JPH10246849A - Lens barrel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make structure simple so as to realize miniaturization by turning a turning cam barrel by a driving lever and a driving barrel respectively so that a holding barrel may be moved in an optical axis direction. SOLUTION: This lens barrel is provided with the driving lever 4 formed in the turning cam barrel 3 and the driving barrel 6 fixed with the cam barrel 3 and driving the cam barrel 3. After the cam barrel 3 is turned by the lever 4 formed in the cam barrel 3 so that the holding barrel 1 may be moved in the optical axis direction, the driving barrel 6 and the cam barrel 3 are fixed through a cam fixing screw and the driving barrel 6 is turned within the range of a turning regulation part formed in the driving barrel 6, so that the cam barrel 3 is rotated and the holding barrel 1 is moved in the optical axis direction. Thus, the holding barrel 1 is moved in the optical axis direction by a specified amount in plural stages only by turning the cam barrel 3. Then, the holding barrel 1 is moved in the optical axis direction by driving the operation lever 8 of the turning barrel 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a focal position adjusting mechanism for a lens barrel.

[0002]

2. Description of the Related Art As a conventional lens barrel, a lens barrel described in Utility Model Registration No. 251143 is known.
In this lens barrel, when the focus back position is adjusted, the cam pin on the side of the second lens group is normally used in the circumferential cam groove of the cam barrel by rotating the cam barrel via the rotary barrel to outside the normal use area. It faces the extended groove continuously formed outside the region, locks the acting force on the cam pin by the spring for urging the second lens group, fixes the phase by the cam means, and then the cam by the connector By interrupting the rotation transmission between the cylinder and the rotating cylinder, rotating the rotating cylinder in a relatively rotatable state, the straight helicoid mechanism of the rotating cylinder and the holding cylinder with the cam cylinder stopped, With the distance between the first lens group and the second lens group kept constant,
The entire photographing lens group may be moved back and forth with respect to the film surface, so that the focus back position can be adjusted to a required position.

In order to perform zooming or macro operation, the rotary barrel and the cam barrel are connected to each other, and the cam barrel is rotated with the rotation of the rotary barrel so that the guide barrel holding the second lens group is moved along the optical axis. Move back and forth in the direction.

[0004]

A conventional lens barrel is:
With the above configuration, separate mechanisms are required for focus back adjustment and zooming or macro operation, respectively, and a special member is required for connection between each mechanism. However, there is a problem that the number of parts increases and it is difficult to reduce the size of the lens barrel.

An object of the present invention is to provide a lens barrel that solves the above-described problems, and has an object to obtain a lens barrel that can be reduced in size with a simple structure.

[0006]

SUMMARY OF THE INVENTION In order to solve this problem, the present invention provides a rotary cam barrel provided with a drive lever, and by rotating the drive lever, the rotary cam barrel is rotated, and the holding barrel is connected to the optical axis. After moving in the direction, the driving cylinder and the rotating cam cylinder are fixed, and the driving cylinder is rotated, whereby the rotating cam cylinder is rotated within the range of the rotation restricting portion formed in the driving cylinder, and the holding cylinder is rotated. It is configured to move in the axial direction.

Thus, the holding cylinder can be moved in the optical axis direction in a plurality of steps only by rotating the rotating cam cylinder.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An invention according to a first aspect of the present invention is directed to a holding cylinder containing a plurality of lenses, and a rotating cam barrel which engages with the holding cylinder and moves the holding cylinder in the optical axis direction. When,
A guide shaft for guiding movement of the holding cylinder in the optical axis direction, a driving lever for the rotating cam cylinder, and a driving cylinder fixed to the rotating cam cylinder for driving the rotating cam cylinder; A lens barrel for rotating the rotary cam barrel and moving the holding barrel in the optical axis direction by means of a lever and the drive barrel, respectively, wherein the rotation of the rotary cam barrel causes the holding barrel to rotate in a plurality of stages. Since the lens barrel can be moved in the axial direction, the lens barrel can be simplified.

According to a second aspect of the present invention, there is provided a holding cylinder accommodating a plurality of lenses, a rotating cam cylinder which engages with the holding cylinder and moves the holding cylinder in the optical axis direction, and A guide shaft for guiding the movement of the cylinder in the optical axis direction, a driving lever for the rotating cam cylinder, a driving cylinder fixed to the rotating cam cylinder for driving the rotating cam cylinder, and a holder for mounting the CCD And a stopper of the holder and a rotation restricting portion formed on the driving cylinder, wherein the rotation restricting section and the stopper are brought into contact with each other to restrict a rotation range of the rotary cam cylinder by the driving cylinder. Since the rotation range of the cam barrel due to the rotation of the drive cylinder can be performed by the rotation restricting portion of the drive cylinder and the stopper of the holder, the lens barrel is It can be simplified and downsized.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is an exploded perspective view showing a lens barrel according to an embodiment of the present invention, and FIG. 2 is a side view showing a part of the lens barrel according to the embodiment of the present invention.

