JPH049052Y2 - - Google Patents

Description

[Detailed description of the invention] [Description of the field to which the invention pertains] The present invention relates to a mold structure, and in particular, the invention relates to a mold structure, and in particular, a sheet material, etc. is fed between a fixed side template and a movable side template, and cut by a mold closing operation. , relates to the structure of a mold for molding a part into a cut part. Furthermore, the present invention particularly relates to a mold structure suitable for the structure of exposure control blades used in cameras and the like.

[Description of conventional technology]

Conventionally, the materials used for exposure control vanes were SK steel,
In 1984, technology was developed in which metal materials such as aluminum and diallumin were press-formed and pins were swaged into punched blades, or resins such as polyester were molded into the shape of the blades, and the pins were crimped or heat-welded. It is known from Publication No.-134023. In recent resin molding techniques, efforts have been made to improve the quality of resin materials, such as making them thinner and improving their flatness and physical strength.

[Purpose of invention]

The present invention involves feeding a sheet-like plate material, such as a metal material or a resin material, to a mold when molding a dowel for controlling a blade (pin) for exposure, and punching out a blade shape from the plate material by closing the mold. The object of the present invention is to obtain a mold structure that can perform cutting and molding of pin parts in the same way by molding a pin directly into the punched cut portion.

[Means for achieving the present invention]

In order to achieve the above-mentioned object, the present invention includes a fixed die, a movable die that is fitted into the fitting portion of the fixed die and is biased by a spring, a fixed side template provided with a sprue on the movable die, a cavity, and an ejector pin. a first movable template fitted with a punch, and a movable side template including a second movable template that is biased by a spring and moves relative to the punch; A workpiece to be cut and molded into an article is inserted between the fixed side template and the movable side template, and the workpiece is cut by a mold closing operation of the movable side template, and the cutting portion is inserted into the movable die and the workpiece. Cutting and article forming, characterized in that the article is held by the punch and is injected into the cavity of the punch through the sprue of the movable die and the cut formed in the workpiece to form the article at the cut portion. The above objective is achieved by proposing a mold structure that performs the following steps.

[Explanation of Examples]

FIG. 1A shows a plan view of an exposure control blade (hereinafter referred to as a blade), and pins (dowels) 2a and 2b for rotating the blade 1 are fixed to the blade 1. A plurality of blades 1 are combined to form an iris diaphragm.

FIG. 1B shows a sectional view taken along the line AA in FIG. 1A.

FIG. 2 shows a mold for forming pins 2a and 2b on the blade 1.

In the figure, 4 indicates a fixed mold plate, and the fixed mold plate 4
are fixed die 4A, movable die 4B, and movable die 4B.
The movable die 4B hits the abutting part 4a ₁ of the fixed die 4A urged by the springs 4C ₁ and 4C ₂ , and _the lower _surface 4b of the movable die 4B is fixed. It maintains the same plane as the lower surface _4a2 of the die 4A. Furthermore, the movable die 4B has sprues 4a ₃ , 4
Set up a ₃ .

Reference numeral 6 indicates a movable template, and the movable template 6 includes a first movable template 6A and a second movable template fitted with the first movable template 6A and urged upward by springs 6B ₁ and 6B ₂ . The second movable template 6C has two movable templates 6C, and the second movable template 6C has a punch 6E that fits into the second movable template 6C and holds ejector pins 6D, 6D.

In the mold open state shown in FIG. 2, the fixed die 4A of the fixed mold plate 4 and the lower planes 4b and 4a ₂ of the movable die 4B
are maintained in the same plane by spring bias.

Furthermore, the first movable template 6A and the second movable template 6C are biased by springs 6B ₁ and 6B ₂ so that the second movable template 6C maintains a predetermined dimension a. At this time, the upper plane 6c ₁ of the second movable template 6C
and the upper plane _6e1 of the punch 6E are kept in the same plane. Cavities 8A, 8B are formed by recesses provided at the upper ends of the ejector pins 6D, 6D and the upper part of the punch 6E into which the ejector pins 6D, 6D fit. Reference numeral 10 shown in FIG. 2 indicates a sheet material made of polyester resin, and the sheet material 10 is inserted between the fixed mold plate 4 and the movable mold plate 6 as shown in FIG. As shown in FIG. 1A, the sheet material 10 has four cuts f ₁ , f 2 , . . . radially from the center of the fixed position of the pins 2 a, ₂ b.
…form f ₄ .

When the mold is opened, the cut portion is moved into the cavity 8 by the feeding means (not shown) of the sheet material 10.
Send it to the center of A and 8B.

After that, the movable mold plate 6 is caused to perform a mold closing operation by a movable means (not shown). When closing the mold, sheet material 10
is the lower plane 4b of the fixed die 4A and the movable die 4B,
4a ₂ , the second movable template 6C, and the upper planes 6c and 6e of the punch 6E.

The second movable template 6C during the above-mentioned pinching operation
The movable die 4B sinks against the springs 6B ₁ and 6B ₂ , and the movable die 4B also sinks against the springs 4C ₁ and 4C ₂ .
By this operation, the sheet material 10 is sheared into the blade shape shown in FIG. 1A by the shearing action of the punch 6E and the second movable template 6C (see FIG. 3).
The sheared blades are held between the movable die 4B and the punch 6E.

In this state, the movable die 4B is attached to the upper fixed mold plate 4A ₁
Connect with the sprue of the upper fixed mold plate 4A ₁ , 4A ₁ −
a, 4A ₁ -b is the sprue 4a ₃ , 4 of the movable die 4B
Connect with a ₃ . In the mold closed state, each cut of blade 1
f ₁ to _{f 4} are located at the center of each cavity 8A, 8B.

When polyester resin is injected into the cavities 8A and 8B from the notches in the blades from an injection cylinder (not shown) through each sprue, the injected polyester resin fills the cavities and is formed into a pin shape, and then undergoes a cooling process. The feather is removed from the mold.

The formed pins 2a and 2b enter into the notches f1 to _f4 of the blade ₁ as shown in the cross-sectional view of FIG. 1B,
The injected polyester resin is melted and fixed to the periphery of the cut portion, and the pins 2a and 2b are fixed to the blade 1.

Note that even when the blades are made of other materials, such as metal, the molten resin adheres to the notched portions of the blades, and the pins are fixed.

[Explanation of effects]

As described above, according to the invention of the present application, manufacturing by injection molding becomes possible, the degree of freedom in pin shape is increased, and costs can be significantly reduced by simultaneous machining of multiple pieces. Furthermore, the performance of the exposure control unit using the blade has been improved due to the reduction in weight. (Improved response characteristics due to lower inertial weight.)

[Brief explanation of the drawing]

FIG. 1A is a plan view of the blade according to the present invention, FIG. 1B is a sectional view taken along the line A-A in FIG. 1A, FIG. The figure is an explanatory diagram of pin forming. 1...Blade, 2a, 2b...Forming pin, 4...
Fixed template, 4B...movable die, 6...movable template,
6E...Punch.

Claims (1)

[Scope of Claim for Utility Model Registration] A fixed die, a movable die that is fitted into the fitting portion of the fixed die and biased by a spring, a fixed side template provided with a sprue on the movable die, a cavity, and an ejector pin. a first movable template into which a punch is fitted; and a second movable template that is biased by a spring and moves relative to the punch; A workpiece to be cut and molded into an article is inserted between the side template and the movable template, the workpiece is cut by a mold closing operation of the movable template, and the cut portion is inserted into the movable die and the punch. and inject resin into the cavity of the punch through the sprue of the movable die and the notch formed in the workpiece to mold the article in the cut portion. Mold structure.