JPS6238693B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a warning erroneous display prevention circuit in a programmable electric shutter linked to a light receiving aperture.

A programmable electric shutter linked to the light receiving aperture is already known, in which the light receiving window is opened in advance for a warning operation, and after the light receiving window is shielded, the light receiving aperture is also opened in conjunction with the opening of the shutter blades that also serve as aperture blades. However, in this type of programmed electric shutter, if the light receiving window is blocked, the same condition as the low brightness warning occurs, resulting in an erroneous display.

The present invention eliminates the drawbacks of the conventional circuit described above, and extracts an electric signal corresponding to the attenuation of the light amount due to the blocking of the light receiving window and latches the warning circuit to a disabled state to prevent erroneous display. The present invention provides a circuit for preventing erroneous warning display in a programmable electric shutter linked to a light receiving aperture.

Embodiments of the present invention will be described below based on the drawings.

First, the structure of the shutter mechanism shown in FIGS. 1 to 9 will be explained. 1 is a shutter plate which forms an exposure opening 1a and a light receiving window 1b, and has pins 1c to 1i implanted therein. Reference numeral 2 denotes a release plate, which has long grooves 2a, 2b and a bend 2c that fit with pins 1c, 1d, has a pin 2d planted therein, and is given an upward movement habit by a spring 3. 4 is a closing drive plate having long grooves 4a, 4b that fit with pins 1c, 1e, arms 4c, 4d, slope 4e,
While forming a flat surface 4f, a pin 4g is installed, and a rightward movement habit is given by a spring 5 applied to the pins 1e and 4g. Reference numeral 6 denotes a leaf spring member, which is fixed on the closing drive plate 4 with screws 6a and 6b, and has bends 6c and 6d at both ends that protrude toward the back side of the closing drive plate 4, respectively, as shown in FIG. It has 6c' and 6d'. The bend 6c is adapted to engage with the bend 2c of the release plate 2. 7 is a shutter release lever pivotally connected to a shaft 8, which forms arms 7a, 7b and another arm 7c that can engage with a pin 1f, and a tip 7a' of the arm 7a bends 6.
The arm 7a is bent so as to be located within the locus of motion of d, and a spring 9 imparts dextrorotation so that the arm 7a engages the pin 1f. 10 is the axis 11
The opening/closing lever is pivotally connected to the opening/closing lever, has an arm 10a that can engage with the arm 7c, and has a non-conductive pin 1.
0b, a protrusion 10c, and pins 10d to 10g are implanted. A conductive ring 12 is fitted onto the pin 10b. A spring 13 also serves as a lead wire, and is hung between the pin 1i and the conductive ring 12, giving levorotation to the opening/closing lever 10. Arm 4 of closing drive plate 4
d indicates the conductive ring 12 of the opening/closing lever 10 and the protrusion 10c.
The arm 4d and the conductive ring 12 constitute a synchro switch. 14 is a shutter blade that also serves as an aperture blade, one of which is shown in a set of two; pin 1g;
Long grooves 14a, 14b and pin 10d that fit with 1h
the long groove 14c that fits with the shutter opening 14;
d, an opening 14e for introducing exposure warning information, and an opening 14f for introducing exposure information. The other shutter blades (not shown) have their exposure warning information introduction openings aligned with the exposure warning information introduction openings 14e of the shutter blade 14; It is formed symmetrically with the long groove 1.
A long groove corresponding to 4b is fitted with the pin 10e. The light-receiving element is arranged corresponding to the light-receiving window 1b so as to be able to receive field light through the aperture 14e or 14f. Reference numeral 15 denotes an iron piece lever pivotally connected to a shaft 16, which has a bend 15a capable of locking the arm 4c and another bend 15b, and has a pin 15c implanted therein. Reference numeral 17 denotes an iron piece, which is pivotally mounted on the bend 15b by a pin 18. Reference numeral 19 denotes a hold lever pivotally connected to the shaft 16, and a pin 1 that can engage the slope 4e and the flat surface 4f.
9a is implanted, and an arm 19b that engages with the pin 15c is formed, and a spring 20 provides dextrorotation. 21 is the iron piece spring, iron piece lever 1
5 and the hold lever 19, and acts to press the pins 15c and 19b into contact with each other.
Reference numeral 22 designates a flash opening lever pivotally connected to a shaft 23, which forms a cam surface 22a on which the pin 10g can come into contact, and has a pin 22b installed therein which is operated by a distance adjusting member (not shown). spring 24
gives it dextrorotation. Note that there is a top plate and a base plate (not shown) above and below the shutter plate 1, the shutter blade 14 is arranged between the base plate and the shutter plate 1, and the shutter opening lever 22 is located at the bottom. It is arranged on the back side of the main plate, and other members are arranged between the shutter plate 1 and the upper main plate. Therefore, the pins 10d and 10e of the opening/closing lever 10 penetrate the shutter plate 1 and protrude to the back side thereof, and the pin 10g further protrudes to the back side of the base plate. Incidentally, long grooves are formed in the shutter plate 1 and the base plate to allow movement of each pin, but they are omitted in the drawing. Further, the shutter plate 1, the closing drive plate 4, and the opening/closing lever 10 may be integrally molded of resin or the like. In that case, a conductive piece is attached to the surface of the arm 4d of the closing drive plate 4 that can engage the conductive ring 12. It is necessary to maintain the electrical connection by pasting the Furthermore, 102, 114, and 117 are switches and electromagnets of a control circuit that will be described later, and the electromagnet 117 is supported by the back side of the upper plate or a part (not shown) standing up from the shutter plate 1, so that the electromagnet 117 is connected to the surface of the shutter plate 1. It is placed so as to be lifted from the ground and to face the iron piece 17.

