JPH0990470A - Barrier movement restricting mechanism for camera - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a barrier movement restricting mechanism capable of surely preventing failure causing faulty actuation and breakage because large load is imposed on a linking mechanism such as a gear train and the driving system of a photographing lens even when external force caused by the misoperation of a user is exerted in a state where a barrier plate is opened. SOLUTION: This mechanism is equipped with a lock lever 30 turning to a lock position where it can engage with the lock part 20a of the barrier plate when the barrier plate is opened; a turning member 24 turning when the photographing lens is moved to a housing position; a lock releasing member 26 pivotally supported to be coaxial with the member 29 and engaged with a lock lever 30; and a clutch mechanism arranged between the members 24 and 26, turning the lock lever in a lock releasing direction when turning resistance applied to the lock lever is equal to or under a fixed value, and idly rotating the member 24 with respect to the member 26 when the turning resistance exceeds the fixed value so that the lock lever 30 may not turn.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a barrier movement limiting mechanism for limiting movement of a barrier plate that protects a taking lens of a camera.

[0002]

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

Therefore, in such a capsule type camera, even if the barrier plate is closed at a stretch from the use state, the barrier plate comes into contact with the photographing lens while the photographing lens is not completely retracted to the storage position.
Therefore, it is necessary to have a mechanism for locking the barrier plate, which has been slightly moved toward the shielding position to drive the lens driving motor, until the photographing lens is completely retracted. Such a barrier movement limiting mechanism is usually
It is driven by using the driving force when the shooting lens is extended and extended.

This barrier movement limiting mechanism is provided with a lock claw that moves the barrier plate to a position where it can be locked in the open position when the barrier plate is moved to the open position, in conjunction with the extension of the taking lens. There is. When the photographing lens is retracted, the lock claw receives a driving force for advancing and retracting the photographing lens via an interlocking mechanism such as a gear train, and is moved to an unlocked position in a direction opposite to the lock position. In such a barrier movement limiting mechanism, for example, when the photographing lens is being driven from the photographing position toward the storage position and is erroneously pressed to close the barrier plate, the barrier plate engages with the lock claw. This will be held in the locked position. In this state, when the taking lens in the middle of driving reaches the storage position, the interlocking mechanism such as the gear train forcibly applies force to the lock pawl in the fixed state. Therefore, a large load is applied to the interlocking mechanism and the drive system of the taking lens, which may cause malfunction or damage.

[0005]

SUMMARY OF THE INVENTION The present invention is based on the above problems in the barrier movement limiting mechanism, and even when an external force is applied by a user's erroneous operation in the opened state of the barrier plate, the interlocking mechanism such as a gear train or the drive system of the taking lens. It is an object of the present invention to provide a barrier movement limiting mechanism capable of reliably preventing a problem that a large load is applied to the device and causes malfunction or damage.

[0006]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention is directed to a photographing lens that can be moved forward and backward between a photographing position and a storage position; and a moving position between a shielding position that covers the photographing lens located at the storage position and an open position that opens. In a camera having a movable barrier plate, when the barrier plate is opened, a lock lever that rotates to a lock position that can engage with a lock portion of the barrier plate; A rotating member that moves; a lock releasing member that is pivotally mounted coaxially to the rotating member and that is engageable with the lock lever; a rotating member that is provided between the rotating member and the lock releasing member and that is applied to the lock lever. When the dynamic resistance is below a certain value, the lock release member is rotated together with the rotating member to rotate the lock lever in the unlocking direction, and when the rotation resistance exceeds the certain value, the rotation unit 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 a lock operating gear pivotally attached to the camera body, which is rotated in a locking direction and an unlocking direction by receiving a driving force when the photographing lens advances and retracts between a photographing position and a storage position. The lock releasing member may be a cam member coaxially pivotally attached to the lock actuating gear so as to be relatively rotatable. The lock actuation gear includes a locking portion that locks the cam member at different relative angles in the lock direction and the lock release direction, respectively, and the lock operation gear and the cam member are provided between the first and second lock actuating gears. With the torsion spring,
It is desirable that the cam member is kept in a state of being relatively rotated in the unlocking direction until it is locked by the locking portion, and is always rotated integrally.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described below with reference to illustrated embodiments. FIG. 1 is a front view showing a state in which a barrier plate of a so-called capsule type camera to which the present invention is applied is opened. When the barrier plate 20 covering the photographing lens 14 in the unused state is opened, the camera 10
A drive switch (not shown) is turned on, and based on this, the photographing lens 14 is extended to be in a photographing ready state. In this state, if the barrier plate 20 is slightly moved in the direction to cover the taking lens 14, the drive switch is turned off, and the taking lens 14 is retracted to the storage position based on this.

