JP6451135B2 - Pneumatic tire vulcanizer - Google Patents

Description

  The present invention relates to a vulcanizing apparatus for a pneumatic tire. More specifically, the vertical direction of injection of a heating medium and a pressure medium can be changed while having a simple configuration, and the vertical temperature difference of a vulcanizing bladder can be effectively reduced. The present invention relates to a vulcanizing apparatus for a pneumatic tire that can be reduced.

  A method of vulcanizing a green tire by inserting a vulcanization bladder into a green tire installed inside a mold and injecting steam (heating medium) and nitrogen gas (pressure medium) into the vulcanization bladder is known. . In this way, in the vulcanization method using steam and nitrogen gas, the specific gravity of nitrogen gas is larger than that of steam. Therefore, in the expanded vulcanization bladder, steam is present in a compressed state, and its Nitrogen gas is present below. For this reason, in the vulcanization bladder during vulcanization, the upper temperature becomes higher than the lower temperature, resulting in an upper and lower temperature difference. Due to this, the vulcanized tire has a problem that the degree of vulcanization varies greatly in the vertical direction when vulcanized.

  In order to solve such problems, various vulcanization methods and vulcanizers have been proposed (see, for example, Patent Documents 1 and 2). Patent Document 1 proposes a vulcanizer in which a stirring blade is installed inside a vulcanization bladder. In this vulcanizer, by rotating the stirring blade, steam inside the vulcanization bladder and nitrogen gas are stirred and mixed, and the difference in the upper and lower temperatures of the vulcanization bladder can be reduced. However, in this proposal, a stirring blade must be newly installed inside the vulcanization bladder. Along with this, there is a problem that the vulcanization equipment becomes complicated. If the vulcanization equipment becomes complicated, equipment failure is likely to occur. Therefore, it is preferable to use a simple equipment.

JP 2009-29035 A

  An object of the present invention is to provide a vulcanizing apparatus for a pneumatic tire that can change the vertical direction of injection of a heating medium and a pressure medium while having a simple configuration, and can effectively reduce the vertical temperature difference of the vulcanization bladder. There is to do.

In order to achieve the above object, a vulcanizing apparatus for a pneumatic tire according to the present invention includes a cylindrical vulcanizing bladder, a center post inserted vertically through the vulcanizing bladder, and the vulcanizing bladder supported by the center post. An upper clamp holding portion and a lower clamp holding portion for holding the upper and lower end portions, respectively, and an injection port arranged inside the vulcanization bladder at a position on the outer peripheral side of the center post . Connected to the injection line is a heating medium supplied through an injection line that extends downward from the middle in the vertical direction to the outside of the vulcanizing bladder and a pressure medium having a higher pressure and a higher specific gravity than the heating medium. by inflating the been the inlet by injecting into the vulcanization bladder, a pneumatic vulcanizing a green tire placed in a state horizontally inside the tire mold In the vulcanizing apparatus, two types of injection ports with different vertical directions in the injection direction are provided as the injection ports, and the two types are operated by operating the heating medium and the pressure medium in the injection line. A switching mechanism for opening and closing the injection port is disposed, a relatively upward injection port of the two types of injection ports is disposed at a position higher than a relatively downward injection port, and the switching mechanism is A valve body that includes a first valve portion and a second valve portion disposed above the first valve portion and is movable in the vertical direction by the pressure of the heating medium and the pressure medium inside the injection line; A biasing member for biasing the valve body downward is provided inside the injection line, and when the heating medium is supplied through the injection line , the valve body is biased by the pressure of the heating medium . By force member By against the bias direction by upward movement, the state of being opened the relatively downward inlet causes the closing of the relatively upward inlet by the second valve portion, through the inlet line When the pressurizing medium is supplied, the valve body is moved upward against the downward urging force of the urging member by the pressure of the pressurizing medium, and the first valve portion relatively moves downward. The inlet is closed, and the relatively upward inlet is opened .

