JP6371548B2 - Rigid core device for manufacturing pneumatic tire and method for manufacturing pneumatic tire - Google Patents

Description

  The present invention relates to a rigid core device for manufacturing a pneumatic tire and a method for manufacturing a pneumatic tire.

  In recent years, a rigid core device has been proposed as a device for manufacturing a pneumatic tire having excellent uniformity (see, for example, Patent Document 1 below). The rigid core device includes an annular core body in which a plurality of segments are arranged in the tire circumferential direction. Various unvulcanized rubber members are attached to the outside of the core body to form a green tire. The raw tire is placed in a mold together with the core body and vulcanized, for example. When the vulcanization is finished, the core body is disassembled in the tire, and the segments are taken out one by one.

JP 2013-6367 A

  The rigid core device includes a temperature adjusting device for heating the core body in order to heat the green tire from the inside. In the conventional temperature control device, a heating medium such as a high-temperature fluid is supplied to a chamber provided in each segment to heat each segment.

  By the way, each segment constituting the core body has different temperature rise characteristics based on the difference in volume and chamber volume during heating. For example, a segment with a large volume shows a gradual temperature rise tendency as a relative segment. On the other hand, a segment with a small volume shows a rapid temperature rising tendency as a relative segment.

  However, since the conventional temperature control device supplies the heating medium of the same temperature to each segment, the temperature of each segment does not become uniform, and as a result, it is difficult to uniformly vulcanize the raw tire. There was a problem.

  The present invention has been devised in view of the above circumstances, and provides a rigid core device for manufacturing a pneumatic tire and a method for manufacturing a pneumatic tire capable of uniformly vulcanizing a raw tire. This is the main purpose.

  The present invention relates to a rigid core device for manufacturing a pneumatic tire, including a core body that is formed into an annular shape by arranging a plurality of segments in the tire circumferential direction, and temperature adjusting means for heating the core body. The segment includes a first segment and a second segment having a temperature rise characteristic different from that of the first segment, and a chamber through which a heat medium enters and exits is provided in each segment. And the temperature adjusting means controls the temperature independently of the first heat medium to the chamber of the first segment and the first temperature adjusting means for supplying the first heat medium to the chamber of the first segment. And a second temperature adjusting means for supplying a second heat medium capable of performing the above.

  In the rigid core device according to the present invention, the second temperature adjusting means may be configured so that the temperature difference between the first segment and the second segment is within a predetermined range. It is desirable to adjust the temperature.

  In the rigid core device according to the present invention, the segment includes a plurality of first segments and a plurality of second segments, and the first temperature adjusting means has the same temperature as each of the first segments. The first heat medium is supplied, and the second temperature adjusting means supplies the second heat medium having the same temperature to each of the second segments.

  In the rigid core device according to the present invention, the shape of the first segment is different from the shape of the second segment, and the chamber of the first segment is substantially the same shape as the chamber of the second segment. It is desirable that

  The present invention is a method for manufacturing a pneumatic tire using a core body that is formed by arranging a first segment and a second segment having different temperature rise characteristics in the tire circumferential direction to form an annular shape. Including a step of forming a green tire on the outside of the main body and a vulcanizing step of vulcanizing the green tire together with the core main body, wherein the vulcanizing step supplies a first heat medium to the first segment. The method includes a first step of heating the first segment, and a second step of supplying a second heat medium whose temperature is controlled independently of the first heat medium to the second segment.

  In the method for manufacturing a pneumatic tire according to the present invention, in the second step, in the second heating medium, a temperature difference between the first segment and the second segment is within a predetermined range. It is desirable to adjust the temperature.

  The rigid core device for manufacturing a pneumatic tire according to claim 1, wherein the core body is formed into an annular shape by arranging a plurality of segments in the tire circumferential direction, and temperature adjusting means for heating the core body. Is included. The segment includes a first segment and a second segment having a temperature rise characteristic different from that of the first segment. A chamber through which the heat medium enters and exits is provided inside each segment.

  The temperature adjusting means includes a first temperature adjusting means for supplying the first heating medium to the chamber of the first segment, and a second heating medium capable of controlling the temperature independently of the first heating medium to the chamber of the second segment. Second temperature adjusting means to be supplied.

  Therefore, the rigid core device according to claim 1 can supply the first heat medium and the second heat medium to each of the first segment and the second segment according to the temperature rise characteristics of the first segment and the second segment. This is useful for making the temperature of the first segment and the second segment uniform and producing a pneumatic tire free from vulcanization unevenness.

  The manufacturing method of the pneumatic tire according to claim 5 uses a core body that is formed in an annular shape by arranging the first segment and the second segment having different temperature rise characteristics in the tire circumferential direction. The method for manufacturing a pneumatic tire according to claim 5 includes a step of forming a green tire on the outer side of the core body and a vulcanizing step of vulcanizing the green tire together with the core body.

  In the vulcanization step, a first heating medium is supplied to the first segment to heat the first segment, and a second heating medium whose temperature is controlled independently of the first heating medium is supplied to the second segment. And supplying a second step.

