DE1040365B - Device for photographic roll film focal plane shutter cameras - Google Patents

Description

The invention relates to a device for photographic roll film focal plane shutter cameras by means of depending on the actuation of the focal plane shutter, a pressure plate on the in the area the part of the roll film lying on the focal plane window for the purpose of a flat mounting of the same, pressed or lifted from it for the purpose of unhindered further transport of the film will.

There are cameras known that with a film ίο pressure plate are provided to hold the film flat during exposure. The known devices however, cannot solve the problem in question in a completely satisfactory manner to solve. For example, devices are known in which a cam, which the pressure plate controls, is coupled to the film winding device. Because the cam with the film winding device is rigid rotates, the film pressure plate still presses on the film at the beginning of the film advance, which causes the film can be scratched. In another device, the film pressure plate is of the Lock release button pressed. With this device, the pressure plate presses the film flat, just before an exposure occurs. Since it generally takes a certain period of time until the pressure plate has laid the film flat, with these devices the film lies during the exposure not stable enough yet. Furthermore, this device has the disadvantage that to actuate the release button as a result of the coupling of the same with the pressure plate, a considerably higher expenditure of force is required is. This can lead to “blurring” of the picture, especially if the exposure times are not too short come.

According to the invention, these disadvantages of the known device are now avoided in that the coupling of the pressure plate with the focal plane shutter is effected by a lockable pawl will. The pawl is at the end of the process of the focal plane shutter by a with This actuating member connected in a motion-locking manner is brought into a position in which it holds the pressure plate lifts off the film against spring pressure. In this lifted position, it is spring-loaded Locking member locked. The locking member then gives when the tensioning process is completed the focal plane shutter and the further switching of the film transport the pawl underneath the action of a part connected in a motion-locking manner to the focal plane shutter, so that the Pressure plate is pressed against the film by the spring.

Exemplary embodiments are shown below

for photographic

Roll film focal plane shutter cameras

Applicant:

Canon Camera Company, Incorporated,
Tokyo

Representative: Dr. Dr. R. Herbst, lawyer,
Fürth (Bay.), Breitscheidstr. 7th

Claimed priority:
Japan December 20, 1954

Hiroshi Suzukawa, Tokyo,
has been named as the inventor

forms of the subject matter of the invention described in more detail in conjunction with the drawings. It shows

Fig. 1 is a plan view with the pressure plate lifted, i.e. H. is not pressed, with a Arrangement in which the pressing and releasing of the film by a film pressure plate in Connection with the winding movement of the second roll-up sheet happens,

FIG. 2 is a plan view showing the film in FIG Focal plane held shows

3 shows a plan view of another embodiment arm with the pressure plate lifted, the arrangement is made so that the pressing in connection with the actuation of the closure winding drum happens

FIG. 4 shows a plan view of the arrangement shown in FIG. 3, but when it is pressed on by the pressure plate Movie.

1 and 2 show an arrangement in which the pressure plate is actuated in connection with the winding movement of the second roll-up cloth, with 1 a mask frame guiding the film, 2 a pressure plate, 3 a pressure spring for the pressure plate, 4 a closure winding drum, 5 a winding drum for the first roll-up cloth and 6 denotes a winding drum for the second roll-up cloth. A pin 7 is provided under the pressure plate 2 or at any other suitable location which enables the film F to be moved past. On an axis 9, a lever 8 is attached through which the

«09 64W162

Pressure of the pressure plate 2 on the film F can be canceled by exerting pressure on the pin 7 against the action of the spring 3. A pin 14 is also provided on a rotatable disk 13, which is positively connected to the winding drum for the second S roll-up cloth, in such a way that it can communicate a rotary movement to another arm 15 of the lever 8. A stop arm 17 is designed and arranged so that it can come to rest on a shoulder 16 of the arm 15 under the action of a spring 18. This contact relationship can be canceled by a deflection pin 19 fastened on the rotatable disk 13.

