JPH041334B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a blade type focal plane shutter.

In blade-type focal plane shutters, in order to reduce the setting force or increase the curtain speed, it is effective to reduce the area of each shutter blade and reduce its weight. Since the amount of overlap of the blades is reduced, this is disadvantageous in terms of light blocking performance. For this reason, JP-A-52-
According to Publication No. 96019, after the shutter trailing blade has finished traveling, the leading blade is returned to the picture frame and the leading blade and trailing blade double cover the picture frame, and the trailing blade also retracts from the picture frame when the shutter is set. Similarly without the leading vane,
A shutter has been proposed in which both trailing blades cover the picture frame twice, and in connection with the shutter release, the trailing blade first retreats from the picture frame, and then the leading blade starts traveling. However, this mechanism is complex.

In view of the above-mentioned problems, the present invention aims to provide a focal plane shutter that has a simple mechanism, has the same function as the conventional one, and has high light-shielding properties even when the amount of overlap of each blade is reduced. However, this will be explained based on an example illustrated below. FIG. 1 shows a shutter blade opening/closing mechanism of an example of a focal plane shutter of a single-lens reflex camera with a built-in winder according to the present invention. FIG. 2 is a schematic plan view of the vehicle, showing the mirror-down state after the shutter is running. FIG. 5 is a left side view of the mirror box in the state shown in FIG. 1, which is disposed on the substrate of the focal plane shutter shown in FIG. 1, and the right side is the photographing lens side.

In FIG. 1, reference numeral 1 denotes a substrate on which an aperture 1a is formed, and 2 forms arm portions 2a and 2b, which are rotatably supported by a shaft 3 fixed to the substrate 1 and supported by a spring 4. Therefore, the arm portion 2b of the leading blade set lever is provided with dextrorotation and is restrained by coming into contact with a pin 23c of the set lever 23, which will be described later. 5 forms a hook portion 5a, is pivotally connected to a shaft 6 fixed to the base plate 1, is given levorotation by a spring 7, and can be prevented from turning to the left by coming into contact with a stopper pin 8. 9 is a hook portion 9a that can be engaged with the hook portion 5a of the first locking lever 5;
A vane pin 9b and a set pin 9c are implanted therein, and it is pivotally connected to a shaft 10 fixed to the base plate 1, and left rotation is imparted by a spring 11, but the left rotation is prevented by contacting a stopper 12. This is the leading blade drive lever. The feather pin 9b
is connected to a leading blade group (not shown) by well-known means, and in the state shown in FIG. 1, the leading blade group is folded above the aperture 1a. 13 is the arm part 13
a, 13b and a pin 13c on the arm portion 13a.
The spring 1 is pivotally connected to the shaft 3.
4 imparts dextrorotation, but the arm portion 13b
The rear blade set lever 16 is prevented from rotating clockwise by coming into contact with a stopper pin 15. The rear blade set lever 16 forms a hook portion 16a, and is pivotally connected to a shaft 17 fixed to the base plate 1, and is imparted with left rotation by a spring 18. 20 is a hook portion 1 of the rear locking lever 16, which is designed to be able to prevent left rotation by contacting the stopper pin 19, but is kept in the unlocked state by well-known means.
A hook part 20a that can be engaged with the base plate 1 is formed, and a feather pin 20b and a set pin 20c are implanted therein, and the spring 22 is pivotally connected to a shaft 21 fixed to the base plate 1.
This is a trailing blade drive lever that is given levorotatory properties by the following, but its left rotation is restrained by a stopper pin (not shown). The blade pin 20b is connected to a rear blade group (not shown) by well-known means, and in the state shown in FIG. 1, the rear blade group is expanded so as to cover the aperture 1a. 23 is an arm portion 23a, 23
b, and a pin 23c is implanted on the arm portion 23a, and a pin 23d is implanted on the arm portion 23b. Although it is given, the arm part 2
3b is a set lever whose levorotation is suppressed by contacting a stopper pin 26, and 27 is a slide lever which forms a bent portion 27a and is adapted to slide to the left in conjunction with film winding. Furthermore, in FIG. 5, reference numeral 31 indicates a mirror box side plate in which an escape groove 31a is formed;
Forms a bent portion 32a and an arm portion 32b, and is pivotally connected to a shaft 33 fixed to the side plate 31, and is given dextrorotation by a spring 34. The dextrorotation of the shaft is suppressed by a stopper pin 35. The first locking lever is controlled by the shutter release operation. A shaft 3 36 forms a hook portion 36a and an arm portion 36b, and is fixed to the side plate 31.
7 and is provided with dextrorotation by a spring 38, and the right rotation can be inhibited by contacting a stopper pin 39, but by pressing down the arm 36b with a member not shown, the right rotation can be prevented. A second locking lever whose rotation is inhibited is controlled in conjunction with the movement of the rear blade group. 40
forms arm portions 40a, 40b and a bent portion 40c, and is pivotally connected to a shaft 41 fixed to the side plate 31, and is given levorotation by a spring 42; A charge lever 44 is prevented from rotating to the left by contacting the hook portion 44a and the bent portions 44b, 44.
c, it forms a surface 44d and is pivoted to the shaft 41 and given dextrorotation by a spring 45, but the right rotation is inhibited by the bending portion 44b coming into contact with the arm portion 40b. control lever, 4
6 has a pin 46a planted therein and the side plate 31
The pin 46a is pivotally connected to a shaft 47 fixed to the surface 4, and is given dextrorotation by a spring 48.
4d, which prevents its right rotation (corresponding to the state shown in Fig. 1).
In the state shown in the figure, the mirror 46 is in the down position and reflects the photographing light that has passed through the photographic lens and guides it to the viewfinder. 49 is a bent portion 49a, a curved surface 4
9b, which is pivotally connected to the pin 46a and given dextrorotation by a spring 50; 49a is an interlocking lever that is in contact with the pin 13c of the rear blade set lever 13.

