JP5499929B2 - Tire vulcanization mold manufacturing method and tire vulcanization mold - Google Patents

Description

  The present invention relates to a method for manufacturing a tire vulcanization mold and a tire vulcanization mold. More specifically, the present invention relates to a tire vulcanization mold capable of easily forming an exhaust mechanism capable of ensuring sufficient exhaustion at a required place. The present invention relates to a manufacturing method and a tire vulcanization mold manufactured by the manufacturing method.

  The tire vulcanization mold is provided with an exhaust mechanism that discharges air remaining between the green tire and the mold and gas generated during vulcanization to the outside of the mold. Conventionally, vent holes have been widely used as exhaust mechanisms. However, since rubber flows into the vent holes during vulcanization and spew is generated, various exhaust mechanisms that do not generate spew have been proposed (for example, patents). References 1, 2, 3, 4).

  Patent Document 1 proposes an exhaust mechanism using a laminated blade in which a thin plate is bent to overlap one end and a large gap is secured to the other end in order to ensure sufficient exhaust. The laminated blade is held by a block, and an exhaust chamber surrounded by the pocket and the block is formed by fitting the block into a concave pocket on the molding surface of the mold. Air or gas is discharged into the exhaust chamber through a minute gap at one end of the laminated blade and a large gap at the other end. However, this exhaust mechanism requires a step of forming a pocket on the tire molding surface of the cast mold, a step of manufacturing an assembly in which a laminated blade is held on a block, and a step of fitting this assembly into the pocket. There is a problem in that the number of processing steps increases and the time required for manufacturing becomes long. Further, since a certain amount of space is required to form the pocket, there is a problem that a place where the exhaust mechanism is provided in the mold is restricted.

  In the inventions of Patent Documents 2, 3, and 4, a mold piece is formed by injecting a molten aluminum into the surface of a gypsum mold provided with a shim member such as a thin metal plate and transferring the surface shape of the gypsum mold. The shim member is extracted from the surface of the mold piece to form a slit. An exhaust mechanism is constructed by forming an exhaust hole communicating with the slit in the mold piece. The slit needs to be a very narrow gap in order to discharge unnecessary air and gas to the outside of the mold during vulcanization and to prevent rubber from entering. Along with this, the thickness of the shim member also becomes very thin. Therefore, when the shim member cast into the mold piece is extracted as in the methods of these patent documents, the shim member may be broken, and it is difficult to secure an exhaust mechanism that can secure sufficient exhaust. Met.

JP 2008-260135 A JP 2006-212849 A JP 2009-255303 A Japanese Patent No. 4421473

  An object of the present invention is to provide a method for manufacturing a tire vulcanization mold that can easily form an exhaust mechanism that can secure sufficient exhaust gas at a required place, and a tire vulcanization mold manufactured by the manufacturing method. There is.

  In order to achieve the above object, the tire vulcanization mold manufacturing method of the present invention is a tire for manufacturing a mold in which a molten metal is poured onto the surface of a gypsum mold and the molten metal is solidified to transfer the surface shape of the gypsum mold. In the method for producing a vulcanization mold, a thin metal plate is formed in a cylindrical shape by overlapping both end portions thereof, and a state in which an easily disintegrating refractory material is packed inside a pipe body provided with slits in the overlapped portion. The pipe is placed on the surface of the gypsum mold by inserting a shim protruding from the surface of the gypsum mold into the slit, and then the molten metal is poured into the surface of the gypsum mold to solidify the pipe. The body is cast in a state in which both ends in the pipe axial direction are closed with solidified molten metal, and the mold in which the shim protrudes from the surface is cast. An exhaust hole communicating with the filled-in pipe formed in the mold, thereby removing the easily disintegrable refractory material packed into the pipe through the exhaust hole, characterized in that withdrawing the shim from the slit.

