JPH10221584A - Click stop mechanism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent deformation of a diaphragm ring, etc., in a lens tube, etc., and improve operational tone by providing a through hole penetrating the diaphragm ring and inserting a click ball, a compression spring, and a sliding member into this through hole. SOLUTION: A click stop mechanism is provided with a fixed tube 1 for movably holding a lens group and a synthetic resin diaphragm ring 2 for adjusting the diaphragm of a lens tube and a projection part 2a is provided in the diaphragm ring 2 in the vertical direction of the optical axis (x) and in the internal circumferential direction. A through hole 2b is provided in the projection part of the diaphragm ring 2 in such a state as penetrating the projection part 2a in the optical axis (x) direction. A click ball 3, a coil compression spring 4, and a sliding member 5 are arranged in this through hole 2b in this order from the wall 1b side of the fixed tube 1. A pressurizing force for the click stop is not applied on the rotation ring such as the diaphragm ring 2, etc., of the lens tube, etc., in the least so that this constitution can prevent the rotation ring from being deformed by this pressurizing force.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a click stop mechanism suitable for use in an aperture ring or the like in a lens barrel or the like.

[0002]

2. Description of the Related Art Conventionally, a click stop mechanism in a lens barrel or the like has a leaf spring attached to a fixed cylinder in a direction perpendicular to the optical axis so that the tip of the leaf spring is engaged with a click groove provided in an aperture ring. Was composed. However, in this conventional method, since the pressing force of the leaf spring is applied to the synthetic resin diaphragm ring in a direction perpendicular to the optical axis, the diaphragm ring may be deformed in the direction of the pressing force, and the operation condition becomes poor. In some cases, there is a problem that the operating torque of the aperture ring may fluctuate depending on where the user grips the aperture ring.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and the aperture ring and the like are not deformed in a lens barrel or the like, and the operation condition is good.
An object of the present invention is to provide a click stop mechanism in which the operating torque of the aperture ring does not vary depending on where the user grips the aperture ring.

[0004]

In order to achieve the above object, a click stop mechanism according to the present invention comprises: a rotating ring rotatably provided between opposed wall surfaces formed on an outer peripheral portion of a cylindrical portion; A through hole provided in the rotating ring and penetrating in the direction between the wall surfaces, a click ball disposed in the through hole so as to engage with a click groove formed in one of the wall surfaces, And a compression member disposed in the through-hole so as to press against the wall surface of the second member.

According to the present invention, the click ball is disposed in the through hole provided in the rotating ring, and is pressed by the compression member disposed in the through hole to be pressed against one wall surface of the cylindrical portion. Then, when the rotating ring is rotated, the click ball and the compression spring also rotate at the same time, and the click ball engages with the click groove formed on one wall surface while being pressed by the compression member, where the rotating ring is locked, The movement in the rotation direction is regulated. Since the pressing force of the compression member is received on the other wall surface and the one wall surface through the quick ball, the pressing force is not directly applied to the rotating ring. Therefore, the rotating ring is not deformed by the pressing force of the click stop mechanism.

[0006] It is preferable that a sliding member is further provided between the compression member and the other wall surface so as to contact the other of the wall surfaces. According to this configuration,
The sliding member is pressed against the other wall surface by the pressing force of the compression member, and the sliding between the sliding member and the other wall surface is smoothly performed, so that the rotating ring can be more smoothly rotated.

Further, since the pressing force of the compression member is not applied to the rotating ring as described above, the rotating ring can be made of plastic.

By providing a plurality of click grooves at predetermined positions in the circumferential direction on one wall surface, the rotating ring can be locked at a plurality of predetermined positions.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which a click stop mechanism according to the present invention is applied to a lens barrel having an aperture ring will be described below with reference to FIGS. FIG. 1 is a sectional view of the lens barrel according to the present embodiment in the optical axis direction.
The lens barrel in FIG. 1 includes a fixed barrel 1 that movably holds a lens group (not shown), an aperture ring 2 made of synthetic resin for adjusting the aperture of the lens barrel, and a camera body. Attachment part 6 consisting of a claw or the like for attachment to (not shown)
c having a bayonet member 6.

The fixed cylinder 1 and the bayonet member 6 are integrally fixed at an inner peripheral extension 1c of the fixed cylinder 1 and an extension 6b of the bayonet member 6. The fixed cylinder 1 has a wall surface 1b perpendicular to the optical axis x, and the bayonet member 6 has a wall surface 6a perpendicular to the optical axis x. The wall surface 1b of the fixed cylinder 1 and the wall surface 6a of the bayonet member 6 are opposed to each other at a constant interval by the inner peripheral extension 1c.

The aperture ring 2 is provided with a projection 2a in the direction perpendicular to the optical axis x and in the inner circumferential direction. The projecting portion 2a of the aperture ring 2 is disposed in an outer peripheral space formed by the inner peripheral extension 1c, the wall surface 1b, and the wall surface 6a so as to be sandwiched between the opposed wall surfaces 1b, 6a. The aperture ring 6 is provided so as not to move in the optical axis x direction and to be rotatable about the optical axis x.

