JP5041087B1 - Tire vulcanization mold manufacturing method and tire vulcanization mold - Google Patents

Abstract

The present invention relates to a tire vulcanization that facilitates a setting operation of a cylindrical body with respect to a gypsum mold and improves productivity when a cylindrical body embedded in the mold is used to form a mold having a minute gap serving as an exhaust mechanism. A mold manufacturing method and a tire vulcanization mold are provided.
SOLUTION: A cylindrical body 7 formed by opposing the inner peripheral surfaces of both end portions 7b of a plate-like body to a fitting portion 9a of a plate-like fixing metal fitting 9 protruding from the surface of a plaster mold 11 is provided. The opposite end portions 7b are inserted and fitted into the fitting portion 9a, the gap between the opposite end portions 7b is narrowed, and the ends of both end portions 7b are arranged so as to be in contact with the surface of the plaster mold 11. Thereafter, molten metal is poured into the surface of the gypsum mold 11 to embed the cylindrical body 7 in the mold, and the tips of the opposite end portions 7b are exposed to the tire molding surface of the mold, and the fixing bracket 9 is removed from the mold. Thus, a mold in which a minute gap is provided between the opposite end portions 7b is manufactured.
[Selection] Figure 8

Description

  The present invention relates to a method for manufacturing a tire vulcanization mold and a tire vulcanization mold, and more specifically, when a mold having a minute gap that functions as an exhaust mechanism using a cylindrical body embedded in the mold, The present invention relates to a method for manufacturing a tire vulcanization mold and a tire vulcanization mold that can improve productivity by easily setting a cylindrical body on a gypsum mold.

  The tire vulcanization mold is provided with an exhaust mechanism that discharges air remaining between the green tire and the mold or gas generated during vulcanization to the outside of the mold (for example, Patent Documents 1 and 2). reference). Patent Document 1 proposes an exhaust mechanism that uses a laminated blade that bends a thin plate to overlap one end and secures a large gap at the other end. 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.

  Patent Document 2 proposes an exhaust mechanism that uses a cylindrical body embedded during casting of a mold. A slit formed in the outer peripheral surface of the embedded cylindrical body is exposed on the tire molding surface of the mold, and air and gas are discharged to the outside of the mold through this slit. In this proposal, the number of processing steps can be reduced as compared with the proposal in Patent Document 1. However, in order to arrange the cylindrical body at a predetermined position with respect to the gypsum mold, a cylindrical body holding member that is disposed at both ends in the tire circumferential direction of the pieces obtained by subdividing the sector is necessary. Therefore, there has been a problem that the setting work of the cylindrical body becomes complicated with respect to the gypsum mold. Moreover, it is necessary to cast a mold in piece units, and there is a limit to improving productivity.

JP 2008-260135 A JP 2011-46072 A

  It is an object of the present invention to easily perform setting work of a cylindrical body with respect to a gypsum mold when a mold having a minute gap functioning as an exhaust mechanism is used by using the cylindrical body embedded in the mold. An object of the present invention is to provide a tire vulcanization mold manufacturing method and a tire vulcanization mold capable of improving the property.

  In order to achieve the above object, the method for producing a mold for tire vulcanization according to the present invention is a method for producing a tire in which a molten metal is poured onto the surface of a gypsum mold and the molten metal is solidified to produce a mold having the surface of the gypsum mold transferred thereto. In the method for producing a mold for sulfur, a cylindrical body formed by opposing the inner peripheral surfaces of both end portions of a plate-like body to a fitting portion of a plate-like fixing bracket protruding from the surface of a gypsum mold, By inserting and fitting the opposite end portions into the fitting portion, the gap between the opposite end portions is narrowed, and the tips of the both end portions are arranged so as to be in contact with the surface of the plaster mold. Thereafter, the molten metal is poured into the surface of the gypsum mold to embed the cylindrical body in the mold, and the tips of the opposed ends are exposed on the tire molding surface of the mold, and the fixing metal fitting is removed from the mold. And removed by, characterized in that to produce a mold having a small gap between the both end portions are opposed.

  The tire vulcanization mold of the present invention is a tire vulcanization mold formed by solidifying a molten metal. When solidifying the molten metal, a cylindrical body embedded in the mold together with a plate-shaped fixing bracket is provided. The cylindrical body is formed by making the inner peripheral surfaces of both end portions of the plate-like body face each other, and a minute gap is formed between the opposed both end portions, and the minute gap is a mold. It is exposed to the tire molding surface, and the fixing bracket is removed.

