JPH07168260A - Camera - Google Patents

Abstract

PURPOSE:To provide a camera in which a battery is saved and with which a photograph having no failure is taken. CONSTITUTION:This camera is provided with (a) a charging means for charging a capacitor for stroboscope, (b) a timer means measuring specified time with the start of charging by the charging means, (c) a charging state detecting means detecting the charging state of the capacitor, (d) a film exposing means for exposing film, (e) when the charging state detecting means detects that charging is not completed in the specified time measured by the timer means, the charging of the capacitor by the charging means is stopped and exposing the film by actuating the exposing means is prevented from being performed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improved strobe device for a camera, particularly for an automatic type camera having a built-in strobe.

[0002]

2. Description of the Related Art In a fully automatic camera, that is, a camera incorporating an automatic exposure control device and a strobe, and in some cases, an automatic focusing device, it is possible to obtain various combinations of subject brightness and subject distance. Each had to decide whether or not to fire a strobe.

By the way, the strobe device for emitting light from the strobe requires a charging voltage for the capacitor to obtain sufficient light emission. Therefore, the conventional strobe device detects the charging voltage of the capacitor to be charged. , It was controlled so that shooting could be performed when charging was completed.

However, in this case, when the battery is weak or the temperature of the outside air is extremely low, the charge control of the condenser for obtaining the strobe light amount adapted to the photographing condition is continuously performed, so that the battery is consumed. Will be done.

Then, the charging of the capacitor is completed,
It may be possible to take a photo after a preset time has passed, regardless of whether or not the photo is taken, but in this case, an underexposed photo will be taken, resulting in a failed photo and battery drain. Not to mention waste of film.

[0006]

Generally, photography is performed under various scenes and conditions, and it is necessary to subdivide these various conditions and determine the optimum photography and parameters for each case. Has the drawback of complicating the system for automating the camera. Also, of course,
The diversification of these shooting conditions also causes the camera to have a plurality of function controls, which leads to the drawback of shortening the life of the battery that supplies current to these functions. For example, in the case of a strobe device, it takes a long time to charge the capacitor, and it takes time to shoot,
It may also cause you to miss a photo opportunity.

Therefore, after a predetermined time, for example, it may be considered that the charge is cut off to take a picture even during charging, but as a result, the picture taking state is not reflected and a predetermined luminance is not sufficiently obtained. For the time being, because it will only compensate for the timing when shooting, it will save the battery, but it will take a picture different from the photographer's intention and it will not be a fundamental solution to the problem. .

The present invention was conceived in particular in order to eliminate the above-mentioned drawbacks. That is, it is an object of the present invention to provide a camera that saves the battery and takes a picture without failure, and an object of the present invention is to provide a camera that solves the problem. It is a thing.

[0009]

To achieve the above object, according to the present invention, in claim 1, (a) charging means for charging a strobe capacitor, and (b) with the start of charging of the charging means, Timer means for measuring a predetermined time, (c) charge state detection means for detecting the charge state of the capacitor, (d)
A film exposing means for exposing the film,
(e) When the charging state detecting means detects that the charging is not completed within the predetermined time measured by the timer means, the charging of the capacitor by the charging means is stopped and the exposure means operates. Configured so that film exposure is not performed.

A first release switch which is operated by a first pressing of a release button, and a second release switch which is operated by a second pressing which further presses the release button from the first pressing. The charging start of the charging means is achieved by being performed based on the operation of the first release switch.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a front view of a specific example of the present invention. 1 is a camera body, 2 is a slide cover which can slide in the direction of arrow A, 3 is a stroboscopic light emitting unit provided on this slide cover, and 4 is a photographing device. A lens, 5 is a release button, 6 is a viewfinder, 7 is a metering window of an automatic exposure control device, 8 is a light projecting window of an automatic focusing device, and 9 is a light receiving window of an automatic focusing device. When the slide cover 2 is slid in the direction of arrow A to match the main body 1, the lens 4, the finder 6, the various windows 7,
All 8 and 9 will be hidden by the slide cover.
The camera in the figure is a camera that uses a disc film, and 10 is a lever that opens and closes a light shielding plate of the disc film cartridge. Also, this lever is a back cover opening / closing lever, and the back cover lock can be released by raising this lever.