  In the method for manufacturing a pneumatic tire according to claim 5, the first heat medium or the second heat medium is supplied to each of the first segment and the second segment according to the temperature rise characteristics of the first segment and the second segment in the vulcanization step. be able to. This is useful for making the temperature of the first segment and the second segment uniform and producing a pneumatic tire free from vulcanization unevenness.

It is sectional drawing which shows an example of the rigid core apparatus of this embodiment. It is a disassembled perspective view of a core main body. It is the bottom view which looked at the core main body from the axial direction. It is the elements on larger scale of FIG. It is explanatory drawing of a 1st heat-medium supply means. It is explanatory drawing of a 1st heat-medium discharge means. It is sectional drawing which shows the core main body and vulcanization metal mold | die during vulcanization. (A) is a graph showing the relationship between the temperature of the heat medium and the second segment of the example and the vulcanization time, and (b) is the temperature of the heat medium and the second segment of the comparative example, and the vulcanization time. It is a graph which shows the relationship.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a cross-sectional view of the rigid core device of the present embodiment. The rigid core device 1 of the present embodiment vulcanizes the raw tire Tn together with the vulcanization mold 42 that forms the outer surface of a pneumatic tire (hereinafter, simply referred to as “tire”) T, and uniformly This is an apparatus for manufacturing a tire T having excellent properties.

  The rigid core device 1 includes a core body 2 and temperature adjusting means 3 for heating the core body 2.

  The core body 2 includes an outer surface S that forms a lumen surface of the tire T. The outer surface S includes a tread molding surface portion Sa that forms the inner surface of the tread portion, and a side molding surface portion Sb that forms the inner surface of the sidewall portion and the inner surface of the bead portion, of the lumen surface of the tire T. . The outer surface S substantially matches the inner shape of the finished tire (vulcanized tire) T. On the outer surface S, for example, an unvulcanized rubber member such as a tread rubber or a side wall rubber is attached to form the raw tire Tn.

  FIG. 2 is an exploded perspective view of the core body 2. FIG. 3 is a bottom view of the core body 2 as seen from the axial direction. The core body 2 includes a plurality of segments 6 divided in the tire circumferential direction. Therefore, the core body 2 can be disassembled. The core body 2 is formed in an annular shape having a center hole 7 by assembling a plurality of segments 6 side by side in the tire circumferential direction.

  The core body 2 is formed with a bulging portion 8 that bulges from the inner side in the tire radial direction of the outer surface S to the outer side in the tire axial direction. The bulging portion 8 has a tapered surface 8s that is continuous with the outer surface S and is inclined outward in the tire axial direction toward the inner side in the tire radial direction.

  The plurality of segments 6 includes first segments 6A and second segments 6B, and are alternately arranged in the tire circumferential direction.

  The shape of the first segment 6A of the present embodiment is different from the shape of the second segment 6B. As shown in FIG. 2 and FIG. 3, the first segment 6A inclines the split surfaces 6a, 6a at both ends in the tire circumferential direction toward the inner side in the tire radial direction so that the length in the tire circumferential direction increases. I am letting. On the other hand, in the second segment 6B, the split surfaces 6b and 6b at both ends in the tire circumferential direction are inclined toward the inner side in the tire radial direction so that the length in the tire circumferential direction decreases. Thereby, the core main body 2 is taken out from the inner cavity of the vulcanized tire T (shown in FIG. 1) by sequentially moving radially inward from the first segment 6A. In the present embodiment, the volume of the first segment 6A is set smaller than the volume of the second segment 6B.

  As shown in FIG. 2, the first segment 6A includes an outer segment portion 11a disposed on the outer side in the tire radial direction and an inner segment portion 12a disposed on the inner side in the radial direction of the outer segment portion 11a. ing. The outer segment portion 11a and the inner segment portion 12a are integrally connected by a bolt 13 (shown in FIG. 1) inserted from the radially inner side of the inner segment portion 12a. Further, a sealing (not shown) is provided between the outer segment portion 11a and the inner segment portion 12a.

  Similarly to the first segment 6A, the second segment 6B includes an outer segment portion 11b and an inner segment portion 12b. The outer segment portion 11b and the inner segment portion 12b are integrally connected by a bolt 13 (shown in FIG. 1).

  As shown in FIG. 2, first dovetail joints 14 formed as ant grooves or ant tenons extending continuously in the axial direction are provided on the inner peripheral surfaces of the segments 6A and 6B. Yes. The 1st ant joint part 14 of this embodiment is formed as the ant tenon 14a. Such a first dovetail part 14 engages with a second dovetail part 32 formed on the outer peripheral surface of the core 31 described later.

  FIG. 4 is a partially enlarged view of FIG. As shown in FIGS. 3 and 4, chambers 15 and 16 through which the heat medium enters and exits are provided inside the segments 6 </ b> A and 6 </ b> B of the present embodiment, respectively. The chamber 15 of the first segment 6A has a pair of first side wall portions 15s, 15s extending along the dividing surfaces 6a, 6a, and an outer wall that connects the tire radial direction outer ends of the pair of first side wall portions 15s, 15s in the tire circumferential direction. Part 15u, a pair of first side wall parts 15s, an inner wall part 15i that joins the tire radial inner ends of 15s in the tire circumferential direction, and a pair of second parts that join the outer wall part 15u and the inner wall part 15i in the tire radial direction. Side wall portions 15t and 15t (shown in FIG. 4) are included. Therefore, the chamber 15 of the first segment 6A is formed in a substantially rectangular parallelepiped shape. Moreover, each chamber 15 is provided in the approximate center of the tire circumferential direction of each 1st segment 6A.