Next, the configuration of the shutter control circuit shown in FIG. 18 will be explained in relation to the shutter mechanism. Reference numeral 101 is a power supply battery, the (-) pole of which is grounded. 102
is a power switch, which is installed opposite pin 2d of release plate 2. 103 is a light receiving element such as a photovoltaic element, the anode of which is grounded, and the cathode of which is connected to the amplifier circuit 1.
It is connected to the inverting input terminal (-) of 04. 1
A logarithmic compression diode 05 has a cathode connected to the inverting input terminal (-) and an anode connected to the output terminal of the amplifier circuit 104. 10
6 is a reference voltage circuit. 107 is a window comparator, whose inverting input terminal (-) 107a is connected to the output terminal of the amplifier circuit 104, and its non-inverting input terminals (+) 107b and 107c are connected to the output terminals 106a and 106b of the reference voltage circuit 106, respectively. There is. 108 and 109 are LEDs (lamp etc. can be used) for high brightness warning and low brightness warning, and output terminals 107d, 10 of the window comparator 107
7e and the power supply battery 10 via the power switch 102.
1 (+) pole. Reference numeral 110 denotes a capacitor for controlling exposure time, one end of which is connected to the (+) pole of the power supply battery 101 via the power switch 102, and the other end connected to the collector/emitter of the logarithmic expansion transistor 112 or the resistor 113 by the changeover switch 111. It is grounded through either one of the two. The base of the transistor 112 is the amplifier circuit 1
It is connected to the output terminal of 04. 114 is a switch for starting exposure time measurement, and a capacitor 110
are connected in parallel to each other, and are provided opposite to the pin 10f of the opening/closing lever 10. A comparator 115 has a non-inverting input terminal (+) connected to the output terminal 106c of the reference voltage circuit 106, and an inverting input terminal (-) connected to the other end of the capacitor 110. 116
is an amplifier circuit, which is connected to the output terminal of the comparator 115. 117 is an electromagnet and amplifier circuit 11
6 and a power supply battery 101 via a power switch 102.
It is connected between the (+) pole of 118 is an amplifier circuit whose non-inverting input terminal (+) is connected to the output terminal 106d of the reference voltage circuit 106, and whose output terminal is connected to the non-inverting input terminal (+) of the amplifier circuit 104. 119 is a variable resistor, and the amplifier circuit 11
It is connected between the output terminal of 8 and the inverting input terminal (-). 120 is a resistor, one end of which is connected to the amplifier circuit 1
It is connected to the connection point between the inverting input terminal (-) of No. 18 and the variable resistor 119, and the other end is grounded.

Next, the shutter mechanism shown in Figures 1 to 9 and the shutter mechanism shown in Figure 18
The operation of this embodiment will be explained with reference to the shutter control circuit shown in the figure. First, the warning operation will be described. When the release plate 2 is pushed down against the tension of the spring 3, the power switch 1 is turned off by the displacement of the pin 2d.
02 is closed and voltage is supplied to each part of the circuit. At this time, the light receiving element 103 is irradiated with field light passing through the light receiving window 1b and the exposure warning information introduction opening 14e, so a photocurrent i is generated.
The signal is amplified by the amplifier circuit 104. The amplifier circuit 104 has an output terminal and an inverting input terminal (-).
Since the logarithmic compression diode 105 is connected between the input terminal and the output terminal to provide feedback, a compression voltage proportional to the logarithm of the photocurrent i is generated at its output terminal, and this voltage is applied to the inverting input terminal of the window comparator 107 (- ) 107a. Here, if this voltage is higher than the high-intensity warning reference voltage given from the output terminal 106a of the reference voltage circuit 106 to the non-inverting input terminal (+) 107b, only the LED 108 connected to the output terminal 107b lights up, and the output terminal 106b is connected to the non-inverting input terminal (+).
If it is lower than the low brightness warning reference voltage given to 107c, it is connected to output terminal 107e.
When only LED 109 lights up and proper exposure between both reference voltages is possible, LED 109 lights up.
8 and 109 do not light up. Note that the low brightness warning operation signal is inverted inside the window comparator 107.