  According to the method for manufacturing a tire vulcanization mold of the present invention, the inner peripheral surfaces of both end portions of the plate-like body are opposed to the fitting portions of the plate-like fixing fitting protruding from the surface of the gypsum mold. The opposite end portions of the cylindrical body are inserted and fitted into the fitting portion so that the gap between the opposite end portions is narrowed, and the tips of the opposite end portions of the plaster mold are Since it arrange | positions so that the surface may be touched, the setting operation | work of the cylindrical body with respect to a gypsum mold can be performed easily. Along with this, productivity can be improved. In addition, since the mold can be cast not only in piece units but also in sector units, it is advantageous from this point of view to improve productivity.

  The tire vulcanization mold of the present invention can be obtained by the above production method.

  In the manufacturing method of the present invention, when the opposite end portions of the cylindrical body are inserted into the fitting portion of the fixing bracket, the engaging portion provided in the fitting portion and the opposite end portions The cylindrical body can also be positioned by engaging with an engaging portion provided on the outer peripheral surface. Thereby, a cylindrical body can be set to the predetermined position as set with respect to the gypsum mold.

When the fixing bracket is formed of spring steel, and the cut portion is connected to the lower end of the fitting portion,
It becomes easy to insert the opposite end portions of the cylindrical body into the fitting portion, and it is easy to pull out when removing the fixture from the cast mold.

  When the fixing bracket has an anchor portion that serves as an anchor for the gypsum mold, the fixing bracket can be stably fixed to the gypsum mold.

It is a top view which illustrates the mold for tire vulcanization of the present invention. It is a top view which illustrates the sector of FIG. FIG. 3 is a front view of the sector of FIG. 2. It is a top view which illustrates the left half of the piece of FIG. It is a front view of the piece of FIG. It is an expanded sectional view which illustrates a rubber type which installed a fixture. It is an expanded sectional view which illustrates the process of attaching a cylindrical body to the gypsum mold which installed the fixture. It is an expanded sectional view which illustrates the gypsum mold which installed the cylindrical body via the fixed metal fitting. It is an expanded sectional view which illustrates a cast mold. It is a top view which illustrates the process of pouring a molten metal on the surface of the gypsum mold in which the cylindrical body is arranged in the left half portion of the gypsum mold. It is explanatory drawing which shows the process of FIG. 10 by a front view. It is a top view which illustrates the process of pouring a molten metal on the surface of the gypsum mold corresponding to the sector which has arranged a cylindrical object in the left half part of a gypsum mold. It is a top view which illustrates the sector cast using the gypsum mold of FIG.

  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. C arrow, R arrow, and W arrow described in the drawings indicate a circumferential direction, a radial direction, and a width direction of a green tire that is inserted into a vulcanization mold and vulcanized.

  As illustrated in FIG. 1, a tire vulcanization mold 1 (hereinafter, “mold 1”) of the present invention is a sectional type configured by assembling a plurality of sectors 2 in a ring shape. Each sector 2 includes a plurality of pieces 3 and a back block 4 as illustrated in FIGS. 2 and 3, and is attached to the back block 4 in a state where adjacent pieces 3 are in close contact with each other. The inner peripheral surface of each piece 3 is a tire molding surface 5. The tire molding surface 5 is appropriately provided with a groove molding protrusion 6 for forming a tire groove.

  In this embodiment, four rectangular pieces 3 are fixed to one sector 2 in plan view. The number of pieces 3 included in one sector 2 is not particularly limited, and the arrangement thereof is not limited to this embodiment.

  The piece 3 is formed by solidifying a molten metal M obtained by melting a metal material such as aluminum or an aluminum alloy, and a cylinder embedded when the molten metal M is solidified as illustrated in FIGS. A state body 7 is provided. The cylindrical body 7 extends from one end surface of the piece 3 to the other end surface, and both ends of the cylindrical body 7 are open at both end surfaces in the tire circumferential direction of the piece 3.

  The cylindrical body 7 is formed by making the inner peripheral surfaces of both end portions 7b of the plate-like body face each other, and a slit 8 having a minute gap S is formed between the opposed both end portions 7b. Yes. The slit 8 of the minute gap S is exposed on the tire molding surface 5 of the piece 3.

  For the cylindrical body 7, a metal material whose melting point is higher than that of the molten metal M is used. For example, when the molten metal M is aluminum, a tubular body 7 made of steel such as stainless steel is used.

  In the tubular body 7 of this embodiment, the slit 8 communicates with the hollow interior 7 a having a triangular cross section, and the hollow interior 7 a communicates with the outside of the piece 3 through the slit 8. The slit 8 is formed on the outer peripheral surface of the cylindrical body 7 over the entire length in the longitudinal direction (tire circumferential direction) of the cylindrical body 7 and is exposed on the tire molding surface 5 of the piece 3. The minute gap S of the slit 8 is about 0.01 mm to 0.10 mm, and more preferably about 0.03 mm.

