JP2010201885A - Tire vulcanizing device and tire manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a tire vulcanizing device capable of restraining manufacturing failure such as chipping of a block by extraction of a blade, and a tire manufacturing method using the tire vulcanizing device. <P>SOLUTION: This tire vulcanizing device 1 includes a sector mold 120 of diametrically expanding in a radial shape in the tire radial direction by a plurality of segments divided into a plurality in the tire peripheral direction by forming a tread pattern in a tread 11 of a raw tire 10, and a blade for forming sipes in the tread 11 by rising inward in the tire radial direction in an inner peripheral surface 112a of the sector mold 120 contacting with the tread 11. The sector mold 120 is formed with air vents 123A and 123B communicating toward the inner peripheral surface 112a from an external part of the sector mold 120 and sending air into from the external part of the sector mold 120. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a tire vulcanizing apparatus and a tire manufacturing method including a sector mold that forms a tread pattern on a tread of a raw tire, and a blade that rises inward in the tire radial direction on the inner side surface of the sector mold.

  2. Description of the Related Art Conventionally, a tire vulcanizing apparatus including a split mold that forms a tread pattern or a sidewall pattern while vulcanizing an unvulcanized pneumatic tire (so-called green tire) is known. Such a split mold includes a side mold that forms a pattern or the like on a sidewall and a sector mold that forms a tread pattern.

  The side mold includes a lower mold on which the green tire is placed and an upper mold that moves in the tread width direction. On the other hand, the sector mold is configured by segments that are divided into a plurality (for example, nine) along the tire circumferential direction. Each segment moves along the tire radial direction. Thereby, the sector mold can be radially expanded along the tire radial direction.

  The sector mold is provided with a blade that forms a sipe that improves running performance (for example, steering stability and drainage performance) on an icy and snowy road surface. The blade rises inward in the tire radial direction so as to be substantially orthogonal to the tread surface on the inner surface of the sector mold in contact with the tread.

  When removing a pneumatic tire vulcanized by such a tire vulcanizer from the tire vulcanizer (hereinafter referred to as tire removal), first, the upper mold is moved in the tread width direction so as to be separated from the lower mold. To do. Next, the sector mold radially expands by moving each segment in the tire radial direction. Thereby, the pneumatic tire mounted on the lower mold can be taken out.

JP 2007-33270 A (page 2-3, FIG. 1)

  By the way, in recent pneumatic tires, the shape of the sipe tends to become complicated as the demand for running performance on an icy and snowy road surface increases.

  However, the conventional tire vulcanizing apparatus described above has the following problems. That is, if the shape of the blade is complicated to form a complicated sipe, the blade may be caught by the tread rubber when the tire is taken out.

  Specifically, in the central region of the sector mold corresponding to the tire equator line of the pneumatic tire, the direction in which the blade is pulled out from the tread (blade pulling direction), and the direction in which the sector mold expands (mold expanding direction) Are almost matched. However, in the end region of the sector mold corresponding to the tread end portion of the pneumatic tire, an angle difference occurs between the blade drawing direction and the mold diameter increasing direction, and the blade is easily caught by the tread rubber. For this reason, in particular, there has been a problem in that manufacturing defects such as chipping of blocks occur at the tread end portion of the pneumatic tire.

  Accordingly, an object of the present invention is to provide a tire vulcanizing apparatus capable of suppressing manufacturing defects such as chipping of a block due to drawing of a blade, and a tire manufacturing method using the tire vulcanizing apparatus.

  In order to solve the above-described problems, the present invention has the following features. First, the first feature of the present invention is that a tread pattern is formed on a tread (tread 11) of a raw tire (raw tire 10), and a plurality of segments divided into a plurality along the tire circumferential direction are used in the tire radial direction. A sector mold (sector mold 120) that radially expands along and an inner side surface (inner peripheral surface 112a) of the sector mold that comes into contact with the tread rises inward in the tire radial direction and forms a groove in the tread. A tire vulcanizing apparatus (tire vulcanizing apparatus 1) including a blade (blade 130), which communicates with the sector mold from the outside of the sector mold toward the inner surface, and from the outside of the sector mold. The gist is that a ventilation part (vent hole 123) through which air is fed is formed.

  According to such a feature, the sector mold is formed with a ventilation portion that communicates from the outside of the sector mold toward the inner surface and into which air is sent from the outside of the sector mold. According to this, when the tire is taken out, air enters between the blade and the tread rubber, and a gap is generated between the blade and the tread rubber. Therefore, when the tire is taken out, the blade is less likely to be caught by the rubber of the tread, and it is possible to suppress manufacturing defects such as chipping of the block or block collapse due to drawing of the blade.