Next, let's talk about automatic shooting. In this case, the changeover switch 111 is connected to the terminal 111a side by a switching member (not shown) between automatic photography and flash photography, and the flash opening lever 2 is connected to the terminal 111a side.
2 remains in the position shown in FIG. 1 without being operated by the distance adjusting member, and the cam surface 22a is out of the movement trajectory of the pin 10g of the opening/closing lever 10.
Note that this switching mechanism can also be linked to the operation of attaching the flash device to the camera or the operation of hopping up the flash device from the camera. First, when the power switch 102 is closed, the switch 114 is closed and the inverting input terminal (-) of the comparator 115 is raised to the (+) pole level of the power battery 101, so that the output terminal is Since it is placed at the "L" level, the electromagnet 117 is energized from the time it is closed. Therefore, the iron piece lever 15 is held in the state shown in FIG. 1 by the iron piece 17 being attracted to the electromagnet 117. When the release lever 2 is further pushed down from the warning operation stage, the bend 2c is removed from the bend 6c of the leaf spring member 6. As a result, the closing drive plate 4 on which the leaf spring member 6 is mounted is moved to the right by the tension of the spring 5. As shown in FIG. 2, the closing drive plate 4 is temporarily stopped with the arm 4c in contact with the bend 15a of the iron piece lever 15, but in the process up to that point, the slope 4e pushes the pin 19a. The iron piece spring 21 is charged by turning the hold lever 19 to the left while resisting the tension of the spring 20. Also, the bending 6c of the leaf spring member 6 is caused by the release lever 2
The release lever 2 is now within the return trajectory of the bend 2c, and the release lever 2 is prevented from returning, and the power switch 1 is turned off.
02 is maintained in the closed state. On the other hand, the bend 6d pushes the bend 7a' to rotate the shutter release lever 7 to the left against the tension of the spring 9. As the lever 7 rotates to the left, the arm 7c comes off from the arm 10a, so the opening/closing lever 10 rotates to the left due to the tension of the spring 13, and the pin 1
0d (10e) to move the shutter blade 14 to the right (other shutter blades not shown are to the left) and open the switch 114 by displacing the pin 10f. As the shutter blade 14 moves, the opening 14e is first displaced and the light receiving window 1b is temporarily moved.
Since the switch 114 is already open at this point, charging of the capacitor 110 begins with a current corresponding to the dark current of the light receiving element 103. Subsequently, the exposure information introduction opening 14f starts opening the light receiving window 1b first, and a little later the shutter opening 14d opens the exposure opening 1a.
Here, the so-called mechanical delay is corrected by charging the capacitor 110 due to the dark current and the prior opening of the light receiving window 1b. And the shutter opening 14d
In response to the increase in the aperture 14f in conjunction with the increase in , the light irradiating the light receiving element 103 gradually increases, a current proportional to the photocurrent flows into the collector of the transistor 112, the capacitor 110 is further charged, and the voltage of the comparator 115 increases. The potential of the inverting input terminal (-) gradually decreases. Here, when the field light is doubled, the photocurrent is doubled, and when the field light is quadrupled, the photocurrent is quadrupled, so the so-called gamma characteristic is "1". When using an element, the collector current of the transistor 112 is proportional to the photocurrent, so
Charging the capacitor 110 means integrating the amount of light. Furthermore, since the apertures 14d and 14f are formed on the same member and have substantially similar shapes, it can be said that the integrated amount of photocurrent and the amount of exposure on the image plane are in a directly proportional relationship. Therefore, if a constant potential is applied from the output terminal 106c of the reference voltage circuit 106 to the non-inverting input terminal (+) of the comparator 115, this potential will provide a constant reference for the image plane exposure amount, and the light The amount of exposure can be controlled by comparing the integrated amount of current with the potential corresponding to it. Then, as the capacitor 110 is charged, the potential of the inverting input terminal (-) becomes lower than the potential of the non-inverting input terminal (+), the comparator 115 is inverted and the output terminal becomes "H" level. , the electromagnet 117 is demagnetized. As a result, the iron piece lever 15 is rotated to the left by the charged iron piece spring 21, and the bend 15a is removed from the arm 4c. Therefore, the closing drive lever 4 is further moved to the right by the tension of the spring 5, as shown in FIG. By this movement to the right, the arm 4d first contacts the conductive ring 12 and rotates the opening/closing lever 10 to the right against the tension of the spring 13, and from the middle, the non-conductive protrusion 10c replaces the conductive ring 12. The opening/closing lever 10 is rotated to the right to the final range. Therefore, the shutter blade 14 is
The exposure opening 1 by the opening 14d corresponds to the time when the conductive ring 12 is pushed by the arm 4d according to the field light.
Exposure opening 1 during the opening of a or from the fully opened state
Close a. Also, switch 114 is connected to pin 10.
Since the capacitor 110 is pushed by f and closed, the capacitor 110
charge is discharged. Furthermore, since the bend 6c of the leaf spring member 6 is removed from the bend 2c, the release lever 2 returns upward due to the tension of the spring 3, and the pin 2d
The power switch 102 is opened. On the other hand, since the bend 6d separates from the bend 7a', the shutter release lever 7 rotates clockwise due to the tension of the spring 9 until the arm 7a abuts the pin 1f, and the arm 7c moves within the left rotation trajectory of the arm 10a of the opening/closing lever 10. Coming. The shutter mechanism is set by moving the closing drive plate 4 to the left against the tension of the spring 5. That is, in this leftward movement process, the leaf spring member 6
As shown in FIG. 4, the slope 6c' of the bend 6c climbs over the bend 2c of the release lever 2, and the other bend 6d
Bending the shutter release lever 7 at the slope 6d'
Climb over a', overrun, return and bend 6c
engages the bend 2c. On the other hand, due to the return of the closing drive plate 4, the pin 19a is moved from the flat surface 4f to the slope 4e.
is released, the hold lever 19 rotates to the right together with the iron piece lever 15 due to the tension of the spring 20, the bend 15a faces within the locus of movement of the arm 4c, and the iron piece 17 comes into contact with the electromagnet 117. As a result, all the members return to the state shown in FIG.

