JPH0579517U - Lens unit - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a lens unit that can easily correct misalignment caused by a fitting clearance between a lens and a lens barrel. [Structure] Various lenses 11, 12, 13 in the lens barrel 10
In the lens unit configured by incorporating the lens via the lens frames 14, 15, and 16, the lens barrel 10 and the lens frame 14,
15 and 16, the lens frame attracts (or repels) magnetic force
By the action, the magnet means is provided to float in the lens barrel and perform centering. With the above configuration, the magnetic force attracting action on the entire circumference of the lens frame allows the lens frame to be always placed in the center of the fitting clearance without coming into contact with the inner surface of the lens barrel. Matching is done.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to improvement of a lens unit used in various optical devices such as cameras and copying machines.

[0002]

[Prior Art]

 An example of a conventional lens unit is shown in FIG. In the figure, 1 is a lens barrel, 2, 3 and 4 are lenses, 4, 5 and 6 are lens frames, and 8 and 9 are spacing rings.

[0003]

[Problems to be solved by the device]

 In the lens unit having the above configuration, when the centered lens frame is inserted into the lens barrel, the lens frame is within the barrel, and only the clearance between the lens frame and the barrel (about 10 to 20 μm) It will be misaligned, so it is difficult to further improve the core accuracy.

[0004]

[The purpose of the device]

 The present invention has been made to solve the above problems, and an object thereof is to provide a lens unit capable of improving the core accuracy.

[0005]

[Means for Solving the Problems]

 The present invention is a lens unit configured by incorporating various lenses into a lens barrel through a lens frame, and the lens frame is floated in the lens barrel by the attraction and repulsion of magnetic force between the lens barrel and the lens frame. The gist is that the magnet means for centering is provided.

[0006]

[Action]

 In the lens unit configured as described above, the lens frame is aligned with the center of the lens barrel without contacting the inner surface of the lens barrel by the attraction and repulsion action of the magnet means.

[0007]

【Example】

 FIG. 1 shows an embodiment of the present invention. In the figure, 10 is a lens barrel made of a magnetic material, 11, 12, 13 are lenses, 14, 15 and 16 are lens frames made of a magnetic material, and 17 and 18 are spacing rings. The lens barrel 10 and the lens frames 14, 15 and 16 are magnetized so that the N pole and the S pole are opposed to each other in the radial direction over the entire circumference. With this configuration, the lens frames 14, 15 and 16 are always placed in the center of the fitting clearance without coming into contact with the inner surface of the lens barrel due to the magnetic force absorbing effect on the entire circumference thereof, and no action is required. Of course, the centering of the lens barrel is performed.

In the above-described embodiment, an example is shown in which the lens barrel and the lens frame made of a magnetic material are magnetized over the entire circumference. However, as shown in FIG. 2, both are magnetized at equal intervals. However, the core can be aligned. In this case, partial magnetization is possible by using an anisotropic magnetic material, but it is necessary to prevent the lens frame from rotating.

Further, a non-magnetic material may be used for the lens barrel and the lens frame, and a magnet piece may be attached to the opposing surface.

[0010]

[Effect of the device]

 As described above, according to the present invention, it is possible to obtain the lens unit capable of correcting the misalignment caused by the outer diameter error of the lens and the fitting clearance between the lens barrel and the lens barrel by simple means.

[Brief description of drawings]

FIG. 1 is a sectional view of a lens unit showing an embodiment of the present invention.

FIG. 2 is an end view of a lens unit that is partially magnetized.

FIG. 3 is a sectional view of a conventional lens unit.

[Explanation of symbols]

 10 lens barrel 11,12,13 lens 14,15,16 lens frame 17,18 spacing ring

Claims (1)

[Scope of utility model registration request] 1. A lens unit comprising various lenses incorporated in a lens barrel via a lens frame, wherein the lens frame is floated in the lens barrel by magnetic attraction and repulsion. A lens unit characterized in that it is provided with a magnet means for taking it out.