JP2007232963A - Focal plane shutter blade for camera - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide focal plane shutter blades of a camera consisting of two or more blades easy to come close one another and are pivoted on the arm in a manner not to break even deformed by impacts. <P>SOLUTION: Blades 15-17 are, overlapping their holes on the approximately truncated cone shaped protrusions 15c-17c with the holes on the arm 13, secured on the connecting shafts 15a-17a inserted in those holes from the arm 13 side, and can turn relative to the arm 13. The blades 15-17 have protrusions 15c-17c different from one another in protrusion height and are easy to come close one another. Since the lower the blade height is, the smaller are the protruding angles of the protrusions 15c-17c; the higher protrusion has less stress concentrated on the protruding section and is hard to break. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a configuration of one or two shutter blades provided in a camera focal plane shutter.

  In the focal plane shutter for a camera, one shutter blade is arranged in a blade chamber formed between two ground plates and two ground plates are divided by an intermediate plate to constitute two blade chambers. It is known that two shutter blades are separately arranged in these blade chambers. The former focal plane shutter is employed only in digital cameras, while the latter focal plane shutter is employed in both digital cameras and silver salt film cameras.

  Each shutter blade is composed of a plurality of arms having one end pivotally attached to one base plate and the other end being a free end, and a plurality of blades pivotally supported by these arms. In general, each of the pivotal support portions of the blades overlaps the hole provided in the top surface of the substantially frustoconical protrusion formed in the blade and the hole provided in the arm, In addition, the tip of the connecting shaft having a head with a large diameter at one end is inserted from the arm side, and the tip is fixed to the blade in the protruding portion so that the blade can rotate with respect to the arm. It is configured.

  By the way, the shutter blades configured in this way have the same connecting shaft length in each pivotal support portion, and the protrusion height of the protrusion formed on each blade (from the bottom surface of the protrusion portion to the top surface). If the blades pivoted second from the free end side of the arm are suitably brought into close contact with the blade surface of the first blade. become unable. In the same manner, the third and subsequent blades cannot be brought into close contact with the adjacent free end blades and blade surfaces. Therefore, as one method of solving such a problem, the protrusion height of the protrusion portion is increased in order from the blade pivoted on the most free end side of the arm as follows. This is disclosed in FIG. 2 of Patent Document 1.

Japanese Patent Publication No. 7-3535

  In the shutter blade disclosed in FIG. 2 of Patent Document 1, as described above, the protruding height of the protruding portion increases in order from the blade pivoted on the most free end side of the arm. Therefore, the blade surfaces between adjacent blades can be suitably in close contact with each other. However, since the protruding angle of the protruding portion from each blade surface is the same, the protruding height of the protruding portion increases as the blade is pivoted away from the free end of the arm, and the blade deforms. When this is done, much stress will be applied to the protruding position from the blade surface. Therefore, when the blades are deformed by a large impact at the end of the exposure running, there is a problem that stress concentrates on the protruding position and the blades may be destroyed.

  The present invention has been made to solve such problems, and the object of the present invention is to increase the protruding height of the protruding portion in order from the blade pivoted on the most free end side of the arm. Even if the blade is configured to become higher, even if the blade is deformed by a large impact generated at the end of exposure running, the stress concentration on the protruding position from the blade surface is alleviated and the blade is destroyed. It is an object of the present invention to provide a shutter blade for a focal plane shutter for a camera that does not stray.

  In order to achieve the above object, the shutter blade for a focal plane shutter according to the present invention has two arms each having one end rotatably attached to each shaft provided on the base plate and the other end being a free end. And a plurality of blades pivotally supported in order in the length direction of the two arms with respect to both of the two arms, and each pivotal support portion of the arm and the blade is substantially disposed on the blade. A connecting shaft having a hole provided on the top surface of the protruding portion formed in a truncated cone shape and a hole provided in the arm, and having a head having a large diameter at one end. The tip is inserted from the arm side, and the tip is fixed to the blade in the protrusion, so that the blade can be rotated with respect to the arm, and the protrusion is ,in front The shutter blade is formed such that the protruding portion of the blade pivoted at a position away from the free end has a higher protruding height from the blade surface, and the protruding portion is separated from the free end. The protruding portion of the blade pivoted at the position is formed so that the protruding angle becomes smaller. In that case, when the protruding portion is formed in a curved surface in the vicinity of the protruding position from the blade surface, the shutter blade becomes a more robust shutter blade.

