DE1938826C - Photographic camera with electronic control - Google Patents

Description

The invention relates to a photographic camera with one of the recording brightness influenced photo resistance and an adjustment element for a freely adjustable recording factor, all the factors affecting the recording are stored in a resistance group that simulates them be that with the? The photoresistor is arranged in a balancing bridge circuit, the balancing value of which is entered into an electronic control circuit and the automatically adjustable factor is determined.

It is an object of the present invention, particularly an ^f surface and advantageous arrangement to provide the adjustment device of this type having both a storage of the Einstcllwertes when measuring the recorded image brightness facilitated by the lens, regardless of whether it is a camera with a view finder or Rcflexspiegel . In addition, the arrangement should also be applicable to cameras with interchangeable lenses and allow the factor to be set automatically to be displayed even before the recording is carried out.

These objects are achieved according to the invention in that the adjusting member actuates a contact member, the switching contacts for a servomotor fed from a power source are assigned to the gearbox means on the one hand the adjustment movement of the common holder of the contact member and the Switching contacts and, on the other hand, the setting movement of a carrier for the presettable recording factor associated resistance of the resistance group controls.

In the preferred embodiment of the invention, the adjusting member acts via one in the direction the optical axis displaceable actuating air on the pivotably mounted contact member, wherein the Holder is also arranged displaceably in the direction of this axis.

According to another development of the invention, it is advantageous to provide the holder with a detachable To make coupling can be coupled with a slide that meshes with the gearbox of the servomotor stands so that the holder and the slide by means of a film sensitivity scale in a variable relative position are connectable.

According to a further advantageous embodiment, the grinder is for the presettable take-up factor reproducing resistor attached to a turntable with another grinder, which is made by Another servomotor is driven, which is preferably connected to the balancing bridge via a Amplifier is fed from a power source, the further grinder with another, stationary arranged resistance cooperates, which determines the automatically adjustable recording factor.

A particularly advantageous setting results. if according to another feature of the invention the presettable exposure factor is the aperture value that can be set manually by means of the setting element.

t /

while the automatically adjustable factor is the loading time value of the clasp is.

The description below is an example embodiment the invention on the basis of drawings ^ "explained. It shows

^ge _Fi g. leash camera in top view.

Fi ε ^ the interchangeable unit of this camera in enlarged, partial cross-section,
^g Fig- 3 and 4 shows some details of F i g. 1.

_Fi S 5 the circuit diagram of the Abdeich-Brückcn- ία _of the

and 50 b work with the

men. The elements 44 and 3 "In, ^ ^ _miUe

Holder 46 kept isolated. ^u ^ slot 46 a in

the guide screws 5- una se ' _{b leads} .

Direction d «^ '^" ^ jShn 54 across ver-In the holder ⁴ ^' ^s ^ ^{e! N} , ^ ^U P ^p ' ^U "= ^ α of a slide that can be pushed into one of the boxes _{46 mk dem}

56 intervenes. As a result, J ^ ^'a i _{a Re} tivstellun slider 56 m one of the ^^^ S "are coupled li.chkeitsgen _find', bine ri ν _ski boar

"Bc-

The camera shown as an embodiment has a housing 10 of conventional shape and is with Film transport lever 12 and a rewind 14 equipped. The trigger is labeled 16 the front of the camera is a changeable replaceable attached, in its housing ao

vw _s , hh> P. <: voem with some sectors 20 as well as bend ^ stem with. some "lead lamellas 22 are provided. In addition, in a piece of pipe 18 ad, s firmly connected to the h-Üsc 18,

Member 24 α of the lens by means of a Cicwinde- a _{5 511} Pg 26 is arranged displaceably. The rear usual ^ ed 24 _h seat "firmly to de, Cchäueine back of the screw 61 ^d £ ^u *"^'n S _tromotO re ange62 64 6 of the shaft 64ac "nes Lie. _{Fi" e?} Is exaggerated D · «« Motor is powered by e and can "ink ^" depending on which of the switch contacts so ^^

the contact member 44 8 ^{erade tm} o _ch ?. _{ccke 65} Festge-screw 61 is provided with a further screw w ^ couples the in «« Z ^ah nsegmcm '^ ^ - ^ is the same em W iderstan ^ύ ™ 5 _widcr...

