JPH058594Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] This invention relates to a barrier opening/closing device that opens and closes a barrier that also serves as protection using a photographic lens constituted by a filter member.

[Prior art]

In recent years, automatic exposure cameras that automatically determine the amount of exposure have become popular, and by using such cameras, even people without advanced photography skills can easily take photographs with optimal exposure conditions. . In addition, high-sensitivity film has become readily available, and by loading this film into an automatic exposure type camera, it is possible to take pictures under optimal exposure conditions even indoors.

However, when high-sensitivity film is loaded into a camera with an automatic exposure function, there is a drawback that when the amount of light is too high, such as when taking pictures outdoors on a clear summer day, the exposure conditions go outside the range of the automatic exposure control, making it impossible to take pictures under optimal exposure conditions. In order to eliminate this drawback, an ND (Neutral Density) is used, which reduces the amount of incoming light when the amount of light goes outside the range of the automatic exposure control.
It would be best if a (neutral density) filter could be automatically inserted into the optical path, but heretofore there has been no practical mechanism for this purpose.

[Purpose and structure of the invention]

Therefore, an object of this invention is to provide a barrier opening/closing device that allows a filter to be inserted and retracted by practical means.

In order to achieve this purpose, this idea
A barrier that protects the lens of the camera is constructed of a filter member, and the barrier is retracted when within the automatic exposure control range, and prohibited from retracting when outside the automatic exposure control range. Hereinafter, this invention will be explained in detail using drawings showing examples.

〔Example〕

FIG. 1 is a block diagram showing an embodiment of this invention, with FIG. 1a being a front view and FIG. 1b being a partial sectional view.

1 is a first running member, 2 is a second running member,
Both are plate-shaped, and the running member 1 has elongated holes 1a, 1
b. The running member 2, which is composed of a rack part 1c, a locking part 1d, a bent part 1e, and a protruding part 1f, and which is disposed parallel to the running member 1, has a long hole part with the same size as the long holes 1a and 1b. 2a, 2b, a locking portion 2d, and a bent portion 2e. Long hole portions 1a, 1b, 2a, 2
b is guided by pins 12 and 13 installed in the inner machine and is attached so as to be movable left and right.
4b to the left in FIG. 1a. When the running members 1 and 2 are both in the position indicated by the solid line in the figure (this state is a set state described later), the right end of the bent portion 1e and the left end of the bent portion 2e are engaged, and the elongated hole portion 1a is engaged. and 2a overlap at the same position, and the elongated holes 1b and 2b also overlap at the same position. Further, at this time, the locking portion 2d is positioned slightly to the right of the locking portion 1d, and the gap between the locking portions is determined in accordance with the operation timing of the hook, which will be described later. The running members 1 and 2 are the first
Collar 1 inserted into pin 12 as shown in figure b
They are arranged in parallel across 2a, and the bent part 1
e and 2e are engaged at a portion indicated by width d. Although not shown, a collar is also used on the pin 13 to ensure space for the traveling members 1 and 2.

The rack portion 1c meshes with the pinion gear of the governor 1g. The governor 1g is used to reduce the moving speed of the traveling member 1 and control it to travel at a constant speed.

The engaging portion 1d engages with the hook claw 3a of the hook 3. The hook 3 is pivotally supported by a shaft 3b and has a suction portion 3c. A relay 4 is provided opposite the suction portion 3c. Relay 4 is a relay that is energized by a release signal. The hook 3 is biased counterclockwise by a spring (not shown), and is designed to rotate counterclockwise as soon as the relay 4 is demagnetized.

The bent portion 2e is a portion that restricts the spring 7 and applies a biasing force when the traveling member 1 is locked with the hook 3. At this time, the spring 7 biases the filter barrier 5 to rotate counterclockwise. The filter barrier 5 is used to protect the photographic lens 15 from dust and the like and to attenuate external light. The filter barrier 5 is shown in FIG.
As shown in , it is pivoted on a shaft 5a, and rotates between a position indicated by a solid line, where a is inserted closer to the optical path than the lens 15, and a position indicated by a chain line, where it is retracted from the optical path. The filter barrier 5 is urged clockwise by a spring 6 which is weaker than the spring 7. The spring 6 is a spring for retracting the filter barrier 5 from the optical path. The pin 16 is a member for regulating the right rotation end of the filter barrier 5.

