JP4891756B2 - Focal plane shutter for digital camera - Google Patents

Description

  The present invention relates to a focal plane shutter for a digital camera.

  The focal plane shutter for a digital camera has two shutter blades, a front blade and a rear blade, similar to the focal plane shutter for a silver salt film camera. Are sequentially operated in the same direction, and an image pickup surface of an image pickup device such as a CCD is continuously exposed from one side to the other by a slit formed between the two. Further, the leading blade and the trailing blade are connected to the leading blade driving member and the trailing blade driving member, and after the release of the camera, the energization to the leading blade electromagnet and the trailing blade electromagnet is sequentially cut off. These drive members are rotated in order by the urging force of each drive spring, whereby the exposure operation is performed.

  The leading blades and the trailing blades are moved to the set position as the set member is operated from the initial position after the exposure operation is completed and the drive members are rotated against the urging force of the drive springs. It can be operated to. The set member remains in the set position without returning to the initial position until the release button of the camera is pressed at the next shooting, and the release button of the camera is pressed at the next shooting, and each drive member Is securely held by the attraction force of each electromagnet, and then returned to the initial position. Therefore, in the digital camera equipped with this kind of focal plane shutter, in the set state, the imaging surface of the imaging device is covered with the leading blade, so that the finder for observing the subject image is a silver salt film camera. As with, an optical finder is required.

  However, when the setting operation by the setting member as described above is performed, the rear blade is moved to the setting position, but if the front blade is configured to be suppressed at the end position of the exposure operation, the subject light is not emitted in the setting state. Since it can be applied to the image pickup surface of the image pickup device, the subject image formed on the image pickup surface can be displayed on a monitor such as a liquid crystal display device and observed. However, in such a configuration, when the release button is pressed at the time of shooting, first, the leading blade is released and the exposure operation start position is released to temporarily cover the imaging surface of the imaging device. Then, as described above, it is necessary to configure the leading blade and the trailing blade to start the exposure operation in order.

  An example of a focal plane shutter for a digital camera having such a configuration is described in Patent Document 1 below. According to this configuration, the conventional leading blade driving member is composed of the leading blade first driving member connecting the leading blades and the leading blade second driving member rotated by the driving spring during the exposure operation. In the setting operation, the set member suppresses the first driving member for the leading blade in the vicinity of the end position of the exposure operation, and only the second driving member for the leading blade is operated to the setting position. When the release button is pressed at the time of photographing, first, the leading blade electromagnet and the trailing blade electromagnet are energized to hold the leading blade second driving member and trailing blade driving member magnetically, and then the set member is In the return operation, the set member releases the deterrence so that the first drive member for the leading blade and the leading blade can be moved to the exposure start position by the biasing force of the set spring. Yes.

  However, the focal plane shutter described in Patent Document 1 is the first blade driving member for the leading blade immediately after reaching the initial position when the set member returns to the initial position after the release button of the camera is pressed. And the leading blade is moved from the vicinity of the exposure operation end position to the exposure operation start position, so that the first driving member for the leading blade and the leading blade bounce at the exposure operation start position. The stationary state is much later than the setting member returns to the initial position. Therefore, the exposure operation of the leading blade cannot be started immediately after the set member returns to the initial position, and the time from when the release button is pressed until the leading blade starts the exposure operation becomes long. When moving, there is a problem that the possibility of missing a photo opportunity increases.

  Therefore, a special deterrence member is rotatably mounted on the same axis as the set member, and when the set operation is performed, the deterrence member immediately replaces the set member with the first drive member for the leading blade near the exposure operation end position. When the release button is pressed and the set member returns to the initial position, the suppression is released at the initial stage of the return operation, and when the set member returns to the initial position, the leading blade first Patent Document 2 below discloses a digital camera focal plane shutter in which a driving member and a leading blade are in a stationary state after bouncing at an exposure operation start position.

  The configuration of the focal plane shutter described in Patent Document 2 is that the set member and the restraining member are rotatably attached to the same shaft, and the set member has flexibility. The hook part which formed the engaging part in the front-end | tip is provided, and the to-be-engaged part is made to form two to-be-engaged parts in the surrounding surface. When the set member performs the setting operation, the engaging portion of the hook portion engages with one engaged portion of the suppressing member and pulls the suppressing member, and the suppressing member rotates the leading blade first. After coming into contact with the stopper at a position where rotation of the drive member can be suppressed, the hook part is bent and the engagement is released, and only the set member continues to rotate. It stops after returning to its original shape due to its own elasticity. Further, when the set member returns to the initial position, the engagement portion of the hook portion engages with the other engaged portion of the suppression member and rotates so as to push the suppression member. 1 When the restraint of the driving member is released and then the restraining member comes into contact with the stopper, the hook part is bent and the engagement is released, and immediately before reaching the set position, the hook part returns to its original shape by its own elasticity. And then stop.

  By the way, as for the focal plane shutter described in Patent Document 2, as described above, the set member reciprocally rotates the suppression member by the engagement of the engagement portion of the hook portion and the two engagement portions of the suppression portion, The engagement is configured to be released by bending the hook portion. However, it is very difficult to actually mass-produce the focal plane shutter having such a configuration. For example, it can be manufactured so that the elasticity of the hook portion can be obtained uniformly, or so that the friction surface of the engaging portion and the friction surface of the two engaged portions are in a predetermined arrangement relationship. Because it is difficult.

  Therefore, when such a focal plane shutter is mass-produced, even if the restraining member can be rotated by the engagement between the engaging portion and the engaged portion, when the restraining member stops rotating, In some cases, the hook portion does not bend properly and the engagement between the engaging portion and the engaged portion is not smoothly released. Further, even when the engagement between the engagement portion and the engaged portion can be smoothly released when the rotation of the suppression member is stopped, the rotation of the suppression member to a predetermined level when the suppression member is rotated. The engagement between the engaging portion and the engaged portion may be released before contacting the stopper at the position. In particular, when the set member returns to the initial position, the restrained portion of the first drive member for the leading blade is pressed against the restraining portion of the restraining member by the biasing force of the set spring. Before the deterrence is released, the hook portion may be bent, and the engagement between the engaging portion and the engaged portion may be released. Further, as the set member repeats rotating, the hook portion is bent and then does not return to a predetermined original shape, and the engagement between the engaging portion and the engaged portion cannot be suitably performed. However, it may be impossible to reliably rotate the restraining member.

  Therefore, as one method for overcoming these problems, the restraining member is mounted on a different axis from the set member and is always rotated in conjunction with the rotation of the set member. The first drive member for leading blades is configured to be rotated at a different angle, and is reliably restrained by the restraining member in the set state. When the set member returns to the initial position immediately after the release, the restraining member The contact with the restraining member is cut off just before the set member reaches the initial position, and it comes into contact with the second driving member for the leading blade at the exposure operation start position and stops. It is done. The applicant of the present application has filed a patent application (Japanese Patent Application No. 2006-123935) for the invention of the focal plane shutter configured as described above.

Japanese Patent Laid-Open No. 2001-2222059 JP 2003-2222928 A

  However, the above-mentioned focal plane shutter in the patent application is extremely suitable for immediately stopping the first driving member for the leading blade to the exposure operation start position immediately after the release of the camera, and restraining the bounce. Although it is configured, if inconvenience occurs in the electronic circuit that controls the energization of the electromagnet, if some measures are not taken, it is not only necessary to improve the electronic circuit, but also as follows It has been found that this configuration may cause an inconvenient situation.

  That is, as described above, this type of focal plane shutter is provided with a leading blade electromagnet and a trailing blade electromagnet, and when the shutter is released for photographing, the electromagnet is first energized and then set. Is returned to the initial position, and thereafter the energization of the leading blade electromagnet and the trailing blade electromagnet is sequentially cut off. However, in the initial stage of the release, after each electromagnet is energized, the leading blade is moved to the exposure operation start position, and after the set member is returned to the initial position, there is a problem in the energization control circuit for each electromagnet. Thus, energization of each electromagnet is not interrupted at a predetermined timing, and the leading blade and the trailing blade may be left in the exposure operation start position.