a grinder 68 ™ * ^mm ™ * ™ _n '' ^ i _n Γ ig 5 stood 66 and the grinder «smd ^ er ^ n ^ illustrated way mn unem 1 h

^Se ρ ',!' Aperture blades 22 are of conventional shape. Jcd. Lamella 22 is mounted on a stationary bearing pin Ua and carries a sleuer pin 22 h. which is in a control slot 28 "of a Biendstellers 28 emgU. which, via its arm 28 /, is coupled to an outer linstcllßlicd 30 of annular shape "'each of the sectors 20 is with its l.agerMift"

20, stored in the pipe section 18 ″ and gripped - w.e

_IS 7 shows - with its control slot 20 b one

Control pin 32 "of a sector drive ring 32, the voltage of the ^
Le.lung 78 to one
again with emen1
the batter e 84 " ^tkr
In the main house
^ ahet ^ jeSjromk- '

^ te Jeil-

^ de'r

strengthened «» _{r g2 and}

^fe _{s,. holders 8} 6 "and Sc1, ^ ^^

with unem

together, the ^dc
one electronic

resistance

_{n for} the Belichn ^ _ha , _

they ϊ, τώίΐίΐϊ ^

Came, in connection with Mol ,, and at ,,, De.ü.isen des

I.e .. ». You

,, ^ ₈ eh _a lc “becomes the ^ _5cle , nbci, in d K

The locking lever 38 at the same time also forms the armature of an electromagnet 40. The mode of action of this magnet still explained w.rd. ,, ".

The exchange unit 18, h is fixedly connected to a BajonctplaUe 8, the bayonet projections 18 rin Hajonettlappcn 10 α of Kamcragehauses 10 in a known manner and engage E.nhe.t 18 som.t detachably with the camera 10 connect.

The aperture emstellrine 30 is at its k: .mer:., E .- "gen Front side with a Sieuerkum · 30 «1 aussesiat-, et. The one lying in the direction of the optical axis Control pin 42 with its ν ore end prints. |) The back linden of this pen looks with a contact 44 in the l-in grill. that at 44 "at a stop,

does not occur, are ^^ we.

the lens opening and the misunderstood JJ ^e ' ^St ^ during the proper

release. Such ^ ^ _{yourc must dcm trigger r}

J _ni , _{si; notices} are to s.ch _{ie h} t _{cr for} the sake of clarity

So ^

not D

D- 1 1. ^

_{| 8 imported} lilek _tron1 circle of an electron.schcn _llbilduri! ,, whose switching

; ;, _{ls Stronu!} uelie serving Bat-SC ,,,,. ,": .Nd w*

Transistors 104 and 106. The RC element of this device form the timing resistor 92 and a capacitor 108. With 110 and 112 are Denotes resistors, while a potentiometer 114 is used to adjust the device. The condenser 108 is assigned a further transistor 116, which is made conductive by an induction pulse from a coil 118 and then via the resistor 120 allows the capacitor 108 to discharge. The induction shock is shaped by a capacitor 122, a diode 124 and a resistor.

The coil 118 encloses a metallic transverse pin 128 (FIG. 7), which is connected to the pole pieces 130 a permanent magnet 132 fixed in the lock housing 18 is connected. The sector drive ring 32 has a metallic tab 32 c. which in a certain operating position on the pole pieces 130 rests in the vicinity of the coil 118.

The circuit shown in FIG. 5 is accommodated in the camera housing with the exception of the control device 94. The film sensitivity scale 58 is visible through an opening 10 ft in the camera housing 10 (FIG. 3). the coupling tooth 54 carrying an adjusting knob 54 α , which serves as an index for the scale 58. The trigger (FIG. 4) is under the action of a return spring 134, while a further, stronger spring 136 forms a pressure point for the trigger as soon as it is depressed by the empty amount "X". The main switch for switches 86 a, 86 b is represented by the insulated collar 86 on the trigger 16.