  When the green tire is vulcanized, air and gas are discharged to the inside of the cavity 7a through the slit 8 and further discharged to the outside of the mold 1 through the end face of the sector 2 and the like. Since air and gas that have passed through the slit 8 are discharged into the cavity interior 7a that is much wider than the slit 8, sufficient exhaust can be ensured. Further, by connecting the hollow interiors 7a of the adjacent cylindrical bodies 7 exposed on the end surface in the tire circumferential direction of the piece 3 with exhaust grooves separately formed on the end surface in the tire circumferential direction of the piece 3, the exhaust efficiency is further improved. It becomes possible.

  The slit 8 is provided in a place where air and gas are easily collected when the green tire is vulcanized. For example, the cylindrical body 7 is embedded in the piece 3 (mold 1) so that the slit 8 is disposed in the vicinity of the root portion of the groove forming protrusion 6.

  Since the slits 8 need only be located where exhaust is required, the slits 8 may be provided by embedding the cylindrical body 7 in all the pieces 3 constituting the mold 1, and the cylindrical body is provided only on the specific piece 3. 7 may be embedded to provide the slit 8.

  The cylindrical body 7 is not limited to a triangular cylindrical shape, but may be a cylindrical shape, a cylindrical shape having a rectangular cross-sectional shape, or various cylindrical shapes having other polygonal cross-sectional shapes. The size of the hollow interior 7a of the cylindrical body 7 is, for example, about 0.5 mm to 5.0 mm corresponding to the inner diameter.

  The manufacturing method of this piece 3 is illustrated below.

  First, as illustrated in FIG. 6, a plate-shaped fixing bracket 9 is projected from the surface of the rubber mold 12 to which the surface shape of the master mold is transferred. By pouring gypsum into the surface of the rubber mold 12 in this state and solidifying it, the gypsum mold 11 to which the surface shape of the rubber mold 12 illustrated in FIG. 7 is transferred is manufactured. On the surface of the gypsum mold 11, a fixture 9 is projected.

  The fixture 9 is made of, for example, spring steel and has a thickness of about 0.2 mm to 0.6 mm, preferably about 0.4 mm. The fixing fitting 9 is formed with a fitting portion 9a into which the cylindrical body 7 is fitted. A cut portion 9c having a width narrower than that of the fitting portion 9a is connected to the lower end of the fitting portion 9a (the end in the direction in which the cylindrical body 7 is inserted).

  An anchor portion 9 d that protrudes in the width direction is provided at the lower end portion of the fixture 9. The anchor portion 9d functions as an anchor for the gypsum mold 11. Therefore, the fixing bracket 9 is stably fixed to the gypsum mold 11 by the anchor portion 9d. A through hole may be provided in the fixing metal 9 and the through hole may be used as the anchor portion 9d.

  The fitting portion 9a is provided with an engaging portion 9b that protrudes inward. The engaging portion 9 b engages with a recessed engaging portion 7 c formed on the outer side of the opposite end portions 7 b of the cylindrical body 7. The engaging part 9b may be recessed and the engaging part 7c may be protruded.

  Then, the opposite end portions 7b of the cylindrical body 7 are inserted and fitted into the fitting portions 9a of the fixed mold 9 protruding from the surface of the gypsum mold 11. Thus, as illustrated in FIG. 8, the gap between the opposite end portions 7 b is made narrower than before insertion, and the ends of both end portions 7 b are arranged so as to contact the surface of the gypsum mold 11.

  At this time, the engaging portion 7c and the engaging portion 9b are engaged with each other, and the cylindrical body 7 is positioned and set to the fixing bracket 9 at a predetermined position as installed. When the fixture 9 is made of spring steel and the cut portion 9c is connected to the lower end of the fitting portion 9a, the opposite end portions 7b of the cylindrical body 7 can be easily inserted into the fitting portion 9a.

  The surface 11 a of the plaster mold 11 corresponds to the tire molding surface 5 of the piece 3, and the recess 11 b of the plaster mold 11 corresponds to the groove forming protrusion 6 of the piece 3. Since the surface 11a of the plaster mold 11 has an arc shape in the tire circumferential direction, the cylindrical body 7 may be bent in an arc shape along the arc-shaped surface 11a of the plaster mold 11. When the length of one gypsum mold 11 in the tire circumferential direction is short and the surface 11a is substantially flat in the tire circumferential direction, a linear tubular body 7 can be used.

