JP2008238779A - Method and device for vulcanizing tire - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent the occurrence of burrs while suppressing variations in rubber weight of a vulcanized tire. <P>SOLUTION: Each recess 61 is provided on the external surface of a rigid-body core 30 while each space 62 is formed on a deeper side than the recess 61 in the rigid-body core 30. On the other hand, the recess 61 and the space 62 are made to communicate with each other by a fine passage 63. Therefore, during the closure of an external mold for vulcanization or during the vulcanization, excessive rubber of an unvulcanized tire flows into the recess 61, the fine passage 63, and the space 62 in that order so as to be discharged from inside a vulcanizing space. As a result, it prevents the occurrence of burrs by the suppression of an excessive pressure increase inside the vulcanizing space. When taking out the rigid-body core 30 from inside the vulcanized tire, excessive rubber is cut inside the fine passage 63. Thus, it suppresses variations in rubber weight of a vulcanized tire. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

    The present invention relates to a tire vulcanization method and apparatus for vulcanizing an unvulcanized tire housed in a vulcanization space between an outer mold and an inner mold.

    In recent years, an unvulcanized tire is formed by braiding or winding tire constituent members such as rubberized cords or belt-shaped rubber around a rigid inner mold, and then both the inner mold and the unvulcanized tire are formed in the outer mold. There has been proposed a tire vulcanizing method and apparatus that are accommodated in a vulcanized vulcanized container. Here, in such a vulcanizing method and apparatus, the volume of the unvulcanized tire is usually set to a value slightly larger than the volume of the vulcanized space, and the inner mold and unvulcanized Since the vulcanized tire is thermally expanded, the pressure in the vulcanization space rises when the outer mold is closed or when the tire is vulcanized, and excess unvulcanized rubber protrudes between the core segments constituting the inner mold, causing burrs. It has occurred.

Therefore, in order to suppress the occurrence of such burrs, for example, a tire vulcanizing method and apparatus as described in Patent Document 1 below have been proposed.
JP 2006-56066 A

  This is an outer mold that can mold the outer surface of an unvulcanized tire, and a donut that can be molded on the inner surface of an unvulcanized tire by forming a large number of cylindrical recesses on the outer surface. A deformed space surrounded by the dent and the bottom surface of the dent is formed in the inner mold by storing the elastic plug in the dent. It is.

  When the outer mold is closed or vulcanized, the elastic plug pushed by the unvulcanized tire deforms to dent inward while squeezing the deformation space, so that the rubber escape space (the vulcanization space This increases the pressure in the vulcanization space and suppresses the generation of burrs.

    However, in such a conventional tire vulcanizing method and apparatus, all of the excess unvulcanized rubber obtained by subtracting the volume of the vulcanized space from the maximum volume of the unvulcanized tire does not protrude from the elastic plug. Since the fluid flows (inflows) into the escape space generated by the deformation, when the vulcanization is completed with the elastic plug being deformed as described above, the rubber is placed on the inner surface of the vulcanized tire at a position corresponding to the elastic plug. Large protrusions were formed, respectively. As a result, there was a problem that local variation occurred in the rubber weight of the vulcanized tire and the uniformity was deteriorated.

  An object of the present invention is to provide a tire vulcanizing method and apparatus capable of preventing the occurrence of burrs while suppressing variations in rubber weight in vulcanized tires.

    The purpose of this is, firstly, a recess is provided on the outer surface, a space is formed on the back side of the recess, and an inner mold and an outer mold having a donut shape in which the recess and the space communicate with each other through a narrow passage. The step of storing the unvulcanized tire in the vulcanized space between the mold and the vulcanized tire is vulcanized, and the outer surface of the unvulcanized tire is molded with the outer mold, while the inner surface is molded with the inner mold. And a tire vulcanization method in which excess rubber of the unvulcanized tire is recessed during the vulcanization, and is allowed to flow into the narrow passage and space in the order described above, and can be achieved,

  Secondly, an outer mold that can mold the outer surface of the unvulcanized tire and an inner mold that has a donut shape that can mold the inner surface of the unvulcanized tire, and between the outer mold and the inner mold In a tire vulcanizing apparatus for vulcanizing an unvulcanized tire housed in a vulcanized space, a recess is provided on the outer surface of the inner mold, and a space is formed in the inner mold on the back side of the recess. On the other hand, it is achieved by a tire vulcanizing device in which the recess and the space are communicated by a narrow passage, and excess rubber of the unvulcanized tire is recessed at the time of vulcanization and flows into the narrow passage and the space in the order described above. can do.

