JP3303502B2 - Barrier mechanism - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a barrier mechanism, and more particularly, to a barrier mechanism in an optical device such as a camera for protecting an optical system inside the device from dust and the like outside the device.

[0002]

2. Description of the Related Art Various types of barrier mechanisms have been proposed. For example, JP-A-63-239430
Japanese Patent Application Laid-Open No. H11-163873 proposes a lens barrier opening / closing mechanism that opens and closes a barrier by stopping a movable lens barrel at a predetermined position when a lens is retracted, and further moving only a barrier opening / closing member. According to this, since the lens barrel does not move extra, the camera can be made thinner. In addition, 62
JP-A-113335 proposes a camera with a lens barrier in which a barrier is moved from an uncovered position to an optical path hole to a covered position and is moved in an optical axis direction, thereby forcibly inserting the barrier into the optical path hole. I have. According to this, there is an advantage that dust such as dust and dirt does not enter the inside of the camera because the barrier is in close contact with the optical path hole without any gap.

[0003]

Here, the problems which occur in the above-mentioned conventional example due to the relationship between the barrier and the effective optical path will be described with reference to a general conventional example. FIG.
(a) and (b) show a pair of blades P1 and P2 constituting a barrier.
Is schematically shown in a conventional example in which a barrier is opened and closed by moving the same up and down at the front position of the optical system OP.
In the barrier closed state shown in FIG.
2 are in contact at the tip. The contact position at this time is the position S0 on the optical axis AX.

[0004] From the barrier closed state of FIG.
As shown in (5), the blades P1 and P2 are retracted out of the effective optical path, and each tip is located at the position S1. In the effective optical path range at this time, the light ray Q can pass through, but the light rays surrounding it (for example, the light ray R) are cut off. Accordingly, the peripheral light amount drop of the optical system OP becomes large.

Further, the blades P1 and P2 are moved to a position where the light ray R passes.
And each tip is positioned at the position S2. Then, the effective optical path range is widened until the light beam R can pass through, but the diameter of the lens barrel for accommodating the blades P1 and P2 increases as the movement amount of the blades P1 and P2 increases.

Here, the tip position of the blades P1 and P2 in the barrier open state is defined as a position S3 by utilizing the fact that the first surface of the optical system OP is convex. Then, a wide effective optical path range can be secured until the light beam R passes without increasing the diameter of the lens barrel.

Further, the blades P1 and P2 in the barrier open state
If the tip position of the blade P is set to the position S4, the size of the opening diameter of the barrier with respect to the diameter of the lens barrel can be suppressed to be small.
It is possible to secure a large evacuation space for P1 and P2. Therefore, it is possible to reduce the diameter of the lens barrel while securing an effective optical path range until the light beam Q passes.

However, the blade P is located at any of the positions S3 and S4.
Even when the tips of P1 and P2 are located, the blade P
Since the blades 1 and P2 interfere with the optical system OP, the blades P1 and P2 cannot enter the effective optical path of the optical system OP. In any type of conventional barrier mechanism, the opening and closing of the barrier is performed on one plane orthogonal to the optical axis AX, and thus the above-described relationship between the barrier and the effective optical path occurs. Therefore, in order to make the barrier closed state, there is a problem that it is impossible to achieve both reduction of the diameter of the lens barrel and securing of the effective optical path of the optical system.

The present invention has been made in view of such a point, and an object thereof is to secure a sufficiently wide effective optical path range of an optical system in a barrier open state without increasing the diameter of a lens barrel. It is to provide a barrier mechanism that can be used. It is another object of the present invention to provide a barrier mechanism capable of reducing the diameter of a lens barrel without reducing the effective optical path range of an optical system in a barrier open state.