Next, let's talk about flash photography. By switching to flash photography, the changeover switch 11
1 is connected to the terminal 111b, that is, connected to the resistor 113 instead of the transistor 112, and
The flash opening lever 22 is operated via the pin 22b in conjunction with the distance adjustment, and is rotated to the left against the tension of the spring 24 in accordance with the amount of adjustment. Assuming that the flash opening lever 22 has been rotated counterclockwise to the state shown in FIG. 5 by the distance adjustment described above, the opening/closing lever 10 is moved so that the pin 10g is moved to the cam surface 22a by the shutter release operation described above.
Turn the shutter blade 14 to the left until it touches the shutter blade 14.
The opening 14d opens the exposure opening 1a to a size corresponding to the distance. And capacitor 1
10 and resistor 113, the electromagnet 11
7 is demagnetized, the closing drive plate 4 moves to the right and the exposure opening 1a is closed by the shutter blade 14 in the same manner as described above. Further, as shown in FIG. 6, the synchro switch is closed when the arm 4d that starts this closing operation comes into contact with the conductive ring 12, and the flash device emits light at its maximum opening point. As shown in FIG. 3, at the final point of the closing operation, the arm 4d is separated from the conductive ring 12 and engages the non-conductive protrusion 10c, so that the flash device does not erroneously emit light.

In FIG. 7, the light emission timing of the flash device is changed to the time when the opening/closing lever 10 comes into contact with the flash opening lever 22. In FIG. That is, in the opening/closing lever 10, the pin 10b is removed and the conductive ring 1 is removed.
2' is fitted onto the pin 10g, one end of the spring 13 is hung on the conductive ring 12', and the flash opening lever 22 is made a conductive member, and the synchro switch is activated by the cam surface 22a and the conductive ring 12'. It is composed of Moreover, FIGS. 8 and 9 show changes to a flash photography mechanism that allows daytime synchronized photography. That is, in the opening/closing lever 10,
A conductive ring 12' is also fitted to the pin 10g, and a spring 13' serving as a lead wire is also hung between the conductive ring 12' and the pin 1j. And conductive ring 12
and synchro switch by arm 4d, and conductive ring 1
2' and a synchro switch formed by the cam surface 22a are connected in parallel, the resistor 113 is not provided, and the exposure time is automatically controlled by the light receiving element 103 according to the field light. Therefore, when the aperture amount determined by the distance adjustment is smaller than the aperture amount determined by the field light, the conductive ring 12' comes into contact with the cam surface 22a, as shown in FIG. At that point, the flash device emits light, and the exposure time is determined by the natural light and the flash device's auxiliary light. In the opposite case, as shown in FIG. 9, the flash device emits light due to the contact of the arm 4d with the conductive ring 12 before the conductive ring 12' contacts the cam surface 22a. In this way, the shutter aperture gives priority to a small aperture depending on field light or distance adjustment.

Although FIG. 6 has been described as showing the operating state after FIG. 5, it is also possible to perform synchronized photography during the daytime even if the device has a synchronized switch consisting of the arm 4d and the conductive ring 12. In this explanation, Fig. 5 shows the state at the time when the shutter aperture is determined according to the distance, and Fig. 6 shows the state when the shutter aperture is determined according to the field light. . In this case, the flash device emits light at the time when the shutter blade 14 starts to close, but the small aperture is still prioritized.
Further, the amount of displacement of the flash opening lever 22 may be controlled by not only distance information but also guide number information and/or composite information of film sensitivity information. Furthermore, in the control circuit of FIG. 18, when the variable resistor 119 is changed, the potential of the non-inverting input terminal (+) of the amplifier circuit 104 is changed, and the voltage of the output terminal can be shifted. Therefore, the variable resistor 119 allows photographing information such as film sensitivity and/or F value to be electrically introduced.

Next, with reference to FIG. 19, a shutter control circuit incorporating a circuit that prevents erroneous warning display and a long time limit circuit will be described. A comparator 121 has a non-inverting input terminal (+) connected to the output terminal of the amplifier circuit 104 and an inverting input terminal (-) connected to the output terminal 106e of the reference voltage circuit 106. 122, 123, and 124 are capacitors, resistors, and inverters that constitute a differential circuit; one end of the capacitor 122 is connected to the output terminal of the comparator 121, and one end of the resistor 123 is connected to the (+) terminal of the power supply battery 101 via the power switch 102. connected to the pole. 125 is a latch circuit using a circuit such as a flip-flop, the set input terminal (S) is connected to the output terminal of the inverter 124 in the differential circuit, and the inverted output terminal (-) is connected to the gate input terminal (G) of the window comparator 107. )
107f. 126 and 127 are capacitors and resistors that constitute a delay circuit for long time regulation, one end of the capacitor 126 is connected to the (+) pole of the power battery 101 via the power switch 102, and one end of the resistor 127 is grounded. ing.
A transistor 128 is connected in parallel to the capacitor 126, and its base is connected to the non-inverting output terminal (Q) of the latch circuit 125. 129 is a comparator, and the inverting input terminal (-) is connected to capacitor 1.
26 and the resistor 127, and the non-inverting input terminal (+) is the output terminal 1 of the reference voltage circuit 106.
Connected to 06f. 130 is an OR gate, one input terminal (a) is connected to the output terminal of the comparator 129, the other input terminal (b) is connected to the output terminal of the comparator 115, and the output terminal is connected to the electromagnet through the amplifier circuit 116. 117.

