JPS584329B2 - display device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a display circuit for displaying a state in which a flash device is ready to emit light.

Conventionally, as a light emission ready display device for a flash device, the charging voltage of a main capacitor is detected by a neon tube connected in parallel to the main capacitor, and when the charging voltage of the capacitor is charged to a potential that enables light emission, a neon light is emitted. Devices for lighting tubes are known.

As mentioned above, the conventional display device applies the charging voltage of the main capacitor to the neon tube connected in parallel to the main capacitor, and indicates the charging completion state by lighting the neon tube, so it can be used as a display element. This was inconvenient because display elements such as small lamps and light emitting diodes could not be used.

In other words, display elements such as small lamps and light-emitting diodes are driven at low voltages and large currents flow when they are driven, so if these display elements are used in place of neon tubes in conventional display devices, large currents will flow during display. The drawback is that the charging current of the main capacitor may be affected.

For this reason, in conventional display devices, it is necessary to use a neon tube as the display element indicating that the light emission is ready, and even when the light emission ready state is to be shown in the viewfinder of a camera, a neon tube is used as the display element. It was inconvenient.

In order to solve this problem, it is possible to use the power supply on the camera side to turn on the display element so that a small lamp or light emitting diode can be used as the display element, but the capacity of the power supply on the camera side may be has an extremely small capacity, and since the light emission ready status is displayed immediately after the main capacitor is fully charged, the light is displayed for a relatively long time, which is inconvenient in terms of power consumption on the camera side.

The present invention has been made in view of this point, and includes a detection means for detecting the charging current of the main capacitor and a switching means for switching based on the output of the detection means. The present invention provides a display device that enables the use of a display element driven by a low voltage and large current, such as a small lamp or a light emitting diode, as a display element that is ready to emit light by applying a voltage from the display element through the switching means. be.

In other words, the present invention drives the display element with the voltage on the primary side of the power supply circuit of the flash device, thereby having no effect on the secondary side output of the power supply circuit of the flash device that supplies the charging current to the main capacitor. It is an object of the present invention to provide a display device in which a light emission preparation completion display can be performed without any problems, and a display element such as a small lamp or a light emitting diode can be used as a display element.

Next, a display device according to the present invention will be explained.

FIG. 1 is a mechanical diagram showing one embodiment of an aperture control mechanism used in a camera system to which a display device according to the present invention is applied.

In the figure, reference numeral 1 denotes an aperture setting ring, which is used by aligning the scale of a desired aperture with the fixed index M1.

Reference numeral 1a denotes a convex portion of the aperture setting ring 1, which is displaced as 1a'' when set to the maximum aperture and 1a'' when set to the minimum aperture.

1b is a concave and convex portion for holding a click, and 1c is a fixedly supported click spring.

Reference numeral 2 denotes an aperture ring which is constantly biased to rotate clockwise by a pin 2a and a spring 2b installed therein.

2 further includes an insulating pin 2c and a rotating shaft 2d of the three-pronged lever 3.
, pin 2e, lock claw 4, and lever 5 rotation shaft 2f,
Values are set for pins 2g, 2h, etc.

The three-pronged lever 3 has a pin 3a, vertical bent portions 3b and 3C, and is given a counterclockwise rotational habit by a spring 3d and pin 2e.

At the tip of the lock claw 4, there is a claw portion 4a that engages with the lever 3C, and the other leg 4b, and the spring 4C and the pin 5a of the lever 5 pull the claws 4 and 5 together.

The lever 5 is given the habit of rotating clockwise by a spring 5b, and the foot 5c is in contact with the bottle 2g.

An iron piece 6 is attached to 5 with a degree of rotational freedom via a pin 5d of 5, and this iron piece 6 is normally in contact with a magnet Mg mounted on a fixed support.

7 is a fixing pin for returning the three-pronged lever 3 to its original position.