  In order to achieve the above object, the shutter blades for focal plane shutters of the present invention are attached so that one end of each of the shutter blades is rotatable with respect to each shaft provided on the base plate, and the other end is a free end. Each of the two arms and a plurality of blades pivotally supported in order in the length direction of the two arms, and each pivot portion of the arms and the blades includes the blades. A hole provided in the top surface of the protruding portion formed in a substantially truncated cone shape is overlapped with a hole provided in the arm, and each of the holes has a head having a large diameter at one end. The tip of the connecting shaft is inserted from the side of the arm, and the tip of the connecting shaft is fixed to the blade in the protruding portion, so that the blade can be rotated with respect to the arm, and the protrusion Part The shutter blade is formed such that the protruding portion of the blade pivoted at a position away from the free end has a higher protruding height from the blade surface, and the protruding portion is spaced from the blade surface. The vicinity of the protruding position is formed on a curved surface.

  Even if the shutter blade of the invention according to claim 1 is configured so that the protrusion height of the protrusion portion increases in order from the blade pivotally supported on the most free end side of the arm, the protrusion portion is Since the blades pivoted farther away from the free end are formed so that the protrusion angle becomes smaller, the stress concentration on the protrusion position from the blade surface due to a large impact generated at the end of exposure running, etc. Is alleviated and the blades are not destroyed. Further, if the vicinity of the protruding position from the blade surface is formed into a curved surface, the stress concentration can be further reduced, and a robust shutter blade can be obtained. Further, the shutter blade of the invention according to claim 3 may be configured such that the protruding height of the protruding portion increases in order from the blade pivoted on the most free end side of the arm. Since the vicinity of the protruding position from the surface is a curved surface, even if all the protruding angles are the same, the stress concentration on the protruding position from the blade surface compared to the case where it is not formed to be a curved surface Is alleviated and the blades are not destroyed.

  Embodiments of the present invention will be described with reference to three illustrated examples. FIGS. 1 to 5 are for explaining the first embodiment, and FIG. 6 is for explaining the second embodiment. FIG. 7 is for explaining the third embodiment. The shutter blade according to the present invention can be applied to a focal plane shutter having two shutter blades, which are referred to as a leading blade and a rear blade, and a focal plane shutter having a single shutter blade. However, the first embodiment is applied to a focal plane shutter having two of them. Further, the focal plane shutter provided with two shutter blades can be used for both a silver salt film camera and a digital camera, but the first embodiment will be described on the assumption that it is used for a digital camera. .

  Embodiment 1 will be described with reference to FIGS. 1 to 5. FIG. 1 is a plan view of the state immediately after the exposure operation is finished as viewed from the photographing lens side, and FIG. 2 is a main portion of the embodiment. FIG. 3 to 5 are plan views as seen in FIG. 1, FIG. 3 shows a set state (photographing standby state), and FIG. 4 shows an exposure operation after release. FIG. 5 shows a state immediately before the start, and FIG. 5 shows a fully open state of the opening for the photographing optical path.

  First, the configuration of this embodiment will be described with reference to FIGS. As shown in FIG. 1, the shutter base plate 1 has an opening 1a for a photographing optical path in which a rectangle is horizontally long at a substantially central portion thereof. In FIG. 1, an auxiliary ground plate 2 having substantially the same outer shape as the shutter base plate 1 is arranged on the back side of the shutter base plate 1, that is, on the imaging device side, as shown in a partially broken view. It is attached to the shutter base plate 1 by no means. The auxiliary base plate 2 also has an opening 2a having the same shape at a position overlapping the opening 1a of the shutter base plate 1. Further, the shutter base plate 1 and the auxiliary base plate 2 are partitioned by an intermediate plate 3 attached to the shutter base plate 1, and a blade chamber of a leading blade is formed between the shutter base plate 1 and the intermediate plate 3. A blade chamber for the trailing blades is formed between the intermediate plate 3 and the intermediate plate 3. The intermediate plate 3 is also formed with an opening 3 a having the same shape as the opening 1 a at a position overlapping the opening 1 a of the shutter base plate 1.