Similarly to the chamber 15 of the first segment 6A, the chamber 16 of the second segment 6B includes a pair of first side wall portions 16s, 16s, an outer wall portion 16u, an inner wall portion 16i, and a pair of second side wall portions 16t, 16t ( (Not shown). Moreover, each chamber 16 is provided in the approximate center of the tire circumferential direction of each 2nd segment 6B. Therefore, the chamber 15 of the first segment 6A and the chamber 16 of the second segment 6B are formed in substantially the same shape. Thereby, the manufacturing process of the chamber 15 of the first segment 6A and the chamber 16 of the second segment 6B can be made substantially the same, and the manufacturing cost can be suppressed. The “substantially the same shape” allows a difference between the volume of the chamber 15 of the first segment 6A and the volume of the chamber 16 of the second segment 6B to be 6250 mm ³ or less. Note that the shapes of the chamber 15 of the first segment 6A and the chamber 16 of the second segment 6B are preferably formed in a simple rectangular parallelepiped shape. Thereby, in this embodiment, since an advanced process is not required, manufacturing cost can further be reduced.

  As described above, the volume of the first segment 6A is set to be smaller than the volume of the second segment 6B. On the other hand, the chamber 15 of the first segment 6A and the chamber 16 of the second segment 6B have substantially the same shape. For this reason, the volume of the first segment 6A excluding the chamber 15 is smaller than the volume of the second segment 6B excluding the chamber 16. Therefore, at the time of vulcanization in which the segments 6A and 6B are vulcanized, the first segment 6A shows a rapid temperature rising tendency as a relative one. On the other hand, the 2nd segment 6B shows a moderate temperature rise tendency as a relative thing. The “temperature” is a temperature measured at a position where a temperature sensor described later is disposed.

  Each chamber 15, 16 is provided with a partition plate 18. Thereby, each chamber 15 and 16 is divided into the 1st chamber parts 15a and 16a and the 2nd chamber parts 15b and 16b, respectively. Further, on the side surface 6Ls on the one axial direction side of each first segment 6A, a first connection port 21 communicating with the first chamber portion 15a via the supply flow path 23 and a second chamber via the discharge flow path 24 are provided. A second connection port 22 communicating with the portion 15b is provided. Similarly, on the side surface 6Ls on the one axial direction side of each second segment 6B, the second connection port 25 communicates with the first chamber portion 16a via the supply flow channel 27 and the second flow channel via the discharge flow channel 28. A second connection port 26 communicating with the chamber portion 16b is provided.

  As shown in FIGS. 1 and 2, a core 31 formed in a cylindrical shape is disposed in the center hole 7 of the core body 2. As shown in FIG. 2, a second dovetail portion 32 that engages with the first dovetail portion 14 of the core body 2 is provided on the outer peripheral surface of the core 31. The second ant joint portion 32 is formed as an ant groove or ant tenon extending in the axial direction. The 2nd dovetail part 32 of this embodiment is formed as the dovetail groove | channel 32a engaged with the ant tenon 14a of the 1st dovetail part 14. FIG. The ant tenon 14a and the ant groove 32a are connected to each other so as to be relatively movable only in the axial direction by being fitted to each other.

  One side wall 33a is fixed to one end of the core 31 in the axial direction. One side wall 33a is provided with a disk-shaped side plate portion 34a. The side plate portion 34 a includes a flange portion 35 a that comes into contact with the tapered surface 8 s of the core body 2. Such a flange portion 35 a can abut the tapered surface 8 s of the core body 2 to align the one side wall 33 a and the core body 2 concentrically. Such one side wall 33a can prevent the movement of each segment 6A, 6B to one side in the axial direction.

  The other side wall 33b is fixed to the other end of the core 31 in the axial direction. The other side wall 33b is also provided with a disk-shaped side plate portion 34b. The side plate portion 34b includes a flange portion 35b that comes into contact with the tapered surface 8s of the core body 2. Such a flange portion 35b can also contact the tapered surface 8s of the core body 2 to align the other side wall 33b and the core body 2 concentrically. The other side wall body 33b of the present embodiment is detachably screwed to an inner screw portion 37 provided on the core 31. Such other side wall 33b can prevent the movement of the segments 6A, 6B to the other side in the axial direction.

  As described above, the core 31 has the second dovetail portion 32 engaged with the first dovetail portion 14 of the core body 2, and one side wall at both ends of the core 31 in the axial direction. By disposing the body 33a and the other side wall body 33b, the segments 6A and 6B can be substantially restrained to hold the core body 2 in an annular shape.

  Further, a support shaft portion 41 protruding outward in the axial direction is provided on each of the side plate portion 34a of the one side wall body 33a and the side plate portion 34b of the other side wall body 33b. The support shaft portion 41 is, for example, a gripping portion that is gripped by a transport device that transports the core body 2, or a mounting portion for mounting the transported core body 2 on a device such as the vulcanization mold 42. Is functioning as The support shaft portion 41 of the present embodiment is detachably connected to a transport device or the like via a connecting means 41a having a ball lock mechanism, for example.

