 9A is a partially cutaway plan view of the main part, and FIG. ) Is a front view of the main part, FIG.
(C) is a longitudinal sectional view of the main part, and FIG. 10 is a longitudinal sectional view showing the effect of the main part.

As shown in FIGS. 8 and 9, the diffraction grating GRT is disposed in a disc-shaped GRT holder 9, and an operation recess 9 a is formed on the outer peripheral surface of the GRT holder 9.

As shown in FIGS. 8 and 9, a laser diode BD for BD is formed on the rear end surface of the slide base 1.
An LD seat 10 for positioning and fixing the LD is formed, and a projection hole 11 for projecting the laser beam a1 is formed at the center of the LD seat 10, and the LD receiver 10 is centered on the projection hole 11. A rectangular recess 12 is formed at the center of the seat 10, and a circular GRT insertion hole 13 for inserting the GRT holder 9 around the projection hole 11 is formed at the back end surface 12 a of the recess 12.
An operation groove 14 is formed through the top of the T insertion hole 13.

A pair of left and right stoppers 15 are integrally projected on both inner side surfaces of the recess 12.
An opening 12A for inserting the holding spring 16 is formed between the recess 12 and the back end surface 12a of the recess 12, a narrow groove 17 is formed on the bottom surface of the recess 12, and each stopper 15 facing the back end 12a of the recess 12 is formed. The back surface 15a and the back surface 17a of the narrow groove 17 are formed to be flush with each other.

The holding spring 16 is made of an elastically displaceable metal leaf spring having a thickness t of, for example, 0.1 mm, and has a square-shaped main body 16a having a through hole 18 formed in the center thereof. Is bent in a substantially square shape with reference to the central mountain fold line S.

A pair of end plates 16b, 16 that bend in the vertical direction from both ends of the square-shaped main body 16a.
c is integrally formed, and one end plate 16b is formed so that it can be inserted into the narrow groove 17, and both end portions of the other end plate 16c are opposed to the stoppers 15 on the left and right sides of the square-shaped main body 16a. A horizontal plate 16d that protrudes and projects integrally with the end edge of the other end plate 16c is bent at a right angle in the direction opposite to the mountain fold line S.

The procedure for positioning and fixing the diffraction grating GRT will be described. The GRT holder 9 is inserted into the GRT insertion hole 13.
The operating recess 9a of the GRT holder 9 is opposed to the operating groove 14, and the holding spring 1
6 is inserted into the recess 12 through the opening 12A, and one end plate 16b of the holding spring 16 is inserted into the narrow groove 17 to contact the back surface 17a of the narrow groove 17, and the other end plate 16c is The back surface 15 a of the stopper 15 is contacted, and the mountain fold line S of the pressing spring 16 is opposed to the center of the end surface 9 b of the GRT holder 9.

Here, the bending width h1 from the both end plates 16b, 16c of the holding spring 16 to the mountain fold line S is shown.
Is set slightly larger than the gap width h2 of the opening 12A of the recess 12 (h1> h2).
Then, the pressing spring 16 is elastically displaced so that the mountain fold line S is elastically pressed against the center of the end surface 9b of the GRT holder 9 so that the GRT holder 9 is not rotated unexpectedly.

Subsequently, by operating an operation shaft (not shown) inserted into the operation recess 9a of the GRT holder 9 from the operation groove 14, and rotating the GRT holder 9 forward and backward around its axis, the diffraction grating G
Fine adjustment is made so that the laser light a1 passing through the RT is dispersed as desired.

Thereafter, an ultraviolet curable adhesive is filled from the operation groove 14 into the operation recess 9a of the GRT holder 9 by an adhesive filling device (not shown), and the ultraviolet curable adhesive is irradiated to cure the ultraviolet curable adhesive. Thus, the GRT holder 9 is fixed to the slide base 1. In addition, there exists what was described in patent document 1 as a related technique.

JP 2007-242203 A

In the above conventional configuration, as shown in the enlarged view of FIG. 9C, the gap width h2 of the opening 2A of the recess 12 is much larger than the thickness t of the pressing spring 16, and the pressing in the opening 12A. Since the movable range K of the spring 16 is relatively large, the pressing spring 16 may be strongly pressed and deformed when inserted into the recess 12 from the opening 12A (see the phantom line in the enlarged view).
Thereby, the bending width h1 of the holding spring 16 is reduced, and as shown in FIG.
Even if the mountain-fold line S of the presser spring 16 is separated from the end surface 9b of the GRT holder 9 to form the gap α or the gap is not generated, the pressing force by the presser spring 16 is reduced, and the GRT holder 9 by the presser spring 16 is reduced. There is a possibility that the pressing of the GRT holder 9 becomes unstable, and the GRT holder 9 is rotated unexpectedly, and the fine adjustment state of the diffraction grating is distorted.

