JPH0486635A - Device for preventing malfunction of camera - Google Patents

Abstract

PURPOSE:To prevent an exposure from unwillingly executed by restricting a lever in a shutter blade open/close mechanism in such a way that it is not actuated when a photographic lens is in non photographing state. CONSTITUTION:On a camera in which a photographic lens barrel 1 incorporating a shutter blade 6 is made to move between a photographing position and a non photographing position, a driving means 8 to actuate to open/close the shutter blade 6, locking means 40 which is displaced according to the movement of the photographic lens barrel 1 and occupies the actuation stopping position of the driving means 8 when the photographic lens barrel 1 is in the non photographing position are provided. And the photographic lens barrel 1 is locked on one part of the shutter blade open/close mechanism which is the driving means 8 by the movement of the photographic lens barrel 1 to the non photographing position, and the shutter blade 6 is locked lest it should open. Thus, the shutter blade is prevented from opening by vibration or impact, so that a film is not unwillingly exposed.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention is a camera malfunction prevention device, specifically, a device for preventing the shutter from accidentally operating due to external vibrations or shocks when the camera is not in use. This invention relates to a malfunction prevention device.

[Prior Art] A camera that holds a photographic lens, has a built-in shutter blade, and has a photographic lens barrel that moves between a photographing position and a non-photographing position is disclosed in Japanese Patent Laid-Open No. 63-23138, etc. It is well known by

This camera has a drive mechanism disposed within the camera body that opens and closes the shutter blade, and when the camera is not in use, the lens barrel returns to a reset position next to the camera body.

In addition, it is a camera with a collapsible lens barrel, and the lens barrel collapsible mechanism is located on the camera body.
Furthermore, cameras in which the shutter unit is retracted and extended together with the lens barrel are also well known.

[Problems to be Solved by the Invention] Incidentally, in the camera disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 63-23138 and the above-mentioned retractable camera, the shutter blade opening/closing mechanism is not connected to the lens barrel moving mechanism or the retractable camera. Because it is independent from the shutter mechanism, if vibration or impact is applied to the camera when the camera is not in use or when it is being carried around, the shutter blade opening/closing mechanism may become unbalanced, and the sector blade may inadvertently open. The problem is that the camera may open and expose the camera even when there is no intention to take a picture.

Next, to explain this problem in a little more detail with reference to FIG. 2 of the attached drawings, the shutter opening/closing lever 8 is
The support arm 10, which is swingably held by the support arm 10, is rotatably supported at its base by a support shaft 16, and when the camera is not in operation, the attracted part 18 is attracted to the electromagnetic magnet 17 by the tightening elasticity of the coil spring 15. They are becoming more spaced apart.

However, if an external shock is applied to the camera in this state, the support arm 10 becomes unbalanced with respect to the support shaft 16, and the arm 10 resists the elasticity of the spring 15 while the attracted part 18 becomes an electromagnetic magnet. Until it comes into contact with 17,
It rotates counterclockwise around the support shaft 16. As a result, the lever 8 rotates clockwise about its AE drive pin 9, and the sector opening/closing pin 7 moves away from the lens optical axis, causing the shutter blade 6 to open and release the film. You will be exposed.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a camera malfunction prevention device that eliminates the drawback that the shutter blade opens due to vibration or impact and the film is inadvertently exposed.

[Means and effects for solving the problem] The camera malfunction prevention device according to the present invention is applicable to a camera in which a camera lens barrel having a built-in shutter blade is moved between a photographing position and a non-photographing position. , a driving means for opening and closing the shutter blade; and a driving means configured to be displaced in accordance with the movement of the photographing lens barrel, and occupy a position where the operation of the driving means is inhibited when the photographing lens barrel is in a non-photographing position. and a locking means that locks a part of the shutter blade opening/closing mechanism, which is the driving means, by moving the photographing lens barrel to a non-photographing position, Lock the opening/closing mechanism to prevent the shutter blade from opening.

〔Example〕

The present invention will be explained below with reference to illustrated embodiments.

FIG. 1 is a perspective view of a camera malfunction prevention device showing a first embodiment of the present invention, and is shown together with a camera exposure/focus adjustment device, and FIG. 2 is a perspective view of the device shown in FIG. 1. FIG.

