JP2019072878A - Tire molding device - Google Patents

Abstract

To provide a device for molding a low cover, that suppresses generation of an air reservoir.SOLUTION: A molding device 2 comprises a drum 4 for winding an inner liner member and a side wall member 14 on an outer peripheral surface 4a by rotating the outer peripheral surface 4a in a circumferential direction, a supply device 6 for supplying the side wall member 14 to the drum 4, a holing device 8 for forming through holes 58 in the side wall member 14 conveyed by the supply device 6, and a shaping former for diameter-expanding a first molded body by filling a radial direction inner surface of the first molded body including the inner liner member and the side wall member 14 with applied pressure air.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a tire molding apparatus.

  In the manufacture of a tire, members forming parts of the tire are provided. These members are combined to form a raw cover using a molding apparatus. The low cover is vulcanized to obtain a tire from the low cover.

  JP-A-2000-301626 discloses a holing device used as a member for forming each part of a tire. This holing device forms an air vent through hole in these members. These members are combined to form a low cover. By forming the through holes, it is possible to suppress the occurrence of air accumulation between the members when the members are combined.

  Japanese Patent Laid-Open No. 2001-287513 discloses a method of preforming a raw cover. This publication discloses a first molded body in which an inner liner member and a sidewall member are combined, and a second molded body in which a tread member and the like are combined. The first compact is expanded in diameter by the bladder. The expanded first compact and the second compact are pressure-bonded to form a raw cover.

JP 2000-301626 A JP 2001-287513 A

  As a method of expanding the diameter of the first molded body, when the inner surface of the first molded body is filled with air and expanded in diameter, the inner liner member holds the internal pressure. In this first molded body, a minute gap may exist at the joint of the inner liner member. In this case, when the first compact is filled with air, air intrudes into the interior of the first compact from the joint.

  Generally, after forming the through holes, the members forming the respective parts of the tire are wound and stored in rolls until they are used to form a low cover. In the member stored in this manner, the through holes are closed at a considerable rate at the stage of use for molding. In such a case, the intruding air forms an air pool in the sidewall member. This air pool causes deformation such as partial swelling. The low cover, which has undergone such deformation, must be discarded as a defective product.

  An object of the present invention is to provide an apparatus for forming a low cover in which the occurrence of air accumulation is suppressed.

The molding apparatus according to the present invention is
A drum configured to rotate an outer peripheral surface in a circumferential direction to wind an inner liner member and a sidewall member around the outer peripheral surface;
A supply device for supplying the sidewall member to the drum;
A holing device for forming a through hole in the side wall member transported by the supply device;
A radially inner surface of a first molded body including the inner liner member and the sidewall member is filled with a fluid to expand the diameter of the first molded body.

Preferably, the forming device is
A function of specifying a circumferential position of a joint of the inner liner member wound on the drum;
A function of forming a through hole in a perforated region of the sidewall member at a predetermined distance in the longitudinal direction from the tip of the sidewall member transported by the supply device;
Positioning the perforated area so as to overlap the joint position, and winding the sidewall member on the drum;
Is equipped.

  Preferably, the forming device comprises a controller. The control device has a function of specifying a circumferential position of the joint, a function of forming a through hole in the perforation area by the holing device, and a position of the perforation area so as to overlap the joint position. And the function of winding the side wall member.

  Preferably, the diameter of the hauling needle of the hauling device is 3 mm or less.

The method of preforming a raw cover according to the present invention is
An intermediate forming step in which an intermediate is formed, including an inner liner member wound into a cylindrical form into a drum;
Supplying the side wall member to the drum;
A first forming step of winding the side wall member around the drum, overlapping the intermediate body and the side wall member, and forming a first molded body;
A shaping step of filling the radial inner surface of the first molded body with a fluid to expand the diameter;
Is equipped.
In the supply step, a through hole is formed in the sidewall member.

  Preferably, in the intermediate forming step, the circumferential position of the joint of the inner liner member is specified. In the feeding step, a perforated area of the sidewall member is set in an area overlapping the joint of the intermediate when wound on the drum, and a through hole is formed in the perforated area.

  Preferably, in the first forming step, the circumferential length of the perforated area is 4 mm or more and 15 mm or less.

  In this forming device, through holes are formed in the side wall members transported by the supply device. The sidewall member is excellent in the ability to discharge fluid intruding from the joint of the inner liner member. In this molding device, the occurrence of air accumulation in the sidewall member is suppressed.

FIG. 1 is a perspective view showing a part of a molding apparatus according to an embodiment of the present invention. FIG. 2 is an explanatory view showing another part of the molding apparatus of FIG. FIG. 3 is an explanatory view showing a use state of the molding apparatus of FIG. FIG. 4 is an explanatory view showing a part of a cross section taken along line IV-IV of FIG. FIG. 5 is an explanatory view showing another use state of the molding apparatus of FIG.

  Hereinafter, the present invention will be described in detail based on preferred embodiments with reference to the drawings as appropriate.