The projecting portion 2a of the aperture ring 2 is provided with a through hole 2b passing through the projecting portion 2a in the direction of the optical axis x. A click ball 3, a coil-shaped compression spring 4, and a sliding member 5 are arranged in this through hole 2b in this order from the wall 1b side of the fixed cylinder 1. Since the compression spring 4 is in a compressed state and inserted into the through hole 2b, the click ball 3 is pressed against the wall surface 1b of the fixed cylinder 1 by the pressing force in the optical axis x direction generated by the compression spring 4, and is slid. The moving member 5 is pressed against the wall surface 6a of the vanet member 6. The sliding member 5 is in contact with the wall surface 6a of the bayonet member 6, and can smoothly slide with the wall surface 6a.

FIG. 2 is a view of the wall surface 1b of the fixed cylinder 1 as viewed from the front. On the wall surface 1b of the fixed cylinder 1, a plurality of oval click grooves 1a are formed at predetermined angular intervals on a circumference centered on the optical axis x in the direction perpendicular to the paper surface of FIG. The protrusion 2a of the aperture ring 2 is positioned as shown by the broken line in FIG. 2 with respect to the wall surface 1b where the click groove 1a is formed, and the protrusion 2a
Are located such that the center of the click groove 1a coincides with the center of the click groove 1a.

A click ball 3, a compression spring 4, and a through hole 2b of the throttle ring 2 are provided between the wall surfaces 1b and 6a as described above.
When the aperture ring 2 is rotated in the click stop mechanism configured by disposing the sliding member 5, the through hole 2b
Since the click ball 3, the compression spring 4, and the sliding member 5 are inserted in this order from the wall surface 1 b side of the fixed cylinder 1, the click ball 3, the compression spring 4, and the sliding member 5 make the optical axis x simultaneously with the aperture ring 2. Rotate to the center. Since a pressing force is applied to the click ball 3 in the optical axis x direction against the wall surface 1b of the fixed cylinder 1 by the compression spring 4, when the aperture ring 2 rotates and the click ball 3 is positioned in the click groove 1a, The tip of the click ball 3 enters and engages with the click groove 1a, and the click ball 3 is locked by the click groove 1a. In this way, when the click balls 3 are respectively positioned in the plurality of click grooves 1a provided on the wall surface 1b of the fixed cylinder 1,
When the stop function of the click stop mechanism operates, the movement of the aperture ring 2 in the rotational direction at the position of the predetermined click groove 1a is restricted.

As described above, in the present embodiment, the aperture ring 2 penetrates through the aperture ring 2 in a direction parallel to the optical axis x and passes through the aperture 2b.
The click ball 3, the compression spring 4, and the sliding member 5 are inserted into the through hole 2 b, respectively, and the spring member 4 pushes the wall 1 b of the fixed cylinder 1 and the wall 6 a of the bayonet member 6. Since the pressure is applied, the pressing force does not directly apply to the synthetic resin throttle ring, so that there is no problem that the throttle ring is deformed at all. For this reason, in the lens barrel, it is possible to provide a click stop mechanism in which the operating condition is good and the operating torque of the aperture ring 2 does not vary depending on where the aperture ring 2 is gripped.

In the embodiments shown in FIGS. 1 and 2, the present click stop mechanism is applied to a lens barrel. However, the present invention is not limited to this.
The present invention can be applied to any device provided with a click stop mechanism by disposing a rotating ring on a cylindrical portion.

The compression spring is not limited to a coil spring, but may be any spring that generates a pressing force like a disc spring.

[0018]

According to the click stop mechanism of the present invention, since the pressing force for the click stop is not applied to the rotating ring such as the aperture ring of the lens barrel at all, the pressing force deforms the rotating ring. The problem of getting lost is completely eliminated. Therefore, it is possible to provide a click stop mechanism that has a good operation condition and does not have a problem that the operating torque of the rotating ring fluctuates depending on a place where the user grips the rotating ring.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view (optical axis direction) of a lens barrel according to an embodiment of the present invention.

FIG. 2 is a front view of a wall surface of a fixed barrel of the lens barrel shown in FIG.

[Explanation of symbols]

 Reference Signs List 1 fixed cylinder 1a click groove 1b wall surface of fixed cylinder 1c inner peripheral extension 2 aperture ring (rotating ring) 2a protrusion 2b through hole 3 click ball 4 compression spring (compression member) 5 sliding member 6 bayonet member 6a bayonet member 6 Wall 6b Extension of bayonet member 6 6c Mounting part for mounting to camera body x Optical axis

Claims (3)

[Claims] A rotating ring rotatably provided between opposed wall surfaces formed on an outer peripheral portion of a cylindrical portion; a through hole provided in the rotating ring and penetrating in a direction between the wall surfaces; A click ball disposed in the through hole so as to engage with a click groove formed on one side; and a compression member disposed in the through hole so as to press the click ball against the one wall surface. Click stop mechanism. 2. The click stop mechanism according to claim 1, further comprising a sliding member disposed between said compression member and said other wall surface so as to contact said other wall surface. 3. The click stop mechanism according to claim 1, wherein the rotating ring is made of plastic.