  According to the present invention, two types of injection ports having different injection directions in the vertical direction are provided as the injection ports. When the heating medium is supplied through the injection line, the switching mechanism is operated by the pressure of the heating medium. In addition to closing the relatively upward inlet, the pressurized medium can be injected into the inside of the vulcanization bladder from the opened relatively downward inlet. In addition, when the pressurized medium is supplied through the injection line, the switching mechanism is operated by the pressure of the pressurized medium to close the relatively downward inlet and open the relatively upward inlet. The pressurized medium can be injected into the inside of the vulcanization bladder. In this way, by using the pressure difference between the heating medium and the pressure medium, the vulcanization bladder is heated by the heating medium and the pressure medium by changing the injection vertical direction of the heating medium and the pressure medium while having a simple configuration. The green tire G which is inflated and arranged in a horizontally placed state inside the tire mold can be vulcanized. Since the pressurized medium having a specific gravity larger than that of the heating medium moves from the upper side to the lower side inside the vulcanization bladder, the heating medium and the pressure medium are easily mixed, and the difference in the upper and lower temperatures of the vulcanization bladder is effectively reduced. Can be reduced. Thereby, since the dispersion | variation in the vulcanization degree of the vulcanized tire becomes small up and down, it leads also to the improvement of tire quality.

If the urging member for urging the valve body downward is provided , the pressure for opening and closing the two types of inlets can be easily adjusted only by changing the urging force by the urging member.

  The relatively downward injection port is set downward toward the outer peripheral side at an inclination angle of more than 0 ° and not more than 30 ° with respect to the horizontal direction, and the relatively upward injection port is set with respect to the horizontal direction. It can also be set as the structure set upward toward the outer peripheral side at an inclination angle of more than 0 ° and not more than 50 °. A plurality of the relatively downward inlets and the relatively upward inlets may be provided at equal intervals in the circumferential direction. The injection direction by the relatively downward inlet and the relatively upward inlet is set to intersect with the radial direction of the vulcanization bladder at an angle of 10 ° to 60 ° in plan view. It can also be configured. By adopting these configurations, it becomes easier to mix the heating medium and the pressure medium evenly inside the vulcanization bladder, and it becomes more and more advantageous to reduce the upper and lower temperature difference of the vulcanization bladder.

It is explanatory drawing which illustrates the whole outline | summary of the vulcanization | cure apparatus of the pneumatic tire of this invention by a longitudinal cross-sectional view. FIG. 2 is a partially enlarged view of FIG. 1. It is explanatory drawing which illustrates the state which the valve body of FIG. 2 moved upwards by a longitudinal cross-sectional view. It is explanatory drawing which illustrates the injection port and discharge port of FIG. 1 by planar view.

  Hereinafter, a vulcanizing apparatus for a pneumatic tire according to the present invention will be described based on an embodiment shown in the drawings.

  A pneumatic tire vulcanizing apparatus 1 (hereinafter referred to as a vulcanizing apparatus 1) of the present invention illustrated in FIGS. 1 to 4 includes a rubber tubular vulcanizing bladder 2. In the vulcanization bladder 2, a center post 4a constituting the center mechanism 4 is vertically inserted. The upper clamp part 3a and the lower clamp part 3b of the vulcanizing bladder 2 are held by a disc-shaped upper clamp holding part 5a and a lower clamp holding part 5b attached to the center post 4a, respectively.

  Two types of inlets 6 </ b> A and 6 </ b> B and an outlet 7 disposed in the vulcanization bladder 2 are provided at a position on the outer peripheral side of the center post 4 a. These injection ports 6A and 6B are different in the vertical direction of the injection direction, and are a relatively downward injection port 6A and a relatively upward injection port 6B. A heating medium M1 such as steam is injected into the inside of the vulcanization bladder 2 from one injection port 6A. A pressure medium M2 having a higher pressure and a higher specific gravity than the heating medium M1 is injected into the vulcanization bladder 2 from the other inlet 6B. For example, nitrogen gas is used as the pressurizing medium M2.

