JP4149049B2 - Lens barrel with filter operating device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a lens barrel having a rear insertion filter device used in a telephoto lens, particularly a lens having a long focal length and a lens having a bright F value, and more particularly, a polarizing filter is used as a rear insertion filter. The present invention relates to a lens barrel having a filter operating device that can handle the above.
[0002]
[Prior art]
When using a polarizing filter to shoot an image of a camera interchangeable lens except for reflected light such as the water surface, the polarizing filter must be mounted according to the polarization of the reflected light. Since the lens is used by rotating from the outside, it can be used by screwing it into the accessory screw at the tip of the lens to be used. It was attached to the accessory screw and used to rotate the polarizing filter directly.
[0003]
A large-aperture lens such as a telephoto lens with a filter attached to and detached from a lens barrel proposed by Japanese Utility Model Laid-Open Nos. 58-159524, 58-172922 (Japanese Utility Model Publication 3-42424), etc. A flexible plug-in filter is used. However, conventionally, in this type of plug-in type filter, the above-described polarizing filter that requires rotation with the filter mounted on the lens barrel cannot be used. Therefore, in general, when using a polarizing filter, the photographer finds and uses his intended image while observing the viewfinder image of a single-lens reflex camera, as in the past. On the other hand, it was difficult to use a filter that could not reach the tip of the lens, or a lens whose focusing mechanism was a front group rotation type. Therefore, a proposal has been made that the polarizing filter plate is held by the filter frame, the filter frame is rotatably supported by the filter holder, and the filter frame is rotated by an operation member provided on the filter holder and a transmission mechanism such as a gear, a belt, and a roller. No. 59-95328, No. 60-186430, No. 64-15208 and the like.
[0004]
[Problems to be solved by the invention]
However, the above proposals have a filter holder in the filter holder and a filter operation part in the lens barrel body. However, the operation part is small and the purpose is to operate the operation part in small increments. The operation amount was not obtained, and the operability was not sufficient. In addition, there is a problem that it is difficult to adjust the amount of rotation of the polarizing filter because the operation feeling and the feeling when the polarizing filter is attached to the tip of the lens and rotated to operate are different.
[0005]
[Means for Solving the Problems]
A filter holding member that holds a filter frame in which a filter plate is fitted is provided in a plug-in type filter holder that is detachably mounted in a lens barrel, the filter holding member is rotatable, and the filter holding member is connected to a connecting gear. Thus, the problem was solved by providing a rotating filter operation ring on the outer periphery of the lens barrel. In addition, by making the connecting gear a stepped gear, the feel of the rotation of the filter operating ring and the amount of rotation of the filter can be adjusted by adjusting the gear ratio.
[0006]
【Example】
The lens barrel of the present invention will be described below with a polarizing filter attached thereto according to the illustrated embodiment. FIG. 1 shows a lens barrel to which a plug-in type filter holder is attached. Reference numeral 10 denotes a lens barrel body having a filter operating device, 11 denotes a filter operating ring, and 20 denotes a plug-in type filter holder. The plug-in type filter holder 20 is attached to the lens barrel body 10 by being inserted into an opening (not shown) provided in the lens barrel body 10.
[0007]
As shown in the enlarged front view and the cross-sectional view of FIGS. 2A and 2B, this plug-in type filter holder 20 includes a filter holding ring 21 that rotatably supports a filter frame 23 in which a polarizing filter plate 22 is fitted. Yes. An external gear 21 a is integrally provided on the outer peripheral portion of the filter holding ring 21.
[0008]
On the other hand, FIG. 3 is a cross-sectional view of the lens barrel showing the vicinity of the filter operation ring 11 provided in the lens barrel body 10, where 11 is a filter operation ring, and 12 is a connecting gear. An external gear 12a is provided on the outer periphery of the connection gear 12, and meshes with an internal gear 11a provided on the inner periphery of the filter operation ring 11. As shown in the sectional view of FIG. A holder presser 13 is rotatably attached. As a result, by rotating the filter operation ring 11, the connection gear 12 meshed with the internal gear 11a rotates around the connection gear shaft 12b. The rotation of the connecting gear 12 actuates the external gear 21a of the filter holding ring 21 meshing with the connecting gear 12, thereby rotating the filter holding ring 21 and rotating the polarizing filter plate 22 fitted in the filter frame 23. It acts as a polarizing filter.