Moreover, a finger part contacts the horizontal plate 16d of the holding spring 16 inserted into the recessed part 12, etc.,
There is a risk that the presser spring 16 is inclined or displaced in the direction of coming out of the recess 12. In this case, the mountain fold line S of the presser spring 16 deviates from the position facing the center of the end surface 9b of the GRT holder 9, and the GRT The holder 9 cannot be securely pressed.

An object of the present invention is to provide an optical pickup capable of stably and surely pressing a GRT holder by a pressing spring in view of the above-mentioned conventional drawbacks.

In order to achieve the above object, according to the first aspect of the present invention, a projection hole is formed in the center of a slide base LD seat slidable in the radial direction of the optical pickup, and the LD seat is centered on the projection hole. A recess is formed in the center of the circular GRT centering on the projection hole at the back end surface of the recess
A fitting hole is formed, a pair of stoppers are integrally provided on both side surfaces of the recess, an opening for inserting a presser spring is formed between the stoppers and the back end surface of the recess, and the presser spring is A B-shaped main body having a through-hole formed in the center thereof, and the B-shaped main body is bent into a substantially square shape with reference to a central mountain fold line, and the GRT holder is inserted into the GRT insertion hole. Insert
Insert the holding spring into the recess from the opening, elastically displace the holding spring,
The laser light is elastically pressed against the end face of the RT holder, and laser light is projected from the laser diode fixed to the LD seat through the diffraction grating held by the GRT holder 9 onto the optical disk, and recorded on the optical disk based on the reflected light. In an optical pickup that reads the information
It has the movable range control part which narrows the movable range of the presser spring in the opening part of the said recessed part, It is characterized by the above-mentioned.

The invention according to claim 2 is characterized in that, in the invention according to claim 1, the movable range restricting portion is formed of a protruding portion that is integrally provided on the back end surface of the recess and approaches each stopper. .

According to a third aspect of the present invention, in the first aspect of the present invention, the movable range restricting portion is formed of a bent piece that is bent from the pressing spring and approaches the back end surface of the concave portion.

The invention according to claim 4 is the invention according to claim 2 or 3, wherein a positioning hole is formed through the bottom surface of the recess, and the back surface of each stopper facing the back end surface of the recess and the back surface of the positioning hole Is formed in a flush manner, an insertion plate inserted into the positioning hole is integrally projected on the holding spring, a retaining hole is formed through the insertion plate, and a retaining projection that can be fitted to the retaining hole is a positioning hole. It is characterized in that it is integrally projected on the back surface.

According to the first aspect of the present invention, when the pressing spring is inserted into the recess from the opening, the movable range of the pressing spring is reduced by the movable range restricting portion to restrict the pressing spring from being deformed. Therefore, the difficulty that the holding spring is pressed strongly and the bending width is reduced as in the prior art is eliminated, and the end face of the GRT holder can be stably pressed by the mountain fold line of the holding spring. It is possible to prevent the unexpected rotation and reliably maintain the fine adjustment state of the diffraction grating.

According to invention of Claim 2, since the projection part is integrally formed in the slide base,
The number of parts does not increase and it is economical.

According to the invention of claim 3, since the bent piece is integrally formed with the holding spring,
The number of parts does not increase and it is economical.

According to the fourth aspect of the present invention, the insertion plate is inserted into the positioning hole by inserting the holding spring into the recess from the opening, and the retaining hole of the insertion plate is fitted to the retaining projection, Since the spring is locked at a predetermined position in the recess, the finger spring comes into contact with the presser spring inserted into the recess as in the conventional case, and the presser spring is tilted or displaced in the direction of coming out of the recess. Therefore, the GRT holder can be surely pressed by making the mountain fold line of the holding spring accurately contact the center of the end face of the GRT holder.

