Piping structure of tire vulcanizer, circulator, and method for vulcanizing tire with tire vulcanizer

Abstract

An example of a piping structure of a tire vulcanizer to which the present invention is applied has a central mechanism 1 of the tire vulcanizer as illustrated in FIG. 1. The central mechanism 1 has a bug head 2, a hydraulic cylinder 3, and exhaust circulation path pipes 4. In addition, the central mechanism 1 has a bladder (not illustrated) which may be expanded and contracted as a vulcanizing medium is supplied into the bladder. One end of the exhaust circulation path pipe 4 is connected to an interior of the bladder, and the two exhaust circulation path pipes 4 are connected to each other through a bypass pipe 5. The other end of the exhaust circulation path pipe 4 is connected to an exterior of the central mechanism 1.

Claims

1. A piping structure of a tire vulcanizer, the piping structure comprising: a medium supply path which communicates with an interior of a bladder for heating and pressing a raw tire, and supplies a high-temperature and high-pressure fluid into the bladder; a medium discharge path which communicates with the interior of the bladder, and forms a circulation path for gas between the interior of the bladder and the medium discharge path, and discharges the gas to the outside; and a circulator which is provided on the medium discharge path, and circulates the gas in the circulation path when the raw tire is vulcanized by the bladder, wherein the medium discharge path includes exhaust pipes, and a bypass pipe connecting with the exhaust pipes, wherein the exhaust pipes discharge the gas to the outside, wherein the circulator is provided in the bypass pipe and wherein the circulator is not directly disposed in the medium supply path, and wherein the circulator switches a direction of the circulation of gas in the circulation path to a forward or reverse direction.

2. The piping structure of claim 1, the piping structure further comprising a supply nozzle connected to the bladder, wherein a diameter of the supply nozzle is up to 2 mm.

3. A circulator provided on a medium discharge path, wherein the circulator is provided in a bypass such that a circulation path for gas is formed between the medium discharge path and an interior of a bladder for heating and pressing a raw tire and for discharging the gas to the outside, wherein the circulator circulates the gas in the circulation path when the raw tire is vulcanized by the bladder, and wherein the medium discharge path includes exhaust pipes, wherein the bypass connects with the exhaust pipes, wherein the exhaust pipes discharge gas to the outside, and wherein the circulator is not directly disposed on a medium supply path, wherein the circulator is configured to switch a direction of the circulation path of gas from a first direction to a second direction and from the second direction to the first direction, and wherein the first direction is opposite to the second direction.

4. A method of vulcanizing a tire with a tire vulcanizer wherein the tire vulcanizer includes a piping structure, wherein the piping structure includes a medium discharge path which communicates with an interior of a bladder to form a circulation path for gas, and wherein the medium discharge path includes at least two exhaust pipes that discharge the gas outside, a circulator to circulate the gas, and a bypass pipe connecting with the at least two exhaust pipes and the circulator wherein the circulator is provided in the bypass pipe and wherein the circulator is not directly disposed on a medium supply path, the method comprising: supplying a high-temperature and high-pressure fluid into the bladder for heating and pressing a raw tire; and circulating the gas in the circulation path for the gas which is formed between the medium discharge path for the gas and the interior of the bladder when the raw tire is vulcanized by the bladder.

Description

DESCRIPTION OF DRAWINGS

(1) FIG. 1 is a schematic front view of a piping structure of a tire vulcanizer to which the present invention is applied.

(2) FIG. 2 is a schematic side view of the piping structure of the tire vulcanizer to which the present invention is applied.

(3) FIG. 3 is a schematic view of a peripheral structure of a supply port (FIG. 3A), a schematic view of a connection portion between an exhaust circulation path pipe and a bladder (FIG. 3B), and a schematic view of supply, discharge, and circulation paths for a vulcanizing medium (FIG. 3C).

(4) FIG. 4 is a graph illustrating a change in temperature in upper and lower bladders when using a piping structure in the related art in which a diameter of a supply nozzle for supplying a vulcanizing medium into a bladder is small and a circulator is not used.

(5) FIG. 5 is a graph illustrating a change in temperature in the upper and lower bladders when using the piping structure in the related art in which a diameter of the supply nozzle for supplying the vulcanizing medium into the bladder is a diameter that does not hinder the circulation of the medium caused by the circulator and the circulator is used.