The protrusion 1f engages with a pin 8c set on the set lever 8. The set lever 8 is a lever for setting the traveling member 1. The set lever 8 is biased counterclockwise by a spring (not shown),
It rotates around the axis 8d. A pin consisting of a large diameter portion 8a and a small diameter portion 8b is implanted in the center of the set lever 8. The large diameter portion 8a engages with the cam 9. The cam 9 is provided coaxially with the gear 10a. The rotation of the motor 18 is connected to the gear train 1 in the gear 10a.
0. The motor 18 is a motor for driving a camera motor.

A rewind button 11 is a button for instructing rewinding of the film. By moving the rewind button 11 in the direction of the triangle mark, the motor 18 is rotated in the reverse direction and the film is rewound by a rewind mechanism (not shown). The rewind button 11 engages with the small diameter portion 8b of the set lever 8 through a protruding portion 11a, and sets the traveling member 1 to the set position no matter where it is stopped when it moves rightward. The reason for operating in this way is that motor 1
This is to separate the large diameter portion 8a from the cam 9 so that the cam 9 can rotate in the reverse direction when the cam 6 reverses to rewind the film.

First, the operation when the ambient brightness is within the automatic exposure range will be explained. Normally, the filter barrier 5 covers the lens 15 in the state shown in FIG. 1a. At this time, even if the filter barrier 5 is opened and closed from the outside, no load is applied to the internal mechanism because it is only biased by the springs 6 and 7.

When a release button (not shown) is pressed, the relay 4 is energized, attracts the suction portion 3c of the hook 3, and rotates the hook 3 clockwise. Therefore, the engagement between the hook pawl 3a of the hook 3 and the engaging portion 1d of the running member 1 is released, and the running members 1 and 2 are moved by the springs 14a and 14b.
Both start running to the left due to the urging force of .

As the traveling member 2 travels, the bent portion 2e is pressed against the spring 7.
Since the filter barrier 5 is no longer restricted, the filter barrier 5 is rotated clockwise by the biasing force of the spring 6 and reaches the retracted position shown by the chain line. At the same time, the traveling member 1 moves to the left end, releases a hook (not shown), and opens the shutter. At this time, since the filter barrier 5 is removed from the optical path, the camera is performing normal automatic exposure operation.

Next, we will explain the operation when the ambient brightness is too bright and the camera is out of the automatic exposure control range, resulting in overexposure even at the minimum aperture and maximum shutter speed. At this time, based on the information that it is outside the automatic exposure control range, the supply period of the current supplied from the control circuit described later to the relay 4 is shorter than when the surrounding brightness is within the automatic exposure control range. It is set to be. Therefore, the relay 4 is energized for a short time, and when the energization is released, the hook 3 rotates counterclockwise. At this time, if the time required to energize the relay 4 is set as the time required for the hook claw 3a and the engaging portion 1d to disengage, the running member 1 will be disengaged and run to the left, but the running member 2, the portion of the hook 3 that rotates to the left when the bias is released, the hook pawl 3a and the engaging portion 2d engage with each other, so that the hook 3 stops at the position shown by the two-dot chain line. In this state, spring 6
Since the force of the spring 7 is stronger than the force of the filter barrier 5, the shutter is opened while the filter barrier 5 remains covering the lens 15.

Since the filter barrier 5 is inserted into the optical path, the light that enters the optical path is attenuated by the filter barrier 5, and even if the surroundings are too bright or outside the automatic exposure control range, it will reach the lens 5. The light can be within automatic exposure control range. Therefore, it is now possible to take pictures under the optimum exposure conditions even in places that are too bright, where it was previously impossible to take pictures under the optimum exposure conditions.

