JP3294975B2 - Camera barrier movement restriction 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 movement restricting mechanism for restricting the movement of a barrier plate for protecting a photographic lens of a camera.

[0002]

2. Description of the Related Art In recent years, a barrier plate for protecting a photographic lens from dirt and impact has been provided to improve portability and morphological beauty when the photographic lens is retracted when not in use (when not photographing). A so-called capsule type camera has been commercialized. In this type of camera, when the barrier plate covering the unused photographic lens is opened, the drive switch is turned on, the photographic lens is extended, and the camera is ready for photography. In this state, if the barrier plate is slightly moved to the shielding position covering the taking lens,
The drive switch is turned off and the taking lens is retracted to the storage position. Then, when the taking lens is completely retracted, the barrier plate can be completely closed.

[0003] Therefore, in such a capsule type camera, even if the barrier plate is closed at a stretch from the state of use, the barrier plate abuts on the photographing lens while the photographing lens is not completely retracted into the storage position.
For this reason, a mechanism is required to lock the barrier plate, which has been slightly moved toward the shielding position to drive the lens driving motor, until the taking lens is completely retracted. Such a barrier movement limiting mechanism is usually
It is driven using the driving force at the time of extension and retraction of the taking lens.

The barrier movement restricting mechanism includes a lock claw for moving the barrier plate to an open position and moving the barrier plate to a position where the barrier plate can be locked at the open position in conjunction with extension of the photographing lens. There is. When the photographing lens is retracted, the lock claw receives a driving force when the photographing lens advances and retreats through an interlocking mechanism such as a gear train, and is moved to a lock release position in a direction opposite to the lock position. In such a barrier movement restriction mechanism, for example, when the photographing lens is driven from the photographing position to the storage position, if the barrier plate is pressed strongly to close the barrier plate, the barrier plate engages with the lock claw. This is pressed at the lock position. In this state, when the photographing lens being driven reaches the storage position, an interlocking mechanism such as a gear train forcibly applies a force to the fixed lock claw. For this reason, a large load is applied to the interlocking mechanism and the drive system of the photographing lens, and there is a possibility that malfunction or breakage may occur.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide an interlocking mechanism such as a gear train and a driving system for a photographing lens even when an external force is applied by a user's erroneous operation in a state where a barrier plate is opened, based on the above-mentioned problems in a barrier movement restricting mechanism. It is an object of the present invention to provide a barrier movement restricting mechanism capable of reliably preventing a problem in which a large load is applied to the device, resulting in malfunction or breakage.

[0006]

SUMMARY OF THE INVENTION In order to achieve the above-mentioned object, the present invention provides a photographic lens which can move back and forth between a photographing position and a storage position; and moves to a shielding position covering the photographic lens located at the storage position and an open position to open. A lock lever that pivots to a lock position engageable with a lock portion of the barrier plate when the barrier plate is opened; and a lock lever that rotates when the photographing lens moves to the storage position. A rotating member that moves; a lock releasing member that is coaxially mounted on the rotating member and is engageable with the lock lever; a rotation member that is provided between the rotating member and the unlock member, and that is added to the lock lever. When the dynamic resistance is equal to or less than a predetermined value, the unlocking member is rotated integrally with the rotating member to rotate the lock lever in the unlocking direction. It is characterized in that a clutch mechanism which does not rotate the lock lever by idle with respect to the unlocking member.

The rotating member is formed by a lock operating gear pivotally mounted on a camera body, which rotates in a locking direction and an unlocking direction by receiving a driving force when the photographing lens advances and retreats between a photographing position and a storage position. The lock release member can be constituted by a cam member which is rotatably and coaxially connected to the lock operation gear. The lock operation gear includes a locking portion that locks the cam member at different relative angles in the lock direction and the lock release direction, and the first lock operation gear and the cam member are provided therebetween. With the torsion spring,
It is desirable that the cam member be relatively rotated in the unlocking direction until the cam member is locked by the locking portion so that the cam member is always rotated integrally.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on illustrated embodiments. FIG. 1 is a front view showing a so-called capsule type camera to which the present invention is applied, with a barrier plate opened. When the camera 10 opens the barrier plate 20 covering the photographing lens 14 in the non-use state,
A drive switch (not shown) is turned on, and based on this, the photographing lens 14 is extended to be in a photographable state. In this state, when the barrier plate 20 is slightly moved in the direction covering the photographing lens 14, the drive switch is turned off, and based on this, the photographing lens 14 is retracted to the storage position.