(6) FIG. 6 is a graph illustrating a change in temperature in upper and lower bladders when using an example of a piping structure of the present invention in which a diameter of a supply nozzle for supplying a vulcanizing medium into a bladder is small and a circulator is used.

(7) FIG. 7 is a schematic view illustrating a piping structure of a tire vulcanizer in the related art.

(8) FIG. 8 is a schematic view illustrating the piping structure of the tire vulcanizer in the related art.

BEST MODE

(9) Hereinafter, an exemplary embodiment of the present invention will be described with reference to the drawings and used to understand the present invention.

(10) FIG. 1 is a schematic front view of a piping structure of a tire vulcanizer to which the present invention is applied. FIG. 2 is a schematic side view of the piping structure of the tire vulcanizer to which the present invention is applied. Further, a structure to be described below is an example of the present invention, and the contents of the present invention are not limited thereto.

(11) An example of the piping structure of the tire vulcanizer to which the present invention is applied has a central mechanism 1 of the tire vulcanizer as illustrated in FIG. 1. The central mechanism 1 has a bug head 2, a hydraulic cylinder 3, and exhaust circulation path pipes 4. In addition, the central mechanism 1 has a bladder (not illustrated) which may be expanded and contracted as a vulcanizing medium is supplied into the bladder.

(12) The bug head 2 has a plurality of supply ports for the vulcanizing medium, and is disposed at an upper portion of the central mechanism 1. In addition, the hydraulic cylinder 3 is fixed at a lower portion of the bug head 2.

(13) One end of the exhaust circulation path pipe 4 is connected to an interior of the bladder, and the two exhaust circulation path pipes 4 are connected to each other through a bypass pipe 5. The other end of the exhaust circulation path pipe 4 is connected to an exterior of the central mechanism 1. In addition, a circulator 6, which circulates the vulcanizing medium while maintaining pressure in the bladder, is provided in the bypass pipe 5.

(14) The interior of the bladder, the exhaust circulation path pipes 4, and the bypass pipe 5 define a circulation path, and the vulcanizing medium may be circulated in the circulation path by the circulator 6 when a raw tire is vulcanized. In addition, after the vulcanization, the vulcanizing medium in the bladder flows toward the other end of the exhaust circulation path pipe 4, and then is discharged to the outside (see arrows indicated by symbol Z in FIG. 1).

(15) In addition, the circulator 6 may switch a direction of a flow when the circulator 6 circulates the vulcanizing medium. Therefore, circulation efficiency may be changed accordingly.

(16) A center post-rod 7 and a piston 8 are integrally disposed in the hydraulic cylinder 3. The center post-rod 7 and the piston 8 constitute a driving mechanism which is moved in the hydraulic cylinder 3 by a hydraulic operation and changes a height position of the central mechanism 1 during the process of vulcanizing the raw tire.

(17) Here, the bug head 2 need not necessarily have the plurality of supply ports. However, the bug head 2 may particularly have the plurality of supply ports because a proper use is enabled in accordance with the types of vulcanizing media and general-purpose properties of the tire vulcanizer are increased.

(18) In addition, the circulation path for the vulcanizing medium need not necessarily be configured by the two exhaust circulation path pipes 4, the bypass pipe 5, and the interior of the bladder, and it will be acceptable if the medium may be circulated at a position independent of a supply path for the vulcanizing medium and the vulcanizing medium may be discharged to the outside of the tire vulcanizer. In addition, for example, a structure in which the number of exhaust circulation path pipes 4 is increased or a structure in which a combination of the exhaust circulation path pipes 4 and the bypass pipe 5 is separately provided and connected may be adopted.

(19) FIG. 2 illustrates a state of the central mechanism 1 illustrated in FIG. 1 when viewed in a direction rotated by about 90 degrees. As illustrated in FIG. 2, the central mechanism 1 has supply holes 10 provided in cylinder guides 9. The vulcanizing medium is supplied to the supply holes 10 from a non-illustrated vulcanizing medium supply source, and the vulcanizing medium is supplied to the supply ports of the bug head 2 through hoses.

(20) The plurality of supply ports is provided in the bug head 2, such that the vulcanizing medium such as steam or nitrogen may be supplied into the bladder in accordance with the type of vulcanizing media.

(21) FIG. 3 is a schematic view of a peripheral structure of the supply port (FIG. 3A), a schematic view of a connection portion between the exhaust circulation path pipe and the bladder (FIG. 3B), and a schematic view of supply, discharge, and circulation paths for the vulcanizing medium (FIG. 3C).

