JPS6252289B2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to an AE lock device for a camera.

When taking photographs, there are cases where the main subject and sub-subject are mixed and the main subject is to be placed away from the center of the screen. Measure and store the brightness information of the main subject, then change the camera angle appropriately and take a picture. The above-mentioned mnemonic method is also used when the exposure amount is adapted to a person regardless of the surrounding brightness, such as when photographing a portrait. The exposure information storage circuit used in such cases is what is called an AE lock circuit. On the other hand, single-lens reflex cameras using TTL metering are equipped with a so-called memory switch in order to measure the light before the mirror is raised and store the metered value. Tsute
It was also used as the AE lock circuit. However, with the conventional configuration described above, the AE lock operation can only be performed when the memory switch and AE lock switch is manually pressed, so it is not possible to use the AE lock circuit when shooting using the self-timer. There was a problem.

Another conventional configuration is that the memory switch is turned off when the release button is pressed (in other words, it is turned off manually before the mirror rises, but not before), and when shooting with the self-timer. Some cameras are designed to always perform exposure using the exposure control amount at the time the release button is pressed, but with this configuration, AE is always used when shooting with the self-timer.
The camera user has no choice as to whether or not to use AE lock shooting, and when actually trying to take AE lock shooting, the camera must be pointed at the main subject. When you press the release button, the photometric value is memorized and the self-timer delay operation is started, so it becomes a busy operation to set and correct the camera angle appropriately within the self-timer delay time (about 10 seconds). This makes the camera very difficult to use. Furthermore, when taking self-timer shots without using the AE lock method, the photographer usually sets the camera in a predetermined direction, stands in front of the camera, presses the release button, and then moves to his or her location in the scene. However, if you do this, the metering results will be stored while the photographer is standing in front of the camera and exposure control will be performed, making it impossible to obtain the appropriate exposure. Users must be careful, and it is difficult to avoid mistakes like this just by using instructions that tell you to be careful.

Therefore, an object of the present invention is to
The object of the present invention is to provide a camera in which it is possible to freely select whether or not to perform AE lock photography, and the AE lock operation can be easily performed.

FIG. 1 shows an embodiment of the present invention. 14 is an AE lock signal circuit which outputs an AE lock signal when the AE lock switch is closed by pressing the AE lock button provided on the camera; 11 is a storage means for storing the AE lock signal output from the AE lock signal circuit 14; When the release button is pressed, the output signal of the AE lock signal circuit 14 is read and stored in response to the release signal output from the release signal circuit 13 as the release button is pressed. Also, the signal emitted from this release signal circuit is transmitted to the delay circuit 2.
1, it is also sent to the release control circuit 22, and the release control circuit 22 is activated. The operation of the release control circuit activates the release magnet 23, which starts a series of operations from unlocking the single-lens reflex mirror to starting the shutter front curtain and starting the exposure control circuit. The delay circuit 21 provides a delay time for the self-timer, and the delay time is 0 when the self-timer setting means 20 is not set to use the self-timer.

The memory of the presence of the AE lock signal in the memory means 11 is as follows:
A signal from the exposure end signal transmitting means 16 linked to the shutter mechanism or the manual reset means 17 is erased by being applied as a reset signal to the storage means 11 through the gate 15 (OR gate).

1 is a photometry circuit that performs TTL photometry, and 2 is a memory switch. In normal cameras that do not have an AE lock circuit, the memory switch is linked with the lock release mechanism of the SLR mirror and is opened just before the mirror is raised, and the photometry output is output just before the mirror is raised. It has come to be fixed and memorized. On the other hand, in the present invention, the memory switch 2 receives a signal from the switch means 12 interlocked with the mirror lock release mechanism or the memory switch 1
1 is opened by either the AE lock signal stored in the AE lock signal circuit 14 or a signal from the AE lock signal circuit 14. 10 is an OR gate that passes the above three signals. A memory circuit 3 stores the output of the photometric circuit, and a capacitor is used as a storage element, for example.

In FIG. 1, the release signal circuit 13 and the switch means 12 are shown as having no communication, but this is because they are not electrically connected, and are connected to the magnet 23 by a mechanical chain, so that the two are not related. When the release button is pressed, the release signal circuit 1 is activated.
The storage means 11 is set to AE by the signal output from 3.
The output of the lock signal circuit 14 is read, and this release signal operates the release magnet 23 to release the single-lens reflex mirror, and at the same time, the switch means 12 is operated.