[0010]

To achieve the above object, according to an aspect of, the barrier mechanism according to the first invention, the most position on the object side
For the imaging optical system to be placed , the barrier blade is brought into the effective optical path on the object side of the optical system to close the barrier, and the barrier blade is retracted outside the effective optical path of the optical system to open the barrier. Bali as you do
The blades can be moved in the direction perpendicular to the optical axis of the optical system.
A barrier mechanism having a guide portion for Id, the
A guide portion, wherein at the time of barrier closed, of the optical system
The barrier is located forward of the optical system in the optical axis direction.
The blade moves forward along the optical axis of the optical system so that the blade is positioned, and when the barrier is open, the barrier blade is
The optical system is characterized in that the root moves rearward along the optical axis of the optical system so that a part of the root is located rearward of the tip of the optical system .

[0011] Further, the barrier mechanism according to the second invention comprises:
For an optical system having a convex surface closest to the object side, the barrier is closed by entering a barrier into the effective optical path of the optical system, and the barrier is opened by retracting the barrier outside the effective optical path of the optical system. A barrier mechanism, wherein the barrier is movable between a first position that is orthogonal to an optical axis of the optical system and a second position behind a plane that is in contact with the convex surface. And a driving means for moving the barrier to the first position when the barrier is closed and moving the barrier to the second position when the barrier is opened.

[0012]

According to the structure of the barrier mechanism according to the first aspect of the invention, in the barrier open state, at least a part of the barrier blade is, for example, a plane orthogonal to the optical axis of the optical system and in contact with the convex surface at the tip of the optical system. Located behind
However, as the guide moves forward along the optical axis ,
A space for allowing the barrier blade to enter the effective optical path of the optical system is secured. Therefore, when the guide section is moved forward along the optical axis of the optical system and the barrier blade enters the effective optical path of the optical system, the barrier blade does not interfere with the optical system, so that the barrier closed state is obtained. Can be

When the barrier is closed, the barrier is closed.
Blade is positioned forward of said plane. Similarly to the above, since a large space farther from the optical axis of the optical system between the convex and flat it is present, along with the retreat of the barrier blades to effective optical path outside the optical system, optical system barrier blades A space for moving backward along the optical axis is secured. Therefore, when the retreat of the barrier blade out of the effective optical path of the optical system and the movement of the guide portion rearward along the optical axis of the optical system are performed, the barrier open state is obtained. At this time, the barrier feather by the movement of the guide portion
As the root approaches the optical system, the range of the effective optical path defined by the barrier blade also increases.

According to the structure of the barrier mechanism of the second invention, when the barrier is closed, the driving means moves the barrier to the first position perpendicular to the optical axis of the optical system and forward of a plane in contact with the convex surface. In the first position, the barrier does not interfere with the optical system because there is a larger space between the convex surface and the plane as the distance from the optical axis increases,
The barrier is closed.

When the barrier is opened, the barrier retreats out of the effective optical path of the optical system. However, as described above, there is a larger space between the convex surface and the plane as the distance from the optical axis increases. By means the barrier can be moved to a second position behind the plane. In the second position, as the barrier approaches the optical system, the range of the effective optical path regulated by the barrier is widened.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A barrier mechanism embodying the present invention will be described below with reference to the drawings. Although the present embodiment is a barrier mechanism used for a lens shutter camera, the present invention is not limited to this. In an optical device such as a single-lens reflex camera or a video camera, an optical system inside the device is replaced with external dust or the like. The present invention is also applicable to a barrier device for protecting from a barrier.

FIG. 1 shows a front view of this embodiment when the barrier is closed. FIG. 2 and FIG.
2 shows a cross-sectional structure taken along the line AA of FIG. 1 in a barrier closed state and a barrier open state, respectively. FIG.
Shows a cross-sectional structure taken along the line BB in FIG. 1 in a barrier closed state. In FIG. 4, the barrier guide plate 8, the barrier drive plate 9, and the spring 10 for biasing the opening do not appear in the cross section taken along the line BB, but are combined to clarify the positional relationship with the lens barrel 1. Shown.

In this embodiment, a convex surface (first surface) R
The barrier is closed by allowing the barrier to enter the effective optical path of the optical system 19 with respect to the optical system 19 having
(FIG. 1, FIG. 2, etc.), and a barrier mechanism that retracts the barrier out of the effective optical path of the optical system 19 to open the barrier (FIG. 3). When the barrier is in the closed state, each element (the front decorative plate 3; the wings 4) that enters the effective optical path range H (shown between the light rays L) of the optical system 19 when the barrier is closed.
5; blade drive levers 6, 7, etc.).