1 and 2, reference numeral 1 denotes a holding cylinder containing a plurality of lenses, 2 denotes a driving unit formed on the holding cylinder 1,
Is a rotating cam barrel that engages with the drive unit 2 of the holding barrel 1 to move the holding barrel 1 in the optical axis direction, 4 is a drive lever formed on the rotating cam barrel 3, and 5 is formed on the rotating cam barrel 3. A cam groove 6 is fixed to the rotary cam barrel 3 and a drive cylinder 7 for driving the rotary cam barrel 3.
Denotes a cam fixing screw for fixing the rotating cam cylinder 3 and the driving cylinder 6;
Is an operation lever formed on the driving cylinder 6, 9 is a rotation restricting section formed on the driving cylinder, 10 is a guide shaft for guiding the movement of the holding cylinder 1 in the optical axis direction, 11 is a holder for mounting a CCD, and 12 is a holder for mounting the CCD. A stopper formed on the holder 11, a holding plate 13 for holding the guide shaft 10, and a holding plate fixing screw 14 for fixing the holding plate 13 to the holder 11.

The operation of the lens barrel configured as described above will be described below. First, focus back adjustment will be described. Focus back adjustment is performed by the drive cylinder 6
The rotation cam barrel 3 is rotated by the drive lever 4 formed on the rotation cam barrel 3 with one end of the rotation restricting part 9 formed on the holder 11 in contact with the stopper 12 formed on the holder 11, thereby holding the rotating cam barrel 3. The drive unit 2 formed on the cylinder 1 is driven by the cam groove 5 formed on the rotary cam cylinder 3, and the holding cylinder 1 is guided by the guide shaft 10 held on the holder 11 by the holding plate 13 and the holding plate fixing screw 14. It moves by a predetermined amount in the optical axis direction. Thereafter, the rotating cam barrel 3 and the driving barrel 6 are fixed by the cam fixing screw 7, and the focus back adjustment is completed.

Next, the macro operation will be described. In the macro operation, the driving cylinder 6 is rotated by the operation lever 8 formed on the driving cylinder 6 from the focus back adjustment completed state. Since the driving cylinder 6 and the rotating cam barrel 3 are fixed by the cam fixing screw 7, the rotating cam barrel 3 is also rotated, and the holding cylinder 1 is moved in the optical axis direction in the same manner as the focus back adjustment. be able to. The range of macro operation is
Is restricted between one end and the other end which are in contact with the stopper 12 during the focus back adjustment of the rotation restricting portion 9 formed in the above.

[0014]

As described above, according to the present invention, after the rotating cam barrel 3 is rotated by the driving lever 4 provided on the rotating cam barrel 3 to move the holding barrel 1 in the optical axis direction, the driving barrel 6 The rotating cam cylinder 3 is fixed by a cam fixing screw 7, and the driving cylinder 6 is rotated within the range of the rotation restricting portion 9 formed on the driving cylinder 6 so that the rotating cam cylinder 3 is rotated. The cylinder 1 is moved in the optical axis direction.

Thus, the holding barrel 1 can be moved in the optical axis direction in a plurality of steps by a predetermined amount only by the rotation of the rotary cam barrel 3, so that the lens barrel can be simplified and downsized. Can be In addition, since the holding cylinder 1 can be moved in the optical axis direction by driving the operation lever 8 of the rotating cylinder 6, an effect is obtained that the operation from the camera body side becomes easy.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing a lens barrel according to an embodiment of the present invention.

FIG. 2 is a side view showing a part of the lens barrel according to the embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Holding cylinder 3 Rotating cam cylinder 4 Drive lever 6 Drive cylinder 9 Rotation restricting part 11 Holder 12 Stopper

Claims (2)

[Claims] 1. A holding cylinder accommodating a plurality of lenses, a rotating cam cylinder which engages with the holding cylinder and moves the holding cylinder in the optical axis direction, and guides the movement of the holding cylinder in the optical axis direction. A driving shaft for driving the rotating cam barrel fixed to the rotating cam barrel and a driving lever for driving the rotating cam barrel.
A lens barrel for rotating the rotating cam barrel to move the holding barrel in the optical axis direction. 2. A holding cylinder accommodating a plurality of lenses, a rotating cam cylinder which engages with the holding cylinder and moves the holding cylinder in the optical axis direction, and guides the movement of the holding cylinder in the optical axis direction. A guide shaft, a drive lever for the rotary cam barrel, a drive barrel fixed to the rotary cam barrel for driving the rotary cam barrel, a holder for mounting a CCD, a stopper for the holder, A lens barrel including a rotation restricting portion formed in a cylinder, and restricting a rotation range of the rotary cam cylinder by the driving cylinder by bringing the rotation restricting portion into contact with the stopper.