  In the present invention, a recess is provided on the outer surface of the inner mold, and a space is formed in the inner mold on the back side of the recess. On the other hand, the recess and the space are communicated by a narrow passage. Alternatively, when the pressure in the vulcanized space increases during vulcanization, excess unvulcanized rubber, which is obtained by subtracting the volume of the vulcanized space from the volume of the unvulcanized tire due to the increased pressure, is recessed from the vulcanized space, It flows into the passage and space in the above order and is discharged from the vulcanization space. And when excessive rubber | gum is actively discharged | emitted from a vulcanization space in this way, the excessive pressure rise in the said vulcanization space will be suppressed, and generation | occurrence | production of a burr | flash can be prevented effectively.

  Further, when the inner mold is taken out from the vulcanized tire after the vulcanization as described above is finished, the rubber in the narrow passage is pulled and cut, so that most of the excess rubber is the inner narrow passage. On the other hand, on the inner surface of the vulcanized tire, only the hollow rubber of the excess rubber remains as protrusions on the inner surface of the vulcanized tire. And uniformity can be improved.

  According to the third aspect of the present invention, a part of the excess rubber remains as a protrusion (protrusion) extending in the circumferential direction on the inner surface of the vulcanized tire. Therefore, the tire corresponding to the protrusion In addition to providing a cutting means such as a cutter at the position in the width direction, the protrusions can be removed simply by rotating the vulcanized tire, thereby making it easy to remove excess rubber. In addition, the number of depressions to be formed can be reduced as compared with a cylindrical depression, the structure is simplified, and the production cost can be reduced.

  Furthermore, if it comprises as described in Claim 4, the inner type | mold in which the hollow, the narrow channel | path, and the space were formed can be manufactured easily, and manufacturing cost can also be made cheap. Further, when configured as described in claim 5, the rubber constituting the tire flows into the narrow passage and the space and prevents a situation in which the amount of tire rubber is insufficient, and excess rubber is removed. The narrow passage can surely flow into the space, and the rubber in the narrow passage can be made thin enough to be easily cut simply by taking out the inner mold from the vulcanized tire.

  Furthermore, if it comprises as described in Claim 6, the excess rubber | gum into a narrow channel | path and space can be made to flow reliably and fully. According to the seventh aspect of the present invention, when the inner mold is taken out from the vulcanized tire, it is possible to prevent the molding block from coming out of the storage groove. Can be cut off. Furthermore, if constituted as described in claims 8 and 9, it is possible to reliably prevent the molded block from coming out of the storage groove while being simple in structure and easy to manufacture. Moreover, if comprised as described in Claim 10, an excess rubber | gum can be smoothly guide | induced to a narrow channel | path and space.

Embodiment 1 of the present invention will be described below with reference to the drawings.
In FIG. 1, 11 is a tire vulcanizer, and this tire vulcanizer 11 has a lower base 12 on which a high-temperature and high-pressure vulcanization medium is supplied inside during vulcanization. The lower platen 13 is fixed, and a lower mold 14 for attaching a lower side wall portion E and a lower bead portion B to be described later is mounted on the lower platen 13.

  15 is an upper base installed above the lower base 12, and an upper platen 16 similar to the lower platen 13 is fixed to the lower surface, and the upper base 15 is raised and lowered by a cylinder (not shown) Approach and leave the lower base 12. An upper plate 21 connected to the tip of a piston rod 20 of a cylinder (not shown) is installed directly below the upper base 15, and the upper plate 21 is moved up and down separately from the upper base 15 by the operation of the cylinder. can do.

  22 is an upper mold that is fixed to the lower surface of the upper plate 21 and moves up and down together with the upper plate 21 so as to approach and separate from the lower mold 14, and this upper mold 22 is made of unvulcanized tires during vulcanization. The upper sidewall portion E and the upper bead portion B are molded. An outer ring 23 is provided so as to surround the upper plate 21 from the outside in the radial direction, and the upper end of the outer ring 23 is fixed to the upper base 15. The inner periphery 23a of the outer ring 23 is an inclined surface (a part of a conical surface) that expands downward.

  24 is a plurality of arcuate holders arranged side by side in the circumferential direction. These holders 24 are supported by the upper plate 21 so as to be movable in the radial direction, and vulcanized inside during vulcanization. Medium is supplied. Further, arc-shaped sector molds 25 are attached to the inner periphery of each holder 24, and these sector molds 25 mold the shoulder portion S and the tread portion T of the unvulcanized tire during vulcanization.

