Untitled record

The invention relates to a viewfinder light shaft for photographic cameras with a Reflexeinstellsucherkammer arranged over the recording camera.

Such cameras are provided, inter alia, with adapter devices, in addition to the full image format z. B. also allow smaller images on perforated 35 mm film permit. In this case, a Bildfeldbegrenzungsrahmen is inserted into the recording camera and at the same time mounted a mask on the screen of the Einstellsuchers. So far, such Sucherbildmasken were placed on top of the screen, keeping their proper attitude in the usual camera pose. In transverse views, ie in vertical position of the screen or the other pivoting of the camera, it could happen that they fell out. To the same extent, this applies to other accessories or accessories that are used interchangeably in conjunction with the Reflexeinstellsucherkammer, such as field lenses, V-grid plates, filters, polarizing films u. like.

The invention provides a holding device for such replaceable accessories to be created, which securely holds these parts in their proper position without affecting the easy interchangeability. Furthermore, the holding device should be fully effective, without the simple form of previously insertable masks, lenses, filters, films u. like. something needs to be changed, and finally, this purpose is to be achieved without compromising the use of the entire screen area for the full image format. According to the invention above the ground glass on one side of the ground glass frame projections for pushing one edge of a mask od. Like. provided, and on the other side are just such, but movable projections that od by an external operating handle together or individually from the area of ​​the mask. Like. Can be brought.

Preferably, these projections are formed as terminals with S-shaped cross section, which are pivotable about an axis parallel to the screen edge, wherein one of the ends engages as a projection on the ground glass, while the other end protrudes as an actuating button out of the ground glass frame to the outside. In this embodiment, it is advantageous to connect the clamping spring adjacent to the clamps, which must be present in any case to hold the ground glass in contact with the light shaft, with the terminals in order to keep them in their operating position.

In another embodiment of the subject invention, an elongated spring is attached, the bends of which protrude at the two free ends in the region of the ground glass, wherein the spring between two lugs of the ground glass frame is mounted, so Däß by pressure on the center of the spring their free ends be bent out of the range of the screen. Preferably, a resting on the center of the spring button is attached, which projects through the light shaft frame to the outside and is prevented by this falling out to the outside.

In the drawing, two example embodiments of the subject invention are shown, in which Fig. I shows a vertical cross section through the top of a camera with ground glass hood with inserted viewfinder mask, Fig.2 shows an enlarged section through a pivotable retaining clip in the operating position, Fig. 3, a Plan to Fig. 2, Fig. 4 the same clamp in inoperative position, Fig. 5 the plan of a second embodiment in the operating position and Fig.6 the same arrangement as in Fig.5, but in an inoperative state.

In the upper part of the housing i of the viewfinder camera is the Suchermattscheibe 2 approximately for an image format 6 X 6 cm, which is shielded from above through the light shaft 3 against disturbing side light. In the case of small-image shooting on perforated 35 mm film is in Gien light well 3, a field mask 4 with the image opening 5 for z. B. 24 X 36 mm inserted, which is stuck with the front under solid protruding tabs 6 and overlapped on the back of the one or more lobes 7 a movable retaining clip 8. The ground glass 2 is pressed in Fig. Z by a flat spring 9 from below resiliently against a guide frame io of the light shaft. This flat spring g is usually riveted to bent lobe ii on the frame io. Instead of riveting, it is held in the present case in the area of ​​the brackets 7 by I the head i2 of a projection 13 which is bent from the actuating button 8. By a pin 14, the movement of the key 8 is limited to the inside, with an elastic contact between the key 8 and the pin 14 is ensured by oblique bending of the spring tabs ii. At the top, the key 8 is provided with one or several tabs 7 engaging over the screen, which rest on the mask 4 in the normal position and, in conjunction with the tabs 6, hold the mask on the screen. If now pressed in the direction of arrow A on the key 8, the head i2 presses on the spring 9 and biases it, while at the same time the projection 7 is pivoted out of the region of the mask 4, so that the mask can now be pulled out under the flap 6 , When you release the key 8 is returned under the influence of the spring 9 back into the position shown in Fig. 2.

In Fig. 5 and 6, a second embodiment is shown in which as a holding device for the mask 4, the bends 15 of the free ends of a spring 17 protrude out of the shaft wall 16 on the screen or mask 4. The connecting web 17 of the two spring ends is straight and lies between fixed bends 18 of the housing and a guide groove i9 a key 2o (see Fig. 5). If now pressed in the direction of arrow B on the key 2o, the spring 17 is deflected in the middle, whereby its two ends 15 in the wall 16, ie from the area of ​​the mask 4, are pulled. Conversely, when the key is released, the projections 15 return to the area of ​​the ground glass screen and can overlap and hold the mask here.

It is obvious that in the same way other accessories and accessories in place of the field mask can be connected to the ground glass, such as field lenses, lens and V-shaped plates, filters, films and. like.

Moreover, the outwardly resiliently protruding button 8, 2o can be used for locking other additional parts that are placed outside the light shaft, such. B. additional slip-on light shafts made of leather, so that it is unnecessary by the invention for this purpose a special locking device.