Here, the configuration of the entire camera using the barrier mechanism will be described with reference to FIGS. 10 to 12 show the appearance of the camera in a power-off state,
13 and 14 show the appearance of the camera when the power is on. 24 is a power switch, 25 is a body (camera body), 26 is a motor for driving the lens barrel, 27 is a display unit, 28
Is an operation button, and 29 is a release button.

When the power switch 24 provided on the upper surface (FIG. 10) of the body 25 is operated, the power is turned on, and the motor 26 for driving the lens barrel is energized. The driving force of the motor 26 causes the lens barrel 1 to move as shown in FIG.
It moves from the retracted position shown in FIG. 0 to FIG. 12 to the photographable position shown in FIG. 13 and FIG. At this time, at the same time, since a driving member 11 described later retreats with respect to the barrier mechanism,
The barrier is in the closed state shown in FIG. 11 (the blade is fully closed).
From the state shown in FIG. 13 to the barrier open state (blade fully open state).

As shown in FIGS. 2 and 3, in the lens barrel 1, an optical system 19 fixed by a lens frame 13, a barrier mechanism,
Driving means and the like are provided. The optical system 19 is a photographing optical system including the first lens 12 and the second lens 18 as shown in FIGS.
A notch 12a to be described later is formed.

The barrier mechanism is unitized,
In front of the optical system 19 fixed in the lens barrel 1, the entire barrier unit is freely movable back and forth along the optical axis AX of the optical system 19. Therefore, the barrier is also movable, but the movement is perpendicular to the optical axis AX and the convex surface R
This is performed between a first position (barrier mechanism advance position shown in FIG. 2) ahead of a plane TP that is in contact with 1 and a second position (barrier mechanism retreat position shown in FIG. 3) behind the plane TP. .

In the first position, the entire barrier is in the plane T
Must be located ahead of P. This is because if any part of the barrier is behind the plane TP, the barrier cannot be closed. In the second position, at least a part of the barrier needs to be located behind the plane TP. This is because, in the barrier open state, unless at least a part of the barrier is located behind the plane TP, the effective optical path range H is not wider than that of the conventional barrier mechanism in which the barrier is located ahead of the plane TP.

The driving means includes a motor 2 for driving the lens barrel.
6, the driving member 1 interlocked with the motor 26 via the lens barrel 1.
1, an opening spring 10 and the like. The barrier mechanism is
The driving member 11 is configured to obtain a driving force from the lens barrel 1. When the barrier is closed, the barrier moves to the first position in front along the optical axis AX when the barrier is closed, and moves to the second position in the rear along the optical axis AX when the barrier is opened. It will be open.

As shown in FIGS. 2 and 3, a barrier driving plate 9 is rotatably held on the barrier guide plate 8 by a bayonet portion 8c and fitting portions 8b and 9c. When the barrier drive plate 9 rotates, the blade drive levers 6 rotatably held on the barrier guide plate 8
7 is operated, and the blades 4 and 5 are inserted into and removed from the photographing optical path (effective optical path indicated between the light rays L). Further, the front decoration plate 3 that regulates a photographing optical path at a portion (not shown) is fixed to the barrier guide plate 8.

Here, the barrier entry / exit operation will be described in more detail with reference to FIGS. As shown in FIGS. 6 and 7, the blade drive levers 6 and 7 are rotatably held on the barrier guide plate 8 by lever rotation shafts 15, respectively. The blade drive levers 6 and 7 are slidably connected by lever connection pins 17, and are rotatably and slidably connected to the blades 4 by lever connection bosses 4 a at the ends.