Next, the operation of this embodiment will be described. Immediately before the above-mentioned opening operation of the shutter blade 14, the light receiving element 1
03 is temporarily shielded from field light. This state is the same as a low brightness warning, and in the shutter control circuit shown in FIG.
When the output voltage of the comparator 121 reaches a voltage corresponding to the dark current in the dark state, the potential of the non-inverting input terminal (+) of the comparator 121 changes to the inverting input terminal (+) given by the output terminal 106e of the reference voltage circuit 106. -), the output terminal of the comparator 121 is inverted from the "H" level to the "L" level. This reversal generates a negative differential pulse at the connection point between the capacitor 122 and the resistor 123 in the differential circuit, and as a result, the inverter 12
A positive pulse is generated at the output terminal of 4, the latch circuit 125 is set, and the inverted output terminal (-) is inverted from the "H" level to the "L" level. Since this "L" level signal is given to the gate input terminal (G) of the window comparator 107, the output terminals 107d, 1 of the comparator 107
07e are both placed at the "H" level, therefore,
The LEDs 108 and 109 can no longer be lit. On the other hand, when the non-inverting output terminal (+) is inverted to the "H" level by the setting of the latch circuit 125, the transistor 128 is cut off, so the capacitor 12
6 is charged according to the value of the resistor 127. In the initial state, the output terminals of comparators 115 and 129 are both at "L" level, and the output terminal of OR gate 130 is at "L" level.
Although the electromagnet 117 is energized, the transistor 128 is cut off and the switch 11 is activated as described above.
When the output terminal of one of the comparators 115 or 129 is inverted to the "H" level due to the opening of 4, the output terminal of the OR gate 130 is inverted to the "H" level, so the electromagnet 117 is demagnetized, and at that point the shutter blade is 14 will be closed. That is, the longest exposure time is the capacitor 126 and the resistor 1.
The maximum time is, for example, 10 seconds, or it can be set to 1/30 second, 1/15 second, etc. to prevent camera shake, and the resistor 127 is a variable resistor. Alternatively, it is more effective to use a switching resistor. If the maximum time is set to 1/30 second, 1/15 second, etc., the shutter control circuit can be made effective even during flash photography.

Next, referring to FIG. 20, a shutter control circuit in which the start of exposure time measurement is also electrically controlled will be described. 131 and 132 are a capacitor and a variable resistor that constitute the delay circuit for adjustment, one end of the capacitor 131 is connected to the (+) pole of the power battery 101 via the power switch 102, and one end of the variable resistor 132 is grounded. ing. 133 is a transistor connected in parallel to the capacitor 131;
The base is connected to the non-inverting output terminal () of the latch circuit 125. 134 is a comparator, the inverting input terminal (-) is connected to the connection point of the capacitor 131 and the variable resistor 132, and the non-inverting input terminal (+) is connected to the output terminal 106 of the reference voltage circuit 106.
connected to g. A transistor 135 is connected in parallel to the capacitor 110 in place of the switch 114, and its base is connected to the output terminal of the comparator 134 together with the base of the transistor 128. 136 is a variable resistor, one end of which is connected to an input terminal 106h capable of adjusting the voltage of the output terminal 106g of the reference voltage circuit 106, and the other end is grounded. In the initial state, the non-inverting output terminal ( ) of the latch circuit 125 is at the "L" level and the transistor 133 is conductive. Therefore, the inverting input terminal (-) of the comparator 134 is at the "H" level, the output terminal is at the "L" level, and the transistors 128 and 135 are both conductive. As mentioned above, when the latch circuit 125 is set and the non-inverting output terminal () is inverted to the "H" level, the transistor 133 is cut off.
Charging of the capacitor 131 is started according to the value of the variable resistor 132. And the inverting input terminal (-)
The potential at the output terminal 106 of the reference voltage circuit 106
Non-inverting input terminal (+) given by g
When the potential becomes lower than the potential of the comparator 134, the comparator 134 is inverted and the output terminal becomes "H" level. As a result, transistors 128 and 135 are cut off, and measurement of the maximum time regulation and exposure time control delay circuits is started, and the subsequent operation is the same as that of the shutter control circuit shown in FIG. 19 described above. Therefore, by changing the time in seconds until the comparator 134 is reversed by setting the variable resistor 132, the timing can be adjusted to match the relationship between the shutter blade opening start and the shutter blade closing timing, which has a mechanical delay. In particular, the measurement start timing of the delay circuit for controlling exposure time can be easily adjusted. Further, the variable resistor 132 connected to the inverting input terminal (-) of the comparator 134 is fixed, and the variable resistor 136 of the reference voltage circuit 106 is varied to change the reference voltage at the non-inverting input terminal (+) of the comparator 134. Similar adjustments can also be made in this manner.

Next, a shutter mechanism including a self-timer control element will be described with reference to FIGS. 10 to 13, and its shutter control circuit will be described with reference to FIG. 21. The closing drive plate 4 further forms a hook 4h and has a pin 4i implanted therein. Iron piece lever 15 is pin 1
Bend 15d is formed in place of bend 5c, and bend 15d
is engaged with the arm 19b of the hold lever 19 on one side. 25 is a timer lever pivotally connected to the shaft 16, and has a bent 25a that can be engaged with the hook 4h.
and an arm 25b that engages with the other side of the bend 15d, and a spring 26 that is somewhat stronger than the spring 20 provides levorotation. As a result, in the initial state, even if the iron piece lever 15 is turned left and the electromagnet 117 is excited, the iron piece 17 is not attracted, and one end of the electromagnet 117 is connected to the resistor 137 instead of the amplifier circuit 116. The output terminal 115a of the comparator 115 is connected to the output terminal 115a of the comparator 115 via. Therefore, when the power switch 102 is simply closed, the current flowing through the electromagnet 117 is limited by the resistor 137 and is therefore very small, and its excitation force is weak. 138 and 139 are resistors and capacitors that constitute a delay circuit for the self-timer, and one end of the resistor 138 is connected to the power switch 10.
2 to the (+) pole of the power supply battery 101, and one end of the capacitor 139 is grounded.
Reference numeral 140 denotes a switch for starting the measurement of the delay circuit, which is connected in parallel to the capacitor 139 and placed opposite to the pin 4i of the closing drive plate 4. Reference numerals 141 and 142 indicate a self-timer set/reset switch and a resistor having an extremely small value, the series circuit of which is connected in parallel to the resistor 138. 14
3 is a comparator whose inverting input terminal (-) is connected to the output terminal 106i of the reference voltage circuit 106;
A non-inverting input terminal (+) is connected to a connection point between resistor 138 and capacitor 139. 144,1
45 and 146 are a capacitor, a resistor, and an inverter that constitute a differentiating circuit, one end of the capacitor 144 being connected to the output terminal 143a of the comparator 143, and one end of the resistor 145 being grounded.
148 is a current amplification circuit whose input terminal is connected to the output terminal of the inverter 146 and whose output terminal is connected to one end of the electromagnet 117. 149 is a NAND gate whose input terminals are non-inverting output terminals 115b and 143b of comparators 115 and 143, respectively.
It is connected to the. 150, 151, and 152 are capacitors, resistors, and inverters that constitute a differential circuit; one end of the capacitor 150 is connected to the output terminal of the NAND gate 149, and one end of the resistor 151 is connected to the (+) terminal of the power supply battery 101 via the power switch 102. connected to the pole. 153 is an SCR whose gate is connected to the output terminal of the inverter 152 and grounded via a resistor 154, and whose cathode is grounded. 155 is an electroflash trigger circuit, which is connected between the anode and cathode of SCR 153.