  An inclined surface (a part of a conical surface) having the same gradient as the inner periphery 23a of the outer ring 23 is formed on the outer periphery 24a of each holder 24. The inner periphery 23a and the outer periphery 24a are slid while being connected by a joint. It is movably engaged. As a result, when the outer ring 23 moves up and down with respect to the upper plate 21, the holder 24 and the sector mold 25 move in synchronization with the radial direction while being supported by the upper plate 21.

  The above-described holder 24 and sector mold 25 constitute a sector mold 26 as a whole, and the lower, upper molds 14, 22 and sector mold 26 as a whole mold the outer surface (outer surface) of the unvulcanized tire. A vulcanized outer mold 27 is configured as an outer mold that can be used. In this embodiment, the outer vulcanization mold may be divided into two parts and may be composed of an upper mold.

  In FIGS. 1, 2, and 3, 30 is a rigid core as an inner mold made of steel, aluminum alloy or the like, and has a donut shape as a whole. The outer surface of the rigid core 30 is the inner surface of a vulcanized pneumatic tire. Is the same shape. An unvulcanized tire 31 is attached to the outside of the rigid core 30. The unvulcanized tire 31 is formed by, for example, knitting and winding a rubberized cord and a belt-shaped rubber around the rigid core 30. Can be molded.

  The rigid core 30 is configured by arranging a plurality of arc-shaped, here ten core segments 32 in close contact with each other in the circumferential direction. These core segments 32 are composed of two types of segments: a fan-shaped segment whose planar shape is a fan shape and a mountain-shaped segment having a substantially trapezoidal shape, and these fan-shaped and mountain-shaped segments are alternately arranged in the circumferential direction. In the present invention, both end surfaces in the circumferential direction of the chevron segments may be parallel to each other.

  Each core segment 32 has a through chamber 33 extending in the circumferential direction, and these through chambers 33 are open at both ends of the core segment 32 in the circumferential direction. Here, when the core segment 32 is assembled in the state of being closely contacted in the circumferential direction as described above, all the through chambers 33 communicate with each other in a ring shape, and the rigid core 30 is heated from the inside to the inside of the rigid core 30. A continuous ring-shaped heating chamber 34 to which a high-temperature, high-pressure vulcanizing medium is supplied is formed.

  Arc-shaped grooves 37 extending in the circumferential direction are respectively formed on both side surfaces of each core segment 32 in the axial direction, and these arc-shaped grooves 37 are continuously formed in the axial direction of the rigid core 30 when the rigid core 30 is formed. Annular grooves 38 are formed on both side surfaces. 39 is a substantially cylindrical one side fastening body having an annular protrusion 40 at one end in the axial direction, and this one side fastening body 39 is inserted into the central space of the rigid core 30 from one side, and then the annular protrusion 40 Is inserted into the annular groove 38 to be locked to the rigid core 30.

  41 is a substantially cylindrical other side fastening body having an annular protrusion 42 at the other end in the axial direction, and is formed on the outer circumference of the other side fastening body 41 on the outer circumference of the one side fastening body 39. A female screw 44 that is screwed onto the male screw 43 is formed. When the male screw 43 and the female screw 44 are screwed together, the one side and other side fastening bodies 39 and 41 fasten the rigid core 30 from both sides, hold the rigid core 30 in a prescribed shape, and enter the heating chamber 34. Prevent leakage of the supplied vulcanizing medium. Here, the one-side and other-side fastening bodies 39 and 41 described above constitute a fastening body 45 that forms a doughnut-like rigid core 30 by fastening the core segment 32 as a whole, and the rigid body formed in this way The core 30 defines an inner surface shape from the time of molding the unvulcanized tire 31 to the end of vulcanization, and can mold the inner surface (inner surface) of the unvulcanized tire 31 at the time of vulcanization.

  2, 3, and 4, reference numeral 48 denotes a plurality (three in this case) of arc grooves formed on the outer surface of each core segment 32 in the axial direction, and these arc grooves 48 are continuous in the circumferential direction. As a result, both ends of the arc groove 48 are open at both end surfaces of the core segment 32 in the circumferential direction. These arc grooves 48 communicate with each other in a ring shape when the rigid core 30 is formed, and respectively form storage grooves 49 that continuously extend in the circumferential direction on the outer surface of the rigid core 30.

