JP2001042386A - Focal plane shutter for camera - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a simplified focal plane shutter for a camera capable of attaining the miniaturization and the reduction of a cost. SOLUTION: Blades 16, 17, 18, 19 and 20 are pivotally supported by arms 14 and 15 pivotally attached to a shutter base plate 1 so that the blades constitute a parallel link mechanism, and the pin 3c of a 1st driving member 3 is connected to the arm 14. When the locked state by the locking part 6a of a locking member 6 is released according to a photographing start signal, the 1st driving member 3 is rotated counterclockwise so as to fully open an aperture 1a. Thereafter, when the locked state by the locking part 7b of a locking member 7 is released according to a photographing finish signal, pin 3b is pushed by the pushing part 4c of a 2nd driving member 4 so as to rotate the 1st driving member 3 clockwise, thus closing the aperture 1a. The pin 3b of the 1st driving member 3 is kept locked by the locking part 5a of a locking member 5 until the member 3 is locked by the locking member 6 at the time of setting.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a focal plane shutter for a camera in which a rectangular opening provided immediately before an image plane is opened and closed during photographing.

[0002]

2. Description of the Related Art An ordinary camera focal plane shutter includes a front blade (group) and a rear blade (group), and is provided immediately before an image forming plane when the camera is not used. The front opening (group) covers the rectangular opening,
At the time of photographing, the front blade (group) and the rear blade (group) are operated in the same direction at predetermined time intervals, and immediately after the photographing is completed, the opening is covered with the rear blade (group). . When setting the shutter, both the leading blade (group) and the trailing blade (group) are operated in the same direction up to their set position. Further, it is known that the focal plane shutter having such a configuration can be employed not only in a camera using a film but also in an electronic camera using an image pickup device such as a CCD (for example, see Japanese Patent Publication No. 3-79912). ).

[0003]

Incidentally, a focal plane shutter has been known as a built-in one in a high-end camera, so that high-speed photographing can be performed with high accuracy, and light leakage even when a high-sensitivity film is used. High performance has been demanded, such as avoiding worry.
Therefore, on the other hand, although miniaturization and cost reduction are required, they are only after high performance has been obtained. It is no exaggeration to say that there is no such thing. However, recently, if the lens can be replaced, higher speed and higher performance are secondary, and it is a fact that there is a demand first to reduce the size and cost.

Further, in the case of an electronic camera using an image pickup device such as a CCD which has recently increased in number, two shutter blades (a shutter of a camera using a conventional film and a shutter described in the above-mentioned publication) are used. Rather than controlling the exposure of the imaging surface with the slit formed by the group, the imaging is performed by electrically controlling the imaging element, and the entire surface of the imaging element is shuttered until the next imaging is performed. Some are covered. Then, in the case of a focal plane shutter employed in such a camera, first, a reduction in size and cost is required.

However, the conventional focal plane shutter for a camera has two shutter blades (group).
Therefore, the number of parts is extremely large and the number of processing steps is increased, so that it is extremely difficult to reduce the cost. In addition, when the opening for regulating the optical path of the subject is fully opened, two shutters are required. Since the space for accommodating the blades (group) must be provided separately, there is a problem that downsizing is extremely difficult.

The present invention has been made to solve such a problem, and an object of the present invention is to make a plurality of arms pivotally attached to a main plate constitute a parallel link mechanism. A simple camera focal point suitable for miniaturization and cost reduction, in which only a predetermined number of blades are attached, one of the arms is moved forward by a shooting start signal, and moved back by a shooting end signal. It is to provide a plain shutter.

