DE657271C - Photographic camera with interchangeable lenses and viewfinder - Google Patents

Description

GERMAN EMPIRE

ISSUED ON
FEBRUARY 28, 1938

REICHSPÄTENTAMT

PATENT LETTERING

CLASS 57a GROUP 9oi

Kodak Akt.-Ges. in Berlin*)

Patented in the German Empire on November 28, 1935

The invention relates to photographic cameras with interchangeable lenses of different focal lengths and one. Viewfinder with adjustable image field limitation.
In the previously known arrangements of this type, the viewfinder image detail could be adapted to the image detail of the various interchangeable camera lenses, but the switchover could be done

ίο the viewfinder field limit when replacing of the lens are forgotten, so that the recorded image did not correspond to the one that the viewfinder showed when taking the picture.

According to the invention, the holding device of the lens on the camera is inevitably in Depending on the mask setting of the viewfinder changeable, so that only the lens associated focal length can be used therein.

It is advantageous to set the viewfinder field mask with a special mask coupled in front of the lens bayonet, so that in each position different groups of bayonet grooves which correspond to the arrangement of the coupling parts on the various lenses.

In this way the user of the camera is forced to crop the viewfinder image set correctly for the lens to be used, otherwise this lens would not be used at all can insert into the holder on the camera.

The subject of the invention is shown in the drawing, namely shows

Fig. Ι a front view of the camera without lens,

Fig. 2 is a plan view of the partially cut-open camera,

Fig. 3 is a plan view of the camera with a different mask adjustment device,

Fig. 4 another embodiment / form of the viewfinder field diaphragm,

Fig. 5 a further embodiment of the field diaphragm,

Fig. 6 is a plan view of the mask adjustment device according to Fig. 5 and

Fig. 7 to 9 rear views of the interchangeable lens mounts with their coupling attachments for the interchangeable version.

The various objectives 0 can be inserted into the interchangeable mount k ^1. Switchable masks m are arranged in the viewfinder j. The mask carrier t can be designed as a slide according to Fig. Ι and is guided ^{on the inside ß 4 of} a cap k ² placed on the narrow longitudinal wall k ^{5 of} the camera k in longitudinal slots t ² on pins t ^s. This mask carrier is operated according to Fig. Ι by a button i ⁴ , which through slots k ^e from the front wall k ³ after

*) The patent seeker stated as the inventor:

Dr. August Nagel in Stuttgart.

protrudes outside. However, according to Fig. 3, near the viewfinder j ^1, a slider i ¹ provided with teeth £ ^{ä can be} arranged, which at one end t ⁷ with the slot J ^; is guided on a pin f , while cfie. Guide at the other end i ¹⁰ through the Steji ^ button i ⁴ and the slot k ^a in the cap ^ ". ' cover ^{7 is} formed.

The mask carrier ί is provided with a toothed rack £ ^e , the toothing s of which engages with the toothed circumference s ^{1 of} a mask a , which can be rotated around the optical axis in front of the bayonet ^{ring / e 1 of} the lens carrier and which optionally with its notch α next to the permanently accessible bayonet slots -r ⁴ and x ⁵ releases either the slot x ^x or x ² or x *. ^{Correspondingly, there are offset bayonet lugs o 1} to o ⁵ on the various interchangeable lenses (Figs. 7, 8, 9), which correspond to the slots x ¹ to x ^s , in such a way that each of the slots χ ¹ , χ- and x ^a only one nose o ¹ , o ² and o ^{8 are} each assigned to different lenses, while each lens has noses 0 * and v ^s , which correspond to the slots .t ⁴ and x ^5. The mask openings m are arranged on the mask carrier in such a way that in each mask position only one of the bayonet ^{slots x 1} , x ^z or x ^{3 is} released, while the slots x * and x ⁵ in each position of the mask ring α according to its corresponding recess (Fig. 4 and S) are accessible. In the position of the ringesa, only the lens (Fig. 8) can therefore be inserted into the bayonet slots x ^% , x * and x ⁵ with its noses o ² , o ⁴ and o ⁵ . The middle viewfinder field mask is assigned to this lens (Fig. 8). If the left mask m (Fig. 1) is now brought into the operating position, ie in the viewfinder field of view, ^{by moving the button i 4} to the right, the toothed rack s of the mask carrier ί rotates via the toothing 2 ¹ the bayonet mask a, which is shown in the Recess k ^{8 of} the lens carrier k ^{1 is} mounted, whereby the notch a ^{1 is brought} to overlap with the recess x ^{1 of} the lens holder k ¹ .

The lens according to FIG. 7 can now be inserted with its noses o ¹ , o ⁴ , o ^s into the exposed bayonet slots x ¹ , x ⁱ , x ⁵ and fastened in the usual way by twisting.

If, on the other hand, the lens according to Fig. 9 with the shoulders o ³ , o ⁴ , o ^{5 is} to be inserted into the bayonet ring k ¹ , the mask carrier ί on the button i ⁴ must be pushed to the left, whereby the smallest image field mask is in front of the viewfinder opening s ² is brought. As a result, the recess a ^{1 of} the bayonet mask α is automatically brought into overlap with the recess x ^s .

To the mask support not exactly in the three operating positions to bring a locking pawl is provided which y about a pivot, can .schwingen and sled by a spring / ¹ with ■ piiiem end i ¹¹ in abutment with the Maskenf t or the bayonet mask i ¹ held * rwitd so that it engages ^{in the notches i 12 in the various operating positions.}

Instead, the pawl t ^{i2 can advantageously be designed as a double-} sided locking pawl which can be actuated by means of the pin i ¹³ which protrudes outward ^{through the slot Vc 0} of the cap k-.

In Fig. 3 an indirect actuation of the viewfinder field slider is shown, which is driven by a gear shaft s ⁱ , s ⁵ from the toothing s ^{2 of} the actuating slide t . This shaft s ⁱ is advantageously under the influence of a helical spring f which returns all adjustable parts to an initial position when the lock i ¹¹ , i ^{12 is triggered.}

According to Figs. 4 to 6, a revolver can be used instead of the viewfinder mask slider t , which can be turned by the crank h via the gear transmission 2 ^% , s ^s . The button i ^{4 of} the crank h is advantageously designed as a resilient locking pin which can snap into bores u , whereby the crank can be fixed in the various angular positions that correspond to the various adjustments.

Claims (6)

'Patent claims: 1. A photographic camera with interchangeable lenses of different focal lengths and a viewfinder with variable image field limitation, characterized in that the holding device (x) of the lens on the camera inevitably depends on the mask setting (i) is variable so that only the lens of the associated focal length can be used therein is. 2. Photographic camera according to claim i, characterized in that the mask setting of the viewfinder image field with a mask (α) in front of the lens bayonet (x) is coupled, so that in each position other groups of bayonet grooves {x ¹ , x ² , x ^s ) , which corresponds to the arrangement of the coupling parts (0 ¹ , o ² , o ³ ) on the various lenses (0, Fig. 7, 8, 9). 3. Photographic camera according to spoke i, characterized in that the Carrier (i) of the picture window masks (w) as Turret disk or drum is formed. 4. Photographic camera according to one of claims 1 to 3, characterized in that the operating element (Z ⁴ ) for the mask adjustment through a gear with both masks (m, a) is connected. 5. Photographic camera according to one of claims 1 to 4, characterized by a latching or locking device which is effective in each case in the correct operating position of the masks (m, a) on the adjusting device (i ⁴ ). 6. Photographic camera according to one of claims 1 to 5, characterized by a return spring (/) which acts on the masks in the sense of a return in an original position acts. For this 1 sheet of drawings