  The tire vulcanization mold of the present invention is a tire vulcanization mold in which the surface shape of the gypsum mold is transferred by solidifying the molten metal poured into the surface of the gypsum mold. The pipe body provided with slits in the overlapped part formed in a cylindrical shape is cast in a state in which the opening in both ends in the pipe axial direction is closed with solidified molten metal and the inside is hollow, The slit is opened in the tire molding surface of the mold, and the hollow interior of the pipe body communicates with an exhaust hole formed in the mold.

  According to the method for manufacturing a mold for vulcanizing a tire of the present invention, a thin metal plate is formed in a cylindrical shape by overlapping both end portions thereof, and the easily disintegratable fireproofing is provided inside the pipe body provided with a slit in the overlapped portion. Since the pipe body is placed on the surface of the gypsum mold by inserting a shim protruding from the surface of the gypsum mold into the slit and filling the material, the pipe body constituting the exhaust mechanism when the mold is completed, Can be easily placed in various places where needed. Then, after arranging the pipe body, the molten metal is poured into the surface of the gypsum mold and solidified, so that the pipe body is cast in a state where the both ends in the pipe axial direction are closed with the solidified molten metal. The mold with the shim projecting from the surface is cast, and then the mold is provided with an exhaust hole communicating with the cast pipe body. By removing the refractory material, the inside of the pipe body is made hollow, and the slit can be opened on the tire molding surface of the mold by pulling out the shim from the slit. Since the shim is inserted into the slit of the pipe body and is not directly cast into the solidified molten metal, it is possible to avoid a problem that the shim is broken when it is pulled out. The slit, the hollow inside of the pipe body, and the exhaust hole form an exhaust mechanism that allows the tire molding surface to communicate with the outside of the mold. That is, according to this manufacturing method, it is possible to obtain the tire vulcanization mold of the present invention provided with an exhaust mechanism capable of ensuring sufficient exhaust at a required place.

  In the method for producing a tire vulcanization mold according to the present invention, the pipe body in this state is made to have a non-filled portion that is not clogged with an easily disintegratable refractory material at both ends of the pipe body in the axial direction of the pipe. It can also be arranged on the surface. When the molten metal is poured into the surface of the gypsum mold, the molten metal enters the unfilled portion, and then the molten metal is solidified in this state. Therefore, even if an external force acts in the direction of closing the slit, the gap of the slit is prevented from being narrowed by the molten metal that has entered and solidified into the non-filling portion. Therefore, it is possible to secure a slit that communicates with the hollow interior of the pipe body.

  It is also possible to have a recess in at least one of both end portions of the thin metal plate, and put both end portions into contact with each other so that the slit is provided by the recess. Alternatively, a large number of shallow grooves can be formed in at least one of both end portions of the metal thin plate. Thus, by providing a recessed part and a shallow groove, even if the both ends of a metal thin plate contact and overlap each other, the hollow inside and exterior of a pipe body can be connected by a recessed part and a shallow groove. That is, it is possible to secure a slit that communicates with the hollow interior of the pipe body by the concave portion or the shallow groove.

It is a top view which expands and illustrates a part of mold for tire vulcanization of the present invention. It is AA sectional drawing of FIG. It is explanatory drawing which illustrates the pipe body filled with the rubber type | mold which protruded the shim on the surface, and the easily disintegrating refractory material. It is explanatory drawing which illustrates the process of pouring a molten metal on the surface of the gypsum mold | die which has arrange | positioned the pipe body. It is explanatory drawing which illustrates the process of extracting a shim from the pipe body cast by the mold which transferred the surface shape of the gypsum mold. It is explanatory drawing which illustrates the process of forming an exhaust hole in a mold. It is explanatory drawing which illustrates the process of removing the easily disintegrating refractory material inside the pipe body cast by the mold. It is sectional drawing which illustrates the constructed exhaust mechanism. FIG. 9A is a front view showing a modification of the pipe body arranged on the surface of the gypsum mold, FIG. 9B is a side view thereof, and FIG. 9C is a plan view thereof. FIG. 10 (a) is a front view showing a modification of the pipe body arranged on the surface of the gypsum mold, FIG. 10 (b) is a side view thereof, and FIG. 10 (c) is a plan view thereof. FIG. 11A is a front view showing a modification of the pipe body, FIG. 11B is a side view thereof, and FIG. 11C is a bottom view thereof. It is a partially notched perspective view which shows the modification of a pipe body.

