JPH11326990A - Camera shutter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stably execute the opening operations of shutter blades, in a shutter constituted so that a linkage member is actuated in a direction where it crosses an optical axis, so as to execute the opening/closing operations of the shutter blades, linked with an actuating pin reciprocated with a moving magnet type motor. SOLUTION: The shutter blades 4, 5 and 6 are energized in the opening directions by springs 13, 14 and 15. An annular linkage member 3 is actuated upward by these springs 13, 14 and 15 and downward by the actuating pin 12a integrated to a permanent magnet rotor 11. In the closed state of the shutter, the respective projection parts 4a, 5a and 6a of the shutter blades 4, 5 and 6 are abutted on shafts 1h, 1f and 1g by the magnetic force of the rotor 11. Therefore, the opening operations of the shutter blades 4, 5 and 6 are always executed rapidly from fixed positions, to enable stable exposure control.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera shutter in which a plurality of shutter blades open and close a circular exposure opening by reciprocating operation.

[0002]

2. Description of the Related Art This type of shutter is generally called a lens shutter, and is used for exposure operation.
A plurality of shutter blades open the opening for exposure from the center of the optical axis and then close toward the center of the optical axis. During the operation, it is ideal that the plurality of shutter blades can always maintain a substantially circular opening shape. So, in the old days,
Three or more shutter blades are arranged at equal intervals around the exposure opening, and they are operated by a drive ring that reciprocates around the optical axis.

However, in such a shutter, since the drive ring is arranged in a groove formed over the entire circumference with respect to the shutter base plate surface, the processing cost is increased, and the plane friction resistance is not affected. As a result, extremely large peripheral frictional resistance is generated, and there is naturally a limit to speeding up. For this reason, recently, in order to satisfy the above-mentioned opening shape and to be able to cope with miniaturization and high-speed operation, three or more shutter blades are connected to an operating member called a link member made of a thin plate material. Attention has been paid to a shutter having a configuration in which a link member is reciprocated in a direction crossing the optical axis, and shutter blades are opened and closed.

On the other hand, a coil spring has long been used as a drive source for a shutter blade, but recently, a motor has been used as a drive source from the viewpoint that it is not necessary to set a shutter drive mechanism for each photographing. Things to do have increased. At the beginning, the use of stepping motors attracted attention as a type of motor, but stepping motors are problematic in that they are difficult to miniaturize and are expensive. Attention has been paid to the use of a low-cost and easy-to-minimize moving magnet type motor that reciprocates a (usually two-pole) rotor within a predetermined angle range. I have.

Under such circumstances, a link member connecting three or more shutter blades has been reciprocated in a direction transverse to the optical axis in conjunction with the operation of the moving magnet type motor. Camera shutters have been proposed. However, although the moving magnet type motor has the above-mentioned advantages, the starting performance is inferior to that of the stepping motor, and the time required from the start of energization until a predetermined driving force is obtained is long, and the driving force is high. Has a problem that it is easily influenced by slight variations in Further, the driving force is easily influenced by a change in voltage. For this reason, the present applicant has proposed a configuration for solving those problems in Japanese Patent Application Laid-Open No. H10-96974.

According to the invention described in this publication (hereinafter referred to as a conventional example), the end face of the link member in the opening operation direction (the direction in which the shutter blade is operated to perform the opening operation) is provided with an end face of the motor. Because the spring contacts the pin (operating pin) of the operating member integrated with the rotor and is urged in the opening operating direction by the spring, when the operating pin starts operating in the opening operating direction, the force of the spring is linked. The actuation pin is applied via the end face of the member, and the actuation pin will be actuated earlier than if actuated solely by the driving force of the motor by the pin-slot connection. The force of the spring works effectively in the initial stage of the operation start of the motor, and compensates for the poor startability of the motor. And
The closing operation of the shutter blade is performed by the operation pin pressing the end surface of the link member against the force of the spring.

