JPH0594833U - Blade support device for focal plane shutter for camera - Google Patents

Abstract

(57) [Summary] [Object] To provide a blade support device suitable for higher speed in a compact focal plane shutter having a structure in which a load is not concentrated on an arm. [Structure] Of two arms that axially support a slit forming blade, one main arm is coupled and supported by one main arm, and the other axial support portion is coupled and supported by the other main arm and auxiliary arm. A focal plane shutter having a plurality of divided blades. [Effect] The blades can be easily caulked, and the weight of the blades divided into the arms is not concentrated.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a blade supporting device for a focal plane shutter for a camera, which is composed of a plurality of blade groups.

[0002]

[Prior Art]

 Conventionally, the configuration of a blade support device for a focal plane shutter for a camera is such that a plurality of divided blade groups are sequentially pivotally supported from the respective tips of two arms pivotally supported on one side of the machine frame to the middle. (Japanese Patent Publication No. 54-191753). In this type of shutter, all the blades are directly or indirectly rotatably supported by the respective arms, so that the operating efficiency is good and the shutter is suitable for high speed operation.

On the other hand, in order to improve the above-mentioned shutter in response to the demand for the compactness of today's cameras, as disclosed in Japanese Utility Model Publication No. 57-57367, a part of two arms is provided via an auxiliary arm. It is known that the blades are pivotally supported.

Further, for downsizing, a shutter in which each blade group is further subdivided and which is pivotally supported by two arms is also realized.

[0005]

[Problems to be solved by the device]

 However, such an improved shutter for a compact size has poor durability and is easily damaged because the weight of each of the auxiliary arm or the subdivided blade is added to the two arms. ..

Therefore, an object of the present invention is that the load is not concentrated on each arm even when it is made compact, and that each blade is easily caulked to the arm, which is suitable for higher speed. It is to provide a new blade support device.

[0007]

[Means for Solving the Problems]

 In order to achieve such an object, it is composed of a blade group, first and second main arms, and an auxiliary arm, and the blade group is composed of a slit forming blade and a subsequent cover blade, and It is divided into a plurality of parts that cover the passage window, and the base end portions of the first and second main arms are rotatably supported by one side of the light passage window to form a parallel link mechanism. The base end of the auxiliary arm constitutes a parallel link mechanism with both main arms and is rotatably supported at a position different from that of each base end. The forming blades are rotatably supported at the tips of the first and second main arms, and one of the axes of all the blades of the main arm is the second main arm. Is rotatably supported, and the first main arm and the auxiliary arm of the main arm rotate the other shaft of each blade. The distance between the shaft support of the base end of the auxiliary arm and the shaft support of the cover blade in the auxiliary arm is in the first and second main arms. The distance is shorter than the distance between the shaft support of the base end and the shaft support of the slit forming blade.

[0008]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings. 1 (a) to 1 (f) each show the principle of a blade support mechanism according to the present invention, the most basic structure of which is shown in FIG. 1 (a). ..

In FIG. 1A, on the left edge of the substrate H, first and second main arms A and B and an auxiliary arm C are rotatably rotatably supported with their base ends in a vertical line. I am doing it. Further, the shaft supporting portion at the base end portion of the auxiliary arm C is on the downward extension of the line connecting the shaft supporting portions at the base end portions of the first and second main arms A and B. Further, the respective tips of the first and second main arms are rotatably connected to the left end of a slit forming blade (hereinafter simply referred to as "slit blade") E. A trailing cover blade (hereinafter simply referred to as “cover blade”) F has its left upper end portion rotatably connected at the center of the first main arm A, and further has its left lower end portion at the lowest position. It is rotatably and rotatably connected to the tip of the auxiliary arm C.

As described above, one of the blades E and F is pivotally supported by the first main arm A on one pivotal support portion. The first and second main arms A and B form a parallel link, and the auxiliary arm C forms a parallel link with the first main arm A.

The distance between the pivotal support portion of the base end portion of the auxiliary arm C and the pivotal support portion of the cover blade F depends on the distance between the base end portions of the first and second main arms A and B. It is shorter than the distance between the shaft support and the shaft support of the slit forming blade E.

