JPH05107433A - Method of aligning axis of optical part and aligning mechanism - Google Patents

Abstract

PURPOSE:To provide a mirror frame mechanism which has a high degree of accuracy with respect to the optical axis of a shaft member fixed to the mirror frame, which does not require to enhance the machining accuracy, and which can reduce the cost of the part and as well as can reduce the manhours for assembly. CONSTITUTION:A positioning jig 4 for a guide rod is fitted in a mirror frame 1, and shaft members 2, 3 are fitted in fitting holes 4a for holding the shaft members 2, 3 in parallel with the optical axis O. Then, the shaft members 2, 3 are inserted in loosely fitting holes 1a in the moor fame 1, and then adhesive 5 is filled in gaps in the loosely fitting holes 1a so that the mirror frame 1 and the shaft members 2, 3 are bonded so as to be secured in parallel with the optical axis O.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of aligning an optical component and an axis aligning mechanism, and more particularly, to a part of a lens barrel, which comprises The present invention relates to a fixing method and a mechanism with respect to a shaft member that supports another lens frame and the like.

[0002]

2. Description of the Related Art In recent years, in a zoom lens or the like, a guide rod having two shaft members instead of a cylindrical frame for linearly guiding a mirror frame for the purpose of downsizing, weight reduction, and high precision. , And a mechanism for moving the lens frame of each lens group forward and backward is adopted. In this mechanism, first,
The above two guide bars are relative to the optical axis of the reference lens frame.
It is necessary to fix them in parallel and symmetrically.

Conventionally, as a method of fixing the guide rod, a press-fitting method, a screwing method, an insert molding method, an abutting method and the like have been adopted. In the press-fitting method, as shown in FIG. 6, two fitting holes 5 are provided in the lens frame 51 in parallel with the optical axis O thereof.
1a is provided, and the guide rods 52 and 53 are press-fitted and fixed in the fitting hole 51a. Further, in the screwing method, as shown in FIG. 7, the lens frame 61 is provided with two screw holes 61a provided parallel to the optical axis O thereof, and the guide rod 6 is provided in the screw holes 61a.
This is a method of screwing and fixing 2, 63. The insert molding method is a method in which the guide rods 72 and 73 are fixed and fixed by insert molding when the lens frame 71 is molded as shown in FIG. Further, the fitting method is as shown in FIG.
As shown in (B) of FIG.
Guide rods 82 and 83 are attached to a groove 81a having two V-shaped abutment surfaces provided in parallel with the optical axis O, and the L-shaped fixing plate 84 is fixed to the lens frame 81 with a screw 85. This is a method of fixing the guide rods 82 and 83 to the lens frame 81.

[0004]

However, according to the above-mentioned conventional fixing methods, the accuracy of fixing the parallelism of the guide rod to the optical axis is not sufficient in any case. That is, in the press-fitting method, it was difficult to obtain the parallel accuracy of the fitting hole 51a, and it was difficult to control the press-fitting dimension accuracy of the hole itself. Further, in the screwing method, the screw hole 61
It is even more difficult to ensure the parallel accuracy of a with respect to the optical axis. In the insert molding method, even if the accuracy on the molding die can be guaranteed, due to internal stress during molding, etc.
The parallelism of the guide rods 72 and 73 may be lost after the mold is released. Further, in the abutting method, not only high accuracy is required for processing the abutting surface, but also the tip of the guide rod may shake due to a change in the abutting force. Further, according to this method, dedicated parts such as a fixing plate are required, and the material cost becomes high.

The present invention has been made to solve the above-mentioned problems, is advantageous in terms of material cost, does not depend on the machining accuracy of the guide rod supporting hole for its fixing accuracy, and An object of the present invention is to provide an axis alignment method and an axis alignment mechanism for an optical component in which distortion of processing or molding does not act on a guide rod.