The camera 10 has the taking lens 14, the strobe 9 and a finder window 17 on a front wall 12a of a camera body 12, and a shutter button 8 on an upper surface. Further, guide grooves 12b extending in the direction orthogonal to the lens optical axis of the taking lens 14 (the left-right direction of the body 12) are provided above and below the front wall 12a. This guide groove 12
In b, the barrier plate 20 is movable in a direction orthogonal to the lens optical axis of the taking lens 14, that is, a shielding position for covering the taking lens 14 retracted to the storage position and an open position for opening the taking lens 14. Is movably fitted in. The barrier plate 20 is compared by a click stop mechanism (not shown) at the open position and the shield position so that a force larger than a predetermined value is required when moving the barrier plate 20 from the open position to the shield position or from the shield position to the open position. It is locked with a light force. The barrier plate 20 has a rib (lock portion) 20a on the back surface thereof that extends 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 optical axis of the lens 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 that transmits the rotational force 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 taking lens 14 is driven forward and backward (zooming) in the optical axis direction.

The camera body 12 includes a barrier plate 20.
A barrier movement limiting mechanism 18 that locks or releases the barrier plate 20 located at the open position in conjunction with zooming of the taking lens 14 is provided on the side where is located. The barrier movement limiting mechanism 18 is a unit plate 41 fixed to the camera body 12 adjacent to the taking lens 14.
have.

The unit plate 41 is fixed to the inner surface of the front wall 12a of the camera body 12. The unit plate 41 has an idle gear 22b meshing with the zoom interlocking gear 22a and an idle gear 22b.
Locking gear 24 having a larger diameter than the gear 22b meshing with
Is rotatably pivoted. A lock lever 30 is pivotally attached to the unit plate 41 via a shaft 32,
A positioning protrusion 42 and a shaft 44 are formed so as to be adjacent to the shaft 32. The lock lever 30 has a lock claw 30b at the free end of the lever body, and a spring hook portion 3 having a different angle of 90 ° with respect to the lever body at the rotation base.
It has 0a. The lock lever 30 also has a pressed portion 30c, which is pressed by the engagement protrusion 26a of the cam member 26, between the spring hook portion 30a and the lock pawl 30b in the lever body.

The coil portion of the torsion spring 34 is fitted on the shaft 32, and one end and the other end of the torsion spring 34 are hooked on the spring hooking portion 30a and the shaft 44, respectively. This causes the lock lever 30 to move to the position shown in FIG.
In the free state, the spring hooking portion 30a is brought into contact with the positioning protrusion 42 to position the lock claw 30b at the lock position. This lock claw 30
b is bent toward the front of the camera so as to project toward the barrier plate 20 side from the projecting hole 12c formed in the front wall 12a (see FIG. 2). The lock claw 30b is in a lock release position that does not engage with a lock position (shown by a chain double-dashed line in the figure) that can engage with the rib 20a when the lock lever 30 rotates in the counterclockwise and clockwise directions in FIG. (Shown by the solid line in the figure).

The lock actuating gear 24 includes a pressed portion 3
A cam member 26 having an engagement protrusion 26a for pressing 0c is coaxially attached via a shaft 45. As shown in FIG. 4, the lock actuating gear 24 has a shaft hole 24d through which the shaft 45 is inserted, as a center, and is coaxial with the shaft hole 24, and the inner diameter thereof is made larger stepwise than the shaft hole 24. It has a cylindrical rotation support step portion 24c and a spring storage step portion 24a. The rotation supporting step portion 24c is formed with a rotation restricting protrusion 24b which is formed by projecting a part of the inner circumference toward the center. The rotation restricting protrusion 24b is provided on the cam member 26 as shown in FIG.
Locking portions that lock at different relative angles in each of the clockwise direction (locking direction) and the counterclockwise direction (lock releasing direction). Further, a spring support hole 24e into which one end of the torsion spring 28 is inserted is formed near the rotation restricting protrusion 24b in the spring storage step portion 24a.