As a result, one of the slit blade E and the cover blade F is pivotally supported by the uppermost first main arm A, and the other is pivotally supported by the second main arm B and the auxiliary arm C. At the time of connection, it is possible to stably support the base end of each arm as a guide, so that the caulking connection of each blade can be ensured. Moreover, since the weight of each blade is axially supported by the three arms in a shared manner, it is not concentrated. In FIG. 1B, the auxiliary arm C is placed above the first and second main arms B and A, and the slit blade E is supported by the first and second main arms B and A, while the slit Device for supporting one side of the covering blade F extending laterally from the blade E by the auxiliary arm C and the second lowest main arm A located farthest from the auxiliary arm C Indicates. The other structure is substantially the same as that of FIG.

Further, the drawings from FIG. 1 (c) onward show the use of two cover blades. In FIG. 1 (c), the slit blade E is shown as the first and second main arms A and B. One of the cover blades F and G is supported by the uppermost main arm A, and the other side is supported by the lowermost auxiliary arm C. That is, one of the blades of all the blades is connected to the first main arm A. The first and second main arms A and B form a parallel link, and the first main arm A and the auxiliary arm C also form a parallel link. Further, FIG. 1 (d) shows the auxiliary arm C of FIG. 1 (c) in the uppermost position, and the other structure is substantially the same as that of FIG. 1 (c). The one shown in FIG. 1 (e) is characterized by using four arms A, B, C and D. The first main arm A and the second main arm B are used. Each of the tips is rotatably connected to the slit blade F. The middle of the first main arm A and the tip of the first auxiliary arm C are rotatably connected to the first cover blade F. Further, the second cover blade G is rotatably connected to the intermediate portion of the first main arm A and the respective tips of the second auxiliary arm D farthest from the main arm A. is there. One of the blades of each blade is connected to the first main arm A.

The one shown in FIG. 1 (f) has been further improved in order to conform to the substance, and the slit blade E and the cover immediately below the slit blade E are provided by the first and second main arms A and B. The blade supports two blades of the blade F, and further supports the last succeeding cover blade G by the middle of the first main arm A and the tip of the auxiliary arm C. Other configurations are substantially the same as those described above.

In such a device of FIG. 1, when each blade is subdivided in order to make the shutter compact, an arm is added to increase the weight which is inevitably increased as the number of blades increases. To share the weight to avoid concentration, and to facilitate crimping of the arm and each blade at that time.

In any of the devices (a) to (f) described above, since one shaft support of all the blades is connected to one main arm, each blade connected by a parallel link is used. And each arm can be sequentially coupled in a relatively cohesive fashion without the need to handle them individually. That is, since the other arm always forms a parallel link with respect to one main arm, if one main arm is handled as a center, the other links are less likely to be mixed.

Therefore, in the caulking connection for connecting each blade and each arm, it becomes easy to fit the base end portion, which is the center of rotation of each arm, into the processing jig as a guide and sequentially perform the processing.

FIG. 2 shows an embodiment of the present invention which embodies the above-mentioned principle.

A light passage window 2 is formed on the substrate 1, and the left side of the light passage window 2 is vertically spaced from each other and is used for axial support of the second main arm 3 and the first main arm 4. 2 shafts 3a and 4a are provided, and the second main arm 3 and the base end portions of the first main arm 4 are rotatably supported on the respective shafts. .. These first and second main arms 4 and 3 hold the slit blade 6 so as to move vertically along the light beam passage window 2. The distance between the two shafts 6a and 6b on the slit blade 6 is the same as that of the shafts 3a and 4a, and the tips of the main arms 3 and 4 are rotatably connected to the shafts. Therefore, the substrate 1, the main arms 3 and 4, and the slit blade 6 constitute a parallel link mechanism.

Further, the base arms of the first cover blades 7 following the slit blades 6 are planted therein and rotatably supported by shafts 7a and 7b by the main arms 3 and 4.

On the other hand, the base end portion of the auxiliary arm 5 is rotatably supported by the shaft 5a, and the position of this shaft is above the second main arm 3, In addition, it is provided on an extension of a line connecting the shafts 3a, 4a of both main arms 3, 4. The auxiliary arm 5 forms a parallel link with one of the main arms 4 and swings in conjunction with the main arm 4.

By the way, the auxiliary arm 5 and the lowermost first main arm 4 are connected to the base ends of the second and third cover blades 8 and 9 via shafts 8a, 8b, 9a and 9b. It is connected to rotate freely. The distance between the shafts 8a-8b and 9a-9b coincides with the distance between the shaft 5a of the auxiliary arm 5 and the shaft 4a of the first main arm 4.