It is a disassembled perspective view which shows the principal part of the optical pick-up which is one Embodiment of this invention. It is a perspective view which shows the assembly state of the principal part. (A) is a partially cutaway plan view of the main part, (b) is a front view of the main part, and (c) is a longitudinal sectional view of the main part. It is a disassembled perspective view which shows the principal part of the optical pick-up which is another form of implementation of this invention. It is a perspective view which shows the assembly state of the principal part. (A) is a partially cutaway plan view of the main part, (b) is a front view of the main part, and (c) is a longitudinal sectional view of the main part. It is the schematic which shows an example of an optical pick-up. It is a disassembled perspective view of the principal part which shows a prior art example. (A) is a partially cutaway plan view of the main part, (b) is a front view of the main part, and (c) is a longitudinal sectional view of the main part. It is a longitudinal cross-sectional view which shows the effect of the principal part.

1 to 3 show an essential part of an optical pickup according to an embodiment of the present invention, which is for a Blu-ray Disc recorder (or player), and has an opening 12A of a recess 12. A pair of protrusions (movable range restricting portions) 20 that narrow the movable range K of the presser spring 16 inside are opposed to the stoppers 15 and are integrally projected on the back end surface 12a of the concave portion 12,
A gap β slightly larger than the thickness t of the presser spring 16 is formed between each projection 20 and each stopper 15.

As shown in FIGS. 1 to 3, a positioning hole 21 is provided through the bottom surface of the recess 12, and the back surface 15 a of each stopper 15 facing the back end surface 12 a of the recess 12 and the back surface 21 a of the positioning hole 21 are flush with each other. And an insertion plate 16e inserted into the positioning hole 21 is integrally protruded from one end plate 16b of the presser spring 16, and a retaining hole 23 is formed through the insertion plate 16e so as to be fitted into the retaining hole 23. A possible retaining protrusion 22 is integrally projected on the back surface 21 a of the positioning hole 21. Since the configuration other than the above is substantially the same as the configuration shown in FIGS. 7 to 10, the same reference numerals are given to the same portions and the description thereof is omitted.

The procedure for positioning and fixing the diffraction grating GRT will be described. The GRT holder 9 is inserted into the GRT insertion hole 13.
The operating recess 9a of the GRT holder 9 is opposed to the operating groove 14, and the holding spring 1
6 is inserted into the recess 12 through the gap β between each stopper 15 and each projection 20 of the opening 12A, the insertion plate 16e of the holding spring 16 is inserted into the positioning hole 21, and the retaining hole of the insertion plate 16e is inserted. 23 is fitted to the retaining protrusion 22, and the insertion plate 16 e is brought into contact with the back surface 21 a of the positioning hole 21, and the other end plate 16 c is brought into contact with the back surface 15 a of each stopper 15. S is elastically pressed against the center of the end surface 9b of the GRT holder 9, and the GR
The T holder 9 is prevented from rotating unexpectedly (see FIG. 2). Since the subsequent operations are almost the same as those in the prior art, the description thereof is omitted.

According to the above configuration, the insertion plate 16e is inserted into the positioning hole 21 by being inserted into the recess 12 from the opening 12A of the holding spring 16, and the retaining hole 23 of the insertion plate 16e is fitted to the retaining projection 22. Since the presser spring 16 is locked at a predetermined position in the concave portion 12, the finger portion comes into contact with the horizontal plate 16d of the presser spring 16 inserted into the concave portion 12 as in the prior art.
The presser spring 16 is not tilted or displaced in the direction of coming out of the recess 12, and the mountain fold line S of the presser spring 16 is accurately brought into contact with the center of the end surface 9 b of the GRT holder 9,
The GRT holder 9 can be securely pressed.

Further, when the presser spring 16 is inserted into the recess 12 from the opening 12A, the movable range K of the presser spring 16 is reduced by the two projecting parts 20 to restrict the presser spring 16 from being deformed. The pressing spring 16 is not strongly pressed as in the prior art, and the bending width h1 is not reduced, and the end surface 9b of the GRT holder 9 can be stably pressed by the mountain fold line S of the pressing spring 16. The GRT holder 9 can be prevented from rotating unexpectedly, and the fine adjustment state of the diffraction grating GRT can be reliably maintained.

Furthermore, since the protrusion 20 is integrally formed with the slide base 1, the number of parts does not increase, which is economical.

