JP2552649Y2 - 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 light-shielding blade for a camera, and more specifically, to a light-shielding blade required to move at a high speed, such as a focal plane shutter of a camera, a shutter blade of a lens shutter or an aperture blade. About.

[0002]

2. Description of the Related Art Shutter speed has been increased in order to increase the photographing area of a focal plane shutter, for example. However, with a structure of a light-shielding blade using a duralumin plate, there is a limit to thinning in order to maintain rigidity. 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.

[0003] Conventionally, a blade structure using a carbon fiber reinforced thermosetting resin sheet is formed by laminating a plurality of unidirectional reinforced prepregs in which carbon fibers are arranged in one direction with the carbon fiber directions orthogonal to each other. It has a structure solidified by hot pressing (Japanese Utility Model Application Laid-Open No. 60-63825, Japanese Utility Model Application Laid-open No.
65726).

[0004]

Therefore, there is a problem that the laminating and pressing steps are required, and the number of steps is increased.

Further, there is a problem that the adhesion between the laminated and pressed prepreg sheets cannot be maintained, and the sheets are peeled off during use or the like.

Accordingly, an object of the present invention is to provide a light shielding blade for a camera which can omit a laminating step and does not cause a problem of peeling between laminated sheets.

[0007]

In order to achieve the above-mentioned object, a camera light-shielding vane according to the present invention comprises a carbon fiber arranged along a longitudinal direction and a carbon fiber arranged along a width direction. The fabric is formed into a single fabric, and the fabric is formed of a sheet fixed by a matrix resin.

[0008] The amount of carbon fibers in the longitudinal direction is preferably larger than the amount of carbon fibers in the width direction.

Further, a lubricating paint is preferably applied to the surface of the sheet.

[0010]

[Function] The carbon fiber arranged along the longitudinal direction and the carbon fiber arranged along the width direction are woven into a single woven fabric, which is fixed with a matrix resin to form a sheet. Since the direction of the carbon fiber is defined as the longitudinal direction and the width direction of the blade, the carbon fiber is oriented in a direction requiring rigidity.

Further, by making the amount of carbon fibers in the longitudinal direction larger than the amount of carbon fibers in the width direction, the required rigidity in the longitudinal direction, which is more rigid, is sufficiently enhanced, and a light-shielding blade with higher rigidity can be obtained.

Further, by applying a lubricating paint to the surface of the sheet, slidability and light-shielding properties are improved.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One 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-shielding blade 1.
FIG. 1A is an enlarged plan view and FIG.
This is shown in (B).

As shown in FIGS. 1 (A) and 1 (B),
A plurality of weft yarns 2 made of 10 μm carbon fiber and a plurality of warp yarns 3 made of carbon fiber are woven so as to be substantially orthogonal to each other to form a woven fabric 5. The weft 2 corresponds to the longitudinal direction of the light-shielding blade 1, and the number of the wefts 2 per unit length is larger than the number of the warps 3 in the unit length. This is because the light-shielding blades are more likely to bend in the longitudinal direction than in the width direction of the light-shielding blades, so that a greater rigidity is required in the longitudinal direction of the light-shielding blades to prevent this. Therefore, the ratio between the number of the weft yarns 2 and the number of the warp yarns 3 in the unit length is determined so as to correspond to the rigidity required in the longitudinal direction and the rigidity required in the width direction. The thickness of the woven fabric 5 in which bidirectional carbon fibers are woven is 70 to 80 μm.

Next, as shown in FIG. 1B, the woven fabric 5 is impregnated with a matrix resin 6 made of a thermosetting resin such as epoxy or unsaturated polyester. Therefore, the bidirectional carbon fibers 2 and 3 are fixed in the matrix resin 6, so that the bidirectional carbon fibers 2 and 3 are fixed to each other via the matrix resin 6.

Then, on both surfaces of the matrix resin 6,
A lubricating paint 8 made of a solid lubricant such as molybdenum disulfide or fluorine mixed with carbon black and a black pigment is applied. The thickness of the sheet containing the lubricating paint 8 is within about 100 μm.

The light-shielding blade for a camera constructed as described above is manufactured by first weaving a weft yarn 2 and a warp yarn 3 into a predetermined size to form a woven fabric 5, impregnating the woven fabric 5 with a matrix resin 6, After forming a prepreg sheet in a stage state (intermediate cured state), the prepreg sheet is pressed by a hot press,
Heat and cure, fiber reinforced plastic (FRP)
Sheet 7 is assumed. Then, the respective directions of the weft yarn 2 and the warp yarn 3 are aligned with the longitudinal direction and the width direction of the blade, the shape is cut out in the shape of a light shielding blade for a camera, and then the lubricating paint 8 is applied to the surface of the blade. The blade 1 is completed. According to the present invention, the step of stacking sheets is not required, and the manufacturing process of the blade is simplified.

The blade 1 formed as described above 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
11 is attached. These arms 9, 10, 11
Is attached to the blade receiving plate 19, and the opening 19a is closed to form a shutter. When the rotating portion 18 is rotated by a predetermined means, the blade 1,
The shutters 15, 16, 17 move in parallel to open and close the shutter. Here, since the blades 1, 15, 16, 17 are lightweight, the shutter speed can be increased. In addition, since carbon fibers are woven, strong rigidity is obtained, and the blade is prevented from bending. Since the lubricating paint 8 is applied to the surface of the blade, slidability and light-shielding properties are ensured. Also, because carbon fiber is woven,
Peeling does not occur between carbon fibers in two directions.

In the above embodiment, the lubricating paint is applied to both sides of the matrix resin, but may be applied to only one side.

[0021]

According to the present invention, the step of laminating the sheets becomes unnecessary, the manufacturing process is simplified, and the fibers are woven in two directions, so that the fibers do not peel off in the two directions.
Further, since the sheets are not stacked, variations in the thickness of the blades are reduced. By increasing the number of weft yarns and decreasing the number of warp yarns, the required rigidity of the light-shielding blade is ensured, the weight of the blade is reduced, and high-speed driving is possible.

[Brief description of the drawings]

1A is a partially enlarged plan view of a light shielding blade, and FIG. 1B is a partially enlarged sectional view of a light shielding blade.

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 Weft 3 Warp 5 Fabric 6 Matrix resin 7 Sheet 8 Lubricant paint

Claims (3)

(57) [Scope of request for utility model registration] 1. A single woven fabric is formed by weaving carbon fibers arranged along the longitudinal direction and carbon fibers arranged along the width direction, and the woven fabric is fixed by a matrix resin. A light-shielding blade for a camera, wherein the light-shielding blade is formed of a sheet. 2. The light shielding blade for a camera according to claim 1, wherein the amount of carbon fibers in the longitudinal direction is larger than the amount of carbon fibers in the width direction. 3. The camera light-shielding vane according to claim 1, wherein a lubricating paint is applied to a surface of the sheet.