  In FIG. 1, two arc-shaped elongated holes 1b and 1c are formed in the left region of the opening 1a, and the lower end thereof is made of rubber and has a C-shaped planar shape. The known buffer members 4 and 5 are attached. Further, shafts 1d, 1e, and 1f are erected on the surface of the shutter base plate 1 on the photographing lens side, and shafts 1g, 1h, 1i, and 1j are erected on the surface of the blade chamber side. Of these, the shaft 1d and the shaft 1g, and the shaft 1e and the shaft 1i are arranged concentrically. Further, as is well known, a support plate (not shown) is attached to the distal ends of the shafts 1d, 1e, and 1f so as to be parallel to the shutter base plate 1, and the front blade is disposed on the shutter base plate 1 side. The electromagnet for the rear and the electromagnet for the rear blade are attached. In FIG. 1, only the iron core members 6 and 7 of these electromagnets are indicated by a two-dot chain line.

  A synthetic resin front blade drive member 8 is rotatably attached to the shaft 1d of the shutter base plate 1 and is urged to rotate clockwise by a well-known front blade drive spring (not shown). Has been. The leading blade driving member 8 has a driven portion 8a, a driving pin 8b, and a mounting portion 8c. The driving pin 8b passes through the long hole 1b of the shutter base plate 1 and has a blade. It protrudes into the room. In addition, the iron piece member 9 is attached to the attachment portion 8c, and this iron piece member 9 is attached to the iron core member 6 of the electromagnet for the leading blade as described in JP-A-2002-55379. It is adsorbed. Further, the iron piece member 9 is urged so as to move toward the iron core member 6 by a spring provided in the mounting portion 8c, but in FIG. The movement of the portion is prevented by contacting the mounting portion 8c.

  A synthetic resin rear blade drive member 10 is rotatably attached to the shaft 1e of the shutter base plate 1 and is urged to rotate clockwise by a known rear blade drive spring (not shown). Has been. The rear blade drive member 10 includes a roller 10a, a drive pin 10b, and a mounting portion 10c. The drive pin 10b passes through the long hole 1c of the shutter base plate 1 and enters the blade chamber. Stick out. The mounting portion 10c has a shape similar to that of the mounting portion 8c, and an iron piece member 11 attracted to the iron core member 7 of the rear blade electromagnet includes a spring (not shown). Although attached by interposing, the attachment structure is the same as the case of the iron piece member 9.

  A synthetic resin set member 12 is rotatably attached to the shaft 1 f of the shutter base plate 1. This set member 12 has pushing parts 12a and 12b and a pushed part 12c. The pushing part 12a pushes the pushed part 8a of the leading blade drive member 8 and pushes the pushing part 12b. Is configured to push the roller 10a of the driving member 10 for the rear blade. The set member 12 is urged to rotate counterclockwise by a return spring (not shown), but FIG. 1 is prevented from rotating by a stopper (not shown) and is set to the initial position. It shows a state in which it is stopped.

  Next, the configuration of the leading blade and the trailing blade will be described. As described above, the leading blade is disposed between the shutter base plate 1 and the intermediate plate 3 and freely has two arms 13 and 14 each having one end rotatably attached to the shafts 1g and 1h. The blades 15, 16, and 17 are pivotally supported in order toward the other end that is the end, and the blade 17 that is pivotally supported on the most free end side is the slit-forming blade. As is well known, the drive pin 8 b of the leading blade drive member 8 is fitted in the hole formed in the arm 13. Then, as can be seen from FIG. 2, the leading blades are arranged so that the arms 13 and 14 are closest to the shutter base plate 1 side, and the blades 17, 16 and 15 are arranged in this order toward the intermediate plate 3 side. Has been. As can be seen from FIG. 1, the blades 15, 16, and 17 have two connecting shafts 15 a, 15 b, 16 a, 16 b, 17 a, and 17 b with respect to both the arms 13 and 14 at one end in the length direction. The details of the pivot structure will be described later.

  On the other hand, the rear blade is disposed between the auxiliary base plate 2 and the intermediate plate 3, and has two arms 18, 19 each having one end rotatably attached to the shafts 1 i, 1 j and a free end. The blade 22 is composed of three blades 20, 21, and 22 that are pivotally supported in order toward a certain other end, and the blade 22 that is pivotally supported at the most free end side is a slit forming blade. Further, the drive pin 10 b of the rear blade drive member 10 is fitted in the hole formed in the arm 18. The rear blade group is arranged so that the arms 18 and 19 are closest to the auxiliary base plate 2 side and the blades 22, 21, and 20 are arranged in this order toward the intermediate plate 3 side. As can be seen from FIG. 1, the blades 20, 21, and 22 are pivotally supported at both ends of the longitudinal direction via two connecting shafts with respect to both the arms 18 and 19. Reference numerals for the connecting shaft are omitted.