Since the lever connecting pin 17 is connected to the blade 5, when a rotational force about the lever rotation shaft 15 is applied to the lever drive pin 14 fixed to the blade drive levers 6, 7, the blade 4,5 are blade drive levers 6,7
Moves between fully closed (barrier closed state) and fully opened (barrier open state). As shown in FIG. 1, the blade straight guides 3a, 3b of the front decorative plate 3
The blade straight-moving pins 5 provided on the blade 5 respectively
a, 5b are engaged, and the opening and closing movement of the blades 4, 5 is guided. The driving force to the lever driving pin 14 is transmitted by the contact of a cam 9d provided on the barrier driving plate 9 as shown in FIGS.
The closing urging spring 16 is configured to transmit the blade closing urging force to the lever drive pin 14 only when the blades 4 and 5 (FIGS. 6 and 7) enter the overcharge area from the fully closed position. I have.

In this embodiment, a barrier of the type using four blades 4 and 5 is adopted. However, the number of blades may be any number, and the rotational force of the barrier drive plate 9 is used to photograph the blades. The mechanism for converting the insertion / retraction operation into the optical path is not limited to this.

Returning to FIGS. 2 and 3, the description will be continued. A rotatable barrier drive plate 9 along the inner peripheral surface of the lens barrel 1,
In addition, the rotation position is fixed (only linear movement is possible.)
A spring (coil spring) 10 for biasing the opening is provided between the first and second barrier guide plates 8. The spring 10 has an optical axis A
Move the barrier drive plate 9 in the rotation direction around X as the rotation center.
(To the barrier guide plate 8) (in the direction of arrow mA in FIGS. 5, 6, and 8). The opening operation of the barrier is performed by the urging force of the spring 10, and the closing operation of the barrier is performed by rotating the barrier driving plate 9 against the urging force of the spring 10.

As shown in FIG. 8, the barrier drive plate 9 is provided with three cam followers 9a. On the other hand, three cam grooves 1a are provided on the inner peripheral portion of the lens barrel 1 so as to correspond to the cam followers 9a, and the cam followers 9a are engaged with the respective cam grooves 1a. As shown in FIG. 6, the barrier guide plate 8 is provided with three linear guides 8a. On the other hand, the linear guide groove 1 is formed on the inner peripheral portion of the lens barrel 1 so as to correspond to the linear guide 8a.
b are provided at three places, and the rectilinear guide 8a is engaged with each rectilinear guide groove 1b. As shown in FIG. 8, the barrier drive plate 9 is provided with drive cams 9b at three locations. On the other hand, driving members 11 (FIGS. 2 and 3) that move in parallel with the optical axis AX in conjunction with the retracting operation of the lens barrel 1 are arranged at positions facing each other on the lens barrel 1 side.

In the barrier closed state, the drive cam 9b and the drive member 11 are in contact with each other as shown in the cam development diagram of FIG. 5 (indicated by a broken line in FIG. 5). Camera body 25 (FIG. 10)
As the lens barrel 1 moves from the retracted position (FIG. 12) to the photographable position (FIG. 14) when the power is turned on, the driving member 11 moves the barrier unit (two points from the broken line position in FIG. 5). (To the position of the chain line). As shown in FIG. 5, since the cam follower 9a is engaged with the cam groove 1a, the driving member 1
Simultaneously with the retraction of 1, the barrier driving plate 9 (FIG. 9) in the barrier closed state rotates while being in contact with the driving member 11 by the driving cam 9b by the urging force of the spring 10 (in the direction of the arrow mA in FIG. 5). Will be. The rotation of the barrier drive plate 9 causes the blades 4 and 5 to retreat outside the imaging optical path, and at the same time,
The barrier drive plate 9 is retracted with respect to the lens barrel 1 and enters the barrier open state (FIGS. 3 and 9). Therefore, at the same time when the blades 4 and 5 are opened, the entire barrier unit is
Approaching and retreating from. When the barrier is open, the barrier mechanism is located rearward with respect to the positions of the lens barrel 1 and the optical system 19 (the second position shown in FIG. 3).
The lens barrel 1 is in a state of being extended so as to be able to take a picture (FIG. 14).

