DE2827987A1 - CAMERA WITH BUILT-IN ELECTRICAL FLASH - Google Patents

Description

Applicant: Balda-Werke Photographic equipment and plastic GmbH & Co. KG, Steinmeisterstr. 16, 4980 frets 1

"Camera with built-in, electric flash unit"

The invention relates to a camera with a built-in electrical Flash unit and shutter release.

In known cameras of this type, the two are different Parts, namely camera on the one hand and flash device on the other hand, are only combined in a common housing. The flash units used have a manually operated on and off switch. With such hand-operated flash units takes place - even if they are inserted in a camera housing, a new charge immediately after the flash, even if when no new flash is needed after the last flash. This leads to an unnecessary loss of energy even if that The device is switched off while the new charging process is in progress.

Another significant disadvantage of the known devices is that you can forget the flash device under certain circumstances switch off and put away the flash unit that has not been switched off. This leads to a safe discharge of the batteries of the Flash unit. This is particularly disadvantageous when it comes to rechargeable batteries Batteries, since they are destroyed in most cases by a complete discharge.

909883/0091

11 581 - / - June 23, 1978

Based on this prior art, the invention is based on the object of providing a camera of the type mentioned at the beginning create, in which the operation effort for the flash unit and the camera is greatly reduced and the activation of the flash unit depending on the existing light conditions is possible by means of the shutter release button. Included the flash unit should switch off automatically after reaching the specified amount of charge on its high-voltage capacitor v / earth. The shutter release should either operate the shutter or switch on the charging current for the flash unit.

To solve this problem, it is proposed according to the invention that that the shutter release is in engagement with movably mounted intermediate members, which have an electromagnet and an associated magnet armature, wherein the magnet armature rests against the electromagnet in its first position and has fallen away from it in its second position, and that when the shutter release, which advances the intermediate links, is actuated, in the first position of the armature the flash is charged and when the shutter release is pressed in the second Position of the armature the lock is triggered.

In a further embodiment of the invention, the The position of the armature can be changed depending on the amount of light available at the location.

It has also proven to be useful that the electromagnet and the magnet armature until a predetermined amount of charge is reached can be locked in the switched-on position for the charging current of the flash unit and then by dropping the magnet armature be moved from the locking position by a return spring.

Finally, it is proposed according to the invention that the The magnet armature always falls away from the electromagnet when a given amount of charge is present.

909883/0091

11 581 "Ζ" June 23, 1978

The following is a preferred embodiment of the invention described in detail with reference to the drawing. Show it:

Figure 1 is a section through the mechanical part of a shutter release device, which also the triggering device for the built-in flash unit is, with a first position of the Release button,

FIG. 2 shows the representation according to FIG. 1 in the state after the shutter has been released when the shutter is depressed Release button,

Figure 3 shows the representation according to Figures 1 and 2 at

further depressed release button, with a shutter release despite the depression has not occurred and the flash is charging,

Figure 4 is a circuit diagram of the electrical components.

When the trigger 30 is pressed down slightly from the position shown in FIG. 1, the return pin 30a gives the Slats of the spring switches S1 and S4 free, so that these two Switches are closed at the same time. The meaning of the switch S4 will be explained later.

A voltage divider is formed by the photoelectric element 1 and the resistor 2, which the threshold value circuit 3, for example switches a Schmitt trigger.

It will first be described the case in which a sufficient amount of light is available, so that a flash of the built-in Flash unit is unnecessary. In this case, the photoelectric element 1 has a comparatively low resistance and the threshold switch S3 consequently does not switch through. The indicator lamp 4 does not light up and the electromagnet> '1 remains de-energized. When the shutter release is pressed down further, the lower side of the shutter rests on the upper side of the pivotably mounted magnet carrier 28. When pivoting

909883/009 1

INSPECTED

fi 581 - / - June 23, 1978

of the magnet carrier 28, the magnet armature 27 or its nose 27a is released from the stop pin 29. Under the force of the return spring 25 for the armature 27, the latter is pivoted with its lower end to the right. He comes with a shoulder 27b to rest on a nose 3 3a of a release pawl 33, which is in engagement with a pretensioned Shutter tension lever 34 of a shutter. If the trigger is depressed further, the release pawl 33 pivoted to the left and the nose 33b releases the locking lever 3 4 so that it is in the position shown in FIG can snap.

If there is insufficient light, the shutter will not be released and the shutter tensioning lever will not be actuated 34 before the built-in flash unit is not sufficiently charged.

If the lighting conditions are insufficient, the resistance of the photoelectric element 1 is comparatively high. this leads to a switching through of the threshold value circuit 3 and to the fact that the indicator lamp 4 lights up and the magnet M 1 is energized. The energization of the magnet M 1 ensures that when you press the trigger and when pivoting the Magnet carrier 28 of the armature 2 7 is always held in contact with the magnet M 1. When the The device assumes the position shown in FIG. 3 with the release button 30 in the lowest position. The magnet anchor 27 reaches behind the spring-loaded retaining pawl 31 and closes at the same time the adjacent switches S 2 and S 3, of which only the front one is visible in FIGS. 1 to 3. Closing switches S 2 and S 3 has the following effects:

The switch S 3 switches to the passage of current to the magnet M1. Its energization has the consequence that the magnet M 1 continues to hold the armature 27 even when the light conditions, which lead to a change in the resistance of the photoelectric element 1, change.