Before the memory switch 2 is turned off, the arithmetic circuit 4 responds to changes in the output of the photometry circuit 1, and changes the maximum aperture value of the photographic lens, Avo, and the film sensitivity.
The exposure time is calculated by reading the output signals of the setting circuits 5, 6, 7, such as Sv, set aperture value Av, etc., and the exposure data is sent to the display means 24 for display. After the memory switch 2 is opened, the exposure time is calculated based on the output of the photometry circuit held in the memory circuit 3, so the exposure time value is fixed. This exposure time value signal is applied to the exposure time control circuit 8. After the release control circuit 22 is activated and mechanical operations such as mirror up and aperture stop are completed, the shutter front curtain is started and the exposure time control circuit 8 is activated.
is activated, and the magnet 9 is activated after a predetermined time according to the exposure time value instructed by the arithmetic circuit 4 to start running the second shutter curtain. Although not shown in FIG. 1, there is a mechanical chain between the exposure time control circuit 8 and the magnet 23, and exposure time control is started when the front curtain of the shutter starts running.

When performing normal photography with the above configuration, since the AE lock signal is not stored in the storage means 11, the release button is pressed and the single-lens reflex mirror is unlocked, and the switch means 12 is activated and the memory switch is activated. Exposure control is performed by the output of the photometry circuit just before the mirror is turned off and the mirror is raised. When using a self-timer, set the self-timer and press the release button to start the self-timer.After a certain period of time, the release control circuit 22 activates the magnet 23, which releases the mirror lock and turns off the memory switch 2. be done. For AE lock shooting, press the AE lock button and the release button at the same time. Then, the AE lock signal is stored in the storage means 11, and the memory switch 2 is turned off by this storage output, so that the photometric value is fixed before the mirror is raised. After that, even if you let go of the AE lock button, the AE lock signal remains in the storage means, so memory switch 2 remains off, and the release control circuit is activated by the release signal, raising the mirror and opening the shutter front curtain. is released, the arithmetic circuit calculates the exposure time based on the previously fixed photometric information, and provides the exposure information to the exposure time control circuit 8, and exposure control is performed using this information. If you want to perform AE lock when using the self-timer, set the self-timer, point the camera in the direction you want to meter, press the metering switch, and then press the AE lock button to turn off switch 2 and perform AE lock. be exposed. In this state, even if you change the angle and decide on the composition, the memory contents will be retained as long as the AE lock button is pressed. The next time the release button is pressed, the self-timer starts. At the same time, the AE lock signal is stored in the storage means 11 by this release signal, and after that, you can release the AE lock button.When the self-timer clocks on, the exposure time is controlled based on the AE-locked photometric value. will be held.

FIG. 2 shows a specific configuration of the main parts of the apparatus shown in FIG. The release signal circuit 13 consists of a switch 36 that is turned on when the release button is pressed and a resistor, and the AE lock signal circuit is also composed of a resistor.
Switch 4 that is turned on when the AE lock button is pressed
It is closer to 0 and resistance. The storage means 11 is mainly composed of a flip-flop 31, and its set state is a state in which the AE lock signal is stored. The set input terminal of the flip-flop 31 receives, via an AND gate 32, a high level signal due to the AE lock signal circuit being switched on, a high level signal due to the release signal circuit being turned on by the switch 36, and a switch 37 that is turned on when the shutter charge is completed.
A signal formed by ANDing three high-level signals generated by turning on is applied.
The set output of flip-flop 31 is sent to memory switch 2 via OR gate 10 to turn it off. There is a signal path from the AE lock signal circuit 14 directly to the memory switch means 2 via the OR gate 10, because when the AE lock button is pressed, the memory switch is immediately turned off, and the photometric value is fixed at the timing when the AE lock button is pressed. This is to ensure that. When the release button is pressed while holding down the AE lock button, the AE lock signal is held in the storage means 11. 33 is a gate for inputting a signal for setting the flip-flop 31 to the reset terminal R; a signal for setting the flip-flop 31 (signal from the AND gate 32);
In this state, a signal from circuit 16 or 17 is applied to the reset terminal of flip-flop 31 through gate 33. The circuit 16 consists of a switch 39 that is closed when exposure is completed and a resistor, and the circuit 17 consists of a switch 28 and a resistor that is turned on when the self-timer is reset, and is used when it is desired to cancel the self-timer setting midway. The switch means 12 is a switch 4 that is closed by the operation of the unlocking mechanism of the single-lens reflex mirror.
1 and a resistor, which opens the memory switch 2 just before the mirror is raised in the case of normal photography.

FIG. 3 shows another embodiment of the present invention.
Parts corresponding to those in the illustrated embodiment are given the same numbers. The difference between this embodiment and the embodiment shown in FIG. 1 is that by setting the self-timer setting means 20 to the self-timer use side, the set signal is sent to the storage means 11 via the AND gate 50, and the AE lock signal is set. The point is that the output of the circuit 14 is read. This is because the AE lock signal needs to be stored mainly when the self-timer is used, so the AE lock signal is stored only when the self-timer is used. In AE lock shooting when not using the self-timer
The AE lock signal is sent directly to the memory switch 2 through the gate 10.