The photographic lens 1a is held within a lens barrel 1 fixed to a lens frame 2, and this lens frame 2 holds the photographic lens 1a.
The lens 1a is held so as to be movable along the optical axis direction from a close focus position to an infinity photographing position and a non-photographing reset position. That is, this lens frame 2 has a protruding engaging portion 2a that fits into a guide groove 3a formed in a rotation stopper 3 provided on a stationary member at a part of the negative side edge of the lens frame 2.
Also, a portion of the other side edge opposite to this is slidably fitted into a guide hole formed in a stationary member (not shown).
Fork-shaped portions 2b each having guide pins 2c and 2c' parallel to the optical axis are provided, and the photographic lens barrel 1
is designed to guide the optical axis in the direction of the optical axis. Also, built into this lens barrel is a shutter blade 6 consisting of two sector blades, 1 and 2, which are arranged on the lens frame 2 and a vario-type shutter. A pin 7 for opening/closing the sector is fitted into the opening/closing hole 6a.

Further, the fully open position and the fully closed position of the shutter are regulated by a stopper (not shown). This sector opening/closing pin 7 is fixed to the tip of one arm 8a of the opening/closing lever 8, and the downwardly bent tip of the other arm of the lever 8 has a drive for automatic exposure (hereinafter referred to as AE). pin 9
is fixed.

A locking pin 40 that extends upward from one arm 8a of the opening/closing lever 8 is fixed to the lens frame 2 near the hole through which the sector opening/closing pin 7 passes.

The middle fulcrum of the lever 8 is rotatably supported by a support shaft 11 fixed to a bent portion of a support arm 1o whose base is rotatably attached to a support shaft 16. This lever 8
An attracted part 12 that is attracted by an electromagnetic magnet 13 is fixed to the bent part near the tip of the other arm. The lever 8 is given the ability to rotate clockwise about the support shaft 11 by a spring 14 applied to the bent portion of the other arm, and the support arm 10 is also applied to the distal end thereof. The spring 15 provides a clockwise rotational habit about the support shaft 16. moreover,
An attracted part 18 that is attracted by an electromagnetic magnet 17 is fixed to the tip of the support arm 10 whose base is rotatably supported by a support shaft 16 fixed to an immovable member. Further, at the base of the AE drive bin 9 fixed to the lever 8, a contact portion 9a (second
(see figure) is formed.

On the other hand, the rotational driving force of the motor M, which serves as a driving source for adjusting exposure and focus of the camera, is transmitted to a differential gear mechanism. That is, the output gear 20 fixed to the output shaft of the motor M meshes with a large-diameter gear 21, and a small-diameter gear 212 is integrally formed with the boss portion of this gear 21. A large diameter gear 22 is rotatably disposed around the section. The gear 21a is formed to protrude from the front side of the large-diameter gear 22, and this gear 218 has three support shafts 22a, 22a arranged at equal angles on the front side of the large-diameter gear 22. ,
22a rotatably supported planetary gear 23.23.
23 are engaged.

These three planetary gears 23, 23, 23 mesh with the internal teeth 24a of the internal gear 24, and the AE cam gear 30 meshes with the external teeth 24b formed on the outer periphery of the internal gear 24. .

In the driving force transmission means constituted by the differential gear mechanism configured in this way, the rotation of the large diameter gear 21 is controlled by the rotation of the small diameter gear 2.
It is transmitted to the planetary gear 23 via 1a. Here, when the rotation of the large-diameter gear 22 is restricted, the planetary gear 23 rotates around the support shaft 22a, thereby causing the internal gear 24 to rotate. On the other hand, when the rotation of the internal gear 24 is restrained, the planetary gear 23 does not rotate around the support shaft 22H, and the internal teeth 24 of the internal gear 24
The small diameter gear 21a is used as a sun gear and revolves around the small diameter gear 21a along the direction a. Therefore, the support shaft 22a also moves with the movement of the planetary gear 23, and as a result, the large diameter gear 22
Or it will rotate.

On the back surface of the AE cam gear 30, an AE cam 30a consisting of a closed-loop endless groove into which the drive pin 9 is fitted as a cam follower is formed.
A locking portion 30b is formed in a portion of the cam groove 30a. Further, a reflective pattern 31 for regulating the reset position is formed on the front surface of the AE cam gear 30, and a photoreflector 32 is disposed opposite to the reflective pattern 31 for regulating the reset position. Also, AE cam gear 30
An AF cam gear 33 is rotatably provided on a support shaft 39 that rotatably supports the AF cam gear 33 . This AF cam gear 33 consists of a front gear 33a with thin teeth located at the front and a rear gear 33b with thick teeth located at the rear thereof.The front gear 33a is a large part of the differential gear mechanism described above. It meshes with the diameter gear 22, and on the front side of this gear 33a,
AF cam stopper 34 is attached. Also,
The rear gear 33b of this AF cam gear 33 has an AF
The upper gear 5 meshes with the protrusion 2d provided inside the fork-shaped portion 2b of the lens frame 2.
, 2e, a part of it is sandwiched. This AF upper gear 5 has four levels of subject distance, for example, 1m, 3m, 5m, and ■ from the first stage to the fourth stage, as shown in the expanded view in Figure 3 on both sides. Step cam 35a for AF drive divided into steps in order to control to the reset position
~35e are formed. Also, this AF upper gear -5
, a reset position regulating reflective pattern 36 for detecting the rotational position is formed on a part of the circumferential surface of the boss portion thereof, and a photoreflector 37 is arranged opposite to this reset position regulating reflective pattern 36. ing.

