JPS6141075Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a synchronized contact mechanism for a programmable electric shutter.

Since the aperture diameter of the program shutter varies depending on the exposure control status, when using a mechanical switch to synchronize the flash photography corresponding to each maximum aperture, conventional synchro switches were of the moving contact type. Therefore, the structure became complicated and stable operation could not be obtained.

The present invention is a programmable electric shutter.
By configuring the synchronizing contact with two contact pieces, and skillfully controlling the two contact pieces by the reciprocating movement of the opening/closing member that opens and closes the shutter blade and the reciprocating movement of the iron piece member that controls opening and closing. To provide a synchro contact mechanism that safely and reliably closes a synchro contact corresponding to each maximum opening time of a program operation, and prevents erroneous light emission.

Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings.

In Figures 1 to 5, 1a and 1b are an aperture formed on the shutter base plate (not shown) and a protrusion formed on the back side (not shown in Figure 2 and below).
It is. Reference numeral 2 denotes a set plate arranged so as to be movable in the left and right direction by shafts 3 and 4, and includes a rack 2a and a stepped portion 2.
b, a protrusion 2c, a flat portion 2d, and a bend 2e. A gear 5 is pivotally connected to a shaft 6, and is provided with a pinion 5a that meshes with a rack 2a of the set plate 2. Reference numeral 7 denotes a flywheel (not shown in Figure 2 and below) pivotally connected to the shaft 8, and a pinion 7 that meshes with the gear 5.
It is equipped with a. Reference numeral 9 denotes a spring 1 which is pivotally connected to the support shaft 2f on the set plate 2 and hung between it and the set plate 2.
It is a molded rocking lever that is given levorotatory properties by the angle 0, and has a pin 9a that can engage with the flat portion 2d of the set plate 2, an end surface 9b, and an arm surface 9c that are integrally formed. 11 is an electromagnet.

Reference numeral 12 designates an iron piece lever which is pivotally mounted on the shaft 3 and given left rotation by a spring 13 (not shown in FIGS. 2 and below), which can engage with the iron piece 12a facing the electromagnet 11 and the stepped portion 2b of the set plate 2. Also, the bending 12b that can be restrained by the protrusion 2c, and the pin 9 of the swing lever 9
An arm portion 12c that can push the arm 12a and a bent portion 12d into which an insulating member 12e is fitted are formed. 14 is an opening/closing lever pivotally connected to a shaft 15, and a swinging lever 9
It forms a bend 14a that can be engaged with the end surface 9b of the arm surface 9c and restrain the arm surface 9c, and also has one pin 14b on the front side and three pins 14c and 14d on the back side.
14e is planted. 16 is a spring supported by a pin 17 installed at a position apart from the shaft 15;
One end 16a is hung on the bend 2e of the set plate 2,
The other end 16b is hooked onto the pin 14b of the opening/closing lever 14, and acts as a force source for moving the set plate 2 to the right and as a force source for rotating the opening/closing lever 14 to the left.
Reference numeral 18 denotes a synchro contact piece A that is fixedly supported and is operated by bending 12d of the iron piece lever 12 via an insulating member 12e. 19 is pivotally connected to the shaft 4 and has a spring 20
(omitted below in Figure 2) is a synchro contact point B that is given levorotation, and the arm portion 19a limited to the stopper pin 21 and the pin 14 of the opening/closing lever 14.
It forms an arm portion 19b that can be pushed by the arm portion 19c.

The above-mentioned components are arranged on the front side of the shutter base plate (not shown), but the shutter blades that also serve as diaphragm blades and the related structure arranged on the back side will be described below. The pins 14d and 14e of the opening/closing lever 14 penetrate the arc-shaped grooves formed in the shutter base plate and protrude to the back side.

Reference numeral 22 designates one shutter blade, which is rotatably supported by a portion 22a, and is also supported by the opening/closing lever 14.
A long groove 22b into which the pin 14d is fitted, and a stepped portion 22c which abuts against the protrusion 1b of the shutter base plate to limit the amount of clockwise rotation thereof are formed. Reference numeral 23 designates the other shutter blade, which is rotatably supported by a portion 23a and has a long groove 23b into which the pin 14e of the opening/closing lever 14 is fitted, a warning light receiving window 23c, and an exposure control light receiving window 23d. are doing. 24
is the light receiving element, and the shutter base plate and shutter blade 23
is located between. 25 is shutter blade 2
This is a light introduction hole located on the back side of 3 (on the front side of the camera).

