JP4894522B2 - Manufacturing method of tire mold - Google Patents

Description

  The present invention relates to a method for manufacturing a tire molding die, and more specifically, for tire molding, in which a part of a tire molding die having a three-dimensional blade having an undercut can be easily manufactured by die casting. The present invention relates to a mold manufacturing method.

  In general, a large number of narrow grooves (siping) may be formed on the tread surface of a tire for the purpose of increasing the braking force of the tire and reducing noise. It is formed by a siping blade made of many thin metal materials (for example, stainless steel etc.) embedded in the molding surface.

  For example, as shown in FIGS. 4 and 5, the siping blade is embedded in a base material 1 (gypsum in the case of gypsum casting, or iron or the like in the case of die casting). The sipe molding part 2x of the ping blade 2 is embedded (gypsum is embedded in a gypsum mold, and a groove is formed in the case of a metal mold), and the metal of the tire molding die 3 is embedded in the embedded part 2y of the sipe blade 2 A material (for example, aluminum) is poured and integrally cast.

  After this casting, in order to prevent the siping blade 2 from slipping out of the tire molding die 3 (showing one of the dies divided in the circumferential direction), An anchor hole 4 is formed on the side surface of the embedded portion 2y to allow the molten aluminum to flow as shown in FIG. 6 (a), or at the side edge of the embedded portion 2y as shown in FIG. 6 (b). By forming the undercut portion 5, the metal material of the tire molding die 3 is fixed integrally.

  In addition, when a part (piece) of a tire molding die is injection-molded by conventional die casting, bones and blades forming a tire groove need to be shaped without undercut in the mold opening direction. That is, as shown in FIGS. 7A to 7E, when a part of a tire molding die is injection-molded by a die-casting method, a product blade 7 (siping blade) is previously placed on a mold 6 having a product shape. The product blade 7 is fixed in a state in which the implanted portion 7a is protruded, and the mold 6 is disposed at a predetermined position in the one mother die 8a and the other mother die 8b is clamped. Then, injection molding is performed from the injection molding machine G, and then the molds 8a and 8b are moved in the horizontal direction to open the mold, and the finished product embedded by embedding the implanted portion 7a of the product blade 7 is released. Thus, the finished product W is manufactured.

  In this way, the mother dies 8a and 8b are moved in the horizontal direction to release the finished product W while the mold is opened. Therefore, when the bone or blade forming the tire groove has a three-dimensional shape, the mold is opened. However, when the mold is forcibly opened, the bone and blade part forming the tire groove are damaged, and therefore, there is a problem that only a two-dimensional shape can be used as the shape of the blade.

In addition, a direction in which a part (piece) of a tire molding die using a three-dimensional blade is injection-molded has been proposed (see, for example, Patent Document 1), but the structure for supporting the blade is divided. There is a problem that the structure is complicated and the cost is increased.
JP-A-8-229956

  This invention pays attention to such conventional problems, and when a part of a tire molding die is injection-molded by a die casting method, a part of a die having a three-dimensional blade having an undercut is easily formed by injection molding. An object of the present invention is to provide a method for manufacturing a mold for molding a tire that can be manufactured.

  In order to achieve the above-mentioned object, the present invention fixes a temporary blade in a state in which a blade-planted portion protrudes from a mold having a product shape in advance when a part of a tire molding die is injection-molded by a die casting method. Then, after placing the mold at a predetermined position in the divided mother mold and clamping the mold, injection molding is performed on the product part, and then the mold is opened to release the semi-finished product, The gist is to attach and fix the product blade to the groove portion of the semi-finished product formed by the temporary blade.

  Here, the product blade is a blade having a three-dimensional shape, and when the temporary blade is fixed to the mold, the temporary blade is fixed by a fixing means. Further, when the product blade is mounted and fixed in the groove portion of the semi-finished product, it is fixed through a fixing means.

  By manufacturing in this way, a part of a tire molding die having a three-dimensional blade having an undercut can be easily manufactured by die casting.

  In this invention, when a part of a tire molding die is injection-molded by the die-casting method as described above, the temporary blade is fixed in a state in which the blade implantation portion protrudes from a mold having a product shape in advance, After the mold is placed at a predetermined position in the divided mother mold and clamped, injection molding is performed on the product, and then the mother mold is opened to release the semi-finished product, and then the temporary mold is released. Since the product blade is mounted and fixed in the groove part of the semi-finished product formed by the blade, a part of the mold for tire molding with a three-dimensional blade with undercut, which has been considered difficult in the past, is easily manufactured by die casting In addition, there is an effect that it can be manufactured at a low cost with a simple configuration.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

  Note that the same components as those in the conventional example are denoted by the same reference numerals and description thereof is omitted.

  1 (a) to 1 (g) are explanatory views showing a manufacturing process of a tire molding die according to the present invention. In this manufacturing process, first, a part of a tire molding die is injection molded by a die casting method. In this case, as shown in FIG. 1 (a), the temporary blade 7x is made of a bolt, a pin or the like with the blade implantation portion 7a protruding from a mold 6 (also referred to as nesting) having a product shape (profile) in advance. Fixing is performed by the fixing means 10.

  Then, as shown in FIG. 1 (b), the mold 6 is disposed at a predetermined position in one mother die 8a and the other mother die 8b is clamped, as shown in FIG. 1 (c). Then, injection molding is performed on the product portion 9 from the injection molding machine G. Thereafter, as shown in FIG. 1 (d), the mother dies 8a and 8b are opened to release the semi-finished product Wa, and then the temporary blade 7x is semi-finished as shown in FIG. 1 (e). Pull out from Wa to form the groove 11 in the semi-finished product Wa.