FIG. 4 shows an embodiment of the present invention using mechanical means, and shows the storage means 11 in the above embodiment.
is used as a mechanical storage means. 100 is the operation knob of the self-timer setting means, and 108 is the operation knob of the self-timer setting means.
This is the AE lock button. AE lock button 108
is pulled upward by a spring 106, and 107
is a stopper that limits upward movement of the AE lock button 108. When the self-timer is not used, each member is in the positional relationship shown, and when the AE lock button is pressed, the switch 104 (switch 40 in FIG. 2) of the AE lock signal circuit is closed and the memory switch is turned off. When using the self-timer, turn the operating knob 100 in the direction of the arrow to the dotted line position. This action charges the self-timer and also rotates the lever 102 coaxial with the operating knob 100 in the same direction. Operation knob 1
Another lever 101 is rotatably fitted to the shaft of 00, and this lever is activated by a spring 105.
The lock button 108 is biased toward the body 103, but normally, its rotation is prevented by the rising portion of the lever 102 and is separated from the body 103. When the self-timer is used, the lever 102 moves away in the direction of the arrow as described above, so the lever 101 is moved by the spring 105.
The body 103 of the AE lock button 108 is pulled by
comes into contact with. When the AE lock button is pressed in this state, the memory switch is turned off and the metering value is fixed as described above, and the lever 101 is moved by the spring 1.
05, it falls into the groove 109 cut in the body of the AE lock button. Therefore, from now on, press AE lock button 1.
Even if you let go of 08, the AE lock button remains on lever 10.
1, it is locked in the pressed position and cannot return upward, meaning that the AE lock signal is stored. To release this lock, the operating knob 100 must be returned to the position shown by the solid line in the figure. In this embodiment, during normal shooting, the AE lock is activated only when the AE lock button is pressed, and the AE lock switch 10
4 (switch 40 in Figure 2) is no longer forgotten, and when using the self-timer, you can choose between AE lock shooting or normal shooting. Since the operating knob of the setting means is turned back, it is possible to prevent forgetting to reset the self-timer setting.

The device of the present invention has the above-mentioned configuration and can not only perform AE lock photography without using a self-timer.
Even when using the self-timer, it is possible to arbitrarily select whether or not to use AE lock photography, and there is no chance of failures such as forgetting to turn off the AE lock switch (40 in Figure 2, 104 in Figure 4), and the appropriate AE can be set. A camera with a lock circuit can be provided.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of an apparatus according to an embodiment of the present invention, FIG. 2 is a circuit diagram showing the main parts of the above embodiment, and FIG. 3 is a block diagram showing the main parts of another embodiment of the invention. 4 are perspective views showing essential parts of another embodiment of the present invention. 108: Manual operation member, 14: AE lock signal output means, 20: Shooting mode setting means, 13: Release signal output means, 11: AE lock signal storage means, 1: Photometry means, 3: Photometry output holding means, 5
-9: Exposure control means, 21-23: Release means, 12: Inhibition signal output means, 2, 10: Inhibition means.

Claims (1)

[Scope of Claims] 1. A manual operation member that is manually operated independently of the photographing operation, an AE lock signal output means that outputs an AE lock signal while the manual operation member is being manually operated, and a self-timer photographing system. shooting mode setting means for selectively setting a mode and a normal shooting mode; a release signal outputting means for outputting a release signal in response to a shooting operation; and a release signal outputting means for outputting a release signal when the release signal is output. If the AE lock signal is output, the AE lock signal will be memorized.
an AE lock signal storage means, a photometry means, a photometry output holding means for holding the photometry output of the photometry means, an exposure control means for controlling exposure based on the output held by the holding means, and a self-timer shooting mode. A release means that starts the exposure control operation after a predetermined self-timer time delay based on the release signal when setting, and in response to the release signal when setting the normal shooting mode, and a prohibition related to the start of the exposure control operation. prohibition signal output means for outputting a signal;
Based on the AE lock signal output from the AE lock signal output means, based on the prohibition signal output from the prohibition signal output means, or based on the storage output when the AE lock signal is stored in the storage means. 1. An AE locking device for a camera, comprising: prohibiting means for prohibiting transmission of photometric output from the photometric means to the holding means. 2. The AE lock device for a camera according to claim 1, wherein the storage means includes gate means for permitting storage of the AE lock signal based on the release signal only when the self-timer shooting mode is set.