JP3801682B2 - Focal plane shutter - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a focal plane shutter for a camera in which a leading blade group and a trailing blade group are sequentially moved in the same direction during filming, and a film is exposed by a slit formed by them.
[0002]
[Prior art]
In recent focal plane shutters, the leading blade group and the trailing blade group are made to travel at extremely high speeds, so that each blade group bounces at the stage of stopping the traveling, and in the case of the leading blade group, a part of the exposure opening. Is temporarily covered again, and in the case of the rear blade group, exposure unevenness has been generated by temporarily opening a part of the exposure opening again. Therefore, it is necessary to provide braking means for each of the leading blade group and the trailing blade group, and many proposals have been made and implemented so far. And, as for those braking methods, those that apply braking force directly to the blade, those that apply braking force to the connecting shaft between the arm supporting the blade and the blade, those that apply braking force to the arm itself, and actuating the arm A device that applies a braking force to the front drive member and the rear drive member to be driven is known.
[0003]
As described above, various methods are considered as the braking means. However, as the speed and size of the shutter have increased recently, there is a structural problem. If only one of them is used, the desired effect cannot be obtained sufficiently, and in practice, several types of braking means are used in combination according to the constituent parts of the shutter. The present invention relates to a focal plane shutter in which the end face in the exposure traveling direction of the rear blade group is directly brought into contact with a buffer member and can be suitably stopped without bouncing the rear blade group. Is.
[0004]
Conventionally, in the case of the leading blade group, it is well known and practiced that the end surface of the blade group in the exposure running direction is brought into direct contact with the buffer member. That is, an elastic material such as butyl rubber is used as the buffer member, and this buffer member is disposed in the vicinity of the arm attached so as to be in contact with the arm, and below the exposure opening. In this case, the front blade is elongated in parallel with the lower end edge of the exposure opening so that it can come into contact when the opening of the exposure opening is completed. However, few examples of suitably arranging the buffer member having such a role with respect to the rear blade group are known and not implemented.
[0005]
[Problems to be solved by the invention]
Conventionally, there is a reason why the buffer member is not provided for the rear blade group as described above. That is, when this type of focal plane shutter is viewed from the photographic lens side, the arm of the leading blade group and the arm of the trailing blade group share a working area between the arms. Therefore, the arm of the rear blade group moves to the area where the arm of the front blade group existed before the exposure travel during the exposure travel. Therefore, it is not easy to provide a buffer member in such a common area so as to surely contact only the end face of the arm of the rear blade group.
[0006]
The present invention has been made in order to solve such problems, and an object of the present invention is to provide a buffer member that is in direct contact with the end face of the rear blade group in the exposure traveling direction, and expose the rear blade group. It is an object of the present invention to provide a focal plane shutter that is suitably provided at a stop position after traveling so as to suppress the bounce of the rear blade group and absorb the impact force.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, a focal plane shutter according to the present invention includes two substrates each having an opening for forming an exposure opening and attached to each other at a predetermined interval, and the opening of the opening. A front blade group formed by supporting a plurality of front blades on a plurality of arms rotatably attached to one of the substrates at a side position, and one of the substrates at a side position of the opening. A rear blade group in which a plurality of rear blades are supported by a plurality of rotatably mounted arms, and a traveling area of the leading blade group and the traveling of the rear blade group disposed between the two substrates. And at least one of the substrate and the intermediate plate forming the running area of the rear blade group at a lateral position of the opening to which the arm of the rear blade group is attached. On the other hand, the end face is the leading blade An attachment member that faces the traveling area of the front blade and is attached so as to be always in contact with one of the leading blades that is closest to the intermediate plate, and exposure of the rear blade group that is attached to the attachment member And a cushioning member with which an end face of one arm of the rear blade group abuts at a travel end position .
In that case, preferably, the mounting member is a shaft member.
