JP2503375B2 - Shade feather for camera - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shading blade for a camera, and more specifically, to a shading blade for a camera such as a focal plane shutter of a camera or a shutter blade of a lens shutter or a diaphragm blade which is required to move at high speed. Regarding

[0002]

2. Description of the Related Art For example, the shutter speed has been increased in order to increase the photographing area of a focal plane shutter. However, the structure of the light-shielding blade using the duralumin plate has a limit in reducing the thickness because the rigidity is maintained. Yes, the shutter speed is limited to about 1/4000 seconds. Therefore, in order to achieve higher speed, a blade using a carbon fiber reinforced thermosetting resin sheet that is lightweight and has high specific rigidity has been developed.

Conventionally, the structure of a blade using this carbon fiber reinforced thermosetting resin sheet is such that a unidirectional reinforced prepreg in which carbon fibers are arranged in one direction is made to have the directions of the carbon fibers orthogonal or parallel. As described above, it has a structure in which a plurality of layers are laminated and solidified by hot pressing (Actually developed 60-63).
825, and Japanese Utility Model Laid-Open No. 60-65726).

The carbon fiber of the surface layer is oriented in the longitudinal direction of the blade so that the carbon fiber of the cut end surface does not damage other blades when the blade slides. Are oriented in the width direction of the blade, that is, in the sliding direction.

[0005]

However, the carbon fiber of the intermediate layer is pulled out in the vicinity of the end when the blade shape is punched out by cutting or cutting, and the carbon which is pulled out and protrudes from the end. There is a problem that the fibers damage other blades when the light-shielding blade is used.

Further, there is a problem that peeling occurs from the laminated boundary surface when the shape of the blade is removed.

Therefore, an object of the present invention is to prevent the carbon fibers from being pulled out from the end face of the cut, to prevent the other blades from being damaged during use, to further secure the necessary rigidity, and to laminate when removing the shape. It is to provide a light-shielding blade for a camera that does not peel off from the boundary surface.

[0008]

In order to achieve the above-mentioned object, the light-shielding blade for a camera of the present invention is arranged substantially in the longitudinal direction.
A prepreg sheet that slides in a direction orthogonal to each other, in which carbon fibers are oriented in one direction and is impregnated with a matrix resin is laminated, and the prepreg sheet of the surface layer among the laminated prepreg sheets is carbon. The orientation direction of the fibers is the longitudinal direction of the blade, and the prepreg sheet of the intermediate layer sandwiched between the surface layers has the orientation direction of the carbon fibers in the width direction of the blade, and the intermediate layer has a higher degree of oxidation of the carbon fibers than the surface layer. It's big.

[0009]

[Function] Since the carbon fiber of the intermediate layer is highly oxidized,
Bonding force between the matrix resin is increased, thus when the shape punching, the ends of the carbon fibers of the intermediate layer is drawn out decreases and protrude from the end <br/> face, damage to other blades therefor
Can be suppressed.

Further, since the carbon fiber of the intermediate layer has a large bonding force with the matrix resin, the carbon fiber of the intermediate layer can be prevented from peeling from the laminated boundary surface when the shape is removed.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings. FIG. 2 is a plan view of one light-blocking blade 1, and FIG. 1 is an enlarged end view of the portion A in FIG. Figure 1,
As shown in FIG. 2 , the light-shielding blade 1 is composed of three layers, and both surface layers 2 and 2 have carbon with a diameter of 7 to 10 μm, for example.
The fibers 3 are oriented in the longitudinal direction of the blade, and this carbon fiber
Matrix resin 4 are impregnated with. In addition, the intermediate layer 5
Have carbon fibers 6 of the same diameter oriented in the width direction of the blade and impregnated with a matrix resin 7.

The carbon fiber 6 of the intermediate layer 5 has a large degree of oxidation and has a large bonding force with the matrix resin 7. Since the intermediate layer 5 has a large degree of oxidation of the carbon fibers 6, the carbon fibers are prevented from being pulled out, and
Therefore, damage to other blades can be suppressed, but on the other hand,
The rigidity that is lower.

