JPH06214144A - Len barrel provided with light shielding plate - Google Patents

Abstract

PURPOSE:To firmly fix a light shielding plate and to stably hold the light shielding plate. CONSTITUTION:As to a structure for arranging the light shielding plate 12 at the inner surface side of a lens barrel 2 for holding a fixed lens group, an engaging pawl 13 which is engaged with a mounting hole 8 of the lens barrel 2 is installed on the light shielding plate 12, and also, a small projection 14 is installed on the end part of the abutting surface of the light shielding plate 12. By having such a structure, the engaging pawl 13 is pushed into the mounting hole 8 and engaged with the hole 8 while bringing the small projection 14 into contact with the inner surface of the lens barrel 2, so that the light shielding plate 12 is deflected and attached to the lens barrel. Then, an elastic repulsive force is generated on the light shielding plate 12, and the light shielding plate 12 is firmly fixed in the lens barrel 2 by the elastic repulsive force.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light-shielding plate mounting structure for a lens barrel having a light-shielding plate for preventing internal reflection of the lens barrel in video cameras and other various cameras.

[0002]

2. Description of the Related Art Some video cameras, cameras and the like have a lens barrel provided with a light-shielding plate. The light-shielding plate reflects incident light such as sunlight on the inner surface of the lens barrel to form an image recording surface. To prevent it from reaching.

FIG. 5 shows the internal structure of a conventional lens barrel, which is an example of a lens barrel for a focus lens. In FIG. 5A, a fixed lens group 1 is held by a lens barrel 2, and a movable lens group 3 is held by a movable frame 4 inside the lens barrel 2. The moving frame 4 is slidably supported along the guide shaft 5, and the moving lens group 3 is moved in the optical axis direction by lens driving means (not shown). Then, on the bottom surface side of the lens barrel 2, as shown in FIG. 5B [sectional view taken along the line BB of FIG. 5A], a light shielding plate 6 is arranged along the inner surface of the lens barrel 2. It

The shading plate 6 is formed on the inner surface in the moving range of the sawtooth shading fold moving lens group 3, and two engaging claws 7 provided on the outside are opened in the wall of the lens barrel 2. It is fixed to the lens barrel 2 by engaging with the mounting hole 8. That is, due to the demand for miniaturization of the camera, the inside of the lens barrel 2 becomes narrower, and in recent years, fogging due to internal reflection of the lens barrel 2 cannot be ignored. The light-shielding plate 6 prevents reflection of light such as sunlight reaching the inner surface of the lens barrel 2 mainly from above via the fixed lens group 1, and a good image without fog can be obtained. . Further, as a conventional example similar to the above-mentioned light shielding plate, there is one disclosed in Japanese Utility Model Laid-Open No. 4-65305.

[0005]

However, in the lens barrel having the light shielding plate 6, as shown in FIG. 5, the engaging claw 7 is simply engaged with the mounting hole 8 of the lens barrel 2. Therefore, there is a problem that backlash is likely to occur in the mounting structure, and the light shielding plate 6 cannot be firmly fixed and held in a stable state.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a lens barrel having a light shield plate that can firmly fix the light shield plate and hold it stably. is there.

[0007]

In order to achieve the above object, the present invention provides a lens barrel having a light-shielding plate in which a light-shielding plate is arranged on the inner surface side of a lens-barrel for holding a lens. An engaging claw that engages with the mounting hole of the lens barrel is provided, and a small protrusion is provided on the abutment surface of the light shielding plate. When the engaging claw is engaged with the mounting hole of the lens barrel, the light shielding plate is provided. Is configured to press the inner surface of the lens barrel by the small protrusion.

[0008]

According to the above construction, the small projection is brought into contact with the inner surface of the lens barrel while the engaging claw is pushed into the mounting hole for engagement, so that the light shielding plate is attached to the lens barrel in a bent state. . Therefore, the small protrusions press the inner surface of the lens barrel due to the elastic repulsive force of the light shielding plate, whereby the light shielding plate is firmly fixed to the lens barrel.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a cross-sectional view (cross-section AA of FIG. 2) of a lens barrel having a light-shielding plate according to an embodiment, and FIG. 2 shows a side cross-sectional view of this lens barrel. Has been done. In FIG. 2, as in the conventional case, the fixed lens group 1 is held by the lens barrel 2, and the moving lens group 3 is held by the moving frame 4 inside the lens barrel 2. A guide shaft 5 is arranged inside the lens barrel 2, and the movable frame 4 is slidably supported by the guide shaft 5. As the lens driving means, for example, a combination of a lead screw provided on the motor shaft and a rack portion provided on the moving frame 4 side can be used. According to this, the rotational movement of the lead screw is converted into a linear movement in the optical axis direction by the rack portion, whereby the movable lens group 3 is moved in the optical axis direction.