[0007]

However, according to the above-mentioned conventional example, the closing operation of the shutter blade ends when the link member comes into contact with a stopper provided on the shutter base plate and is stopped. The stopped state of the link member is maintained by the magnetic force of the rotor of the motor until the next photographing. However, the stop state of the shutter blade is not maintained even if the stop state of the link member is maintained. That is, each shutter blade is rotatably attached to a shaft having a fulcrum portion erected on a shutter base plate,
This is because the moving point portion is rotatably attached to the link member, so that the moving point portion can freely move by a tolerance in the attachment portion. Therefore, there is a problem that the posture of each shutter blade at the time of the next photographing varies, and the opening operation is not stable, so-called unevenness occurs.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and an object of the present invention is to form an annular or arcuate shape in conjunction with an operating pin reciprocated by a moving magnet type motor. In a shutter of a type in which three or more shutter blades open and close by the reciprocating operation of the link member in a direction crossing the optical axis, each shutter blade is urged in the opening operation direction. By applying a spring, an equivalent function can be obtained without providing a spring that previously urges the link member in the opening operation direction, and the shutter blade is always stable from a predetermined position at the start of photographing. The object of the present invention is to provide a camera shutter capable of performing an opening operation.

[0009]

In order to achieve the above object, a camera shutter according to the present invention has a fulcrum portion and a moving point portion, and is disposed around an exposure opening at a predetermined interval. The shutter has three or more shutter blades that open and close the exposure opening by reciprocatingly rotating at the fulcrum, and has an interlocking part and is rotatably connected to each of the moving points. A link member that is formed in an annular or arcuate shape so as to surround the exposure opening and reciprocates in a direction crossing the optical axis to cause each shutter blade to open and close, and reciprocates in a predetermined angle range. A reciprocating operation by the moving magnet type motor and the motor, and contacting the end face of the interlocking portion of the link member from the direction crossing the optical axis, and pressing the end face during the operation in one direction, and closing the shutter blades; The operating pin and the respective shutter blades are separately opened and biased in the operating direction so that when the operating pin is operated in the other direction, the link member is operated in a state where the end face of the link member is in contact with the operating pin. A plurality of springs, and a plurality of stoppers each of which comes into contact with each shutter blade at the final stage of the closing operation. When the operation pin is operated in the one direction, each shutter blade comes into contact with each stopper. And the shutter blades are kept in contact with each other even after the power supply to the motor is stopped. In the camera shutter according to the present invention, the number of the stoppers may be smaller than the number of the shutter blades, and only a part of the shutter blades may contact the stoppers in a final stage of the closing operation of the shutter blades. Good. Further, in the camera shutter of the present invention, each of the shutter blades has a hole formed at each fulcrum portion rotatably fitted to each pivot shaft, and each of the shutter blades has a shutter abutment against the stopper. At least one of them
The shutter blades are preferably configured such that the pivots of different shutter blades are the stoppers. Also,
The camera shutter of the present invention is provided with a photoelectric sensor for detecting the opening operation position of the shutter blade,
It is preferable that one of the shutter blades is configured such that a portion whose position is detected by the photoelectric sensor abuts on the stopper. Further, in the camera shutter of the present invention, it is effective to provide a single stopper, and to configure the link member to contact the stopper in the final stage of the closing operation of the shutter blade.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described with reference to two illustrated embodiments. 1 to 4 show a first embodiment of the present invention, and FIG. 1 is a plan view of a blade chamber showing a shutter closed state. FIG. 2 is a rear view of FIG. 1, and FIG. 3 is a plan view of the state where the blade chamber is covered with an auxiliary base plate as viewed from the same direction as in FIG. 1. Both drawings show shutter blades. Omitted. FIG. 4 is a plan view of the blade chamber showing the fully opened state of the shutter. 5 and 6 show a second embodiment of the present invention. FIG. 5 is a plan view of a blade chamber showing a shutter closed state, and FIG. 6 is a blade showing a shutter fully opened state. It is a top view of a room. 2 and 3 are also used in the second embodiment. In each embodiment, the same reference numerals are given to common members and parts.