  Here, the pivotal support structure of the shutter blade of this embodiment will be described in more detail. In the case of this embodiment, the structure of the front blade and the structure of the rear blade are exactly the same, and the rear blade is It is only arranged with the leading blade turned inside out. Therefore, in order to avoid duplication, description is abbreviate | omitted about the detailed pivot structure of a rear blade. Further, in the leading blade, the two pivot structures for each blade relative to the arms 13 and 14 are the same, but the three blades 15, 16 and 17 are different from each other. Therefore, in order to clarify the different points, FIG. 2 shows only the pivotal configuration of the blades 15, 16, and 17 with respect to the arm 13. explain.

  First, the arm 13 and the blades 15, 16, and 17 are provided with holes provided on the top surfaces of the substantially frustoconical protrusions 15 c, 16 c, and 17 c formed in the blades 15, 16, and 17, as in the conventional art. The ends of the connecting shafts 15a, 16a, 17a having large diameter heads are inserted into these holes from the arm 13 side, and the protruding portions 15c, In 16c and 17c, the front ends thereof are fixed to the blades 15, 16, and 17 by caulking so that the blades 15, 16, and 17 can rotate with respect to the arm 13. The connecting shafts 15a, 16a, and 17a have the same shape and size, and are common parts.

  The difference between the three pivot structures shown in the drawings is in the shape of the protruding portions 15c, 16c, and 17c having a substantially truncated cone shape formed on the blades 15, 16, and 17, respectively. That is, each protruding portion 15c, 16c, 17c has a substantially truncated cone shape, but the same is only the size of the top surface on which the hole is formed. The protrusion height of the protrusion 16c is substantially higher than the protrusion 17c on the most free end side of the arm 13 by the thickness of one blade, and the protrusion 15c is higher than the protrusion 16c. Is higher in the same way. For this reason, the blades 15 to 17 can always be in close contact with each other.

Further, the difference in shape between the protruding portions 15c, 16c, and 17c, which is a unique configuration of the present embodiment, is that the protruding angle θ _{1 at} the protruding position of the blades 15, 16, and 17 from the blade surface. , Θ ₂ , θ ₃ are smaller in the protruding portion 16c than in the protruding portion 17c, and smaller in the protruding portion 15c than in the protruding portion 16c (θ ₁ <θ ₂ <θ ₃ ). Therefore, in addition to the above-described difference in the protrusion height, the circular diameter formed at the protrusion position, that is, the diameters d ₁ , d ₂ , and d ₃ of the bottom of the frustoconical shape is larger in the protrusion 16c than in the protrusion 17c. The protruding portion 15c is extremely larger than the protruding portion 16c (d ₁ > d ₂ > d ₃ ). Therefore, the distance between the connecting shafts increases from the free end of the arm 13 toward the side attached to the main plate 1.

  Next, the operation of this embodiment will be described. FIG. 1 shows a state immediately after the end of the exposure operation. Therefore, in this state, the three blades 15 to 17 of the leading blade are in a superimposed state in which the overlapping amount between adjacent blades is maximized, and are stored in a position below the opening 1a. On the other hand, the three blades 20 to 22 of the rear blades are in a developed state in which the amount of overlap between adjacent blades is minimized, and cover the opening 1a. When photographing is completed in such a state, the set member 12 is pushed by the member on the camera body side by the pushed portion 11c, and is rotated clockwise against a biasing force of a return spring (not shown).

  As a result, the set member 12 first resists the urging force of the front blade drive spring (not shown) by the pushing portion 12a pushing the driven portion 8a of the front blade drive member 8. The blade driving member 8 starts to rotate counterclockwise. Immediately after that, the pushing portion 12b pushes the roller 10a of the trailing blade driving member 10, thereby resisting the biasing force of the trailing blade driving spring (not shown). Start rotating counterclockwise. Therefore, the three blades 15 to 17 of the leading blade operate upward while reducing the overlap between adjacent blades, and the three blades 20 to 22 of the rear blade increase the overlap between adjacent blades. While moving upwards.