Reference numeral 8 denotes an intermediate lever which is given the habit of rotating clockwise around a shaft 8a by a spring 8b.The force leg 8C is the pin 2a, and the other force leg 8d is the fixing pin 9 and the release lever.
10 pins 10a.

A pin 10b is further planted in the release lever 10, and is pulled upward by a spring 10c. Ru.

10d is an insulated pin. S and S2 are insulation bins 10d
and 2c are switches that are opened and closed.

Reference numeral 11 adjusts the scale to the fixed index M2 according to the guide number of the flash device used in the guide number setting ring.

CAT is the setting position when using a special flash device for this device, and the guide number scale is as described above (AS
The guide number at A=100 should be set.

11 has cam portions 11a and 11l] and a click hole 11C for holding 11 in a desired position by a click leaf spring.

The stop lever 13 has a vertical part 13a and a cam part 13t)
There is a fixed pin 13e centered around the fixed rotating shaft 13d.
A clockwise rotational behavior is provided by the spring 13C.

The lever 14 has a pin 14a and a rotating shaft 15 of the lever 15.
b, and is given the habit of rotating counterclockwise around a fixed co-rotating shaft 14C by a spring 14d and a fixed pin 14e.

The lever 15 is rotatably supported by the lever 14, and the lever 15 is rotatably supported by the lever 14.
5a is a spring 14d attached to the distance cam 17 (interlocked with the distance ring)
are pressed together by the force of

On the other side is the rotation shaft 15b of the lever 16.

A pin 16a of the lever 16 rotatably supported by the lever 15 is pressed against the ASA cam 18, and the other pin 16b is pressed against the cam portion 11a or 11b of the lever 11 by the force of a spring 14d.

FIG. 2 is a circuit diagram showing an embodiment of a camera system to which a display device according to the present invention is applied.

In the figure, S1 is the switch explained in FIG. 1.

S2 is a switch that is turned off when the engagement between the clock pawl 4 and the three-pronged lever 3 shown in FIG. It is turned on when the photographer operates the operating member in conjunction with the member.

S4 is a count start switch that is turned off when the shutter blade is opened in conjunction with a shutter blade (not shown).

S5 is a switch that opens and closes in conjunction with an external operating member (not shown), and when a device other than a dedicated flash device is used, the operating member is operated to close the switch.

S6 and S7 are power switches for the flash device which are interlocked with each other, and both are turned on by operating a power button (not shown) provided on the flash device.

C1 is a counting capacitor of an electronic shutter circuit that constitutes a timer circuit connected to the light receiving element P, and when the switch S4 is turned off in conjunction with the opening of the shutter blade, the charging operation of C1 is started. .

20 is a Schmitt trigger circuit that detects the charging voltage of the capacitor C1 and switches when the charging potential of the capacitor reaches a predetermined level; M is a shutter blade closing magnet connected to the output end of the Schmitt trigger circuit; By switching the trigger circuit, the magnet is de-energized, and the shutter blades interlocked with the magnet are driven to close the shutter.

The light receiving element P1 capacitor C1, Schmitt trigger circuit 20, magnet M, count start switch S
4 constitutes an electronic shutter circuit.

Note that 19 is a diaphragm plate provided in front of the light receiving element P, and the aperture of the diaphragm plate is determined in conjunction with the diaphragm mechanism shown in FIG.

21 is a booster circuit consisting of a DC/DC converter etc. that boosts the output of the power supply E2 applied to the negative side, D is a diode that rectifies the secondary output of the booster circuit, and C2 is charged by the output of the booster circuit. The personal main capacitor R2 and R3 are voltage dividing resistors connected in parallel with the capacitor C2, and the resistor is the main capacitor C2.
Outputs the partial voltage of the charging voltage.

L2 is a neon tube connected to the output end of the voltage dividing resistor,
In the neon tube L2, the output of the voltage dividing resistor is at a predetermined level, that is,
It turns on when the main capacitor is charged to a voltage sufficient to guarantee flash emission.