[First Embodiment] First, the configuration of the first embodiment shown in FIGS. 1 to 4 will be described. The shutter base plate 1 is made of a synthetic resin and has a circular opening 1a centered on the optical axis. A wall 1b is formed along the outer peripheral edge of the shutter base plate 1 so as to project toward the near side in FIG. Although an illustration of the mounting structure is omitted, an auxiliary base plate 2 made of synthetic resin is mounted on the shutter base plate 1 on the near side in FIG. As shown in FIG. 3, the overall shape of the auxiliary base plate 2 has substantially the same planar shape as that of the shutter base plate 1, and a blade chamber is formed between the auxiliary base plate 2 and the shutter base plate 1. Has an opening 2a similar to the opening 1a, but the exposure opening as a shutter is regulated by the opening 1a.

An annular link member 3 is provided in the blade chamber.
And three shutter blades 4, 5, and 6, which are arranged in the order of the link member 3, the shutter blade 4, the shutter blade 5, and the shutter blade 6 from the paper surface toward the near side. . In the assembled state, a part (not shown) provided on the auxiliary base plate 2 pushes the shutter blades 6 lightly toward the shutter base plate 1. The link member 3 has a recess 3a, three overhangs 3b,
3c, 3d and three long holes 3e, 3f, 3g are formed, of which the region where the concave portion 3a is formed is the interlocking portion in the present invention.

An overhang 3 formed on the link member 3
b, 3c and 3d are mounted on shelf-like receiving portions 1c, 1d and 1e formed on the shutter base plate 1, respectively.
Further, the long holes 3e, 3f, 3g are respectively provided in the shutter base plate 1
Are loosely fitted to the shafts 1g, 1f, and 1h, which are provided upright, so that the operation of the link member 3 is not restricted by those shafts. In this embodiment, during operation, the link member 3 slides in surface contact with the shutter base plate 1 only with respect to the receiving portions 1c, 1d, and 1e. , Extremely low frictional resistance,
Although it is designed to operate smoothly, the present invention is not limited to this configuration, and does not prevent the provision of the minimum support surface on the shutter base plate 1 and the auxiliary base plate 2 as necessary. Absent.

Further, the shutter blades 4, 5, and 6 are respectively
These holes are rotatably fitted to the shafts 1f, 1g, and 1h, and the opening and closing operation of the opening 1a can be performed using the shafts 1f, 1g, and 1h as fulcrums. Also,
Protrusions 4a, 5a, 6a are formed at the tips of the shutter blades 4, 5, 6 and spring hooks 4b, 5b, 6b are formed at the base. The spring hook 4b is a hole formed in the shutter blade 4.
Further, each of the shutter blades 4, 5, 6 is connected to a connecting shaft 7,
It is attached to the link member 3 by 8, 9
The connecting shafts 7, 8, and 9 are rivet parts, are inserted from the link member 3 side, and are caulked to the shutter blades 4, 5, and 6, respectively. And the link member 3 and each connecting shaft 7,
8 and 9 are movable, and their connecting shafts 7 and 9 are movable.
Reference numerals 8 and 9 indicate moving points of the shutter blades 4, 5, and 6, respectively.

As shown in FIG. 2, a photo reflector 10 is mounted on the rear surface of the shutter base plate 1. As is well known, the photo reflector 10 is provided with a light emitting unit and a light receiving unit, and light emitted from the light emitting unit enters the blade chamber through a slit 1i formed in the shutter base plate 1,
The light is reflected by a reflection sheet (not shown) attached to the auxiliary base plate 2 and enters the light receiving unit. Further, the protrusion 6a formed at the tip of the shutter blade 6 is
In the initial stage of the opening operation, the photo reflector 1
The optical path of 0 can be cut off.

A motor frame (not shown) is mounted on the rear side of the shutter base plate 1, and a motor chamber for disposing a moving magnet type motor is provided between the motor frame and the shutter base plate 1. Are formed.
Since the configuration of the moving magnet type motor is well known, each drawing shows only the minimum members considered necessary for the description of the present embodiment. The rotor 11 is rotatably supported by the shutter base plate 1 and the motor frame described above.
Actuating pin 1 of actuating member 12 formed integrally therewith
2a penetrates through the window 1j formed in the shutter base plate 1 and faces the blade chamber. In FIG. 1, it is in contact with the end face of the concave portion 3a of the link member 3.