[0007]

In order to achieve the above object, a focal plane shutter for a camera according to the present invention comprises:
Two ground plates which are attached to each other at a predetermined interval to form a blade chamber and at least one of which has a rectangular opening for regulating the optical path of subject light at a position immediately before the imaging surface; A plurality of arms having one end pivotally attached to one of the main plates at a side position of the opening, and a predetermined number of blades attached to form a parallel link mechanism with respect to those arms; Drive means for moving one of the arms forward in response to a shooting start signal and returning in response to a shooting end signal, wherein when one of the arms moves forward, the blades fully open the opening and return. In such a case, the opening is closed. Further, in the focal plane shutter according to the present invention, the driving means includes a first driving member for moving one of the arms forward by an urging force of a first spring, and a first driving member for urging the first driving member by an urging force of a second spring. And a second drive member for operating one of the arms in reverse by operating against the urging force of the first spring, and the first drive member is configured such that the second drive member is the second drive member. When set against the urging force of the spring, it is locked by the locking member, and when the locking is released according to the photographing start signal, a preferable configuration in the case of the spring drive type is provided. can get. In this case, when the first driving member is actuated by the second driving member against the urging force of the first spring, the locking member contacts the first driving member during the operation. When the braking is applied to the operation, each driving member can be suitably stopped. Also, the first driving member is released from the locking by the locking member by the setting means during the process of setting the second driving member against the urging force of the second spring, so that the second driving member is released. When the first driving member is locked by the stop member and is released from the locking by the second locking member in response to the photographing start signal, the locking of the first driving member can be surely performed, and the braking can also be performed. It is possible to make a configuration that can be suitably performed. Further, when the first drive member and one of the arms are configured as a single member, the overall configuration can be simplified.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the embodiments shown in FIGS. These drawings are
FIG. 2 is a plan view of the shutter of the embodiment viewed from the subject side in a state where both are incorporated in the camera. However, the right half of the shutter is not particularly important to the present invention,
In addition, since a person skilled in the art can understand according to a well-known shutter configuration, only the left half is shown. FIG. 1 shows a state in which the shutter is closed immediately after the photographing is completed, FIG. 2 shows a state immediately after the set operation is started, and FIG. 3 shows a state in FIG. 2 during the set operation. FIG. 4 shows the over-set state, FIG. 5 shows the set state, and FIG. 6 shows the shutter open state. In each of the drawings, the springs for urging the respective members are not shown in order to make the drawings easier to see.

First, the configuration of this embodiment will be described. The shutter base plate 1 has an opening 1a formed in a substantially central portion of the shutter base plate 1 and having a horizontally long rectangular shape. However, as described above, each drawing shows only about half of the left side of the embodiment, and thus only a part of the opening 1a is shown. On the back side of the shutter base plate 1, auxiliary base plates (not shown) are attached at predetermined intervals, and a blade chamber is formed between the base plates. Further, an opening similar to the opening 1a is also formed in the auxiliary base plate, and the opening is disposed so as to overlap the opening 1a to regulate the optical path frame of the subject light, that is, the image frame of the subject image. I am trying to do it.

The shutter base plate 1 has an opening 1
An arc-shaped long hole 1b and short holes 1c and 1d are formed on the left side of a. Further, the axes 1e, 1f, 1g, 1h, 1i, 1
j, 1k, 1m and pillars 1n, 1p are erected. Among them, the shafts 1e and 1g also protrude to the rear side of the shutter base plate 1. Further, an annular buffer member 2 is attached to the column 1n, and a column 1p is provided with a first
It serves as a stopper for the set member 10.

Next, on the front side of the shutter base plate 1,
The members attached to the shafts will be described in order. First, a first driving member 3 and a second driving member 4 are rotatably attached to the shaft 1e. Among them, the first driving member 3 is smaller than the second driving member 4 in the shutter base plate 1.
And is biased counterclockwise by a spring (not shown). Also, the first driving member 3
Are pins 3b and 3 provided coaxially with the locked portion 3a.
c, and the tip of the pin 3c provided on the back side penetrates the hole 1b of the shutter base plate 1 and faces the blade chamber. On the other hand, the second driving member 4 is urged to rotate clockwise by a spring stronger than the spring urging the first driving member 3. And roller 4
a, a locked portion 4b, and a pushing portion 4c, and the pushing portion 4c pushes the pin 3b of the first drive member 3.

A first locking member 5 for a first driving member is rotatably mounted on the shaft 1f of the shutter base plate 1. The first locking member 5 for the first driving member is urged in the axial direction of the shaft 1f by a leaf spring (not shown) attached to the shaft 1f. The posture at the rotational position is maintained. The first locking member 5 for the first driving member has a locking portion 5 a for locking the pin 3 b of the first driving member 3, and a pushed movement pressed by the pin 3 c of the first driving member 3. Part 5b and two arm parts 5 abutting on the buffer member 2
c, 5d.