  On the other hand, depending on the specifications of the camera, the set operation is automatically started when a predetermined time that exceeds the shooting time has elapsed after the release. Then, when the leading member and the trailing blade remain in the exposure operation start position as described above, if the setting member starts the setting operation as described above, the suppression member is used for the leading blade by the setting member. The pressing member is strongly pressed against the first driving member, and the setting member is stopped without rotating to the setting position. Therefore, not only the interlocking configuration with the set member directly related to the restraining member and the first drive member for the leading blade, but also the interlocking configuration on the drive source side of the set member will cause problems such as destruction and deformation. There is a problem.

  The present invention has been made to solve such problems, and an object thereof is to include a leading blade and a trailing blade, and a driving mechanism of the leading blade is connected to the leading blade. The leading blade first drive member that moves the leading blade to the exposure operation start position by the biasing force of the set spring and the leading blade first drive member through the leading blade first drive member by the biasing force of the leading blade drive spring during the exposure operation. When the setting member is set from the initial position, only the second driving member for the leading blade is applied to the urging force of the driving spring for the leading blade. The first drive member for the leading blade is set in conjunction with the rotation of the set member until the initial stage of the operation in which the release button is pushed and the set member returns to the initial position. Different angle from In a focal plane shutter whose operation to the exposure operation start position is suppressed by a rotation-suppressing member, the first driving member for leading blades is deficient in an electronic circuit that controls the energizing time of the electromagnet for leading blades Thus, it is to provide a focal plane shutter for a digital camera in which the setting operation of the setting member is not started in the state where the exposure operation start position is maintained.

  In order to achieve the above object, a focal plane shutter for a digital camera according to the present invention has an exposure opening and is provided with a first axis, a second axis, a third axis, and a fourth axis upright. A first driving member for a leading blade, which has a shutter base plate, a to-be-suppressed portion and is connected to the leading blade and is rotatably attached to the first shaft; A first blade second drive member that is rotatably attached to one shaft and operates with the first blade drive member by the biasing force of the first blade drive spring during the exposure operation and causes the front blade to perform the exposure operation; A set spring to which a biasing force for operating the first drive member for the leading blade and the leading blade to the exposure operation start position is applied at least when the second driving member for the leading blade is in the set position; Connected to the second shaft for rotation The rear blade drive member that is actuated by the biasing force of the rear blade drive spring during the exposure operation and causes the rear blade to perform the exposure operation, and has a protrusion and is rotatably attached to the third shaft. In the setting operation, the second blade driving member for the leading blade and the driving member for the trailing blade are operated to the respective setting positions against the urging force of each driving spring by operating from the initial position to the setting position. Sometimes it has a set member that returns to the initial position prior to the exposure operation of the leading blade, a restraining portion, and an engaging portion, and is rotatably attached to the fourth shaft. In order to keep the exposure opening fully open when the set member is in the set position by being engaged with the set member and reciprocatingly rotated in conjunction with the set member, Contact And a depressing member that deters rotation of the first driving member for the leading blade due to the urging force of the set spring and releases the deactivation as the set member returns to the initial position, and energization at an initial stage of the release. The leading blade electromagnet which enables the leading blade exposure operation by the leading blade second drive member by cutting off the energization after the returning operation of the set member to the initial position, and energizing in the initial stage of the release The rear blade electromagnet which enables the rear blade exposure operation by the rear blade drive member by cutting off the energization after the start operation of the front blade is started, and is operated by the operation unit at the end of the exposure operation of the front blade. Switch means serving as a signal source for preventing the start of the next set operation of the set member when the electromagnet for the leading blade is not operated after a predetermined time from energization. It is.

  In that case, the switch means may be a signal source for failure display. Moreover, the said suppression member is good to comprise so that the said engaging part may be bifurcated and the said projection part is clamped. The restraining member is biased so as to rotate in one direction by a spring, and when the set member is set, the engaging portion is pushed by the protrusion to resist the biasing force of the spring. The engaging portion may be configured to rotate and follow the protrusion by the biasing force of the spring when the set member is returned.

  Further, the leading blade is composed of a plurality of arms each having one end rotatably attached to the main plate, and at least one blade pivotally supported by the plurality of arms. The set spring has an urging force weaker than that of the leading blade driving spring, and has one end hung on one of the plurality of arms and the other end hung on the base plate. The drive member and the leading blade may be configured to be urged to operate to the exposure operation start position. The set spring has one end hung on the leading blade first drive member and the other end hung on the leading blade second drive member, and only when the restrained portion is restrained by the restraining portion, You may comprise so that the urging | biasing force to the direction which operates the 1st drive member for leading blades and a leading blade to the exposure operation start position may be provided.

  The present invention includes a leading blade and a trailing blade, and a leading blade driving mechanism is connected to the leading blade first driving member connected to the leading blade and the biasing force of the leading blade driving spring during exposure operation. And a first blade driving member that operates the leading blade via the first blade driving member. In the initial stage of the setting operation of the set member, the first blade driving member is the leading blade. The second drive member is operated to follow the second drive member and is mounted on a different axis from the set member, and is restrained by the restraint member that is rotated by the set member in an angle range different from that of the set member. In the focal plane shutter for digital cameras, where the front surface of the element is opened and the subject image can be observed with a liquid crystal display device, etc., after the set member returns to the initial position at the time of release, When the leading electromagnet is not cut off and the leading blade first drive member remains at the exposure operation start position, the setting signal of the setting means is not started by the detection signal of the switch means. In addition to the interlocking configuration with the set member directly related to the member and the first drive member for the leading blade, the interlocking configuration on the drive source side of the set member does not cause problems such as destruction and deformation.

  The embodiment of the present invention will be described with reference to two illustrated examples. 1 to 12 are for explaining the first embodiment, and FIGS. 13 and 14 are for explaining the second embodiment.

  A first embodiment will be described with reference to FIGS. FIG. 1 is a plan view seen from the subject side in a state where it is incorporated in a camera. The outline of the printed wiring board is indicated by a two-dot chain line, so that the state immediately after the exposure operation of the constituent members is completed can be easily understood. It is shown. 2 is an enlarged plan view of a part of FIG. 1, showing a printed wiring board and a switch mechanism attached thereto, and FIG. 3 is a diagram of FIG. FIG. 4 is a cross-sectional view showing the overlapping relationship of the constituent members in an easy-to-understand manner when viewed from the right side of FIGS. 2 and 3. 5 to 11 are plan views showing only main constituent members necessary for explanation of operation among the constituent members shown in FIG. FIG. 5 shows the state immediately after the end of the exposure operation, as in FIG. 3, FIG. 6 shows the initial stage state of the set operation, and FIG. 7 shows the state of FIG. FIG. 8 shows a state where the set operation is further advanced than the state, and FIG. 8 shows a state where the set operation is completed. FIG. 9 shows an initial stage state in which the set member returns from the set position to the initial position prior to the exposure operation when the release button of the camera is pressed. FIG. 10 shows the state of the set member. FIG. 11 shows a state in which the return operation to the initial position has advanced from the state of FIG. 9, and FIG. 11 shows a state immediately before the start of the exposure operation in which the set member has stopped at the initial position. Further, FIG. 12 is a block diagram useful for explaining the operation of this embodiment.

  First, the configuration of the present embodiment will be described mainly with reference to FIGS. 1 to 4, but FIG. 4 is only for the sake of easy understanding of the overlapping relationship of many components shown in FIGS. 1 and 3. Are shown for convenience. In FIG. 1, an opening 1 a for exposure having a rectangular shape is formed in a substantially central portion of the shutter base plate 1. As is well known, an intermediate plate 2 and a cover plate 3 are sequentially attached to the back side of the shutter base plate 1 at a predetermined interval, and a rear blade is interposed between the shutter base plate 1 and the intermediate plate 2. The blade chamber of the leading blade is formed between the intermediate plate 2 and the cover plate 3. The intermediate plate 2 and the cover plate 3 also have openings 2a and 3a having a shape similar to that of the opening 1a. In this embodiment, the shape of the opening 1a regulates the exposure opening. ing. The intermediate plate 2 is not shown in FIGS. 2 to 4, and the cover plate 3 is not shown in FIGS. 2 and 3.