The rotor 11 is made of a permanent magnet (usually two poles), but the operating member 12 and the operating pin 12a are usually made of synthetic resin together with the rotating shaft of the rotor 11. There are many. However, a powder of neodymium, which is a magnetic material, is mixed into a nylon-based resin material, and the rotor 11, the operating member 12, and the operating pin 12a are integrally formed with a mold. In some cases, the magnet is magnetized to become a permanent magnet.

As shown in FIG. 3, the auxiliary base plate 2 is provided with shafts 2b, 2c and 2d outside the blade chamber.
Springs 13, 14, and 15 are wound. One end of the spring 13 is hung on a spring hook 2e provided on the auxiliary base plate 2, and the other end is bent and inserted into the blade chamber from the window 2f and hung on the spring hook 4b of the shutter blade 4. I have. Further, one end of the spring 14 is hung on a spring hook 2g provided on the auxiliary base plate 2, and the other end is bent and inserted into the blade chamber from the window 2h.
Is hooked on the spring hook portion 5b. Further, one end of the spring 15 is hung on a spring hook 2i provided on the auxiliary base plate 2, and the other end is bent and inserted into the blade chamber from the window 2j and hung on the spring hook 6b of the shutter blade 6. I have.

Therefore, each shutter blade 4, 5, 6
In FIG. 1, the springs 13, 14, 15 are urged to rotate in the counterclockwise direction, and thereby the link member 3 is urged to operate upward. In the present embodiment, three stoppers 1k, 1m, and 1n that are in contact with the shutter base plate 1 when the shutter blades 4, 5, and 6 are fully opened are formed.

Next, the operation of this embodiment will be described. FIG. 1 shows a shutter closed state. At this time, the moving magnet type motor is in a non-energized state, but as is well known, the rotor 11
Is provided with a clockwise rotational force. for that reason,
The link member 3 is pushed downward on the end face of the concave portion 3a by the operating pin 12a. On the other hand, shutter blades 4,
The springs 5, 6 are urged by the springs 13, 14, 15 to rotate counterclockwise. Then, the force acts to move the link member 3 upward through the connecting members 7, 8, and 9. However, since the force is smaller than the force pushed by the operation pin 12a,
The link member 3 is pushed down, and the shutter blades 4, 5, 6
Are maintained in contact with the shafts 1h, 1f, 1g.

When the shutter is released in this state, the power switch is first closed and the photo reflector 10 is turned off.
Becomes energized. Thereby, the photoreflector 1
The light emitted from the light-emitting portion 0 into the blade chamber is
The light is reflected by a reflection sheet (not shown) attached to the photo reflector 10 and enters the light receiving portion of the photo reflector 10. After passing through such a preparation state, when the coil of the moving magnet type motor is energized in the forward direction, the permanent magnet of the rotor 11 loses the maintaining force of the closed state, and the rotor 11 is turned off as shown in FIG. At a predetermined angle in the counterclockwise direction. Therefore, the operation pin 12a operates upward.

As described above, in the case of the moving magnet type motor, the operation is initially slow and unstable, but in the case of this embodiment, the springs 13 and 1 are used.
Since the urging forces of the link members 4 and 15 push the link member 3 upward through the shutter blades 4, 5, and 6, the link member 3
Rather than simply following the operation pin 12a, the operation is performed by positively pushing the operation pin 12a. for that reason,
Even if a moving magnet type motor is used, the initial operation of the link member 3, that is, the initial operation of the shutter blades 4, 5, 6 is relatively fast and stable. still,
The upward movement of the link member 3 is performed by the shutter blades 4,
Since the distance between the supporting points 5 and 6 (the positions of the shafts 1f, 1g and 1h) and the moving point (the positions of the connecting shafts 7, 8 and 9) is invariable, strictly, draw an arc. Will be done.

As described above, when the link member 3 and the shutter blades 4, 5, and 6 start operating, the projection 6a of the shutter blade 6 blocks the optical path of the photo reflector 10 before the pinhole state is established. Therefore, the exposure time control circuit is started by the output signal. Thereafter, the shutter blades 4, 5, and 6 bring the opening 1a into a pinhole state and open the opening 1a about the optical axis. After the opening is fully opened, the end faces in the operating direction are moved to the stoppers 1k and 1m, respectively. , 1n and stop. However, the operating member 12 continues to operate slightly thereafter, and comes into contact with a stopper (not shown) and stops. This state is shown in FIG. The stopper of the operating member 12 may be set at the upper end edge of the window 1j, and the operating pin 12a may be brought into contact therewith.

