JP3687367B2 - Lens barrier opening / closing mechanism - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a lens barrier opening / closing mechanism provided in front of a lens barrel for protecting a photographing lens of a camera.
[0002]
[Prior art]
A conventional photographing lens barrier opening / closing mechanism provided on the front surface of the lens barrel for protecting the photographing lens of the camera will be described with reference to FIGS. 1A and 1B are views of the main part of the lens barrier opening / closing mechanism, wherein FIG. 1A is an exploded perspective view thereof, and FIG. 1B is a plan view of a cam portion. FIG. 2 is a front view with the barrier opened.
[0003]
1 and 2, a cam 401 is provided at the tip of a linear guide 40 that linearly advances and retracts a lens barrel 6 in which a lens barrel including a helicoid screw (not shown) is extended and retracted. Yes. A rotation pin 31 of a rotation ring 3 that opens and closes the lens barrier 2 that is a lens cover that is incorporated in the lens barrel 6 and protects the photographing lens is inserted and fitted into the cam groove of the cam 401. . The rectilinear guide 40 is provided integrally with the fixed rectilinear guide ring 4. Therefore, when the lens barrel 6 guided by the fixed rectilinear guide 40 moves forward and backward, the rotating pin 31 is moved forward and backward. It is moved along the cam groove of the cam 401, and the rotation ring 3 is rotated clockwise and counterclockwise.
[0004]
In the lens barrier 2, a barrier rotation shaft hole 21 is inserted and fitted into a barrier rotation shaft (not shown) implanted in the front ring 5 fixed to the lens barrel 6, and further, in the barrier drive pin hole 22 of the lens barrier 2, When the barrier drive pin 32 of the rotation ring 3 is inserted and fitted, and the rotation ring 3 rotates clockwise and counterclockwise, the lens barrier 2 rotates about the barrier rotation shaft hole 21, It opens and closes. Accordingly, the lens barrier 2 opens and closes as the lens barrel 6 moves forward and backward as described above.
[0005]
[Problems to be solved by the invention]
In the conventional barrier opening / closing mechanism as described above, the lens barrier 2 is closed when the lens barrel 6 incorporating the photographic lens is retracted into the camera body, and the lens is in a state where the photographic lens is brought out to a shootable position for photographing. In order for the barrier 2 to open, it is necessary to provide a reciprocating cam 401 having a cam-like groove for rotating the rotating ring 3 in the clockwise and counterclockwise directions in the rectilinear guide 40.
[0006]
Accordingly, in order to provide the rectilinear cam 40 with the groove-shaped reciprocating cam 401, the lateral width of the rectilinear guide 40 needs to be increased. However, when the lateral width of the rectilinear guide 40 is increased, a dead space 61 is generated between the rectilinear guide 40 and the lens barrel 6. Alternatively, it may be necessary to escape the straight guide 40 depending on the internal component arrangement. However, in either case, the diameter of the lens barrel 6 is increased, and the camera is eventually increased.
[0007]
The present invention has been made to solve the above problems. That is, an object of the present invention is to provide a lens barrier opening / closing mechanism that can protect a photographing lens without enlarging the camera.
[0008]
[Means for Solving the Problems]
The object of the present invention is achieved by adopting the following configuration.
[0009]
That is, in the lens barrier opening / closing mechanism provided on the front surface of the lens barrel for protecting the photographing lens, the rotation of the rotating ring that opens and closes the barrier guides the straight movement of the lens barrel in the optical axis direction. There line by a cam provided on two rectilinear guides each cam provided to each of the two straight guides, one for rotation in one direction of the rotating ring and the other opposite the pivot ring A lens barrier opening and closing mechanism for rotating a direction .
[0011]
Further, the lens barrier opening / closing mechanism characterized in that a cam provided on each of the two linear guides is provided at a tip of the linear guide.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Next, embodiments of the lens barrier opening / closing mechanism of the present invention will be described in detail with reference to FIGS. 3 and 4. However, the present invention is not limited to the embodiments described below.
[0014]
FIG. 3 is an exploded perspective view of the main part of the lens barrier opening / closing mechanism of the present embodiment. 4A and 4B are views of the main part of the barrier opening / closing mechanism, wherein FIG. 4A is a plan view of the upper straight guide showing the relative position between the upper cam and the rotating pin when the barrier is closed, and FIG. 4B is a front view when the barrier is closed. The front view seen from the ring side, (c) is a bottom view of the lower linear guide showing the relative position between the lower cam and the rotating pin when the barrier is closed, and (d) is the upper cam when the barrier is opened. (E) is a front view seen from the front ring side when the barrier is opened, and (f) is a view of the lower cam and the rotating pin when the barrier is opened. It is a bottom view of the lower side straight advance guide which shows a relative position.
[0015]
3 and 4, the configuration of the lens barrier opening / closing mechanism for opening and closing the lens barrier 2 according to the present embodiment by rotating the rotation ring 3 is the same as that of the conventional lens barrier opening / closing mechanism described with reference to FIGS. 1 and 2. The linear guide 40 is divided into an upper linear guide 41 and a lower linear guide 42, and the cam 401 is divided into an upper cam 411 and a lower cam 421. 3 is the same except that the upper and lower rotation pins 31 are rotated by the upper cam 411 and the lower cam 421. In other words, the rotating ring 3 is rotated by cams provided on the two linear guides installed at substantially symmetrical positions for guiding the lens barrel 6. The number of linear guides is not necessarily limited to two, and two or more linear guides can be used. However, two linear guides provided with cams are preferable.
