JPH11202186A - Focus adjusting device for lens - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a distinctive click stop feeling and to prevent a lens part from falling owing to excessive rotation. SOLUTION: In this focus adjusting device for lens, the lens part 1 is fitted with a stopper member 5, a lens holder 2 is provided with a projection 2b having a step, and the fitting position of the stopper member 5 or the abutting position where the stopper member 5 abuts against the projection 2b is selected. The rotational restriction position of the lens part can be adjusted finely by the selection and the rotational restriction position of the lens part and the position of just focusing can be put very close to each other.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a focus adjusting device for a rotary lens used in a camera or the like, and more particularly to a focus adjusting device for a lens having a stopper mechanism.

[0002]

2. Description of the Related Art In recent years, personal computers have become widespread, and simple cameras with a single focus are often used for capturing images and the like. There is a type in which the focus is adjusted by rotating a lens.

A conventional focus adjusting device for a camera of the type that adjusts the focus by rotating a lens will be described below.

FIG. 5 is a perspective view showing the structure of a main part of a conventional camera focus adjusting device, FIG. 6 is a sectional view of another conventional camera focus adjusting device, and FIG. It is sectional drawing of the focus adjustment apparatus of the camera of an example.

In FIG. 5, reference numeral 1 denotes a lens portion having a male screw 1a for rotating the outer periphery of a cylindrical portion, and 2 denotes a female screw 2a for attaching the lens portion 1 to the inner periphery of the cylindrical portion.
This is a lens holder having:

The lens portion 1 is screwed into the tube portion of the lens holder 2 and the lens portion 1 is tightened and rotated so as to be integrated with the lens holder 2. When the focus is adjusted, the screw is rotated in the tightening direction. When the focus is adjusted to the near side, the screw is rotated in the direction in which the screw is removed, and the focus is adjusted to an arbitrary position and used.

Further, as shown in FIG. 6, a lens holder 2 is arranged in a housing 4 and a lens portion 1 is screwed into the lens holder 2 from the front side of the housing 4 to restrict screwing. is there.

Further, as shown in FIG. 7, the lens unit 1 and the lens holder 2 are arranged inside the housing 4 and
In some cases, a part of the flange is made to come out of the slit 3 of the housing 4 and rotated, and a front part of the housing 4 is provided with a portion for preventing the lens portion 1 from coming off.

[0009]

In the structure of the focus adjusting device for a camera shown in FIG. 5, when the lens portion 1 is tightened, the lens portion 1 is gradually rotated and stops while being tight, so that there is a clear moderation. There was a problem that a stopper feeling could not be obtained. Also, when focusing the lens at infinity by rotating the lens unit 1 in the tightening direction,
Since it is very difficult to match the screw-tightened position with the infinity-side focus position, an infinity-side focus position is required before tightening the screw. There is a problem that a margin is inevitably generated, and in that margin, the focus cannot be adjusted anywhere and the usability is poor.

In the configuration shown in FIG. 6,
When the lens unit 1 is rotated to the near side to adjust the focus to the close side, if the lens unit 1 is rotated too much,
Had the problem of dropping in the direction of

Further, the structure shown in FIG. 7 can prevent the lens portion 1 from dropping off, but cannot provide a clear modest stopper feeling, and has a problem that the usability and the operation feeling are extremely poor. Was.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned conventional problems. A stopper which can prevent the lens portion from falling off due to excessive rotation by restricting the rotation of the lens portion in the tightening direction and the forward direction, and has a clear moderation. Achieved a feeling and realized a configuration that allows fine adjustment of the rotation stopper position of the lens part, making it possible to extremely close the lens part stopper position and the just focus position, dramatically improving usability and operational feeling. It is an object of the present invention to provide a lens focus adjusting device.