The camera 10 has the photographic lens 14, the strobe 9 and the finder window 17 on the front wall 12a of the camera body 12, and has the shutter button 8 on the upper surface. Further, guide grooves 12b are provided above and below the front wall 12a so as to extend in a direction perpendicular to the lens optical axis of the photographing lens 14 (the left-right direction of the body 12). This guide groove 12
b, the barrier plate 20 is movable in a direction orthogonal to the lens optical axis of the photographing lens 14, that is, a shielding position covering the photographing lens 14 retracted into the storage position, and an opening position opening the photographing lens 14. It is movably fitted in. The barrier plate 20 is compared by a click stop mechanism (not shown) between the open position and the closed position so that a predetermined force is required when moving the barrier plate 20 from the open position to the closed position or from the closed position to the open position. Locked with light force. The barrier plate 20 has a rib (lock portion) 20a on the rear surface thereof extending in the left-right direction of the camera body 12 at the center in the up-down direction.

The camera body 12 is provided with a large-diameter zoom interlocking gear 22a whose rotation axis coincides with the lens optical axis so as to surround the taking lens 14. The camera body 12 is also provided with a drive motor 16a and a zoom gear train 16 for transmitting the torque of the drive motor 16a to the zoom interlocking gear 22a. The rotation of the drive motor 16a is transmitted to the zoom interlocking gear 22a via the zoom gear train 16 so that the photographing lens 14 is driven forward and backward (zooming) in the optical axis direction.

The camera body 12 includes a barrier plate 20
Has a barrier movement restriction mechanism 18 that locks or releases the barrier plate 20 located at the open position in conjunction with zooming of the photographing lens 14. The barrier movement limiting mechanism 18 includes a unit plate 41 fixed to the camera body 12 adjacent to the photographing lens 14.
have.

The unit plate 41 is fixed to the inside of the front wall 12a of the camera body 12. The unit plate 41 includes an idle gear 22b meshing with the zoom interlocking gear 22a, and an idle gear 22b.
Lock operating gear 24 having a larger diameter than the gear 22b
Is rotatably pivoted. The lock lever 30 is also pivotally attached to the unit plate 41 via a shaft 32,
A positioning projection 42 and a shaft 44 are formed adjacent to the shaft 32 so as to protrude. The lock lever 30 has a lock claw 30b at a free end of the lever body, and a spring hook 3 having an angle different from the lever body by 90 [deg.] On the rotation base.
0a. The lock lever 30 also has a pressed portion 30c that is pressed by the engagement protrusion 26a of the cam member 26 between the spring hook portion 30a and the lock claw 30b in the lever body.

A coil portion of a torsion spring 34 is fitted on the shaft 32, and one end and the other end of the torsion spring 34 are hooked on a spring hook 30a and a shaft 44, respectively. As a result, the lock lever 30 is
In the free state, the spring hook portion 30a is brought into contact with the positioning protrusion 42, and the lock claw 30b is positioned at the lock position. This lock claw 30
b is bent toward the front of the camera so as to protrude from the protruding hole 12c formed in the front wall 12a toward the barrier plate 20 (see FIG. 2). When the lock lever 30 is rotated in the counterclockwise direction and the clockwise direction in FIG. 3, the lock claw 30b is in a lock release position where the lock claw 30b cannot be engaged with the rib 20a. (Shown by a solid line in the figure).

The lock operation gear 24 includes a pressed portion 3
A cam member 26 having an engaging projection 26a for pressing Oc is coaxially pivoted via a shaft 45. As shown in FIG. 4, the lock operation gear 24 has a shaft hole 24 d through which the shaft 45 is inserted. The lock operation gear 24 is coaxial with the shaft hole 24 and has an inner diameter gradually larger than that of the shaft hole 24. It has a cylindrical rotation support step 24c and a spring storage step 24a. The rotation support step 24c is formed with a rotation restricting projection 24b protruding part of the inner circumference toward the center. The rotation restricting projection 24b connects the cam member 26 to
In the clockwise direction (lock direction) and the counterclockwise direction (lock release direction). A spring support hole 24e into which one end of the torsion spring 28 is inserted is formed near the rotation restricting projection 24b in the spring storage step 24a.

The cam member 26 has, at the center thereof, a shaft hole 26b through which the shaft 45 is inserted, and has the engaging projection 26a protruding substantially in the radial direction. This engagement protrusion 26a
When the cam member 26 is coaxially supported by the lock operation gear 24, the length is formed so as not to protrude outward from the operation gear 24. Further, the cam member 26 has, on the side facing the lock operation gear 24, a cylindrical projection 26c that is rotatably fitted to the rotation support step 24c. This cylindrical projection 26c
The rotation restricting projections 24 when fitted to the rotation support step portions 24c.
b has a notch 26b for receiving the same. The notch 26b rotates in a state in which the cam member 26 coaxially supported by the lock operation gear 24 is rotatable by a predetermined angle in the normal and reverse directions with respect to the rotation restricting projection 24b. It is formed so as to leave a predetermined space in the direction (see FIGS. 5 and 6). The cam member 26 further includes
A spring support hole 26d for inserting the other end of the torsion spring 28 is provided on the back surface near the engagement protrusion 26a.