In the closed state of the barrier (FIG. 2), the barrier is located forward of the plane TP. However, a larger space exists between the convex surface R1 and the plane TP as the distance from the optical axis AX increases. When the barrier is opened by the urging force of the spring 10, a space for moving the barrier rearward along the optical axis 19 is secured along with the retreat of the barrier outside the effective optical path of the optical system 19. Become.
Therefore, as described above, the barrier is moved out of the effective optical path of the optical system 19 and the barrier mechanism is moved backward along the optical axis AX, so that the barrier does not interfere with the optical system 19. It will be open.

As the barrier approaches the optical system 19, the range of the effective optical path regulated by the barrier also increases. In addition, as shown in FIG. 3, the front decoration plate 3 regulates the optical path most greatly. In this manner, the effective optical path range H of the optical system 19 when the barrier is open can be made wider than when the barrier is opened at the first position. The notch 12a is provided in a part of the lens 12 in order to further widen the effective optical path range H by securing the retreat amount of the barrier unit as much as possible.

In the barrier open state, the drive cam 9b and the drive member 11 are separated from each other as shown in a cam development diagram of FIG. 5 (shown by a two-dot chain line in FIG. 5). Camera body 25 (FIG. 1)
As the lens barrel 1 moves from the photographable position (FIG. 14) to the retracted position (FIG. 12) when the power is turned off in (0), the driving member 1
1 moves forward while pushing on the barrier unit (from the position of the two-dot chain line to the position of the broken line in FIG. 5). As shown in FIG. 5, since the cam follower 9a is engaged with the cam groove 1a, the barrier driving plate 9 (FIG. 9) in the barrier open state simultaneously applies the urging force ( 5 (in the direction of the arrow mA in FIG. 5), and rotates while being in contact with the drive member 11 by the drive cam 9b. The rotation of the barrier drive plate 9 causes the blades 4 and 5 to enter the imaging optical path, and at the same time, the barrier drive plate 9 advances with respect to the lens barrel 1,
The barrier is closed (FIG. 9). Therefore, at the same time as the blades 4 and 5 are closed, the entire barrier unit is
You will move away from 2. In the closed state of the barrier, the barrier mechanism is located forward of the position of the lens barrel 1 and the optical system 19 (first position shown in FIG. 2), but the lens barrel 1 is in the collapsed state (FIG. 12). is there.

In the barrier open state (FIG. 3), at least a part of the barrier is located behind the plane TP, but as described above, the distance between the convex surface R1 and the plane TP is from the optical axis AX. When the barrier is closed by the driving force of the driving member 11, the barrier moves into the effective optical path of the optical system 19 as the barrier mechanism moves forward along the optical axis AX because there is a larger space as the distance increases. The space for entry will be secured. Accordingly, as described above, the barrier mechanism moves forward along the optical axis AX and the barrier enters the effective optical path of the optical system 19, whereby the barrier is moved to the optical system 19.
The barrier is closed without interfering with the lens and without increasing the diameter of the lens barrel 1.

The barrier opening / closing operation and the advancing / retracting operation of the barrier mechanism are linked to the advancing / retracting operation of the lens barrel 1 (ie, the movement between the retracted position and the photographable position) by the driving member 11. However, the present invention is not limited to this, and may be configured to operate independently. In other words, when changing from the barrier closed state to the barrier open state, the barrier is completely opened and then moved rearward along the optical axis AX. When the barrier is changed from the barrier open state to the barrier closed state, the barrier is moved to the optical axis AX. The barrier may be opened after moving along the front.

As described above, according to the present embodiment, the lens barrel 1
And the securing of a wide effective optical path range H can be achieved at the same time. In other words, the optical system 19 in the barrier open state without increasing the diameter of the lens barrel 1.
The effective optical path range H of the optical system 19 can be sufficiently widened, and as a result, it is possible to suppress a decrease in the amount of light around the optical system 19. Conversely, the diameter of the lens barrel 1 can be reduced without narrowing the effective optical path range H of the optical system 19 when the barrier is open. Thereby, the size of the opening diameter of the front decoration plate 3 with respect to the diameter of the lens barrel 1 can be suppressed small, so that a space for retreating the blades 4 and 5 can be secured. Therefore, a barrier can be configured with a large blade for an optical system having a large effective diameter of the first lens.