[0006]

As shown in the conceptual diagram of FIG. 1, an optical axis O of a lens frame 1 forming a part of a lens barrel and an optical axis O of this lens frame are provided. In the method of aligning the optical components, which is fixed at a position deviated from the optical axis O of 1 and is parallel to the axes of the shaft members 2 and 3 which guide the other lens frames in the optical axis direction, On the other hand, the shaft members 2 and 3
Is loosely fitted, the optical axis and the axis of both are made parallel by the jig 4, and then both are fixed by the adhesive 5.

Similarly, as shown in the conceptual diagram of FIG. 1, the axial alignment mechanism of the optical component of the present invention is provided at a position deviated from the optical axis of the lens frame 1 in the axial alignment mechanism of the optical component. And has a loose fitting hole into which the shaft members 2 and 3 are loosely fitted, and a fitting surface 4c into which the lens frame 1 is fitted and when the lens frame 1 is fitted into the fitting surface 4c. A jig 4 having a fitting hole 4a provided at a position overlapping the loose fitting hole 1a, into which the shaft members 2 and 3 are fitted, and the axes of the fitting surface 4c and the fitting hole 4a are parallel to each other. It is characterized in that the lens frame 1 and the shaft members 2 and 3 are fitted and fitted into each other, and the loose fitting state of the lens frame 1 and the shaft members 2 and 3 is fixed by an adhesive 5.

[0008]

Operation: The fitting surface 4c of the jig 4 is fitted into the lens frame 1,
The fitting hole 4a and the loose fitting hole 1a overlap each other. Then, the shaft members 2 and 3 are fitted into the fitting holes 4a of the jig 4, and further inserted into the loose fitting holes 1a of the lens frame 1. Subsequently, the adhesive 5 is injected from the adhesive injection hole 1b provided in the lens frame 1 to fix the shaft members 2 and 3 in the loose fitting hole 1a of the lens frame 1. And
As shown in FIG. 2, shaft members 2 and 3 are fixed to the lens frame 1 in parallel with the optical axis O.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the illustrated embodiments. FIG. 3 is a vertical cross-sectional view of a lens frame mechanism portion that is an axis alignment mechanism assembled based on an axis alignment method for optical components according to an embodiment of the present invention. As shown in this figure, this mechanism portion constitutes a part of the lens barrel, and includes a lens frame 11 for holding an optical member such as a lens and a shaft member for supporting another lens frame. The guide rods 12 and 13 are fixed with an adhesive 15 using a guide rod positioning jig 14. That is, the lens frame 11 is loosely fitted into the guide rods 12 and 13 with a clearance of 0.02 to 0.05 mm in diameter.
A fitting opening portion 11c, etc., into which a and the fitting surface of the fitting portion 14c parallel to the optical axis O of the guide rod positioning jig 14 are fitted with almost no gap, are provided.

An injection port 11b for the adhesive 15 is provided in the loose fitting hole 11a. The loose fitting hole 11
A chamfered portion 11d is provided on both end surfaces of a, and a chamfered portion 11e is also provided on the outer surface side of the injection port 11b. On the other hand, in addition to the fitting portion 14c, the guide rods 12 and 13 can be fitted to the jig 14 with almost no gap, and two guide rod fitting holes 14a having a predetermined interval parallel to the optical axis O are provided. It is provided. The fitting portion 14c of the fitting hole 14a
As shown in the perspective view of FIG. 4, a concave escape portion 1 is provided at the end on the side.
4d is provided. Further, knurled portions 12a and 13a for preventing coming out are provided in portions of the guide rods 12 and 13 to be inserted into the loose fitting holes 11a. Alternatively, the knurled portions 12a and 13a may be used by scratching the shaft outer shape by punching. The opening 11c of the lens frame 11 is a portion for holding an optical member such as a lens.

In assembling the guide rod in the lens frame mechanism portion of the present embodiment configured as described above, first, the fitting portion 14c of the positioning jig 14 is fitted into the fitting opening portion 11c of the lens frame 11. .. Then, the fitting hole 14a of the guide rod and the loose fitting hole 11a are kept in a state where their axes coincide with each other.

