JPS5837054Y2 - Suritsutoshitao Sonata Camera - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a slit shutter whose slit width is electrically controlled.

A shutter whose exposure is electrically controlled has the advantage of properly controlling exposure, and is particularly characterized by the ability to control high shutter speeds with high precision.

However, in a slit shutter, the shutter speed is determined by the width of the slit I, so the higher the speed is electrically controlled, the narrower the slit 1 width becomes. If the subject is extremely bright, the slit width may become narrow enough to damage the image due to diffraction phenomena, or the shutter may operate without substantially forming the slit width.

Furthermore, if the power battery runs out and the electromagnet stops working, the no-slit shutter will operate regardless of the brightness of the subject.

Such a failure is a serious drawback because the photographer cannot tell whether the photograph was a success or a failure unless the photograph is developed.

In response to this, it has been considered to provide a high-intensity warning display, but if the photographer overlooks this display, the same failure will occur.

As a countermeasure for this, some methods are designed to prevent no-slit by constantly applying a constant load to the shutter closing member, but adding such a load means that the above load will be applied even when shooting at normal brightness. Therefore, accuracy will be adversely affected on shutter performance.

This invention mechanically controls the maximum shutter speed, so
A camera having an opening member and its locking member, and a closing member and its locking member, and in which the locking by the locking member is released by the operation of an electromagnet based on the output of an exposure time control circuit. A pressing member that closes independently and elastically presses the locking member against the electromagnet to prevent the locking member from being unlocked; a release drive member that travels from the charging position by the shirt release operation;
a first acting part that is integrally formed with the release drive member and acts on the opening locking member to release the lock; and a first acting part that acts on the pressing member or the closing locking member and locks the release locking member as the release drive member runs. and a second acting part for releasing the release, and the distance from the charged position of the release driving member until the first acting part acts on the opening locking member is determined from the charging position of the second acting part to the pressing member or the closing locking member. A slit shutter in which the pressing member or the closing locking member is unlocked after a certain short time delay from the unlocking of the opening locking member by providing a difference in the distance between the locking member and the operating position. This camera mechanically limits the minimum width of each sleeve to prevent the above-mentioned drawbacks, makes it possible to photograph extremely bright subjects due to the latitude of the film, and prevents the power supply battery from running out. However, even if proper exposure cannot be obtained, it is still possible to take advantageous photographs.

To explain in detail one embodiment of the present invention with regard to the drawings, the second
In the exposure control circuit diagram shown in the figure, the power switch S1 is first closed in connection with the release operation, and the front part has an aperture device for film sensitivity information, and a shutter speed light receiving element that receives light from the subject. The potential at point A is determined by comparing the resistance values of CdS and resistor R1, but if this is higher than a predetermined potential, the control circuit will cause the light emitting diode L to
Current flows through the ED circuit, which lights up to warn the photographer that hand-held photography is likely to cause camera shake due to low brightness.

Next, in FIG. 1, a release member 2 pivotally mounted to the camera body by a shaft 1 is rotated counterclockwise against a spring 3. As shown in FIG.

In the shutter charging state, a release drive member 4 has a notch 4a that engages with the bent portion 2a of the release member 2 in the clockwise rotation position by the spring 3, and is slidable with respect to the camera body using a pin and a groove. is being moved in the opposite direction of arrow B against spring 5.

The release drive member 4 includes branch arms 4b, 4C, and 4d.
and a bent branch arm 4e.

The switch S2, which engages with the branch arm 4b and short-circuits the resistor R1 in FIG. 2, is opened when the release drive member 4 is charged in the opposite direction of arrow B, and is closed when it moves in the direction of arrow B. .

Further, when the drive member 4 is charged via the branch arm 4C and the overcharge absorbing spring 15, the aperture braking member 7, which is rotated clockwise and charged, has an arc-shaped branch arm 7a and a protrusion 7b. It has a recessed fitting part 7C and a raised part 7d.

The crest drive member 9 is rotatably supported on the camera body by a shaft 8 and has a counterclockwise rotational tendency by a spring 10, and has pins 9a, 9b, and 9C implanted at both ends thereof. The pin 9a is engaged with the protrusion 7d of the embossed brake member 7, and when the embossed brake member 7 rotates counterclockwise from the charging position, the diaphragm drive member 9 also springs. 10 rotates in the direction.