  Each of the storage grooves 49 is positioned on the opening end side (the outer surface side of the rigid core 30) in the depth direction of the storage groove 49 and on the back side (the groove bottom side), and is narrow. The convex section has a wide portion 49b wider than the portion 49a. As a result, a step 51 is formed at the boundary between the narrow portion 49a and the wide portion 49b on the side wall 50 of the storage groove 49. 54 is composed of, for example, steel, aluminum alloy, etc., and is a pair of arc blocks accommodated in each arc groove 48 side by side in the width direction of the arc groove 48, and these arc blocks 54 extend in the circumferential direction, The circumferential length and the radius of curvature are substantially the same as the circumferential length and the radius of curvature of the arc groove 48 to be accommodated.

  These arc blocks 54 constitute a pair of circumferentially extending molding blocks 55 stored in the respective storage grooves 49 when the rigid core 30 is formed. The arc block 54 is accommodated in the accommodating groove 49 by being inserted into the arc groove 48 from the circumferential opening end of the arc groove 48 of the core segment 32. The surfaces of these molding blocks 55 (arc blocks 54) are located on the extended line of the outer surface of the rigid core 30 (core segment 32). As a result, the surfaces of these molding blocks 55 are part of the outer surface of the rigid core 30. Forming part.

  In the circumferential direction, the surface-side end portion (opening-side end portion in the depth direction of the storage groove 49) that is close to the outer surface of the rigid core 30 at the opposing surfaces 56 of each forming block 55 (arc block 54). Each of the extending cutouts 57 is formed, and as a result, the surface of the molding block 55 and the facing surface 56 are linearly connected to the opposing surface 56 of each molding block 55, and the depth is increased. An inclined surface 58 inclined with respect to the vertical direction is formed. Note that the cutout 57 (inclined surface 58) described above may have an arcuate cross section.

  In addition, a recess 59 having a rectangular cross section that extends in the circumferential direction and opens to the bottom surface is provided at the back end portion (the bottom surface side end portion of the storage groove 49) of the facing surface 56 of each molding block 55 (arc block 54). The width of the recess 59 is larger than the width of the notch 57. The pair of forming blocks 55 (arc blocks 54) are stored in the storage grooves 49 (arc grooves 48) arranged in the width direction of the storage grooves 49 so that the notches 57 and the recesses 59 face each other. However, at this time, a slight gap 60 is formed between the opposing surfaces 56 of the pair of forming blocks 55 (arc blocks 54).

  As a result, a recess 61 extending continuously in the circumferential direction is formed on the outer surface of the rigid core 30 by a notch 57 formed in each of the pair of molding blocks 55. A space 62 extending continuously in the circumferential direction is formed in the rigid core 30 (on the bottom side of the storage groove 49) by the recess 59 formed in each of the molding blocks 55 and the bottom surface of the storage groove 49. Further, in the rigid core 30, a narrow passage 63 that continuously extends in the circumferential direction and communicates the recess 61 and the space 62 is formed by a gap 60 formed between the opposing surfaces 56 of both molding blocks 55. However, the width W of the narrow passage 63 is smaller than the width of the recess 61 and the space 62.

  The above-mentioned recess 59 may be formed on the facing surface 56 of each molding block 55 (arc block 54) slightly away from the bottom surface, and in this case, the space 62 is formed only by these recesses 59. Is done. Here, since the above-mentioned hollow 61 is formed by a pair of notches 57 (inclined surface 58), the width thereof gradually decreases toward the depth direction (back side) of the storage groove 49. The cross section has an inverted triangular shape. Further, a narrow passage 63 is opened at the deepest portion of the recess 61.

  When the unvulcanized tire 31 is attached to the rigid core 30, the recess 61a located at the center in the width direction of the rigid core 30 among the recesses 61 is at the center in the width direction of the tread portion T and at both ends in the width direction. The indentation 61b located in the portion overlaps both shoulder portions S. Note that the plurality of depressions extending in the circumferential direction may be formed on the outer surface of the rigid core so as to overlap other parts of the unvulcanized tire, for example, the sidewall part and the bead part. Here, if the recess 61, the space 62, and the narrow passage 63 are formed by arranging the pair of molding blocks 55 as described above in the storage groove 49 in the width direction, the recess 61, the space 62, and The rigid core 30 having the narrow passage 63 can be easily manufactured, and the manufacturing cost of the rigid core 30 can be reduced.