Since the focal plane shutter according to the present invention is constructed as described above, when the film winding operation is automatically performed immediately after photographing is completed and the mirror is in the down state, the slide lever 27 is moved in conjunction with this. As the set lever 23 is rotated to the right against the tension of the spring 25 by sliding to the left in FIG. Press. Then, the leading blade set lever 2 rotates to the left against the tension of the spring 4, and its arm 2a pushes the set pin 9c of the leading blade drive lever 9, so the leading blade drive lever 9 rotates to the right against the tension of the spring 11. (Figure 2). Further, since the charge lever 40 is also rotated to the right in FIG. 5, the springs 42 and 45 are charged, and the charge lever 40 is restrained by its bent portion 40c engaging with the hook portion 36a of the locking lever 36, and the mirror charge is stopped. state (Figure 6). At this time, both the leading blade group and the trailing blade group are at aperture 1.
It covers part a and enhances the light-shielding properties. In FIG. 2, the slide lever 27 continues to move to the left, but after the film winding operation is completed, it slides to the right as shown by the chain line and returns to its original position.

Next, when the shutter button is pressed, the first locking lever 32 is rotated to the left against the tension of the spring 34 as shown in FIG. The engagement is released. Therefore, the unlocked control lever 44 is rotated to the right by the restoring force of the spring 45 in the charged state, and the surface 44d is aligned with the pin 46a of the mirror 46.
, the mirror 46 is rotated to the left and brought into the up position (FIG. 7). on the other hand,
The interlocking lever 49 is also moved upward with the displacement of the pin 46a, and its bent portion 49a pulls up the pin 13c of the rear blade set lever 13, so that the rear blade set lever 13 is rotated to the left against the tension of the spring 14. Then, the arm portion 13b of the rear blade set lever 13 pushes the set pin 20c of the rear blade drive lever 20, so the rear blade drive lever 20
is rotated to the right against the tension of the spring 22, and its hook portion 20a engages with the hook portion 1 of the rear locking lever 16.
6a (Figure 3). FIG. 7 shows a state in the middle of operation, in which the mirror 46 has not yet completed its raising, but the trailing blade drive lever 20 is already in the overset position. Thereafter, the control lever 44 continues to rotate to the right, and its bent portion 44b comes into contact with the arm portion 40b of the charge lever 40 and stops, and at this time the mirror 46 has completed its upward movement (FIG. 8).
Further, the curved surface 49b of the interlocking lever 49 is connected to the pin 51.
Since the rear blade set lever 13 moves upward while remaining in contact with the rear blade set lever 13, the bent portion 49a is disengaged from the pin 13c of the rear blade set lever 13 at the final stage of mirror up. Therefore, the rear blade set lever 13 rotates clockwise and returns due to the tension of the spring 14, and as a result, the pressing force of the arm portion 13b on the set pin 20c of the rear blade drive lever 20 is released, so that the hook portion 20a is rear-locked. It is locked by the hook portion 16a of the lever 16 (FIG. 4). At this time, only the leading blade group covers the aperture 1a, and the trailing blade group is displaced to the start position.

Thereafter, when the tip locking lever 5 is turned to the right by a well-known means, the engagement between the hook portion 5a and the hook portion 9a of the tip blade drive lever 9 is released, and the disengaged tip blade drive lever 9 is It is rotated to the left by the restoring force of the spring 11, and is stopped by coming into contact with the stopper pin 12. Therefore, the lower blade group is folded above the aperture 1a to open the aperture 1a and exposure is started (Fig. 1), but at this time the rear blade group is restrained at the starting position (Fig. 4). ).