The cam member 26 has a shaft hole 26b through which the shaft 45 is inserted, as a center, and the engagement protrusion 26a which is projected in a substantially radial direction. The engagement protrusion 26a is
When the cam member 26 is coaxially supported by the lock operating gear 24, the cam member 26 is formed to have a length that does not project to the outer peripheral side from the operating gear 24. Further, the cam member 26 has, on the side facing the lock actuating gear 24, a cylindrical protrusion 26c that is rotatably fitted to the rotation support step 24c. This cylindrical protrusion 26c
Is a rotation restricting protrusion 24 when fitted to the rotation supporting step portion 24c.
It has a notch 26b for receiving b. The cutout portion 26b is rotated in a state in which the rotation restricting protrusion 24b is received so that the cam member 26 coaxially supported by the lock actuating gear 24 can rotate forward and backward by a predetermined angle with respect to the rotation restricting protrusion 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 into which the other end of the torsion spring 28 is inserted is provided on the back surface near the engagement protrusion 26a.

In the cam member 26 having these configurations, the coil portion is fitted in the spring accommodating step portion 24a and one end portion thereof is inserted into the spring supporting hole 24e, and the other end portion thereof is inserted into the spring supporting hole 26d. In this state, the notch 26b is aligned with the rotation restricting protrusion 24b, and the cylindrical protrusion 26c can be fitted to the rotation supporting step 24c. Locking gear 24
The cam member 26 assembled in this manner and pivotally attached to the unit plate 41 via the shaft 45 is always urged to rotate counterclockwise in FIG. 3 by the torsion spring 28. The relative rotation position with respect to the lock actuating gear 24 is determined by contacting one end of 26b with the rotation restricting protrusion 24b. Therefore, the lock operating gear 2
4 and the cam member 26 by means of a torsion spring 28.
In the counterclockwise direction (lock release direction) of the cam member 2
6 is held in the state of being relatively rotated until it is locked by the rotation restricting protrusion 24b, and is always integrally rotated.

In this state, the engaging projection 26a of the cam member 26
On the other hand, when a load larger than the spring force acts against the spring force of the torsion spring 28, the cam member 26 relatively rotates in the clockwise direction of FIG. reference). In this case, the cam member 26 has the cutout 2
The rotation is stopped at the position where the other end of 6b comes into contact with the rotation restricting protrusion 24b.

Since the torsion spring 34 is set to have a spring force (rotational biasing force) smaller than that of the torsion spring 28, if the lock lever 30 is in the free state, the lever 30 is rotated counterclockwise. Then, the lock claw 30b is positioned on the movement locus of the rib 20a on the rear surface of the barrier plate 20 (see FIG. 5). Also, the 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 claw 30
b is retracted from the movement trajectory of the rib 20a (see FIG. 5). Further, as shown in FIG. 7, when the pressed portion 30c is pushed down by the cam member 26 rotating counterclockwise with the lock lever 30 held in the lock position, the presence of the torsion spring 28 is present. By the cam member 2 that is prevented from moving by the pressed portion 30c in the fixed state.
6, the lock operating gear 24 idles.

That is, the rotation restricting protrusion 24b and the notch 2
6b and the torsion spring 28 allow the lock operating gear 24
Between the cam member 26 and the cam member 26, when the rotation resistance applied to the lock lever 30 is less than a certain value, the cam member 26 is rotated integrally with the lock actuating gear 24 to rotate the lock lever 30 in the unlocking direction. There is a clutch mechanism in which the lock actuating gear 24 idles with respect to the cam member 26 and the lock lever 30 does not rotate when the rotation resistance exceeds a certain value. In FIG. 5, the lock claw 3
A gap is formed between 0b and the rib 20a so that the barrier plate 20 can be slightly moved toward the shield position to turn off the drive switch.

The barrier movement limiting mechanism of the present camera having the above structure operates as follows. That is, in the non-use state in which the taking lens 14 is located at the storage position and the barrier plate 20 is located at the blocking position, the lock actuating gear 24 is rotated counterclockwise as shown in FIG. 26
a presses the pressed portion 30c, and the lock claw 30b is attached to the rib 2
It is retracted (positioned at the lock release position) from the movement trajectory of 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 rotationally driven, and the photographing lens 14 is extended to the photographing position.

At this time, the zoom interlocking gear 22a which rotates clockwise in FIG. 3 rotates the lock operating gear 24 clockwise through the idle gear 22b, so that the engagement projection 26a of the cam member 26 is covered. The pressing portion 30c is released. Therefore, the lock lever 30 rotates counterclockwise in FIG. 6 until the spring hooking portion 30a comes into contact with the positioning protrusion 42, and the lock claw 30b moves to the open position of the rib 20a.
It is positioned on the movement locus of (see FIG. 5). In this locked state, shooting preparation is completed.