Fig. 1 shows the state when the shutter has finished the exposure operation. The pin 14 presses in this case on the arm 15 of the lever 8, which in turn presses on the pin 7 to lift the pressure plate 2 against the action of the spring 3, so that the film F is no longer pressed and is therefore held loosely . When the closure winding drum 4 is rotated in the direction of the arrow by the positive connection with the film winding mechanism, both the first and the second roll cloth are wound at the same time, so that the rotatable disk 13 can also rotate in the direction of the arrow. Immediately after the initiation of the winding process, the pin 14 releases the arm 15, while the lever 8 remains in its original position, the film being released by the attachment of the attachment 16 on a step 20 provided on the stop arm 17, which is below the effect of the spring 18 is. At the end of the locking process, another pin 19 fastened to the rotatable disk 13 comes to rest on the stop arm 17, whereby the latter is pivoted into the position shown in FIG. seen in the drawing, is pivoted counterclockwise, whereby the pressure plate 2 is released so that it is pressed under the action of the spring 3 and thus the film is held in the focal plane in contact with the mask frame 1. During the closing movement of the shutter, the rotatable disc 13 is set in rotation by the winding movement of the second roll-up cloth, so that the pin 19 is moved away from the stop arm 17, which has the consequence that the stop arm 17 moves back, but in this stage the lever 8, 15 is held in its original position in which the pressure plate is released as a result of the contact of the projection 16 on the shoulder 22 on the side of the step 20. At the end of the winding process of the second roll cloth, the pin 14 presses on the arm 15, whereby this is returned to the position shown in Fig. 1, so that the pressure plate 2 releases the film. In other words, at the end of the film advancing and closing voltage process, the film is pressed by the pressure plate, while the pressure plate is lifted at the end of the exposure process, whereby the film is released.

3 and 4 show another embodiment in which the lifting of the pressure plate for the release of the film takes place in a manner similar to the embodiment shown in FIG. 1 in connection with the winding movement of the second roll-up sheet. In this embodiment, a reciprocating rod 23 is provided for engagement with the lever 8. When these two parts are in engagement, a nose 24 at the left end of the rod 23 presses on the lever 8, the rod 23 being held in this position by a spring 27. At the lower end of the drum 4 (or on a suitable part which is fixed on the axis of this drum and which rotates with the latter), a lug 25 is provided. When the closure tensioning process is completed, the projection 25 comes to rest against a curved part 26 of the right end of the reciprocating rod 23, as a result of which it, as seen in the drawing, is pulled to the right, with the result that the nose 24 disengages comes with the lever 8, so that this moves into the position shown in Fig. 4 and therefore the pressure plate 2 is pressed against the film. When the exposure is initiated by the shutter, the projection 25 revolves in the direction of arrow b , with the result that the reciprocating rod is moved to the left under the action of the spring 27 so that it is on top of the lever 8 comes to rest, because at the end of the exposure through the second roller cloth as a result of the orbital movement of the pin 14 in the direction of arrow C from the position shown in dashed lines in Fig. 3 has meanwhile been moved into the position shown in full lines. In the event of a slight delay in the rod, the nose 24 slides under the lever 8, so that the pin 7 is pressed in for the lifting of the pressure plate 2.

Claims (3)

P A T E N T A N S P R Γ C H K 1. Device for photographic roll film focal plane shutter cameras, by means of which, depending on the actuation of the focal plane shutter, a pressure plate is attached to the in the area of the focal plane window lying part of the roll film pressed for the purpose of a flat holder of the same or lifted from it for the purpose of unhindered onward transport of the film is, characterized in that the coupling of the pressure plate (2) with the slot shutter is effected by a lockable pawl (8, 15), which at the end of the process of the focal plane shutter by an actuating member connected to it in a motion-locked manner (14) is brought into a position in which it is against the pressure plate (2) from the film (F) Spring pressure (3) lifts off and in which it is locked by a spring-loaded locking element (17) is, and that the locking member (17) at the end of the tensioning process of the focal plane shutter and indexing the film transport under the action of one with the focal plane shutter motion-locking connected part (19, 23) releases the pawl, so that the pressure plate (2) is pressed against the film by the spring (3). 2. Apparatus according to claim 1, characterized in that on one of the winding drum (6) for the first roller cloth of the focal plane shutter rotatably connected disc (13) two pins (14, 19) sit, one of which (14) when the focal plane shutter expires a rotatably mounted angle lever (15, 21) pivoted, which lifts the pressure plate (2) from the film (F) , while the other pin (19) at the end of the tensioning process of the focal plane shutter triggers a locking lever (17), which is triggered by the Effect of a spring (18) with a nose (20) in front of an approach (16) of the angle lever (15, 8) when 1 U4U Pivoting the same has placed and so the angle lever until it is triggered in the position has held in which the pressure plate is lifted from the film (Fig. 1 and 2). 3. Device according to claims 1 and 2, characterized in that a longitudinally displaceable Latch (23) is provided, which of a pin (25) on the winding drum (4) for the second The roll-up cloth of the focal plane shutter is triggered. Considered publications: German Patent Specifications No. 515 422, 553 451. 1 sheet of drawings © «19 640/162 9.5»