  Then, as shown in FIGS. 1 (f) and 1 (g), a product blade 7 (siping blade) is inserted into the groove 11 of the semi-finished product Wa, and fixing means 12 such as bolts, pins, or adhesives. Is attached and fixed to produce a finished product W that is a part of the tire molding die.

  As the product blade 7, a blade having a three-dimensional shape used in the embodiment of the present invention can be used in addition to a conventional two-dimensional blade, and the semi-finished product Wa is added to the temporary blade 7 x as described above. After forming the groove part 11 in the product blade 7, the product blade 7 is inserted, whereby the product blade 7 of any form can be used regardless of the presence or absence of the undercut.

  2 (a) to 2 (d) are explanatory views of a method of inserting the product blade 7 having a three-dimensional shape into the groove 11 formed in the finished product W and mounting and fixing it by the fixing means 12, and FIG. ) Is a perspective view of a part of a finished product W of a tire molding die to which a product blade 7 having a three-dimensional shape is attached. FIG. 2B is a plan view of the finished product W. FIG. Fig. 2 (b) is a front view as seen from the arrow A-A, Fig. 2 (d) is a side view as seen from the arrow BB of Fig. 2 (c), and Figs. A plan view, a front view, and a side view, attached to a part of a finished product W of a tire molding die to which a product blade 7 having a dimensional shape is attached, are shown.

  In this embodiment, the implanted portion 7a of the product blade 7 is inserted into the groove portion 11 into the semi-finished product Wa formed by the temporary blade 7x, and is formed on the side surface of the finished product W in the through hole 13a formed in the implanted portion 7a. A fixing means 12 such as a pin is inserted from a hole 13b formed in a direction orthogonal to the groove portion 11, and the implanted portion 7a of the product blade 7 is fixed to the groove portion 11 of the finished product W.

  It is also possible to fix with a bolt or the like instead of the pin, and in order to prevent the pin of the fixing means 12 from coming off and to facilitate insertion, as shown in FIGS. 3 (d) and 3 (e). It is also possible to use the pin 14a or the hollow pin 14b. Further, in order to fix the planting part 7a of the product blade 7 to the groove part 11 of the finished product W, a plurality of through holes are formed in the planting part 7a of the product blade 7, and the groove part 11 formed on the side surface of the finished product W; It is also possible to fix by inserting fixing means such as a plurality of pins from a plurality of holes formed in an orthogonal direction.

  As described above, in the present invention, when a part of a tire molding die is injection-molded by the die-casting method, the temporary blade 7x is in a state where the implanted portion 7a of the product blade 7 is protruded from a mold having a product shape in advance. After the mold 6 is disposed at a predetermined position in the mother mold 8a and the mother mold 8b is clamped, the product part 9 is injection-molded, and then the mother molds 8a and 8b are opened. After the semi-finished product Wa is released, the product blade 7 is mounted and fixed in the groove 11 of the semi-finished product Wa formed by the temporary blade 7x, so that it has a three-dimensional blade having an undercut which has been considered difficult conventionally. A part of the tire molding die can be easily manufactured by die casting. Also, the configuration is not complicated and can be manufactured at low cost.

(A)-(g) is explanatory drawing which shows the manufacturing process of the metal mold | die for tire shaping | molding of this invention. (A)-(d) shows explanatory drawing of the method of inserting and fixing the product blade which has a three-dimensional shape in the groove part formed in the finished product, and fixing with a fixing means, (a) has the three-dimensional shape A perspective view of a part of a finished product W of a tire molding die attached with a product blade, (b) is a plan view of the finished product, (c) is a front view taken along the line AA of (b), (d). FIG. 4B is a side view taken along the line BB in FIG. (A) is a plan view attached to a part of a finished product of a tire molding die attached with a product blade 7 having a two-dimensional shape, (b) is a front view taken along the line CC of (a), (C) is the DD arrow side view of (a), (d) is the enlarged front view of the split pin which shows one Embodiment of a pin, (e) is an enlarged front view of a hollow pin. It is explanatory drawing of the method of fixing a siping blade to the conventional metal mold | die for tire molding. It is explanatory drawing of the method of fixing a siping blade to the conventional mold for tire shaping | molding divided | segmented into plurality. (A), (b) is explanatory drawing of the fixing method of the conventional siping blade. (A)-(e) is explanatory drawing which shows the piece manufacturing process in the assembly structure of the conventional mold for tire shaping | molding.

Explanation of symbols

6 Mold 7 Product blade 7a Implanted part 7x Temporary blade 8a, 8b Master mold 9 Product part 10 Fixing means 11 Groove part 12 Fixing means 13a Through hole 13b Hole 14a Split pin 14b Hollow pin G Injection molding machine W Finished product Wa Semi-finished product

Claims (4)

  When a part of a tire molding die is injection-molded by the die casting method, a temporary blade is fixed to a mold having a product shape in a state where the blade implantation part protrudes in advance, and this mold is divided into a master mold. After being placed at a predetermined position in the mold and clamped, the product part is injection-molded, and then the base mold is opened to release the semi-finished product, and then the semi-finished product formed by the temporary blade A method of manufacturing a mold for molding a tire, comprising mounting and fixing a product blade in a groove portion of the tire.   The method for manufacturing a tire molding die according to claim 1, wherein the product blade is a blade having a three-dimensional shape.   The method for manufacturing a mold for molding a tire according to claim 1 or 2, wherein the temporary blade is fixed by a fixing means when the temporary blade is fixed to the mold.   The method for manufacturing a tire molding die according to claim 1, 2 or 3, wherein when the product blade is mounted and fixed in the groove portion of the semi-finished product, the product blade is fixed through fixing means.

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