Subsequently, the guide rods 12 and 13 are fitted through the fitting holes 14a of the positioning jig 14 to form the knurled portion 1.
2a and 13a are inserted into the loose fitting portion 11a. With the guide rods 12 and 13 held, the adhesive 5 is filled with the adhesive 5.
It is injected from b into the gap of the loosely fitting portion 11a, and the guide rods 12 and 13 are fixed to the lens frame 11. As the adhesive 5, for example, a cyanoacrylic adhesive having a high curing speed, a high adhesive strength, a low curing shrinkage and a high permeability is used. Also,
An epoxy UV (ultraviolet) curable adhesive may be used.

In the adhesive structure of this mechanical portion, since the adhesive injection port 11b has the chamfered portion 11e as described above, it is easy to inject the adhesive. Further, since the injection port 11b is provided in the central portion of the side surface, the adhesive 5 is loosely attached to the loose fitting portion 11a.
Can be spread over the entire gap. Moreover, since the chamfered portions 11d are provided at the upper and lower ends of the loose fitting portion 11a, the adhesive 5 can be prevented from protruding, and a curing accelerator can be applied to the chamfered portions 11d for immediate curing. Is also possible. Further, when the above UV-curable adhesive is used, the chamfered portion 11d can be irradiated with UV for initial curing. In addition, the escape portion 1 of the positioning jig 14
4d can be used as a coating work port of the above-mentioned curing accelerator and a UV irradiation port when a UV-curable adhesive is used. Further, by providing this escape portion 14d, it is possible to prevent the adhesive from adhering to the positioning jig 4.
Further, since the knurled portions 12a and 13a are provided on the bonded portions of the guide rods 12 and 13 as described above, the strength in the pull-out direction can be further improved. Then, the guide rods 12, 1 of the loose fitting portion 11a of the lens frame 11
The gap with 3 is 0.02-0.05 in diameter as described above.
The gap is reduced to about mm to prevent the parallelism from fluctuating due to curing shrinkage of the adhesive. Note that if the gap is smaller than the above-mentioned gap, the accuracy of hole processing affects the accuracy of assembling the guide rod to the lens frame, which is not preferable.

As described above, in the lens frame mechanism portion of the present embodiment, it is not necessary to provide the lens frame 11 with fixing portions such as press-fitting holes and screws for fixing the guide rods 12 and 13 which require high precision. It is only necessary to provide the loose fitting portion 11a that does not need to be highly accurate, and the guide rods 12 and 13 can be accurately fixed to the optical axis O at the position held by the positioning jig 14. This makes it possible to reduce the number of assembling steps and the cost of parts.

In the lens frame mechanism according to the above embodiment, the above lens frame can be used as a reference first lens frame, and other second and third lens frames can be further assembled. FIG. 5 shows the first and
The longitudinal cross-sectional view of the assembled state of a few mirror frames is shown. First above
The lens frame 21 has a loose fitting portion 21a for the guide rods 26 and 27 and an adhesive injection port 21b, and the guide rods 26 and 27 are bonded and fixed to the loose fitting portion 21a in parallel with the optical axis O. ing. The second and third lens frames 22 and 23 are provided with loose fitting holes 28 and 29, respectively, which are loosely fitted to the outer shapes of the sleeves 24 and 25 fitted to the guide rod 26 in a play-free state. Fitting hole 2
Adhesive injection ports 22b and 23b are provided at 8 and 29, respectively. Further, U-shaped grooves 22e and 23, which are guided straight by a guide rod 27, are provided on opposite sides of the loose fitting holes 28 and 29.
e are provided respectively. An optical member such as a lens is attached to the inner peripheral openings 21c, 22c, and 23c of each lens frame.