  As shown in FIG. 1, the temperature adjusting means 3 supplies the heat medium 45 to the chamber 15 of each first segment 6A and the chamber 16 of each second segment 6B to heat the core body 2. It is. The temperature adjusting means 3 of the present embodiment includes a first temperature adjusting means 51 that supplies the first heat medium 45a to the chamber 15 of the first segment 6A, and a second heat medium 45b to the chamber 16 of the second segment 6B. Second temperature adjusting means 52 to be supplied.

  The heat medium 45 (the first heat medium 45a and the second heat medium 45b) is not particularly limited as long as it can heat the core body 2. As the heat medium of this embodiment, a high-temperature fluid (especially, steam that is easy to handle) is employed.

  The first temperature adjusting means 51 includes a first heat medium supplying means 51a for supplying a first heat medium 45a to the chamber 15 of each first segment 6A, and a first heat medium supplied to the chamber 15 of each first segment 6A. A first heat medium discharging means 51b for discharging 45a, and a first heat medium heating means 51c for heating the first heat medium 45a between the first heat medium supplying means 51a and the first heat medium discharging means 51b, It is comprised including.

  FIG. 5 is an explanatory diagram of the first heat medium supply means 51a. In FIG. 5, the first heat medium discharging means 51b and the second temperature adjusting means 52 shown in FIG. 1 are omitted. As shown in FIGS. 1 and 5, the first heat medium supply means 51a includes a plurality of supply ports 53 connectable to the first connection ports 21 of the first segments 6A, and the first heat medium heating means 51c. The distribution part 54 which distributes the 1st heat medium 45a supplied from to each supply port 53 is included.

  Each supply port 53 is provided in a bead ring 42 a (shown in FIG. 1) of the vulcanization mold 42. Each supply port 53 is connected to each first connection port 21 when the core body 2 is put into the vulcanization mold 42, and supplies the first heat medium 45a to the first chamber portion 15a. For connection between the supply port 53 and the first connection port 21, it is desirable to employ an automatic detachable connector pair having safety valves that can be automatically detachable from each other. Such an automatic detachable connector pair can supply the heat medium 45 only at the time of connection, so that safety can be improved.

  The distribution unit 54 is disposed outside the vulcanization mold 42. The distribution unit 54 is provided with a space 54a to which the first heat medium 45a is supplied. Further, the same number of holes 54b as the supply ports 53 (five in this embodiment) are provided in the distribution unit 54 at equal intervals. Each hole 54b and each supply port 53 are connected to each other by, for example, a heat-resistant hose 55 or the like. Thereby, the distribution part 54 can distribute the 1st heat medium 45a supplied to the space 54a equally to each supply port 53, and can supply it to the 1st chamber part 15a of each 1st segment 6A. Therefore, the 1st temperature control means 51 can supply the 1st heating medium 45a of the same temperature to the 1st chamber part 15a of each 1st segment 6A, respectively, and can heat each 1st segment 6A equally. . The first heat medium 45a supplied to each first chamber portion 15a is guided to each second chamber portion 15b through the partition plate 18.

  FIG. 6 is an explanatory diagram of the first heat medium discharging means 51b. In FIG. 6, the first heat medium supply means 51a and the second temperature adjustment means 52 shown in FIG. 5 are omitted. As shown in FIGS. 1 and 6, the first heat medium discharging means 51b includes a discharge port 56 connectable to the second connection port 22 of each first segment 6A, and a first discharge discharged from each first segment 6A. 1 heat collecting medium 45a is collected.

  Each discharge port 56 is arranged in the bead ring 42 a of the vulcanization mold 42 side by side with the supply port 53 in the tire circumferential direction. Each discharge port 56 is connected to each second connection port 22 when the core body 2 is put into the vulcanization mold 42, and the first heat medium 45a in the second chamber portion 15b is discharged. In addition, it is desirable to employ an automatic detachable connector pair having safety valves that can be automatically detached from each other for the connection between the discharge port 56 and the second connection port 22.

  The aggregation part 57 is disposed outside the vulcanization mold 42. The concentrating part 57 is provided with a space 57a in which the first heat medium 45a is discharged. The same number of holes 57b as the discharge ports 56 (five in the present embodiment) are provided in the concentrating portion 57 at equal intervals. Each hole 57b and each discharge port 56 are connected to each other by, for example, a heat-resistant hose 58 or the like. Thereby, the aggregation part 57 can collect | recover the 1st heat medium 45a discharged | emitted from each discharge port 56. FIG.

  As shown in FIG. 1, the first heat medium heating means 51c of the present embodiment is configured by a boiler capable of heating the first heat medium 45a (steam). The first heat medium heating means 51c is disposed outside the vulcanization mold 42 in the same manner as the distribution part 54 of the first heat medium supply means 51a and the aggregation part 57 of the first heat medium discharge means 51b. The first heat medium heating means 51c is connected to the distribution part 54 of the first heat medium supply means 51a and the aggregation part 57 of the first heat medium discharge means 51b by a heat-resistant hose 59 or the like. Such a first heat medium heating means 51c supplies the heated first heat medium 45a to the distribution section 54 of the first heat medium supply means 51a and discharges it to the aggregation section 57 of the first heat medium discharge means 51b. The first heat medium 45a (steam drain) thus made can be recovered to the first heat medium heating means 51c.