Next, the operation of the exposure/focus adjustment device configured as described above and the device of the present invention will be explained.

First, when the camera is not in use, the AF gear 35
The lens barrel 1 is moved back in the optical axis direction by the reset cam 35e of the stepped cam, and is at the reset position which is the initial position, and the locking pin 40 is engaged with the opening/closing lever 8 as shown in FIG. 1 is engaged on the arm 8a. Therefore, even if shock or vibration is applied to the camera, the opening/closing lever 8
Since the operation of the shutter blade 6 is restricted, the sector opening/closing mechanism is prevented from operating and the shutter blade 6 is prevented from opening inadvertently.

When taking pictures, when the motor M starts rotating, the output gear 20 rotates, and along with this, the large diameter gear 21
．． A small diameter gear 21a rotates in one direction. The rotation of this gear 21 is controlled by a small diameter gear 218. Planetary gear 23.
The signal is transmitted to the internal teeth 24a of the internal gear 24 via 23 and 23. At this time, the rotation of the large-diameter gear 22 is prevented by a large load placed on the AF gear 35 having stepped cams 35a to 35e in the focusing mechanism, the lens frame 2 holding the photographic lens, and the like. Therefore, gear 21 with a large diameter
The rotation of the small diameter gear 21a is entirely carried out by the internal gear 2.
The rotation of the internal gear 24 is transmitted to the AE cam gear 30.

When the AE cam gear 30 rotates, the lever 8 is lifted up by the cam 30a at the initial stage, and the attracted part 18.12 is attracted to the electromagnetic magnet 17.13. By the subsequent rotation, an automatic exposure value is determined by an exposure device (not shown), and the drive pin 9 reaches the locking portion 30b of the cam 30a. Then, since the rotation of the AE cam gear 30 is stopped, the large diameter gear 22 rotates, and the AF gear 35 is connected to the AF gear 35 via the gear 33a and the rear gear 33b.
rotates.

When this rotates, the lens barrel 1 that was at the reset position is extended by the step cam 35e, so the locking pin 4
0 comes off from the first arm 8a of the opening/closing lever 8 and releases the restraint. Then, AF is performed using a signal from a distance measuring device (not shown).
Rotation of the gear 35 is regulated, and the lens barrel 1 is placed at an optimal AF position by step cams 35a to 35d.

Thereafter, the electromagnetic magnet 13 is demagnetized, the opening/closing lever 8 rotates clockwise around the support shaft 11 due to the elasticity of the spring 14, the opening/closing pin 7 moves upward, and the shutter blade 6
opens. When the proper exposure time has elapsed, the electromagnetic magnet 17 is demagnetized, the support arm 10 rotates clockwise around the support shaft 16 due to the elasticity of the spring 15, the opening/closing lever 8 is pushed down by the support shaft 11, and the AE Drive pin 9
The shutter blade 6 is rotated counterclockwise using the opening/closing pin 7 as a fulcrum and the shutter blade 6 is closed.

After the exposure is completed, the AF cam gear 33 further rotates the AF gear 35, and the stepped cam 35e moves the lens barrel 1 back to the reset position. Then, the locking pin 40 of the lens frame 2 comes into contact with one arm 8a of the opening/closing lever 8, so that the lever 8 becomes locked again.

In this manner, the malfunction prevention device according to the first embodiment of the present invention, as shown in FIG.
The opening/closing lever 8 is allowed to operate by disengaging it, and after the camera has completed the shooting operation, the lens barrel 1 is returned to the reset position and locked as shown in Fig. 4 (B). Since the pin 40 is engaged with the first arm 8a to restrict the operation of the sector opening/closing lever 8, the shutter blade 6 will not open involuntarily even if an external impact is applied when the camera is not in use. Prevented.

