JPH09189013A - Manufacture of metallic spherical reflecting mirror and manufacturing device therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently manufacture a spherical reflecting mirror of a good quality at low cost by using a metallic molding plate. SOLUTION: The supplying port 7 of a hydraulic pump 6 is communicated with the molding recessed part 3 of a forming block 5 in which the molding recessed part 3 whose upper end has been opened in a circular form is provided. The opening of this molding recessed part 3 is coated with a protective film 10 consisting of an elastic rubber material. A metallic molding plate 16 is put on the protective film 10 so as to cover the opening of the recessed part 3, and also the peripheral part 17 of the molding plate 16 is pressed against the upper surface of the forming block 5. Thereafter, a prescribed amount of liquid is supplied to the molding recessed part 3 through the hydraulic pump 6, and the part covering the opening out of the molding plate 16 is plastically deformed into a spherical surface by the hydraulic pressure.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a metallic spherical reflecting mirror in which a spherical portion is formed on a metal plate to be molded by using hydraulic pressure.

[0002]

2. Description of the Related Art Metal spherical reflectors are widely used in high-temperature working environments such as road reflectors and blast furnace facilities, taking advantage of their excellent corrosion resistance and heat resistance. The conventional manufacturing method of was as follows. That is, a convex mold b having a convex spherical surface a as shown in FIG.
A pressing die d in which a portion facing the convex spherical surface a is concave (reference numeral c)
As shown in the figure, after placing the metal plate g over the convex die b and the supporting portion (supported by the spring e) f around the convex die b, the pressing die d is placed on the metal plate g. A desired spherical reflecting mirror is made by advancing (falling) toward the convex mold b and plastically deforming the metal plate g so that it finally comes into close contact with the convex spherical surface a as shown in FIG. Was being manufactured.

[0003]

However, the above-mentioned manufacturing method has the following problems. This type of spherical reflecting mirror requires a highly accurate and accurate spherical surface, particularly when it is used as a traffic safety device such as a road reflecting mirror, in view of the fact that an object is correctly viewed. Therefore, it is necessary to finish the convex spherical surface a into a mirror surface with high accuracy, and the manufacturing cost of the mold is enormous. Also, an expensive large press machine is required for the plastic working of the metal plate. Furthermore, during repeated press forming of a large number of metal plates, scratches may occur on the processed surface (convex spherical surface) of the mold, or distortion may occur in the mold itself, but such scratches occur. Then, it appears as a scratch on the product as it is, so it was necessary to correct the mold. If it cannot be corrected, there is a problem that expensive dies need to be replaced and the manufacturing cost of the spherical reflecting mirror increases.

Further, if foreign matter adheres to the machined surface (convex spherical surface) of the mold in the manufacturing process, it will directly damage the product, so that there is a problem in that the manufacturing efficiency is low due to the need for advanced work management.

Further, when using a molding die having a conventional configuration,
Only one mold can manufacture a spherical reflector having one radius of curvature, and there is a disadvantage that an expensive mold is required for each curvature of the spherical reflector.

It is an object of the present invention to provide a method for manufacturing a metallic spherical reflecting mirror, which can solve various problems in the conventional manufacturing method at once. Moreover, it aims at providing the manufacturing apparatus used for it.

[0007]

In order to solve the above-mentioned problems, the present invention employs the following means. That is, a method for manufacturing a metallic spherical reflecting mirror according to the present invention (hereinafter referred to as a manufacturing method)
Uses a molding device in which a supply port of a hydraulic pump is connected to the molding recess of a molding die having a molding recess having a circular opening at the upper end. The board
After being placed on the upper surface of the molding die so as to cover the opening, the peripheral edge portion of the plate to be molded is pressed against the upper surface of the molding die along the edge of the opening, and then, by a hydraulic pump. A predetermined amount of liquid is supplied to the forming recess, and the portion of the plate to be covered that covers the opening is plastically deformed into a spherical surface by the liquid pressure.