After photographing, the motor 18 rotates in the forward direction through gear train 1.
0, rotate the cam 9 clockwise. As the cam 9 rotates, the set lever 8 is rotated clockwise by the large diameter portion 8a serving as a follower. Since the pin 8c at the tip of the set lever 8 engages with the protrusion 1f and moves the traveling member 1 to the right, the bent portion 1e pushes the bent portion 2e while the traveling member 2 also moves to the right and bends. The starting portion 2e restricts the spring 7, and the filter barrier 5 rotates counterclockwise. At this point, the photographing lens 15 is again connected to the filter barrier 5.
covered with When the running member 1 further reaches the right end,
Since the relay 4 is no longer energized, the hook pawl 3a engages with the locking portion 1d of the traveling member 1 and returns to the initial state. The current supplied to the relay 4 is generated by a control circuit 33 as shown in FIG. This control circuit 33 determines whether or not the exposure condition is within the automatic exposure control range based on the signals supplied from the photometry circuit 31 and the film sensitivity detection circuit 32, and if it is within the automatic exposure control range, a release signal is sent. When the release signal is supplied from the generating circuit 30, a signal having a long time width for disengaging the hook pawl 3a from the engaging portions 1d and 2d is supplied to the relay 4, and if it is outside the automatic exposure control range, the hook pawl 3a is released. A signal having a short time width for disengaging only the engagement portion 1d is supplied to the relay 4.

In the above embodiment, the shutter is opened in the final region of the running member 1, but the shutter is opened by driving a separately provided shutter opening circuit using a release signal generated from the release signal generating circuit 30. Also good. Alternatively, two hooks 3 may be provided, each of which engages with the engaging portions 1d and 2d, and depending on the exposure conditions, it may be selected whether to disengage the engaging portions 1d or to release both hooks. In this case, the curved part 1e
Alternatively, the running member 2 may be provided with a protrusion similar to the protrusion 1f, and this protrusion may be engaged with the pin 8c to return the running members 1 and 2 to the set position. In addition, the filter barrier 5
Use a color temperature correction filter instead of an ND filter,
Evacuation may be prohibited only when color temperature correction is performed.

[Effect of idea]

As explained above, in this invention, the first running member performs shutter control, and the second running member performs drive control of the barrier, which also serves as a filter material, so that the surrounding brightness is controlled by automatic exposure control. When within the range, both the first and second running members are run to perform shutter control and barrier retraction control.
In addition, when the ambient brightness is brighter than the automatic exposure control range, the second traveling member is prohibited from moving, thereby prohibiting the filter barrier from retracting, so it is possible to take pictures under optimal exposure conditions over a wide light amount range. It has the effect of being able to perform the following.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the barrier switching device according to the present invention, in which FIG. 1a is a front view, FIG. 1b is a partial sectional view, and FIG. FIG. 3 is a block diagram of the generated portion. 1, 2... Running member, 1a, 2a, 1b, 2b
...Long hole part, 1c...Rack part, 1d, 2d...
Locking part, 1e, 2e... curved part, 1f... protruding part, 3... hook, 3a... hook claw, 3c...
Adsorption part, 4... Relay, 5... Barrier for filter, 6, 7, 14a, 14b... Spring.

Claims (1)

[Scope of Claim for Utility Model Registration] A barrier opening/closing device in which the barrier 5 that protects the photographing lens of a camera is constituted by a filter member and is driven to open and close between a position inserted into a photographing optical path and a retracted position, which is rotatable. a hook 3 having a claw portion 3a at its rotating tip; a first biasing means 6 that applies a biasing force to move the barrier to the retracted position; a second biasing means 7 for moving the barrier to a position in the photographing optical path with a biasing force stronger than that of the barrier; a first running member 1 whose first locking portion locks onto a claw portion of the hook;
and a second bent part 2e which is regulated by the first bent part in the initial set position, and after the hook part and the first locking part are released from each other, the hook part a second running member 2 having a second locking portion 2d that locks the hook; a setting means 8 for returning and setting the running member to the initial setting position after photographing is completed; and a control circuit for selectively controlling the rotation time of the hook driven by the control circuit, when the surrounding brightness is within the automatic exposure range, the rotation time of the hook and the first locking portion are controlled. The value is such that the engagement of the hook is released and the hook does not engage with the second engagement part, and when the surrounding brightness exceeds the automatic exposure range, the hook does not engage with the first engagement part. 1. A barrier opening/closing device characterized in that the value is set such that the value is such that the second engaging portion is engaged with the second engaging portion.