JPH08250872A - Mounting part of precision unit - Google Patents

Abstract

PURPOSE: To fix a precision unit to a base without deformation. CONSTITUTION: A plurality of bosses 24 and threaded holes 25 are formed on a head base 20, while a fixing head 23 positioned by a positioning pin 26 is mounted. A fixing part 27 formed on the plastically deformable fixing head 23 so that even the boss 24 on the base 20 is tilted, the fixing part 27 elastically deforms by pressing force of a screw 30 at the time of fixing and fixed according to the face of the boss 24.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mounting portion for a precision unit such as an optical unit incorporated in an optical information recording / reproducing apparatus for recording / reproducing information by irradiating a light beam. Is.

[0002]

2. Description of the Related Art Conventionally, various types of media such as a disk, a card, and a tape have been known as a form of a medium for recording information or reading the recorded information using light. These optical information recording media include those that can be recorded and played back, those that can only be played back, etc. In particular, optical cards as recording media are easy to manufacture, have good morphology, and have good accessibility. It is considered that the applications will be expanded due to such features. Various devices are provided for recording / reproducing optical information for the optical card.

In such an optical information recording / reproducing apparatus,
Recording and reproduction are performed while always performing auto-tracking control and auto-focusing control. Recording of information on a recording medium is performed by operating an information track with a light beam that is modulated according to the recording information and focused into a minute spot, and information is recorded as an optically detectable information pit string. It The reproduction of information from the recording medium is performed by scanning the information pit row of the information track with a light beam spot having a constant power such that recording is not performed on the medium and detecting reflected light or transmitted light from the medium. .

FIG. 13 is a perspective view showing the structure of an integrated optical head of a conventional optical information recording / reproducing apparatus for an optical card. On the front optical path of the light source 1 such as a semiconductor laser, a collimator lens 2 for converting a light beam into parallel light, a prism 3 for converting the cross-sectional distribution of the light beam from an elliptical shape into a circle, and a diffraction grating 4 for dividing the light beam into three beams. , The beam splitter 5, the mirror 6, and the objective lens 7 are sequentially arranged, and the optical card C is arranged in front of the objective lens 7. A condenser lens system 8 and photodetectors 9a, 9b, 9c are arranged in the reflecting direction of the beam splitter 5, and the photodetector 9b has a light-receiving surface divided into four.

The laser beam emitted from the light source 1 is collimated by the collimator lens 2, passes through the prism 3, and is divided into three beams by the diffraction grating 4. These light beams pass through the beam splitter 5, are reflected by the mirror 6, and are tracked by the objective lens 7 on the optical card C such as the tracking track T1, the information track T2, and the tracking track T3.
To form beam spots S1, S2, and S3, respectively.

Here, the optical card C is moved in the direction of arrow R by a driving means (not shown), and the beam spots S1, S2,
By S3, the track is scanned in the extending direction. The reflected light of the beam spots S1, S2, S3 again passes through the objective lens 7, is reflected by the beam splitter 5, and is projected onto the photodetectors 9a, 9b, 9c via the condenser lens system 8, respectively. The condenser lens system 8 is an astigmatism system and is arranged so that autofocusing can be performed by the astigmatism method.

Although the above description is for the integrated optical head, a separate optical head has recently been proposed in order to reduce the size and weight of the device. FIG. 14 is a side view showing the configuration of the separation type optical head. In order to reduce the weight of the movable part of the optical head, only the part that needs to be moved at least is the movable head part 10 and is separated from the fixed head part 11. are doing. The fixed head portion 11 is fixed to the head base 12 with screws,
Each optical component is adhered or screwed to the fixed head portion 11. The movable head unit 10 is coupled to the head base 12 via a guide rail 13 and scans the optical card C in a direction orthogonal to the arrow.

[0008]

However, in the separation type optical head as in the conventional example shown in FIG. 14 described above, the fixed head portion 11 is directly screwed to the head base 12, so that the fixed head portion 11 is fixed. The pressing force and the inclination of the mounting surface cause the fixed head portion 11 to be distorted, whereby the optical components in the fixed head portion 11 are inclined and the emission optical axis of the laser beam from the light source 1 and the photoelectric detectors 9a and 9a and 9a.
Since the optical axes of b and 9c are displaced, the movable head unit 1
When the light emitted to 0 is reflected by the optical card C and enters the photoelectric detectors 9a, 9b, 9c of the fixed head portion 11, there arises a problem that the photoelectric detectors 9a, 9b, 9c are deviated from the centers.

The object of the present invention is to solve the above problems,
An object of the present invention is to provide a mounting portion for a precision unit portion such as a fixed head portion that does not cause distortion at the time of fixing the precision unit portion when fixing the precision unit portion on a base.

[0010]

The mounting portion of the precision unit portion according to the first aspect of the invention for achieving the above object is to mount the precision unit portion on the base when the precision unit portion is mounted on the base. At least one of the fixing members to be fixed has a structure that causes plastic deformation during fixing.

The mounting portion of the precision unit portion according to the second aspect of the invention is such that when the precision unit portion is mounted on the base by interposing an intermediary member between the base and the precision unit portion, the base or / Also, at least one of the fixing members for fixing the precision unit portion and the intermediary member has a structure that causes plastic deformation during fixing.

[0012]

The mounting portion of the precision unit portion of the first invention having the above-described structure has a structure in which at least one of the fixing members for the base and the precision unit portion undergoes plastic deformation when being fixed so that the precision unit portion is not distorted. Fix it to the base so that it does not occur.