Bifurcated parts 13a and 14 that grip the pins 9b and 9C
The two diaphragm plates 13 and 14 having the shape a are mutually slidable in the direction of arrow B and in the opposite direction, and a diaphragm aperture 13bj4b is bored in the center of each plate, and as the two aperture plates move in opposite directions, The aperture changes depending on the overlap.

In order to control the amount of counterclockwise rotation of the aperture braking member 7 from the charging position, a protrusion 1 that can be engaged with the arcuate branch arm 7a is provided.
1a is rotatably supported on the camera body by a shaft 16, has a spring 12 at one end of its arm for biasing the aperture control member 11 in a clockwise direction, and has a spring 12 on the other arm that biases the aperture control member 11 clockwise. A suction piece 6 is fixedly installed to be attracted by an aperture electromagnet AMg in a counterclockwise rotating position against a spring 12, and a bent piece 11b at the end of the other arm operates to open and close a switch S3.

As shown in FIG. 2, this switch S3 opens and closes a time constant circuit for controlling the shutter speed, which is composed of a light receiving element CdS□, a resistor R3, and a capacitor C2.

Note that the protrusion 7b is for bringing the attraction piece 6 into contact with the electromagnet AMg when the aperture braking member 7 is in the charging position.

As shown in FIG. 2, A' is determined by comparing the resistance values of the resistor R2 and the aperture light-receiving element Cd52, which has an aperture device for film sensitivity information on the front side in addition to the light-receiving element Cd51.
An aperture electromagnet AMg is excited by the output of the control circuit when the potential of the point is lower than a certain value, that is, when the subject brightness is high, and is cut off when the subject brightness is low.
Accordingly, it is determined that the diaphragm control member 11 is either in the suction/holding position or in a position away from this.

At the suction position where the subject brightness is high, the protrusion 11a of the aperture control member 11 is connected to the arcuate branch arm 7 of the aperture braking member 7.
The diaphragm braking member 7 and the diaphragm driving member 9 are locked with a slight rotation within the rotation locus of a, and the diaphragm aperture becomes a small aperture, for example, F:11, but when the subject is of low brightness. At the separated position, the aperture control member 11 is rotated clockwise by the spring 12, and the protrusion 11a is retracted out of the rotation locus of the arcuate branch arm 7a, so the aperture braking member 7 and the aperture drive member are further rotated Rotate clockwise to fully open the opening, for example F.
: Set to 3.5.

The switch S3 is a switch for inputting aperture information into the shutter control circuit, and in a charged state is pressed and closed by the bent piece 11b, and the aperture control member 11 is attracted to the electromagnet AMg. When the diaphragm aperture is controlled to F:11 in the holding position, two parallel resistors are connected to the resistor R3, which is still pressed by the bent piece 11b and is connected in series with the light receiving element Cd51 in FIG. A time constant circuit is formed in which capacitors C and C2 are connected, but when the aperture is opened to F: 3.5,
The pressure by the bent piece 11b is released, and the capacitor C
2 to form a time constant circuit including the light receiving element Cd51, the resistor R3, and the capacitor C1.

The above-mentioned time constant circuit is a time constant circuit that controls the shutter speed, but it also transmits aperture information.

As the release drive member moves in the direction of arrow B after the aperture is determined as described above, the branch arm 4d, that is, the first
The action portion engages with the arm 18a of the opening locking member 18 which is supported on the camera body by the shaft 17, and holds the arm 18a of the opening locking member 18.
9 and rotate it counterclockwise.

The pin 18b implanted in the other arm of the opening locking member 18 is both rotated counterclockwise.

The members 20 and 25 are an opening member and a closing member of the shutter which can be slid in a direction parallel to the arrow B with respect to the camera body using pins and grooves, respectively, and each has an opening in which a slit opening is to be formed in the center. 20b.

25 b, and arrow B by means of springs 21 and 26, respectively.
The cutout portions 20 are biased in parallel with each other and are formed respectively.
a, 25a is the notch 20a in the shutter charge position, the notch 20a is the pin 18b, and the notch 25a is the same as the pin 18b.
a is engaged with and locked with a pin 22a, which will be described later.

Therefore, when the pin 18b rotates counterclockwise as described above, the engagement between the pin 18b and the notch 20a is broken, and the opening member 20 starts sliding in the direction B by the spring 21, as shown in FIG. The trigger switch S4 shown in is opened from the closed state.