  Hereinafter, a tire vulcanization mold manufacturing method and a tire vulcanization mold according to the present invention will be described based on the embodiments shown in the drawings.

  As illustrated in FIGS. 1 and 2, the tire vulcanization mold 1 (hereinafter, “mold 1”) of the present invention has a groove forming protrusion 3 and a slit 5 on a tire forming surface 2. The mold 1 is formed by solidifying a molten metal M obtained by melting aluminum or an aluminum alloy. Since the molten metal M poured into the surface of the gypsum mold is solidified and manufactured, the tire molding surface 2 has a shape obtained by transferring the surface shape of the gypsum mold. The slit 5 is appropriately provided at a place where air and gas are easily collected when the green tire is vulcanized.

  In the mold 1, a pipe body 4 in which a metal thin plate is formed in a cylindrical shape by superimposing both end portions thereof is closed with the solidified molten metal at both ends in the pipe axial direction, and the inside is hollow. It is cast. A portion where the thin metal plates of the pipe body 4 are superposed is a slit 5, and one end of the slit 5 is open to the tire molding surface 2. The other end of the slit 5 communicates with the hollow interior 6 of the pipe body 4. An exhaust hole 7 extends from the back side of the mold 1, and the exhaust hole 7 communicates with the hollow interior 6 of the pipe body 4.

  Therefore, unnecessary air and gas for vulcanizing the green tire are discharged from the inside of the mold 1 (the tire molding surface 2 side) to the outside through the exhaust hole 7 through the hollow interior 6 of the pipe body 4 from the slit 5. The In other words, an exhaust mechanism that connects the tire molding surface 2 and the outside of the mold 1 is constructed by the slit 5, the hollow interior 6 of the pipe body 4, and the exhaust hole 7.

  The pipe body 4 is formed by, for example, forming a thin metal plate such as stainless steel having a thickness of 0.01 mm to 3.0 mm into a cylindrical shape. Both ends of the thin sheet metal project linearly from the cylindrical portion of the pipe body 4 to the outer peripheral side, and a portion where the projecting both ends are overlapped with a gap is a slit 5. The pipe body 4 is not limited to a cylindrical shape, and various shapes such as an elliptical shape, a triangular shape, a quadrangular shape, and other polygonal shapes can be adopted as the cross-sectional shape.

  The clearance of the slit 5 is, for example, about 0.001 mm to 0.10 mm, and more preferably about 0.02 mm to 0.05 mm. The depth of the slit 5 is, for example, about 0.1 mm to 10.0 mm. The size of the pipe body 4 is, for example, about 0.5 mm to 5.0 mm corresponding to the inner diameter and about 2 mm to 30 mm in length in the pipe axial direction.

  The method for manufacturing the mold 1 is as follows.

  First, as illustrated in FIG. 3, a shim 8 is protruded from the surface of the rubber mold 9. This rubber mold 9 is manufactured by transferring the surface shape of the master mold.

  In a separate process, the pipe body 4 in which the easily disintegratable refractory material P is packed is manufactured. The easily disintegratable refractory material P is a material that is easily dissolved in a fluid such as water or that is easily disintegrated by impact and has fire resistance. Examples of the easily disintegratable refractory material P include gypsum.

  In order to manufacture the pipe body 4, the easily disintegratable refractory material P is dried by filling the hollow interior 6 with the easily disintegratable refractory material P and then closing both ends of the pipe body 4 with lids or the like. . For example, a dummy shim 11 is inserted into the slit 5 of the pipe body 4 so that the slit 5 is not filled with the easily disintegratable refractory material P.

  Gypsum is poured into the surface of the rubber mold 9 to produce a gypsum mold 10 in which the surface shape of the rubber mold 9 is transferred as illustrated in FIG. The manufactured gypsum mold 10 is in a state in which the shim 8 projecting from the rubber mold 9 is projected.