  Then, the unvulcanized tire 31 is closed by closing the vulcanized outer mold 27 and vulcanized with the vulcanized outer mold 27 and the rigid core 30 so that the unvulcanized tire 31 sealed and accommodated in the vulcanized space 72 constitutes the unvulcanized tire 31. The volume of the unvulcanized tire 31 is set to a value slightly larger than the volume of the vulcanized space 72, even though the rubber to be compressed is incompressible. Since the tire 31 is thermally expanded, the pressure in the vulcanization space 72 is increased, and excess unvulcanized rubber tends to protrude between the core segments 32 constituting the rigid core 30.

  However, in this embodiment, as described above, the depression 61 is provided on the outer surface of the rigid core 30, and the space 62 is formed in the rigid core 30 on the back side of the depression 61, while the depression 61 and the space 62 are formed. Are communicated with each other through the narrow passage 63, so that when the pressure in the vulcanization space 72 rises (when the vulcanized outer die 27 is closed or vulcanized), the vulcanized from the volume of the unvulcanized tire 31 by the increased pressure. Excess unvulcanized rubber with the volume of the space 72 reduced flows into the recess 61, the narrow passage 63, and the space 62 in the order described above, and is discharged from the vulcanization space 72. Thus, when excessive rubber is positively discharged from the vulcanization space 72 into the depression 61, the narrow passage 63, and the space 62, an excessive pressure increase in the vulcanization space 72 is suppressed, Generation | occurrence | production of a burr | flash can be prevented effectively.

  Further, when the rigid core 30 (core segment 32) is taken out from the vulcanized tire after the vulcanization as described above is completed, the rubber in the space 62 is caught in the recess 59, so that the rubber in the narrow passage 63 is removed. Since the rigid core 30 is pulled and cut, most of the excess rubber is removed into the narrow passage 63 and the space 62 of the rigid core 30, while the inside of the vulcanized tire is substantially hollowed out of the excess rubber. Only a portion of the rubber equivalent to 61 minutes remains as protrusions (projections) extending in the circumferential direction, which effectively suppresses variations in rubber weight in vulcanized tires and improves uniformity. Can be made.

  Since the depression 61 as described above extends in the circumferential direction, the protrusion remaining on the inner surface of the vulcanized tire extends in the circumferential direction. As a result, the tire corresponding to the protrusion The protrusions can be removed simply by rotating the vulcanized tire while providing a cutting means such as a cutter at the position in the width direction, thereby making it easy to remove excess rubber. In addition, the number of depressions 61 to be formed can be reduced as compared with the cylindrical depressions, the structure is simplified, and the manufacturing cost can be reduced.

  In addition, the above-described depression is formed, for example, by forming an arc groove in only one of the fan-shaped segment and the chevron segment or by terminating the arc groove formed in the core segment in the middle of the circumferential direction. By storing the circular arc block (molded block) in the storage groove), it may be extended intermittently in the circumferential direction. Even in this case, the protrusions are intermittently present in the circumferential direction. It can be easily removed in the same manner.

  Here, each molding block 55 (arc block 54) described above has an L-shaped cross section, and as a result, the molding block 55 (arc) is formed on the separation surface 66 located on the side of each molding block 55 that is separated from each other. One step 68 is formed as a restricting portion parallel to the surface of the block 54). When the molding block 55 is stored in the storage groove 49, the step 68 is engaged with the step 51 of the storage groove 49 while being in surface contact with the storage block 49 in the depth direction of the storage groove 49. Regulate the movement of

  In this way, if the separation surface 66 of each molding block 55 is provided with a step 68 as a restricting portion, when the rigid core 30 is taken out from the vulcanized tire, the molding block 55 is pulled by the vulcanized tire and the storage groove It is possible to prevent the situation from coming out of 49, and thus the rubber can be surely cut in the narrow passage 63, while the unvulcanized tire 31 is molded outside the rigid core 30 while rotating around the axis. In this case, it is possible to prevent the molding block 55 from coming out of the storage groove 49 due to centrifugal force. As described above, if the restricting portion is configured by the step 68 that engages with the step 51 formed on the side wall 50 of the storage groove 49, the structure is simple and the manufacturing is easy. Can be reliably prevented from coming out of the storage groove 49.

