JP2006159596A - Tire mold, plug therefor and tire manufactured using tire mold - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide the vent hole plug of a tire mold constituted so as not only to omit the spew removing work of a tire finishing process but also to enhance the appearance of a product tire while easily performing the cleaning or the like of the mold, and the tire manufactured using this tire mold. <P>SOLUTION: In a holder 4 made of a metal, the through-holes 8a and 8b of a connection pin 6 are formed at the opposed positions of the side surfaces of the exhaust cylinder part 4a of a central part and a flange-like locking part 9 is formed to the bottom part of the exhaust cylinder part 4a while a taper recessed fitting part 10 is formed to the upper part of the exhaust cylinder part 4a. A plug member 5 is constituted by forming a piercing guide hole 11, which has a diameter larger than the diameter (d) of the connection pin 6, to the head part 5a and shaft part 5b fitted to the fitting part 10 and the shaft part 5b of the plug member 5 can always slide through the piercing guide hole 11 up and down along the exhaust cylinder part 4a by the connection pin 6. There is a member 7, which always energizes the plug member 5 in a valve opening direction between the locking part 9 of the holder 4 and the bottom surface of the shaft part 5b of the plug member 5 and, when the tire is inserted in the mold, the head part 5a is closed by the pressure of the tire. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a tire molding die, a plug for a tire molding die, and a tire manufactured using the tire molding die, and more particularly, without generating spew on the tire surface during tire vulcanization molding. The present invention relates to a tire molding die that can be molded and can improve the tire finishing process work and improve the appearance of a product tire, a plug used in a vent hole of the tire molding die, and a tire manufactured using the tire molding die Is.

  Conventionally, a tire molding die used in a tire vulcanization process includes a vent hole in order to exhaust air accumulated between the inner surface of the die and an unvulcanized tire during tire vulcanization molding to the outside of the die. A large number of narrow exhaust holes, which are called, are formed.

  These numerous vent holes are generally machined into areas where mold air is likely to remain. For example, they are machined into 8 or more places on the same circumference of the mold corresponding to bead rings, rims, side portions, etc. The number of circumferential rows varies depending on the tire shape.

  Further, one or more vent holes in the mold design block surrounded by the groove of the tire tread portion are processed (for example, see Patent Document 1).

  However, when a tire is vulcanized and molded with a mold having a large number of vent holes, the vulcanized rubber flows into the large number of vent holes, and a large number of spider-like protrusions (spews) are generated on the surface of the product tire. For this reason, in the tire finishing process after molding the tire, it is indispensable to excise the above spew, which not only hinders workability and productivity, but also a lot of excised spew scraps are scattered to deteriorate the working environment. There was a problem that it was difficult to improve the appearance of the product tire.

  In addition, tire vulcanization molds have been proposed in which each vent hole is provided with a valve configured to close the vent hole during tire vulcanization and open the opening of the vent hole when the tire is released (for example, , See Patent Document 2).

However, the valve used for the vent hole of such a tire vulcanizing mold may adhere to the tire when it is released from the tire, and when the mold is cleaned, the abrasive flows into the valve and the valve operates. There was a problem of being lost.
Japanese Utility Model No.7-33615 microfilm JP 9-141660 A

  This invention has been devised by paying attention to such conventional problems, can be molded without generating spew on the tire surface during tire vulcanization molding, can eliminate the spew removal work of the tire finishing process work, A tire molding die that can improve the working environment, improve the appearance of the product tire, and can easily clean the mold, a plug for the tire molding die, and the tire molding An object of the present invention is to provide a tire manufactured using a mold.

  In order to achieve the above object, the tire molding die according to the present invention is a cylinder in which through holes for connecting pins are formed at opposite positions on the side surface of the exhaust cylinder portion in each vent hole formed in the mold. A metal-shaped metal holder and a slidably fitted to the holder, and a through guide hole for regulating the raised position by the connecting pin is formed, and the valve is always opened through the biasing member. A plug comprising an energized resin plug member is mounted, and the plug member forms a predetermined gap with the holder before inserting the tire into the mold, and the tire pressure after inserting the tire. Thus, the gist of the invention is that the head portion of the plug member is closed to the fitting portion of the holder against the urging force of the urging member.