Further, according to the present embodiment, the cam is formed by the barrier driving plate 9 which cooperates with the opening and closing of the barrier as described above, and the lens barrel 1 which holds the barrier unit movably in the direction of the optical axis AX of the optical system 19. The driving member 11 is connected to the optical axis AX
, The barrier drive plate 9 is configured to rotate and move in a straight line with respect to the lens barrel 1. Therefore, the barrier opening / closing operation and the barrier mechanism can be performed without adding a new drive source and components. The forward and backward movement can be performed in conjunction with each other, and the cost increase can be reduced.

The relationship between the barrier and the effective optical path in the conventional barrier mechanism is as described above with reference to FIG. 5, but will be described below in comparison with the configuration of this embodiment.

The conventional barrier mechanism opens and closes the barrier at the first position (FIG. 2) while the position is fixed in the direction of the optical axis AX. As can be seen from FIG. However, it is cut by the front decorative plate 3 or the like constituting the barrier. On the other hand, in the present embodiment, when the barrier is in the open state, it retreats to the second position (FIG. 3), so that the light beam L can pass through, and a decrease in the amount of light around the optical system 19 can be suppressed.

If the barrier is arranged at the second position (FIG. 3), a wide optical path is ensured, but the blade 4 and the like constituting the barrier interfere with the lens 12, so that the barrier cannot be closed. Also, move the barrier to the first position (Fig. 2).
Even if the aperture L of the front decoration plate 3 is increased to allow the light beam L to pass through, if the blades 4 and 5 are completely retracted out of the effective optical path when the barrier is opened, the lens barrel 1 This would increase the diameter.

A conventional barrier mechanism (JP-A-63-239)
No. 430, No. 62-113335) differ from the present embodiment in that at least a part of the barrier is not located behind the plane TP in the barrier open state, and the diameter of the lens barrel is small. The above effect of achieving both compactness and securing a wide effective optical path cannot be obtained.

The mechanism disclosed in JP-A-63-239430 is characterized in that a member for opening and closing the barrier is moved after the lens barrel is stopped. Unlike the embodiment in which the barrier mechanism moves forward and backward, the mechanism disclosed in Japanese Utility Model Application Laid-Open No. 62-113335 is significantly different from the embodiment in which the entire barrier mechanism is moved in that only the barrier is moved. In these conventional examples,
It is inevitable that the cost will increase due to the addition of new parts and the complexity of the mechanism.

[0044]

As described above, according to the present invention, the barrier mechanism according to the first invention, when the server rear closed, than the optical system
Since the guide portion moves forward along the optical axis of the optical system so that the barrier blade is located forward, the barrier can be reliably closed in front of the optical system, and In a barrier open state obtained by retreating the barrier blade outside the effective optical path of the system, at least a part of the barrier blade is located behind the tip of the optical system.
So as to be positioned, so moves rearward along the optical axis, without increasing the diameter of the barrel, the effective optical path range of the optical system in the barrier open state can be secured sufficiently wide. As a result, it is possible to suppress a decrease in peripheral light amount of the optical system.

In the barrier mechanism according to the second aspect of the present invention, when the barrier is closed in the optical system having the convex surface closest to the object side by allowing the barrier to enter the effective optical path of the optical system, the driving means is driven by the driving means. Since the barrier is moved to the first position perpendicular to the optical axis of the optical system and ahead of the plane that is in contact with the convex surface, the barrier can be reliably closed in front of the optical system, and In a barrier open state obtained by retracting the barrier out of the effective optical path, the driving unit moves the barrier to the second position behind the plane, so that the barrier can be opened without increasing the diameter of the lens barrel. In this state, the effective optical path range of the optical system can be sufficiently widened. As a result, it is possible to suppress a decrease in peripheral light amount of the optical system.