Thereafter, when a predetermined time has elapsed, the coil of the moving magnet type motor is energized in the opposite direction to the above by the output signal from the exposure time control circuit, and the rotor 11 is turned on in FIG. Rotate in the direction. Therefore, the operating pin 12a operates downward to contact the end face of the concave portion 3a of the link member 3, and thereafter, the link member 3 is operated downward against the urging force of the springs 13, 14, 15 and the shutter is operated. The blades 4, 5, and 6 are connected to the shafts 1f and 1 respectively.
Rotate clockwise at g and 1h. Then, after the shutter blades 4, 5, and 6 close the opening 1a, the projections 4a, 5a, and 6a come into contact with the shafts 1h, 1f, and 1g to stop and return to the state of FIG.

After the respective members return to the state shown in FIG. 1, the energization of the coil of the moving magnet type motor is cut off. However, even if the energization is cut off, the rotor 11 is a permanent magnet. The rotation position is maintained by a well-known configuration, and the closed state of the opening 1a is maintained until the next photographing is performed. That is, when the coil is not energized, the magnetic force equilibrium position of the rotor 11 is set to a position further rotated clockwise than the rotation position shown in FIG. Therefore, in the state shown in FIG. 1, even if the coil is not energized, the link member 3
15, the shutter blades 4, 5, and 6 have their projections 4a, 5a, 6a
h, 1f, and 1g.

Therefore, the shutter blades 4, 5, and 6 may rattle within the above-mentioned tolerance range regardless of the vibration when the camera is not in use or the position of the camera prior to photographing. Instead, this state has been maintained. Therefore, the shutter blades 4, 5, and 6 always start opening from this state during photographing, and stable exposure control can be performed. The spring 13,
As described above, the members 14 and 15 serve not only to maintain such a state but also to improve the opening operation characteristics of the shutter blades 4, 5 and 6, so that the link members 3 There is no need to spring.

In this embodiment, the shafts 1h, 1f, and 1g on which the shutter blades 4, 5, and 6 are pivoted are also used as stoppers when the shutter blades 4, 5, and 6 are closed. However, the independent stopper is
Or the auxiliary base plate 2 may be provided separately.
In addition, those stoppers have three shutter blades 4,
It is not necessary to provide the shutter blades in all of the shutter blades 5 and 6, but may be provided only in some of the shutter blades. Further, the protrusion 6a of the shutter blade 6 has a contact portion with the shaft 1g,
Although the position detector is also used as the photoreflector 10, these functions may be performed in different parts. In the case of a shutter without the photoreflector 10, the projection 6 a is in contact with the shutter 6. Dedicated site.

[Second Embodiment] Next, a second embodiment of the present invention will be described with reference to FIGS. 5 and 6.
Is drawn corresponding to FIGS. 1 and 4 described above. The configuration of the present embodiment is different from that of the first embodiment in that
Since only the shape of the shutter blade is different and a stopper for the link member is newly provided, other components and portions are denoted by the same reference numerals as in the first embodiment, and detailed description thereof will be omitted.

In this embodiment, similarly to the first embodiment, three shutter blades 17, 18, and 19 have their holes rotatably fitted to the shafts 1f, 1g, and 1h. The opening and closing operation of the opening 1a can be performed using the shafts 1f, 1g and 1h as fulcrums. The connection with the link member 3 is the same as in the first embodiment. However, a projection 19 a is formed at the tip of the shutter blade 19, but no projection is formed at the tip of the other shutter blades 17, 18. Shutter blade 17,1
At the base of 8, 19, spring hooks 17a, 18a, 19
b are formed and they have springs 13, 14, 15
Is the same as in the first embodiment. Further, a stopper member 1p is formed on the shutter base plate 1.