[0008]
In order to achieve the above object, a focal plane shutter according to the present invention includes two substrates each having an opening for forming an exposure opening and attached to each other at a predetermined interval, and the opening. A plurality of leading blades are supported on a plurality of arms rotatably attached to any of the substrates at a side position of the portion, and are supported on the most distal end side of the arms among the plurality of blades. A plurality of front blades supporting a plurality of rear blades on a group of leading blades whose blades are slit-forming blades and a plurality of arms rotatably attached to any of the substrates at a side position of the opening. Of these blades, the blade supported on the most distal end side of the arm is used as a slit forming blade, and at the end of the exposure operation, the end surface of the tip portion of one of the arms protrudes toward the exposure travel side from the slit forming blade. A rear blade group configured as described above, an intermediate plate that is disposed between the two substrates and separates the traveling region of the leading blade group and the traveling region of the rear blade group, and the traveling of the rear blade group A buffer member attached to at least one of the substrate and the intermediate plate forming a region and contacting the protruding end surface of the arm of the rear blade group at the exposure travel end position of the rear blade group. Yes.
In this case, preferably, the buffer member is attached to an attachment member attached to at least one of the substrate and the intermediate plate forming the traveling area of the rear blade group.
Preferably, the attachment member is a shaft member, and one end face thereof faces the traveling area of the leading blade group, and the end face is attached at a position where it can always contact one of the leading blades. To be.
Further, in the focal plane shutter according to the present invention, preferably, at least one of the substrate and the intermediate plate forming the traveling area of the rear blade group is made of synthetic resin, and the mounting member is integrally formed therewith. To be formed by .
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Two embodiments of the present invention will be described. The first embodiment is shown in FIGS. 1 and 2, and the second embodiment is shown in FIGS. 3 and 4. Of the parts and parts shown in the drawings, the first embodiment is substantially the same between the embodiments. The same reference numerals are used for what is considered to be the same, and a specific description thereof will be given in principle in the description of the first embodiment, and the description of the other embodiment will be omitted to avoid duplication. I will decide.
[0010]
First, a first embodiment will be described with reference to FIGS. FIG. 1 is a plan view of the present embodiment, and FIG. 2 is a cross-sectional view of the main part of FIG. The shutter substrate 1 is provided with an opening 1a for forming an exposure opening and two arc-shaped holes 1b and 1c. Shafts 1d and 1e are erected on the surface side of the shutter substrate 1, and a leading blade driving member is attached to the shaft 1d and a trailing blade driving member is rotatably attached to the shaft 1e. Since the structure of these drive members is well known, illustration is abbreviate | omitted. And the drive pin provided in each drive member penetrates said hole 1b, 1c, and it fits into the long hole formed in the arm of each blade group mentioned later in the back surface of the shutter board | substrate 1. FIG.
[0011]
On the rear side of the shutter substrate 1, an intermediate plate 2 and an auxiliary substrate 3 are attached in order at a predetermined interval to form two blade chambers. Among these, the blade chamber formed between the shutter substrate 1 and the intermediate plate 2 is a traveling region of the leading blade group, and the blade chamber formed between the intermediate plate 2 and the auxiliary substrate 3 is traveling of the trailing blade group. It is an area. Further, the intermediate plate 2 and the auxiliary substrate 3 are formed with openings having substantially the same shape as the openings 1a formed in the shutter substrate 1, and the left end shape of the intermediate plate 2 in FIG. It is shown.
[0012]
Shafts 1f, 1g, 1h, and 1i are erected on the back side of the shutter substrate 1. The front blade group arms 4 and 5 are disposed on the shafts 1f and 1g, and the rear blade group is disposed on the shafts 1h and 1i. Arms 6 and 7 are rotatably attached. Four leading blades 8 are attached to the arms 4 and 5, and these arms 4 and 5 and the leading blade 8 constitute a leading blade group. Further, the driving pin of the above-described leading blade driving member (not shown) is fitted into the long hole 4 a formed in the arm 4. In this leading blade group, as is well known, the arms 4 and 5 are arranged on the shutter substrate 1 side, and four blades 8 are arranged on the intermediate plate 2 side. From the tip toward the shafts 1f and 1g, the slit forming blades are attached in order. FIG. 1 shows a state where the four leading blades 8 are overlapped and stored below the opening 1a.
[0013]
Further, four rear blades 9 are attached to the arms 6, 7, and these arms 6, 7 and the rear blade 9 constitute a rear blade group. A long hole 6a is formed in the arm 6 so that a driving pin of a driving member for a trailing blade (not shown) is fitted. In such a rear blade group, opposite to the front blade group, the arms 6 and 7 are disposed on the auxiliary substrate 3 side, and the rear blade 9 is disposed on the intermediate plate 2 side. The four blades 9 are attached to the arms 6 and 7 in the same manner as in the case of the leading blade group, and are attached in order from the slit forming blades toward the shafts 1h and 1i from the tip. In FIG. 1, these four rear blades 9 are in a developed state and cover the opening 1a.