According to the first and second aspects of the present invention, without increasing the diameter of the lens barrel as described above,
As a result, the effective optical path range of the optical system when the barrier is open can be sufficiently widened, and conversely, the diameter of the lens barrel can be reduced without reducing the effective optical path range of the optical system when the barrier is open. Is also possible. Therefore, even when the present invention is used in an optical system in which the effective diameter of the first lens is large, it is possible to reduce the diameter of the lens barrel.

[Brief description of the drawings]

FIG. 1 is a front view showing a closed state of a barrier according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG. 1 in a barrier closed state.

FIG. 3 is a cross-sectional view taken along the line AA of FIG. 1 in a barrier open state.

FIG. 4 is a sectional view taken along line BB of FIG. 1 in a barrier closed state.

FIG. 5 is a development view of a cam structure in the embodiment.

FIG. 6 is an explanatory diagram showing the state of connection between the blade and the blade drive lever when the barrier is closed, as viewed from the front side.

FIG. 7 is an explanatory diagram showing the state of connection between the blade and the blade drive lever when the barrier is open, as viewed from the front side.

FIG. 8 is an explanatory diagram showing the state of connection between the blade drive lever and the barrier drive plate when the barrier is closed, as viewed from the front side.

FIG. 9 is an explanatory view showing the state of connection between the blade and the blade drive lever when the barrier is open, as viewed from the front side.

FIG. 10 is a plan view of a camera (barrier closed state) in which the present embodiment is used.

FIG. 11 is a front view of a camera (barrier closed state) in which the present embodiment is used.

FIG. 12 is a side view of a camera (barrier closed state) in which the present embodiment is used.

FIG. 13 is a front view of a camera (barrier open state) in which the present embodiment is used.

FIG. 14 is a side view of a camera (barrier open state) in which the present embodiment is used.

FIG. 15 is a diagram schematically showing a relationship between a barrier and an effective optical path.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Lens barrel 1a ... Cam groove 1b ... Straight guide groove 2 ... Holding member 3 ... Front decoration plate 3a ... Blade straight guide 3b ... Blade straight guide 4 ... Blade 4a ... Lever connecting boss 5 ... Blade 5a ... Blade straight pin 5b ... Pin for straight travel of blade 6 ... Lever drive lever 7 ... Blade drive lever 8 ... Barrier guide plate 8a ... Straight guide 8b ... Fitting part 8c ... Bayonet part 9 ... Barrier drive plate 9a ... Cam follower 9b ... Drive cam 9c ... Fit part 9d: Cam 10: Opening spring 11 ... Driving member 12: First lens 12a: Notch 13: Ball frame 14: Lever drive pin 15: Lever rotating shaft 16: Closing bias spring 17: Lever connection Pin 18 Second lens 19 Optical system 24 Power switch 25 Body (camera body) 26 Motor for driving the lens barrel 27 Display unit 28 Operation button 29: Release button R1: Convex surface (first surface) TP: Plane AX: Optical axis L: Light ray

Claims (2)

(57) [Claims] 1. A photographing optical system located closest to an object,
The barrier blade is moved into the effective optical path on the object side of the optical system so as to close the barrier, and the barrier blade is retracted out of the effective optical path of the optical system so that the barrier blade is opened. The optical axis of
A barrier mechanism having a guide portion for movably guiding in a direction orthogonal to the optical system, wherein the guide portion, when the barrier is in a closed state, is located forward of the optical system in the optical axis direction of the optical system. The barrier blade moves forward along the optical axis of the optical system so that the barrier blade is located, and when the barrier is in the open state, a part of the barrier blade is
So as to be positioned behind the front end portion of the optical system, the light
A barrier mechanism that moves backward along the optical axis of the academic system . 2. An optical system having a convex surface closest to the object side.
A barrier mechanism, wherein a barrier is brought into a closed state by entering a barrier into an effective optical path of the optical system, and a barrier is opened by retracting the barrier out of the effective optical path of the optical system, wherein the barrier comprises the optical system. A first position in front of a plane perpendicular to the optical axis of the system and in contact with the convex surface, and a second position in the rear. A barrier mechanism provided with a driving means for moving to a first position and moving to the second position when opened.