Next, the operation will be explained.

Although FIG. 1 shows the shutter mechanism in a stationary state, when the setting plate 2 is moved to the left against the tension of the spring 16, the swinging lever 9
The arm surface 9c is bent 14a at the opening/closing lever 14.
When the arm surface 9c comes off the bend 14a, the swinging lever 9 moves until the pin 9a is restricted to the flat surface 2d of the set plate 2 by the tension of the spring 10. Turning to the left, the end surface 9b becomes capable of engaging with the bend 14a, while the protrusion 2c
pushes up the bend 12b and rotates the iron piece lever 12 to the right against the tension of the spring 13, and the stepped portion 2b pushes up the bend 12b.
2b, the iron piece lever 12 returns to the counterclockwise direction, and the stepped portion 2b becomes able to engage with the bent portion 12b. After overrun, the set plate 2 returns to the right a little, and the stepped portion 2b becomes engaged with the bent portion 12b. together, end face 9
The set completion state where b is engaged with the bending 14a is the second state.
As shown in the figure. In addition, the shutter blades 22, 2
3 is in the same state as in FIG.

Next, when a release button (not shown) is pressed down during photographing, a common power switch for a warning circuit (not shown) and an exposure control circuit (not shown) is first closed.

At this time, the warning light receiving window 23c of the shutter blade 23
Since the light-receiving element 24 is exposed to field light, a warning circuit is activated to display conditions such as overexposure, proper exposure, and underexposure.

When the release button is further depressed, the exposure control circuit is activated to excite the electromagnet 11. Therefore, the iron piece 12a is attracted, and the iron piece lever 12 is rotated to the right against the tension of the spring 13, causing the iron piece 12b to bend.
comes off from the stepped portion 2b of the set plate 2. Further, the synchronizer contact piece (A) 18 returns to its original state following the displacement of the bending 12d caused by the right rotation of the iron piece lever 12, and moves away from the synchronizer contact piece (B) 19.

Then, the set plate 2, which has been released from the lock, starts to move to the right due to the tension of the spring 16, and the swing lever 9 pushes the opening/closing lever 14, and the lever 14 is moved into the rack 2a. It is rotated to the right at a constant speed under the action of the meshing flywheel 7 system.

By turning the opening/closing lever 14 to the right, on the one hand, the pin 14c is retracted, and the synchronizing contact (B) 19
is rotated to the left by the tension of the spring 20 and approaches the synchro contact (A) 18. On the other hand, the shutter blades 22 and 23 are connected to the pins 14d and 14e and the long groove 2.
2b and 23b, one of the shutter blades 23 temporarily blocks the light-receiving element 24 from the field light, and then closes the light-receiving window 2 for exposure control.
3d to expose the subject to field light again, and both to open the aperture.

Note that the timing circuit section in the exposure control circuit is placed in an operable state when the light receiving element 24 is once shielded from field light.

FIG. 3 shows a state in which the shutter blades 22 and 23 open the aperture 1a halfway.

After that, due to the operation of the exposure control circuit, the electromagnet 1
1 is demagnetized, the iron lever 12 is rotated to the left by the tension of the spring 13, and the arm 12c pushes the pin 9a to rotate the swinging lever 9 to the right against the tension of the spring 10. Insulating member 12
The synchro contact piece (A) 18 is pushed through e and brought into contact with the synchro contact piece (B) 19. Therefore, when the flash device is set to a ready state, the flash device emits light near its maximum aperture at any given time.

The state when this iron lever 12 rotates to the left is the fourth state.
In the figure, the set plate 2 has been moved to its rightmost position, and the opening/closing lever 14 is shown in the same position as in FIG.

Then, the swing lever 9 is rotated to the right and the end 9b
When the shutter blade 22 and
23 is rapidly closed, and the arm portion 19b is pushed by the pin 14c to close the synchro contact piece (B) 19.
is rotated to the right against the tension of the spring 20 to separate it from the synchro contact piece (A) 18.

This operation returns all the members to the state shown in FIG. 1.

In addition, if the pin 21 is made eccentrically adjustable to change the left rotation amount of the synchronizer contact piece (B) 19, the timing of contact with the synchro contact piece (A) 18 can be set appropriately. .