  The tire molding die plug of the present invention comprises a cylindrical metal holder that is detachably mounted in a vent hole formed in the die, and a resin plug member fitted to the holder. A plug for a tire molding die, wherein the metal holder is formed with a through hole for a connecting pin at a position opposite to a side surface of the exhaust tube portion formed in the center portion and is engaged with a bottom portion of the exhaust tube portion. A stopper is formed, and a tapered concave fitting portion is formed on the upper portion of the exhaust tube portion, and the plug member includes a dish-shaped head portion that fits into the tapered concave fitting portion of the holder, and a shaft portion. A through guide hole having a diameter larger than the diameter of the connecting pin is formed on the base plate, and the plug member is always attached in the valve opening direction between the locking portion formed at the bottom of the holder and the bottom surface of the shaft portion of the plug member. The gist is that the biasing member is interposed. Here, the biasing member uses a spring member or a permanent magnet.

  Further, the tire manufactured using the tire molding die of the present invention has a plug comprising a metal holder in a large number of vent holes formed in the die and a resin plug member fitted to the holder. The gist of the present invention is a tire formed by molding the surface smoothly with a mounted mold.

  In this way, each vent hole formed in the mold is fitted with a cylindrical metal holder in which through holes for connecting pins are formed at opposite positions on the side surface of the exhaust cylinder, and slidably fitted in this holder. At the same time, a through-hole guide hole for restricting the raised position is formed by the connecting pin, and a plug made of a resin plug member that is always urged in the valve opening direction via the urging member is mounted. The plug member forms a predetermined gap with the holder before the tire is inserted into the mold, and the holder is fitted against the urging force of the urging member by the pressure of the tire after the tire is inserted. Since the head part of the plug member is closed at the part, it can be molded without generating spew on the tire surface during tire vulcanization molding, and the spew removal work of the tire finishing process can be omitted, improving the work environment If you can , It is possible to improve the appearance of the product tire.

Since the present invention is configured as described above, the following excellent effects can be obtained. (a) During tire vulcanization molding, molding can be performed without generating spew on the tire surface.
(b) The spew removal work of the tire finishing process can be omitted.
(c) The work environment can be improved because there is little spew scrap.
(d) It is possible to reduce the cost of materials.
(e) The appearance of the product tire can be improved.
(f) When the mold is cleaned, since the bottom surface of the plug composed of the holder and the plug member is opened, no abrasive is deposited in the plug.
(g) When the tire is released from the mold, the plug is not dropped or removed, so that the workability can be improved.

  Embodiments of the present invention will be described below with reference to the accompanying drawings.

  FIG. 1 is a partially enlarged cross-sectional view of a tire molding die in which a valve in an open state is attached to a vent hole formed in a die embodying the present invention, and FIG. 2 is a valve closed state in the vent hole formed in the die. 1 is a partially enlarged cross-sectional view of a tire molding die equipped with a plug of No. 1, 1 is a tire molding die, and 2 is exhausting air accumulated between the die 1 and the tire W during tire vulcanization molding A vent hole 3 formed in the mold 1 for this purpose is a plug composed of a metal holder 4 and a resin plug member 5 mounted in the vent hole 2.

  In this embodiment, each vent hole 2 formed in the mold 1 is formed with a through hole 2a penetrating from the inner surface 1a of the mold 1 to the outside of the mold, and the through hole of each vent hole 2 is formed. 1-4, a cylindrical holder 4 integrally formed of a heat-resistant metal material such as stainless steel or aluminum alloy as shown in FIGS. 1 to 4, and a slide in the exhaust tube portion 4a of the holder 4 Between the plug member 5 integrally formed of a heat-resistant resin material (for example, polytetrafluoroethylene) that is movably fitted and connected by a connecting pin 6, and between the holder 4 and the bottom surface of the plug member 5 A plug 3 comprising an urging member 7 interposed between the two is detachably mounted.