(22) As illustrated in FIG. 3A, the vulcanizing medium is supplied to the supply ports 11 through the supply holes 10 in the cylinder guides 9 and the hoses. In addition, supply nozzles 12 are provided at portions where the bug head 2 is connected to the bladders. A diameter of the supply nozzle 12 is 2 mm, and as the diameter is decreased, an effect of promoting convection of the vulcanizing medium in the bladder is increased. Further, the arrows indicated by symbol Y in FIG. 3A indicate directions in which the vulcanizing medium is supplied.

(23) As illustrated in FIG. 3B, a medium supply and discharge hole 13 and a medium supply and discharge hole 14 are formed at connection portions where the exhaust circulation path pipes 4 and the bladders are connected. The medium supply and discharge hole 13 and the medium supply and discharge hole 14 are portions that are intake ports in the discharge direction when the vulcanizing medium, which has been supplied into the bladder, is discharged toward the exhaust circulation path pipe 4. Further, the arrows indicated by symbol X in FIG. 3B indicate directions in which the vulcanizing medium is discharged when the vulcanizing medium is discharged.

(24) In addition, when the circulator 6 circulates the vulcanizing medium in the bladder, the medium supply and discharge hole 13 a feeding port that supplies the medium, which flows through the bypass pipe 5 and the exhaust circulation path pipe 4, into the bladder. In addition, when the medium is discharged from the interior of the bladder toward the exhaust circulation path pipe 4, the medium supply and discharge hole 14 is an intake ports in the discharge direction.

(25) As illustrated in FIG. 3C, there is a structure in which a supply path for the vulcanizing medium, which is indicated by reference numeral 15, and a circulation path indicated by reference numeral 16, are provided with respect to the bladder. When vulcanizing the raw tire, the vulcanizing medium is circulated by the circulator 6 in an arrow direction indicated by symbol C.

(26) An effect in respect to temperatures of upper and lower portions of the bladder in a case in which the piping structure of the tire vulcanizer described above is used will be described.

(27) FIG. 4 is a graph illustrating a change in temperature in upper and lower bladders when using a piping structure in the related art in which a diameter of a supply nozzle for supplying a vulcanizing medium into a bladder is small and a circulator is not used.

(28) FIG. 5 is a graph illustrating a change in temperature in the upper and lower bladders when using the piping structure in the related art in which a diameter of the supply nozzle for supplying the vulcanizing medium into the bladder is a diameter that does not hinder the circulation of the medium caused by the circulator and the circulator is used.

(29) FIG. 6 is a graph illustrating a change in temperature in upper and lower bladders when using an example of the piping structure of the present invention in which a diameter of the supply nozzle for supplying the vulcanizing medium into the bladder is small and the circulator is used.

(30) FIGS. 4 to 6 are graphs in which a horizontal axis indicates the time (t), and a vertical axis indicates temperatures (T) of the upper bladder and the lower bladder. In addition, the respective graphs are illustrated for each set of the upper bladder and the lower bladder. In more detail, an upper bladder 17 and a lower bladder 18 are indicated by solid lines, an upper bladder 19 and a lower bladder 20 are indicated by dotted lines, and an upper bladder 21 and a lower bladder 22 are indicated by alternate long and short dashes lines. In addition, because drain is collected at the lower bladder, a temperature in the lower bladder is lower than that in the upper bladder.

(31) As described above, regarding a temperature in the bladder, a temperature difference between the upper bladder and the lower bladder needs to be small when vulcanizing the raw tire. In a case in which a temperature difference between the upper and lower bladders is decreased in a short time, efficiency in vulcanizing the raw tire is improved, and quality of the finished tire is improved.

(32) As illustrated in FIG. 4, in a case in which a small supply nozzle of which the nozzle diameter is about 2 mm is used without using the circulator, the vulcanizing medium may be vigorously blown to a position spaced apart from the nozzle in the bladder. As a result, for a predetermined time from the initiation of the vulcanization (in a region indicated by reference numeral 23), a temperature of the upper bladder 17 may be decreased, and a temperature of the lower bladder 18 may be increased, such that a temperature difference between the upper and lower bladders is decreased immediately after the initiation of the vulcanization (see symbol L1).