  Thereafter, as illustrated in FIGS. 10 and 11, the four side surfaces of the gypsum mold 11 are surrounded by the frame member 10, and the molten metal M is poured into the surface 11 a of the gypsum mold 11. When the molten metal M is solidified, as illustrated in FIG. 9, the piece 3 to which the surface 11a of the gypsum mold 11 is transferred is cast.

  Since the tips of the opposite end portions 7b of the cylindrical body 7 are disposed on the surface 11a of the plaster mold 11 so as to be in contact with the surface of the plaster mold 11, the cylindrical body 7 is embedded in the piece 3 together with a part of the fixture 9. The tips (small gaps S) of both end portions 7 b are exposed on the tire molding surface 5 of the piece 3.

  Next, the fixture 9 is removed from the cast piece 3. The narrow hole generated on the surface of the piece 3 by removing the fixing metal 9 is appropriately filled with a metal material having the same quality as the piece 3. If the fixture 9 is made of spring steel and the cut portion 9c is connected to the lower end of the fitting portion 9a, the fixture 9 can be easily pulled out from the cast piece 3.

  As described above, since the setting work of the cylindrical body 7 with respect to the gypsum mold 11 can be easily performed, the work time can be shortened, so that the productivity can be improved.

  In the above embodiment, the case where the sector 2 is composed of a plurality of pieces 3 and is cast by the unit of the piece 2 is exemplified. However, the present invention is not limited thereto, and the present invention can be applied to a case where the sector 2 is not composed of a plurality of pieces 3. . That is, the present invention can also be applied when casting in units of sectors 2.

  In this case, in the same procedure as in the previous embodiment, as illustrated in FIG. 12, the gap between the opposite end portions 7 b of the cylindrical body 7 opposed to each other via the fixing bracket 9 is narrowed. Then, the tips of both end portions 7 b are arranged so as to contact the surface of the gypsum mold 11 corresponding to the sector 2. Thereafter, casting is performed in the same procedure as in the previous embodiment, and the sector 2 illustrated in FIG. 13 is manufactured. In this case, since it is possible to cast in the unit of sector 2 instead of the unit of piece 3 in which sector 2 is subdivided, it is further advantageous to improve productivity.

DESCRIPTION OF SYMBOLS 1 Mold 2 Sector 3 Piece 4 Back block 5 Tire shaping | molding surface 6 Groove shaping | molding protrusion 7 Cylindrical body 7a Cavity inside 7b Butted part 7c Engagement part 8 Slit 9 Fixing metal fitting 9a Fitting part 9b Engagement part 9c Cutting part 9d Anchor Part 10 Frame member 11 Plaster mold 11a Surface 11b Recess 12 Rubber mold M Molten metal

Claims (5)

  In a method for manufacturing a mold for tire vulcanization, in which a molten metal is poured into the surface of a gypsum mold and the molten metal is solidified to produce a mold in which the surface of the gypsum mold is transferred, a plate-like shape protruding from the surface of the gypsum mold By inserting and fitting the opposite end portions of the cylindrical body formed by facing the inner peripheral surfaces of both end portions of the plate-like member to the fitting portion of the fixing metal fitting The gap between the opposite end portions is narrowed and the tips of both end portions are arranged so as to contact the surface of the gypsum mold, and then the molten metal is poured into the surface of the gypsum mold to A mold that is embedded in a mold, the tips of the opposed ends are exposed on the tire molding surface of the mold, the fixing bracket is removed from the mold, and a minute gap is provided between the opposed ends. The Method for producing a tire vulcanizing mold, characterized in that the granulation.   When the opposite end portions of the cylindrical body are inserted into the fitting portion of the fixing bracket, the engagement portion provided in the fitting portion and the engagement provided on the outer peripheral surface of the opposite end portions The method for manufacturing a tire vulcanization mold according to claim 1, wherein the cylindrical body is positioned by engaging the portion.   The method for manufacturing a mold for vulcanizing a tire according to claim 1 or 2, wherein the fixing bracket is made of spring steel, and a cut portion is connected to a lower end of the fitting portion.   The manufacturing method of the mold for tire vulcanization in any one of Claims 1-3 in which the said fixing metal fitting has an anchor part used as an anchor with respect to a gypsum mold.   A tire vulcanization mold formed by solidifying a molten metal has a cylindrical body embedded in the mold together with a plate-shaped fixing bracket when the molten metal is solidified, and the cylindrical body is plate-shaped. It is formed by facing the inner peripheral surfaces of both ends of the body, a minute gap is formed between the opposed ends, and the minute gap is exposed on the tire molding surface of the mold, A mold for tire vulcanization, wherein the fixing bracket is removed.

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