On the other hand, the surface layer 2 has high rigidity but carbon fiber
Longitudinal end faces (faces located at both ends in the longitudinal direction, that is, length
It is easy to pull it out from the surface orthogonal to the hand direction). But charcoal
Since the fibers are arranged along the longitudinal direction,
Surface (surface located at both ends in the width direction, that is, parallel to the longitudinal direction
Surface). The light shielding blade of the present invention is in the longitudinal direction.
Since it slides in the direction orthogonal to, the end face parallel to the longitudinal direction
The carbon fibers project from the upper end surface and the lower end surface in FIG.
It is easy to damage when overlapping with other blades, but in the longitudinal direction
Projecting from orthogonal planes (right end face and left end face in FIG. 2)
However, it does not hurt other feathers very much. Obey
By increasing the degree of oxidation of the intermediate layer 5
It can prevent root damage.

Further , the blade 1 is bent and deformed in the width direction.
Since it is difficult to do so, its rigidity can be made smaller in the longitudinal direction as compared with the rigidity in the longitudinal direction in which the blades easily bend .
It has high rigidity, and the rigidity decreases slightly in the width direction.
However, the rigidity required for the blades is secured as a whole.

Next, a method for manufacturing this camera light-shielding blade will be described. The prepreg sheets for both surface layers 2 and 2 are formed in the same manner as the conventional one. That is, the carbon fiber 3 is 400 ° C. in the atmosphere.
At a temperature of several tens of hours for oxidation to form pores on the surface, the carbon fibers 3 are aligned in one direction and arranged, and a thermosetting resin such as epoxy or unsaturated polyester is placed on the carbon fibers 3. The prepreg sheet in the B stage state is formed by impregnating the matrix resin 4 of

On the other hand, the carbon fiber 6 used for the prepreg sheet of the intermediate layer 5 is heated in the atmosphere at a temperature of 400 ° C. longer than the heating time of the carbon fiber 3 of the surface layer. When the heating time becomes long, excessive oxidation occurs, CO ₂ is generated, the surface of the carbon fiber is roughened, and many fine irregularities are generated to increase the surface area. Therefore, on the surface of the carbon fiber 6, ketone, rawton,
More oxygen functional groups such as hydroxyl groups and carboxyl groups attach. Although the strength and rigidity of the fiber decrease as the degree of oxidation increases, the maximum heating time is determined within the limit that the rigidity required in the width direction of the blade 1 (see FIG. 2) is secured. . The carbon fibers 6 are aligned in one direction and arranged in the same manner as in the prior art, and the same matrix resin 7 as described above is arranged thereon.
To form a prepreg sheet in the B stage state.

Next, the prepreg sheet used for both surface layers 2 and the prepreg sheet used for the intermediate layer 5 are laminated so that the orientation directions of the fibers thereof are at right angles to each other and cured by hot pressing. Then, the matrix resins 4 and 7 are hardened and the carbon fibers 3 and 6 are fixed in the matrix resins 4 and 7, respectively, to form one fiber reinforced plastic (FRP) sheet. Since the carbon fiber 6 of the intermediate layer has an excessive degree of oxidation, in particular, since more oxygen functional groups are generated, chemical bonds such as hydrogen bond and ester bond with the matrix resin 7 are strongly generated, It is very firmly fixed in the matrix resin 7.

[0018] Then, as in the direction of the carbon fibers 3 of the surface layers 2 and 2 is the longitudinal direction of the blade 1 and the alignment direction of the carbon fiber 6 of the intermediate layer is positioned such that the width direction of the blade 1 Then, the shape of the blade 1 is removed. At this time, since the carbon fiber 6 of the intermediate layer is firmly bonded to the matrix resin 7, peeling at the boundary surface between the intermediate layer 5 and both surface layers 2 1 and 2 is extremely reduced during shape removal. .

Further, since the carbon fibers 6 of the intermediate layer 5 are firmly fixed to the matrix resin 7, the longitudinal direction of the blade 1
At the end face parallel to the direction (end surfaces of the upper and lower in FIG. 2), the cut end surface hardly drawn from the end <br/> face, carbon fibers 6
The amount of protrusion is small.