  The second feature of the present invention relates to the first feature of the present invention, and further comprises an air injection part (air injection part 150) provided outside the sector mold and for feeding the air into the ventilation part. The gist.

  A third feature of the present invention relates to the first or second feature of the present invention, and is characterized in that the ventilation portion has a function of discharging air between the inner surface and the tread.

  A fourth feature of the present invention is a tire vulcanization comprising: a sector mold that forms a tread pattern on a tread of a raw tire; and a blade that rises inward in the tire radial direction on an inner surface of the sector mold in contact with the tread. A tire manufacturing method for manufacturing a pneumatic tire using an apparatus, wherein the sector tire is radially expanded along a tire radial direction, whereby the pneumatic tire manufactured by the tire vulcanizing apparatus is A step of removing the tire mold from a tire vulcanizing device, wherein in the step, when the sector mold is separated from the tread, the sector mold and the sector mold are communicated from the outside of the sector mold toward the inner surface. The gist is that air is fed into the gap with the tread.

  A fifth feature of the present invention relates to the fourth feature of the present invention, in which air is fed into the gap through the ventilation portion for at least 10 to 30 seconds after the sector mold is separated from the tread. It is a summary.

  A sixth feature of the present invention relates to the fourth or fifth feature of the present invention, and is summarized in that the pressure of the air fed into the gap is 0.2 to 0.5 MPa.

  According to the features of the present invention, it is possible to provide a tire vulcanizing apparatus capable of suppressing manufacturing defects such as chipping of a block due to blade drawing and a tire manufacturing method using the tire vulcanizing apparatus.

FIG. 1 is a cross-sectional view showing a part of a tire vulcanizing apparatus 1 according to this embodiment. FIG. 2 is a perspective view showing the sector mold 120 according to the present embodiment (No. 1). FIG. 3 is a perspective view showing the sector mold 120 according to the present embodiment (No. 1). FIG. 4 is a perspective view showing one segment of the sector mold 120 according to the present embodiment. FIG. 5 is a flowchart showing the tire manufacturing method according to the present embodiment. FIG. 6 is a diagram showing an air flow in the tire housing process according to the present embodiment. FIG. 7 is a view showing an air flow in the tire take-out process according to the present embodiment.

  Next, embodiments of a tire vulcanizing apparatus and a tire manufacturing method according to the present invention will be described with reference to the drawings. Specifically, (1) Configuration of tire vulcanizer, (2) Tire manufacturing method, (3) Comparative evaluation, (4) Action / effect, (5) Other embodiments will be described.

  In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals. However, it should be noted that the drawings are schematic and ratios of dimensions are different from actual ones.

  Accordingly, specific dimensions and the like should be determined in consideration of the following description. Moreover, it is a matter of course that portions having different dimensional relationships and ratios are included between the drawings.

(1) Configuration of Tire Vulcanizing Device First, the configuration according to this embodiment will be described with reference to the drawings. FIG. 1 is a cross-sectional view showing a part of a tire vulcanizing apparatus 1 according to this embodiment. 2 and 3 are perspective views showing the sector mold 120 according to the present embodiment. FIG. 4 is a perspective view showing one segment of the sector mold 120 according to the present embodiment.

  As shown in FIG. 1, the tire vulcanizing apparatus 1 includes a split mold 100 that forms a tread pattern, a sidewall pattern, and the like while vulcanizing an unvulcanized pneumatic tire (so-called green tire 10). . The split mold 100 includes a side mold 110, a sector mold 120, and a blade 130.

(1-1) Side Mold The side mold 110 forms a pattern or the like on the sidewall. As shown in FIG. 1, the side mold 110 includes a lower mold 111 and an upper mold 112.

  The lower mold 111 is fixed to the lower container 140A. The raw tire 10 is placed on the lower mold 111. In the lower mold 111, an inner peripheral surface 111a that forms a pattern or the like on one sidewall of the raw tire 10, and an exhaust hole 111b from which air between the inner peripheral surface 111a and the sidewall of the raw tire 10 is discharged. Is formed. In addition, between the lower mold 111 and the lower container 140A, a passage groove 111c through which air between the inner peripheral surface 112a flowing through the discharge hole 111b and the sidewall passes is provided.