  Here, the width W of the narrow passage 63 is preferably in the range of 0.5 mm to 1.5 mm. The reason is that if the width W is less than 0.5 mm, the width W of the narrow passage 63 becomes too narrow due to thermal expansion of the rigid core 30 and the molding block 55 during vulcanization, and the extra rubber narrow passage 63 and the space 62 While the inflow to the inside is restricted and the above-described burrs may occur, if the width W exceeds 1.5 mm, the rubber constituting the tire may be used even if the pressure in the vulcanization space 72 does not increase so much. The rubber flows into the narrow passage 63 and the space 62 and the amount of rubber in the tire is insufficient. When the rigid core 30 (core segment 32) is taken out from the vulcanized tire, excess rubber in the narrow passage 63 is easily cut. In other words, a large stress may be generated in the vulcanized tire.

  However, if the width W of the narrow passage 63 is within the above-described range, the rubber constituting the tire can flow into the narrow passage 63 and the space 62 and prevent the tire rubber amount from being insufficient. Even if the core 30 is thermally expanded, excess rubber can be surely flowed into the narrow passage 63 and the space 62. Furthermore, the rubber in the narrow passage 63 can be removed by simply removing the rigid core 30 from the vulcanized tire. This is because the thickness is easily cut and a situation in which a large stress is generated in the vulcanized tire can be avoided. In addition, what is necessary is just to set the value of the said width W suitably according to a tire internal diameter. Further, if the depth D and width H of the notch 57 are both in the range of 0.5 mm to 3.0 mm, excess rubber can be surely and sufficiently allowed to flow into the narrow passage 63 and the space 62. The depth D and the width H are preferably within the above-mentioned ranges.

  Furthermore, as described above, if the width of the depression 61 is gradually reduced in the depth direction and the narrow passage 63 is opened at the deepest portion of the depression 61, excess rubber is removed by the depression 61. Since it can be smoothly guided into the narrow passage 63 and the space 62, it is preferable to configure as described above. The rubber in the narrow passage 63 and the space 62 can be easily removed by taking out the arc block 54 from the circumferential opening end of the arc groove 48 of the disassembled core segment 32. Even if extra rubber is left in 30, the cleaning operation of the rigid core 30 is simplified.

Next, the operation of the first embodiment will be described.
First, the fan-shaped and mountain-shaped segments constituting the core segment 32 are alternately arranged in close contact with each other in the circumferential direction, and the core segments 32 are fastened by the fastening body 45 to form the rigid core 30 having a donut shape. At this time, in the storage groove 49 of the rigid core 30, a pair of molding blocks 55 formed with notches 57 and dents 59 are stored side by side in the width direction of the storage groove 49, so the rigid core 30 A recess 61 is provided on the outer surface of the core, and a space 62 is formed in the rigid core 30 on the back side of the recess 61.

  Further, since a gap 60 is formed between the facing surfaces 56 of the molding block 55, a narrow passage 63 that connects the recess 61 and the space 62 is formed in the rigid core 30. Next, an unvulcanized tire 31 is formed by knitting and winding a rubberized cord and a belt-like rubber around the outer side of the rigid core 30 while rotating the rigid core 30 about its axis. Next, the rigid core 30 on which the unvulcanized tire 31 is mounted on the outside is carried into the tire vulcanizing device 11 by a conveying device (not shown) and placed horizontally on the lower mold 14. Of the three depressions 61, the depression 61a overlaps the center of the tread portion T in the width direction, and the depressions 61b located on both outer sides in the width direction of the depression 61a overlap the shoulder portions S, respectively.

  Next, the upper base 15 and the upper plate 21 are integrally lowered with a predetermined gap between the upper platen 16 and the upper plate 21. When the holder 24 comes into contact with the upper surface of the lower base 12 and the upper mold 22 comes into contact with the unvulcanized tire 31, the lowering of the upper plate 21 is stopped. Next, as described above, even after the lowering of the upper plate 21 is stopped, only the upper base 15 is continuously lowered to bring the upper base 15 closer to the upper plate 21. When the upper base 15 approaches the upper plate 21 in this manner, the outer ring 23 causes the sector mold 25 to move synchronously inward in the radial direction by the wedge action of the inner and outer peripheries 23a and 24a.