Since the carbon fibers 3 of the surface layers 2 and 2 are cut in the direction parallel to the fiber direction on the end face parallel to the longitudinal direction of the blade 1, the cut of the fiber is hardly formed,
The end face is smooth.

The blade 1 thus formed is shown in FIG.
As shown in the figure, the holes 1a are attached to the connecting shafts 12 and 13 so as to be attached to the arms 10 and 11, and the other three blades 15, 16 and 17 are similarly attached to the arms 9, 10, and
It is attached to 11. These arms 9, 10, 11
Is fixed to the blade receiving plate 19, and the window hole portion 19a has blades 1 and 1
The shutter is configured by being blocked by 5, 16, and 17. When the rotating part 18 is rotated by a predetermined means (not shown), the blades 1, 15, 1 are moved by the parallel link mechanism.
6, 17 are substantially parallel to each other and substantially in the longitudinal direction of the blade
The shutter is opened and closed by sliding in a direction orthogonal to (the vertical direction in FIG. 3) .

[0022] Here the wing 1,15,16,17 is lightweight, also is enhanced longitudinal rigidity carbon fibers 3, further width direction of the rigidity required minimum vanes are secured, It is possible to open and close at high speed without any problems.

The carbon fiber 6 of the intermediate layer 5 of the blade 1 is
Although oriented in the sliding direction of the blades, the carbon fiber 6 is long
Since it does not project from the end face parallel to the direction , other blades and the like are not damaged, and the durability of the shutter and the like can be improved.

The carbon fibers 3 of the surface layers 2 and 2 of the blade 1
Even if it is pulled out from the left and right ends of Fig. 2,
Slides in a direction substantially perpendicular to its longitudinal direction.
Therefore, there is not much risk of damaging other blades, and
In the case of the chatter blade, the carbon fibers 3 of the surface layers 2 and 2 of FIG.
Even if it is pulled out from both left and right end faces, that part is shown in Fig. 3.
Since it is often held by the blade support plate 19 shown,
Hard to break.

Further, the carbon fibers 3 of the surface layers 2 and 2 because that is oriented in the sliding direction perpendicular to the direction of the blade, not to damage the other blade or the like.

In the above embodiment, the heating time was lengthened to increase the degree of oxidation of the carbon fibers in the intermediate layer. However, the degree of oxidation of the carbon fibers may be increased by a chemical solution oxidation method using high concentration nitric acid. Further, it may be oxidized by an electrolysis reaction in an acidic electrolytic solution using carbon fiber as an anode.

[0027]

According to the present invention, the degree of oxidation of the carbon fiber of the intermediate layer is made larger than that of the carbon fiber of the surface layer.
The carbon fiber of the intermediate layer can be firmly bonded to the matrix resin, peeling from the lamination boundary surface during shape removal is prevented, and the carbon fiber of the intermediate layer from the end surface parallel to the longitudinal direction of the blade. Is prevented from sticking out and therefore other
It is possible to prevent the blades from being damaged. Furthermore, with shading blades
Then, the rigidity in the longitudinal direction, which is particularly important, becomes high.

[Brief description of drawings]

FIG. 1 is an end face portion (A in the width direction of a light-shielding blade of the present invention).
(Part) is a partial enlarged perspective view of FIG.

FIG. 2 is a plan view of a light shielding blade.

FIG. 3 is a plan view of a focal plane shutter.

[Explanation of symbols]

 1, 15, 16, 17 Shading blade for camera 2 Surface layer 3 Surface layer carbon fiber 4,7 Matrix resin 5 Intermediate layer 6 Intermediate layer carbon fiber

Claims (1)

(57) [Claims] 1. Sliding in a direction substantially perpendicular to the longitudinal direction
In the shading blades, the prepreg sheets in which the carbon fibers are oriented in one direction and impregnated with the matrix resin are laminated, and among the laminated prepreg sheets, the prepreg sheet of the surface layer has an orientation direction of the carbon fibers. In the longitudinal direction of the blade, the prepreg sheet of the intermediate layer sandwiched between the surface layers, the orientation direction of the carbon fibers is the width direction of the blade, the intermediate layer has a degree of oxidation of the carbon fibers than the surface layer. A light-shielding blade for cameras that is large.