[0014]
As shown in FIG. 2, a shaft member 10 is caulked on the auxiliary substrate 3. A buffer member 11 made of an elastic material such as a ring-shaped butyl rubber is attached to the shaft member 10. Further, the front end surface of the shaft member 10 is configured to face a blade chamber of a leading blade group from a circular hole 2 a formed in the intermediate plate 2. The reason for this configuration is due to manufacturing reasons. If there is no particular problem, the end surface of the shaft member 10 may be brought into contact with the intermediate plate 2 without forming the hole 2a. As can be seen from FIG. 1, such a buffer member 11 is disposed at a lateral position on the left side of the opening 1 to which the arms 4, 5, 6, and 7 are attached.
[0015]
By the way, in FIG. 1, the leading blade 8 is in a superimposed state and is stored below the opening 1a, and the trailing blade 9 is in a deployed state and closes the opening 1a. Indicates the completed state. From this state, the shutter is set in conjunction with the winding of the film. In the setting operation, the presence of the shaft member 10 and the buffer member 11 does not cause any trouble. That is, of the four leading blades 8, the blade 8a attached to the arms 4 and 5 at the position closest to the shafts 1h and 1i, in other words, the blade 8a closest to the intermediate plate 2 is shown in FIG. A part is in the position which overlaps with the tip end face of shaft member 10. The blade 8a always overlaps the front end surface of the shaft member 10 even during the setting of the shutter and in the set completion state. Therefore, the end surface of the blade 8a in the traveling direction does not interfere with the shaft member 10 and the buffer member 11 at all. In this way, the shutter is set without hindrance, and the four leading blades 8 are in a set state covering the opening 1a.
[0016]
Thereafter, when the shutter is released, the leading blade group and the trailing blade group sequentially perform exposure running as is well known, and at this time, the leading blade group can operate without any trouble for the reason described above. Each blade group is in the state shown in FIG. 1 after the end of exposure travel. At the final stage, the rear blade group abuts the end surface of the arm 7 in the exposure travel direction against the buffer member 11 to suppress bounce. And the shock is absorbed to stop. Therefore, a part of the opening 1a is not instantaneously opened again.
[0017]
As can be understood from the above description, the hole 2a of the intermediate plate 2 may have any shape as long as the blade 8a always overlaps the tip surface of the shaft member 10, and depending on the case, the shaft member The intermediate plate 2 does not have to protrude at a position near 10. When the auxiliary substrate 3 is made of a synthetic resin, the shaft member 10 may be formed by integral molding, and the shaft member 10 only needs to function as a mounting member for the buffer member 11 and is limited to a shaft shape. Is not to be done. Further, the shape of the buffer member 11 is not limited, and may be adhered to an attachment member such as the shaft member 10 or may be directly attached to the auxiliary substrate 3 in some cases.
[0018]
Next, a second embodiment of the present invention will be described with reference to FIGS. FIG. 3 is a plan view of the present embodiment, and FIG. 4 is a cross-sectional view of the main part of FIG. The configuration of the present embodiment is different from the first embodiment in that the mounting configuration of the buffer member 11 and the shape of the arm 6 are different. As shown in FIG. 4, the shaft member 12 of this embodiment has one end caulked to the intermediate member 2, the other end fitted into the hole of the auxiliary board 3, and attached with a screw 13 from the opposite side. Yes. And the attachment position of this buffer member 11 is a downward position of the opening part 1a, as shown in FIG. In FIG. 3, the leading blade group is not shown, but the exposure running completion state is shown as in FIG. As can be seen from this figure, the arm 6 of this embodiment has a tip extending from the connecting portion of the slit forming blade, and its end surface comes into contact with the buffer member 11 at the end of the exposure running. .
[0019]
According to the present embodiment, the end surface of the shaft member 12 that is crimped to the intermediate plate 2 faces the blade chamber of the leading blade group, but does not protrude, but even if it protrudes, this position Then, since it can always be brought into contact with the leading blade 8a arranged closest to the intermediate plate 2 shown in FIG. 1, no trouble occurs as described above. Further, according to the present embodiment, the arm 6 that is directly actuated by the drive pin of the rear blade drive member is brought into contact with the buffer member 11, so that the bounce is suppressed as compared with the first embodiment. It is easy to reduce the possibility of breaking the blade group. In addition, the description of the various modifications described in the first embodiment can be applied to the present embodiment as far as possible.