4-6 shows the principal part of the optical pick-up which is the other form of implementation of this invention,
This is for a Blu-ray Disc type recorder (or player) and has a recess 12
A pair of bent pieces (movable range restricting portions) 25 for narrowing the movable range K of the pressing spring 16 in the opening 12A are integrally formed at both ends of one end plate 16b of the pressing spring 16, and each bent piece 25 is The bent portion S is bent at a right angle in the same direction as the protruding direction of the mountain fold line S and protrudes toward the back end surface 12a of the recess 12, and the protruding width M of each bent piece 25 is the gap width h2 of the opening 12A.
Is set to be slightly smaller. Since the configuration other than the above is substantially the same as that of the embodiment of the present invention shown in FIGS. 1 to 3, the same parts are denoted by the same reference numerals and the description thereof is omitted.

The procedure for positioning and fixing the diffraction grating GRT will be described. The GRT holder 9 is inserted into the GRT insertion hole 13.
The operating recess 9a of the GRT holder 9 is opposed to the operating groove 14, and the holding spring 1
6 is inserted into the recess 12 from the opening 12 </ b> A, and the tip of each bent piece 25 is brought close to the back end surface 12 a of the recess 12. Subsequent operations are substantially the same as those of the embodiment of the present invention shown in FIGS.

According to the above configuration, substantially the same effect as that of the embodiment of the present invention shown in FIGS. 1 to 3 can be obtained. In particular, when the presser spring 16 is inserted into the recess 12 from the opening 12A, it is bent in both directions. Since the movable range K of the presser spring 16 is reduced by the piece 25 to restrict the presser spring 16 from being deformed, the presser spring 16 is strongly pressed as in the prior art, and the bending width h1 is reduced. There is no end face 9b of the GRT holder 9 by the mountain fold line S of the holding spring 16
Thus, the GRT holder 9 can be prevented from rotating unexpectedly, and the fine adjustment state of the diffraction grating GRT can be reliably maintained.

Further, since the bent piece 25 is integrally formed with the presser spring 16, the number of parts does not increase and it is economical.

DESCRIPTION OF SYMBOLS 1 Slide base 9 GRT holder 9b End surface of GRT holder 10 LD seat 11 Projection hole 12 Recessed part 12a Recessed end face 13 GRT insertion hole 15 Stopper 15a Back side of stopper 16 Pressing spring 16a Roller-shaped main body 16e of pressing spring Insertion plate 18 Through-hole in B-shaped body 20 Protruding part (movable range regulating part)
21 Positioning hole 21a Back surface of positioning hole 22 Retaining protrusion 23 Retaining hole 25 Bending piece (movable range restricting portion)
BD / LD BD Laser Diode GRT Diffraction Grating S Mountain Fold Line K Movable Range

Claims (4)

A projection hole is formed in the center of the LD base of the slide base that is slidable in the radial direction of the optical pickup, a recess is formed in the center of the LD base around the projection hole, and projection is performed on the back end surface of the recess. A circular GRT insertion hole is formed with the hole at the center, a pair of stoppers are integrally projected on both side surfaces of the recess, and an opening for inserting a holding spring between the stopper and the back end surface of the recess The holding spring has a square-shaped main body with a through-hole penetrating in the center, and the square-shaped main body is bent in a substantially square shape with reference to the central mountain fold line. , The GRT
From the laser diode fixed in the LD seat, the GRT holder is inserted into the insertion hole, the holding spring is inserted into the recess through the opening, the holding spring is elastically displaced and the fold line is elastically pressed against the end face of the GRT holder. In an optical pickup in which laser light is projected onto an optical disk through a diffraction grating held by a GRT holder 9 and information recorded on the optical disk is read based on the reflected light, a holding spring in the opening of the concave portion An optical pickup comprising a movable range restricting portion that narrows the movable range of the optical pickup. 2. The optical pickup according to claim 1, wherein the movable range restricting portion includes a protruding portion that integrally protrudes from a rear end surface of the concave portion and approaches each stopper. 2. The optical pickup according to claim 1, wherein the movable range restricting portion is formed of a bent piece that is bent from the pressing spring and approaches the back end surface of the concave portion. A positioning hole is formed through the bottom surface of the recess, the back surface of each stopper facing the back end surface of the recess is formed flush with the back surface of the positioning hole, and the insertion plate inserted into the positioning hole serves as a pressing spring. 4 or 3, wherein the insertion plate is provided with a retaining hole, and a retaining protrusion that can be fitted into the retaining hole is integrally projected on the rear surface of the positioning hole. The optical pickup described.

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