Then, when the disc film cartridge is loaded, the back cover is closed, and the lever 10 is tilted down to the state shown in the drawing, the back cover is locked and the cartridge light-shielding plate is opened.

FIG. 2 is a block diagram of one embodiment of the present invention, and FIG. 3 is a detailed circuit diagram thereof.

In the figure, A is a logic control circuit which comprises a CMOS one-chip microcomputer (hereinafter referred to as a microcomputer). Reference numeral B denotes a distance measuring circuit, which includes a light emitting diode LED1 for light projection and a distance measuring sensor SD. Although not shown in the figure, the sensor SD is composed of two phototransistors and a processing circuit, and the subject distance is measured by comparing the magnitudes of the outputs of the two phototransistors.

Reference numeral C is an automatic exposure control photometric circuit, which comprises a photoconductive element CdS and a comparator C _1. The comparator C ₁ determines whether the subject is bright or dark. Reference numeral D denotes a power supply voltage detection circuit, which is composed of a constant voltage element D ₁ and a comparator C _2, and prohibits charging of the strobe when the power supply voltage VDD of the microcomputer becomes lower than a predetermined value (for example, 3.2 V) during strobe charging. . This prohibition control is automatically performed in the strobe circuit as described below.

E is a power supply control circuit, which is a switching element T.
It consists of R ₁ and TR ₂ . For example, the first release switch S ₁
When is turned on, TR ₂ becomes conductive and supplies power to the microcomputer, photometric circuit, etc. Similarly, TR
_{When 2} becomes conductive, the strobe charge is prohibited and the motor brake circuit operates. In addition, power supply VDD and VCC
Resets the microcomputer through the reset circuit K, and after this reset, first, a power hold signal is output from the terminal PH of the microcomputer,
The power supply voltage VDD is self-held until a predetermined operation ends.

F is a strobe circuit. The strobe circuit is well known, so its explanation is omitted. However, since this circuit is related to the power supply voltage detection circuit D, this point will be described. A switching element TR ₃ for controlling ON / OFF of a booster circuit composed of an oscillation transistor TR ₄ and coils L ₁ and L ₂ is controlled by an STS of a microcomputer and a comparator C ₂ . That is, even if the strobe is being charged, the comparator C ₂ becomes LOW level by the STS signal signal when the voltage VDD becomes lower than the predetermined voltage, the switching element TR ₃ becomes conductive, and the oscillation transistor TR ₄ becomes non-conductive. And prohibit charging.

The minimum operating voltage of the microcomputer used in this embodiment is about 3V, and operation at a voltage below that is not guaranteed. However, it has been found that the power supply voltage VDD may be 3 V or less due to the starting current at the initial stage of strobe charging. Therefore, when the power supply voltage VDD is about to become 3 V or less, it is necessary to suspend the charging and prevent the power supply voltage from decreasing.

Even when the charge is temporarily stopped by the operation of the comparator C ₂ , the charge command of the microcomputer, that is, the STP signal continues, the power supply voltage is restored, and the comparator C ₂ becomes HIGH. The strobe circuit can be charged. Actually, by repeating such an operation, the strobe is gradually charged, the charging flow is reduced, and charging can be performed under the condition that the current voltage VDD does not become 3 V or less, and the target charging voltage is reached.

The strobe charging mode described above is shown in FIG. 4 in comparison with the conventional example (operation mode in the concrete example of FIG. 4A and FIG. 3 and operation mode in the conventional example of FIG. 4B).