[0020]
In each of the above embodiments, the shutter substrate 1 and the intermediate plate 2 form the blade chamber of the leading blade group, and the intermediate plate 2 and the auxiliary substrate 3 form the blade chamber of the rear blade group. There is also known a shutter in which a blade chamber configuration is reversed and a blade chamber of a rear blade group is formed by a shutter substrate 1 and an intermediate plate 2. Therefore, in this case, if the auxiliary substrate 3 is the shutter substrate 1, the object of the present invention can be achieved. In addition, there is a shutter that causes each blade group to travel upward from the lower side of the drawing during exposure travel, but the present invention is equally applicable to such a type.
[0021]
【The invention's effect】
As described above, according to the present invention, the buffer member that directly contacts the end face of the rear blade group in the exposure traveling direction is provided at the stop position after the exposure traveling of the rear blade group. It is suitable for suppressing the impact and reducing the impact.
[Brief description of the drawings]
FIG. 1 is a plan view showing a first embodiment of the present invention.
FIG. 2 is a cross-sectional view of the main part of FIG.
FIG. 3 is a plan view showing a second embodiment of the present invention.
4 is a cross-sectional view of the main part of FIG. 3;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Shutter board | substrate 1a Opening part 1b, 1c, 2a Hole 1d, 1e, 1f, 1g, 1h, 1i Axis 2 Intermediate | middle board 3 Auxiliary board | substrate 4, 5, 6, 7 Arm 4a, 6a Long hole 8 Leading blade 9 Rear blade 10 , 12 Shaft member 11 Buffer member 13 Screw

Claims (6)

Two substrates each having an opening for forming an exposure opening and attached to each other at a predetermined interval, and rotatably attached to one of the substrates at a side position of the opening. A group of leading blades formed by supporting a plurality of leading blades on a plurality of arms, and a plurality of trailing blades on a plurality of arms rotatably attached to any of the substrates at a side position of the opening. A rear blade group that is supported, an intermediate plate that is disposed between the two substrates and that separates a traveling region of the leading blade group and a traveling region of the rear blade group, and an arm of the rear blade group. At least one of the base plate and the intermediate plate that form the traveling area of the rear blade group at a side position of the attached opening, one end surface faces the traveling area of the leading blade group. Always contact one of the leading blades closest to the intermediate plate. And is mounted attachment member so as to obtain, the end surface of one arm of the rear blade group at the exposure end of travel position of the rear blade group is attached to the mounting member and a cushioning member abutting Focal plane shutter characterized by. The focal plane shutter according to claim 1, wherein the mounting member is a shaft member. Two substrates each having an opening for forming an exposure opening and attached to each other at a predetermined interval, and rotatably attached to one of the substrates at a side position of the opening. A front blade group in which a plurality of front blades are supported by a plurality of arms and the blade supported on the most distal end side of the plurality of blades is a slit forming blade, and a lateral position of the opening A plurality of blades that are rotatably attached to any one of the substrates, and a blade that is supported on the tip end side of the arm among the plurality of blades is a slit forming blade. At the end of the exposure operation, the end face of the tip of one of the arms is arranged between the two blades and the rear blade group formed so that the end face of the arm protrudes more toward the exposure travel side than the slit forming blade. The leading blade group travels And an intermediate plate that separates the travel region of the rear blade group, and an exposure travel of the rear blade group that is attached to at least one of the substrate and the intermediate plate that form the travel region of the rear blade group A focal plane shutter, comprising: a buffer member with which the protruding end face of the arm of the rear blade group abuts at an end position. 4. The focal plane shutter according to claim 3, wherein the buffer member is attached to an attachment member attached to at least one of the substrate and the intermediate plate forming a traveling area of the rear blade group. 5. . The attachment member is a shaft member, and one end surface thereof faces the traveling region of the leading blade group, and the end surface is attached at a position where the end surface can always contact one of the leading blades. The focal plane shutter according to claim 4. The at least one of the board and the intermediate plate forming the traveling area of the rear blade group is made of synthetic resin, and the mounting member is formed by integral molding therewith. , 2, 4 or 5.

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