  The inlets 6A and 6B and the outlet 7 are connected to an inlet line 6L and an outlet line 7L that extend downward from the vulcanizer 1, respectively. The injection ports 6A and 6B are disposed at a position higher than the discharge port 7.

  In the injection line 6L, a switching mechanism 8 that is operated by the pressure of the heating medium M1 and the pressure medium M2 to open and close the two types of injection ports 6A and 6B is disposed. As illustrated in FIG. 2, in this embodiment, the relatively upward injection port 6 </ b> B is disposed at a position higher than the relatively downward injection port 6 </ b> A. The switching mechanism 8 includes a valve body 9 that can move in the vertical direction by the pressure of the heating medium M1 and the pressure medium M2 inside the injection line 6L. The valve body 9 includes a first valve portion 9a and a second valve portion 9b disposed above the first valve portion 9a.

  Further, an urging member 10 suspended from the upper end of the injection line 6L is attached to the upper end of the valve body 9. As the urging member 10, various springs such as a coil spring can be used. The valve body 9 is urged downward by the urging member 10. Magnets repelling each other arranged at the upper end of the valve body 9 and the upper end of the injection line 6L may be used as the biasing member 10.

  As illustrated in FIG. 2, when the heating medium M1 is supplied through the injection line 6L, the switching mechanism 8 is operated by the pressure of the heating medium M1 to open the relatively downward injection port 6A and relatively. The upward inlet 6B is closed. Specifically, a force to move upward acts on the valve body 9 by the pressure of the supplied heating medium M1, but the valve body 9 remains in a predetermined position by the downward biasing force by the biasing member 10. In this state, the second valve portion 9b closes the relatively upward inlet 6B. On the other hand, the 1st valve part 9a exists in the position below rather than the downward injection port 6A, and the injection port 6A will be in the open state.

  As illustrated in FIG. 3, when the pressurized medium M2 is supplied through the injection line 6L, the switching mechanism 8 is operated by the pressure of the pressurized medium M2 to open the relatively upward injection port 6B and perform the relative operation. Thus, the downwardly directed inlet 6A is closed. Specifically, a force to move upward acts on the valve body 9 by the pressure of the supplied pressurized medium M2, but the valve body 9 remains in a predetermined position by the downward biasing force by the biasing member 10. Since the pressurizing medium M2 has a higher pressure than the heating medium M1, the valve element 9 moves to a position above the state of FIG. 2 and stays at a predetermined position. In this state, the first valve portion 9a closes the relatively downward inlet 6A. On the other hand, the 1st valve part 9b exists in the position above the upward injection port 6B relatively upward, and the injection port 6B will be in the open state.

  For example, the relatively downward inlet 6A is set downward toward the outer peripheral side at an inclination angle A1 of more than 0 ° and not more than 30 ° with respect to the horizontal direction. For example, the relatively upward inlet 6B is set upward toward the outer peripheral side at an inclination angle A2 of more than 0 ° and not more than 50 ° with respect to the horizontal direction.

  Although the number of the relatively downward injection ports 6A and the number of the relatively upward injection ports 6B may be one, it is preferable to provide a plurality of them. It is preferable to provide a plurality of discharge ports 7 as well. In this embodiment, as illustrated in FIG. 4, four injection ports 6 </ b> A and 6 </ b> B are arranged at equal positions in the circumferential direction, and one discharge port 7 is arranged. The number of inlets 6 and outlets 7 can be set arbitrarily.

  The circumferential positions of the respective inlets 6A and 6B can be shifted from each other as illustrated in FIG. 4, but the circumferential positions can be the same. That is, the injection port 6B can be arranged at a position directly above the injection port 6A.