The pin 22a, which is implanted in one arm of the closing locking member 22 which is rotatably supported by the shaft 26b and given a counterclockwise rotational tendency by the spring 24, is fixed when the closing member 25 is in the charging position. It engages with the notch 25a to lock the closing member 25, and the other arm of the closing locking member is fixed with an attraction piece 23 that is attracted by the shutter speed control electromagnet TMg.

As mentioned above, when the trigger switch S4 is opened in FIG.
1, and when the level at the point A reaches a predetermined level, the electromagnet TMg is demagnetized by the output of the control circuit.

When the electromagnet TMg is demagnetized, the locking member 22 closes and locks the spring 2.
The closing member 25, which is rotated counterclockwise by the pin 22a and the notch 25a is no longer locked by the pin 22a, is also rotated by the spring 26.
The sliding movement is started in parallel to the arrow B, and the slit width is set by the overlap between the apertures 20b and 25b, and exposure is performed.

Now, with only the above configuration, if the subject brightness is extremely bright, even if the aperture aperture is controlled to F:11, the shutter speed must still be extremely fast, and the actual slit width (diffraction development When the slit width is controlled to be less than (negligible slit width), or due to exhaustion of the power supply battery, the electromagnet TMg becomes unable to attract the attraction piece 23 against the spring 26, and the closing member 25 slides together with the opening member 20. There are cases where the slit width is not formed at all after the movement starts, and in these cases, proper imaging cannot be performed.

Therefore, in the present invention, a suction piece pressing member 28 is particularly provided.

This suction piece pressing member 28 is rotatably attached to the camera body through a shaft 27, is given a clockwise rotational tendency by a spring 29, and is abutted and engaged with the closing locking member 22.

The torque by which the spring 29 urges the closing locking member 22 clockwise is sufficiently larger than the torque by the spring 24 which urges the closing locking member 22 counterclockwise.

Therefore, even if the attraction by the electromagnet TMg is lost, the attraction piece pressing member 28 closes and locks the locking member 22.
As long as the closing member 25 is locked, the closing member 25 is locked in the charging position, and the start of sliding in the direction of arrow B is prevented.

The bending arm 4e of the release drive member 4 is a second action part, and in the stroke of the drive member 4 moving in the direction of arrow B from its charging position, it collides with the suction piece pressing member 28, causing it to spring. 29 in a counterclockwise direction.

In this aspect, as shown in FIG. 3, when the release drive member 4 starts moving in the direction of arrow B from its charging position, each of the branch arms 4 d and 4 e, that is, the first and second acting portions also move in the direction of arrow B. When the release drive member 4 moves by the length α in the direction of arrow B in the case where the electromagnet TMg is not excited, the branch arm 4d moves to the position where it opens and acts on the locking member 18, Since the opening locking member 18 is pressed, the locking of the opening member 20 is released, and the opening member 20 starts sliding parallel to the arrow B by the spring 21, and at the same time opens the trigger switch S4, and the time constant circuit starts counting. Start.

On the other hand, the release driving member 4 moves in the direction of the α+△l arrow B, and the bent branch arm 4e engages with and drives the suction piece pressing member 28, and the bent branch arm 4e acts on the suction piece pressing member 28. If the closing member 25 is to be unlocked when the closing locking member 22 rotates counterclockwise by an angle θ upon reaching the position, the release drive member 4 will slide by α+△α in the direction of arrow B. When it is not, it means that even if the electromagnet TMg is demagnetized, the closing locking member 22 is pressed by the attraction piece pressing member 28 and the locking of the closing member 25 is not released.

Now, the time it takes for the release drive member to move through that △α is 171
000 seconds indicates that exposure at a speed faster than 1/1000 seconds is not performed.

The exposure controlled as described above results in a program diagram as shown in FIG. 4, for example.

In other words, when the brightness of the subject is low from E4 to EV13, the aperture aperture F: 3.5 is 1/100 from 1/2 second.
Exposure for 0 seconds is performed, and when it becomes bright from E■14 to EV17, the aperture aperture is F:11 and the exposure is about 1/90 second to 1/1.
000 seconds of exposure was performed, and the brightness was higher than that of EV18.
Even if it is above, the aperture F: 11 is about 1/1000 seconds.
This indicates that overexposure is being performed.