[0013]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a lens having a configuration in which a screw tube of a lens unit is screwed into a screw tube of a lens holder and the lens unit is rotated to adjust the focus. The lens portion, wherein a plurality of stopper mounting holes are provided in a flange of the lens portion, and a stopper member is mounted on one of the stopper mounting holes such that a rear end protrudes rearward. Is provided with a projection having a step so as to reduce the width of the tip portion, and it is possible to select the mounting position of the stopper member, or to select whether the stopper member comes into contact with the small width portion or the large portion of the projection. The configuration is as described above.

According to the present invention, a stopper member and a projection constitute a rotation restricting mechanism in the tightening direction and the forward direction of the lens portion, so that a clear modest stopper feeling can be obtained, and the lens portion is rotated excessively. Dropout can be prevented. Further, by selecting the mounting position of the stopper member or selecting whether the stopper member comes into contact with the small width portion or the large portion of the projection, the rotation restriction position of the lens portion can be finely adjusted, and the rotation restriction position of the lens portion can be finely adjusted. And the just focus position can be extremely close to each other, thereby realizing a lens focus adjustment device with greatly improved usability and operational feeling.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 of the present invention has a structure in which a lens unit is screwed into a lens holder, and the lens unit is rotated to adjust the focus. A focus adjustment device for a lens, wherein a stopper member is attached to the stopper mounting hole such that a rear end protrudes rearward, and a projection for preventing rotation of the lens unit by providing contact with the stopper member is provided on the lens holder. This makes it possible to obtain a clear modest stopper feeling, and has the effect of restricting excessive turning in the lens tightening direction and the dropping direction.

According to a second aspect of the present invention, in the lens focus adjusting apparatus according to the first aspect, the projection of the lens holder has a step so as to reduce the width of the front end portion, and the stopper member Is designed to prevent rotation of the lens part by contacting either the narrow part or the large part, and in addition to restricting excessive rotation in the lens tightening direction and the dropping direction, the stopper member By contacting either the narrow portion or the large portion, the rotation of the lens portion can be finely adjusted to prevent rotation.

According to a third aspect of the present invention, in the lens focus adjusting apparatus according to the first aspect, the lens portion has a plurality of stopper mounting holes provided in an annular arrangement. The stopper member is attached to one of the plurality of stopper attachment holes, and the function of adjusting the rotation restricting positions on the infinity side and the near side can be adjusted by arbitrarily selecting the attachment position of the stopper member. .

According to a fourth aspect of the present invention, in the lens focus adjusting device according to the first, second or third aspect, the stopper member attached to the attachment hole of the lens portion is formed of a screw and projects rearward. The length can be adjusted freely, and a simple, small, and standard structure that allows fine adjustment of the rotation restriction position during focus adjustment beyond the pitch of the holes for attaching the lens rotation stopper members It has an action that can be made with parts.

According to a fifth aspect of the present invention, in the lens focus adjusting device according to the first or second or third aspect, stopper members having different lengths are selected for the stopper mounting holes of the lens portion. It is made freely attachable,
Similarly, it has a function of enabling a simple, small, and standard component to make a structure capable of finely adjusting the rotation restricting position at the time of focus adjustment to be equal to or larger than the pitch of the hole for mounting the rotation stopper member of the lens.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. (Embodiment 1) FIG. 1 is a perspective view showing a main part of a lens focus adjusting apparatus according to Embodiment 1 of the present invention, and FIGS.
FIG. 4 is a side view for explaining the rotation restricting operation of the lens unit. In the drawings, the same components as those of the conventional example are denoted by the same reference numerals.

In FIG. 1, reference numeral 1 denotes a lens portion having a male thread 1a on the outer periphery of a cylindrical portion thereof, and a plurality of stopper mounting holes 1b arranged in a ring shape in a flange portion. 2
Denotes a lens holder, which has a female screw 2a on the inner periphery of the cylindrical portion, and has a projection 2b protruding forward at a position outside the base of the cylindrical portion. The projection 2b has a step on the side so that the width of the tip is small and the base is large.