  In order to vulcanize the green tire G using the vulcanizing apparatus 1 of the present invention, first, the green tire G is placed in the mold 11 in a horizontally placed state. In this embodiment, the mold 11 includes an annular sector 11a divided into a plurality in the circumferential direction, an annular side plate 11b disposed on the upper side, and an annular side plate 11c disposed on the lower side. The vulcanization bladder 2 is inserted inside the green tire G, and the mold 11 is closed.

  Next, as illustrated in FIG. 2, the heating medium M1 is supplied through the injection line 6L. The switching mechanism 8 is operated by the pressure of the heating medium M1, and the heating medium M1 is injected into the vulcanizing bladder 2 through the one inlet 6A. Thereby, the vulcanizing bladder 2 is heated while being expanded.

  Next, as illustrated in FIG. 3, the pressurized medium M2 is supplied through the injection line 6L. The switching mechanism 8 is operated by the pressure of the pressurized medium M2, and the pressurized medium M2 is injected into the vulcanizing bladder 2 through the other injection port 6B. Thereby, the vulcanization bladder 2 is further expanded. The inner peripheral surface of the green tire G is pressed by the vulcanization bladder 2 expanded and heated by the heating medium M1 and the pressure medium M2 injected in this manner, and the green tire G is being pressed by the mold 11 accordingly. Heated.

  After the vulcanization time set in advance has elapsed, the heating medium M1 and the pressure medium M2 existing inside the vulcanization bladder 2 are discharged to the outside through the exhaust line 7L in a connected state. The upper side plate 11b is moved upward, and each sector 11a is moved in the diameter expansion direction to open the mold 11. Next, the vulcanized tire is moved upward and extracted from the vulcanized bladder 2 that has shrunk, and is extracted from the vulcanizer 1.

  According to the present invention, in order to change the injection vertical direction of the heating medium M1 and the pressurizing medium M2 to the vulcanization bladder 2, the above-described simple operation is performed using the pressure difference between the heating medium M1 and the pressurizing medium M2 to be injected. It has a simple configuration. Inside the vulcanization bladder 2, the pressure medium M2 having a specific gravity larger than that of the heating medium M1 moves downward from the injected upper position, so that the heating medium M1 and the pressure medium M2 are easily mixed. Along with this, the heating medium M1 having a relatively small specific gravity is unevenly distributed in the upper position of the vulcanizing bladder 2 and the pressure medium M2 having a relatively large specific gravity is unevenly distributed in the lower position of the vulcanizing bladder 2 can be corrected. Therefore, the upper and lower temperature difference of the vulcanization bladder 2 can be effectively reduced. As a result, the variation in the degree of vulcanization of the tire becomes smaller at the top and bottom, leading to an improvement in tire quality.

  Further, in this vulcanizing apparatus 1, it is not necessary to provide separate injection lines 6L for supplying the heating medium M1 and the pressurized medium M2, and only one system is sufficient. This also contributes to the simplification of the vulcanizer 1.

  In this embodiment, as illustrated in FIG. 4, the heating medium M <b> 1 and the pressurizing medium M <b> 2 respectively from the inlets 6 </ b> A and 6 </ b> B are at an angle of 10 ° to 60 ° with respect to the radial direction of the vulcanization bladder 2. It is set to be injected in the intersecting direction. This angle can be set to 0 °, and the heating medium M1 and the pressure medium M2 can be injected radially from the injection ports 6A and 6B in the radial direction of the vulcanization bladder 2 in a plan view, as illustrated in FIG. Thus, when it inject | pours in the direction which cross | intersects the radial direction of the vulcanization bladder 2, the heating medium M1 and the pressurization medium M2 rotate centering on the center post 4a. This swirl facilitates the mixing of the vulcanizing medium M1 and the pressurized medium M2, so that it is more advantageous to effectively reduce the vertical temperature difference of the vulcanizing bladder 2.