These resistors R2 and R3 and the neon tube L2 constitute a charging completion detection circuit, and when the charging potential of the main capacitor reaches a predetermined level or higher, the neon tube L2 is turned on and a detection output is generated.

Q is a transistor as a semiconductor switching means for driving a display means which will be described later, one main electrode (collector) of which is connected to one electrode of the power supply, and the other main electrode (emitter) connected to the first external terminal 26 and the first external terminal 26. It is connected to a lamp L3 as a display means via one connection terminal 29.

The control electrode (base) of the transistor is connected to the neon tube L2, and the transistor Q is turned on in response to a detection output generated by turning on the neon tube L2.

Mg is the magnet explained in FIG.
g, the lamps ■, 3 and the switches S1, S2
are connected in series.

The series body of the magnet Mg1 lamp L3 and the switches S1 and S2 is connected between the first connection terminal 29 and the second connection terminal 31.

By attaching the flash device to the accessory shoe 22 of the camera, the first connection terminal 29 is connected to the first external terminal 26, and the second connection terminal 31 is connected to the second external terminal 24.

According to the configuration described in L, the flash device is attached to the camera, the power of the flash device is turned on, and when the main capacitor is fully charged, a display hand is displayed to indicate the completion of charging. Lamp L3 as
is transistor Q-terminal 26.29-switch S1,
S, - Magnet Mg one terminal 24.31 - Switch S6
, S7 is connected to the power source E2.

L1 is a flash discharge tube, C3 is an L-rigger capacitor charged by the output of the booster circuit 21, and T1 and T2 are primary and secondary coils constituting a trigger transformer.

X is a synchro contact that is linked to the shutter blade and turns on when the shutter opens.

When the contact X is turned on, the capacitor C3, coil T switch S7, terminals 24, 31, contact X1 terminal 2
7 and 23, the charge in the capacitor C3 is discharged to the trigger coil T1, a trigger pulse is generated in the coil T2, and the flash discharge tube L1 is triggered.

22 is a camera accessory shoe for attaching a flash device, and 29 is a first connection terminal in a part of the shoe;
31 is a second connection terminal, 28 is a third connection terminal, 27 is a fourth connection terminal, and 30 is an insulating member.

Also, 26, 24, 25.23 are the external terminals of the flash device.
is the first external terminal, 24 is the second external terminal, and 25 is the third external terminal.
23 indicates a fourth connection terminal.

By attaching the flash device to a portion of the camera shoe, each terminal is connected as shown.

Note that R4 is a variable resistor for adjustment.

Next, the operation of the camera system to which the apparatus according to the present invention shown in FIGS. 1 and 2 is applied will be explained.

Operate the camera's operating member to turn on switch S3, S5
What if I attach the flash device to the accessory shoe 22 of the camera with the flash device turned off, operate the power button on the flash device, and close switches S and S7? The voltage of the power source E2 is boosted by the booster circuit 21, and the output of the booster circuit 21 charges the main capacitor C and the trigger capacitor 03.

2 When C2 is sufficiently charged, the neon tube L2 is turned on and the transistor Q shifts to the normal state.

When the release lever 10 shown in FIG. 1 is pressed down, the switch S is first closed.

Also, in the initial state, switch S2 is turned on as described above, so when switch S1 is closed, transistor Q, terminals 26 and 27, switches S and S2, terminals 31 and 24, switch S7, Magnet Mg and lamp L3 via S6
Sufficient current is supplied from the electromagnetic force E2, the Mg attracts the iron piece 6 shown in FIG. 1, and the lamp L3 lights up to warn that flash photography is possible.

When the release lever is further depressed, since Mg is on, the aperture switching control device is automatically switched to flash photography, and the aperture diameter is adjusted to an appropriate value according to the distance, etc.