In the conventional power supply voltage detection circuit, the open circuit voltage of the battery or the battery voltage under the condition that a load current of about several mA is applied is measured before actually operating the strobe etc., and a warning is displayed according to the result. The common method is to lock or release lock. However, according to this, in order to guarantee the operation in consideration of the internal resistance of the battery, the load condition, etc., it is necessary to perform the release lock or the like in a state where the battery has a reserve capacity. In the illustrated embodiment, the power supply voltage when the strobe is actually operating is detected in a state including the internal resistance of the battery, load conditions, etc., so that the capacity of the battery can be used to the limit.

Further, when the motor is operated, the temporary interruption can be performed in the same manner as above.

G is a motor circuit, which is composed of four transistors TR ₅ , TR ₆ , TR ₇ , and TR ₈ , and when the signal is output from the terminal CW of the microcomputer, the transistors TR ₆ and TR ₈ become conductive, When the motor M is normally rotated and a signal is output from the terminal CCW, the transistors TR ₅ and TR ₇
Turns on and reverses the motor M. Note that the electromagnetic brake is applied to the motor when the motor stops rotating forward.

As shown in FIG. 3, since the CCW is supplied at least while the power hold signal is being output, the transistor TR ₇ is normally on.

When the signal CW is HIGH, the motor M is rotated in the forward direction, so that TR ₇ is turned off at TR ₉ . Signal C
Even after W becomes LOW, the motor continues to rotate by inertia, so that the motor is operated beyond a predetermined amount driven by the motor. To prevent this, it is well known to quickly bring the voltage across the motor to zero.

In the example of FIG. 3, the problem is solved by adding a simple brake function to the bridge circuit for performing the normal and reverse rotation of the motor.

Conventionally, in order to perform the braking operation in the bridge circuit, for example, there is a method of applying a signal in the reverse direction for a predetermined time after the normal rotation, but it was difficult to set this time appropriately. For example, if the reverse rotation time is too long, the motor will stop and then reverse. If the time is too short, the braking effect will be weakened.

In the specific example of FIG. 3, since TR ₇ is turned ON after the motor is rotated in the normal direction, the motor (+) → TR ₇ collector → TR ₇ emitter → D ₂ anode → D ₂ cathode →
An effective electromagnetic braking function is achieved by forming a closed group called a motor (-) and quickly reducing the voltage across the motor to zero.

FIG. 5 shows another example of the motor drive circuit.

TR ₆ ′ and TR ₈ ′ are turned on by the signal CW, the motor M ′ is normally rotated, and TR is turned on by the signal CCW.
₅ ', TR _7' that is the same as the example of FIG. 3 to be reversed motor M 'and conduction. In this example, the brake signal effectively applies braking to both forward rotation stop and reverse rotation stop, and moreover, current is not supplied to the transistor TR ₉ ′ constituting the brake circuit except when the brake is activated, so that power saving is achieved. Great effect. I is an oscillating circuit, which outputs a clock necessary for controlling the microcomputer.

H is a strobe trigger control circuit, which transmits the ON state of the mechanical sync switch SSW to the trigger input of the strobe circuit when either one of SOL1 and SOL2 to be described later is turned on.

Before describing the operation of the camera according to the present invention, the main switches provided in this camera will be described.

<Main Switch MSW> The camera according to the present invention has one power source.
Power is supplied to all of the drive unit and strobe circuit unit, and the main switch MSW is a switch for connecting and disconnecting this power supply to the control unit, drive unit and strobe circuit unit, etc. The electrical system of will be deactivated. This main switch is turned off when the slide cover that protects the lens and viewfinder is closed.
It is turned on when opened.

<Reset switch RSW> This is a switch for resetting the logic control unit, that is, the microcomputer to the initial state, and is turned on when the opening / closing lever (lever 10 in FIG. 1) for opening and closing the back cover is raised, and when it is tilted. O
It is a switch for FF.

<First Release Switch S ₁ > This switch is turned on when the release button is pressed, and is turned on when the release button is pressed lightly.