  Further, the first temperature adjusting means 51 of the present embodiment is provided with a first control device 60 for adjusting the temperature of the first heat medium 45a. The first control device 60 is provided, for example, in the distribution unit 54 of the first heat medium supply means 51a. This 1st control apparatus 60 adjusts the flow volume and pressure of the steam supplied from the 1st heat-medium heating means 51c (boiler). For example, the first control device 60 is configured to adjust the deviation between the temperature of the first heat medium 45a collected in the aggregation unit 57, the hose 58, and the like and a preset temperature. The flow rate and pressure of 45a (steam) are adjusted. The first control device 60 is preferably connected so as to be controllable by a computer device (not shown), for example.

  Similarly to the first temperature adjusting means 51, the second temperature adjusting means 52 includes a second heat medium supplying means 52a for supplying the second heat medium 45b to the chamber 16 of each second segment 6B, and each second segment 6B. The second heat medium discharging means 52b for discharging the first heat medium 45a supplied to the chamber 16 and the second heat medium 45b between the second heat medium supplying means 52a and the second heat medium discharging means 52b. And a second heat medium heating means 52c for heating.

  The second heat medium supply means 52a includes a plurality of supply ports 63 connectable to the first connection ports 25 of the second segments 6B and the second heat medium 45b supplied from the second heat medium heating means 52c. The distribution part 64 distributed to each supply port 63 is included. Each supply port 63 and the distribution part 64 are set to the same structure as each supply port 53 and the distribution part 54 of the 1st temperature control means 51 shown in FIG. Thus, the second heat medium supply means 52a distributes the second heat medium 45b supplied to the distribution unit 64 evenly to the supply ports 63, and supplies the second heat medium 45b to the first chamber unit 16a of each second segment 6B. can do. Accordingly, the second temperature adjusting means 52 can supply the second heat medium 45b of the same temperature to the first chamber portion 16a of each second segment 6B, respectively, and heat each second segment 6B evenly. .

  The second heat medium discharge means 52b collects a plurality of discharge ports 66 connectable to the second connection ports 26 of the second segments 6B and the second heat medium 45b discharged from the second segments 6B. Part 67. Each discharge port 66 and the aggregation part 67 are set to the same structure as each discharge port 56 and the aggregation part 57 of the 2nd temperature control means 52 shown in FIG. Thereby, the 2nd heat medium discharge means 52b can collect | recover the 2nd heat medium 45b discharged | emitted from the 2nd chamber part 15b of each 2nd segment 6B to the aggregation part 67. FIG.

  The second heat medium heating means 52c is set to have the same configuration as the first heat medium heating means 51c. Such a second heat medium heating means 52c supplies the heated second heat medium 45b (steam) to the distribution section 64 of the second heat medium supply means 52a, and at the same time, the aggregation section of the second heat medium discharge means 52b. The second heat medium 45b (steam drain) discharged to 67 can be recovered.

  Furthermore, the second temperature adjusting means 52 of the present embodiment is provided with a second control device 70 that adjusts the temperature of the second heat medium 45b. The second control device 70 is set to the same configuration as the first control device 60 and is provided in the distribution unit 64. Thereby, the 2nd temperature adjustment means 52 can control the temperature of the 2nd heat medium 45b independently of the 1st heat medium 45a.

  As described above, in the rigid core device 1 of the present embodiment, the first temperature adjusting means 51 and the second temperature adjusting means 52 cause the temperature to increase according to the temperature rise characteristics of the first segments 6A and the second segments 6B. The first heat medium 45a and the second heat medium 45b that are different from each other can be supplied to each. For example, the second temperature adjusting unit 52 adjusts the temperature of the second heat medium 45b so that the temperature difference between the first segment 6A and the second segment 6B is within a predetermined range (for example, the first segment 6A). The second heat medium 45b heated higher than the temperature of the first heat medium 45a can be supplied to the second segment 6B). Thereby, the 2nd segment 6B can equalize | homogenize the temperature of 1st segment 6A and 2nd segment 6B, and is useful for manufacturing the tire T without a vulcanization nonuniformity.

  In addition, the range of the temperature difference between the first segment 6A and the second segment 6B can be set as appropriate. If the temperature difference exceeds 15 ° C., it may be difficult to uniformly vulcanize the raw tire Tn. For this reason, the range of the temperature difference is preferably 10 ° C. or less, more preferably 5 ° C. or less.

  It is desirable that the first temperature adjusting means 51 and the second temperature adjusting means 52 can be switched to each other only by changing the temperature settings of the first control device 60 and the second control device 70, for example. This eliminates the need to always connect the first segment 6A and the second segment 6B to the same first temperature adjusting means 51 and second temperature adjusting means 52, so the core body 2 is attached to the vulcanizing mold 42. It is possible to simplify the control (procedure) when doing so.