5 to 8 (A) and (B) show a second embodiment of the present invention. In this second embodiment, the present invention is applied to a retractable camera, and a shutter unit 50 (see FIG. As shown in FIG. 7, when the camera is not in use, the lens barrel 41 is stored in the retracted position, which is the reset position within the camera body (not shown), and when the camera is not in use. Sometimes it protrudes from within the camera body toward the subject 60, and focusing is performed between the photographing position and the closest photographing position.

Note that the reference numeral 61 indicates a photographic film loaded into the camera body.

The lens barrel 41 that moves in this manner performs a focusing operation when it is moved to the collapsing position and the photographing position by the drive motor NIO, as shown in FIG. That is, at the lower part of the rear end of the lens barrel 41, there is a drive block 4.
The block body 41b is provided with a female threaded hole extending in the optical axis direction. A feed screw shaft 42 is screwed into this female threaded hole.
A drive gear 42a is fixed to the rear end of the motor M. output gear-43
They are engaged.

Further, the output gear 43 is engaged with a photointerrupter driving gear 44, and the slit disk 45 of the AF photointerrupter 47 is rotated by the gear 44. The photointerrupter 47 is well known and has a light emitting part and a light receiving part, the light beam from the light emitting part is cut by the slit disk 45, and the light passing through the slit is received by the light receiving part. The photo ink club 47 outputs a pulse signal for detecting the rotation angle of the motor.

On the other hand, the driving block body 41b of the lens barrel 41
A protruding piece 41c for preventing rotation is integrally provided at the upper part on the opposite side. This protruding piece 41c has a guide elongated hole 41d, and a rotation stopper/guide shaft 48 fixed to the camera body is inserted into the elongated hole 41d. Further, the tip of the protruding piece 41c has a normally closed type A.
A protruding piece 41e for turning off the F switch 49 is formed. The AF switch 49 outputs a signal for detecting the collapsed position and starting pulse counting for focusing.

As shown in FIG. 6, the shutter unit 50 is composed of two shutter blades 46a and 46b of a vario-type shutter arranged behind the photographing lens 41a and an opening/closing mechanism for the blades.

That is, the bases of both shutter blades 46a, 46b are rotatably supported by immovable support shafts 51a, 51b, respectively, and the bases of the shutter blades 46a, 46b are rotatably supported by fixed support shafts 51a, 51b, respectively. Opening/closing pin 5 in the overlapped common through hole
2 is inserted.

The opening/closing bin 52 is implanted at the end of one arm 54H of the sector lever 54, which is swingably supported by a stationary support shaft 53 at its middle fulcrum. This sector lever 54 is connected to the other arm 54.
Due to the tightening elasticity of the coil spring 55 applied to b, the support shaft 5
3 in the clockwise direction, and the shutter blade 46a
, 46b, and rotation due to this behavior is prevented by the sector lever 54 coming into contact with the stopper pin 56 when the shutter blades 46a, 46b are in the closed position.

A drive pin 57 is installed at the tip of the other arm 54b of the sector lever 54, and this pin 57 is fitted into a movable iron core 58a of an electromagnetic plunger 58 for opening and closing the shutter. In this electromagnetic plunger 58, when the sector lever 54 is in contact with the stopper pin 56, the movable iron core 58a is separated from the fixed iron core, but when a current flows through the plunger 58, the movable iron core 58a becomes electromagnetic. The force attracts the fixed iron core and rotates the sector lever 54 counterclockwise.

Further, an AE photo interrupter 59 is attached to the tip of one of the shutter blades 46b.
The shutter blades 6b are disposed to sandwich the tip of the shutter blades 46a and 46b, and detect movement of the shutter blades 46a and 46b.

In this embodiment, as shown in FIG. 8(B), when the lens barrel 41 is in the retracted position, the sector lever 54 engages with the locking pin 63 fixed to the immovable member 62 of the camera. Movements are now restricted. That is,
When the lens mirror @41 is in the retracted position, the sector lever 5
The immovable locking pin 6 is attached to the opposite side of the one arm 54a of the fourth arm 54a from the side that abuts the stopper pin 56.
The locking pin 63 restricts the movement of the sector lever 54 while the lens barrel 41 moves from the collapsed position to the photographing position (■). It has become so.

Next, the operation of this embodiment configured as described above will be explained. Before the shutter is released, the lens barrel 41 is in the retracted position and the AF switch 49 is turned off.