  A part of the molding apparatus 2 is shown in FIG. As shown in FIG. 1, the forming device 2 includes a drum 4, a feeding device 6, a holing device 8 and a control device 10. Arrow X in FIG. 1 represents forward and backward direction of the forming device 2, arrow Y represents rightward and left direction of the forming device 2, and arrow Z represents upward direction in the vertical direction. The intermediate body 12 wound around the drum 4 and the sidewall member 14 are shown together with the forming device 2 in FIG.

  The drum 4 has a cylindrical shape. The drum 4 includes an outer circumferential surface 4 a around which the intermediate body 12 and the sidewall member 14 are wound. The axial direction of the drum 4 coincides with the left-right direction of the molding device 2. The drum 4 is rotated in the circumferential direction, and has a function of winding a member forming the intermediate body 12 and the sidewall member 14 around the outer peripheral surface 4 a.

  The supply device 6 includes a conveyer 16, a conveyer 18 and a conveyer 20. The feeding device 6 further includes a cutting device not shown. The transport conveyor 16 and the transport conveyor 18 have a function of transporting the sidewall member 14 toward the drum 4. The transfer conveyor 20 has a function of supplying the sidewall member 14 to the drum 4. The cutting device has a function of forming a sidewall member 14 by cutting a long strip member (not shown) into a predetermined length.

  The feeding device 6 has a function of conveying the belt-like member toward the drum 4, a function of cutting the belt-like member to form the sidewall member 14, and a function of conveying the sidewall member 14 toward the drum 4. Is equipped. In the supply device 6, the transport conveyors 16, 18 and 20 are exemplified, but the supply device 6 may transport the belt-like member and the sidewall member 14. Other conveying devices such as a roller conveyor may be used as the feeding device 6.

  The holing device 8 includes a drive unit 22, a plurality of holing needles 24, a guide plate 26, and a pedestal 28. The holing device 8 is disposed between the conveyer 16 and the conveyer 18. The drive unit 22 has a function of moving the holing needle 24 in the vertical direction. The guide plate 26 and the pedestal 28 have a function of fixing the sidewall member 14 with the sidewall member 14 interposed therebetween as the holing needle 24 descends. The holing device 8 has a function of perforating the side wall member 14 by a holing needle 24. The holing device 8 can be positioned by changing its position in the feed direction of the sidewall member 14 (in the front-rear direction in FIG. 1).

  As shown in FIG. 2, the molding device 2 further includes a shaping former 32, a tread molding device 34 and a tread conveyance device 36.

  The shaping former 32 includes a former main body 38 and a pair of bead receiving portions 40. The former main body 38 is disposed with the left and right direction in FIG. 2 as its axial direction. The pair of bead receiving portions 40 is mounted on the outer periphery of the former main body 38. The pair of bead receiving portions 40 is movable in the axial direction of the former body 38. Thereby, the axial direction space | interval of a pair of bead receiving part 40 is made changeable. Although not shown, the former body 38 is provided with an outlet for pressurized air as a fluid.

  The tread forming device 34 includes a tread drum 42. The tread drum 42 has a cylindrical shape. The tread drum 42 is rotatable in the circumferential direction. The tread transport device 36 includes a holder 46. The tread transport device 36 is movable between the tread drum 42 and the shaping former 32.

  A cross section of the first formed body 50 wound around the drum 4 is shown in FIG. FIG. 3 shows a cross section perpendicular to the circumferential direction. The first molded body 50 is formed by winding the sidewall member 14 around the intermediate body 12. The intermediate body 12 includes an inner liner member 52, a carcass ply member 54 and a pair of bead members 56. A carcass ply member 54 is wound radially outward of the inner liner member 52. One axial end 54 a of the carcass ply member 54 is folded around one bead member 56. The other axial end 54 b of the carcass ply member 54 is folded around the other bead member 56. A pair of sidewall members 14 are wound radially outward of the carcass ply member 54.

  The inner liner member 52 is a member that forms the inner liner of the tire. The inner liner has a function of holding the internal pressure of the tire. The carcass ply member 54 is a member that forms the carcass of the tire. The carcass consists of cords and topping rubber. The bead member 56 is a member that forms a bead of the tire. The carcass is bridged between a pair of beads to form a tire skeleton together with the beads. The sidewall member 14 is wound around the outer peripheral surface of the intermediate body 12. The sidewall member 14 is a member that forms a sidewall of the tire. The sidewalls form the axial outer surface of the tire.

  In FIG. 4, for convenience of explanation, one end 52 a of the circumferential direction of the inner liner member 52 and the other end 52 b are separated, but the end 52 a and the end 52 b are connected. The inner liner member 52 is cylindrical. The symbol Pa represents a joint of the cylindrically wound inner liner member 52. The joint Pa is specified as a circumferential end located radially outward on the outer peripheral surface of the inner liner member 52. In the inner liner member 52, the end 52b is superimposed on the outside of the end 52a, and the end on the end 52b side is a joint Pa. The joint Pa extends in the axial direction on the outer peripheral surface of the inner liner 52. An alternate long and short dash line La represents an imaginary straight line extending radially through the joint Pa.