The basic operation of the electromagnet 11 described above is to be energized to release the shutter, attract and hold the iron lever 12, and to release the iron lever 12 by being demagnetized after a set or controlled time. was excited and attracted the iron piece lever 12, but
If the iron piece lever 12 cannot be held after that due to a low temperature environment or deterioration of the power supply battery, the iron piece lever 12 will be immediately released regardless of the control time.

This state is shown in FIG. 5 (synchronizer contact piece omitted), but the bending 12b of the iron piece lever 12 is temporarily restrained by the protrusion 2c at the stage of rightward movement of the set plate 2, so the iron piece lever 12 is not completely bent. I can't turn left. Therefore, by turning the swing lever 9 slightly to the right, the end face 9
b and the bend 14a of the opening/closing lever 14 is maintained, and the shutter blades 22 and 23 are aligned with the aperture 1.
Do not keep a closed, but open it a little.
Then, as the set plate 2 continues to move to the right and the protrusion 2c passes the bend 12b, the iron lever 12 is completely rotated to the left and performs the same closing operation as described above.

Therefore, as long as the release can be performed, the exposure operation can be performed in a so-called mechanical time corresponding to the shape (length) of the protrusion 2c of the set plate 2.

In the embodiment, one spring serves as both the opening force source and the closing force source for the shutter blade, but separate springs may be provided.

Furthermore, although the setting plate 2 is of the type that moves linearly, it can be changed to one that moves rotationally.

Furthermore, as shown in the embodiment, the warning light receiving window and the exposure control light receiving window for the light receiving element are formed only on one shutter blade.

Conventionally, this type of light-receiving window is formed on both shutter blades, and the aperture of the light-receiving window for exposure control in particular is changed by a combined operation of both shutter blades. Therefore, in order to obtain a predetermined diameter change without increasing the size of the shutter blade, the light receiving window of each shutter blade must be formed near the pivot point of the shutter blade. As a result, since the amount of movement of the light-receiving window portion is small, there is a drawback that a high degree of processing precision is required to form the light-receiving window. On the other hand, if the light-receiving window is moved away from the pivot point of the shutter blade so that the light-receiving window has a large amount of momentum, the shutter blade itself becomes larger.

As in this example, if the light receiving window is formed on only one shutter blade to control the amount of light received, there are fewer restrictions on where the light receiving window is formed relative to the shutter blade, so the light receiving window can be formed without making the shutter blade too large. This makes it possible to increase the momentum of the light-receiving window, and as a result, high processing accuracy is no longer required for forming the light-receiving window.

As described above, the synchro contact mechanism of the programmed electric shutter of the present invention closes the synchro contact by the iron piece member that moves for closing control, and the synchro contact mechanism closes the synchro contact by the movement of the opening/closing member to close the shutter blade. Since the contacts are opened again, a synchronized operation can be stably and reliably obtained corresponding to the maximum opening of each program operation, and erroneous light emission will not occur.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram showing the overall view of the shutter mechanism according to the present invention in a static state, Fig. 2 is an explanatory diagram of the shutter set state, and Fig. 3 is an explanatory diagram of the shutter blade in the middle of operation when it is opened to a certain diameter. , FIG. 4 is an explanatory diagram of a state in the middle of transition to a closing operation, and FIG. 5 is an explanatory diagram of a state in the middle of mechanical time control. 2... Set plate, 9... Rocking lever, 11...
Electromagnet, 12... Iron piece lever, 14... Opening/closing lever, 16... Spring, 18... Synchro contact piece (A), 19... Synchro contact piece (B), 22, 23
...Shaft blade, 23c, 23d...Light receiving window,
24... Light receiving element.

Claims (1)

[Claim for Utility Model Registration] An opening/closing member that reciprocates a set of shutter blades that also serve as aperture blades, and a movement that moves the opening/closing member in the direction of controlling the opening of the shutter blades by the movement attracted by the electromagnet, and moves away from the electromagnet. In the programmed electric shutter, the synchronizing contact is composed of two contact pieces, one of which is moved by the attracted movement of the iron piece member. The iron piece moves away from the other contact piece, and is brought into contact with the other contact piece by the separation movement of the iron piece member, and the other contact piece approaches the one contact piece by the opening movement of the opening/closing member, and the iron piece moves away from the other contact piece. A synchronizing contact mechanism for a programmable electric shutter, characterized in that the contact mechanism is separated from the one contact piece by the closing movement of the shutter.