<Second Release Switch> This switch is turned on when the release button is pressed, and is different from the first release switch S _{1 in that} it is turned on when the release button is pressed deeply.

<Notch Switch NSW> This is an operation switch related to the notch for determining the position of the frame provided on the outer periphery of the disc film, and it is turned off when the switch arm enters the notch, and when it exits the notch. This is a switch that turns on.

<Reverse Switch GSW> A camera using a disc film normally carries out film feeding, shutter charging, and shutter operation with a single drive source, which is carried out using a mechanism using a planetary gear.

That is, when the torque required for film feeding and the torque used for shutter charging are in a state where film feeding is possible, the driving force of the motor is not transmitted to the shutter charge mechanism, and when the film feeding is locked, the shutter is released. It is designed so that the driving force of the motor is transmitted only to the charging mechanism.

When the claw for positioning the photographing frame at a predetermined position enters the notch provided on the outer periphery of the disc film and the film cannot be fed, the shutter charging cam wheel rotates and the claw is disengaged from the notch. In, the cam wheel for shutter charge does not rotate, and film feed is performed. The reverse rotation switch GSW is a switch operated by another cam provided in the shutter charging cam wheel, and is turned on immediately after the initial position where the claw enters the notch and the cam wheel starts to move to perform shutter release (operation). It is a switch that is turned off before.

Next, the operation of one specific example of the camera according to the present invention will be described for each operation mode.

1 Shooting Preparation Mode A description will be given mainly with reference to FIG. 7 which is a time chart diagram of the shooting preparation mode and FIG. 6 which is a flowchart.

First, by raising the lever 10 for opening and closing the back cover, the reset switch RSW is turned on and at the same time the back cover is opened, and the cartridge can be loaded. Since the reset switch is turned on at this time, the camera does not operate even if the user operates the release switch or the like.
When the cartridge is loaded and the case back is closed, the open / close lever 10 is tilted and the reset switch RSW is turned off, whereby the microcomputer MC becomes operable.

Next, by turning on the main switch MSW, the microcomputer MC and the VB rise detection section of the power supply control circuit E are activated, and the power supply voltage VDD rises. With this signal, the power hold terminal PH of the microcomputer MC is supplied. Power is held by the signal (PH, ON-1).

Almost at the same time, a signal is output from the terminal CW of the microcomputer MC and the motor M is normally rotated. The motor rotation at this time is performed when the notch switch is turned on or off in the microcomputer MC as shown in FIG. 6 (judgment NSW1) and is turned on (motor forward rotation-1). , OFF, that is, until the notch claw enters the notch and the first frame of the film is sent to the predetermined position, and stops when it is sent to the predetermined position (motor stop-4). The operation mode when the notch switch NSW does not operate will be described later.

After the motor has stopped, a predetermined time Δt ₁ hour for recovering the power source power, a strobe charging is performed by a signal from the strobe charging signal terminal STP of the microcomputer MC, and the microcomputer MC terminal EN.
Charging is performed until a charge completion signal is input to D. It should be noted that even if the charging completion signal is not output within the predetermined time period created by the timer T ₃ , the charging is stopped, and after the time period (2.5 seconds) created by the timer T ₇ after the charging is stopped, the power hold circuit is turned off.
After that, the whole system stops. In the normal shooting preparation mode, the release button cannot be pressed only by loading the film, opening the slide cover of the disc film and putting it in the standby state. Therefore, at the judgment S ₂ -4, the second release switch S ₂ is turned off. After being judged, the power hold is turned off after the time (2.5 seconds) created by the timer T ₄ and the whole system is stopped.

2 Normal Shooting Mode As a matter of course, the normal shooting operation is started by pressing the release button. That is, the first release switch S
Start with ₁ ON.