  As shown in FIG. 3, the metal holder 4 is formed with through holes 8a and 8b of the connecting pin 6 at opposite positions on the side surfaces of the exhaust tube portion 4a formed at the center portion. A flange-shaped engaging portion 9 is formed at the bottom of the cylinder portion 4a toward the center, and a tapered concave fitting portion 10 is formed at the upper portion of the exhaust tube portion 4a.

  Further, as shown in FIG. 4, the plug member 5 includes a dish-like head portion 5a that fits into the tapered concave fitting portion 10 of the holder 4, and a shaft portion 5b that has a diameter d of the connecting pin 6. And the shaft portion 5b of the plug member 5 connected via the connecting pin 6 is formed along the exhaust tube portion 4a of the holder 4 with the large diameter through guide hole 11. It is possible to slide in the vertical direction by the space portion.

  Further, an urging member 7 that constantly urges the plug member 5 in the valve opening direction is interposed between the locking portion 9 formed on the bottom of the holder 4 and the bottom surface of the shaft portion 5b of the plug member 5. The urging member 7 includes a spring member 7a such as a coil spring having a predetermined elastic force as shown in FIGS. 1 and 2, or a permanent magnet 7b (N, N, as shown in FIGS. 7 and 8). N or S, S) (for example, a ferrite magnet, preferably an Arconi magnet having a high Curie temperature and a low temperature coefficient, or an iron / chromium / cobalt magnet).

  With this configuration, the plug member 5 and the holder 4 are always connected by the connecting pin 6, and the plug member 5 is formed of the through guide hole 11 having a diameter larger than the diameter d of the connecting pin 6. The space portion is slidable in the vertical direction along the exhaust tube portion 4 a of the holder 4.

  The through guide hole 11 has a diameter larger than the lifting / lowering stroke of the plug member 5 on the outer diameter of the connecting pin 6 or a width larger than the lifting / lowering stroke of the plug member 5 by the width of the diameter of the connecting pin 6. It may be a hole shape (see the chain line in FIG. 4).

  That is, before inserting the tire W into the mold 1, the head portion 5 a of the plug member 5 is caused by the elastic force of the biasing member 7 or the reaction force of the magnetic force, as shown in FIGS. The upper portion of the exhaust cylinder portion 4a is lifted upward from the tapered concave fitting portion 10.

  Thereby, air flows between the tapered concave fitting portion 10 of the metal holder 4 and the dish-like head portion 5a of the plug member 5 during tire vulcanization, but rubber does not flow into 0.02-2.0. A gap H of mm is formed, and the air in the mold passes through the gap H and enters the exhaust cylinder portion 4a through the gap between the holder 4 and the plug member 5, and passes through the through hole 2a below the vent hole 2 to the mold. Exhausted outside.

  When the tire W is inserted into the mold 1, as shown in FIGS. 2, 6, and 8, the dish-like head portion 5 a causes the elastic force of the biasing member 7 due to the pressing force of the tire W. Since it is pressed against the inner side of the exhaust tube portion 4a against the reaction force of the magnetic force, the dish-like head portion 5a is brought into close contact with the taper-like fitting portion 10 of the holder 4, thereby the upper opening of the exhaust tube portion 4a. Close. As a result, the rubber material melted at the time of vulcanization does not flow into the exhaust cylinder portion 4a.

  In this embodiment, the inclination angle α1 of the tapered concave fitting portion 10 is formed around 20 °, but is not limited to this angle, and the tapered concave shape of the plug member 5 is not limited thereto. In this embodiment, the inclination angle α2 of the dish-like head portion 5a fitted to the fitting portion 10 is formed at around 45 °, but is not limited to this angle.