That is, if the lever 10 is further pressed after closing the switch S1 by pressing the release lever 10, the intermediate release lever 8
The leg 8d is pressed down by the pin 10b, and the other leg 8c moves upwards, and the aperture ring 2 begins to rotate clockwise while pressing against the pin 2a.At this time, as described above, the flash photography Since the preparation is complete and Mg is on, the iron piece 6 is attracted, and the rotating shaft 2f of the lever 5 applies a counterclockwise rotational force to the lock claw 4, which moves to the right through the pin 5a. give.

As a result, the engagement between 4a and 3C is broken, and as the aperture ring 2 rotates, the relationship between the fixing pin 7 and the three-pronged lever 3 is severed, and the pin 2e stops 3 in the state shown by the dotted line in the figure. .

As soon as the engagement between 4a and 30 is broken, switch S2 connected in series to Mg is turned off, and Mg is turned off.

As the release lever continues to be pressed down, the three-pronged lever 3 will eventually be released.
The pin 3a hits the bent portion 13a of the stop lever 13, which is positioned as a result by the pin 14a of the lever 14, which is positioned by the GNO, ASA distance, etc.

As a result, the amount of rotation of the aperture ring 2 is determined based on the distance and other information, and the aperture diameter is adjusted to be suitable for flash photography.

After the aperture is determined in this way, pressing down on the release lever further releases the shutter and opens the shutter blades.

When the synchro contact X closes in synchronization with this, the capacitor C3 of the trigger circuit becomes
7, 23, etc., a high voltage is generated at T2, and the discharge tube L1 emits a flash of light.

The light-receiving element P of the electronic shutter circuit is inputted with information about the subject brightness and the ASA and aperture value from the aperture plate 19, and is activated by the switch S4 in synchronization with the release of the shutter.
When the capacitor C1 is opened, the capacitor C1 begins to be charged by the power source E1, and after a predetermined period of time, the trigger level of the Schmitt trigger circuit 20 is reached, the magnet M is activated, and the shutter is closed.

At this time, the circuit of the flash device is also connected to the capacitor C1, and when the neon tube L2 is turned on, not only is a charging current supplied to the capacitor C1 via the light receiving element P. , resistor R4, and terminals 25 and 28.

Therefore, even if the subject is completely dark and the resistance value of the light-receiving element P is almost infinite, the resistance value of the resistor R4 can be adjusted so that the magnet M is activated in 1/30 seconds, for example. By setting the shutter speed to 1/30 seconds, the shutter speed is adjusted to 1/30 seconds during flash photography at night.

As described above, in the display device according to the present invention, one drive power to the display element that displays the completion of charging, that is, the completion of light emission is supplied by the primary output regardless of the secondary output of the power supply circuit of the flash device. Since it is configured to do so, it is possible to use a small lamp or a light emitting diode as a display element, and it has many effects such as becoming an extremely suitable display device when displaying the ready state of light emission in the viewfinder. It is something to play.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram showing an embodiment of an aperture control mechanism constituting a camera system to which a display device according to the present invention is applied, and FIG. 2 is a configuration diagram showing an embodiment of a camera system to which a display device according to the present invention is applied. FIG. E2... Power supply, 21... Boost circuit, C
2... Main capacitor, R2, R3...
...Resistance, L2...Neon tube, Q...
・Transistor, L3...Display element.

Claims (1)

[Claims] 1. A booster circuit that boosts the power supply battery and supplies power to the main capacitor; a detection circuit that detects the charging voltage of the main capacitor and generates a detection output when the charging voltage of the main capacitor reaches a predetermined value; A collector and an emitter are connected between an external terminal, a second external terminal connected to one electrode side of the power battery, and the other electrode side of the power battery and the first external terminal, and a flash device including a transistor whose base is connected to the output side of the detection circuit and switches in response to the detection output; a first connection terminal that connects to the first external terminal when the flash device is attached; a camera comprising: a second connection terminal connected to the second external terminal; and a display means connected between the first connection terminal and the second connection terminal; A display device characterized in that a closed circuit is formed between the power source battery and the display means, one drive power for the display means is supplied by the closed circuit, and the display means is driven only by the output of the power source battery.