Thereafter, the power supply voltage VDD rises, the power is held, and the notch switch NS is determined by the judgment NSW-1.
It is the same as the operation in the photographing preparation mode described above that it is determined whether W is ON or OFF, strobe charging is performed by EF charging 1, and charging stop 2 is performed. When the release button is pressed, the first release switch S ₁ and then the second release switch S ₂ are turned on. Therefore, the determination S ₂ in FIG.
At S-4, it is determined that S ₂ · ON, and then in determination ST, it is determined whether the self-timer switch ST is ON or OFF. In the case of normal photographing, ST is OFF and the process proceeds to the photometry and ranging step.

This step will be described with reference to FIG. After turning on the second release switch S ₂ until the power supply becomes stable, the metering data after Δt ₂ is read, that is, the ED is read, then the distance measurement timing signal FLD is output, and the LED 1 for distance measurement is generated, Distance signal reading, that is, FD reading is performed. The photometric data ED and the distance measuring data FD are both binary signals indicating whether the subject is dark (EV12 or less) or bright, whether the subject is far (1.2 m or more), or far.

In the camera of this specific example, the aperture is controlled in two steps of F2.8 and F8, and the close-up lens is automatically set in the taking lens system for a short-distance subject. Has been.

More specifically, the close-up lens is configured to move in and out of the optical system by a cam mechanism each time the shutter is charged, and the magnet SOL2 operates at a short distance to hold the close-up lens in the photographing optical system. Since the magnet SOL2 is not operated at a long distance, the close-up lens is retracted outside the photographing optical system.

SOL1 is a diaphragm control magnet, which is set to F2.8 when it is ON, and to F8 when it is OFF. Also, strobe light emission control is automatically performed. SOL2 is a magnet for controlling the close-up lens, and its mechanism is as described above.

The control of the diaphragm, strobe light emission, and close-up lens is processed by the logic shown in FIG. That is, when the subject is at a short distance, SOL1 is OFF and the aperture is set to F8, that is, a small aperture, and S
When OL2 is ON, the close-up lens is held in the photographing optical system and controlled so that a strobe trigger signal is output.

When the subject is at a long distance and is bright, SOL1 is turned off and the aperture is set to F8 (small aperture).
When SOL2 is also OFF, the close-up lens is located outside the photographing optical system at the time of exposure, and the strobe trigger signal is controlled so as not to exist.

SOL1 when the subject is at a long distance and dark
Is ON, the aperture is set to F2.8, that is, the aperture is set to the full aperture, SO
L2 is OFF and the close-up lens is outside the optical system and is controlled so that a strobe trigger signal is output, as described above. A characteristic feature of this processing is that when the subject is at a short distance, the aperture is set to a small aperture (for example, F8) and the strobe light is emitted regardless of the brightness. This is because the subject is not extremely bright in most cases in close-up photography, apart from the background, and close-up photography is often done indoors or in a low state. It is a process based on statistical results that a good picture can be obtained by taking a picture with deeper flash and making the strobe light.

In particular, the above processing is effective in a system such as this camera in which the diaphragm and the lens are controlled in only two stages. It should be noted that this processing method is also effective when controlling the diaphragm and the lens in three or four stages, respectively.

The routine between the distance measurement and the motor forward rotation 3 in FIG. 6 is a step for setting the above-mentioned photographing conditions.

In order to confirm that the close-up lens is operating reliably during short-distance photography, the LED2 is lit and displayed until the SOL2 is turned on and the motor is next activated.

In FIG. 3, the self-timer operation display LED 2 described later is also used as the above display. That is, the driver DR ₁ is activated when either the self-timer LED signal SLD or the SOL2 signal FMG is output.

When the motor M is operating, the display L
Supply voltage of ED2 is changed, sometimes the LED flickers, when the motor forward rotation signal CW is output to actuate the driver DR _2, is off the display LED2.