Next, the operation of this embodiment will be explained. In the case of self-timer photography, for example, the dial is set to the self-timer position and the switch 141 is opened. The closing drive plate 4 moves to the right as the release lever 2 is operated, but the drive plate 4 is temporarily stopped at the initial position where the hook 4h is locked to the bent 25a of the timer lever 25, as shown in FIG. Ru. The switch 140 is opened by the displacement of the pin 4i as the closing drive plate 4 moves, and charging of the capacitor 139 via the resistor 138 is started.
Also in this state, the release lever 2 is prevented from returning, and the power switch 102 is maintained in the closed state. As the capacitor 139 is charged, the comparator 143 detects that the potential of the non-inverting input terminal (+) reaches the output terminal 1 of the reference voltage circuit 106 after 10 seconds, for example, as a self-timer operation.
The potential of the inverting input terminal (-) applied from 06i becomes higher and is inverted, and the output terminal 143a
becomes "H" level. As a result, a positive differential pulse is generated at the connection point between the capacitor 144 and the resistor 145 in the differentiating circuit, and a negative pulse is generated at the output terminal of the inverter 146. A negative pulse is applied to one end of the electromagnet 117, and although a small current was being passed through the electromagnet 117, a large current is instantaneously passed through the electromagnet 117, and the magnetic force increases and attracts the iron piece 17, causing the iron piece lever 15, The timer lever 25 is rotated to the right against the tension of the spring 26. Furthermore, after this suction operation,
The electromagnet 117 is able to attract and hold the iron piece 17, although the pulse is demagnetized and the energization becomes a minute current again. After this, the steps shown in FIGS. 12 and 13, which are similar to those shown in FIGS. 2 and 3 above, are carried out.
The shutter blade 14 is opened and closed.

Furthermore, during normal shooting without using the self-timer, the switch 141 is closed and a resistor 142 with a small value is connected in parallel to the resistor 138.
The combined resistance is becoming smaller. Therefore, the delay time is extremely short, and the shutter opening/closing operation is performed virtually immediately. Note that the delay time is 0
However, by allowing a certain amount of time, the operation of the mirror and/or automatic aperture mechanism can be adjusted when applied to a single-lens reflex camera, or when applied to a camera equipped with an automatic focus adjustment mechanism. There is an effect that can be used to absorb the adjustment mechanism's adjustment mechanism.

Furthermore, this shutter mechanism also includes the arm 4d of the closing drive plate 4 and the conductive ring 12 on the opening/closing lever 10, as described above.
This shutter control circuit also incorporates an electrical synchro switch. That is, Nand Gate 149
When the comparator 143 is inverted at the end of the self-timer operation, the non-inverted output terminal 143b
As a result, one input terminal becomes "H" level, and the gate is in a standby state for closing. When the comparator 115 is inverted at the time when the shutter blade is closed, the other input terminal is also set to "H" level by the non-inverting output terminal 115b. As a result, the gate is closed and the output terminal becomes "L" level. Therefore, the SCR 153 becomes conductive when a positive differential pulse is applied to its gate by the differentiating circuit, and the trigger circuit 155 is driven in synchronization with the maximum opening time of the shutter blade 14 to cause the electroflash to emit light. Also, Nand Gate 149
In addition to using the signal of the output terminal 143b of the comparator 143 as one input signal of the comparator 143 as in this embodiment, the latch circuit 125 as shown in FIG. By providing such a signal, a signal corresponding to the shutter opening timing may be used.

FIG. 22 shows the circuit of FIG.
As shown in the figure, this is a shutter control circuit that incorporates a circuit that prevents erroneous warning display.
The gate input terminal (G) 107f of 07 is controlled by the inverting output terminal 143c of the comparator 143.

Therefore, if self-timer photography is performed under brightness conditions where LED 108 or 109 lights up, the LED 108 or 109 will turn on.
The turning off of the light at 9 also indicates the transition from the end of the self-timer operation to the shutter release.

