JPS6313859Y2 - - Google Patents

Description

[Detailed Description of the Invention] Technical Field The present invention relates to a mold for press-bending a metal member such as a trim ring for a wheel cover.

BACKGROUND ART For example, a trim ring R for a wheel cover is made by bending a metal material R' previously formed into a cylindrical shape inward in a direction approximately perpendicular to the middle side using a mold (see Fig. 1 a and b), and applying it to the wheel cover. It is attached to the circumferential edge of the wheel cover C by separately machining the edge of the main body of the cover C and fitting and fixing it (see FIG. 1c).

Conventionally, when inwardly bending this type of metal material R', the step part 1 on which the metal material R' is inserted and placed is
a and a molding surface 1b that is curved in a small radius upward from the vertical surface of the stepped portion 1a, an inner circumferential surface 2a that fits on the outer periphery of the fixed mold 1, and a molding surface 1b of the fixed mold 1. Using a mold consisting of a movable mold 2 having a molding surface 2b having approximately the same curvature as the molding surface 2b, the metal material R' placed on the stepped portion 1a is slightly squeezed from one end edge as the movable mold 2 descends to bend it inward. (See Figure 2). However, with this mold, the tip side drops significantly during bending from one end edge (see Figure 2 b), and is eventually forced to elongate at the bottom dead center of the movable mold 2 to achieve the desired curvature. Although it can be bent and formed (see Fig. 2c), it has the drawback that wrinkles are formed on the outer surface from the inner peripheral edge due to depression during bending, impairing its marketability (see Fig. 3).

DISCLOSURE OF THE INVENTION An object of the present invention is to provide a press-bending mold for a metal member that allows beautiful bending without creating wrinkles on the outer surface.

That is, in the press-bending mold according to the present invention, a receiving mold that is protruded and deflected by a spring is attached to the fixed mold side, and the receiving mold is pushed down and deflected as the movable mold moves downward, so that the movable mold can be moved. The mold side is configured to constantly support the metal material while it is being pressed and bent, so that the metal material can be bent to a desired curvature without pushing the tip side of the metal material.

Embodiment The following will be described with reference to FIGS. 4 to 6.

This molding die includes a fixed die 10 and a movable die 20 that can be moved up and down (see FIG. 4). The fixed mold 10 is composed of a main body 12 forming a step 11 corresponding to the thickness of the metal material R', and a receiving mold 14 having a circumferential side surface 13 regulating the step 11. The main body part 12 is formed so that the inner side of the stepped part 11 is recessed so that the bottom part 15 of the receiving mold 14 is fitted therein. Further, the receiving mold 14 is shaped so that its outer periphery extends beyond the bottom portion 15 to form a circumferential side surface 13 so that it can be locked on the same plane as the stepped portion 11 . The upper edge 16 of this receiving mold 14 is chamfered in a rounded shape from the circumferential side 13 and serves as a forming surface for bending the metal material R'. It is attached by interposing a spring 18 fitted and supported by a support shaft 17 between them. On the other hand, the movable mold 20 has a rising frame portion 22 that protrudes downward from the substrate 21 and receives the main body portion 12 of the fixed mold 10 inside.
and a press die 24 which is attached to the frame portion 22 via a spring 23 so as to be freely deflectable. The rising frame portion 22 has an inner surface that fits into the fixed mold 10 and forms a molding surface for bending the metal material R' between the molding surface of the receiving mold 14. Further, the pressing mold 24 presses and deflects the receiving mold 14, and a notch 25 for receiving the bent tip of the metal material R' is provided in a part of the pressing surface.

This mold is used to mold a trim ring for a wheel cover, and has a fixed mold 10 and a movable mold 20 formed into a planar disk shape. In order to configure the movable mold 20 to be able to move downward horizontally relative to the fixed mold 10, elastic bodies 30, 3 made of urethane resin or the like are formed at regular intervals in the circumferential direction on the plate surface of the fixed mold 10.
0... should be mounted protrudingly. (See Figure 5).

In the mold configured in this way, the cylindrical metal material R' is placed upright on the stepped portion 11 of the fixed mold 10 so as to have a circular planar shape (see Fig. 4), and then the movable mold 20 is lowered. Then, bend the metal material R′ inward from the middle side. When the movable mold 20 descends, the rising frame portion 22 descends while slidingly contacting the circumferential surface of the fixed mold 10, and the inner molding surface gradually bends the metal material R' from the tip side, and the push of the movable mold 20 The mold 24 contacts the receiving mold 14 and deflects the receiving mold 14 downward (see FIG. 6a). When the receiving mold 14 is pressed down by the rising frame portion 22 of the movable mold 20 through the metal material R', the pressing mold 24 presses the receiving mold 14 in synchronization with this, thereby keeping the entire receiving mold 14 horizontal. allows for a descent. The receiving mold 14 always supports the metal material R' from the inside as the movable mold 20 descends, and the metal material R' squeezes the inner edge side between it and the molding surface of the movable mold 20 so that it takes on a substantially inverted L-shape. It can be bent and formed gradually (see Figure 6b). After the bending process,
When the metal material R' moves the movable mold 20 upward and separates from the fixed mold 10, it is attached to the movable mold 20 by reaction force and comes off the mold, so that it can be easily removed. In the above-mentioned embodiment, a cylindrical metal material was pressed and formed to form a trim ring for a wheel cover, but in other cases, for example, a bow-shaped metal material may be bent into a substantially inverted L shape. It is applicable.

Effects of the invention As described above, according to the molding die according to the invention,
Since the metal material is pressed and bent while being supported from the inside at all times, the outer surface of the desired product can be beautifully finished without the occurrence of sagging on the bending tip side that causes wrinkles.

[Brief explanation of the drawing]

Fig. 1a is a perspective view of the metal material, Fig. 1b is a side sectional view of the same metal material in a state where it is bent and formed, Fig. 1c
is a plan view of the same metal material as a trim ring attached to a wheel cover, Figures 2 a to c are explanatory diagrams showing the configuration and operating state of a molding die according to a conventional example, and Figure 3 is an illustration of a conventional example. A partial perspective view of a metal material bent by a mold, FIG. 4 is an explanatory diagram of the configuration of the mold according to the present invention, FIG. 5 is a plan view showing a fixed mold of the same mold, and FIGS. 6 a to c is an explanatory diagram of the operation of the same mold. R': Metal material, 10: Fixed type, 14: Receiving type,
20: Movable mold, 24: Push mold, 30, 30...: Elastic body such as urethane resin.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A metal member is placed upright on a stepped part of a fixed mold, and a movable mold that fits into and lowers the fixed mold is used to place the metal material on the molding surface of the fixed mold located inside. In a mold for inwardly bending the cross section into an inverted L-shape while squeezing the inner edge side by pressing, the molding surface is supported on a fixed mold so that it can be deflected by a spring, and a portion from the upper edge of the metal material to approximately the middle side is used. A mold for bending and forming a metal member, characterized in that the space between the mold and the mold is formed by a receiving mold that moves downward as the movable mold descends. (2) The molding die according to claim 1, wherein the receiving die is configured to be pressed down by a press die mounted inside a movable die so as to be freely deflectable by a spring. (3) The molding die according to claim 1, wherein the movable mold is configured to restrict its downward movement by an elastic body such as urethane resin protruding from the fixed mold.