The cylindrical portion of the lens portion 1 is screwed into the cylindrical portion of the lens holder 2 and tightened while rotating the lens portion 1 in the y direction to focus on a predetermined position on the infinity side. The stopper member 5 made of a screw is
Is screwed into the stopper mounting hole 1b closest to the hole so that its rear end projects rearward.

In the above configuration, when the stopper member 5 made of a screw is mounted, one of the states shown in FIGS. 2 and 3 can be considered. At this time, in the case of FIG. 2, the clearance with the projection 2b is small, so that the stopper is used as it is. In the case of FIG. 3, the clearance of the stopper member 5 with respect to the projection 2b is large, so that the length of the stopper member 5 is increased. , Using the step provided on the projection 2b,
To make the rotation margin small. Therefore,
The tolerance of the stopper mounting hole 1b, in which the stopper member 5 is tightened, up to the stopper is reduced by a step difference.

Also, an arbitrary focus position is selected on the side close to the lens unit 1, and the length of the stopper member 5 is selected so that the clearance with respect to the protrusion 2b is reduced as in the case of the infinity side as shown in FIG. By stopping,
The focus position on the near side can be adjusted, and
A stopper for preventing the lens portion 1 from falling off can be used.

[0025]

As is apparent from the above description, according to the present invention, a stopper member and a projection constitute a rotation restricting mechanism in the direction in which the lens portion is tightened and in the forward direction, and a clear modest stopper feeling can be obtained. It is possible, and it is possible to prevent the lens portion from falling off due to excessive rotation. In addition, by selecting the mounting position of the stopper member or selecting whether the stopper member comes into contact with the small width portion or the large portion of the projection, the rotation regulating position of the lens portion can be finely adjusted,
The rotation control position of the lens unit and the just-focus position can be extremely close to each other, and a focus adjustment device for a lens in which usability and operability are dramatically improved can be realized.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a configuration of a main part of a focus adjusting device for a lens according to a first embodiment of the present invention;

FIG. 2 is a side view for explaining a rotation restricting operation of the focus adjusting device of the lens.

FIG. 3 is a side view for explaining a rotation restricting operation of the lens unit.

FIG. 4 is a side view for explaining a rotation restricting operation of the lens unit.

FIG. 5 is a perspective view showing a configuration of a main part of a conventional camera focus adjustment device.

FIG. 6 is a cross-sectional view of another conventional camera focus adjustment device.

FIG. 7 is a cross-sectional view of another conventional example of a camera focus adjustment device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Lens part 1a Male screw 1b Stopper mounting hole 2 Lens holder 2a Female screw 2b Projection 4 Housing 5 Stopper member y Tightening direction z Dropping direction

Claims (5)

[Claims] 1. A lens unit is screwed into a lens holder, and the lens unit is rotated to adjust the focus so that a rear end of the lens unit protrudes rearward into a stopper mounting hole provided in the lens unit. A focus adjusting device for a lens, wherein a stopper member is attached to the lens holder, and a projection for preventing rotation of the lens unit by contacting the stopper member is provided on the lens holder. 2. A structure in which a projection of a lens holder has a step so as to reduce a width of a front end portion, and a stopper member abuts on one of a small width portion and a large portion to prevent rotation of the lens portion. The focus adjusting device for a lens according to claim 1, wherein: 3. The lens unit according to claim 1, wherein said lens portion has a plurality of stopper mounting holes provided in an annular arrangement, and a stopper member is mounted in one of said plurality of stopper mounting holes. Lens focus adjustment device. 4. The focus adjustment of a lens according to claim 1, wherein the stopper member attached to the attachment hole of the lens portion is made of a screw, and a length of the stopper projecting rearward is adjustable. apparatus. 5. The lens focus adjusting device according to claim 1, wherein stopper members having different lengths are selectively mounted in the stopper mounting holes of the lens portion.