  The upper mold 112 is processed into the upper container 140B. The upper mold 112 moves in the tread width direction. The upper mold 112 has an inner peripheral surface 112 a that forms a pattern or the like on one sidewall of the raw tire 10, and a discharge hole 112 b that discharges air between the inner peripheral surface 112 a and the sidewall of the raw tire 10. It is formed. In addition, between the upper mold 112 and the upper container 140B, a passage groove 112c through which air between the inner peripheral surface 112a flowing through the discharge hole 112b and the sidewall passes is provided.

(1-2) Sector Mold The sector mold 120 forms a tread pattern. The sector mold 120 includes an outer ring 121 and a plurality of segments 122. The outer ring 121 has an annular shape and moves along the tread width direction (vertical direction in the present embodiment). As shown in FIG.2 and FIG.3, the some segment 122 is divided | segmented into plurality (for example, 9 pieces), and moves along a tire radial direction. That is, the segment 122 radially expands along the tire radial direction.

  The sector mold 120 is formed with a vent hole 123 (a vent portion) that communicates from the outside of the sector mold 120 toward the inner peripheral surface 112a and into which air is sent from the outside of the sector mold 120. The vent hole 123 includes a vent hole 123 </ b> A formed in each segment 122 and a vent hole 123 </ b> B formed between another member such as the outer ring 121 and the segment 122.

  Such a vent 123 has a function of discharging air between the inner peripheral surface 112a of the sector mold 120 and the tread 11 (so-called vent hole function). Outside the sector mold 120, an air injection unit 150 that sends air into the air holes 123 is provided.

(1-3) Blade As shown in FIG. 4, the blade 130 forms a sipe (groove) in the tread 11. The blade 130 rises toward the inner side in the tire radial direction on the inner side surface 120A of the sector mold 120 in contact with the tread 11 so as to be substantially orthogonal to the tread surface of the tread 11. The blade 130 has a zigzag shape toward the inner side in the tire radial direction.

(2) Tire Manufacturing Method Next, a tire manufacturing method according to the present embodiment will be described with reference to the drawings. FIG. 5 is a flowchart showing the tire manufacturing method according to the present embodiment. FIG. 6 is a diagram showing an air flow in the tire housing process according to the present embodiment. FIG. 7 is a view showing an air flow in the tire take-out process according to the present embodiment.

  As shown in FIG. 5, the tire manufacturing method includes a tire housing step, a tire vulcanizing step, and a tire removing step.

(2-1) Tire housing process In the tire housing process S1, the raw tire 10 is housed in the tire vulcanizing apparatus 1 described above. Specifically, the raw tire 10 is placed on the lower mold 111, and the sector mold 120 and the upper mold 112 move so as to approach the raw tire 10.

(2-2) Tire vulcanization step In the tire vulcanization step S2, a pneumatic tire is molded by subjecting the raw tire 10 to vulcanization treatment under predetermined conditions in the tire vulcanization apparatus 1. At this time, as shown in FIG. 6, the air between the tread 11 of the raw tire 10 that is inflated from the inner peripheral surface by the bladder 160 and the inner peripheral surface 112 a of the sector mold 120 is discharged through the vent hole 123. The

(2-3) Tire Extraction Step In the tire extraction step, the sector tire 120 is radially expanded along the tire radial direction so that the pneumatic tire vulcanized by the tire vulcanizer 1 is converted into the tire vulcanizer 1. Take out from. Specifically, as shown in FIG. 7, when the sector mold 120 is separated from the tread 11, the air injection unit 150 passes through a vent hole 123 communicating from the outside of the sector mold 120 toward the inner peripheral surface 112 a. Air is sent into the gap between the sector mold 120 and the tread 11. The time when the sector mold 120 is separated from the tread 11 indicates the moment (including some errors) when the sector mold 120 is separated from the tread 11.

  At this time, air is fed into the gap between the sector mold 120 and the tread 11 through the air holes 123 by the air injection unit 150 for at least 10 to 30 seconds after the sector mold 120 is separated from the tread 11. The pressure of the air sent into the gap between the sector mold 120 and the tread 11 is 0.2 to 0.5 MPa.

(3) Comparative Evaluation Next, in order to further clarify the effects of the present invention, comparative evaluation performed using tire vulcanizers according to the following comparative examples and examples will be described. Specifically, (3-1) Configuration of each tire vulcanizer and (3-2) evaluation results will be described. In addition, this invention is not limited at all by these examples.

(3-1) Configuration of Each Tire Vulcanizing Apparatus First, the tire vulcanizing apparatus according to the comparative example and Examples 1 to 15 will be briefly described. The data relating to the tire vulcanizer was measured under the following conditions.