  Then, the shim 8 protruding from the surface 10 a of the gypsum mold 10 is inserted into the slit 5 from which the dummy shim 11 has been removed, and the pipe body 4 is disposed on the surface 10 a of the gypsum mold 10. The molten metal M is poured into the surface 10a of the gypsum mold 10 and solidified.

  As a result, the pipe body 4 filled with the easily disintegratable refractory material P is cast in a state in which both opening portions in the axial direction of the pipe are closed by the solidified molten metal M, and the shim 8 protrudes from the surface. The provided mold 1 is cast.

  After casting the mold 1, the shim 8 protruding from the surface of the mold 1 is pulled out from the slit 5 as illustrated in FIG. Since the shim 8 is inserted into the slit 5 of the pipe body 4 and directly contacts the solidified molten metal M and is not encased, it is possible to avoid the problem of tearing out when the shim 8 is pulled out.

  Moreover, after casting the mold 1, as illustrated in FIG. 6, the exhaust hole 7 is formed from the back side of the mold 1 using a drilling tool such as a drilling drill 12. A through hole is formed in the cylindrical portion of the pipe body 4 with a drill 12 or the like, and the exhaust hole 7 is communicated with the cast pipe body 4.

  Next, as illustrated in FIG. 7, a high-pressure water flow or the like is injected from the injection nozzle 13 through the exhaust hole 7 to the easily disintegratable refractory material P packed in the pipe body 4. The easily disintegratable refractory material P packed in the pipe body 4 is removed by this high-pressure water flow or the like. By removing the easily disintegratable refractory material P, the inside of the pipe body 4 becomes hollow, and the mold 1 in which the hollow interior 6 of the pipe body 4 communicates with the slit 5 and the exhaust hole 7 as illustrated in FIG. Complete. The shim 8 may be pulled out from the slit 5 after the exhaust hole 7 is formed or after the easily disintegratable refractory material P packed in the pipe body 4 is removed.

  According to the present invention, the pipe body 4 constituting the exhaust mechanism can be arranged at an arbitrary place with respect to the gypsum mold 10 without being severely limited in terms of space. Therefore, the slit 5 can be easily formed at a necessary place of the mold 1. Since the exhaust mechanism for establishing communication between the tire molding surface 2 and the outside of the mold 1 is constructed by the slit 5, the hollow interior 6 of the pipe body 4 and the exhaust hole 7, an exhaust mechanism capable of ensuring sufficient exhaustion at a necessary place is provided. The mold 1 can be obtained.

  When the pipe body 4 is disposed on the surface 10 a of the gypsum mold 10, the tip of the slit 5 can be disposed away from the surface 10 a of the gypsum mold 10 by about 0.5 mm to 2.0 mm. In this case, since the tip of the slit 5 (pipe body 4) is not exposed on the tire molding surface 2 of the cast mold 1, the appearance is improved. In this case, the shim 8 is directly in contact with the solidified molten metal M and cast, but since the directly contacting portion is very small, an excessive resistance such that the shim 8 is shredded when the shim 8 is pulled out. Does not occur.

  As illustrated in FIG. 9, at both ends in the pipe axial direction of the pipe body 4, portions protruding outward in the pipe axial direction are provided, and the protruding portions are formed into unfilled portions 4 a that are not clogged with the easily disintegratable refractory material P. You can also When the molten metal M is poured, the pipe body 4 having the unfilled portion 4 a is disposed on the surface 10 a of the gypsum mold 10. In this embodiment, a through hole 4 b is provided in the cylindrical portion of the pipe body 4. Thus, when the through-hole 4b is previously provided in the pipe body 4, when forming the exhaust hole 7, it is not necessary to form the through-hole 4b in the pipe body 4 using the drill 12 or the like.

  Alternatively, as illustrated in FIG. 10, unfilled portions 4 a can be provided at both ends of the pipe body 4 in the pipe axial direction so as not to simply fill the easily disintegratable refractory material P. When the molten metal M is poured, the pipe body 4 having the unfilled portion 4 a is disposed on the surface 10 a of the gypsum mold 10.