Next, the forward rotation 3 of the motor is performed. In this case, since the claw is in the notch of the film, the film does not rotate.
Under the conditions of L1 and SOL2, the aperture close-up lens is set and then the shutter operation is performed to expose the film. Further, in synchronization with the shutter being fully opened, the synchro switch SSW is turned on, and in the case of stroboscopic photography, a trigger signal is issued and the strobe emits light.

After the film exposure, the motor continues to rotate forward, the cam wheel is rotated, and the pawl comes off the notch. The operation of the claw is also performed by the above-mentioned shutter charge and another cam provided in the shutter operation cam wheel. When this claw comes out of the notch, the notch switch NSW turns off almost at the same time.
N, the SOL1 and SOL2 are turned off (SOL, O
FF), and cancels the set shooting conditions. When the pawl comes out of the notch, the rotation of the cam wheel stops, the rotational force of the motor is transmitted to the film, the film rotates, the pawl rotates until it enters the next notch, and when the notch enters the next notch, the notch switch The motor stops with the NSW OFF signal. After the motor is stopped, strobe charging (EF charging-2) is performed again, and the strobe power supply capacitor is charged with electric charge for the next shooting. When the charge completion signal END is output, the strobe charge is completed, the power hold is turned off, and the power supply voltage VD
D goes LOW, shutting down the entire system.

In the above operation, the reverse switch GSW is momentarily turned on immediately before the shutter is charged by the cam provided on the cam wheel for shutter operation. This is for the operation after the end of the last frame photographing described later. However, it is ignored in this normal shooting mode. That is, the judgment GSW3 in FIG. 6 enters the routine when the notch switch NSW is ON and the reverse rotation switch GSW is ON in the judgment NSW2, and the operation in another mode is started.
Since there is no time point when NSW and GSW are simultaneously turned on in this operation mode as shown in, the NSW 3 advances to motor stop 7 and the above-mentioned operation is performed.

This camera is designed for single shooting and continuous shooting. Prior to shooting, the shooting car should
The continuous shooting mode can be selected by the changeover switch. Judgment S to see whether it is single shot or continuous shot after EF charging 2
/ C is performed, and in the case of single shooting, the route proceeds to the route indicated by OFF, and power hold OFF (PH, OFF3) is performed. In the case of continuous shooting, proceed to the route indicated by ON and make a decision S ₂
-2 to see if the second release switch S ₂ is ON or OFF. If it is OFF, the power hold is turned OFF, and if it is ON, the process returns to the judgment ST, and a series of photographing operations such as photometry, distance measurement, and shutter operation are performed again. The operation is performed.

3. Self-timer shooting mode In the camera according to the present invention, the shooting operation by the self-timer is performed independently of the release button. That is,
Only by pressing the self-timer button, the self-timer operation and the subsequent shooting operation are performed without pressing the release button. When the self-timer button is pressed, the self-timer switch ST turns on.

When ST is turned on, the power source VDD rises, the power hold PH, turns on, and the strobe charge is stopped. The same operation as described in the normal photographing mode is performed.

The self-timer switch ST, the first release switch S ₁ and the second release switch S ₂ are composed of the circuit shown in FIG.

That is, the self-timer switch ST is turned on.
Then, not only the terminal ST that enters the microcomputer MC, but also the input terminal S ₂ and the switching element TR ₁ are turned on at the same time. Therefore, after the flash charging stop determination S ₂ -
S ₂ is also determined that the ON in 4, the process proceeds to decision ST. Next, L that indicates that self-timer shooting is in progress
The ED display is performed by turning on the LED 2, and it is determined whether 10 seconds have passed. After 10 seconds, the same operation as in normal shooting mode is performed. Traditionally,
As with this camera, the self-timer operates independently of the release button. That is, there is known a camera which operates so that the shutter is automatically released after a predetermined time elapses by pressing the self-timer button. For example, Konica FS-1 (manufactured by Konica Corporation).

However, in the past, the switch structure was complicated because the self-timer release switch was mechanically configured so that the above-mentioned S ₁ , S ₂ and ST were turned on. According to the circuit shown in FIG. 15, a simple and inexpensive switch such as a conductive rubber switch used in a calculator or the like is sufficient.