Furthermore, due to consumption of the power supply battery and disconnection of the circuit, the electromagnet AM
When neither g nor TMg are able to attract the respective attraction pieces 6 and 23, exposure for 1/1000 second is performed at an aperture of F3.5, regardless of the brightness of the subject.

In such an exposure, the EV value during the daytime under normal clear weather is 13 or 14, so when considering the latitude of the film, this indicates that normal photography is possible.

The present invention determines the timing of unlocking of the opening member and the closing member based on the difference in the interlocking positions of one traveling release drive member, the opening locking member, and the closing locking member or pressing member. Even when the subject has extremely high brightness or the electromagnet does not operate due to power supply voltage consumption or disconnection, it is possible to always mechanically maintain a slit width that allows substantial exposure, preventing diffraction phenomena,
This can provide a practical effect of preventing photographing failures due to the no-slit width.

Furthermore, the fastest exposure time can be obtained accurately and reliably.

The pressing member that prevents the closing locking member from releasing the lock always works in the direction in which the closing locking member attracts the electromagnet, so regardless of high brightness or the electromagnet is not activated, the closing locking can be performed for the maximum exposure time. The member can be stopped at the position where it is attracted to the electromagnet.

Further, since this pressing member acts as described above, there is no need to separately provide a mechanism for returning the closing locking member to the electromagnet attracting position when charging the shutter.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing the configuration of essential parts of an embodiment of the present invention, FIG. 2 is a circuit diagram of the same embodiment, and FIG. 3 is a release drive member and an opening locking member in the above embodiment. FIG. 4 is a front view showing the arrangement relationship of the closing locking member and the shutter speed control electromagnet, and FIG. 4 is a chart showing a controlled exposure program. 2... Release member, 4... Release drive member, 4d... First action part (branch arm), 4e
...Second action part (flexed branch arm), 7...
Aperture braking member, 9... Aperture drive member, 11...
... Aperture control member, 13.14 ... Aperture plate, 18 ... Opening locking member, 20 ... Opening member, 22 ... Closing Locking member, 23...
...Adsorption piece, 24...Release biasing member, 25...
... Closing member, 28 ... Adsorption piece pressing member,
AMg...Aperture electromagnet, TMg...
Shutter speed electromagnet, D... Control circuit.

Claims (1)

[Claims for Utility Model Registration] An opening member and a closing member constituting a slit shutter, an opening locking member that locks the opening member in its charging position, and an electromagnet to be excited and controlled by shirt release operation. An exposure time control circuit demagnetizes the electromagnet after a time corresponding to the shutter speed has elapsed, and the electromagnet is attracted and held at a locking position that locks the closing member in the charge position by the excited electromagnet, and the electromagnet is separated from the electromagnet by an exposure time control circuit. A camera comprising a closing locking member that moves from the locking position to the locking release position and unlocking the closing member, wherein a release biasing member that urges the closing locking member to the locking release position. and a member that elastically presses the closing locking member against the electromagnet with a biasing force greater than the biasing force of the release biasing member, regardless of the operation of the electromagnet, so that the closing member is engaged by the closing locking member. a pressing member that prevents release of the lock; a release drive member that is unlatched by the shirt release operation and travels from the charging position due to the force of the biasing spring; and the opening locking member that is integrally formed with the release drive member. a first for releasing the locking of the opening member by acting on the opening member;
and a second function, which is integrally formed with the release drive member and acts to cause the pressing member to release the closing locking member from the locking position as the release drive member travels. and the pressing member, the electromagnet, the release biasing member, and the second acting part, when the electromagnet is in the attracted state at the time when the second acting part acts on the pressing member, and after the point in time. The pressing member is pressed by force and the attracting force of the electromagnet to hold the closing locking member in a position where it is attracted to the electromagnet, and when the electromagnet is in a non-adsorbed state at the time point, the second acting portion and the The release biasing member is configured such that the pressing of the pressing member causes the closing locking member to move away from the electromagnet against a force, and when the electromagnet is in a non-adsorbed state, the opening member and the closing member operate at a maximum speed. When the release drive member is in the charging position and the opening locking member and the closing locking member lock the opening member and the closing member, respectively, so that a slit opening for obtaining the exposure time is formed;
A slit shutter characterized in that there is a difference in the distance from the charging position of the first acting part to the acting position on the opening locking member and the distance from the charging position of the second acting part to the acting position on the pressing member. equipped camera.