In this state, when the release button (not shown) is pressed, the motor M is activated. Then, the feed screw shaft 42 rotates via the output gear 43 and the drive gear 42a. When this rotates, the lens barrel 41 starts to extend toward the subject 60 by the drive block 41b. When this feeding is started, A
The F switch 49 is turned on when the protruding piece 41e is separated. When this is turned on, the AF photo interrupter 47 counts the number of slits on the slit disk from that point on.1. The motor Mo is stopped when the number of pulses required to feed out the amount corresponding to the shooting distance has been counted based on distance measurement data measured in advance. Focusing ends with this. Further, in this focusing operation, when the lens barrel 41 reaches the photographing position, one arm 54a of the sector lever 54 separates from the locking pin 63, so that the lever 54 is released from being restrained.

Next, a current is supplied to the electromagnetic plunger 58. Then, the movable iron core 58a is attracted to the fixed iron core, and the sector lever 54 rotates counterclockwise while resisting the elasticity of the closing spring 55. This also charges the spring 55. When the sector lever 54 rotates counterclockwise, the opening/closing pin 52 also rotates counterclockwise, so the shutter blades 46a, 46b move in the opening direction. When the shutter blades 46a and 46b begin to open, A
E photointerrupter 59 is turned on.

From this point on, exposure is started based on the photometric data measured in advance, and when the time for proper exposure has elapsed, the plunger 58 is turned off. When the plunger 58 is turned off, the adhesion force between the movable iron core 58a and the fixed iron core disappears, so the sector lever 54 returns to rotation in the clockwise direction due to the tightening elasticity of the charged closing spring 55 until it comes into contact with the stopper pin 56. . As a result, the opening/closing pin 52 closes the shutter blades 46a, 46b.

When this shutter blade closes, the AE photo ink club is turned off. Then motor M.

is driven in reverse. Then, the lens barrel 41 starts retracting in the collapsing direction by the feed screw shaft 42. When the lens barrel 41 passes the flash photography position, the locking pin 63 comes into contact with the side surface of the first arm 54a of the sector lever 54, so that the operation of the sector lever 54 is restricted again. When the lens barrel 41 is further retracted and reaches the retracted position, the AF switch 49 is turned off by the projection 41e. At this point, the rotation of the motor Mo is stopped and the photographing is completed.

In this embodiment, as shown in FIG. 8(A), when the camera is in the photographing state, the locking pin 63 is disengaged from the first arm 54a of the sector lever 54, and the sector lever 54 is moved. When the lens barrel 41 returns to the retracted position within the camera body, which is the reset position, the locking pin 63 is re-engaged as shown in No. 8(B). 1 arm 54a, and the sector lever 54
Since the sector lever 54 cannot be rotated by the locking pin 63 even if vibration or impact is applied from the outside when the camera is not in use, the shutter blades 46a and 46b may open unexpectedly. Problems such as being exposed to light will be resolved.

Without the locking pin 63, the shutter blade would open when an impact force stronger than the closing spring 55 is applied from the outside due to the unbalance of the sector lever rotation system. With this configuration, the above-mentioned drawbacks are eliminated.

In the above embodiment, the locking pin 63 is provided to restrain the sector lever, but the same effect can be obtained even if the movable iron core 58a of the electromagnetic plunger 58 is locked. Needless to say.

[Effects of the Invention] As described above, according to the present invention, the lever in the sector opening/closing mechanism that drives the shutter blade to open and close is restrained so that it is inactive when the photographic lens is not in the photographing state, and Since the restraint is released when the camera is displaced from the outside, the sector opening/closing mechanism will not operate even if a strong impact force such as vibration or shock is applied to the camera from the outside, and the shutter blade will open/close unexpectedly. Exposure to light is prevented. Therefore, accidents such as unexpected double exposure in this type of camera can be prevented.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a main part of a malfunction prevention device for a camera showing a first embodiment of the present invention, FIG. 2 is a front view of a main part of a malfunction prevention device of the first embodiment, and FIG. 4(A) and 4(B) show the photographing position and non-photographing position of the lens barrel in the malfunction prevention device of the first embodiment. 5 is a perspective view of a main part of a collapsible camera to which the camera malfunction prevention device of the present invention is applied, and FIG. 6 is a side view showing the interior of the lens barrel of the camera shown in FIG. FIG. 7 is a side view of a camera malfunction prevention device showing a second embodiment of the present invention; FIGS. 8(A) (B) ) is a perspective view showing the photographing position and collapsing position of the sector lever in the malfunction prevention device of the second embodiment.

Claims (1)

[Claims] (1) In a camera in which a photographing lens barrel with a built-in shutter blade is moved between a photographing position and a non-photographing position, a driving means for opening and closing the shutter blade and a drive means for moving the photographing lens barrel are provided. and a locking means configured to be displaced in accordance with the photographic lens barrel and occupy a position for preventing the operation of the driving means when the photographing lens barrel is in a non-photographing position. Device.