(33) Meanwhile, in a region indicated by reference numeral 24 in FIG. 4, a temperature difference between the upper and lower bladders is gradually decreased, and in the latter part of the vulcanization process, the supply nozzle hardly affects the temperature difference. At a time at a right end in the graph, a temperature difference between the upper and lower bladders is T1.

(34) In addition, in a case in which the circulator is used and a diameter of the supply nozzle is large to the extent to which the diameter does not hinder the circulation of the vulcanizing medium as illustrated in the graph in respect to the upper bladder 19 and the lower bladder 20 in FIG. 5, a temperature difference between the upper and lower bladders is not greatly decreased (see symbol L2) for a predetermined time from the initiation of the vulcanization (in a region indicated by reference numeral 23). Further, as a comparison object, FIG. 5 also illustrates a change in temperature of the upper bladder 17 and the lower bladder 18 illustrated in FIG. 4.

(35) Further, in a region indicated by reference numeral 24 in FIG. 5, the circulator continuously circulates the vulcanizing medium in the bladder, such that a temperature of the upper bladder 19 is greatly decreased, and a temperature difference between the upper and lower bladders is quickly decreased. Further, at a time at a right end in the graph, a temperature difference between the upper and lower bladders is T.sub.2, and a temperature difference is decreased (T.sub.1>T.sub.2) in comparison with the piping structure used in FIG. 4.

(36) FIG. 6 illustrates a result of using an example of the piping structure of the tire vulcanizer to which the present invention is applied. Further, as a comparison object, FIG. 6 also illustrates a change in temperature of the upper bladder 19 and the lower bladder 20 illustrated in FIG. 5.

(37) In the central mechanism 1, a diameter of the supply nozzle 12 is small, and as illustrated in FIG. 4, a temperature difference between the upper and lower bladders is decreased in a process in the former part after the initiation of the vulcanization indicated by reference numeral 23. In addition, in a region indicated by reference numeral 24, a temperature of the upper bladder 21 is greatly decreased, and a temperature difference between the upper and lower bladders is quickly decreased, as illustrated in FIG. 5.

(38) That is, in the piping structure of the tire vulcanizer to which the present invention is applied, a temperature difference between the interiors of the upper and lower bladders is efficiently decreased in the regions indicated by reference numerals 23 and 24, and reaches a portion indicated by reference numeral 25 at a temperature corresponding to T.sub.2 in FIG. 5.

(39) Since a temperature difference between the interiors of the upper and lower bladders is quickly decreased to a predetermined temperature difference, the time required to vulcanize the raw tire may be increased in a state in which the temperatures in the upper and lower bladders are uniform. In particular, when forming a tire having a small tire diameter, such as a tire for a passenger vehicle, the time required to vulcanize a single tire is short, and as a result, it is possible to greatly improve qualities of the tire or efficiency in manufacturing the tire.

(40) In addition, since the circulator is disposed in the path different from the supply path for the vulcanizing medium, a reverse flow of the vulcanizing medium from the supply path side does not occur.

(41) As described above, the piping structure of the tire vulcanizer according to the present invention is configured to realize efficient tire vulcanization.

(42) In addition, the circulator of the present invention is configured to realize efficient tire vulcanization.

(43) In addition, the method of vulcanizing a tire with the tire vulcanizer of the present invention is configured to realize efficient tire vulcanization.

DESCRIPTION OF MAIN REFERENCE NUMERALS OF DRAWINGS

(44) 1: Central mechanism

(45) 2: Bug head

(46) 3: Hydraulic cylinder

(47) 4: Exhaust circulation path pipe

(48) 5: Bypass pipe

(49) 6: Circulator

(50) 7: Center post-rod

(51) 8: Piston

(52) 9: Cylinder guide

(53) 10: Supply hole

(54) 11: Supply port

(55) 12: Supply nozzle

(56) 13: Medium supply and discharge hole

(57) 14: Medium supply and discharge hole

(58) 15: Supply path for vulcanizing medium

(59) 16: Circulation path

(60) 17: Upper bladder

(61) 18: Lower bladder

(62) 19: Upper bladder

(63) 20: Lower bladder

(64) 21: Upper bladder

(65) 22: Lower bladder

(66) 23: Region indicating predetermined time from initiation of vulcanization

(67) 24: Region of vulcanization process

(68) 25: Portion where temperature difference between upper and lower bladders is t.sub.2