As shown in FIG. 6, photometry, distance measurement, aperture setting based thereon, and focusing of the optical system are performed after the self-timer operation is completed. Therefore, for example, even when the subject moves and the subject distance changes during the operation of the self-timer, a focused photograph can be obtained.

4. Self-timer Release Mode In the camera according to the present invention, the self-timer can be set and then released during operation. Figure
10 shows a time chart of this self-timer release mode.

After turning on the self-timer ST to start its operation, pressing the self-timer button again to turn on the switch ST causes the judgment ST in FIG.
Upon release, it is determined that there is release, and the power hold PH is turned off after a predetermined time (2.5 seconds) created by the timer T _7.
F, and the whole system stops.

5. Final Shooting Mode From step S ₁ to SOL OFF in FIG. 6, the process proceeds in the same manner as the normal shooting mode.

Although the film is fed after the shutter is actuated by the rotation of the motor, after the last frame is photographed, the film is not delayed after being fed a little in the disc film system. Therefore, the notch claw is in a state of coming out of the notch of the film. Will stop. Therefore, the notch switch NSW continues to be in the ON state as shown in FIG. Therefore, the determination NSW2 is determined to be ON, and in this state, the shutter charge and the cam wheel are continuously rotated. The cam wheel returns to the initial position again and tries to continue rotating, but at this time, the reverse rotation switch GSW is turned on, so it is determined that the determination GSW-3 is ON, and the motor stop 1 and the motor reverse rotation are performed. . Then, the motor reverses and then stops until the reverse rotation switch GSW is turned off again by the reverse rotation of the cam wheel. Power hold is OFF after the motor is stopped
And the whole system is shut down.

If the reverse rotation is not performed after the final frame is photographed, the notch switch NSW remains ON, so the motor continues to rotate, but the film does not rotate any more due to the structure of the cartridge. Will be transmitted. The cam wheel makes one rotation, shutter charge is started again from the initial position, and shutter release is performed. After that, this is repeated until the motor stops, and the film becomes multiple exposure. In order to prevent this, after taking the last frame, before the cam wheel charges the shutter again, the cam wheel is reversely rotated and returned to the initial position, and then the motor is stopped.

Further, FIG. 12 shows an operation for prohibiting photographing in the above-mentioned state.

6. Shooting Prohibition Mode After Shooting the Last Frame It is quite possible that the user accidentally presses the release button even after shooting the last frame. FIG. 12 is a time chart of the operation in such a case. As shown in FIG. 11, the notch switch NSW remains in the ON state after the final frame shooting is completed.

In this state, the first release switch S _{1 is} turned on.
Is performed, it is determined that the notch switch NSW is ON at the determination NSW-2 after power hold. Then the motor rotates forward. The cam wheel is rotated by the forward rotation of the motor, and the reverse rotation switch GSW is turned on. Therefore, the motor reverse rotation is performed as in the last frame shooting mode, the motor stops when the reverse rotation switch GSW is turned off (motor stop-2), the time hold power hold by the timer 7 is turned off, and all switches are stopped. To do.

7. Empty shooting mode Even if there is no film in the camera, the user may accidentally press the release button. FIG. 13 is a time chart showing the operation of the camera in such a case.

First, the first release switch is turned on (S
₁ ON), the operation is started, but from this step, the EF charging, the charging stop, the photometry, the distance measurement, and the motor forward rotation-3 are performed as in the normal photographing mode.

The notch switch NSG is turned off when the nail is in the notch of the film, and is turned off when the nail is off the film notch and is on the film.
What has been done N is as already explained.

When there is no film in the camera, the nails are in a free state, which is the same as when the film enters the notch of the film. Therefore, when there is no film in the camera, the notch switch NSW is in the OFF state.