  In order to more effectively reduce the upper and lower temperature difference of the vulcanization bladder 2 by mixing the heating medium M1 and the pressure medium M2 evenly, the inlet 6A is inclined by more than 0 ° and not more than 30 ° with respect to the horizontal direction. The angle may be set downward toward the outer peripheral side, and the inlet 6B may be set upward toward the outer peripheral side at an inclination angle A1 of more than 0 ° and not more than 50 ° with respect to the horizontal direction. A plurality of injection ports 6A and 6B may be provided at equal intervals in the circumferential direction.

  When the urging member 10 that urges the valve body 9 downward is provided as in this embodiment, the pressure for opening and closing the two types of inlets 6A and 6B can be changed only by changing the urging force by the urging member 10. Can be adjusted easily.

DESCRIPTION OF SYMBOLS 1 Vulcanization apparatus 2 Vulcanization bladder 3a Upper clamp part 3b Lower clamp part 4 Center mechanism 4a Center post 5a Upper clamp holding part 5b Lower clamp holding part 6A Relatively downward inlet 6B Relatively upward inlet 6L Injection line 7 Discharge port 7L Discharge line 8 Switching mechanism 9 Valve body 9a First valve portion 9b Second valve portion 10 Energizing member 11 (11a, 11b, 11c) Mold G Green tire M1 Heating medium M2 Pressure medium

Claims (4)

A cylindrical vulcanization bladder, a center post that vertically passes through the vulcanization bladder, and an upper clamp holding portion and a lower clamp holding portion that are supported by the center post and hold the upper and lower ends of the vulcanization bladder, respectively. And an injection port disposed inside the vulcanization bladder at a position on the outer peripheral side of the center post, and extends downward from the midway position inside the vulcanization bladder to the outside of the vulcanization bladder. A heating medium supplied through an existing injection line and a pressure medium having a higher pressure and a higher specific gravity than the heating medium are injected into the vulcanization bladder from the injection port connected to the injection line and expanded. In a vulcanizing device for a pneumatic tire that vulcanizes a green tire that is placed horizontally in a tire mold,
As the injection port, two types of injection ports having different injection directions in the vertical direction are provided, and the two types of injection ports are opened and closed by operating the pressure of the heating medium and the pressure medium in the injection line. A switching mechanism is disposed, a relatively upward inlet of the two types of inlets is disposed at a position higher than a relatively downward inlet, and the switching mechanism includes a first valve portion and a first valve. A valve body that is movable in the vertical direction by the pressure of the heating medium and the pressure medium inside the injection line, and has a second valve portion that is disposed above the portion. An urging member for urging the valve body downward is provided, and when the heating medium is supplied through the injection line , a downward urging force by the urging member is applied to the valve body by the pressure of the heating medium . Against By upward movement, when the second by second valve unit to a state of being opened the relatively downward inlet causes the closing of the relatively upward inlet, supplying the pressurizing medium through the inlet line Further, the valve body is moved upward against the downward urging force of the urging member by the pressure of the pressurizing medium, and the relatively downward inlet is closed by the first valve portion, The pneumatic tire vulcanizing apparatus is characterized in that the relatively upward inlet is opened . The relatively downward injection port is set downward toward the outer peripheral side at an inclination angle of more than 0 ° and not more than 30 ° with respect to the horizontal direction, and the relatively upward injection port is set with respect to the horizontal direction. The vulcanizing apparatus for a pneumatic tire according to claim 1 , wherein the vulcanizing apparatus is set upward toward the outer peripheral side at an inclination angle of more than 0 ° and not more than 50 °. The pneumatic tire vulcanizing device according to claim 1 or 2 , wherein a plurality of the relatively downward inlets and the relatively upward inlets are provided at equal intervals in the circumferential direction. The injection direction by the relatively downward inlet and the relatively upward inlet is set to intersect with the radial direction of the vulcanization bladder at an angle of 10 ° to 60 ° in plan view. The vulcanizing device for a pneumatic tire according to any one of claims 1 to 3 .

Images