  As clearly shown in FIGS. 1 and 3, two arc-shaped long holes 1 b and 1 c are formed in the left region of the opening 1 a, and a planar shape is formed at the lower end thereof. A well-known rubber cushioning member 4, 5 having a substantially C-shape is attached. The cover plate 3 also has long holes 3b and 3c (see FIG. 4) having substantially the same shape in regions overlapping with the long holes 1b and 1c. The shutter base plate 1 is provided with shafts 1d, 1e, 1f, 1g, 1h, 1i, 1j, and 1k. Among them, the shafts 1d, 1e, 1h, 1i are erected on the surface side of the shutter base plate 1, and the shafts 1j, 1k are erected on the back side of the shutter base plate 1, as can be seen from FIG. The tip is inserted into a hole formed in the cover plate 3. Further, as can be seen from FIG. 4, the shafts 1f and 1g pass through the shutter base plate 1. The shaft portions are provided on both the front surface side and the back surface side of the shutter base plate 1, and the front end of the shaft portion on the back surface side. Is inserted into a hole formed in the cover plate 3. Further, as can be seen from FIG. 4, the shaft 1i is a shaft member having a disk-shaped head, and the tip thereof is press-fitted into a hole formed in the shutter base plate.

  A thin metal support plate 6 and a printed wiring board 7 are attached to the front ends of the shafts 1d and 1e by screws 8 and 9 with the support plate 6 facing the shutter base plate 1 side. Among them, the printed wiring board 7 is attached with two contact piece members 7a and 7b constituting a switch mechanism, as shown in FIG. These contact piece members 7a and 7b have flexibility, and one end thereof is joined to a circuit pattern (not shown) formed on the printed wiring board 7, and the shutter base plate 1 and the printed wiring The other end disposed between the plate 7 is used as a contact portion. As described above, in FIGS. 1 and 3, only the outline of the printed wiring board 7 is indicated by a two-dot chain line.

  Further, the support plate 6 has a shape similar to that of the “mounting substrate” described in JP-A-9-133944, and two ratchet claws 6a and 6b each formed as a bent portion, In addition to the spring hook 6c, the leading blade electromagnet and the trailing blade electromagnet are attached by a plurality of bent portions. Of the two bent portions, the two ratchet claws 6a and 6b have two claw portions 6a-1, 6a-2, 6b at the tip, as shown in FIG. -1 and 6b-2 are formed. The leading blade electromagnet and the trailing blade electromagnet have the same configuration, and are composed of U-shaped iron core members 10 and 11 having two legs and bobbins 14 and 15 around which coils 12 and 13 are wound. It has become. And the iron core members 10 and 11 have the bobbins 14 and 15 fitted to one leg part, and let the front-end | tip of both both leg parts be a magnetic pole part.

  As can be seen from FIG. 4, the shafts 1 f and 1 g each have a portion having a large diameter and a portion having a small diameter at the shaft portion on the surface side of the shutter base plate 1. It is inserted into a hole provided in the printed wiring board 7. The shaft 1f has a first blade first drive member 16 and a first blade second drive member 17 rotatably attached to a large diameter portion formed on the shutter base plate 1 side, and is formed on the support plate 6 side. The ratchet member 18 is rotatably attached to the small diameter portion. On the other hand, the shaft 1g has a rear blade drive member 19 rotatably attached to a portion with a large diameter formed on the shutter base plate 1 side, and a ratchet member 20 on a portion with a small diameter formed on the support plate 6 side. It is attached so that it can rotate.

  The leading blade second drive member 17 includes a cylinder portion 17a, a driven portion 17b, an attachment portion 17c, a pushing portion 17d, and an operation portion provided on the printed wiring board 7 side of the attachment portion 17c. 17e (see FIG. 1 and FIG. 2), and the cylindrical portion 17a is rotatably fitted to the above-mentioned large-diameter portion formed on the shaft 1f. And said contact member 7a is arrange | positioned in the action | operation locus | trajectory of the operation part 17e, and is made to contact the contact member 7b only when pushed by the operation part 17e. Moreover, as shown in FIG. 3 with a part cut away, an iron piece member 21 and a compression spring 22 are accommodated in the mounting portion 17c. The iron piece member 21 has a disc-shaped head portion 21b at one end of the shaft portion 21a. The iron piece portion 21c is attached to the other end of the shaft portion 21a, and the compression spring 22 fitted to the shaft portion 21a. Therefore, the iron piece portion 21c is biased so as to protrude from the mounting portion 17c.

  Further, the first blade first drive member 16 includes a cylindrical portion 16a, a restrained portion 16b, a driven pin 16c, and a drive pin 16d. As can be seen from FIG. The cylinder part 16a is rotatably fitted to the outer periphery of the cylinder part 17a of the second driving member 17 for the leading blade. And the to-be-driven pin 16c is provided in the support plate 6 side, and can be pushed by the pushing part 17d of the 2nd drive member 17 for leading blades. The drive pin 16 d is provided on the shutter base plate 1 side and is inserted into the long hole 1 b of the shutter base plate 1. As shown in FIG. 4, the drive pin 16 d is formed so that the diameter on the base side is slightly larger than the diameter on the tip side, and can come into contact with the buffer member 4. . Further, the tip side portion having a small diameter is connected to the leading blade in the blade chamber as will be described later, and the tip is inserted into the elongated hole 3 b of the cover plate 3.

  As can be seen from FIG. 4, the ratchet member 18 has two ratchet teeth 18a and 18b formed on the outer periphery thereof. The ratchet teeth 18a and 18b are both formed at the same pitch, but the phase is shifted by a half pitch, and the ratchet teeth 18a are engaged with and disengaged from the claw portion 6a-1 of the ratchet claw 6a. The ratchet teeth 18b can be engaged with and disengaged from the claw portion 6a-2 of the ratchet claw 6a. Further, as shown in FIG. 4, a leading blade driving spring 23 is loosely fitted to the cylindrical portion 17 a of the leading blade second driving member 17, and one end of the leading blade second driving member 17 is connected to the leading blade second driving member 17. The other end of the drive member 17 is hung on a spring hook (not shown) of the drive member 17 and the other end of the drive member 17 is hung on a spring hook (not shown) of the ratchet wheel 18. In FIGS. It is energized to rotate to. As is well known, the urging force of the leading blade drive spring 23 can be adjusted by changing the rotational position of the ratchet wheel 18.

  On the other hand, the rear blade drive member 19 that is rotatably attached to the shaft 1g includes a cylindrical portion 19a, an attachment portion 19b, and a drive pin 19c, and also allows the roller 19d to rotate. The cylindrical portion 19a is rotatably fitted to the above-mentioned large-diameter portion formed on the shaft 1g. Further, as shown in FIG. 1 with a part cut away, an iron piece member 24 and a compression spring 25 are accommodated in the mounting portion 19b. And the iron piece member 24 has a disk-shaped head portion 24b at one end of the shaft portion 24a, and the iron piece portion 24c is attached to the other end of the shaft portion 24a, like the iron piece member 21 described above. The compression spring 25 fitted to the shaft portion 24a is urged so that the iron piece portion 24c protrudes from the inside of the attachment portion 19b. The drive pin 19 c is provided on the shutter base plate 1 side and is inserted into the long hole 1 c of the shutter base plate 1. As shown in FIG. 4, the drive pin 19c is also formed so that the diameter on the root side is slightly larger than the diameter on the tip side, similarly to the drive pin 16d. It can come into contact with the member 5. Further, the portion on the front end side having a small diameter is connected to the rear blade in the blade chamber as will be described later, and the front end is inserted into the elongated hole 3 c of the cover plate 3.