In the mounting portion of the precision unit portion of the second invention, an intermediary member is interposed between the base and the precision unit portion, and at least one of a fixing member for fixing the base or / and the precision unit portion and the intermediary member. Is fixed to the base so that the precision unit does not become distorted.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail with reference to the embodiments shown in FIGS. 1 is a plan view showing a separation type optical head of the first embodiment, FIG. 2 is a sectional view taken along the line AA of FIG. 1 showing a mounting state of a fixed head portion and a head base, and FIG.
FIG. 3 is a plan view seen from the direction C in FIG. 2.

A guide rail 21 is provided on the head base 20.
a and 21b are fixed, and the movable head portion 22 is attached to the guide rails 21a and 21b. The movable head portion 22 can be scanned along the guide rails 21a and 21b in the arrow B direction by a linear motor or the like (not shown). ing. A fixed head portion 23 is attached in the extension line direction of the guide rails 21a and 21b. Head base 20
A plurality of boss portions 24 and tap holes 25 are formed in the fixed head portion 23, and the fixed head portion 23 positioned by the positioning pin 26 is attached via a tongue-shaped fixed portion 27.

The fixing portion 27 formed on the fixed head portion 23 has a plastic property in the hole portion 29 of the protruding portion 28 laterally extended from the fixed head portion 23 as shown in FIGS. The tap hole 25 of the screw 30 is provided as a deformable member.
It is fixed to the boss portion 24 of the head base 20 by screwing.

Therefore, even when the fixing portion 27 is inclined as shown in FIG. 2, the fixing portion 27 is plastically deformed at the root portion by the pressing force of the screw 30 during fixing, and the head base 2
It is attached following the surface of the 0 boss portion 24. Therefore, no distortion is generated inside the fixed head portion 23,
The entire fixed head portion 23 does not tilt. In addition, for example, a boss portion may be formed on the back surface of the fixed head portion 23, and a member that is plastically deformed may be provided on the head base 20 side.

FIG. 4 shows an embodiment in which the shape of the fixed portion 27 of the fixed head portion 23 is changed, and the fixed portion 27 is hung over the hole 29 of the overhanging portion 28 in a plastically deformable manner. The same operation and effect as in the case of.

FIG. 5 is a side view of the second embodiment, FIG. 6 is a plan view, and the same reference numerals as those in the first embodiment indicate the same members. An intermediate member 31 is provided between the head base 20 and the fixed head portion 23, a boss portion 24 is formed on the head base 20, and a boss portion 32 is formed on the fixed head portion 23. Is interposed between the boss portion 24 and the boss portion 32. In addition, 33 is a mirror of the movable head unit 22, 34 is an objective lens, and C is an optical card.

FIG. 7 and FIG. 8 are lines EE and F of FIG. 6, respectively.
FIG. 9 is a cross-sectional view showing a fixed state along the line −F, FIG. 9 is a plan view seen from the direction D of FIG. 7, cuts 35 are provided in the intermediary member 31, and the boss portion 2 is provided between the cuts 35.
A fixing portion 36 which is plastically deformable with respect to 4 and 32 is provided, and the intermediary member 31 is fixed to the boss portion 24 of the head base 20 and the boss portion 32 of the fixed head portion 23 with screws 30 via the fixing portion 36, respectively. Has been done. At this time, the flatness of the intermediate member 31 is maintained even if the fixing portions 36 of the intermediate member 31 are plastically deformed and the boss portions 24 and 32 are inclined, and the head base 20 and the fixed head portion 23 are It is fixed accurately without distortion.

FIG. 10 shows a modification of the intermediary member 31, in which four slits 38 are provided around the screw hole 37 so that the fixing portion 39 of the intermediary member 31 can be deformed.

FIG. 11 is a perspective view of another modified example of the intermediary member 31, and FIG. 12 is a sectional view thereof. The fixing portion 40 around the screw hole 37 is thin, and the boss portion 24 of the base 20 is shown. It is said that it can be transformed in accordance with.

Although the above description has been made with respect to the mounting portion of the separate type optical head, when fixing the precision unit portion on the head base 20, a fixing force acts to cause distortion inside the precision unit portion. In the case where it does not occur, it is sufficient to use the mounting portion as described above, and the precision unit portion can be applied to other than the separation type optical head.

[0024]

As described above, the mounting portion of the precision unit portion according to the present invention has a structure in which the fixed portion between the base and the precision unit portion undergoes plastic deformation, so that the precision unit portion is distorted inside. The precision unit can be fixed to the base without causing

[Brief description of drawings]

FIG. 1 is a plan view of a first embodiment.

FIG. 2 is a sectional view taken along the line AA.

FIG. 3 is a plan view seen from the direction C.

FIG. 4 is a plan view of another embodiment of the fixing portion.

FIG. 5 is a side view of the second embodiment.

FIG. 6 is a plan view.

FIG. 7 is an enlarged cross-sectional view taken along the line EE of FIG.

FIG. 8 is an enlarged cross-sectional view taken along the line FF of FIG.

FIG. 9 is a plan view seen from the D direction.

FIG. 10 is a perspective view of another embodiment of the fixing portion.

FIG. 11 is a perspective view of another embodiment of the fixing portion.

FIG. 12 is a sectional view.

FIG. 13 is a perspective view of a conventional integrated optical head.

FIG. 14 is a side view of the separated optical head.

[Explanation of symbols]

 20 Head Base 22 Movable Head Part 24, 32 Boss Part 23 Fixed Head Part 27, 36, 39, 40 Fixed Part 31 Mediation Member

Claims (2)

[Claims] 1. When attaching a precision unit section to a base, at least one of the fixing members for fixing the base and the precision unit section has a structure that causes plastic deformation during fixing. The mounting part of the precision unit. 2. When the precision unit section is attached to the base by interposing an intermediary member between the base and the precision unit section, the base or / and the precision unit section and the intermediary member are provided. A mounting unit for a precision unit, wherein at least one of the fixing members to be fixed has a structure that causes plastic deformation during fixing.