JP2704349B2 - Lens holding device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
The present invention relates to a holding device for fixing and holding one or a plurality of held members simultaneously.

[0002]

2. Description of the Related Art A configuration commonly used to fix and hold lenses to a lens barrel will be briefly described. FIG. 5 shows a configuration in which a lens is bonded to a lens barrel using an adhesive. FIG. 6 shows a configuration in which a ring-shaped spring member is fitted into a groove provided in the lens barrel to fix the lens to the lens barrel. FIG. 7 shows a configuration in which a female screw portion is provided in a lens barrel, and a male screw portion is provided in a ring-shaped member to be mounted, and these are screw-connected and fixedly held by a tightening force.
A configuration combining these configurations is also known.

[0003]

The above prior arts have the following disadvantages, respectively, and none of them are satisfactory. When the adhesive shown in FIG. 5 is used, satisfactory adhesive strength may not be obtained even if the curing time of the adhesive is sufficiently long. Therefore, in environmental tests,
Often, high ratings for reliability were not obtained. Further, some adhesives contain toxic substances. A non-toxic organic adhesive must be used for worker safety, and various problems remain from the viewpoint of working environment and efficiency. Furthermore, when the adhesive 17 cures, the lens 13 may be distorted to deform the lens surface shape. Further, when a plurality of members are incorporated, members other than the members fixed by the adhesive may move due to vibration or impact, and the performance may not be secured.

When the lens 13 is held and fixed by screw connection between a ring-shaped holding device 15 provided with a male screw shown in FIG. 7 and a female screw 16 in a lens barrel frame 14, a direction (diameter) perpendicular to the optical axis is required. Direction) is inevitably required, and there is a possibility that lens misalignment may occur. Since the entire circumference is not evenly tightened when tightening, the lens is tilted, which causes one-sided blur due to eccentricity. Further, when fixing with an adhesive and a screw type via another member, the cost and man-hour of the member increase, and the cost increases.

As shown in FIG. 6, a ring-shaped holding device 18 having a spring property in the radial direction is mounted on the lens barrel frame 14 to fix and hold the lens. A groove must be provided, and the size of the groove is limited in a plastic molded resin lens barrel, and the reliability of holding the lens is poor.
Further, in the case of a lens barrel having a small outer diameter, the groove in the outer diameter direction is extremely difficult in mold production. Therefore, individual groove processing by a lathe is required, and the manufacturing cost is increased. Since the positions of the grooves are fixed, if errors in the thickness of several lenses accumulate on the positive side, it becomes difficult to fit in the grooves, and in the opposite case, there is a gap between the lenses, thereby lowering the performance. In addition, when a predetermined portion of the lens barrel is crimped to hold the lens in the lens barrel frame, there is little guarantee that the lens will be securely fixed and held by the restoring force of the pressed portion. In addition, it is difficult to use an adhesive in a machine for automatic assembly in which components constituting a lens are housed in a lens barrel and the lenses are fixed and held,
In the case of the screw type, the mechanical structure becomes complicated. An object of the present invention is to provide a lens holding device which can solve the above-mentioned problems and is particularly suitable for mass production.

In order to achieve the above object, a lens holding apparatus according to the present invention comprises a lens barrel, a lens inserted into the lens barrel and engaged with the lens from one side of the lens barrel to hold the lens into the lens barrel. A lens holding device comprising holding means fixed in a frame, wherein the lens barrel has a shape for guiding the outer periphery of the lens to restrict movement from one side to the other side, and the lens barrel is provided on the receiving side. The holding means has an inner periphery larger than the outer shape of the above. The holding means is an annular elastic thin plate, which secures the effective diameter of the lens at the center and contacts the lens from one side at the center opening and at the outer periphery. a plurality of guiding outside diameter portion of diameter smaller than the diameter of the pressing means holding portion of the barrel, is ahead <br/> Tan径are deflected while and extending outwardly in the guiding outer diameter portion minutes sufficiently large and <br/> the press than the outer shape of the guiding outer diameter portion Has a plurality of projections larger than the inner diameter of the means holding unit, press the pressing means after insertion of the lens into the barrel from the side that is deflected the press-fitted into the barrel the central opening the lens A portion outside the outer diameter of the lens within the outer periphery of the holding means is further pressed down from a position in contact with the surface of the lens to fix and hold the lens by elastic pressure between the lens barrel and the holding means holding portion. I have.