Next, the operation of this embodiment will be described.
Portions that overlap with the description of the embodiment will be described in a simplified manner. FIG. 5 shows a shutter closed state, in which the motor is in a non-energized state. However, since a rotational force in the clockwise direction is applied to the rotor 11, the link member 3 is pushed downward by the operating pin 12a. ing. On the other hand, shutter blades 17,
The springs 18, 19 are urged by the springs 13, 14, 15 to rotate in the counterclockwise direction. However, since the force is smaller than the force pushed by the operating pin 12a, the link member 3 is pushed down. , Is kept in contact with the stopper 1p. Therefore, the shutter blade 1
7, 18 and 19 are the shafts 1h, 1f,
No contact with 1g.

When the shutter is released, the power switch is first closed and the photo reflector 10 is turned on. Next, when the coil of the moving magnet type motor is energized in the forward direction, the rotor 11 rotates counterclockwise, and the operating pin 12a operates upward. At this time, the starting property of the moving magnet type motor is not so good, but also in the case of the present embodiment, since the urging forces of the springs 13, 14, 15 act to push the link member 3 upward, the shutter blades 17, The initial operation of 18, 19 is relatively fast and stable.

The link member 3 and the shutter blades 17, 18,
19 starts operation, and immediately before the pinhole state,
The projection 19a of the shutter blade 19 is
The optical path of 0 is cut off, and the exposure time control circuit is started. Thereafter, the shutter blades 17, 18, and 19 open the opening 1a, and after fully opening, come into contact with the stoppers 1k, 1m, and 1n and stop. The operating member 12 continues to operate slightly thereafter, abuts against a stopper (not shown), and stops in the state shown in FIG.

Thereafter, the coil of the moving magnet type motor is energized in the reverse direction by the output signal from the exposure time control circuit, and the rotor 11 is rotated clockwise in FIG. Therefore, the operating pin 12a comes into contact with the end face of the concave portion 3a, and the link member 3 is moved to the springs 13, 1
It is operated downward against the urging force of 4,15. And
This operation is performed when the shutter blades 17, 18, 19 are opened.
After a is closed, the link member 3 stops by coming into contact with the stopper 1p, and returns to the state of FIG.

After returning to the state shown in FIG. 5, energization of the coil of the moving magnet type motor is cut off. However, for the reason already described in the first embodiment, this state is maintained until the next photographing. In this embodiment, the shutter blades 17, 18, and 19 do not abut the stopper in this state. However, when the link member 3 is in contact with the stopper 1p, the shutter blades 17, 18, and 19 are applied with counterclockwise rotational forces by the springs 13, 14, and 15 as described above. There is no backlash (play) within the tolerance range, and when taking a picture, the opening operation is always started from this state, and stable exposure control is possible. Also, the springs 13, 14, 1
5 works not only to maintain such a state, but also to improve the opening operation characteristics of the shutter blades 17, 18, and 19, as described above. It is not necessary to apply a spring to the link member 3 as in the above.

In the description of each of the above embodiments, the shutter blade is described as a camera shutter of a type in which the shutter blades are once fully opened and then start the closing operation. Alternatively, if one of the shutter blades is configured to be stopped in the middle of the opening operation, it is possible to provide a camera shutter that also serves as an aperture, and such a configuration is also included in the present invention. It is.

Further, in each of the above embodiments, it is assumed that the link member is annular, but the present invention is not limited to such a shape. For example, FIG.
And a connecting portion with the shutter blade 5 and the shutter blade 6
It is also possible to leave a connection portion with the above and form an arc shape with a gap between them. In this case, the shape is such that the opening 1a is surrounded by about 240 degrees. Further, the number of shutter blades may be four or more. If the number of the link members is four, the link member may have a shape surrounding the opening at about 270 degrees. However, the present invention is not limited to the case where the shutter blades are arranged at equal intervals.

Further, in each of the above embodiments, the spring 1
Although 3, 14, and 15 are mounted outside the blade chamber, the present invention is not particularly limited to such a configuration. In the blade chamber, the shutter base plate 1 or the auxiliary base plate 2 may be mounted. It may be attached to the shutter base plate 1 outdoors. In each embodiment, the operating member 12 is formed integrally with the rotor 11. However, the operating member 12 is mounted on the shutter base plate 1, and the operating member 12 is reciprocated in conjunction with the rotation of the rotor 11. It does not matter.