  Then, when the upper base 15 is lowered to the lower limit, the sector mold 25 moves to the inner limit in the radial direction and the vulcanized outer die 27 is closed. A vulcanized space 72 in which an unvulcanized tire 31 is hermetically stored is formed between the outer mold 27 and the rigid core 30. At this time, the pressure in the vulcanized space 72 rises as described above, and excess rubber of the unvulcanized tire 31 flows into the recess 61 of the rigid core 30, so that the opposing surfaces 56 of the pair of molding blocks 55 are Even if they are in close contact with each other, the molding block 55 moves outward in the width direction so as to be separated from each other by being pushed by the excessive rubber pressing force acting on the inclined surface 58. As a result, the narrow passage 63 is opened and the extra rubber is opened. Surely flows into the space 62 through the depression 61 and the narrow passage 63.

  Next, after applying a large clamping force to the upper base 15, a high-temperature and high-pressure vulcanizing medium is supplied into the lower and upper platens 13 and 16, the holder 24 and the rigid core 30 to remove the unvulcanized tire 31. At this time, the outer surface of the unvulcanized tire 31 is molded by the vulcanized outer mold 27, while the inner surface is molded by the rigid core 30. Further, since the rigid core 30 and the unvulcanized tire 31 are thermally expanded during such vulcanization, the pressure in the vulcanized space 72 is increased, and excess rubber in the unvulcanized tire 31 is recessed 61 and the narrow passage 63. Through the space 62 in this order.

  Thus, when the outer mold is closed or vulcanized, excess unvulcanized rubber is positively discharged from the vulcanization space 72 into the recess 61, the narrow passage 63 and the space 62 due to the increased pressure. An excessive pressure increase in the sulfur space 72 is suppressed, and the generation of burrs is effectively prevented. Then, as described above, when the vulcanization of the unvulcanized tire 31 is completed to become a vulcanized tire, the vulcanized tire is mounted after the vulcanized outer mold 27 is opened by the reverse operation to the above. The rigid core 30 is transported to the work position by the transport device. Then, at this work position, the core segment 32 is disassembled and sequentially taken out from the vulcanized tire.

  At this time, the rubber in the space 62 and the rubber constituting the vulcanized tire are narrower than those at the start of vulcanization due to thermal expansion of the molding block 55 (the entire rigid core 30) by vulcanization. Since it is only connected by the rubber in the passage 63, the narrow rubber in the narrow passage 63 is pulled by the rigid core 30 and easily cut. As a result, most of the excess rubber is removed in the narrow passage 63 and the space 62 of the rigid core 30, while only about 61 minutes of the excess rubber is formed as a small protrusion on the inner surface of the vulcanized tire. As a result, variation in rubber weight in the vulcanized tire is effectively suppressed, and uniformity can be improved.

  After that, as described above, the arc block 54 is taken out from the circumferential opening end of the arc groove 48 from the arc groove 48 of each core segment 32 taken out from the vulcanized tire, and the rubber in the narrow passage 63 and the space 62 is removed. On the other hand, excess protrusions remaining on the inner surface of the vulcanized tire are removed by excision means while rotating the vulcanized tire.

    FIG. 5 is a diagram showing Embodiment 2 of the present invention. In this embodiment, an inclined surface 77 inclined outward in the width direction toward the depth direction is formed on the entire side wall 76 of the storage groove 75 extending in the circumferential direction formed on the outer surface of the rigid core 30. The cross section of the storage groove 75 is substantially trapezoidal. In addition, the entire separation surface 79 of the pair of molding blocks 78 stored in the storage groove 75 is inclined outward in the width direction toward the depth direction of the storage groove 75, and is the same gradient as the inclined surface 77. An inclined surface 80 as a part is formed.

  The inclined surface 80 engages with the inclined surface 77 when the molding block 78 is stored in the storage groove 75, and restricts movement of the storage groove 75 in the depth direction of the molding block 78. The inclined surfaces 77 and 80 described above may be formed on part of the side wall 76 and the separation surface 79. If the movement of the molding block 78 in the depth direction of the storage groove 75 is regulated by such an inclined surface 80, the molding block 78 may come out of the storage groove 75 while the structure is simple and easy to manufacture. Can be reliably prevented. Other configurations and operations are the same as those in the first embodiment.

    In the above-described embodiment, the recess 61, the narrow passage 63, and the space 62 are formed by arranging the pair of molding blocks 55 and 78 side by side in the width direction of the storage grooves 49 and 75. In the invention, for example, a recess, a narrow passage, and a space may be formed directly in the rigid core (core segment), or a recess, narrow passage, and space are formed in one molding block (arc block) instead of a pair. While being formed, the one molding block (arc block) may be stored in a storage groove (arc groove). In the above-described embodiment, the space 62 is formed by the recess 59 formed in the molding blocks 55 and 78. However, in the present invention, the space is formed on the bottom surface of the storage groove, and the narrow passage is formed. You may make it comprise from a wider groove | channel, and the dent of a shaping | molding block can be abbreviate | omitted in this case.