As shown in FIG. 5, the assembling of the present lens frame mechanism configured as described above is based on the first lens frame 21 to which the guide rods 26 and 27 are adhesively fixed, and the fitting opening 21 thereof.
In addition, the printing basket 22d of the second lens frame 22 is attached to c, and the second lens frame 2
The cage portions 23d of the third lens frame 23 are fitted into the second fitting openings 22c. Then, the sleeves 24, 25
Are inserted into the loose fitting holes 28 and 29 and held parallel to the optical axis O. In this state, cyanoacrylic adhesive 2
8 and 29 are injected from the adhesive injection ports 22b and 23b of the sleeves, and the sleeves 24 and 25 are adhesively fixed to the lens frames 22 and 23. In this way, the lens barrel having the three-group structure can be assembled, but in the present lens barrel structure, the sleeves 24 and 25 of the second and third lens frames are necessarily arranged on the optical axis O of the first lens frame. Since they are fixed in parallel to each other, they can be moved straight in parallel to the first lens frame via the guide rods 26 and 27, and the accuracy with respect to the optical axis between the lens frames can be improved. Become.

[0017]

As described above, in the axial alignment mechanism assembled based on the optical component axial alignment method of the present invention, a jig is used to position the shaft member, and adhesive fixing is performed in this state. Therefore, the present invention, the optical axis accuracy between the lens frame is high, moreover, it is not necessary to increase the processing accuracy of the shaft member supporting portion of the lens frame, it is possible to suppress the component cost, further, It has many remarkable effects, such as the number of assembly steps can be kept low.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing a bonded state of an axial alignment mechanism of an optical component showing the concept of the present invention.

2 is a vertical cross-sectional view of an axial alignment mechanism of the optical component shown in FIG.

FIG. 3 is a vertical cross-sectional view showing a bonded state of a lens frame showing an embodiment of the present invention.

FIG. 4 is a perspective view of a positioning jig used for bonding the lens frame of FIG.

5 is a vertical cross-sectional view showing a bonded state of a lens frame mechanism of a three-group structure using the lens frame of FIG.

FIG. 6 is a vertical cross-sectional view of a lens frame mechanism to which a guide rod is fixed by a press fitting method showing a conventional example.

FIG. 7 is a vertical sectional view of a lens frame mechanism to which a guide rod is fixed by a screwing method showing a conventional example.

FIG. 8 is a vertical sectional view of a lens frame mechanism to which a guide rod is fixed by an insert molding method showing a conventional example.

FIG. 9 is a vertical cross-sectional view of a lens frame mechanism to which a guide bar is fixed by a fitting method showing a conventional example.

[Explanation of symbols]

1,11,21 ………………………………………………………………………………………………………………………………………………………………………………………………………… ……………… Jig 4a ……………………………… Insertion hole 4c ……………………………… Mating surface into which the lens frame is inserted 5, 15, 27… ……………… Adhesive agent 12, 13, 26, 27 ……… Guide rod (shaft member) 14 ……………………………… Positioning jig (jig) 14a ………… ………………… Fitting hole 14c ……………………………… Fitting part (fitting surface that fits in the lens frame)

Claims (2)

[Claims] 1. An optical axis of a lens frame constituting a part of a lens barrel, and a shaft member fixed at a position deviated from the optical axis of this lens frame and for guiding other lens frames in the optical axis direction. In the method of aligning optical components with their axes parallel to each other, the shaft members are loosely fitted to the lens frame, the optical axes of both are made parallel by a jig, and then the two are fixed by an adhesive. A method of aligning the axes of optical components. 2. An optical axis of a lens frame which constitutes a part of a lens barrel, and a shaft member which is fixed at a position deviated from the optical axis of this lens frame and which guides another lens frame in the optical axis direction. In an axis-aligning mechanism for an optical component that is parallel to an axis, the lens frame is provided at a position deviated from the optical axis of the lens frame, and has a loose fitting hole into which the shaft member is loosely fitted. The fitting surface has a fitting surface to be fitted and a fitting hole which is provided at a position overlapping the free fitting hole when the lens frame is fitted to the fitting surface and into which the shaft member is fitted. After the above-mentioned lens frame and the shaft member are fitted and fitted into a jig whose axes are parallel to each other, the loose fitting state of the lens frame and the shaft member is fixed by an adhesive. Alignment mechanism for optical components.