A second locking member 6 for a first driving member is rotatably mounted on the shaft 1g of the shutter base plate 1, and is urged to rotate clockwise by a spring (not shown). I have. Then, the first driving member second
The locking member 6 has a locking portion 6a for locking the locked portion 3a of the first driving member 3, a pushed portion 6b, and an engaging portion 6c. Each of them is formed as a bent portion, and the engaging portion 6c is inserted into the hole 1d of the shutter base plate 1.

A second driving member locking member 7 is rotatably mounted on the shaft 1h of the shutter base plate 1, and is urged to rotate clockwise by a spring (not shown). The second driving member locking member 7
, A locking portion 7a for locking the locked portion 4b of the second drive member 4 and a pushed portion 7b are formed by bent portions.
In the state shown in FIG. 1, the position of the second driving member locking member 7 is maintained by the pushed portion 7b contacting the iron piece member of the electromagnet (not shown). . That is, in the state shown in FIG. 1, the electromagnet is in a non-energized state, and the iron piece member is moved to a position where it is separated by the urging force of the spring. 7b is in contact.

A release member 8 is attached to the shaft 1i of the shutter base plate 1.
Is rotatably mounted and urged to rotate clockwise by a spring (not shown).
The release member 8 includes a pushing portion 8a for pushing the pushed portion 6b of the second locking member 6 for the first driving member, and a roller 8b.
, A pin 8c, and a locked portion 8d, of which the pin 8c is provided on the back side and inserted into the hole 1c of the shutter base plate 1. In addition, since the urging force of the spring is stronger than the spring urging the second locking member 6 for the first driving member, in FIG. 1, the release member 8 has a pin 8c having a lower end of the hole 1c. It rotates until it comes into contact with the edge, whereby the pressing portion 8a rotates the second locking member 6 for the first driving member in the counterclockwise direction.

A release member locking member 9 is rotatably mounted on the shaft 1j of the shutter base plate 1, and is urged to rotate counterclockwise by a spring (not shown). The release member locking member 9 includes:
The locking portion 9a for locking the locked portion 8d of the release member 8 and the pushed portion 9b are formed by bent portions. In the state shown in FIG. 1, the release member locking member 9 is configured such that the pushed portion 9 b has an electromagnet (not shown) different from the electromagnet in the description of the second driving member locking member 7. By contacting the iron piece member of the electromagnet), this posture is maintained in the same manner as in the case of the second driving member locking member 7.

A first set member 10 is rotatably mounted on the shaft 1k of the shutter base plate 1, and is urged to rotate counterclockwise by a spring (not shown). Shows a state in which the rotation is prevented by the column 1p. The first set member 10 has a roller 10a operated by a member (not shown) and a pushing portion 10b.

A second set member 11 is rotatably mounted on the shaft 1m of the shutter base plate 1, and is urged to rotate counterclockwise by a spring (not shown). In, the rotation of the roller 11a is prevented by the contact of the roller 11a with the pushing portion 10b. The second set member 11 includes another roller 11b and a pin 11 in addition to the roller 11a.
c and a hole 11d, and in the state of FIG. 1, the roller 11b comes into contact with the roller 4a of the second drive member 4 to prevent the second drive member 4 from rotating clockwise. I have. The pin 11c is for bringing the two iron piece members (not shown) into contact with the respective electromagnets when the second set member 11 is rotated clockwise.

Further, in addition to the first set member 10, a third set member 12 is rotatably mounted on the shaft 1k, and the third set member 12 is provided with a cam-shaped push-pull. A portion 12a, a shaft 12b erected on the surface side,
It has a pin 12c provided on the back side concentrically with the shaft 12b. The pushing portion 12a is a portion that pushes the roller 8b of the release member 8, and the pin 12c is a portion that pushes the arm 5c of the first locking member 5 for the first driving member.