In the cam member 26 having the above configuration, a coil portion is fitted in the spring accommodating step 24a, and one end of the torsion spring 28 is inserted into the spring support hole 24e, and the other end is inserted into the spring support hole 26d. In this state, the notch 26b is aligned with the rotation restricting projection 24b, and the cylindrical projection 26c is fitted into the rotation supporting step 24c. Lock operating gear 24
The cam member 26, which is assembled as described above and pivotally attached to the unit plate 41 via the shaft 45, is always urged by the torsion spring 28 to rotate counterclockwise in FIG. When one end of 26b abuts on the rotation restricting projection 24b, the relative rotation position with respect to the lock operation gear 24 is determined. Therefore, the lock operation gear 2
4 and the cam member 26 are connected by a torsion spring 28 as shown in FIG.
In the counterclockwise direction (lock release direction) of the cam member 2
6 is always rotated integrally while maintaining the state of relative rotation until it is locked by the rotation restricting projection 24b.

In this state, the engaging projection 26a of the cam member 26
On the other hand, when a load larger than the spring force of the torsion spring 28 acts on the cam member 26, the cam member 26 relatively rotates clockwise in FIG. reference). In this case, the cam member 26 is
The rotation is stopped at a position where the other end of 6b comes into contact with the rotation restricting projection 24b.

Here, since the torsion spring 34 is set to have a smaller spring force (rotational urging force) than the torsion spring 28, if the lock lever 30 is in a free state, the lever 30 is turned counterclockwise. To position the lock claw 30b on the movement locus of the rib 20a on the back surface of the barrier plate 20 (see FIG. 5). Lock lever 3
If the pressed portion 30c is pressed in the free state of 0,
The lock lever 30 rotates clockwise, and the lock pawl 30
b is retracted from the movement locus of the rib 20a (see FIG. 5). Further, as shown in FIG. 7, when the pressed portion 30c is pressed down by the cam member 26 that rotates counterclockwise while the lock lever 30 is held at the lock position, the presence of the torsion spring 28 is provided. The cam member 2 is prevented from moving by the pressed portion 30c in a fixed state.
6, the lock operation gear 24 idles.

That is, the rotation restricting projection 24b and the notch 2
6b and the torsion spring 28, the lock operation gear 24
When the rotation resistance applied to the lock lever 30 between the and the cam member 26 is equal to or less than a predetermined value, the cam member 26 is rotated integrally with the lock operation gear 24 to rotate the lock lever 30 in the unlocking direction, When the rotation resistance exceeds a certain value, there is a clutch mechanism that rotates the lock operation gear 24 with respect to the cam member 26 and does not rotate the lock lever 30. Note that in FIG.
A gap is formed between the rib 0a and the rib 20a so that the barrier plate 20 can be slightly moved toward the shielding position in order to turn off the drive switch.

The barrier movement restricting mechanism of the present camera having the above configuration operates as follows. That is, in the non-use state where the taking lens 14 is located at the storage position and the barrier plate 20 is located at the shielding position, the lock operation gear 24 is rotated counterclockwise as shown in FIG. 26
a presses the pressed portion 30c, and locks the lock claw 30b with the rib 2.
It is retracted (positioned at the lock release position) from the movement trajectory 0a. In this state, when the barrier plate 20 is moved toward the open position, a drive switch (not shown) is turned on, the drive motor 16a is driven to rotate, and the photographing lens 14 is extended to the photographing position.

At this time, since the zoom interlocking gear 22a which rotates clockwise in FIG. 3 rotates the lock operation gear 24 clockwise via the idle gear 22b, the engaging projection 26a of the cam member 26 is covered. The pressing portion 30c is released. Therefore, the lock lever 30 is rotated in the counterclockwise direction in FIG. 6 until the spring hook 30a comes into contact with the positioning protrusion 42, and the lock claw 30b is moved to the open position by the rib 20a.
(See FIG. 5). In this locked state, the shooting preparation is completed.

After the photographing is completed, the barrier plate 20
Is slightly moved toward the shielding position, the drive motor 16a is driven to rotate based on the turning off of a drive switch (not shown), and the photographing lens 14 is retracted to the storage position. At this time, since the zoom interlocking gear 22a rotates counterclockwise (see FIG. 3), the lock operation gear 24 is gradually rotated counterclockwise in FIG. 5 via the idle gear 22b. Accordingly, since the engagement projection 26a of the cam member 26 presses the pressed portion 30c, the lock lever 30 rotates clockwise in FIG. 5 against the torsion spring 34, and the lock claw 30b is moved to the open position. The moved rib 20a is retracted from the movement locus (see FIG. 6).