  Further, as can be seen from FIG. 3, the ratchet member 20 has the same shape as the ratchet member 18, and two ratchet teeth 20a and 20b are formed on the outer periphery thereof. The ratchet teeth 20a and 20b are both formed at the same pitch, but the phase is shifted by a half pitch, and the ratchet teeth 20a are engaged with and disengaged from the claw portion 6b-1 of the ratchet claw 6b. The ratchet teeth 20b can be engaged with and disengaged from the claw portion 6b-2 of the ratchet claw 6b. Further, as shown in FIG. 4, a rear blade drive spring 26 is loosely fitted to the cylindrical portion 19 a of the rear blade drive member 19, and one end of the rear blade drive member 19 is 1 and 3, the rear blade drive member 19 is urged to rotate in the clockwise direction by hooking it on a spring hook not shown and the other end on a spring hook not shown of the ratchet wheel 20. ing. As is well known, the urging force of the rear blade drive spring 26 can be adjusted by changing the rotational position of the ratchet wheel 20.

  A set member 27 is rotatably attached to the shaft 1h provided upright on the shutter base plate 1. The set member 27 includes a cylindrical portion 27a, pushing portions 27b and 27c, a pushed portion 27d, and a protruding portion 27e, and the cylindrical portion 27a is rotatably fitted to the shaft 1h. Yes. The pushing portion 27b is a portion that pushes the pushed portion 17b of the second driving member 17 for the leading blade, and the pushing portion 27c is a portion that pushes the roller 19d of the driving member 19 for the trailing blade, and The moving part 27d is a part that is pushed by a member on the camera body side (not shown). Further, the protrusion 27e is provided on the surface on the shutter base plate 1 side, and in the case of this embodiment, is formed in a cylindrical shape. Further, a return spring (not shown) is loosely fitted to the cylinder portion 27a, one end of which is hooked to a spring hook portion (not shown) of the set member 27, and the other end is a spring of the support plate 6 described above. 1 and 3, the set member 27 is biased so as to rotate counterclockwise. FIGS. 1 and 3 show that the set member 27 is rotated counterclockwise by the biasing force of such a return spring, and a pin (not shown) provided on the surface of the shutter base plate 1 is connected to the shutter base plate 1. It is in contact with a stopper portion (not shown) provided in FIG. Hereinafter, for the set member 27, this position is referred to as an initial position.

  A restraining member 28 is rotatably attached to the shaft 1 i provided upright on the shutter base plate 1. The restraining member 28 has a restraining portion 28a and an engaging portion 28b. The restraining portion 28a is exposed to the operation locus of the restrained portion 16b of the first driving member 16 for the leading blade, except when the set member 27 is at the initial position and at a position near the initial position. Yes. Further, the engaging portion 28b has a bifurcated shape, and sandwiches the projection portion 27e provided on the set member 27. Therefore, in FIG. 1 and FIG. 3, when the set member 27 rotates in the clockwise direction, the restraining member 28 is rotated counterclockwise by the engaging portion 28 b being pushed by the protrusion 27 e, and then the set member 27. Is rotated counterclockwise, the engaging portion 28b is pushed by the projection 27e and rotated clockwise.

  Next, the configuration of the leading and trailing blades disposed on the back side of the shutter base plate 1 will be described mainly with reference to FIG. In addition to FIG. 5, in FIGS. 6 to 11, the support plate 6, the printed wiring board 7, two electromagnets, two ratchet members 18 and 20 shown in FIGS. 1 and 3, The two iron pieces 21 and 24 and the two compression springs 22 and 25 are not shown. Therefore, first, the front blade is provided on the back side of the shutter base plate 1 with an arm 29 rotatably attached to the shaft 1f, an arm 30 rotatably attached to the shaft 1j, and their tips. It is comprised with three blade | wings 31, 32, 33 pivoted in order toward the part, and the blade | wing 33 is a slit formation blade | wing of a front blade | wing. As is well known, the tip of the drive pin 16 d of the first blade first drive member 16 is fitted in a hole formed in the arm 29. Further, a set spring 34 is fitted to the shaft 1j of the shutter base plate 1, one end thereof is hooked on a spring hooking portion (not shown) provided on the shutter base plate 1, and the other end is hooked on the arm 30. The arm 30 is urged to rotate counterclockwise.

  On the other hand, the rear blade includes an arm 35 that is rotatably attached to the shaft 1g, an arm 36 that is rotatably attached to the shaft 1k, and tip portions thereof on the back side of the shutter base plate 1. The three blades 37, 38, and 39 are pivotally supported in order toward the head, and the blade 39 is a slit forming blade of the rear blade. The tip of the drive pin 19c of the rear blade drive member 19 is fitted in a hole formed in the arm 35 as is well known. Further, a spring 40 is fitted on the shaft 1k of the shutter base plate 1, and one end thereof is hooked on a spring hooking portion (not shown) provided on the shutter base plate 1, and the other end is hooked on the arm 36. 36 is urged to rotate counterclockwise. In addition, in FIG. 4, illustration of the three blades 31 to 33 of the leading blade and the three blades 37 to 39 of the trailing blade is omitted.

  Next, the operation of the present embodiment will be mainly described with reference to FIGS. 5 to 12. Among them, FIGS. 5 to 11 mainly use FIGS. 1 to 4 as described above. A part of the constituent members of the described embodiment is omitted. FIG. 5 shows a stop state immediately after the exposure operation shown in FIGS. At this time, the second driving member 17 for leading blades rotates clockwise with the first driving member 16 for leading blades by the biasing force of the driving spring 23 for leading blades, and the first driving member 16 for leading blades This stop state is maintained by the drive pin 16d coming into contact with the buffer member 4. And the three blades 31 to 33 of the leading blade are overlapped and stored in a position below the opening 1a. At this time, as shown in FIG. 2, the operation portion 17e of the second blade driving member 17 pushes the contact member 7a to contact the contact member 7b. The normal operation determination circuit of the present embodiment shown in FIG. 12 can perform signal processing for a predetermined time by a signal from the CPU when the release button of the camera is pressed during shooting. At this stage, since the predetermined time has elapsed, the ON signals of the contact members 7a and 7b constituting the switch mechanism are ignored.

  On the other hand, the rear blade drive member 19 is rotated in the clockwise direction by the urging force of the rear blade drive spring 26, and this stop state is maintained by the drive pin 19 c contacting the buffer member 5. Therefore, the three blades 37 to 39 of the rear blade are deployed to cover the opening 1a. At this time, the set member 27 is in the initial position, and the restraining member 28 is rotated clockwise by the projection 27e, so that the restraining portion 28a of the restraining member 28 is restrained by the first drive member 16 for the leading blade. This is outside the operating locus of the part 16b. The pushing portion 27b of the set member 27 is separated from the pushed portion 17b of the second driving member 17 for the leading blade, and the pushing portion 27c is separated from the roller 19d of the driving member 19 for the trailing blade. .

  In such an exposure operation end state, when imaging information is transferred to a storage device (not shown), the set motor energization control circuit causes the set motor to move for a predetermined time by a signal from the CPU shown in FIG. The set operation is started immediately. In the case of the present embodiment, when the set motor rotates, a member on the camera body (not shown) that is actuated thereby pushes the driven portion 27d of the set member 27 and returns (not shown). The set member 27 is rotated clockwise against the urging force of the spring. As a result, the restraining member 28 also has its engaging portion 28b pushed by the projection 27e of the set member 27 and rotates counterclockwise, and the restraining portion 28a is restrained by the first drive member 16 for the leading blade. Let's face 16b.

  Thus, when the set member 27 and the restraining member 28 start to rotate, first, the pushing portion 27b of the set member 27 pushes the pushed portion 17b of the second driving member 17 for the leading blade, and the leading blade first 2. The drive member 17 starts to rotate counterclockwise against the biasing force of the leading blade drive spring 23. As a result, the operating portion 17e of the second drive member 17 for the leading blade is moved away from the contact member 7a, and the contact between the two contact members 7a and 7b is eventually released. The off signal at that time is also as described above. Is ignored by the normal operation determination circuit shown in FIG. Further, when the leading blade second driving member 17 rotates counterclockwise in this way, the leading blade first driving member 16 is rotated counterclockwise via the leading blade by the set spring 34. Since the force is applied, the first driving member 16 for the leading blade also starts to rotate counterclockwise with the driven pin 16c following the pressing portion 17d of the second driving member 17 for the leading blade. To do. After that, when the slit forming blade 33 of the leading blade starts to cover the opening 1a, the pushing portion 27c of the setting member 27 starts to press the roller 19d of the trailing blade driving member 19. FIG. 6 shows the state at that time.