Further, a connection member 13 is attached between the second set member 11 and the third set member 12. The connecting member 13 is rotatably attached to the shaft 12b of the third set member 12, and the hole 11d of the second set member 11 is
To be rotatably fitted to.

Next, the structure of the shutter blades attached to the rear side of the shutter base plate 1 will be described. In the case of this embodiment, the shutter is the same as a normal shutter despite the fact that it is a focal plane shutter. Since no slit is formed at the time of photographing, only one shutter blade is provided. The shutter blade of this embodiment includes two arms 14 and 15 and five blades 16, 17, 18 and 1.
9 and 20. And arm 14,1
5 is a shaft 1 whose one end protrudes into the blade chamber.
e, 1g, rotatably attached. Further, the blades 16, 17, 18, 19, 20 are provided with the arms 14, 15,
Are pivotally supported in order via two connecting shafts, respectively. However, since the configuration of each pivot is well known, detailed description thereof will be omitted. A hole is formed in the arm 14, and the pin 3c of the first drive member 3 is rotatably fitted in the hole.

The focal plane shutter of this embodiment having the above-described configuration can be used for a camera using film without changing a part of the configuration.
The present invention can be applied to a camera using an image pickup device such as a CCD. Therefore, in the following description of the operation of this embodiment, C is relatively likely to be adopted.
The case of a single-lens reflex type electronic camera using a CD will be described.

First, FIG. 1 shows a state immediately after photographing is completed. Therefore, the rectangular opening 1a that regulates the optical path of the subject has five blades 16, 17, 18, 19,
It is closed by 20. Also, this closed state,
The second driving member 4 is rotated clockwise by a spring (not shown) having a large urging force, and the pressing portion 4c pushes the pin 3b of the first driving member 3, and the pin 3c is inserted into the hole 1b. It is maintained by pressing against the lower edge.

In the operation from the state immediately after photographing to the set state, the first set member 10 is rotated clockwise against the urging force of a spring (not shown) by operating the roller 10a. It is done by doing. And the first
Due to the rotation of the set member 10, the pressing portion 10b presses the roller 11a, and rotates the second set member 11 clockwise against the urging force of a spring (not shown).
The rotation of the second set member 11 causes the connection member 1
3, the third set member 12 is rotated clockwise.

The rotation of the second set member 11 causes the roller 11b to press the roller 4a to rotate the second drive member 4 counterclockwise against the urging force of a spring (not shown). . Therefore, the first spring biased to rotate in the counterclockwise direction by a spring (not shown).
In the driving member 3 as well, the pin 3b rotates following the pushing portion 4c, and the arm 3 is rotated counterclockwise by the pin 3c. However, the rotation of the first driving member 3 is stopped immediately after the pin 3c is locked by the locking portion 5a of the first locking member 5 for the first driving member. for that reason,
Since the blades 16, 17, 18, 19, and 20 are only slightly operated, the blades 16, 17, 18, 19, and 20 completely cover the opening 1a in the stopped state. After that, only the second driving member 4 continues to rotate in the counterclockwise direction.

On the other hand, since the third set member 12 is rotating in the clockwise direction in parallel with the clockwise rotation of the second set member 11, the cam-shaped pushing portion 12a is
b, the release member 8 is rotated counterclockwise against the urging force of a spring (not shown). Therefore, the second locking member 6 for the first driving member, which is urged clockwise by a spring (not shown), is rotated by the pushed portion 6b following the pushing portion 8a. 6a is moved within the operation locus of the locked portion 3a of the first drive member 3. And
The rotation of the second locking member 6 for the first driving member is controlled by the engagement portion 6.
The stop is caused by the contact of c with the edge of the hole 1d. The state at that time is shown in FIG.

In the state shown in FIG. 2, the pin 12c provided on the back side of the third set member 12 slightly pushes the lower end edge of the arm 5c of the first locking member 5 for the first drive member. It is also in a state. Therefore, the first locking member 5 for the first driving member
Is slightly rotated clockwise against the frictional resistance given by a leaf spring (not shown), and the arm 5c is separated from the cushioning member 2. The above-described locked state of the first drive member 3 is maintained.