When the photographing lens 14 is driven from the photographing position to the storage position, if the barrier plate 20 is strongly pressed by mistake to close it, the ribs 20a of the barrier plate 20 are moved to the lock claws 30b. It comes into contact and is pressed in the locked position. At this time,
When the photographing lens 14 in the middle of driving reaches the storage position, the engagement protrusion 26a of the cam member 26 moves the pressed portion 3 in a state where the rotation resistance p applied to the lock lever 30 exceeds a certain value.
0c will be pressed. However, the lock operation gear 2
4 and the cam member 26 are connected to the torsion spring 28 as described above.
And so on, the rotation resistance of the engagement protrusion 26 a of the cam member 26 overcomes the rotation urging force of the torsion spring 28, and the lock operation gear 24 is moved relative to the cam member 26. Relative rotation (idling) (see FIG. 7). Therefore, it is necessary to surely prevent a problem that a large load is applied to an interlocking mechanism such as a gear train and a driving system of a photographic lens as in a barrier movement restriction mechanism of a conventional camera, resulting in malfunction or breakage. Can be.

[0024]

As described above, according to the present invention, a large load is imposed on the interlocking mechanism such as the gear train and the driving system of the photographing lens even when an external force is applied due to a user's erroneous operation in the open state of the barrier plate. It is possible to provide a barrier movement restricting mechanism capable of reliably preventing a malfunction that is hung and causes a malfunction or breakage.

[Brief description of the drawings]

FIG. 1 is a partially cutaway front view showing a camera to which a barrier movement restriction mechanism of the present invention is applied.

FIG. 2 is a cross-sectional view of the barrier movement restriction mechanism, taken along line II-II of FIG.

FIG. 3 is an enlarged view showing the barrier movement restriction mechanism.

FIG. 4 is an exploded perspective view showing an enlarged clutch mechanism of the barrier movement restriction mechanism.

FIG. 5 is an enlarged view showing a locked state of a barrier plate of the barrier movement restriction mechanism.

FIG. 6 is an enlarged view showing an unlocked state of a barrier plate of the barrier movement restriction mechanism.

FIG. 7 is an enlarged view showing a state where the lock claw held at the lock position is to be moved to the unlock position in the barrier movement restriction mechanism.

[Description of Signs] 10 Camera 14 Photographing lens 20 Barrier plate 20a Rib (locking portion) 24 Lock actuating gear (rotating member) 24a Spring storage step 24b Rotation restricting projection (locking portion) 24c Rotation support step 26 Cam member (unlocking member) 26a Engagement projection 26b Notch portion 28 Torsion spring (first torsion spring) 30 Lock lever 30a Spring hook portion 30b Lock claw 30c Pressed portion 32 45 Shaft 34 Torsion spring (second torsion spring) ) 42 Positioning protrusion

Claims (4)

(57) [Claims] 1. A camera comprising: a photographing lens capable of moving forward and backward between a photographing position and a storage position; and a barrier plate movable between a shielding position covering the photographing lens located at the storage position and an open position for opening. A lock lever that pivots to a lock position where the barrier plate can be engaged with a lock portion of the barrier plate when the barrier plate is opened; a pivot member that pivots when the photographing lens moves to the storage position; A lock releasing member coaxially mounted on the member and engageable with the lock lever; provided between the rotation member and the lock release member; when the rotation resistance applied to the lock lever is equal to or less than a predetermined value, the lock is released. The unlocking member is rotated integrally with the rotating member to rotate the lock lever in the unlocking direction, and when the rotation resistance exceeds a certain value, the rotating member idles with respect to the unlocking member. Camera barrier movement limiting mechanism comprising the; the lock lever and the clutch mechanism does not rotate Te. 2. A camera body according to claim 1, wherein the rotating member pivots in a locking direction and an unlocking direction by receiving a driving force when the photographing lens moves back and forth between a photographing position and a storage position. And a lock release gear, wherein the unlocking member is a cam member rotatably and coaxially pivotally attached to the lock operation gear. 3. The lock operating gear according to claim 2,
A locking portion that locks the cam member at a relative angle different from each other in the locking direction and the unlocking direction, wherein the lock operating gear and the cam member are provided between the first and second locking members.
A barrier movement restricting mechanism for a camera, which is kept integrally rotated in the unlocking direction by the torsion spring until the cam member is locked by the locking portion, and is always integrally rotated. 4. The lock lever according to claim 3, wherein
The second torsion spring is biased by the torsion spring toward the lock position, and the second torsion spring is set to have a smaller rotational biasing force than the first torsion spring.