  As shown in FIG. 3, the rigid core device 1 is preferably provided with a temperature sensor 71 that measures the temperature of the segment 6. Since such a temperature sensor 71 can adjust the first heat medium 45a and the second heat medium 45b based on the temperature of the segment 6, the temperature of the first segment 6A and the second segment 6B is made uniform. To help. As the temperature sensor 71, for example, a thermocouple or the like is desirable.

  Note that the first segment 6A, which shows a rapid temperature increase tendency, quickly rises to substantially the same temperature as the first heat medium 45a. For this reason, the temperature of the first heat medium 45a can be regarded as the temperature of the first segment 6A after a lapse of a certain time from the start of heating. The “certain time” is set in advance by an experiment using the first segment 6A and the first heat medium 45a.

  On the other hand, unlike the first segment 6A, it is difficult to grasp the temperature of each second segment 6B showing a gradual rise in temperature. From such a viewpoint, it is desirable that the temperature sensor 71 is provided only in the second segment 6B that shows a gradual temperature rise tendency. Thereby, since the temperature of the 2nd segment 6B can be grasped | ascertained accurately, it is useful for equalizing the temperature of the 1st segment 6A and the 2nd segment 6B. In the present embodiment, since it is not necessary to provide the temperature sensor 71 in the first segment 6A, the structure of the rigid core device 1 can be simplified while the number of the temperature sensors 71 is reduced. Therefore, in the rigid core device 1 of the present embodiment, the manufacturing cost can be suppressed.

  Since each second segment 6B is equally supplied with the second heat medium 45b having the same temperature by the second temperature adjusting means 52, the temperature of each second segment 6B becomes substantially the same. For this reason, it is desirable that the temperature sensor 71 is provided only in one second segment 6B selected from the plurality of second segments 6B. Thereby, since the structure of the rigid core device 1 can be further simplified while further reducing the number of the temperature sensors 71, the manufacturing cost can be significantly suppressed.

  It is desirable that the temperature sensor 71 is provided in a portion where the temperature rise is slowest in the second segment 6B. Thereby, the temperature sensor 71 can accurately measure the temperature of the second segment 6B. The temperature sensor 71 of the present embodiment is desirably disposed in the vicinity of the one split surface 6b in the tire circumferential direction of the second segment 6B and the tread molding surface portion Sa. The term “near” refers to a region whose distance from the dividing surface 6b and the tread molding surface portion Sa is within 20 mm.

  The temperature sensor 71 is, for example, the second segment 6 </ b> B when the core body 2 is put into the vulcanization mold 42 (shown in FIG. 1), as in the patent document (Japanese Patent Laid-Open No. 2013-6366). A sensor connector (not shown) provided on the sensor and a sensor connection terminal (not shown) provided on the vulcanizing mold 42 are detachably electrically connected. The sensor connection terminal unit is connected to, for example, a computer device (not shown) that controls the first control device 60 and the second control device 70. Thereby, the 2nd control apparatus 70 can adjust the temperature of the 2nd heating medium 45b based on the temperature of the 2nd segment 6B.

  Next, an example of a method for manufacturing the tire T using the rigid core device 1 will be described. In this manufacturing method, first, as shown in FIG. 1, step S <b> 1 for forming a raw tire Tn on the outside of the core body 2 is performed. In this step S1, tire constituent members such as an inner liner, a carcass ply, a belt ply, a sidewall rubber, and / or a tread rubber are sequentially attached onto the outer surface S of the core body 2. As a result, an unvulcanized green tire Tn is formed on the outer surface S of the core body 2.

  Next, a vulcanization step S2 for vulcanizing the raw tire Tn together with the core body 2 is performed. FIG. 7 is a cross-sectional view showing the core body 2 and the vulcanization mold 42 during vulcanization. In the vulcanization step S2, the raw tire Tn is vulcanized and molded together with the vulcanization mold 42 by putting the raw tire Tn together with the core body 2 into the vulcanization mold 42. After the vulcanization molding, the tire T and the core body 2 are taken out from the vulcanization mold 42. And the tire T can be manufactured by taking out the core main body 2 from the inner cavity of the tire T.

  In the vulcanization step S2, when the core body 2 is put into the vulcanization mold 42, as shown in FIGS. 1 and 5, each supply port 53 of the first temperature adjusting means 51 and the first segment Each first connection port 21 of 6A is connected. Moreover, as FIG.1 and FIG.6 shows, each discharge port 56 of the 1st temperature control means 51 and each 2nd connection port 22 of 1st segment 6A are connected. Further, as shown in FIG. 1, the supply port 63 of the second temperature adjustment means 52 and the first connection port 25 of the second segment 6 </ b> A are connected, and the discharge port 66 of the second temperature adjustment means 52. The second connection port 26 of the second segment 6A is connected. Further, a sensor connector (not shown) of the temperature sensor 71 (shown in FIG. 3) and a sensor connection terminal portion (not shown) provided on the vulcanizing mold 42 are connected.

  In the vulcanization step S2, the first heating medium 45a is supplied to the first segment 6A to heat the first segment 6A, and the second heating medium 45b is supplied to the second segment 6B. The second step S22 for heating the two segments 6B is performed. In this embodiment, 1st process S21 and 2nd process S22 are implemented simultaneously.