The lines 138, 140 of the control circuit 94 accommodated in the lock housing are as sliding contacts formed, which when attaching the interchangeable unit 18 to the camera 10 with the associated Automatically couple mating contacts on the camera side.

The photoresistor 70 is arranged inside the camera 10 behind the lens in a known and therefore not shown manner, so that an internal measurement of the exposure brightness can take place. The slider 90 is assigned an index α 90, which is visible through an opening 1or in the camera 10 and cooperates with a Belichiungszeiiskala "42" τη camera body.

The adjustment arrangement described works in the following way: Before the recording, the operator has to cock the shutter and use the coupling teeth 54, 54 a and the associated scale 58 to establish the relative position between the holder 46 and the slide 56 and thus set the given film value. He also has to set the diaphragm divider 30 to the desired diaphragm value, for which purpose a diaphragm scale 30 6 on the circumference of the ring 30 and a fixed index 31 are used. When turning the diaphragm plate 30, its curve 30a will move the pin 42 axially, for example to the rear (according to FIGS. 1 and 5 downwards). As a result, the contact member 44 is pressed from its central rest position, in which it does not engage with any of the switching contacts 50 a, 50 £>, against the contact 50 a.

If the trigger 16 is now depressed via the Leenveg "X" as far as the palpable pressure point on the spring 136, the switches 86 α, 86 & are closed by the main switch 86. Since the interchangeable unit 18 is seated on the camera, the safety switch 98 is also closed, so that when contact is made with 44/50 ″, the motor 64 begins to run, for example, in clockwise direction. The slide 56 and the holder 46 are adjusted downward via the gear means 61, 62 in the direction of arrow A , until the adjusting spring 48 brings the contact member 44 back into its rest position or middle position, in which it again does not work with any the contacts 50 a, 50 b has contacts. The motor 64 and the parts 46, 56 then stop.

ίο When the motor 64 is running, the worm 65 also rotates the toothed segment 63, so that the opposing land 66 carried by it is in a relative position his grinder 68, which is set by hand via the diaphragm plate 30 Blendenwerl (»5.6« as shown).

When the switch 86 b is closed, the motor 82 is fed from the battery R4 via the amplifier 80, so that it begins to run in a certain direction. The turntable 88 is with the

ao grinders 68 and 90 rotated, so that now the from Grinder 63 attacked the value of the resistor 66 with the value of the respective exposure brightness detecting photoresistor 70 is balanced in the bridge circuit. Once the match is achieved is, d. i.e., the resistances in the bridge circuit are balanced, the current is supplied to the motor 82 interrupted again, so that he stops. The grinder 90 on the now also stationary turntable 88 determines a memory resistance value at resistor 92, which together with the Factors "aperture value", "film speed value" and "brightness value" in the control circuit 94 an exposure-appropriate measurement of the automatically adjustable value "exposure time" of the shutter results.

As long as he holds the trigger 16 at the pressure point of the spring 136, the operator can read this measured and stored exposure time value on the scale 142 by means of the index 90 α. If the displayed exposure time value does not appear to him to be suitable for the exposure, he can set a different aperture value via the diaphragm plate 30, which results in a new storage value for the exposure time at the resistor 92 in the manner already described.

When a suitable exposure time value is then displayed, the operator only has to press the shutter release further down over the pressure point until its lower end 16 α reaches the locking lever 36 (FIG. 7) and swivels it counterclockwise. The switch 102 assigned to the locking lever 36 is closed and the battery 100 is connected to the circuit. At this point in time, the capacitor 108 still has a residual charge from the previous exposure, the size of which is not constant due to various influences, but is always below the base of the emitter voltage of the first transistor 104. Since a voltage drop occurs at the common emitter resistor 114 when the battery 100 is switched on, which increases the emitter of the transistor 104, the voltage of this transistor definitely does not reach its breakdown height at this point in time. The transistor 104 blocks, while the transistor 106 is conductive and the electromagnet 40 is energized. He now holds his anchor 38, which was pressed against him during the clamping movement, in the position according to FIG. 7 fixed.
After actuating the locking lever 36, sicri moves