909883/009 1

ORIGINAL INSPECTED

^{11 581} - ^ - 23.6.1978

The switch S 2 initiates the charging process for the flash unit. The flash unit consists of a high voltage transformer 7, the resistor 8, an ignition capacitor 10, an ignition transformer 11, a flash tube 12, the ignition electrode 13 and the charging capacitor 14. The synchronous contacts 15 and 16 lead to the shutter of the camera.

Reference numerals 17 to 23 designate resistors of a device which will be described in more detail below.

The resistors 17, 18, 19 and 20 form a variable voltage divider in that the resistor 20 is bridged by means of a transistor T 3 in one switching state and is switched on in the other switching state. During the charging time of the flash unit, the resistor 20 is bridged. As soon as a predetermined voltage is reached on the charging capacitor 14, the glow lamp 24 lights up and thus signals that the lightning bolt is ready. The transistor T 3 is conductive in this state and applies a negative potential to the transistor T 1, which thereby becomes conductive. This makes the magnet M ₉ conductive and the base of the transistor T 2 becomes positive. The transistor T 2 therefore blocks and the magnet M 1 is de-energized. The spring 26 can therefore move the armature 27 out of the contact position forwards according to FIG. 2 and, under the action of the return spring 25, the retrieved magnet carrier 28 presses the trigger 30 back into its starting position according to FIG. 1. When the magnet armature 27 goes up, it is pushed out of its inclined position by the stop pin 29 back into its contact position according to FIG.

Shortly before reaching the upper end position of the trigger 30, its return pin 30a opens the two at the same time Switches S 1 and S 4. Opening the switch S 4 causes the charging capacitor 14 of the flash unit to last longer the flashing retains sufficient voltage as if a switch S 4 were not available and the discharge of the charging capacitor

90988 3/0091 ~ ° ~

11 581 - γ- 23.6.W ₈

sators 14 on the switched-on electronic components could be done. The switch S 4 turns off the otherwise existing consumers and in this way is a longer flash readiness achieved. The flash readiness is signaled on the one hand by the glow lamp 24, on the other hand by the release button 30 jumping out. It consists So there is an acoustic or mechanical as well as an optical control for the flash readiness.

If the release button is now depressed again after charging the charging capacitor 14, first the two switches S 1 and S 4 are closed again. This has the consequence that the transistor T4 turns on. Through this the transistor T 1 becomes conductive and this in turn blocks the transistor T 2. By blocking the transistor T 2 the magnet M 1 is de-energized and the lamp 4 does not light up. The magnet M ~, which now attracts, switches the diaphragm of the Camera in the correct position for flash photography.

Since the magnet M1 is de-energized, the armature 27 can be pivoted into the position shown in FIG the triggering take place in the same way as dicrs was described at the beginning in connection with the actuation of the shutter without flash. When the shutter is released the synchro contacts 15 and 16 are bridged in a known manner and this causes the flash unit to flash.

Unless the flash is flashed immediately after the flash unit has been charged, the flash readiness remains for a certain period of time. By opening the switch S.-2 the transistor is T 3 blocked. The resistor 20 is actively included in the voltage division. Switching off the glow lamp 2 4 takes place at a much lower voltage than was necessary for switching on the glow lamp. The device described thus forms an artificial hysteresis.

909883/009 1

L e r s e i t e

Claims (4)

Patent claims: '1. Camera with built-in electric flash device and shutter release, characterized in that the shutter release (30) engages with movable intermediate members (28, M *, 27) which have an electromagnet (Mj) and an associated magnet armature (27), with the armature (27) rests in its first position on the electromagnet (M-]) and has fallen off in its second position, and that when the shutter release (30), which _{moves the intermediate members (28, M 1} ; 27), is actuated, in the first position of the armature (27) charges the flash unit and when the shutter release (30) is actuated in the second position of the armature (27) the shutter is released. 2. Camera according to claim 1, characterized ο t that the position of the magnotanker (27) is dependent on can be changed by the amount of light present at the recording location. 3. Camera according to claims 1 and / or 2, characterized in that the electromagnet (M-]) and the Magnetic armature (27) in the switch-on position for the charging current of the flash unit until a specified amount of charge is reached can be locked and then moved out of the locking position by a return spring (25) falling off the magnet armature (27) will. 4. Camera according to one or more of claims 1 to 3, d adurch characterized in that the magnet armature (27) 909883/0091 ORIGINAL INSPECTED 581-2 - June 23, 1978 if there is a given amount of charge, always from the Electromagnet (M-]) falls off. 909883/009 1