  In the first step S21, as shown in FIGS. 1 and 5, the first heat medium 45a heated to a predetermined temperature by the first heat medium heating means 51c is replaced by the first heat medium supply means 51a. It is supplied to the distribution unit 54. The first heat medium 45a supplied to the distribution unit 54 is guided from the holes 54b to the supply ports 53 of the first heat medium supply means 51a through the hose 55. The first heat medium 45a guided to each supply port 53 is guided to the first chamber portion 15a of each first segment 6A through the first connection port 21.

  The first heat medium 45a guided to the first chamber portion 15a is guided to the second chamber portion 15b while heating the first segment 6A, and the first heat medium 45a is guided from the second connection port 22 as shown in FIG. It is discharged to the discharge port 56 of the medium discharge means 51b. As shown in FIGS. 1 and 6, the first heat medium 45a discharged to each discharge port 56 is recovered by the first heat medium heating means 51c via the concentrating portion 57 of the first heat medium discharge means 51b. Is done. The first heat medium 45a recovered by the first heat medium heating means 51c is reheated by the first heat medium heating means 51c and supplied to the distribution unit 54 of the first heat medium supply means 51a.

  Thus, in 1st process S21, the 1st segment 6A can be made to supply the 1st heating medium 45a, and each 1st segment 6 can be heated effectively. In the present embodiment, the first heat medium 45a is controlled to a predetermined temperature by the first controller 60. Thereby, since the 1st heating medium 45a of fixed temperature is stably supplied to each 1st segment 6A, each 1st segment 6A can be heated effectively.

  In the second step S22, as shown in FIG. 1, the second heat medium 45b heated to a predetermined temperature by the second heat medium heating means 52c is replaced by the distributor 64 of the second heat medium supply means 52a. To be supplied. The second heat medium 45b supplied to the distribution unit 64 is guided to each supply port 63 of the second heat medium supply means 52a from each hole (not shown) of the distribution unit 64 via the hose 68. The second heat medium 45b guided to each supply port 63 is guided to the first chamber portion 16a (shown in FIG. 3) of each second segment 6A via the first connection port 25.

  The second heat medium 45b guided to the first chamber portion 16a is guided to the second chamber portion 16b (shown in FIG. 3) while heating the second segment 6A, and the second heat medium is discharged from the second connection port 26. It is discharged to the discharge port 66 of the means 52b. The second heat medium 45b discharged to each discharge port 66 is recovered by the second heat medium heating means 52c via the aggregation portion 67 of the second heat medium discharge means 52b. The second heat medium 45b recovered by the second heat medium heating means 52c is reheated by the second heat medium heating means 52c and supplied to the distribution unit 64 of the second heat medium supply means 52a. Thus, in 2nd process S22, the 2nd heating medium 45b can be supplied to the 2nd segment 6B, and the 2nd segment 6B can be heated effectively.

  In the second step S22, the temperature of the second heat medium 45b is controlled by the second controller 70 independently of the first heat medium 45a. Thereby, in vulcanization process S2, the 1st heat carrier 45a or the 2nd heat carrier 45b can be supplied to each according to the temperature rise characteristic of the 1st segment 6A and the 2nd segment 6B.

  As described above, the first segment 6A exhibits a rapid temperature rising tendency as a relative one. On the other hand, the 2nd segment 6B shows a moderate temperature rise tendency as a relative thing. For this reason, when the heat medium 45a, 45b of the same temperature is supplied to the first segment 6A and the second segment 6B as in the conventional vulcanization step S2, the temperature of the first segment 6A and the second segment 6B The difference is likely to increase. Such a temperature difference prevents uniform vulcanization of the raw tire Tn.

  In the second step S22 of the present embodiment, the temperature of the second heat medium 45b is adjusted so that the temperature difference between the first segment 6A and the second segment 6B is within a predetermined range. Note that, as described above, the temperature of the first segment 6A can be regarded as the same as the temperature of the first heat medium 45a after a certain time has elapsed since the start of heating. The temperature of the second segment 6B is measured by the temperature sensor 71. A temperature difference between the first segment 6A and the second segment 6B is obtained from the temperature of the first segment 6A and the temperature of the second segment 6B. Such a temperature difference calculation is performed by, for example, a computer device (not shown) that controls the first control device 60 and the second control device 70.

  In the second step S22, when the temperature difference between the first segment 6A and the second segment 6B is outside a predetermined range, the second temperature adjusting means 52 causes the temperature of the first segment 6A to be higher than that of the first heat medium 45a. The high second heat medium 45b is supplied to the second segment 6B. Thereby, the temperature of the 2nd segment 6B can be raised early, and the temperature difference of 6 A of 1st segments and the 2nd segment 6B can be set to the predetermined range.

  On the other hand, when the temperature difference between the first segment 6A and the second segment 6B is within a predetermined range, it is not necessary to heat the second segment 6B more than the first segment 6A. For this reason, the second heat medium 45b set to the same temperature as the first heat medium 45a is supplied to the second segment 6B by the second temperature adjusting means 52. Thereby, it is possible to prevent the temperature of the second segment 6B from becoming higher than the temperature of the first segment 6A.