  Then, the three blades 15 to 17 of the leading blade are in the unfolded state to cover the opening 1a, and the three blades 20 to 22 of the trailing blade are superposed and stored in the upper position of the opening 1a. If it will be in a state, the iron piece members 9 and 11 of each drive member 8 and 10 will contact the iron core members 6 and 7 of each electromagnet, and immediately after that, rotation of the set member 12 will be stopped and a set operation will be complete | finished. FIG. 3 shows the set state, that is, the standby state for the next photographing. The drive members 8 and 10 are slightly rotated even after the iron piece members 9 and 11 contact the iron core members 6 and 7. Therefore, the iron piece members 9 and 11 compress a spring (not shown) disposed in the attachment portions 8c and 10c, and a large flange portion which is a part of the spring is not attached to the attachment portions 8c and 10c. is seperated.

  When the release button is pressed at the time of the next shooting, first, each of the electromagnets is energized. As a result, when the iron piece members 9 and 11 are attracted and held by the iron core members 6 and 7, the pressing force applied to the driven portion 12c by the member on the camera body side is released. It rotates counterclockwise by the urging force and returns to the initial position shown in FIG. At this time, the pressing force on the driven portion 8a of the leading blade driving member 8 by the pressing portion 12a of the set member 12 and the roller 10a of the trailing blade driving member 10 by the pressing portion 12b of the setting member 12 Since the pressing force is released, the drive members 8 and 10 are slightly rotated in the clockwise direction by the biasing force of the drive springs (not shown). However, the rotation of the attachment portions 8c and 10c is performed by the iron core member. It is stopped by abutting against the flanges of the iron piece members 9 and 11 adsorbed by the members 6 and 7. FIG. 4 shows the state at that time.

  From this state, when the energization of the two electromagnets is sequentially cut off at time intervals automatically determined by the exposure control circuit, the leading blade driving member 8 and the trailing blade driving member 10 have a strong biasing force. When the object field light is strong by each drive spring (not shown) having a large distance between the leading blade slit forming blade 17 and the trailing blade slit forming blade 22 The imaging surface of the imaging apparatus is exposed by the formed slit. However, in the following description, the case where the leading blade starts the exposure operation and the opening 1a is fully opened and then the trailing blade starts the exposure operation will be described.

  First, when energization to the leading blade electromagnet is interrupted, the holding force of the iron piece member 9 by the iron core member 6 is lost, and the leading blade driving member 8 is caused by the biasing force of the leading blade driving spring (not shown). The arm 13 is rapidly rotated clockwise, and the arm 13 is rotated clockwise by the drive pin 8b. Therefore, the three blades 15 to 17 of the leading blade operate downward as a whole while increasing the overlapping amount of adjacent blades, and open the opening 1 a at the upper edge of the slit forming blade 17. When the opening 1a is fully opened, immediately after that, the driving pin 8b of the leading blade driving member 8 comes into contact with the buffer member 4 attached to the long hole 1b, thereby completing the exposure operation of the leading blade. . FIG. 5 shows the state at that time.

  By the way, as described above, when the driving pin 8b of the leading blade driving member 8 contacts the buffer member 4, the constituent member of the leading blade is greatly deformed by the impact. And if the stress due to the deformation is concentrated at the protruding positions of the protruding portions 15c to 17c of the blades 15 to 17, there is a possibility that they are broken at the protruding position. In the case of the conventional pivot structure, although the protruding heights of the protruding portions 15c to 17c are made higher in the order of the protruding portion 17c, the protruding portion 16c, and the protruding portion 15c, the protruding angles at the protruding positions are as follows. Therefore, the stress concentrated at the protruding positions of the protruding portions 15c to 17c increases in the order of the protruding portion 17c, the protruding portion 16c, and the protruding portion 15c, and the possibility of destruction at the protruding position is the case of the blade 15 Was the biggest. However, in the case of the present embodiment, since the protrusion angle at the protrusion position becomes smaller in the order of the protrusion portion 17c, the protrusion portion 16c, and the protrusion portion 15c, the difference in stress concentrated at the protrusion positions of the protrusion portions 15c to 17c. In particular, the breakage at the protruding position of the blade 15 is suitably suppressed.