[0009]
FIG. 5 is a cross-sectional view of the vicinity of the connection gear showing a connection gear in which the above-described connection gear 12 is constituted by a step gear. Reference numeral 50 is a connecting gear constituted by a step gear, and has a first external gear 51 and a second external gear 52. The first external gear 51 meshes with the internal gear 11 a provided on the filter operation ring 11, the second external gear 52 meshes with the external gear 21 a provided on the filter holding ring 21, and the rotation of the filter operation ring 11 is transmitted via the connecting gear 50. To the filter holding ring 21. By adjusting the gear ratio of the first external gear 51 and the second external gear 52 provided on the connecting gear 50, the rotation amount of the filter operation ring 11 and the rotation amount of the filter holding ring can be adjusted, and the operation feeling of the filter operation can be improved. Can be set.
[0010]
Next, the operation of the lens barrel having the filter operation member configured as described above will be described.
[0011]
First, a polarizing filter is screwed into the filter holding ring 21 of the plug-in type filter holder 20 shown in FIG. At this time, since the filter holding ring 21 is rotatable, the polarizing filter is screwed by pressing the knurled surface 21 b provided on the filter holding ring 21. Next, the plug-in type filter holder 20 is attached to the lens barrel body 10 in the state shown in FIG. In order to rotate the polarizing filter plate 22 through the filter frame 23, the filter operation ring 11 provided on the outer peripheral portion of the lens barrel body 10 may be rotated. When the filter operation ring 11 is rotated, the connecting gear 12 is rotated as shown in FIG. 3, the filter holding ring 21 meshed with the connecting gear 12 is rotated, and the filter frame 23 screwed into the filter holding ring 21 is rotated. The polarizing filter plate 22 can be rotated. Accordingly, the polarizing filter plate 22 can be adjusted to the polarization of the reflected light in order to take an image without the reflected light such as the water surface (or by intentionally increasing the reflected light).
[0012]
【The invention's effect】
As described above, in the present invention, the holding member that holds the filter to be mounted by being inserted into the lens barrel is rotatably held by the filter holder, and the operation member is provided on the outer periphery of the lens barrel. Further, since the transmission means of the operation member is provided, the filter can be rotated with the feeling when the filter is mounted outside with the filter holder inserted.
[Brief description of the drawings]
FIG. 1 is a lens barrel to which a plug-in type filter holder is attached.
FIG. 2 is an enlarged front view and a cross-sectional view of the plug-in type filter holder shown in FIG.
FIG. 3 is a cross-sectional view of a lens barrel showing the vicinity of a filter operation ring.
4 is a cross-sectional view taken along the line AA in FIG. 3;
FIG. 5 is a cross-sectional view showing the vicinity of a connecting gear constituted by a step gear.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Lens barrel main body 11 Filter operation ring 11a Internal gear 12 Connection gear 12a External gear 12b Connection gear shaft 13 Filter holder holder 20 Insertion type filter holder 21 Filter holding ring 21a External gear 21b Knurled surface 22 Polarization filter plate 23 Filter frame 50 Connection gear 51 First external gear 52 Second external gear

Claims (2)

A lens barrel having operation means for operating a plug-in type filter holder that is detachably mounted in the lens barrel, and a filter that rotatably holds a filter frame in which a filter plate is fitted in the plug-in type filter holder A lens barrel having a filter operating device, characterized in that a holding member is provided and a filter operating ring for rotating the filter holding member via a connecting gear is provided around the entire lens barrel. A lens barrel having operation means for operating a plug-in type filter holder that is detachably mounted in the lens barrel, and a filter that rotatably holds a filter frame in which a filter plate is fitted in the plug-in type filter holder 2. A lens barrel having a filter operating device according to claim 1, wherein a connecting gear for connecting the holding member and the filter operating ring provided around the entire periphery of the lens barrel is formed of a stepped gear.

Images