  The second step S22 in which the temperature of the second heat medium 45b is adjusted is repeatedly performed while the vulcanization step S2 is performed. For this reason, in 2nd process S22, the temperature of each segment 6A, 6B can be equalized, and the raw tire Tn can be vulcanized | cure uniformly by extension.

  As mentioned above, although especially preferable embodiment of this invention was explained in full detail, this invention is not limited to embodiment of illustration, It can deform | transform and implement in a various aspect.

  A rigid core device having the basic structure shown in FIGS. 1 to 3 and having first temperature adjusting means and second temperature adjusting means was manufactured (Example). A green tire was formed outside the core body of the rigid core device of the example, and the green tire was put together with the core body into a vulcanization mold and vulcanized.

  In the vulcanization process of the example, based on the temperature of the second segment measured by the temperature sensor, as shown in the graph shown in FIG. 8A, the temperature is controlled independently of the first heating medium. Two heating media were supplied to the second segment. And about eight tires manufactured based on such a process, it was confirmed visually whether there was any vulcanization nonuniformity.

  For comparison, a rigid core device having the basic structure shown in FIGS. 1 to 3 and having no first temperature adjusting means and no second temperature adjusting means was manufactured (comparative example). A green tire was formed outside the core body of the rigid core device of the comparative example, and this green tire was put together with the core body into a vulcanization mold and vulcanized.

In the vulcanization process of the comparative example, the heat medium having the same temperature was supplied to the first segment and the second segment. FIG. 8B shows a graph showing the relationship between the temperature of the heat medium and the second segment of the comparative example and the vulcanization time. And about two tires manufactured based on such a process, it was confirmed visually whether there was vulcanization nonuniformity. The common specifications are as follows.
Core body:
1st segment: 5 2nd segment: 5 1st, 2nd control device: Intelligent pressure sensor switch (SPS300) made by Azbil Corporation
Tire size: 275 / 40RF18

  As a result of the test, as shown in FIGS. 8A and 8B, the second segment of the example can effectively increase the temperature compared to the second segment of the comparative example. The temperature of the segment and the temperature of the second segment could be made uniform at an early stage. Further, among the tires (eight tires) of the example, vulcanization unevenness occurred in one tire. On the other hand, among the tires of the comparative example (two), vulcanization unevenness occurred in two. Therefore, in the manufacturing method using the rigid core device of the example, it was confirmed that the green tire can be vulcanized uniformly as compared with the manufacturing method of the comparative example.

DESCRIPTION OF SYMBOLS 1 Rigid core apparatus 2 Core main body 3 Temperature control means 6A 1st segment 6B 2nd segment 15 Chamber 16 Chamber 45a 1st heat medium 45b 2nd heat medium 51 1st temperature control means 52 2nd temperature control means

Claims (8)

A rigid core device for manufacturing a pneumatic tire, including a core body that is formed into an annular shape by arranging a plurality of segments in a tire circumferential direction, and temperature adjusting means for heating the core body,
The segment includes a first segment and a second segment having a temperature rise characteristic different from that of the first segment, and a chamber through which a heating medium enters and exits is provided inside each segment.
The shape of the first segment is different from the shape of the second segment,
The chamber of the first segment has substantially the same shape as the chamber of the second segment;
The temperature adjusting means includes
First temperature adjusting means for supplying a first heat medium to the chamber of the first segment;
A rigid core device comprising: a second temperature adjusting means for supplying a second heat medium capable of temperature control independently of the first heat medium to the chamber of the second segment.   2. The medium according to claim 1, wherein the second temperature adjusting unit adjusts the temperature of the second heat medium so that a temperature difference between the first segment and the second segment is within a predetermined range. Child device. The segment includes a plurality of the first segments and a plurality of second segments,
The first temperature adjusting means supplies the first heat medium having the same temperature to the first segments,
The rigid core device according to claim 1 or 2, wherein the second temperature adjusting means supplies the second heat medium having the same temperature to the second segments. The rigid core device according to any one of claims 1 to 3 , wherein the chamber of each segment is provided independently. The rigid core device according to any one of claims 1 to 4 , wherein the chamber of the first segment includes a pair of first side wall portions extending along split surfaces at both ends in the tire circumferential direction of the first segment. The rigid core device according to any one of claims 1 to 5 , wherein the chamber of the first segment and the chamber of the second segment are each formed in a rectangular parallelepiped shape. A method for manufacturing a pneumatic tire using a core body that is formed by arranging a first segment and a second segment having different temperature rise characteristics and shapes in a tire circumferential direction,
Inside the first segment and the second segment are provided chambers of substantially the same shape through which the heating medium enters and exits,
Forming a green tire on the outside of the core body;
Vulcanizing the raw tire together with the core body,
The vulcanization process includes
Supplying a first heat medium to the chamber of the first segment to heat the first segment;
And a second step of supplying a temperature-controlled second heating medium independently of the first heating medium to the chamber of the second segment. The pneumatic tire according to claim 7 , wherein in the second step, the temperature of the second heating medium is adjusted so that a temperature difference between the first segment and the second segment is within a predetermined range. Production method.

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