In addition, Fig. 23 shows a battery check circuit configured using a low brightness warning circuit.
Reference numeral 6,157 denotes a resistor forming a voltage dividing circuit, which schematically shows a circuit that provides a reference voltage for low brightness warning from the output terminal 106b of the reference voltage circuit 106. 158 and 159 are resistors forming a voltage dividing circuit, which detect a voltage drop in the power supply battery 101. 160
and 161 are constant current circuits and constant voltage diodes, which set the check level. 162 is a comparator whose inverting input terminal (-) is connected to resistors 158 and 1.
59, and the non-inverting input terminal (+) is connected to the constant current circuit 160 and the constant voltage diode 1.
It is connected to the connection point with 61. 163 is a transistor whose base is connected to the output terminal of the comparator 162, and whose collector and emitter are connected to the resistor 15.
7 are connected in parallel. When the voltage of the power supply battery 101 is higher than the check level, the comparator 1
Since the potential of the inverting input terminal (-) of the transistor 62 is higher, the output terminal is at the "L" level and the transistor 163 is cut off. Therefore, the battery check circuit portion is rendered irrelevant to the low brightness warning circuit. On the other hand, the power supply battery 101
When the voltage becomes lower than the check level, the output of the comparator 162 goes to the "H" level and turns the transistor 163 on. As a result,
The non-inverting input terminal (+) of the window comparator 107 becomes the potential of the (-) pole of the power supply battery 101, and the output terminal 107e becomes "H" level.
The LED 109 can no longer be lit. Therefore, with the power switch 102 closed, the light receiving element 1
03, if the LED 109 is lit, it means that the voltage of the power battery 101 is above the check level, and if it is not lit, it is displayed that the voltage is below the check level.

Next, a self-timer mechanism in which the self-timer mechanism is reset after one warning operation will be described with reference to FIGS. 14 and 15. The shutter plate 1 is further provided with a pin 1k, and the timer lever 25 is further provided with a protrusion 25c. 27
is a timer set lever pivotally connected to the shaft 28,
A pin 27a for opening and closing the switch 141 and a set pin 27b are installed to form a long groove 27c. Reference numeral 29 designates a timer reset lever pivotally connected to the shaft 30, which is fitted with a long groove 27c and has a pin 29a planted therein that can push the protrusion 25c, and which engages with the back of the bend 15d of the iron piece lever 15. arm to get 2
A spring 31, which is stronger than the spring 26 (not shown), provides dextrorotation until the arm 29b comes into contact with the pin 1k. FIG. 14 shows the self-timer set state. In order to end the self-timer operation, the iron piece 17 is attracted to the electromagnet 117 and the iron piece lever 15 is turned to the right.
Since the back part of the bend 15d is removed from the arm 29b, the reset lever 29 is rotated to the right by the tension of the spring 31, and the pin 29a causes the set lever 27 to be rotated to the left, and the protrusion 25c is pushed to move the timer lever 25 towards the spring 26. Rotate to the right against tension (not shown). As a result, the state shown in Figure 15 is reached,
The pin 27a is retracted and the switch 141 is closed, and the bent 25a of the timer lever 25 is held at a position retracted from the movement trajectory of the hook 4h of the closing drive plate 4.

The self-timer mechanism is set by rotating the set lever 27 to the right from the state shown in FIG. 15 by operating the pin 27b by a set member (not shown). That is, the reset lever 29 releases the spring 31 by turning the set lever 27 to the right.
When the arm 29b is rotated to the left against the tension of the arm 29b, the back of the arm 29b engages the side surface of the bend 15d, and the arm 29b overcomes the bend 15d while rotating the lever 15 to the left, the arm 29b is in the state shown in FIG. The setup is complete. By incorporating this reset mechanism, when the iron piece lever 15 is attracted to the electromagnet 117, the load for turning the timer lever 25 to the right is reduced, so that the attraction operation becomes more reliable.

Furthermore, in this embodiment, exposure time control and self-timer control are performed using one electromagnet.
Separate electromagnets may also be used.

Next, according to FIGS. 16 and 17, the power supply battery 101
The release lock mechanism when the voltage becomes or remains below the specified value will be explained. The shutter plate 1 also has a bent 1l as a stopper.
is formed, and the release lever 2 is further bent 2e.
is formed. Reference numeral 32 denotes a release lock lever pivotally connected to a shaft 33, and an arm 32a that can come into contact with the bending 1l and can face within the movement trajectory of the bending 2e.
and a bend 32b related to the electromagnet 117, the base 32b' of the bend 32b engages one end of the yoke 117b of the electromagnet 117, and the vertical bend 32
b'' faces the side surface of the iron core 117a, and a weak spring 34 provides dextrorotation.

Next, the operation of this embodiment will be explained. As described above, when the release lever 2 is depressed, the power switch 102 is closed and voltage is supplied to each part of the circuit. Since the switch 114 is closed in the initial state, the electromagnet 117 is connected to the resistor 13 as shown in FIG.
A current flows through 7 and is excited. At this time, the magnetic flux generated in the electromagnet 117 is small because the magnetomotive force is weak, and therefore does not reach the point where the iron piece 17 is attracted. On the other hand, the lock lever 32 has a bent portion 32b, an upright bent portion 32b″, and an iron core 1 with respect to the electromagnet 117.
17a, yoke 117b, and base 32b' constitute a magnetic circuit, and when a magnetomotive force that can overcome the weak spring 34 is applied by electromagnet 117, it rotates to the left. Therefore, by verifying whether the current can provide a magnetomotive force above a certain level, it is possible to determine whether or not the power supply battery 101 is usable. The verification level can be set appropriately by adjusting resistor 137. When the voltage of the power supply battery 101 is sufficient and a current equal to or higher than the certification level flows through the electromagnet 117, the lock lever 32 moves to the first position.
As the arm 32a rotates to the left as shown in FIG. 6, the arm 32a retreats from the movement trajectory of the bending 2e, so the release lever 2 can be further depressed. Furthermore, if the current flowing through the electromagnet 117 is below the verification level, the lock lever 32 will bend when the arm 32a is bent as shown in FIG.
1, and the arm 32a bends 2e.
The release lever 2 is prevented from being pressed down by remaining within the movement trajectory of the release lever 2. Furthermore, if a non-magnetic part 117a' is provided in the part of the electromagnet 117 that faces the vertically bent part 32b'' of the iron core 117a,
An air gap is created in the magnetic circuit, and the magnetic flux passing through the magnetic path is reduced, so that the decrease in the magnetic flux that attracts the iron piece 17 later can be suppressed to a small extent.