  When the set member 27 is still rotated clockwise from the state of FIG. 6, the rear blade drive member 19 is also rotated counterclockwise against the urging force of the rear blade drive spring 26. Accordingly, the drive pin 19c of the rear blade drive member 19 rotates the rear blade arm 35 in the counterclockwise direction, so that the three blades 37 to 39 of the rear blade are moved upward. In this way, the three blades 31 to 33 of the leading blade reduce the overlap between adjacent blades, and the three blades 37 to 39 of the rear blade increase the overlapping of adjacent blades, The state in the middle of moving upward is shown in FIG.

  As can be seen by comparing the state of FIG. 7 with the state of FIG. 6, in the state of FIG. 7, the distance between the restraining portion 28 a of the restraining member 28 and the restrained portion 16 b of the first drive member 16 for the leading blade. Is getting shorter. Therefore, when the suppression member 28 and the first blade first drive member 16 are rotated further counterclockwise than in the state of FIG. 7, the suppression portion 28a and the suppressed portion 16b come into contact with each other. At this time, since the force for rotating the set member 27 is larger than the biasing force of the set spring 34, the depressing portion 28 a resists the biased portion 16 b against the biasing force of the set spring 34 after the contact between the two. Will push. Therefore, after that, the second driving member 17 for the leading blade is rotated counterclockwise by the set member 27 as before, but the first driving member 16 for the leading blade is rotated clockwise. The three blades 31 to 33 of the leading blade are returned to the lower position of the opening 1a while increasing the overlap between the adjacent blades. When the slit forming blade 33 of the leading blade retracts from the opening 1a, the slit forming blade 39 of the rear blade also retracts from the opening 1a, and the opening 1a is fully opened.

  Thus, when the opening 1a is fully opened, the iron pieces 21c and 24c of the iron pieces 21 and 24 attached to the second driving member 17 for the leading blade and the driving member 19 for the trailing blade are moved forward and backward. It contacts the iron core members 10 and 11 of the leading blade electromagnet and the trailing blade electromagnet. Immediately thereafter, the rotation of the set member 27 is stopped, and the rotations of the drive members 16, 17, 19 are stopped. Therefore, when the leading blade second driving member 17 and the trailing blade driving member 19 are stopped, the iron piece portions 21c, 24c of the iron piece members 21, 24 resist the urging force of the compression springs 22, 25. 3 is pushed into the mounting portions 17c and 19b, and the heads 21b and 24b on the opposite side are separated from the mounting portions 17c and 19b. This state is the set completion state shown in FIG. 8, and the set member 27 remains in this set position until the next photographing is performed. If the camera is not turned off when the set operation is completed, the next shooting is in a standby state, and the subject image formed on the image sensor is observed on a monitor such as a liquid crystal display device. It becomes possible to do.

  In the next shooting, when the release button of the camera is pressed, three signals are simultaneously generated from the CPU shown in FIG. As a result, the coil energization control circuit energizes the coils 12 and 13 of the leading blade electromagnet and the trailing blade electromagnet, and attracts and holds the iron piece members 21 and 24 to the iron core members 10 and 11 by electromagnetic force. In addition, the normal operation determination circuit functions only for a predetermined time. Further, the exposure time control circuit starts counting the time corresponding to the subject brightness by the photometry circuit. When the iron pieces 21 and 24 are attracted and held by the iron core members 10 and 11, the set motor energization control circuit next rotates the set motor for a predetermined time by a signal from the CPU, and the camera body side (not shown) The pressing force of the set member 27 on the driven portion 27d of the set member 27 is solved. Therefore, the set member 27 rotates counterclockwise from the state of FIG. 8 by the biasing force of a return spring (not shown) and returns to the initial position.

  In the initial stage of the return operation, the set member 27 has its pushing portion 27b separated from the pushed portion 17b of the second driving member 17 for the leading blade, and the pushing portion 27c of the driving member 19 for the trailing blade. Move away from the roller 19d. Further, since the restraining member 28 is rotated clockwise by the set member 27, the restrained portion 16a of the first blade driving member 16 is restrained by the biasing force of the set spring 34. Is rotated counterclockwise. Thereby, the state when the three blades 31 to 33 of the leading blade begin to cover the opening 1a is shown in FIG.

  In the state shown in FIG. 9, when the set member 27 is separated, the leading blade second drive member 17 and the trailing blade drive member 19 are driven in the respective positions rather than the set position shown in FIG. The urging force of the springs 23 and 26 and the urging force of the compression springs 22 and 25 are slightly rotated in the clockwise direction, and their mounting portions 17c and 19b are brought into contact with the head portions 21b and 24b of the iron piece members 21 and 24, respectively. Yes. The position shown in FIG. 9 is the exposure operation start position for the leading blade second drive member 17 and the trailing blade drive member 19. For this reason, the exposure operation start position is also applied to the rear blade connected to the rear blade drive member 19.

  By the way, as is well known, three blades 37 to 39 are attached to the two arms 35 and 36 so as to be rotatable at a total of six locations. Since these mounting locations are each provided with tolerances, the posture of the slit forming blade 39 at the exposure operation start position slightly changes depending on how the camera is held at the time of shooting. It may become impossible to obtain stably. Therefore, in this embodiment, a biasing force that always rotates counterclockwise is applied to the arm 36 by a spring 40 having a biasing force smaller than that of the trailing blade drive spring 26, and a slit is formed during photographing. The blade 39 can always start the exposure operation from the same posture. Thus, it is well known to provide the spring 40. In this embodiment, the arm 36 is urged to rotate counterclockwise, but is urged to rotate clockwise. However, it is known to have an equivalent effect.

  When the set member 27 further rotates counterclockwise from the position shown in FIG. 9, the restraining member 28 further rotates clockwise, so that the leading blade first drive member 16 has the set spring 34. It further rotates counterclockwise by the biasing force of. FIG. 10 shows a state in which the three blades 31 to 33 of the leading blade cover about 2/3 of the opening 1a. At this time, the driven pin 16c of the first driving member 16 for the leading blade is quite close to the pressing portion 17d of the second driving member 17 for the leading blade. Thereafter, when the three blades 31 to 33 of the leading blades become the rollers that completely cover the opening 1a, the inhibiting member 28 is further rotated in the clockwise direction, so that the inhibiting portion 28a is the first driving for the leading blade. In order to escape from the operation locus of the restrained portion 16b of the member 16, the leading blade first drive member 16 rotates faster than before, and the pushed pin 16c pushes the leading blade second drive member 17. Stops in contact with the portion 17d. Then, a state where the set member 27 returns to the initial position and then stops is shown in FIG. 11, and this position is an exposure operation start position for the first blade first drive member 16 and the front blade.

  By the way, in the present embodiment, as the set member 27 returns to the initial position, the restraining position by the restraining member 28 moves, and the leading blade first drive member 16 rotates counterclockwise. It has become. And the rotational speed of the set member 27 and the suppression member 28 at that time differs. Further, as in the configuration described in Patent Documents 1 and 2, when the suppression of the first blade driving member 16 is released in the vicinity of the exposure operation end position, the driven pin 16c is pushed. The impact at the time of contact with the portion 17d increases, and the second drive member 17 for the leading blade operates slightly, and the compression spring 22 may be temporarily compressed. In such a case, the second driving member 17 for the leading blade strikes the head portion 21b of the iron piece member 21 by the mounting portion 17c and sucks the iron piece portion 21c to the iron core member 10 during the subsequent return operation. The iron core member 10 may be separated from the force.