  9 and FIG. 10, after the pipe body 4 provided with the unfilled portion 4a is disposed on the surface 10a of the gypsum mold 10, when the molten metal M is poured, the molten metal M enters the unfilled portion 4a, Thereafter, the molten metal M is solidified in this state. Therefore, even if an external force acts in the direction in which the slit 5 is closed, the gap of the slit 5 is prevented from being narrowed by the molten metal M that has entered and solidified into the unfilled portion 4a. Therefore, a slit 5 communicating with the hollow interior 6 of the pipe body 4 can be secured.

  As illustrated in FIG. 11, a pipe body 4 having a recess 5a on at least one of both end portions of a thin metal plate and overlapping the both end portions in contact with each other to form a slit 5 by the recess 5a is used. You can also

  As illustrated in FIG. 12, a pipe body 4 formed using a thin metal plate having a large number of shallow grooves 5b at at least one of both end portions can also be used. The shallow groove 5b has a groove width of about 0.03 mm to 0.3 mm and a groove depth of about 0.001 mm to 0.3 mm.

  By providing the recess 5a and the shallow groove 5b in this way, even if both ends of the metal thin plate are in contact with each other and overlapped to form the pipe body 4, the hollow interior 6 of the pipe body 4 is formed by the recess 5a and the shallow groove 5b. Can communicate with the outside. That is, the slit 5 communicating with the hollow interior 6 of the pipe body 4 can be secured by the recess 5a and the shallow groove 5b.

DESCRIPTION OF SYMBOLS 1 Mold 2 Tire shaping | molding surface 3 Groove shaping | molding protrusion 4 Pipe body 4a Unfilled part 4b Through-hole 5 Slit 5a Recessed part 5b Shallow groove 6 Hollow inside 7 Exhaust hole 8 Shim 9 Rubber mold 10 Gypsum mold 10a Surface 11 Dummy shim 12 Drilling drill 13 Injection Nozzle P Easily disintegrating refractory material M Molten metal

Claims (5)

  In a method for manufacturing a mold for tire vulcanization, in which a molten metal is poured onto the surface of a gypsum mold, and a mold in which the surface shape of the gypsum mold is transferred by solidifying the molten metal, the metal thin plates are overlapped at both ends. Inside the pipe body formed with a slit in the overlapped part formed in a cylindrical shape, a flammable refractory material is packed, and a shim protruding from the surface of the plaster mold is inserted into the slit. After placing the pipe body on the surface of the gypsum mold, the molten metal is poured into the surface of the gypsum mold and solidified, thereby closing the pipe body with the molten metal solidified at both ends in the pipe axial direction. And casting a mold in which the shim projects from the surface, and then forming an exhaust hole in the mold to communicate with the cast pipe body. Easy to remove the decay refractory materials, manufacturing method of the tire vulcanizing mold has been characterized by withdrawing the shim from slit packed into the pipe through.   2. The tire additive according to claim 1, wherein the pipe body is arranged on the surface of the gypsum mold in a state in which the pipe body has an unfilled portion that is not clogged with an easily disintegratable refractory material at both ends in the pipe axial direction. A method for producing a mold for sulfur.   The mold for tire vulcanization according to claim 1 or 2, wherein a concave portion is provided in at least one of both end portions of the thin metal plate, the both end portions are brought into contact with each other, and the slit is provided by the concave portion. Manufacturing method.   The method for producing a tire vulcanization mold according to claim 1 or 2, wherein a number of shallow grooves are formed in at least one of both ends of the metal thin plate.   In a tire vulcanization mold that transfers the surface shape of the gypsum mold by solidifying the molten metal that has flowed into the surface of the gypsum mold, the metal thin plates are overlapped at both ends to form a cylinder The pipe body provided with slits in the pipe is closed with the molten metal solidified at both ends in the axial direction of the pipe and cast in a hollow state, and the slits open on the tire molding surface of the mold. A tire vulcanization mold, wherein a hollow interior of the pipe body communicates with an exhaust hole formed in the mold.

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