Note that if the output terminal 107e of the window comparator 107 is also connected to the side of the resistor 137 that is connected to the output terminal 115a of the comparator 115, the release lock can be performed even during a low brightness warning. Further, the lock lever 32 can be pivotally mounted on the release lever 2, and in this case, depending on whether the lock lever 32 is attracted to the electromagnet 117, a part of the lock lever 32 can be attached to a fixing member (not shown). It becomes a state where it is not locked against, or a state where it can be locked. Here, when the lock lever 32 is attracted by the electromagnet 117, the vertical bent portion 32b'' moves to slide on the iron core 117a as the release lever 2 is pressed down, but eventually the non-magnetic portion 117a ′, the same effect as described above can be obtained.Furthermore, the release lock mechanism can be used in cameras with a built-in flash device.
When the power supply for the shutter control circuit is also used to charge the main capacitor of the flash device, the same operation as described above is performed even when the voltage drops during charging.

As described above, according to the present invention, the light-receiving window is opened in advance for the warning operation, and after the light-receiving window is once shielded, the light-receiving diaphragm is also opened in conjunction with the opening of the shutter blades that also serve as aperture blades. In the programmable electric shutter linked to the light-receiving diaphragm, the warning display circuit is latched to a disabled state by an electric signal corresponding to the light intensity attenuation caused by the shielding, so there is no erroneous display at that stage, and it is easy to use. An extremely convenient camera can be provided.

[Brief explanation of the drawing]

Fig. 1 shows the shutter mechanism including the shutter opening control element for flash photography in the set state, Fig. 2 shows the shutter in the open state, and Fig. 3 shows the shutter in the closed state. The diagram shown,
Fig. 4 is a bottom view showing the relationship between the closing drive plate and the leaf spring member, Figs. 5 to 9 are views showing the shutter opening control state during flash photography, and Fig. 10 includes the self-timer control element. Figure 11 shows the shutter mechanism in the set state, Figure 11 shows the self-timer operating, Figure 12 shows the shutter open, and Figure 13 shows the shutter closed. , FIGS. 14 and 15 are diagrams showing the setting and reset relationships of the self-timer mechanism, FIGS. 16 and 17 are diagrams showing the release lock mechanism, and FIGS. 18 to 22 are diagrams showing the shutter control circuit, respectively. FIG. 23 is a circuit diagram showing an example of a battery check circuit. 1... Shutter plate, 1a... Exposure opening, 1b
...light receiving window, 2...release lever, 4...closing drive plate, 4c, 4d...arm, 4h...hook, 6...plate spring member, 7...shutter release lever, 10...opening/closing lever, 12, 12'...conductive ring , 14... Shutter blade, 14d... Shutter opening, 14e... Exposure warning information introduction opening, 14f... Exposure information introduction opening,
15... Iron piece lever, 17... Iron piece, 19... Hold lever, 22... Flash opening lever, 22a...
Cam surface, 25...timer lever, 27...timer set lever, 29...timer reset lever,
32... Release lock lever, 101... Power supply battery, 102... Power switch, 103... Light receiving element,
105... Logarithmic compression diode, 106... Reference voltage circuit, 107... Window comparator, 108,
109...LED, 115, 121, 129, 13
4,143,162...Comparator, 104,1
16,118,148...Amplification circuit, 125...Latch circuit, 117...Electromagnet, "122,123,1
24”, “144,145,146”, “150,1
51, 152''...Capacitors, resistors, and inverters forming the differential circuit, 110, 126, 13
1,139...Capacitor, 113,120,12
7,137,138,142,154,156,
157, 158, 159...Resistance, 119, 132
...variable resistor, 112...logarithmic expansion transistor, 1
28, 133, 135, 163...transistor,
160... Constant current circuit, 161... Constant voltage diode, 111... Changeover switch, 114, 141... Switch.

Claims (1)

[Scope of Claims] 1. The light receiving window is opened in advance for the exposure warning operation, and the light receiving window is once shielded, and the light receiving aperture is also opened in conjunction with the opening of the shutter blade that also serves as the rear aperture blade. In the aperture-linked program electric shutter, a variable voltage output circuit outputs a variable voltage corresponding to the light intensity attenuation due to the shielding, and a fixed reference voltage is compared with the variable voltage of the variable voltage output circuit, and the variable voltage value is determined. a comparator circuit whose output is inverted when the voltage changes from a certain direction and exceeds the reference voltage value; and a memory circuit that stores the inverted state of the output of the comparator circuit and disables the operation of the exposure warning circuit by the stored output. A warning erroneous display prevention circuit characterized by comprising: and.