  However, in the case of the present embodiment, the suppression of the first driving member 16 for the leading blade can be solved by the fact that the driven pin 16c of the first driving member 16 for the leading blade is pushed by the second driving member 17 for the leading blade. This is after approaching the moving part 17d. Therefore, since the rotation angle of the first blade first drive member 16 after the suppression is released is small, the impact force is extremely small even when the driven pin 16c contacts the pressing portion 17d, and the iron core member 10 No influence is exerted on the adsorption state of the iron piece member 21 with respect to. Furthermore, even if the pushed pin 16c contacts the pushing portion 17d, the leading blade first drive member 16 hardly bounces. Therefore, the leading blade first drive member 16 and the leading blade have the set member 27 at the initial stage. When it returns to the position and stops, it is already stationary and the exposure operation can be started anytime.

  In the present embodiment, the three blades 31 to 33 are attached to the two arms 29 and 30 so as to be rotatable at a total of six locations even in the case of the leading blade. Therefore, as in the case of the rear blade described above, depending on how the camera is held during shooting, the posture of the slit forming blade 33 changes at the exposure operation start position shown in FIG. It may become impossible to obtain stably. However, the set spring 34 of the present embodiment has the same function as the spring 40 in addition to the function of operating the first blade first drive member 16 and the front blade to the exposure operation start position as described above. Therefore, even in the case of the leading blade, the slit forming blade 33 can always start the exposure operation from the same posture during photographing.

  As shown in FIG. 11, when the set member 27 stops at the initial position, the CPU shown in FIG. 12 then relays the signal from the exposure time control circuit to the coil energization control circuit, and for the leading blade. The energization to the coil 12 of the electromagnet is cut off. After that, when the counting by the exposure time control circuit corresponding to the subject brightness is completed, the CPU transmits an end signal to the coil energization control circuit to stop energization of the coil 13 of the rear blade electromagnet. Therefore, first, when the energization of the coil 12 of the leading blade electromagnet is cut off, the attractive force of the iron core member 10 with respect to the iron piece member 21 is lost, and the leading blade second driving member 17 moves the leading blade driving spring 23. The urging force is rapidly rotated in the clockwise direction. At that time, the pushing portion 17d pushes the pushed pin 16c, and the leading blade first driving member 16 is turned against the urging force of the set spring 34. Rotate in the direction. Therefore, the three blades 31 to 33 of the leading blade move downward while increasing the overlap between adjacent blades, and open the opening 1 a at the upper edge of the slit forming blade 33.

  On the other hand, when the energization of the coil 13 of the rear blade electromagnet is cut off, the attractive force of the iron core member 11 to the iron piece member 24 is lost, and the rear blade drive member 19 is moved by the biasing force of the rear blade drive spring 26. It is rapidly rotated clockwise. Therefore, the three blades 37 to 39 of the rear blade move downward while reducing the overlap between adjacent blades, and cover the opening 1 a with the lower edge of the slit forming blade 39. Thereafter, in this way, the leading blade and the trailing blade continuously expose the imaging surface of the imaging element from the top to the bottom by the slit formed between the slit forming blades 31 and 39. Become.

  Then, at the final stage of the exposure operation, first, the operation portion 17e of the second blade drive member 17 pushes the contact member 7a of the switch mechanism shown in FIG. Generate a signal. Therefore, the normal operation determination circuit shown in FIG. 12 recognizes that the leading blade exposure operation has been normally performed by the ON signal, and informs the CPU of this. In this way, immediately after the switch mechanism generates the ON signal, the drive pin 16d of the first drive member 16 for the leading blade comes into contact with the buffer member 4, and the two drive members 16 and 17 for the leading blade The operation of the leading blade is stopped. Further, immediately after that, the drive pin 19c of the rear blade drive member 19 comes into contact with the buffer member 5, and the operations of the rear blade drive member 19 and the rear blade are also stopped, as shown in FIGS. It will be in the state shown in. In this state, since a predetermined time has elapsed since the signal from the CPU was sent, signal detection is not performed by the normal operation determination circuit. In this state, the imaging is completed by transferring the imaging information of the subject from the imaging device to the storage device.

  The above explanation of the operation is an explanation when the leading blade and the trailing blade normally perform the exposure operation. Then, next, the point when the exposure operation of the leading blade is not normally performed will be described in a simplified manner with respect to the points overlapping with the above description. First, in the state shown in FIG. 8, after the release button of the camera is pressed, the state until the state shown in FIG. Then, when the set member 27 returns to the initial position and stops as shown in FIG. 11, the CPU shown in FIG. 12 then sends a signal from the exposure time control circuit to the coil energization control circuit. The power supply to the coil 12 of the front blade electromagnet should be cut off, but for some reason, the signal was not transmitted to the coil current control circuit, or the coil current control circuit did not function normally even if it was transmitted. Sometimes, the energization to the coil 12 of the leading blade electromagnet is not cut off.

  In such a case, the leading blade second drive member 17 cannot start operation at a predetermined timing, and remains in the exposure operation start position together with the leading blade first drive member 16 and the leading blade. It is up. On the other hand, when the count end signal from the exposure time control circuit is normally transmitted to the coil energization control circuit via the CPU, and the coil energization control circuit operates normally in response to the signal, the coil 13 of the rear blade electromagnet. The rear blade drive member 19 starts operating normally as described above. However, if for some reason the current to the coil 13 of the rear blade electromagnet is not interrupted, the rear blade The driving member 19 and the rear blade remain at the exposure operation start position.

  When the leading blade second drive member 17 does not start to operate, no ON signal is input from the contact members 7a and 7b within a predetermined time. It is determined that the operation of 17 is abnormal, and an abnormal signal is transmitted to the CPU. In addition, when receiving an abnormal signal from the normal operation determination circuit, the CPU displays an abnormal condition on the error display unit and does not output a signal for rotating the set motor from the set motor energization control circuit. Note that the error display unit may be a part of a monitor screen such as a liquid crystal display device, or may be displayed uniquely by an LED or the like. Also, an abnormal sound may be generated instead of merely displaying an abnormal situation.

  Here, when the leading blade second drive member 17 does not start operation and remains in the exposure operation start position, the set motor is rotated, and the set member 27 starts the set operation from the initial position. Explain what happens. As described above, when the leading blade second drive member 17 remains at the exposure operation start position, the leading blade first drive member 16 also remains at the exposure operation start position. Therefore, the first driving member 16 for the leading blade and the second driving member 17 for the leading blade are in the state shown in FIG. 11, and the set member 27 is also in the state shown in FIG.

  Therefore, from this state, when the set member 27 is rotated clockwise by the member on the camera body side, the suppression member 28 is rotated counterclockwise. Then, the restraining member 28 is only slightly rotated, and the restraining portion 28a comes into contact with the restrained portion 16b of the first blade first drive member 16. Incidentally, as described above, the set member 27 originally rotates the second driving member 17 for the leading blade and the driving member 19 for the trailing blade against the urging force of the respective driving springs 23 and 26 to the set position. Therefore, the rotational force is very large. Therefore, since the restraining member 28 is pressed against the stopped first blade driving member 16 by the strong force, the connecting portion between the set member 27 and the restraining member 28 is particularly damaged. The connection relationship will be crazy. In addition, the same phenomenon occurs in the interlocking configuration from the set motor to the set member 27. Therefore, in this embodiment, the set motor is prevented from rotating.

  In the description of the second embodiment below, the description of the operation when the exposure operation of the leading blade is not normally performed is omitted, but the case of the second embodiment is substantially the same as the case of the present embodiment. The same. In the description of the operation of this embodiment, the switch mechanism including the two contact members 7a and 7b has been described as a signal source for preventing the next set operation from being performed. Needless to say, it can be shared as a signal source for determining the timing of light emission during flash photography.

  Next, Example 2 will be described. FIG. 13 is a plan view showing a state immediately after the end of the exposure operation in the same manner as in FIG. 3 described above, but the second driving member 17 for the leading blade is shown without cutting its mounting portion 17c. . FIG. 14 is a cross-sectional view showing the overlapping relationship of the constituent members in an easy-to-understand manner when viewed from the right side of FIG. The configuration shown in FIG. 2 used in the description of the first embodiment is also used in the description of this embodiment except for the restraining member 28. Moreover, said FIG. 12 used for operation | movement description of Example 1 is used also for operation | movement description of a present Example. Further, in this embodiment, most of the constituent members are the same as those in the first embodiment. Therefore, in FIG.13 and FIG.14, the same code | symbol is attached | subjected to the same member and the same site | part as the case of Example 1. FIG. Therefore, in the following description of the configuration, a configuration different from the first embodiment will be mainly described.