[0038]

As described above, according to the present invention, an annular or arc-shaped link member disposed so as to surround an opening for exposure is connected to an operating pin reciprocally operated by a moving magnet type motor. By interlocking and reciprocating in the direction across the optical axis,
In a shutter in which at least one shutter blade performs the opening and closing operation, springs for urging in the opening operation direction are applied to the respective shutter blades. There is no rattling, and the shutter blades can always perform a stable opening operation from a predetermined position.
There is an effect that a spring that has been applied to the link member so as to urge it in the opening operation direction becomes unnecessary.

[Brief description of the drawings]

FIG. 1 is a plan view showing a blade chamber of a first embodiment of the present invention, showing a shutter closed state.

FIG. 2 is a rear view of FIG.

FIG. 3 is a plan view showing a state in which the blade chamber is covered by an auxiliary base plate as viewed from the same direction as in FIG. 1;

FIG. 4 is a plan view showing the blade chamber of the first embodiment, showing a shutter fully opened state.

FIG. 5 is a plan view showing a blade chamber according to a second embodiment of the present invention, showing a shutter closed state.

FIG. 6 is a plan view showing the blade chamber of the second embodiment, showing a shutter fully opened state.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Shutter base plate 1a, 2a Opening 1b Wall 1c, 1d, 1e Receiving part 1f, 1g, 1h, 2b, 2c, 2d Axis 1i Slit 1j, 2f, 2h, 2j Window 1k, 1m, 1n, 1p Stopper 2 Auxiliary Base plate 2e, 2g, 2i Spring hook 3 Link member 3a Recess 3b, 3c, 3d Overhang 3e, 3f, 3g Slot 4, 5, 6, 17, 18, 19 Shutter blade 4a, 5a, 6a, 19a Projection 4b, 5b, 6b, 17a, 18a, 19b Spring hook part 7, 8, 9 Connecting shaft 10 Photoreflector 11 Rotor 12 Operating member 12a Operating pin 13, 14, 15 Spring

Claims (5)

[Claims] An opening and closing operation of the exposure opening is performed by reciprocally rotating at the fulcrum at a predetermined interval. Do 3
A plurality of shutter blades, an interlocking portion, and rotatably connected to each of the moving point portions, formed in an annular or arcuate shape so as to surround the exposure opening, and in a direction crossing the optical axis. A link member that causes each shutter blade to perform opening and closing operations by reciprocating to a moving magnet type motor that reciprocates within a predetermined angle range; and a reciprocating operation performed by the motor and an end surface of an interlocking portion of the link member. An operating pin that contacts the direction transverse to the optical axis and presses the end face to close the shutter blades when operating in one direction, and the shutter blades are separately opened and biased in the operating direction to perform the operation. A plurality of springs that are operated in a state where the end surface of the link member is in contact with the operation pin when the pin is operated in the other direction; A plurality of stoppers that abut against each other at the stage, and the operation of the operating pin in the one direction is stopped by each shutter blade abutting on the respective stopper, and even after the power supply to the motor is cut off. A shutter for a camera, wherein each shutter blade maintains its contact state. 2. The method according to claim 1, wherein the number of the stoppers is smaller than the number of the shutter blades, and in a final stage of the closing operation of the shutter blades, only a part of the shutter blades is in contact with one or more stoppers. The camera shutter according to claim 1, wherein 3. Each of the shutter blades has a hole formed in a fulcrum portion rotatably fitted to a respective pivot shaft, and at least one of the shutter blades abutting on the stopper. 2. The blade according to claim 1, wherein said stopper is a pivot shaft of a different shutter blade.
Or the camera shutter according to 2. 4. A photoelectric sensor for detecting an opening operation position of a shutter blade, wherein one of the shutter blades has a portion whose position is detected by the photoelectric sensor abuts on the stopper. The camera shutter according to any one of claims 1 to 3, wherein: 5. The camera shutter according to claim 1, wherein there is only one stopper, and the link member comes into contact with the stopper at the final stage of the closing operation of the shutter blade.