  As described above, when the tire W is molded by the mold 1 in which the plugs 3 each including the metal holder 4 and the resin plug member 5 are mounted in the large number of vent holes 2, as described above, Before the tire is inserted into the mold, air and gas in the mold are exhausted from the lower part of the exhaust cylinder portion 4a of the holder 4 and the plug member 5 to the outside of the mold. After the tire W is inserted, the dish-shaped head portion 5a is brought into close contact with the taper concave fitting portion 10 of the holder 4 due to the pressure of the tire 1 to close the upper opening of the exhaust tube portion 4a. At this time, the vulcanized rubber in a molten state does not flow into the exhaust tube portion 4a or the vent hole 2, and therefore, spew is not generated. Therefore, the surface having a smooth surface as shown in FIG. Tires can be manufactured.

It is a partially expanded sectional view of the tire molding die which attached the plug of the valve-opened state to the vent hole formed in the metal mold | die which implemented this invention. FIG. 3 is a partially enlarged cross-sectional view of a tire molding die in which a valve-closed plug is attached to a vent hole formed in the die. It is an expanded sectional view of the holder in an embodiment of this invention. It is an expanded sectional view of the stopper member in an embodiment of this invention. It is a principal part expanded sectional view which shows the relationship between the holder and tire plug member before tire insertion. It is a principal part expanded sectional view which shows the relationship between the holder and tire plug member after tire insertion. It is an expanded sectional view which shows the relationship between the holder before the tire insertion which shows other embodiment of this invention, and a plug member. It is an expanded sectional view which shows the relationship between the holder after tire insertion which shows other embodiment of this invention, and a plug member. It is a partial perspective view of the tire manufactured with the tire shaping die of this invention.

Explanation of symbols

W Tire 1 Mold 1a Inner surface 2 Vent hole 2a Through hole 3 Plug 4 Holder 4a Exhaust tube 5 Plug member 5a Head 5b Shaft 6 Connecting pin 7 Energizing member 8a, 8b Through hole 9 Locking portion DESCRIPTION OF SYMBOLS 10 Fitting part 11 Through-guide hole 7a Spring member 7b Permanent magnet W Tire H Gap α1, α2 Inclination angle

Claims (4)

In a tire molding die provided with a number of vent holes for exhausting air accumulated between the die and the tire during tire vulcanization molding,
Each vent hole formed in the mold is fitted with a cylindrical metal holder in which through holes for connecting pins are formed at opposing positions on the side surface of the exhaust cylinder, and is slidably fitted to the holder. A plug comprising a resin-made plug member which is formed with a through guide hole for restricting the raised position by the connecting pin and is always urged in the valve opening direction via the urging member is mounted. The member forms a predetermined gap with the holder before inserting the tire into the mold, and after inserting the tire, the member is plugged into the fitting portion of the holder against the urging force of the urging member due to the pressure of the tire. A tire molding die configured to close a head portion of a member. A tire mold plug comprising a cylindrical metal holder detachably mounted in a vent hole formed in a mold and a resin plug member fitted to the holder,
The metal holder is formed with a through hole for a connecting pin at a position opposite to the side surface of the exhaust tube portion formed in the center, and a locking portion at the bottom of the exhaust tube portion. A tapered concave fitting portion is formed in the upper portion, and the plug member has a dish-like head portion that fits into the tapered concave fitting portion of the holder, and a shaft portion having a diameter larger than the diameter of the connecting pin. A through guide hole is formed, and a biasing member that constantly biases the plug member in the valve opening direction is interposed between the locking portion formed at the bottom of the holder and the bottom surface of the shaft portion of the plug member. A plug for a tire molding die. The tire molding die plug according to claim 2, wherein the biasing member is a spring member or a permanent magnet. A mold having a metal holder and a plug made of a resin fitted to the holder in a large number of vent holes formed in the mold according to claim 1 and having a smooth surface for molding. Tires.

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