  In this way, when the exposure operation for the leading blade is completed, the current supply to the electromagnet for the trailing blade is cut off. As a result, the holding force of the iron piece member 11 by the iron core member 7 is lost, and the rear blade drive member 10 is rapidly rotated clockwise by the biasing force of the rear blade drive spring (not shown). The arm 18 is rotated clockwise by the pin 10b. Therefore, the three blades 20 to 22 of the rear blades operate downward as a whole while reducing the overlapping amount of adjacent blades, and cover the opening 1 a with the lower end edge of the slit forming blade 22. When the opening 1a is completely covered, immediately after that, the drive pin 10b of the rear blade drive member 10 comes into contact with the buffer member 5 attached to the elongated hole 1c, so that the rear blade exposure operation is performed. finish.

  In this way, even when the drive pin 10b of the rear blade drive member 10 contacts the buffer member 5, the component of the rear blade is largely deformed by the impact. However, as described above, the pivotal support structure of the rear blade is the same as the pivotal support structure of the leading blade, so that the difference in stress concentrated on the protruding positions of the protruding portions formed on the blades 20 to 22 is reduced. In particular, the concentration of stress at the protruding position of the blade 20 is alleviated, and breakage is suitably suppressed. When the rear blade exposure operation is completed, the imaging information accumulated in the imaging device by the above-described exposure is transferred to the storage device, and one shooting is completed. FIG. 1 shows the state at that time.

  Example 2 will be described with reference to FIG. In the present embodiment, the configuration of the shutter blade in the first embodiment is further improved. In addition, the shutter blades of this embodiment can be used for a focal plane shutter having one shutter blade or a focal plane shutter having two shutter blades, like the shutter blade of the first embodiment. In the latter case, it is possible to use the leading blade or the trailing blade, but in the first embodiment, the details are shown in FIG. 2 which is a sectional view of the leading blade. Therefore, the shutter blade of the present embodiment shown in FIG. 6 is also referred to as a leading blade, and is shown in a sectional view similar to FIG. The same reference numerals are used. Note that the overall configuration and operation when the shutter blades of the present embodiment are employed in a focal plane shutter having two shutter blades are the same as those of the first embodiment, and thus the description thereof is omitted.

  As can be seen from FIG. 6, in this embodiment, the three pivot structures are different, but the difference is in the shape of the protruding portions 15 c, 16 c, and 17 c. And each protrusion part 15c, 16c, 17c is the shape of the top surface in which the hole which inserts the connection shaft part 15c, 16c, 17c is carrying out the substantially truncated cone shape similarly to the case of Example 1. The protrusion height is approximately the same as the thickness of one blade in the protrusion 16c rather than the protrusion 17c on the most free end side of the arm 13, and the protrusion height is the same. The protruding portion 15c is similarly higher than the protruding portion 16c.

  As in the case of the first embodiment, the pivotal support structure of this embodiment is characterized in that the protrusion angle of each blade 15, 16, 17 is smaller in the protrusion 16c than in the protrusion 17c, and the protrusion 16c. The protruding portion 15c is smaller than the protruding portion 15c, but the circular protruding positions are not angled and are formed so that the vicinity of the protruding position is a curved surface. Therefore, in the case of the present embodiment, even if the blades 15, 16, and 17 are greatly deformed due to an impact such as when the exposure operation is stopped, the concentration of stress applied in the vicinity of the protruding position can be greatly reduced. The blade breakage is further suppressed than in the case of the pivot structure of Example 1.

  Example 3 will be described with reference to FIG. As with the shutter blades of the first and second embodiments, the shutter blade of the present embodiment can be used for a focal plane shutter having one shutter blade or a focal plane shutter having two shutter blades. In the latter case, it is possible to use a leading blade or a trailing blade. Therefore, in the case of the shutter blade of the present embodiment shown in FIG. 7 as well, in the case of the second embodiment, it is referred to as a leading blade, and is shown in a sectional view similar to FIG. 2 and FIG. The same reference numerals as those in FIGS. 2 and 6 are used for the parts. In addition, description is abbreviate | omitted about the whole structure and operation | movement of a focal plane shutter which employ | adopted the shutter blade | wing of a present Example.

  As can be seen from FIG. 7, in this embodiment as well, the three pivot structures are different, but the difference is in the shape of the protruding portions 15c, 16c, and 17c. And each protrusion part 15c, 16c, 17c is a substantially truncated cone shape similarly to the case of said each Example, The top surface which formed the hole which has inserted the connection shaft part 15c, 16c, 17c The protrusion height of the protrusion 16c is higher than the protrusion 17c on the most free end side of the arm 13 by the thickness of approximately one blade. Similarly, the protruding portion 15c is higher than the protruding portion 16c.