  The restraining member 41 of the present embodiment has a restraining portion 41a and an engaging portion 41b, and is rotatably attached to the shaft 1i of the shutter base plate 1. However, the engaging portion 41b is not formed in a bifurcated shape like the engaging portion 28b of the restraining member 28 in the first embodiment. As can be seen from FIG. 14, in the case of the present embodiment, the shaft 1i is formed longer than in the case of the first embodiment, and the spring 42 is wound around the shaft 1i. Then, the spring 42 is biased to rotate the restraining member 41 clockwise in FIG. 13 by hooking one end thereof to the restraining member 41 and the other end thereof to the shutter base plate 1. The projection 27e of the set member 27 is always brought into contact.

  As can be seen from FIG. 14, in the case of the present embodiment, the cylinder portion 16 a of the first blade first drive member 16 is formed longer than in the case of the first embodiment. Further, the set spring 43 according to the present embodiment is not wound around the shaft 1j like the set spring 34 according to the first embodiment, but is wound around the cylindrical portion 16a. The set spring 43 has one end hung on the leading blade first driving member 16 and the other end hung on the leading blade second driving member 17. From the state shown in FIG. Only when the driven pin 16c of the first driving member 16 and the pressing portion 17d of the second driving member 17 for the leading blade are separated, the first driving member 16 for the leading blade is urged counterclockwise to The second drive member 17 is urged clockwise. In addition, the present embodiment does not include the spring 40 wound around the shaft 1k in the first embodiment. Other configurations are the same as those in the first embodiment.

  Next, the operation of the present embodiment will be described in accordance with the operation description of the first embodiment. However, the points common to the first embodiment will be described as simplified as possible. First, FIG. 13 shows a stop state immediately after the exposure operation ends. At this time, the set member 27 is in the initial position, and the restraining member 41 brings the engaging portion 41b into contact with the protruding portion 27e of the set member 27 by the biasing force of the spring 42, and the restraining portion 41a 1 The driving member 16 is brought out of the operating locus of the restrained portion 16b.

  When the set member 27 starts the setting operation from the initial position, the projection 27e pushes the engaging portion 41b, rotates the restraining member 41 counterclockwise against the biasing force of the spring 42, and the restraining portion 41a It will be made to approach in the operation | movement locus | trajectory of the to-be-inhibited part 16b of the 1st drive member 16 for leading blades. First, the pushing portion 27b of the set member 27 pushes the pushed portion 17b of the second driving member 17 for the leading blade, and the second driving member 17 for the leading blade resists the biasing force of the driving spring 23 for the leading blade. Rotate counterclockwise. At this time, since the set spring 43 is hung between the first driving member 16 for the leading blade and the second driving member 17 for the leading blade, the first driving member 16 for the leading blade is also pushed. The pin 16c rotates counterclockwise following the pushing portion 17d of the second driving member 17 for the leading blade, and moves the three blades 31 to 33 of the leading blade upward. Further, when the leading blade second drive member 17 is rotated counterclockwise, the pressure applied by the operation portion 17e is released, and the contact between the two contact members 7a and 7b is released. In this case, as shown in FIG. Signal detection by the normal operation determination circuit is not performed.

  Thereafter, when the slit forming blade 33 of the leading blade starts to cover the opening 1a, the pushing portion 27c of the setting member 27 starts to press the roller 19d of the trailing blade driving member 19, and the trailing blade driving member 19 is moved to the trailing blade. Since it starts to rotate counterclockwise against the biasing force of the driving spring 26, the three blades 37 to 39 of the rear blade are also moved upward. After that, when the restrained portion 16b of the leading blade first drive member 16 and the restraining portion 41a of the restraining member 41 come into contact with each other, the leading blade second drive member 17 is thereafter counterclockwise by the set member 27. However, the leading blade first driving member 16 is pushed back by the restrained portion 41a of the restraining member 41 with its restrained portion 16b being rotated clockwise. The set spring 43 hung between the drive members 16 and 17 is tensioned. When the opening 1a is fully opened and the iron pieces 21c and 24c of the iron pieces 21 and 24 come into contact with the iron core members 10 and 11, the setting operation is finished.

  When the release button of the camera is pressed at the time of the next shooting, as shown in FIG. 12, the coil energization control circuit energizes the coils 12 and 13 by the signal from the CPU, and the iron pieces 21 and 24 are made of iron. The core members 10 and 11 are sucked and held. On the other hand, the signal from the CPU enables the normal operation determination circuit to detect the signal for a predetermined time, and the exposure time control circuit starts counting the time corresponding to the subject brightness by the photometry circuit. Next, when the set motor energization control circuit rotates the set motor for a predetermined time by a signal from the CPU, the set member 27 starts to return to the initial position by the biasing force of the return spring.

  As a result, the biasing force of the spring 42 causes the restraining member 41 to rotate clockwise while its engaging portion 41b is kept in contact with the protruding portion 27e of the set member 27. 16 is rotated counterclockwise by the biasing force of the set spring 43. After that, when the three blades 31 to 33 of the leading blade are completely covered with the opening 1a, the inhibiting portion 41a of the inhibiting member 41 is actuated by the inhibited portion 16b of the first driving member 16 for the leading blade. In order to escape to the outside, the leading blade first drive member 16 rotates faster than before, and the driven pin 16c comes into contact with the pushing portion 17d of the leading blade second drive member 17 and stops. Immediately thereafter, the set member 27 returns to the initial position and stops.

  Thus, also in the case of the present embodiment, the restraining position by the restraining member 41 moves with the return operation of the set member 27 to the initial position, and the first blade first drive member 16 rotates counterclockwise. I will do it. The deterrence of the restrained portion 16b by the restraining portion 41a is released after the pushed pin 16c of the first driving member 16 for the leading blade approaches the pushing portion 17d of the second driving member 17 for the leading blade. That is. Therefore, even if the deterrence is released and the pushed pin 16c comes into contact with the pushing portion 17d, the impact force is extremely small and does not affect the adsorption state of the iron piece member 21 to the iron core member 10 at all. Further, even if the driven pin 16c comes into contact with the pressing portion 17d, the leading blade first drive member 16 hardly bounces. Therefore, the leading blade first drive member 16 and the leading blade have the set member 27 at the initial stage. When returning to the position, it is already stationary so that the exposure operation can be started at any time.

  When the set member 27 stops at the initial position, the current supply to the coil 12 of the leading blade electromagnet is first cut off, and the power supply to the coil 13 of the trailing blade electromagnet is cut off after a predetermined time. First, when the coil 12 is de-energized, the suction force of the iron core member 10 against the iron piece member 21 is lost, and the leading blade second drive member 17 is rotated clockwise by the biasing force of the leading blade drive spring 23. In this case, the pushing portion 17d pushes the pushed pin 16c to rotate the first blade first drive member 16 in the clockwise direction. Therefore, the three blades 31 to 33 of the leading blade move downward while increasing the overlap between adjacent blades, and open the opening 1 a at the upper edge of the slit forming blade 33. However, in this embodiment, the set spring 43 is not tensioned by this operation.

  On the other hand, when the power supply to the coil 13 is cut off, the suction force of the iron core member 11 against the iron piece member 24 is lost, and the rear blade drive member 19 is rapidly turned clockwise by the urging force of the rear blade drive spring 26. Rotated. Therefore, the three blades 37 to 39 of the rear blade move downward while reducing the overlap between adjacent blades, and cover the opening 1 a with the lower edge of the slit forming blade 39. Thereafter, the imaging surface of the imaging device is continuously exposed from the top to the bottom by the slit formed between the slit forming blades 33 and 39. At the final stage of the exposure operation, first, The operation unit 17e of the second blade driving member 17 pushes the contact member 7a of the switch mechanism shown in FIG. 2 to contact the contact member 7b to generate an ON signal. Therefore, the normal operation determination circuit shown in FIG. 12 recognizes that the leading blade exposure operation has been normally performed by the ON signal, and informs the CPU of this.

