DE1165991B - Swing shutter for photographic camera, the shutter plate of which is influenced by an anchor arrangement - Google Patents

Description

Swing shutter for photographic camera, its shutter plate is influenced by an armature arrangement. The invention relates to a swing lock for photographic cameras with an opening around a pivot point shutter plate rotatable under the action of an actuating force, and relates to such a shutter in which the moving speed of the shutter plate is influenced by an anchor arrangement.

There is known a shutter for photographic cameras in which the exposure time is determined by the shutter plate for the exposure aperture is connected to an armature arrangement, similar to the armature mechanism of a clock, where the speed of the repeated anchor swings and thus the speed of rotation the locking disc, in whose teeth the armature engages, by a corresponding one Change in the spring tension can be influenced.

In this known device, the inhibition of movement takes place continuously and uniform all the way through the shutter plate. This makes this well-known Arrangement only for relatively low shutter speeds, i. H. for long exposure times, suitable. In addition, the arrangement is due to the necessary precision of the anchor parts relatively expensive and time-consuming.

The subject of the invention, however, is cheap and simple Cameras to train the shutter so that the function of the shutter in three Phases of movement is split up by first opening quickly, then one is kept open for a certain time and then quickly closed again. According to the invention This object is achieved in that an anchor plate with an arm so in the Movement path of the closure plate lies in that this is under the action of the actuating force in the first phase of their movement until essentially in the open position of the closure moves freely and strikes the arm, in the second movement phase this is the one for its pivoting out of the trajectory necessary energy in a predetermined Time span transfers, and in the third movement phase up to the closed position swings through freely.

According to the known rotary lock, in the functional position the Anchor escapement a uniform braking of the movement over the entire movement path, while according to the inventive arrangement of the anchor part the advantage is achieved will. that not, as with the known lock, creeping open and closed is, but that in the first movement phase is opened quickly, then in the second movement phase almost during the full opening the inhibition by the Anchor plate takes place and quickly closed again in the third movement phase will. In both cases, the armature is used to control the rotary movement, however, there is an essential difference between the known embodiment on the one hand and the embodiment of the invention on the other hand in that when Did you know the anchor escapement only with long exposure times? Closure should and can delay, while according to the invention of the anchor each closure sequence is effective for its subdivision into three phases.

In a preferred form of further training, there is another arm of the Anchor plate during the movement on a guide surface of the closure plate to the is designed so that the first arm of the armature to pivot in the for Transmission of the kinetic energy in the required position in the predetermined period of time is held. To limit the pivoting movement of the anchor plate on both sides two stops can be provided.

The invention is based on the drawings using an exemplary embodiment explained in more detail.

F i g. 1, 2 and 3 show schematically the swing lock according to the invention in its three phases of movement.

In the figures, 1 denotes the plate of the closure with the diaphragm 2 in the middle; the shutter blade 3 can be pivoted about a pivot pin 4 and is stationary under the action of a helical spring 5 which causes the same to trip; in of the lamella 3 an opening 6 is also provided, which serves to to determine the opening time of the shutter by sliding in front of the diaphragm 2. A brake plate 7 is freely pivotable about a pivot pin 8, with its pivoting movement is limited by two stops 9 and 10 on both sides.

The brake plate 7 has two protruding curves at its ends 11 and 12, their shape and position with respect to the shutter blade 3 the aforementioned Condition the effect of the platelet.

If the closure is now in the ready position, i. H. can be triggered (FIG. 1), the lamella 3 is supported on the curve 11 and holds the brake plate 7 against the stop 9, while a large part of the Rounding 12 of the brake plate protrudes into the sliding area of the lamella 3 at the same time.

When the release occurs, the shutter blade 3 begins to move to the right under the action of the spring 5. During the first section of this movement path, namely before the diaphragm is released through the opening 6; the edge of the lamella 3 slides on the rounding 11 of the brake plate 7 (FIG. 2), whereby the latter remains immovable in its initial position; shortly before the lamella 3 hits the rounding 12 of the plate 7 ( FIG. 2), the other rounding 11 is released, so that the plate, as soon as its braking action begins by absorbing part of the inertia of the plate 3, its oscillation can complete the pivot pin 8 under the pressure of the lamella 3, the latter pressing the plate against the stop 10 at the end of its path of movement.

If the shutter blade 3 by a renewed release again after is returned on the left, the process described is repeated in reverse Direction, with an organ not shown in this last phase, the shutter closed holds.

By means of the device described, the shutter speed with a fixed load on the spring 5 in a simple manner by changing the Weight of the plate 7, can be adjusted as desired, with great accuracy, namely within ± 5%, as well as a permanent setting can be achieved. the cannot even be achieved with the expensive gear governors where a A tolerance of ± 30% must be regarded as normal. In summary it can be said be that the device according to the invention compared to the previously known and controllers used has the following advantages: lower manufacturing costs; simple Adjustment of the opening speed, which can also assume very low values; absolute constancy of the set speed; Uniformity of exposure time from the beginning to the end of the trajectory in front of the aperture.

Claims (3)

Claims: 1. Swing lock for photographic cameras with one provided with an opening around a pivot point under the action of an actuating force rotatable closure plate whose speed of movement is controlled by an armature assembly It is influenced by the fact that it is not possible to use an anchor plate (7) with one arm (12) lies in the path of movement of the closure plate (3) that this is under the action of the actuating force (5) in the first phase of its movement until essentially in the open position (F i g. 2) of the. The shutter moves freely and strikes against the arm (12), in the second phase of movement this for his Swiveling out of the path of movement required energy in a predetermined period of time transmits and swings freely in the third movement phase up to the closed position (Fig. 3). 2. Swing lock according to claim 1, characterized in that a other arm (11) of the anchor plate (7) during movement on a guide surface of the Closure plate (3) is applied, which is designed so that the first arm (12) of the Armature (7) to pivot in the for transferring the kinetic energy in the predetermined time required position (Fig. 1) is held. 3. Swing lock according to claim 1 or 2, characterized in that; that for mutual limitation the pivoting movement of the anchor plate (7) two stops (9,10) are provided. In Publications considered: German Patent No. 912 049.