[0016]
4, the rotation of the rotation ring 3 in the opening direction of the lens barrier 2 is as shown in FIGS. 4 (a), 4 (b), and 4 (c). When the lens barrel is extended, the rotating pin 31 is moved in the direction of arrow C by the lower cam 421. This movement is a clockwise rotation of the rotating ring 3. At the same time, since the upper straight guide 41 also moves in the direction of arrow A, the pivot pin 31 moves in the direction of arrow B along the upper cam 411. That is, the rotation ring 3 can be rotated in the clockwise direction. Accordingly, the lens barrier 2 is implanted in the front ring 5 by the clockwise rotational movement of the barrier drive pin 32 implanted in the rotation ring 3 inserted and fitted in the barrier drive pin hole 22 of the lens barrier 2. Rotating in the direction of arrow E around the barrier rotation shaft hole 21 inserted and fitted to the barrier rotation shaft 51, the lens barrier 2 is opened and the state shown in FIG.
[0017]
At this time, the tip 331 of the click spring 33 of the rotating ring 3 gets over the latching portion 62 of the lens barrel 6 due to the elastic deformation of the click spring 33, and from the state of FIG. 4 (b) to FIG. 4 (e). To the state. Accordingly, the open state of the lens barrier 2 is stably maintained as it is, and the reliability of the barrier is improved.
[0018]
Next, when the lens barrier 2 changes from the open state to the closed state, as shown in FIGS. 4D, 4E, and 4F, the upper straight guide 41 moves in the direction of the arrow A ', and accordingly When the lens barrel is retracted, the pivot pin 31 is moved in the arrow B ′ direction by the upper cam 411. This movement is a counterclockwise rotation of the rotating ring 3. At the same time, the lower rectilinear guide 42 also moves in the direction of arrow D ′, so that the pivot pin 31 moves in the direction of arrow C ′ along the lower cam 421. That is, the rotation ring 3 can be rotated counterclockwise. Therefore, the lens barrier 2 is implanted in the front ring 5 by the counterclockwise rotational movement of the barrier drive pin 32 implanted in the rotation ring 3 inserted and fitted in the barrier drive pin hole 22 of the lens barrier 2. Rotating in the direction of the arrow E ′ around the barrier rotation shaft hole 21 inserted and fitted in the barrier rotation shaft 51, the lens barrier 2 is closed and the state shown in FIG.
[0019]
At this time, the tip 331 of the click spring 33 of the rotating ring 3 gets over the locking portion 62 of the lens barrel 6 due to the elastic deformation of the click spring 33, and from the state of FIG. 4 (e) to FIG. 4 (b). To the state. Therefore, the closed state of the lens barrier 2 is stably maintained as it is, and the reliability of the barrier is improved.
[0020]
Further, the linear guide 40 is thus divided into an upper linear guide 41 and a lower linear guide 42, and the lower cam 421 provided on the lower linear guide 42 rotates the rotating ring 3 in the clockwise direction. Since the upper cam 411 provided on the upper straight guide 41 is for counterclockwise rotation of the rotating ring 3, the lateral width of the straight guide can be reduced, and the dead space as shown in FIG. Was able to be reduced. Therefore, it was possible to reduce the size of the camera without increasing the lens barrel diameter.
[0021]
The above-mentioned cam provided on each of the linear guides is provided at the tip of the linear guide, because the opening / closing mechanism is operated in the immediate vicinity of the barrier opening / closing mechanism, so that no extra parts are required, and thus the camera is reduced in size. However, it is preferable because the barrier opening / closing mechanism is prevented from becoming complicated. In addition, one of the linear guides should have a high precision finish to the required limit by reducing the fitting gap with respect to the lens barrel of the straight running member, and the other one should have a large fitting gap. This is also preferable from the viewpoint of preventing an increase in cost due to component processing accuracy.
[0022]
【The invention's effect】
According to the present invention, a lens barrier opening / closing mechanism capable of protecting the photographing lens while maintaining reliability without increasing the size of the camera is provided.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating a main part of a conventional lens barrier opening / closing mechanism.
FIG. 2 is a front view of a lens barrel when a barrier of a conventional lens barrier opening / closing mechanism is open.
FIG. 3 is an exploded perspective view of a main part of the lens barrier opening / closing mechanism of the present embodiment.
FIG. 4 is a diagram illustrating a main part of a lens barrier opening / closing mechanism according to the present embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Lens barrier opening / closing mechanism 2 Lens barrier 21 Barrier rotating shaft hole 22 Barrier drive pin hole 3 Rotating ring 31 Rotating pin 4 Linear guide ring 40 Linear guide 401 Cam 41 Upper linear guide 411 Upper cam 42 Lower linear guide 421 Lower cam 5 Front ring 6 Lens barrel

Claims (2)

In the lens barrier opening and closing mechanism provided on the front surface of the lens barrel for protecting the photographing lens,
The rotation of the rotary ring for opening and closing the barrier, have rows by a cam provided on two rectilinear guides each to guide a linear movement in the optical axis direction of the lens barrel,
One of the cams provided on each of the two linear guides is for rotating the rotating ring in one direction, and the other is for rotating the rotating ring in the opposite direction. mechanism. 2. The lens barrier opening / closing mechanism according to claim 1, wherein the cams provided on the two linear guides are provided at the distal ends of the linear guides .

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