When the setting operation slightly proceeds from this state, the first locking member 5 for the first driving member is further rotated clockwise, so that the locking of the pin 3c is released. Therefore, the first driving member 3 is rotated counterclockwise by the urging force of a spring (not shown), but the rotation is stopped by the locking portion 6a of the second locking member 6 for the first driving member and immediately. Stopped. Therefore, also in this case, the blades 16, 17, 18, 19, and 20 are slightly operated, but in the stopped state, they still completely cover the opening 1a. The state at that time is shown in FIG.

Thereafter, each of the set members 10, 11, 1
2 continues the setting operation, the second set member 11 causes the second drive member 4 to move to the set position by overcharging the spring biasing the second drive member 4 to rotate clockwise. Operate to the overset position beyond. On the other hand, the second set member 11 allows the operation of the well-known holding member in parallel with the pin 11c, and attaches two iron piece members (not shown) to the spring member, which gives them a separating behavior. Operate to the position where it contacts each electromagnet against the power.

As a result, the locking member 7 for the second driving member and the locking member 9 for the releasing member, which have been maintained in the state shown in FIG. 1 by the iron pieces (not shown), are not shown. The second driving member locking member 7 is rotated by the biasing force of the spring, and the second driving member locking member 7 causes the locking portion 7a to face deeply within the operation trajectory of the locked portion 4b of the second driving member 4 to lock the releasing member. The member 9 causes the locking portion 9a to face the operation locus of the locked portion 8d of the release member 8. Then, when the arm 5d of the first locking member 5 for the first drive member comes into contact with the cushioning member 2, the operation of each set member 10, 11, 12 is stopped.
The stopped state is the overset state shown in FIG.

Thereafter, the set member 10 is immediately
The operation of returning to the initial position shown in FIG. Accordingly, the second set member 11 is also rotated counterclockwise by the urging force of the spring (not shown) so that the roller 11a follows the pushing portion 10b, whereby the third set member 11 is connected via the connecting member 13. Although the member 12 is rotated in the counterclockwise direction, the first driving member locking member 5 does not follow the pin 12c of the third set member 12 because the arm portion 5c thereof does not follow the pin 12c of the third set member 12, and the urging force of the leaf spring (not shown) , The position shown in FIG. 4 is maintained.

Further, by the rotation of the second set member 11 in the counterclockwise direction, the second driving member 4 rotates its roller 4a in the clockwise direction following the roller 11b. Immediately, the locked portion 4b is locked by the locking portion 7a of the second driving member locking member 7, and stops. Also,
At the same time, the release member 8 has its roller 8b
The clockwise rotation follows the pressing portion 12a of the setting member 12, but the rotation is caused by the pressing portion 8a pressing the pressed portion 6b of the second locking member 6 for the first driving member. Previously, the locked portion 8d is stopped by the locking portion 9a of the release member locking member 9 and stopped. And each set member 10, 11, 1
The state in which 2 returns to the position of FIG. 1 is the set state of the present embodiment, and that state is shown in FIG. Even if the setting member 11 returns to such an initial position, the above-mentioned well-known holding member holds the iron piece member in a state of being brought into contact with the electromagnet.

Next, when the power switch is closed prior to photographing, various electronic circuits operate, and the circuits related to exposure control enter a standby state. When the release button of the camera is pressed during photographing, the mirror is flipped up on the one hand, and the two electromagnets (not shown) are energized on the other hand. Thereby, after each iron piece member (not shown) is attracted and held by each electromagnet, the hold member retreats out of the locus of the separating operation of the iron piece members. Then, when the mirror enters a stable stop state, the power supply to one of the two electromagnets is cut off,
The iron piece member adsorbed thereby performs a separating operation from the electromagnet, presses the pushed portion 9b of the release member locking member 9 in the state of FIG. 5, and counters the urging force of a spring (not shown). Rotate in the direction.