also the arm 32 e away from the permanent magnet 130/132, as a result of which a brief induction surge occurs in the coil 118. This is given as a pulse to the transistor 116 , which thereby briefly becomes conductive and enables the capacitor 108 to be discharged from the residual voltage to zero voltage. After this discharge, a new charging of the capacitor 108 from the battery 100 begins immediately.

The sector drive ring 32 triggered at 32 b moves from the clamping position according to FIG. 7 counterclockwise into a position in which its projection 32 c rests on the fixed armature 38. The sector drive ring 32 is thus stopped in the open position of the sectors 20. The sectors remain open as long as the magnet 40 remains energized.

If now, after the time span measured by the time-determining resistor 92, the capacitor 108 exceeds the breakdown voltage of the trigger

gers reached, it tips over. The transistor 104 becomes conductive while the transistor 106 blocks. The armature 38 drops from the currentless electromagnet 40 and the sector drive ring 32 can now move

S continue to move counterclockwise to its rest position, the sectors 20 closing again. This ends the exposure process.

It should also be mentioned that the setting arrangement according to the invention with storage and preview

ίο the recording factor value to be set automatically can also be used in a camera other than the one shown. You can, for example, with one-eyed Single-lens reflex cameras with or without interchangeable lenses are used accordingly. Besides that one could also enter the exposure time value by means of a manual control and that is after adjustment Use the resistance value resulting from the bridge for the automatic setting of the aperture value.

1 sheet of drawings

Claims (8)

Patent claims: 1. Photographic camera with a photoresistor that can be influenced by the exposure brightness and an adjustment element for a freely presettable exposure factor, with all factors acting on the exposure being stored in a resistor group that simulates them and is arranged with the photoresistor in an adjustment bridge circuit, the adjustment value in an electronic control circuit is entered and the automatically adjustable factor is determined, characterized in that the setting member (30) actuates a contact member (44) to the switching contacts (50 a, SO b) for a servomotor (64) fed from a power source (67) are assigned, which via gear means (61, 62, 65) on the one hand the setting movement per common holder (46), the con tact member and the switching contacts and on the other hand the setting movement of a carrier (63) for the resistance (66) assigned to the presettable absorption factor Resistance group controls. 2. Photographic camera according to claim 1, characterized in that the adjusting member via an adjusting pin (42) that can be moved in the direction of the optical axis onto the pivotably mounted Contact member (44) acts, the holder (46) also being displaceable in the direction of this axis is arranged. 3. Photographic camera according to claim 2, characterized in that the holder (46) over a releasable coupling (54) can be coupled to a slide (56) which centers with the gears (61, 62, 65) of the servomotor (64) is in engagement, so that the holder and the slide by means of a Film sensitivity scale (58) can be coupled in a variable relative position. 4. Photographic camera according to claim 1, characterized in that the grinder (68) for the resistance (66) reproducing the presettable recording factor with a further one Grinder (90) are arranged on a turntable (88), which is driven by a further servomotor (82) is driven, which is preferably connected to the balancing bridge via a Amplifier (80) is fed from a current source (84). 5. Photographic camera according to claim 4, characterized in that the further grinder (90) interacts with a further, fixedly arranged resistor (92), which automatically adjustable intake factor determined. 6. Photographic camera according to one of the preceding claims, characterized in that that the presettable take-up factor can be set manually by means of the setting member (30) The aperture value, while the automatically adjustable factor, is the exposure time value of the shutter is. 7. Photographic camera according to one of the preceding claims, characterized in that the stored resistance value for the recording factor to be set automatically is displayed by means of a scale (142). 8. A photographic camera according to claim 4 and 7, characterized in that the further grinder (90) carries an index (90 a) which cooperates with a fixed exposure time scale (142) .