JPH04208412A - Manufacture of mold - Google Patents

Abstract

PURPOSE:To easily and surely manufacture a mold by a method wherein resin layer having the predetermined thickness is formed on a metal base plate and, after that, the resin is machined so as to produce pattern part. CONSTITUTION:At splits mold for tire, a tread segment 5 is peripherally multiply-divided. And, on the inner surface of the segment 5, tread pattern- forming projections 6 are integrally formed. In order to manufacture the mold concerned, firstly, necessary number of base plates 1 having no pattern thereon are manufactured or concretely the segment 5 is vertically bisected at the equator E-E of the mold and, at the same time, the mold base plates or segment base plates, each of which has no projection 6 thereon, are produced. Next, on each base plate 1 (or on each inner surface 3), resin layer 4 having the predetermined thickness is formed. After that, the resin layer 4 is cut with a machine tool or the like so as to form the pattern part 2 having the desired shape in order to finish up the base plate having pattern thereon. By combining the necessary number of the finished patterned base plates with one another, one mold (such as an annular tread-patterned mold) is obtained. Thus, a mold having complicatedly shaped pattern part 2 can be manufactured simply and quickly at a low cost.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a mold manufacturing method.

[Prior art and problems to be solved by the invention] Conventionally, there are the following two methods for manufacturing a mold.

■ First, use wax, plaster, etc. to make a mold of the item you want to manufacture (
For example, a mold for a rubber product such as a tire is created, metal such as aluminum or iron molten at high temperature is poured into the outside of this mold, and after cooling, the mold made of the wax, plaster, etc. inside is removed. to manufacture molds.

■ Manufacture a lump of metal such as aluminum or iron, and add N to it.
A mold with the desired shape is manufactured by cutting using a machine tool such as a C-machine.

By the way, recently, patterns on molds have become more complex and detailed, such as tire tread patterns.
The above-mentioned method (■■) requires extremely advanced technology and skill, and is difficult to manufacture quickly and reliably. In addition, especially method (2) requires the use of machine tools, resulting in high costs, complicated processes, and a long production lead time.

Therefore, an object of the present invention is to provide a mold manufacturing method that can easily and reliably manufacture a mold.

[Means to solve the problem]

In order to achieve the above object, the mold manufacturing method according to the present invention includes forming a resin layer of a predetermined thickness on a metal substrate, and then
The pattern portion is formed by cutting the resin layer.

[For production]

Since the resin layer is cut without cutting the metal substrate, the processing can be easily performed with a simple machine tool, and even complex-shaped patterns can be easily formed. I can do it.

〔Example〕

EMBODIMENT OF THE INVENTION Hereinafter, the present invention will be explained in detail based on drawings showing examples of tire molds.

FIG. 2 is a left half cross-sectional view of a conventional split mold for tires, in which 5 is a tread segment which is divided into multiple parts in the circumferential direction, and a projection 6 for forming a tread pattern is integrally formed on the inner surface of the segment 5. There is. 7 is a side plate, 8 is a sector, 9 is an actuator, and IO is a platen.

FIG. 1 shows the manufacturing process of the mold manufacturing method according to the present invention,
The mold manufactured by this method, as shown in FIG. 1 (n , consists of.

That is, in order to manufacture this mold, first, as shown in FIG. 1(1), a required number of substrates 1 without a pattern are manufactured. That is, each tread segment 5 shown in FIG. 2 is divided into upper and lower halves at the equator E-E of the mold, and a mold substrate or segment substrate without the protrusion 6 is manufactured. Since this substrate 1 is a plane without any protrusions (patterns), cost and delivery time can be significantly reduced compared to conventional segments.

Next, on each substrate 1 (specifically, the inner surface 3) as shown in FIG.
As shown in n), a resin layer 4 having a predetermined thickness is formed. A known resin is used, but one with good heat resistance and thermal conductivity is used, and the predetermined wall thickness may be one that fits the pattern that will be added later, for example, about 10 cm. do. In other words, the wall thickness should be about the maximum thickness of the pattern part 2, and if it is a mold for manufacturing passenger car tires, for example,
The length should be about 20 m, and if it is a mold for manufacturing tires for large vehicles, it should be about 10 to 50 m.

Thereafter, the patterned substrate is completed by cutting the resin layer 4 using a machine tool or the like to form the patterned portion 2 in a desired shape as shown in FIG. 1 (II[). A required number of completed patterned substrates are combined together to form one mold (for example, an annular tread pattern mold).

Therefore, the durability of the mold formed as described above is inferior to that of the conventional mold made entirely of metal, but in recent years, in the production of a wide variety of products in small quantities, it is cheaper and faster to manufacture than the durability. However, it is far more advantageous to have a material that can be easily patterned with various patterns.
The manufacturing method as described above is extremely effective. In addition, the parts of the manufactured mold that require strength and durability as a mold (
In other words, since the substrate 1) is made of metal and the rest (that is, the patterned portion 2) is made of resin, it can be fully used as a mold.

Note that the present invention is not limited to the above-described embodiments, and the design may be changed without departing from the gist of the present invention. For example, the size, shape, etc. of the substrate 1 may be changed depending on the article to be vulcanized. The substrate 1 can be made of various materials, and various metals such as aluminum and steel can be used as the material of the substrate 1. Further, the pattern of the pattern portion 2 is not limited to the turned pattern, and may have various shapes.

[Effects of the Invention] Since the present invention is configured as described above, it produces the following effects.

Compared to the conventional method of cutting metal, it is possible to use a simple and inexpensive machine tool, and it is possible to manufacture a mold having a pattern part 2 of a complicated shape easily, quickly, and at low cost. can. Specifically, both the manufacturing time and cost were reduced to about 1/10.

In addition, it does not require advanced technology or skill, and although it is less durable than a mold made entirely of metal,
Since the parts that require strength and durability as a mold are made of metal, it can be used satisfactorily as a mold.

[Brief explanation of the drawing]

FIG. 1 is a simplified perspective view showing one embodiment of the present invention. FIG. 2 is a partial sectional view of a conventional tire split mold. 1... Metal substrate, 2... Pattern portion, 4... Resin layer. Ward 2-671

Claims (1)

[Claims] 1. A mold manufacturing method, which comprises forming a resin layer 4 of a predetermined thickness on a metal substrate 1, and then cutting the resin layer 4 to form a patterned portion 2.