JPS58220130A - Shutter blade - Google Patents

Abstract

PURPOSE:To provide a shutter blade which consists of a thin composite sheet of metal and a plastic having specific stiffness and apparent specific gravity and is light in weight, stiff and thin. CONSTITUTION:A composite body of metal and a plastic having >=10mg/mm.<2> stiffness and <=3.0 apparent specific gravity is used as a shutter blade. The results of tests indicate that, if the stiffness is >=11mg/mm.<2>, the shutter blade is stiff and is therefore free from deformation, and that the leakage of light when a shutter unit is constituted is prevented. If the apparent specific gravity is <=3.0, the shutter curtain ascends quickly and the shutter blade suited for driving by limited power is obtd.

Description

[Detailed description of the invention] The present invention relates to a shutter blade.

Various shutters driven by electromagnetic force have been proposed, but when incorporating such a shutter into a camera, it is difficult to incorporate a large-capacity power supply due to space constraints, so the driving force of the shutter is also limited. It becomes what is given.

Also, even with a shutter that is driven by a spring rather than an electromagnetic drive device, if the camera has a built-in motor hoisting device, the charging torque is limited due to the capacity of the power supply, so sufficient driving force cannot be obtained. In order to achieve a predetermined shutter speed ζ with limited driving force, it is necessary to reduce the weight of the shutter blades and the like.

Particularly in the case of a focal plane shutter that requires opening and closing of seven perchers with a relatively wide area, there is a great need to reduce the weight of the blades.

Various types of glass sheets have been proposed in the past for the purpose of reducing the weight of shutter blades, but the limited thickness does not provide sufficient stiffness and rigidity, resulting in deformation of the shutter blades. ) The defect was that the material leaked from the deformed portion, which made it impossible to put it to practical use.

The object of the present invention is to provide a lightweight, strong, and thin shutter blade that does not have the above-mentioned drawbacks. Therefore, in the present invention, a composite material of metal and plastic having a stiffness of 10 mg/mm or more and an apparent specific gravity of 6.0 or less is used as the shutter blade.

Examples are shown below.

(1) A nickel film having a thickness of 2 μm on each side was formed on a polyester film having a thickness of 50 μm by electroless plating.

(2) J'7. A nickel film with a thickness of 4μ on each side was formed on both sides of a polyester film with a thickness of 50μ by the 8'F plating method.

(6) A nickel film having a thickness of 6 μm on each side was formed on both sides of a polyester film having a N diameter of 50 μm by electroless plating.

(4) Double-sided polyester film with a thickness of 50μ
A 7.5 μm thick nickel film was formed on each side by dt and M nickel plating methods.

(5) A nickel film with a thickness of 4μ on each side was formed on both sides of a polyester film with a thickness of 50μ by electroless plating, and a black lubricating epoxy paint was applied thereon with a thickness of 10μ on each side.

The above-mentioned materials and well-known materials such as the following
・I compared it.

Polyester film H, length 50μ (B) Polyester film J! F, l! 75μ(Cl
A polyester film with a thickness of 50μ and a black lubricating urethane paint coated on each side to a thickness of 10μ. .

Here, the stiffness is determined by the fact that it is close to the actual shutter blade as shown in Fig. 1.10mm5 One end 1b (length 15mm) of the sample 1 with a length of 50mm is fixed to the mounting base 2 shown in Fig. 2 with adhesive 6. and a notch 1 provided at a position 10 mm away from the free end.
Connect a with thin wire 4 and connect it to strain gauge SG,
Stone the resistance (load) when moving platform 2 at a constant speed in the direction of arrow E41 A. It was measured by engagement.

This value indicates that it is thick (・moderately stiff ~・).The apparent specific gravity was determined by measuring the weight in air and water.The shutter speed has the same shape as the well-known metal blade focal plane shutter. A shutter unit is assembled by connecting several shutter blades made in This is a measurement of the time required to travel the road, and the smaller this value, the better.

Detected with a light receiving element.

Table 1 shows the results of the above comparison.

From the above results, if the stiffness is 11 mg/Im'' or more, the shutter blade will be strong and will not be deformed, and if the shutter unit is configured, light leakage will be prevented, and the apparent specific gravity will be 6. If it is less than 0, the shutter speed is high.
It is clear that a shutter blade suitable for driving with limited power can be obtained.

[Brief explanation of drawings]

FIG. 1 is a plan view showing the shape of the sample used to measure the waist strength, and FIG. 2 is a schematic diagram showing the method for measuring the waist strength. 1: Sample, 2: Mounting base, 4: Thin wire, SG: Stone. engagement. Applicant: Canon Co., Ltd. -nσi

Claims (1)

[Claims] Composite of metal and plastic with waist strength of 10mg/m
A camera shutter blade made of a thin plate with a specific gravity of 6.0 m or more and an apparent specific gravity of 6.0 or less.