Therefore, at the judgment NSW-2, NSW, O
It is judged to be FF, the motor stops after the time created by the timer T ₅ , (motor stop-5), and after the time created by the timer T ₇ , the power hold turns off and the entire system stops. The motor sound at this time allows the user to know that the film is not loaded.

In the operation of the camera of the present invention described above, one of the characteristic points is that at the end of each operation, the power hold is continued for a predetermined time (2.5 seconds) after the operation of the element is completed, and this time ends. After that, the power hold is released and the whole system stops (Fig. 7, Fig. 10, Fig.
(See the termination timer C in FIGS. 11, 12 and 13 and the timer T ₇ in FIG. 6).

This prohibits the input of external signals to the microcomputer MC during this period, and when the photographer makes a post-operation,
This is to prevent the camera from performing unnecessary operations continuously without waiting time and the battery consumption associated therewith.

A supplementary explanation will be given on the EF charging surrounded by the alternate long and short dash line in FIG. After EF charging, the elapsed time after made by a timer T _3, noted when not out charge signals from the strobe circuit stops charging (charging stop -1), to stop the entire operation.

Then, after waiting for the battery to recover, again,
By accepting the first release switch S ₁ again and recharging it again, the battery can be used effectively.

[0088]

As described above, according to the present invention, when the charging of the strobe is not completed within the predetermined time, the strobe is prevented from being charged and the film is not exposed. It is possible to prevent the consumption of, and not to take a failure photo.

In some cases, it is possible for the photographer to determine that there is something abnormal due to the inability to perform the above operation, and as a result, there is an additional effect that it can also serve as a warning prompting replacement of the battery. is there.

[Brief description of drawings]

FIG. 1 is a front view showing a specific example of a camera of the present invention.

FIG. 2 is a block diagram of a control / driving unit in FIG.

FIG. 3 is a circuit diagram in FIG.

FIG. 4 is an explanatory diagram showing an example of a strobe charging mode of the specific example in FIG.

FIG. 5 is a control circuit diagram showing an example of a motor drive circuit that performs film feeding, shutter charging, and shutter operation.

6 is a flowchart showing the operation of the camera shown in FIGS. 2 and 3. FIG.

FIG. 7 is a time chart showing the operation of the camera shown in FIGS. 2, 3, and 6 in the shooting preparation mode.

FIG. 8 is a time chart diagram showing an operation in a normal shooting mode.

FIG. 9 is a time chart diagram showing an operation in a self-timer shooting mode.

FIG. 10 is a time chart diagram showing an operation in a self-timer cancel mode.

FIG. 11 is a time chart diagram showing an operation in a final frame shooting mode.

FIG. 12 is a time chart showing the operation when the release button is pressed after the last frame has been shot.

FIG. 13 is a time chart showing the operation in the sky shooting mode.

FIG. 14 is a logical diagram showing setting conditions of a diaphragm, a photographing optical system, and a strobe based on photometry and distance measurement data.

FIG. 15 is a circuit diagram showing a mutual connection relationship of a first release switch, a second release switch, and a self-timer switch.

[Explanation of symbols]

 A Logic control circuit B Distance measuring circuit C Light metering circuit F Strobe circuit SOL1 Aperture control magnet SOL2 Close-up lens control magnet H Trigger control circuit

Continuation of front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location G03B 7/16

Claims (2)

[Claims] 1. A charging means for charging a strobe capacitor, (b) a timer means for measuring a predetermined time when the charging means starts charging, and (c) a charging state of the capacitor is detected. And (d) film exposure means for exposing the film, and (e) the charge state detection means did not complete charging within a predetermined time measured by the timer means. When the thing is detected, while stopping the charging of the capacitor by the charging means,
A camera configured such that film exposure is not performed by the operation of the exposure unit. 2. A first release switch operated by a first press of a release button, and a second release switch operated by a second press of pressing the release button further from the first press, The camera according to claim 1, wherein the charging of the charging means is started based on an operation of the first release switch.