A more preferable aspect of the manufacturing method according to the present invention is that the supply port of the hydraulic pump is communicated with the molding recess of a molding die having a molding recess whose upper end is circularly opened. And a molding apparatus in which the opening of the molding recess is covered with a protective film made of a rubber material having elasticity, and the peripheral edge of the protective film is fixed to the peripheral edge of the molding recess. The metal plate to be molded is placed on the protective film so as to cover the opening of the molding recess, and then the peripheral edge portion of the plate to be molded is formed along the edge of the opening. And press it against the upper surface of the mold, and then supply a predetermined amount of liquid to the molding recess from a hydraulic pump, and protect the part of the plate to cover the opening with the hydraulic pressure. The film is characterized by being plastically deformed into a spherical surface while stretching the film.

Further, in the apparatus for manufacturing a metallic spherical reflecting mirror according to the present invention, a supply port of a hydraulic pump is communicated with the molding recess of a molding die having a molding recess whose upper end is circularly opened. The opening of the molding recess is covered with a protective film made of a rubber material having elasticity, and the peripheral edge of the protective film is fixed to the peripheral edge of the molding recess. It is a thing.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 illustrates a manufacturing apparatus used in the manufacturing method of the present invention. The manufacturing apparatus 1 is located at, for example, the central portion of the bottom of a molding die 5 having a molding recess 3 having a circular opening 2 at the upper end, and communicates with a supply port 7 of a hydraulic pump 6 that utilizes hydraulic pressure or water pressure. Let me do it. Further, the upper end opening 2 of the molding recess 3 is covered with a protective film 10 made of a rubber material having elasticity, and an engaging projection 11 is provided continuously along the peripheral edge of the protective film 10. It is secured to the peripheral edge portion 13 of the molding recess 3 via the annular fastening member 12.

In order to manufacture the spherical reflecting mirror 15 as shown in FIG. 2 using the manufacturing apparatus 1, a square plate such as a stainless plate or an aluminum plate is formed so as to cover the upper end opening 2 of the molding recess 3. A metal molded plate 16 (for example, having a thickness of about 1 mm) shown in FIG. 3 and having a circular shape or a circular plate shape is placed on the protective film 10 as shown in FIG. As a result, the plate 16 to be molded and the protective film 10 are brought into close contact with each other. After that, as shown in FIG. 4, the peripheral edge portion 17 of the plate 16 to be molded is formed by the annular pressing tool 19 along the edge 20 of the upper end opening 2 to form the mold 5.
It is pressed against the upper surface 21 of the. Then, the hydraulic pump 6
Then, the liquid (oil or water) 22 is pressure-fed to the molding recess 3. As the liquid is pumped into the molding recess 3, the protective film 1
As 0 extends, the portion 16a of the plate 11 facing the upper end opening 2 is subjected to an evenly distributed load and each part is plastically deformed,
A spherical surface 25 having a desired radius of curvature as shown in FIGS. 2 and 4 is formed.

The radius of curvature of the spherical reflecting mirror can be easily set to a desired value by adjusting the amount of liquid supplied into the molding recess 3.

After the molded plate 16 is plastically deformed into a spherical surface in this way, the product is removed by releasing the pressure applied by the hydraulic pressure. The protective film 10 separates the liquid from the molded plate. Therefore, there is no risk of oil or water adhering to the product surface.

The manufacturing method according to the present invention can be configured without the protective film 10.

[0015]

The present invention has the following excellent effects. According to the manufacturing method of the present invention, after the plate to be molded is placed so as to cover the upper opening of the molding die, a predetermined amount of liquid is supplied to the molding recess from the hydraulic pump, and the free surface is formed. It is possible to apply an evenly distributed load to each part of the plate to be molded while keeping it, which makes it possible to easily and efficiently manufacture a spherical reflecting mirror having an accurate spherical surface with a desired radius of curvature. Therefore, according to the manufacturing method of the present invention, in the conventional manufacturing method in which the quality of the product is affected by scratches on the processed surface of the mold, distortion of the mold itself, or adhesion of foreign matter to the processed surface of the mold. You will be able to solve the problem.