  Furthermore, in the present invention, at least one arc block (molding block) having a surface in which a notch and a recess are formed is formed into an arc groove (storage groove) having a side wall extending in the depth direction. May be formed in the inner mold so as to form a recess, a narrow passage, and a space. Moreover, in this invention, you may make it provide two or more level | step differences as a control part in the separation surface of each shaping | molding block.

  The present invention can be applied to the industrial field of vulcanizing an unvulcanized tire housed in a vulcanization space between an outer mold and an inner mold.

It is front sectional drawing which shows Example 1 of this invention. It is front sectional drawing of an inner type. It is a top view of the core segment which comprises an inner type. It is front sectional drawing of a hollow, a narrow channel | path, and space vicinity. It is front sectional drawing similar to FIG. 4 which shows Embodiment 2 of this invention.

Explanation of symbols

11… Tire vulcanizer 27… Outer type
30 ... Inner mold 31 ... Unvulcanized tire
49, 75 ... Storage groove 50, 76 ... Side wall
51… Step 55, 78… Molding block
56 ... Opposite surface 57 ... Notch
59 ... Dent 60 ... Gap
61 ... depression 62 ... space
63 ... Narrow passage 66, 79 ... Remote surface
68 ... Step 72 ... Vulcanization space
77 ... Inclined surface 80 ... Inclined surface D ... Depth H ... Width W ... Width

Claims (10)

    A recess is provided on the outer surface, and a space is formed on the back side of the recess, and the recess and the space are not connected to a vulcanization space between the inner mold and the outer mold, each of which has a donut shape communicated by a narrow passage. A step of storing the vulcanized tire, and a step of vulcanizing the unvulcanized tire and molding the outer surface of the unvulcanized tire with the outer mold while molding the inner surface with the inner mold. A tire vulcanizing method characterized in that excess rubber of an unvulcanized tire is depressed when the pressure rises and flows into the narrow passage and the space in the above order.     A vulcanization space between the outer mold and the inner mold, the outer mold having an outer mold that can mold the outer surface of the unvulcanized tire and a donut-shaped inner mold that can mold the inner surface of the unvulcanized tire In the tire vulcanizing apparatus adapted to vulcanize the unvulcanized tire stored in the inner mold, a recess is provided on the outer surface of the inner mold, and a space is formed in the inner mold on the back side of the recess. A tire characterized in that a hollow and a space are communicated by a narrow passage, and excess rubber of the unvulcanized tire is recessed when the pressure in the vulcanized space rises, and flows into the narrow passage and the space in the order described above. Vulcanizing equipment.     The tire vulcanizer according to claim 2, wherein the recess extends in the circumferential direction.     A storage groove extending in the circumferential direction is formed on the outer surface of the inner mold, and a pair of molding blocks extending in the circumferential direction are stored in the storage groove side by side in the width direction of the storage groove, and the molding blocks face each other. A notch is formed in the surface side end portion close to the outer surface of the inner mold on the facing surface, and a recess is formed in the back side end portion of the facing surface, while a gap is formed between the facing surfaces of the pair of molding blocks. The tire vulcanizing apparatus according to claim 2, wherein the recess is formed by the notch of the two molding blocks, the space is formed by the depression of the two molding blocks, and the narrow passage is formed by the gap.     The tire vulcanizer according to claim 4, wherein the narrow passage has a width W in a range of 0.5 mm to 1.5 mm.     The tire vulcanizer according to claim 4 or 5, wherein both the depth D and the width H of the notches are in the range of 0.5 mm to 3.0 mm.     The tire vulcanizer according to any one of claims 4 to 6, wherein a regulating portion for regulating movement of the molding block in the depth direction of the storage groove is provided on a separation surface of the pair of molding blocks.     The tire vulcanizer according to claim 7, wherein the restricting portion is a step that engages with a step formed on a side wall of the storage groove.     The tire vulcanizer according to claim 7, wherein the restricting portion is an inclined surface that is formed on a side wall of the storage groove and engages with an inclined surface that is inclined outward in the width direction in the depth direction.     The tire vulcanizer according to any one of claims 3 to 9, wherein a width of the recess is gradually reduced in a depth direction, and a narrow passage is opened at a deepest portion of the recess.

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