Thereafter, when the rear locking lever 16 is turned to the right by the known means after the appropriate exposure time has elapsed, the hook portion 16a of the rear locking lever 16 and the hook portion 2 of the rear blade drive lever 20 are rotated.
The disengaged rear blade drive lever 20 is rotated to the left by the restoring force of the spring 22, and is stopped by coming into contact with a stopper pin (not shown). Therefore, the rear blade group is aperture 1.
One exposure is completed by expanding to a position covering aperture 1a (Fig. 1), but at this time the leading blade group is
remains open. Note that the first locking lever 5 and the rear locking lever 16 are connected to springs 7 and 18 after releasing the lock, respectively.
The tension causes it to rotate to the left and return to its original position.

As described above, when the rear blade group closes the aperture 1a, the second locking lever 36 is rotated to the left at the same timing. This is normally linked to the final operating range of the trailing blade drive lever 20. By turning the second locking lever 36 to the left, the engagement between the hook portion 36a and the bent portion 40c of the charge lever 40 is released, so that the charge lever 40 is moved to the control lever 4 by the restoring force of the spring 42.
4 and is rotated to the left. As a result, the mirror 46 whose pressure is released is rotated to the right by the restoring force of the spring 48 and returns to the down state (fifth
figure). On the other hand, as the control lever 44 rotates to the left, the interlocking lever 49 descends and returns to its original position. after that,
The charge lever 40 is prevented from rotating to the left by its arm 40a coming into contact with the stopper pin 43, and the charge lever 40 returns to the state shown in FIG. At this time, only the rear blade group covers the aperture 1a.

This completes one photographing operation, but since the film winding operation is automatically performed immediately after the photographing is completed, the leading blade group also covers the aperture 1a as described above (FIG. 2).

As described above, in the focal plane shutter according to the present invention, both the leading blade group and the trailing blade group always cover the aperture when the mirror is in the down state.
In addition, the leading blade driving spring is configured to be charged when the leading blade is returned in conjunction with the automatic film winding operation that accompanies the end of the photographing operation, and the trailing blade driving spring is charged when the trailing blade is retracted. Although it has a simple structure, it has the same functions as conventional ones, and also allows the shutter blade to run stably, reducing uneven exposure and improving durability.
Moreover, it has the effect of providing high light-shielding properties.
Furthermore, since the rear blades are retracted to the start position when the mirror is raised, the operating time can be shortened.

[Brief explanation of drawings]

FIG. 1 is a schematic plan view of the shutter blade opening/closing mechanism of an actual example of the focal plane shutter according to the present invention, FIGS. The figure is the first example of the above example.
Side view of the mirror box in the state shown, No. 6
8 to 8 are diagrams showing the course of displacement of the mirror in the above-mentioned actual rotating example. 1... Board, 2... Lead blade set lever, 5...
...Tip locking lever, 9...Top blade locking lever, 13
... Rear blade set lever, 16 ... Rear lock lever, 20 ... Rear blade drive lever, 23 ... Set lever, 27 ... Slide lever, 31 ... Mirror box side plate, 32 ... First lock lever, 3
6... Second locking lever, 40... Charge lever, 44... Control lever, 46... Mirror, 49
...Interlocking lever.

Claims (1)

[Scope of Claims] 1. A leading blade drive whose operation causes the shutter leading blade to open and close with respect to the picture frame, and in which the leading blade drive spring is stored and charged at a position where the leading blade covers the picture frame. A lever, and a rear blade drive lever whose operation opens and closes the shutter rear blade with respect to the image frame, and the rear blade drive spring is charged by accumulating energy at a position where the rear blade is retracted to a starting position outside the image frame. a mirror that can take a down position and an up position and is biased to the down position, a slide lever that is linked to the film winding operation, and a position where the leading blade covers the picture frame in conjunction with the operation of the slide lever. A leading blade set lever that pushes the leading blade drive lever, and a leading blade set lever that is pressed by the mirror and interlocks with its reciprocating rotation to move the mirror to the up position and down position.
In conjunction with the operation of the rear blade drive lever to cover the image frame, the pressure on the mirror is released, returning the mirror from the up position to the down position, and in conjunction with the operation of the slide lever, the mirror from the down position is moved toward the up position. a control lever that is controlled to a charge state to bias the control lever; a first locking lever that locks the control lever in the down position of the mirror and releases the lock in response to the shutter release; In conjunction with the operation of raising the rear blade, the trailing blade set lever is pushed to a position where the trailing blade is retracted outside the image frame, and the leading blade driving lever in the charged state is locked and released. The front locking lever, which opens the leading blade to start exposure, and the trailing blade drive lever in the charged state are locked, and by releasing the locking, the trailing blade covers the image frame. A focal plane shutter equipped with a post-latching lever that allows you to complete the exposure by pressing the button.