As a result, the locking of the releasing member locking member 9 by the locking portion 9a is released, and the releasing member 8
Until it abuts against the lower end edge of c, it rotates clockwise by the urging force of a spring (not shown).
Pushes the pushed portion 6b, so that the second
The locking member 6 is rotated counterclockwise against the urging force of a spring (not shown). Therefore, the locked portion 3a is unlocked by the locking portion 6a, and the first driving member 3 rotates counterclockwise by the urging force of a spring (not shown), and
When c rotates the arm 14 in the counterclockwise direction, the blades 16, 17, 18, 19, and 20 are operated upward. Then, the first driving member 3 brings the pin 3b into contact with the pushing portion 4c of the second driving member 4, and the blades 16, 1
FIG. 6 shows a state in which 7, 18, 19, and 20 are stored at positions above the opening 1a and stopped.

As described above, when the opening 1a is fully opened, the exposure control circuit is started with the signal for starting the accumulation of the predetermined electric charge in the CCD as a trigger signal, and the counting of the predetermined control time is started. Then, when the counting of the control time is completed, the power supply to the other electromagnet of the two electromagnets (not shown) is cut off by the output signal. Therefore, an iron piece member (not shown) performs a separating operation from the electromagnet, and pushes the pushed portion 7b to rotate the second driving member locking member 7 counterclockwise.

As a result, the locking portion 7 with respect to the locked portion 4b
a is released, and the second driving member 4 is rotated clockwise by the urging force of a spring (not shown).
Since the pressing portion 4c rotates while pressing the pin 3b, the first
The driving member 3 is also rotated clockwise. Therefore, the arm 14 is also rotated clockwise by the pin 3c, and the five blades 16, 17, 18, 19, and 20 move downward while reducing the overlap between the adjacent blades, and the opening 1a is opened.
Close. When the closing operation is completed, the pin 3c of the first driving member 3 pushes the pushed portion 5b of the first locking member 5 for the first driving member.

As a result, the first locking member 5 for the first driving member is rotated in the counterclockwise direction. The first locking member 5 for the first driving member includes a leaf spring (not shown). Therefore, the rotation of the first drive member 3 and the second drive member 4 is braked by the frictional resistance caused by the bias. The rotation of the driving members 3 and 4 is stopped when the arm 5c of the first locking member 5 for the first driving member comes into contact with the cushioning member 2.

At this time, although the braking is applied by the frictional resistance force of the leaf spring and the shock at the time of stopping is absorbed by the cushioning member 2, the driving members 3,
4 may temporarily open a part of the opening 1a, but at that time, the locking portion 5a of the first locking member 5 for the first driving member already has the bouncing of the pin 3c. Such an inconvenience does not occur because it is within the directional trajectory. In this way, after the opening 1a is closed, the subject image is stored in the storage medium via the image writing device or the like, and the mirror is returned to the observable state by the finder optical system to prepare for the next photographing. become.
This is the state shown in FIG.

Although the above operation has been described with reference to a single-lens reflex camera in which a CCD is arranged on an image-forming surface, it is needless to explain in detail. It can also be used in the case of a reflex camera. However, in that case, it goes without saying that the type is different from the type in which the slit is formed by the front blade (group) and the rear blade (group) as usual. In this embodiment, five blades are pivotally supported by two arms.
The present invention is not limited to the embodiment. However, it is preferable that the number of arms is two, especially when there is one blade.

In the above embodiment, the leaf spring is attached to the rotating shaft 1f of the first locking member 5 for the first driving member.
Although a complicated configuration is employed to ensure that the first driving member 3 can be locked by the first locking member 5 for the first driving member, the first driving member 3 can be reliably locked. If
By applying a biasing force that rotates in the counterclockwise direction to the first locking member 5 for the first driving member by the torsion coil spring,
At the start of the opening operation, in the embodiment, the locking of the first driving member 3 by the locking portion 5a is released by the iron piece member pressing the pushed portion 9b of the locking member 9 for the release member. The configuration becomes much simpler.

In the above embodiment, the first driving member 3 and the arm 14 are formed as separate members.
These may be configured as a single member. That is, the arm 14 is urged by a spring so as to rotate in the counterclockwise direction, pins corresponding to the pins 3b and 3c are provided on the arm 14, and the second drive member 4 is pushed and moved on the front side of the shutter base plate 1. What is necessary is just to comprise so that the part 4c can push the pin and the locking part 5a of the 1st locking member 5 for 1st drive members can lock the pin.