[0007]

In the lens holding device having the above-mentioned structure, even if one lens or a plurality of lenses are housed in the lens barrel, it can be fixedly held at the same time.
It is possible to provide a low cost lens holding device which is excellent in reliability and workability.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in more detail with reference to the drawings. FIG. 1 shows an embodiment of a lens assembly using the lens holding device according to the present invention. As shown in the drawing, this lens assembly includes the first lens 1 and the second lens
The lens 2, the diaphragm 4, and the third lens 3 are inserted into the lens barrel 5 provided with the holding means 6 and held by the holding means 7. In this embodiment, the lens barrel 5 is made of a molded plastic resin, but it is of course possible to use metal such as aluminum or brass. The shape of the embodiment of the holding means 7 will be described in more detail with reference to FIGS. The holding means 7 has a plurality of portions 8 slightly smaller than the inner diameter of the holding means 6 for holding the lens barrel and functioning as guides when press-fitting the lens holding device. Slightly larger than the inner diameter of the holding means 6 of the holding means,
Further, a projection 9 which is angled in a direction opposite to the insertion direction is provided. An opening 10 having an inner periphery in contact with the surface of the first lens 1 is provided at the center of the holding means 7. The diameter of the opening 10 must be large enough to secure the effective diameter of the lens. The guide outer diameter portion 8 of the holding means 7, the projection 9 used for holding and fixing, and the center opening 1
No. 0 has been subjected to high-precision press working so as to sufficiently maintain coaxiality and roundness. In this embodiment, a thin metal plate is used as the holding means 7. The pressing force can be adjusted by selecting an appropriate plate pressure. When a metal plate is used, black plating (matting) is preferably performed. Although an example in which a metal plate is used has been described, a sufficiently elastic holding means can be formed by using other materials such as plastic.

Next, a process of manufacturing a lens assembly using the lens holding means having the above configuration will be described with reference to FIG. First, the lens barrel 5 in which the lenses are stored is placed on an assembly jig, and is mounted on the upper part of the entrance of the holding means 6 of the holding means 6 so that the bending direction of the projection 9 of the holding means 7 is directed upward. The pressing jig 12 arranged vertically above the lens barrel 5 and the holding means 7 is lowered, and only the holding means 7 is pressed. The position of the stopper 11 of the pressing jig is adjusted so that the pressing jig 12 stops at a position where the first lens 1 is slightly pressed down from a position where the first lens 1 comes into contact with the pressing means 7. The elasticity of the holding means 7 of the lens holding device and the elasticity of the holding means 6 of the lens barrel 5 allow the lens 1 and the holding means 7 and the holding means 7 to be moved.
And the holding means holding portion 6 of the lens barrel 5 are simultaneously fixed. The pressing jig 12 is manufactured so as to press only the root portion of the pressing means 7 where the projection 9 is bent, and an excessive pressing force is not applied to the lens housed in the lens barrel.

[0010]

As described above, the lens holding device according to the present invention comprises a lens barrel, a presser inserted into the lens barrel and engaged with the lens from one side of the lens barrel to fix the lens in the lens barrel frame. Means. Although the configuration is extremely simple, it is possible to securely hold not only one lens but also a plurality of lenses. It is suitable for automatic assembly of lenses and can provide a low-cost and highly reliable lens assembly.

[Brief description of the drawings]

FIG. 1 is a sectional view of a lens assembly using an embodiment of a lens holding device according to the present invention.

FIG. 2 is a perspective view showing an embodiment of lens holding means of the lens holding device according to the present invention.

FIGS. 3A and 3B are views showing an embodiment of a lens pressing means of the lens holding device according to the present invention, wherein FIG. 3A is a front view and FIG.

FIG. 4 is an explanatory diagram for explaining a manufacturing process of a lens assembly using the embodiment of the lens holding device according to the present invention.

FIG. 5 is an explanatory diagram of a conventional lens holding device using an adhesive.

FIG. 6 is an explanatory view of a conventional lens holding device using a ring-shaped spring member.

FIG. 7 is an explanatory view of a conventional lens holding device using a screw connection lens holding means.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 1st lens 2 2nd lens 3 3rd lens 4 Aperture 5 Lens barrel main body 6 Lens barrel pressing means holding part 7 Holding means

Claims (1)

(57) [Claims] 1. A lens holding device comprising: a lens barrel; and pressing means inserted into the barrel and engaged with the lens from one side of the barrel to fix the lens in the barrel frame. The cylinder has a shape that guides the outer circumference of the lens to restrict movement from one side to the other side, and has a holding means holding portion having an inner circumference larger than the outer shape of the lens on the receiving side; Is an annular elastic thin plate having a central opening in which the effective diameter of the lens is secured at the center and which comes into contact with the lens from one side, and a plurality of outer guides having a diameter smaller than the inner diameter of the holding means of the lens barrel pressing means at the outer periphery. Between the outer diameter portion and the outer diameter portion for guidance, the outer portion extends outward and is warped to one side.
The tip diameter is sufficiently larger than the outer diameter of the guide outer diameter
Has KuKatsu said pressing means holder plurality of projections larger than the inner diameter of the central pressed by pressing the pressing means after insertion of the lens into the barrel from the side which is deflected the said barrel A portion outside the outer diameter of the lens is further pressed down from the position where the opening contacts the surface of the lens within the outer periphery of the holding means, and the lens is fixed and held by elastic pressure between the lens barrel and the holding means holding portion. The lens holding device configured as described above.