In this way, the second and third cover blades 8 and 9 are configured to move stably. Further, all the blades 6, 7, 8 and 9 are connected to the first main arm 4 by one of the shaft supporting portions 6b, 7b, 8b and 9b.

The distance between the shaft supporting portion 5a of the base end portion of the auxiliary arm 5 and the shaft supporting portion 9a of the cover blade 9 is determined by the base end portions of the first and second main arms 4 and 3. It is shorter than the distance between the shaft supporting parts 4a, 3a of the above and the shaft supporting parts 6a, 6b of the slit forming blade 6. The first main arm 4 is provided with an operation hole 4c which can be engaged with a drive pin (not shown). Furthermore, the weight of all the blades 6, 7, 8 and 9 is shared by the three shafts 3a, 4a and 5a.

Next, the operation of the embodiment will be described. When the first main arm 4 driven by the drive pin through the operation hole 4c rotates about the shaft 4a as a fulcrum, the second main arm 3 constituting the parallel link mechanism and the auxiliary arm 5 located above the second main arm 3 are formed. Also, the slit blade 6 and the covering blades 7, 8 and 9 following the slit blade 6 are horizontally swung together with the slit blade 6 and are moved along the light beam passage window 2 while being held horizontally.

By the way, when the main arm 4 shown in FIG. 2 is driven, distortion occurs in the direction orthogonal to the movement direction of the arm at the initial stage of the movement to cause friction between the blades. By providing the element, the energy is instantaneously absorbed, the starting property is improved, and it is extremely effective for a shutter that performs high speed control such as 1/4000 or 1/8000 seconds.

Note that the main arms A and B and the auxiliary arm C are not limited to axially supporting the base ends of the main arms A and B in a vertical line, and each pair of arms forms a parallel link. It is enough to configure.

[0028]

[Effect of the device]

 According to the present invention, the blade divided into a plurality of parallel links is rotatably pivotally supported, and the base end of each arm of each parallel link is pivotally supported on the substrate of a camera focal plane shutter. In the blade support device, one main arm of the two main arms that axially supports the slit-forming blades is coupled to and supports one axial support portion of the other blade, and the other axial support portion of the other main arm and Since it is connected to and supported by the auxiliary arm, the weight of the divided blades is shared by the base end of each arm and is not concentrated at the base end of the main arm. Moreover, the caulking connection between the arms and the blades can be processed relatively easily, so that the connecting portion can be made surely strong.

Further, as compared with the conventional one in which all the blades are pivotally supported by one set of arms, even when a part having a slight bend is used in one of the arms or the blades, it is caused by friction between them. The decrease in exercise performance is reduced. Further, when the main arm is driven, in the initial stage of the movement, distortion is caused in the direction orthogonal to the movement direction of the arm and friction is generated between the blades, but the provision of the auxiliary arm prevents instantaneous energy absorption. Therefore, the startability is improved, and it is extremely effective for a shutter that performs high speed control.

[Brief description of drawings]

1A to 1F are explanatory views showing the principle of the present invention.

FIG. 2 is a front view of an apparatus showing an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Substrate, 2 Ray passage window 3,4 Main arm 3a-9a axis 6b-9b axis 5 Auxiliary arm 6 Slit forming blade 7,8,9 Subsequent cover blade

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshiaki Hirai 934-13 Shikato, Yotsukaido-shi, Chiba Seiko Optical Co., Ltd. Within the corporation

Claims (1)

[Scope of utility model registration request] 1. A blade group, first and second main arms, and an auxiliary arm, wherein the blade group includes a slit forming blade and a succeeding cover blade, and a plurality of cover blades cover the light passage window. The base ends of the first and second main arms are rotatably supported on one side of the light passage window to form a parallel link mechanism. A base end portion of the arm constitutes a parallel link mechanism with the both main arms and is rotatably supported at a position different from each base end portion. , 2 is rotatably supported at the tip of the main arm, and one shaft of all blades is rotatably supported on the second main arm of the main arms. Of the main arms, the first main arm and the auxiliary arm have the other shafts of the blades rotatably supporting the blades. In addition, the distance between the pivotal support portion of the base end portion of the auxiliary arm and the pivotal support portion of the cover blade is such that the slits and the pivotal support portion of the base end portion of the first and second main arms are formed. A blade support device for a focal plane shutter for a camera, which is shorter than a distance between the blade and a shaft support.