Further, two mounting holes 8 are provided on the bottom of the lens barrel 2.
Is provided, and the light shielding plate 12 of the embodiment is attached to the attachment hole 8. That is, the light shielding plate 12 is made of an elastic material such as plastic and has a sawtooth-shaped light shielding fold formed on its inner side surface in order to prevent reflection of incident light causing fog. Then, two engaging claws 13 are provided on the outer side surface of the light shielding plate 12, and in the embodiment, four small projections 14 are provided on the four corners of the outer side surface.

FIG. 3 shows a front view of the light shielding plate 12,
FIG. 4 shows a bottom view of the light shielding plate 12. As shown in FIG. 3, when the engagement claw 13 engages with the engagement position 100 of the mounting hole 8, the inner surface position (circle) of the lens barrel 2 becomes 200, but the small projection 14 has the inner surface position. 200 to length L
It is formed so as to exceed (for example, a few millimeters).
Further, as shown in FIG. 4, in the embodiment, two small protrusions 14 are arranged at positions concentric with the respective engaging claws 13.

In such a shading plate 12, the engaging projection 13 is attached to the mounting hole 8 while the small projection 14 is brought into contact with the inner surface of the lens barrel 2.
It can be attached to the lens barrel 2 by being pushed in and engaged. At this time, as shown in FIG. 1, the small projection 14 formed so as to project by the length L is attached to the lens barrel 2.
The light shielding plate 12 is bent as a result of pressing the inner surface of the light shielding plate 12. Therefore, elastic repulsive force is generated in the light shielding plate 12,
Due to this elastic repulsive force, the light shielding plate 12 is firmly fixed to the inner surface of the lens barrel 2.

In the above embodiment, the four small projections 14 are arranged on the concentric circles with the engaging claws 13. However, the small projections may be arranged on a position other than the concentric circles. It may be a single piece, and it is possible to obtain a predetermined fixed state by arranging the small protrusions at a position where the elastic repulsive force can be applied.

Further, although the case where the shading plate 12 of the embodiment is provided only on the bottom surface side has been described, a plurality of shading plates can be arranged at other portions or the entire area, and the same applies to this case. Is possible.

[0015]

As described above, according to the present invention,
The light shielding plate is provided with an engaging claw that engages with the mounting hole of the lens barrel,
Further, a small protrusion is provided on the contact surface with the inner surface of the lens barrel, and when the engaging claw is engaged with the mounting hole of the lens barrel, the light shielding plate presses the inner surface of the lens barrel by the small protrusion. Therefore, the shading plate is held on the lens barrel under a firmly fixed state,
There is an advantage that play is prevented.

[Brief description of drawings]

FIG. 1 is a view showing a configuration of a lens barrel having a light shielding plate according to an embodiment of the present invention, and is a cross-sectional view taken along the line AA of FIG.

FIG. 2 is a side sectional view of a lens barrel of an example.

FIG. 3 is a front view showing a protruding state of small protrusions on the light shielding plate of the embodiment.

FIG. 4 is a bottom view of the light shielding plate according to the embodiment.

5A and 5B are views showing a lens barrel having a conventional light shielding plate, FIG. 5A being a side sectional view, and FIG. 5B being BB in FIG.
FIG.

[Explanation of symbols]

 2 ... Lens barrel, 4 ... Moving frame, 6,12 ... Shading plate, 7,13 ... Engaging claw, 8 ... Mounting hole, 14 ... Small projection.

Claims (1)

[Claims] 1. A lens barrel having a light-shielding plate in which a light-shielding plate is disposed on the inner surface side of a lens-barrel for holding a lens, wherein the light-shielding plate is provided with an engaging claw that engages with a mounting hole of the lens-barrel. A small projection is provided on the contact surface of the light shielding plate, and the light shielding plate presses the inner surface of the lens barrel by the small projection when the engaging claw is engaged with the mounting hole of the lens barrel. A lens barrel having a light-shielding plate.