Further, in the above embodiment, the first locking member 5 for the first driving member is configured to brake the operation of the two driving members 3 and 4. The present invention is not limited to the one having such a braking function, and may have only the function of locking the first drive member 3. Further, the shutter of the present invention, as in the embodiment,
The arm is not limited to the one using the spring as the drive source, and the arm may be reciprocated by the reciprocating operation of the motor.

[0043]

As described above, according to the present invention, a predetermined number of blades are attached to a plurality of arms pivotally attached to the main plate so as to constitute a parallel link mechanism, and the arms are turned on by a photographing start signal. Since only one is moved forward and moved backward by the photographing end signal, it is possible to reduce the size and cost, and it is extremely effective as a simple type focal plane shutter for a camera.

[Brief description of the drawings]

FIG. 1 is a plan view showing about half of the left side of a shutter of an embodiment when viewed from a subject side, and shows a closed state immediately after photographing is completed.

FIG. 2 is a plan view of the embodiment shown in the same manner as FIG. 1 and shows a state immediately after a set operation is started.

FIG. 3 is a plan view of the embodiment shown in the same manner as FIGS. 1 and 2, showing a state after FIG. 2 during the setting operation.

FIG. 4 is a plan view of the embodiment shown in the same manner as FIGS. 1 to 3 and shows an overset state.

FIG. 5 is a plan view of the embodiment shown in the same manner as FIGS. 1 to 4 and shows a set state.

FIG. 6 is a plan view of the embodiment shown in the same manner as FIGS. 1 to 5, showing an open state;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Shutter base plate 1a Openings 1b, 1c, 1d, 11d Holes 1e, 1f, 1g, 1h, 1i, 1j, 1k, 1m, 1
2b shaft 2 buffer member 3 first driving member 3a, 4b, 8d locked portion 3b, 3c, 8c, 11c, 12c pin 4 second driving member 4a, 8b, 10a, 11a, 11b roller 4c, 8a, 10b, 12a Pushing portion 5 First locking member for first driving member 5a, 6a, 7a, 9a Locking portion 5b, 6b, 7b, 9b Pushed portion 5c, 5d Arm 6 Second engaging member for first driving member Stop member 6c Engagement part 7 Second drive member locking member 8 Release member 9 Release member locking member 10 First set member 11 Second set member 12 Third set member 13 Connection member 14, 15 Arm 16, 17 , 18,19,20 feather

Claims (5)

[Claims] 1. A rectangular opening for regulating an optical path of subject light at a position immediately before an image forming surface is formed on at least one of them at a predetermined interval to form a blade chamber. Two base plates, a plurality of arms having one end pivotally attached to one of the base plates at a position lateral to the opening, and a predetermined arm attached to the arms so as to constitute a parallel link mechanism. A number of blades, and driving means for moving one of the arms forward by a shooting start signal and moving backward by a shooting end signal, and when one of the arms goes forward, the blade closes the opening. A focal plane shutter for a camera, wherein the shutter is fully opened and the opening is closed when returning. A first drive member for moving one of the arms forward by an urging force of a first spring; and a first driving member for urging the first drive member by an urging force of a second spring. A second driving member that operates against an urging force to move one of the arms back, wherein the first driving member is configured such that the second driving member opposes the urging force of the second spring. It is locked by the locking member when it is set as
2. The focal plane shutter for a camera according to claim 1, wherein the locking is released in response to the photographing start signal. 3. The locking member, when the first driving member is actuated by the second driving member against the urging force of the first spring, causes the first driving member to act on the first driving member during the operation. 3. The focal plane shutter for a camera according to claim 2, wherein the operation is applied to apply a brake to the operation. 4. The method according to claim 1, wherein the first driving member is set in such a manner that the second driving member is set against the urging force of the second spring.
The locking by the locking member is released by the setting means and locked by the second locking member, and the locking by the second locking member is released in response to the photographing start signal. The focal plane shutter for a camera according to claim 2 or 3, wherein: 5. The focal plane shutter for a camera according to claim 2, wherein the first driving member and one of the arms are formed as a single member.