Further, there is an advantage that the radius of curvature of the spherical surface can be easily changed by adjusting the supply amount of the working liquid into the molding recess. Therefore, it is possible to eliminate the uneconomicalness in the conventional manufacturing method, which requires several kinds of molding dies according to the radius of curvature of the spherical reflecting mirror.

The apparatus for manufacturing the spherical reflecting mirror has a simple structure including a molding die having a molding recess and a hydraulic pump for supplying a hydraulic pressure to the molding recess, so that an expensive mold is used. Therefore, the manufacturing cost can be significantly reduced as compared with the conventional manufacturing method that requires a large-sized press machine. Since the indentation liquid is supplied to the forming recess instead of the gas, the metal plate can be curved and deformed according to the amount of the liquid supplied to the forming recess, and it is possible to manage the forming process. Is easy. Further, although high pressure is supplied at the time of molding, unlike the case of supplying gas, there is no danger of destruction and explosion.

When using a manufacturing apparatus having a structure in which the upper end opening of the molding recess is covered with a protective film made of an elastic rubber material, the oil supplied to the molding recess may adhere to the product. In addition, a post-processing step after molding, such as having to wipe off oil etc., becomes unnecessary. Further, the protective film can prevent the supply liquid from being lost due to oil or the like adhering to the product. Therefore, there is no fear that the amount of liquid injected into the molding recess will change, and the spherical reflector with the same accuracy every time. Can be manufactured.

[Brief description of the drawings]

FIG. 1 is a sectional view illustrating a manufacturing apparatus of the present invention.

FIG. 2 is a perspective view illustrating a manufactured spherical reflecting mirror.

FIG. 3 is a perspective view showing a plate to be molded.

FIG. 4 is a cross-sectional view illustrating a manufacturing method of the present invention.

FIG. 5 is a sectional view illustrating a conventional manufacturing apparatus.

FIG. 6 is a cross-sectional view illustrating a conventional manufacturing method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Manufacturing apparatus 2 Opening 3 Recess for molding 5 Mold 6 Liquid pressure pump 7 Supply port 10 Protective film 16 Plate to be molded

Claims (3)

[Claims] 1. A manufacturing method of a metallic spherical reflecting mirror using a molding apparatus in which a hydraulic pump supply port communicates with a molding recess having a molding recess whose upper end is circularly opened. In the method, a metal molding plate is placed on the upper surface of the molding die so as to cover the opening, and then a peripheral edge portion of the molding plate is formed along the edge of the opening. Pressing against the upper surface, and then supplying a predetermined amount of liquid from the hydraulic pump to the molding recess and plastically deforming the part of the plate to cover the opening into a spherical surface by the hydraulic pressure. And a method for manufacturing a metallic spherical reflector. 2. A molding die having a molding recess having a circular opening at the upper end, the supply port of a hydraulic pump communicating with the molding recess, and the opening of the molding recess, A method of manufacturing a metallic spherical reflecting mirror, comprising a molding device which is covered with a protective film made of a rubber material having elasticity, and a peripheral portion of the protective film is fixed to a peripheral portion of a molding recess. After the metal molding plate is placed on the protective film so as to cover the opening of the molding recess, the peripheral edge part of the molding plate is formed along the edge of the opening. After pressing it against the upper surface, a predetermined amount of liquid is supplied from the hydraulic pump to the molding recess, and the liquid pressure causes the protective film to extend to the part of the plate to cover the opening. A method of manufacturing a metallic spherical reflecting mirror, which comprises plastically deforming to a spherical surface. 3. A molding die having a molding recess having a circular opening at the upper end, the supply port of a hydraulic pump communicating with the molding recess, and the opening of the molding recess, An apparatus for manufacturing a metallic spherical reflecting mirror, characterized in that it is covered with a protective film made of an elastic rubber material, and the peripheral edge of the protective film is fixed to the peripheral edge of a molding recess.