  In this way, immediately after the switch mechanism generates the ON signal, the drive pin 16d of the first drive member 16 for the leading blade comes into contact with the buffer member 4, and the two drive members 16 and 17 for the leading blade The operation of the leading blade is stopped. Further, immediately after that, the drive pin 19c of the rear blade drive member 19 comes into contact with the buffer member 5, and the operations of the rear blade drive member 19 and the rear blade are also stopped, and the state shown in FIG. Return. In this state, since a predetermined time has elapsed since the signal was sent from the CPU, signal detection by the normal operation determination circuit is not performed. In this state, the imaging is completed by transferring the imaging information of the subject from the imaging device to the storage device.

  In each of the embodiments described above, a return spring (not shown) is hung on the set member 27, and the set member 27 is set by pushing the driven portion 27d against a member on the camera body side. The return operation to the initial position is performed by a biasing force of a return spring (not shown) as the pressing force of the member on the camera body side is released. The present invention is not limited to the configuration, and the setting operation and the returning operation of the setting member may be forcibly performed by the member on the camera body side without providing the return spring. Further, as in each of the above-described embodiments, the set member 27 may be interlocked via another member provided on the shutter side instead of being directly interlocked with the member on the camera body side. Furthermore, in the case of the above embodiment, each of the leading blade and the trailing blade has three blades. However, the present invention is not limited to such a number, and each one blade is one. It does not matter if the number of both is different.

FIG. 2 is a plan view of the first embodiment viewed from the subject side in a state where it is incorporated in a camera, and the outline of the printed wiring board is indicated by a two-dot chain line to show the state immediately after completion of the exposure operation of the constituent members. Is. It is the top view which expanded a part of FIG. 1, Comprising: A printed wiring board and the switch mechanism attached to it are shown so that it may be understood. FIG. 2 is a plan view in which a part of FIG. 1 is enlarged and shown in the same manner as FIG. FIG. 4 is a cross-sectional view showing the overlapping relationship of constituent members in an easy-to-understand manner when viewed from the right side of FIGS. 2 and 3. It is the top view which showed only the main structural members required for operation | movement description among the structural members shown by FIG. FIG. 6 is a plan view similar to FIG. 5, showing an initial stage state of the set operation. FIG. 6 is a plan view similar to FIG. 5, showing a state in which the set operation has advanced further than the state of FIG. 6. FIG. 6 is a plan view similar to FIG. 5, showing a completed state of the set operation. FIG. 6 is a plan view similar to FIG. 5, showing an initial stage state in which the set member returns from the set position to the initial position prior to the exposure operation when the release button of the camera is pressed. . FIG. 6 is a plan view similar to FIG. 5, showing a state in which the return operation of the set member to the initial position is advanced from the state of FIG. 9. FIG. 6 is a plan view similar to FIG. 5, showing a state immediately before the start of exposure operation in which the set member stops at the initial position. FIG. 3 is a block diagram useful for explaining the operation of the first embodiment. FIG. 10 is a plan view of Example 2 showing a state immediately after the end of the exposure operation in the same manner as in FIG. 3. FIG. 14 is a cross-sectional view showing components in an easy-to-understand manner when viewed from the right side of FIG. 13.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Shutter base plate 1a, 2a, 3a Opening part 1b, 1c, 3b, 3c Long hole 1d, 1e, 1f, 1g, 1h, 1i, 1j, 1k Axis 2 Intermediate | middle plate 3 Cover plate 4, 5 Buffer member 6 Support plate 6a , 6b Ratchet claw 6a-1, 6a-2, 6b-1, 6b-2 Claw part 6c Spring hook part 7 Printed wiring board 7a, 7b Contact member 8, 9 Screw 10, 11 Iron core member 12, 13 Coil 14, 15 Bobbin 16 First blade first drive member 16a, 17a, 19a, 27a Tube portion 16b Blocked portion 16c Pushed pin 16d, 19c Drive pin 17 Second blade second drive member 17b, 27d Driven portion 17c, 19b Mounting portion 17d, 27b, 27c Pushing portion 17e Operation portion 18, 20 Ratchet member 18a, 18b, 20a, 20b Ratchet teeth 19 Rear blade drive member 19 d Roller 21, 24 Iron piece member 21a, 25a Shaft portion 21b, 24b Head portion 21c, 24c Iron piece portion 22, 25 Compression spring 23 Lead blade drive spring 26 Rear blade drive spring 27 Set member 27e Projection portion 28, 41 Suppression member 28a, 41a Suppression part 28b, 41b Engagement part 29, 30, 35, 36 Arm 31, 32, 33, 37, 38, 39 Blade 34, 43 Set spring 40, 42 Spring

Claims (6)

  A shutter base plate that has an opening for exposure and has a first shaft, a second shaft, a third shaft, and a fourth shaft standing upright, and has a restrained portion and is connected to a leading blade. A leading blade first drive member rotatably attached to the first shaft, and an operating portion that is rotatably attached to the first shaft and is attached with a leading blade drive spring during exposure operation. When the leading blade second driving member is operated with the leading blade first driving member by force to cause the leading blade to perform an exposure operation, and at least the leading blade second driving member is at the set position, the leading blade first driving member is at the set position. A set spring to which an urging force for operating the drive member and the leading blade to the exposure operation start position is provided, and is connected to the rear blade and is rotatably attached to the second shaft. It is activated by the urging force of the blade drive spring, and the rear blade is exposed. And a rear blade drive member that has a protrusion and is rotatably attached to the third shaft, and operates from the initial position to the set position during the set operation to move the rear blade second drive member and the rear blade The blade drive member is actuated to the respective set position against the biasing force of each of the drive springs, and when the camera is released, the set member is operated to return to the initial position prior to the exposure operation of the front blade, and the restraining unit. The set member is rotatably attached to the fourth shaft, and the engaging member is engaged with the projection so that the set member is reciprocally rotated in conjunction with the set member. When the is in the set position, in order to keep the exposure opening fully open, the restraining portion comes into contact with the restrained portion and restrains the rotation of the first drive member for the leading blade due to the biasing force of the set spring. The set A depressing member that releases its deterrence when the member returns to the initial position, and a first blade for the first blade by being energized at the initial stage of the release and being de-energized after the set member is returned to the initial position. (2) A front blade electromagnet that enables the exposure operation of the front blade by the drive member, and a rear blade by the rear blade drive member that is energized at the initial stage of the release and is turned off after the exposure operation of the front blade is started. The rear blade electromagnet that enables the exposure operation of the first blade, and the next setting operation of the set member when it is not operated after a predetermined time since it is operated by the operation unit at the end of the exposure operation of the front blade and energizes the front blade electromagnet And a switch means serving as a signal source for preventing the camera from starting, a focal plane shutter for a digital camera.   2. The focal plane shutter for a digital camera according to claim 1, wherein the switch means is also a signal source for failure display.   3. The focal plane shutter for a digital camera according to claim 1, wherein the restraining member has a bifurcated engaging portion and sandwiches the protruding portion. 4.   The restraining member is urged so as to rotate in one direction by a spring, and when the set member is set, the engaging portion is pushed by the projection to rotate against the urging force of the spring. The focal plane for a digital camera according to claim 1 or 2, wherein the engaging portion is rotated following the protrusion by the biasing force of the spring when the set member is returned. Shutter.   The leading blade is composed of a plurality of arms each having one end rotatably attached to the main plate, and at least one blade pivotally supported by the plurality of arms, and the set spring Has a biasing force weaker than that of the leading blade driving spring, one end of which is hung on one of the plurality of arms, and the other end is hung on the base plate, 5. The focal plane shutter for a digital camera according to claim 1, wherein the front blade is urged so as to operate to the exposure operation start position.   One end of the set spring is hung on the first driving member for leading blades, the other end is hooked on the second driving member for leading blades, and the leading blade is only when the restrained portion is restrained by the restraining portion. 5. The focal plane for a digital camera according to claim 1, wherein an urging force is applied in a direction in which the first driving member and the leading blade are actuated to an exposure operation start position. 6. Shutter.

Images