After the photographing is completed, the barrier plate 20
When is slightly moved toward the shield position, the drive motor (not shown) is turned off to drive the drive motor 16a to rotate, and the taking lens 14 is retracted to the storage position. At this time, since the zoom interlocking gear 22a rotates counterclockwise (see FIG. 3), the lock actuating gear 24 is gradually rotated counterclockwise in FIG. 5 via the idle gear 22b. Therefore, since the engagement protrusion 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 rib 20a that has moved is retracted from the movement path (see FIG. 6).

Further, for example, when the photographing lens 14 is being driven from the photographing position toward the storage position, if the barrier plate 20 is erroneously strongly pressed to close it, the rib 20a of the barrier plate 20 is attached to the lock claw 30b. It abuts and presses it in the locked position. At this time,
When the photographic lens 14 in the middle of driving reaches the storage position, the engagement projection 26a of the cam member 26 pushes the pressed portion 3 in a state in which the rotational resistance p applied to the lock lever 30 exceeds a certain value.
0c will be pressed. However, the lock operating gear 2
4 and the cam member 26, as described above, the torsion spring 28
And the like, the rotation resistance of the engagement protrusion 26a of the cam member 26 overcomes the rotation urging force of the torsion spring 28, and the lock actuation gear 24 with respect to the cam member 26. Relative rotation (idling) is performed (see FIG. 7). Therefore, it is necessary to surely prevent the malfunction that is caused by the heavy load on the interlocking mechanism such as the gear train and the driving system of the photographing lens, which is caused by the barrier movement limiting mechanism of the conventional camera and causes the malfunction or the damage. You can

[0024]

As described above, according to the present invention, even when an external force is applied by a user's erroneous operation when the barrier plate is open, a large load is applied to the interlocking mechanism such as the gear train and the drive system of the photographing lens. It is possible to provide a barrier movement restricting mechanism that can reliably prevent a malfunction that may result in malfunction or damage.

[Brief description of drawings]

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

FIG. 2 is a sectional view taken along line II-II in FIG. 1, showing the barrier movement limiting mechanism.

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

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

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

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

FIG. 7 is an enlarged view showing a state when the lock claw held in the lock position is being moved to the lock release position in the barrier movement limiting mechanism.

[Explanation of symbols]

 10 Camera 14 Photographic Lens 20 Barrier Plate 20a Rib (Lock Part) 24 Lock Operating Gear (Rotating Member) 24a Spring Storage Step Part 24b Rotation Restricting Protrusion (Locking Part) 24c Rotation Supporting Step Part 26 Cam Member (Unlock) Member) 26a Engagement protrusion 26b Notch portion 28 Torsion spring (first torsion spring) 30 Lock lever 30a Spring hooking portion 30b Lock claw 30c Pressed portion 32 45 Shaft 34 Torsion spring (second torsion spring) 42 Positioning protrusion

Claims (4)

[Claims] 1. A camera comprising: a photographing lens that can be moved back and forth between a photographing position and a storage position; and a barrier plate that can be moved between a shielding position that covers the photographing lens located at the storage position and an open position that opens. A lock lever that rotates when the barrier plate is opened to a lock position that is engageable with a lock portion of the barrier plate; a rotation member that rotates when the photographing lens moves to a storage position; A lock releasing member pivotally mounted coaxially to the member and engageable with the lock lever; provided between the rotating member and the lock releasing member, and when the rotation resistance applied to the lock lever is below a certain value, the lock When the release member rotates together 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 lock releasing member. Camera barrier movement limiting mechanism comprising the; the lock lever and the clutch mechanism does not rotate Te. 2. The rotating member according to claim 1, wherein the rotating member is pivotally attached to a camera body, which is rotated in a locking direction and an unlocking direction by receiving a driving force when the photographing lens advances and retracts between a photographing position and a storage position. A barrier movement limiting mechanism for a camera, which is a locked lock gear, and a lock release member is a cam member pivotally mounted on the lock lock gear so as to be relatively rotatable. 3. The lock operating gear according to claim 2,
A locking member for locking the cam member at relative angles different from each other in the locking direction and the unlocking direction, respectively, and the lock actuation gear and the cam member are provided between the first and second locking operation gears;
The barrier movement limiting mechanism of the camera, which is kept rotated by the torsion spring of the cam member in the unlocking direction until it is locked by the locking portion and is always rotated integrally. 4. The lock lever according to claim 3, wherein the lock lever is the second.
The biasing force of the second torsion spring is set to be smaller than that of the first torsion spring by a torsion spring of the first torsion spring.