  Unlike the case of each of the above-described embodiments, the pivot support structure of this embodiment is similar to that of the shutter blade (hereinafter referred to as the conventional example) shown in FIG. The protruding angles of 15, 16, and 17 are the same. However, the difference from the pivot structure of the conventional example is that, as in the case of the second embodiment, the protruding positions of the protruding portions 15c, 16c, and 17c are not angled, and the vicinity of the protruding position is a curved surface. It is forming. Also in the case of the present embodiment configured as described above, the concentration of stress applied in the vicinity of the protruding position can be greatly relieved when the blades 15, 16, and 17 are deformed. The blade breakage is suppressed.

  Note that each of the shutter blades of each of the above embodiments has three blades, but the present invention also has four or more blades in the shutter blades having two blades. The present invention can also be applied to the shutter blades.

It is the top view of Example 1 which looked at the state immediately after completion | finish of exposure operation from the photographic lens side. 1 is a cross-sectional view showing a main part of Example 1. FIG. FIG. 2 is a plan view of the first embodiment viewed in the same manner as FIG. 1 and shows a set state (photographing standby state). FIG. 2 is a plan view of the first embodiment viewed in the same manner as FIG. 1 and shows a state immediately before the start of an exposure operation after release. FIG. 2 is a plan view of the first embodiment viewed in the same manner as FIG. 1 and shows a fully opened state of an opening for a photographing optical path. FIG. 3 is a sectional view of Example 2 shown in the same manner as FIG. 2. It is sectional drawing of Example 3 shown similarly to FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Shutter base plate 1a, 2a, 3a Opening part 1b, 1c Long hole 1d, 1e, 1f, 1g, 1h, 1i, 1j Axis 2 Auxiliary base plate 3 Intermediate plate 4, 5 Buffer member 6, 7 Iron core member 8 For front blade Drive member 8a, 12c Driven part 8b, 10b Drive pin 8c, 10c Mounting part 9, 11 Iron piece member 10 Rear blade drive member 10a Roller 12 Set member 12a, 12b Push part 13, 14, 18, 19 Arm 15 , 16, 17, 20, 21, 22 Blade 15a, 15b, 16a, 16b, 17a, 17b Connecting shaft 15c, 16c, 17c

Claims (3)

  Two arms each having one end rotatably attached to each shaft provided on the base plate and having the other end as a free end, and both of the two arms in the length direction of the arms in order It is composed of a plurality of blades that are pivotally supported, and each pivotal support portion of the arm and the blade includes a hole provided on a top surface of a protruding portion formed in a substantially truncated cone shape on the blade, and the arm. Overlay the provided holes, insert the tip of the connecting shaft having a head with a large diameter at one end into the hole from the arm side, and fix the tip to the blade in the protruding part By doing so, the blade is configured to be rotatable with respect to the arm, and moreover, the protruding portion is closer to the blade protruding portion pivoted at a position away from the free end. Protruding height from The protruding portion is formed so that the protruding angle becomes smaller as the protruding portion of the blade is pivotally supported at a position away from the free end. A shutter blade for a focal plane shutter.   2. The focal plane shutter shutter blade according to claim 1, wherein the protruding portion is formed in a curved surface in the vicinity of a protruding position from the blade surface.   Two arms each having one end rotatably attached to each shaft provided on the base plate and having the other end as a free end, and both of the two arms in the length direction of the arms in order It is composed of a plurality of blades that are pivotally supported, and each pivotal support portion of the arm and the blade includes a hole provided on a top surface of a protruding portion formed in a substantially truncated cone shape on the blade, and the arm. Overlay the provided holes, insert the tip of the connecting shaft having a head with a large diameter at one end into the hole from the arm side, and fix the tip to the blade in the protruding part By doing so, the blade is configured to be rotatable with respect to the arm, and moreover, the protruding portion is closer to the blade protruding portion pivoted at a position away from the free end. Protruding height from A shutter blade are formed so as to become higher, the protruding portion, the vicinity extended position from the blade surface, a focal plane shutter for shutter blade, characterized in that it is formed into a curved surface.

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