・ Tire size to vulcanize: 11R22.5 (tires for large vehicles)
・ Mold release agent: Aqueous silicon (10% concentration)
In the tire vulcanizing apparatus according to the comparative example, when the pneumatic tire vulcanized by the tire vulcanizing apparatus is taken out from the tire vulcanizing apparatus (hereinafter, when the tire is taken out), air is formed in the gap between the sector mold 120 and the tread 11. Is not sent.

  On the other hand, in the tire vulcanizing apparatus 1 according to the embodiment, air is sent into the gap between the sector mold 120 and the tread 11 by the air injection unit 150 when the tire is taken out. At this time, in the tire vulcanizing apparatus 1 according to the embodiment, air is sent into the gap between the sector mold 120 and the tread 11 for 15 seconds after the sector mold 120 is separated from the tread 11. Moreover, the pressure of the air sent into the gap between the sector mold 120 and the tread 11 is 0.3 MPa.

(3-2) Evaluation Results Next, evaluation results of pneumatic tires molded by the tire vulcanizing apparatus according to the comparative examples and examples described above will be described with reference to Table 1.

  100 pneumatic tires were molded by each tire vulcanizer. As a result, as shown in Table 1, the pneumatic tire molded by the tire vulcanizing apparatus 1 according to the example is formed on the tread 11 as compared with the pneumatic tire molded by the tire vulcanizing apparatus according to the comparative example. It has been found that the incidence of manufacturing defects due to chipped blocks is reduced. In addition, it was also found that the pneumatic tire molded by the tire vulcanizing apparatus 1 according to the example does not cause a manufacturing defect due to the block falling when the tire is taken out.

(4) Action / Effect In the embodiment, the sector mold 120 is formed with a vent hole 123 that communicates from the outside of the sector mold 120 toward the inner peripheral surface 112a and into which air is sent from the outside of the sector mold 120. According to this, air enters between the blade 130 and the rubber of the tread 11 when the tire is taken out, and a gap is generated between the blade 130 and the rubber of the tread 11. Therefore, when the tire is taken out, the blade 130 is not easily caught by the rubber of the tread 11, and it is possible to suppress manufacturing defects such as a chipped block or a block collapse due to the blade 130 being pulled out.

  In particular, even when the shape of the blade 130 is complicated (for example, a zigzag shape) in order to form a complicated sipe, air enters between the blade 130 and the rubber of the tread 11 when the tire is taken out. Is effective because it is less likely to be caught by the rubber of the tread 11.

  In the embodiment, the vent hole 123 has a function of discharging air between the inner peripheral surface 112a of the sector mold 120 and the tread 11 (so-called vent hole function). According to this, when the raw tire 10 is accommodated in the tire vulcanizer 1 (when the tire is accommodated), the air between the inner peripheral surface 112a of the sector mold 120 and the tread 11 is discharged through the vent hole 123. Is done. Therefore, it is possible to suppress manufacturing defects such as block dents caused by the raw tire 10 being vulcanized in a state where air is accumulated between the inner peripheral surface 112a and the tread 11.

  In the embodiment, when the sector mold 120 is separated from the tread 11, the sector mold 120, the tread 11, and the tread 11 are connected via the air holes 123 communicated from the outside of the sector mold 120 to the inner peripheral surface 112 a by the air injection unit 150. Air is sent into the gap. According to this, even when the shape of the blade 130 becomes complicated in order to form a complicated sipe, air enters between the blade 130 and the rubber of the tread 11 when the tire is taken out, and the blade 130 and the tread. A gap is formed between the rubber 11 and the rubber 11. Therefore, when the tire is taken out, the blade 130 is not easily caught by the rubber of the tread 11, and it is possible to suppress manufacturing defects such as a chipped block or a block collapse due to the blade 130 being pulled out.

  In the embodiment, air is sent into the gap between the sector mold 120 and the tread 11 through the vent hole 123 for at least 10 to 30 seconds after the sector mold 120 is separated from the tread 11. If the time during which air is fed into the gap is shorter than 10 seconds, it may be difficult for air to enter between the blade 130 and the rubber of the tread 11 when the shape of the blade 130 is complicated. On the other hand, if the time during which the air is sent into the gap is longer than 30 seconds, the blade 130 is completely pulled out, so that air is wasted.

  In the embodiment, the pressure of the air fed into the gap between the sector mold 120 and the tread 11 is 0.2 to 0.5 MPa. If the air pressure is less than 0.2 MPa, the air may be difficult to enter between the blade 130 and the rubber of the tread 11 when the shape of the blade 130 is complicated. On the other hand, if the air pressure is greater than 0.5 MPa, the sipe formed by the blade 130 may swell excessively between the blade 130 and the rubber of the tread 11, and the bottom of the sipe may be peeled off. .

(5) Other Embodiments As described above, the contents of the present invention have been disclosed through the embodiments of the present invention. However, it is understood that the description and drawings constituting a part of this disclosure limit the present invention. Should not. From this disclosure, various alternative embodiments, examples and operational techniques will be apparent to those skilled in the art.

  For example, the embodiment of the present invention can be modified as follows. Specifically, in the embodiment, the tire vulcanizing device 1 has been described as molding a pneumatic tire by vulcanizing the raw tire 10, but the present invention is not limited to this, and other than pneumatic A tire (for example, a solid tire) or the like may be formed.

  In addition, the tire vulcanizing apparatus 1 has been described as a so-called segment type in which the sector mold 120 is divided into a plurality of pieces, but is not limited thereto, and is divided into two along the tread width direction. A two-piece type may be used. In this case, the tire vulcanizing apparatus 1 is of course different from the configuration described in the above-described embodiment.

  The vent hole 123 has been described as having a function of discharging air between the inner peripheral surface 112a and the tread 11 in addition to a function of sending air between the inner peripheral surface 112a and the tread 11. However, the present invention is not limited to this, and each may be provided separately.

  Further, the time during which air is sent into the gap between the sector mold 120 and the tread 11 and the pressure of the air that sends air into the gap are not limited to those described in the embodiment, and are appropriately selected according to the purpose. Of course you can.

  In addition, there is no restriction | limiting in particular about the tire vulcanizing apparatus 1 (side mold 110, sector mold 120, blade 130), the raw tire 10 (pneumatic tire) structure, shape, number etc. which were demonstrated by embodiment, According to the objective Of course, it can select suitably. For example, the blade 130 does not necessarily have a zigzag shape, and may have a straight shape.

  As described above, the present invention naturally includes various embodiments that are not described herein. Therefore, the technical scope of the present invention is defined only by the invention specifying matters according to the scope of claims reasonable from the above description.

DESCRIPTION OF SYMBOLS 1 ... Tire vulcanizer, 10 ... Raw tire, 11 ... Tread, 100 ... Split mold, 110 ... Side mold, 111 ... Lower mold, 111a ... Inner peripheral surface, 111b ... Discharge hole, 111c ... Passing groove, 112 ... Upper mold, 112a ... inner peripheral surface, 112b ... discharge hole, 112c ... passing groove, 120 ... sector mold, 120A ... inner side surface, 121 ... outer ring, 122 ... segment, 123 (123A, 123B) ... ventilation hole (ventilation part) ), 130 ... blade, 140A ... lower container, 140B ... upper container, 150 ... air injection part 150, 160 ... bladder

Claims (6)

A sector mold that forms a tread pattern on the tread of the raw tire and radially expands along the tire radial direction by a plurality of segments divided along the tire circumferential direction;
A tire vulcanizing device comprising a blade that rises toward the inner side in the tire radial direction on the inner side surface of the sector mold in contact with the tread and forms a groove in the tread,
A tire vulcanizer in which the sector mold is formed with a ventilation portion that communicates from the outside of the sector mold toward the inner side surface and into which air is sent from the outside of the sector mold.   The tire vulcanizing apparatus according to claim 1, further comprising an air injecting unit that is provided outside the sector mold and feeds the air into the ventilation unit.   The tire vulcanizing apparatus according to claim 1, wherein the ventilation portion has a function of discharging air between the inner side surface and the tread. Using a tire vulcanizing device comprising a sector mold that forms a tread pattern on a tread of a raw tire, and a blade that rises toward the inside in the tire radial direction on the inner surface of the sector mold that contacts the tread, A tire manufacturing method for manufacturing,
A step of removing the pneumatic tire produced by the tire vulcanizer from the tire vulcanizer by radially expanding the sector mold along the tire radial direction;
In the process,
A tire manufacturing method in which air is sent into a gap between the sector mold and the tread through a ventilation portion communicating from the outside of the sector mold toward the inner surface when the sector mold is separated from the tread.   The tire manufacturing method according to claim 4, wherein air is sent into the gap through the ventilation portion for at least 10 to 30 seconds after the sector mold is separated from the tread.   The tire manufacturing method according to claim 4 or 5, wherein the pressure of the air fed into the gap is 0.2 to 0.5 MPa.

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