  A plurality of through holes 58 are formed in the sidewall member 14. The double arrow Ah in FIG. 4 represents the circumferential length of the perforated area in which the through hole 58 is formed. The length Ah is measured as a circumferential distance on the outer peripheral surface of the wound side wall member 14. The length Ah is, on the outer peripheral surface of the sidewall member 14, from one circumferential end of the through hole 58 located on the one circumferential side to the other circumferential end of the through hole 58 located on the other circumferential side. It is measured as a distance. The length Ah is set in a region where the straight lines La intersect. In other words, the perforated area is set at a position including the joint Pa in the circumferential direction. This perforated area is superimposed at the position of the joint Pa.

  The inner liner member 52 of the intermediate body 12 is not formed with a through hole penetrating from the inner peripheral surface to the outer peripheral surface. Although not shown, the carcass ply member 54 is formed with a plurality of through holes penetrating from the inner peripheral surface to the outer peripheral surface. In the sidewall member 14, a through hole 58 is formed in the perforation region in the circumferential direction. In the sidewall member 14, the through hole 58 is not formed in the area other than the perforated area. However, other through holes formed in the long strip-like member may remain in the area other than the perforated area before the supply process.

  FIG. 5 shows how the first molded body 50 is crimped to the second molded body 60. The second molded body 60 includes a tread member 62, a belt member 64 and a band member 66. In the second molded body 60, the band member 66 is wound around the outer periphery of the belt member 64, and the tread member 62 is wound around the outer periphery of the band member 66. The second molded body 60 has a cylindrical shape.

  The tread member 62 is a member that forms the tread of the tire. The tread forms the radially outer surface of the tire and forms a tread surface that contacts the road surface. The belt member 64 is a member that forms the belt of the tire, and the band member 66 is a member that forms the band of the tire. The belts and bands are located between the tread and the carcass to reinforce the carcass.

  In FIG. 5, the first molded body 50 is attached to the shaping former 32 (see FIG. 2). The end of the first molded body 50 is supported by the bead receiving portion 40. The first formed body 50 is filled with pressurized air and diameter-expanded. The inner peripheral surface of the first molded body 50 is directly filled with pressurized air. The first molded body 50 is expanded in a toroidal shape. The second molded body 60 is pressure-bonded to the outer peripheral surface of the first molded body 50 whose diameter is increased.

  Here, a method of manufacturing a pneumatic tire according to the present invention will be described. This manufacturing method comprises a preforming step as the preforming method of the present invention and a vulcanization step. In the preforming step, a raw cover is formed. In the vulcanization step, the raw cover is vulcanized to obtain a tire from the raw cover.

  This preforming step is described with reference to FIGS. 1 to 5. The preliminary forming step includes an intermediate forming step, a supplying step, a first forming step, a first formed body transferring step, a second forming step, a second formed body transferring step, a shaping step and a formed body pressing step.

  In the intermediate forming process, the inner liner member 52 is wound around the drum 4 shown in FIG. One end 52 a of the inner liner member 52 in the circumferential direction and the other end 52 b are crimped. The inner liner member 52 is cylindrical. In the forming device 2, the circumferential position at which the inner liner member 52 starts to be wound is fixed on the outer peripheral surface 4 a of the drum 4. For example, by adjusting the feeding of the supply device for the inner liner member 52 (not shown) and the rotation of the drum 4, the circumferential position at which the inner liner member 52 starts to be wound is made constant. Thereby, the circumferential direction position of joint Pa of inner liner member 52 is specified.

  In the intermediate forming process, a carcass ply member 54 is prepared. Although not shown here, the carcass ply member 54 is formed with a plurality of through holes penetrating in the thickness direction. A carcass ply member 54 is wound on the outside of the cylindrical inner liner member 52. The circumferential ends of the carcass ply member 54 are overlapped and crimped. The carcass ply member 54 is tubular.

  A pair of bead members 56 are disposed radially outward of the carcass ply member 54. The end 54a of the carcass ply member 54 is folded around one bead member 56, and the end 54b of the carcass ply member 54 is folded around the other bead member 56. Thus, an intermediate 12 is formed.

  In the supply step, a strip-shaped member forming the sidewall member 14 is prepared. Although not shown, this strip is prepared as a wound body wound on a roll. From the wound body, the feeding device 6 conveys the belt-like member toward the drum 4. The strip-like member is cut into a predetermined length by a cutting device (not shown). The side wall member 14 is formed by this cutting.

  The holing device 8 pierces a perforated area of the sidewall member 14 at a predetermined distance from the tip of the sidewall member 14 in the longitudinal direction. A plurality of through holes 58 are formed by the perforations. For example, when the cut sidewall member 14 is conveyed toward the drum 4, the supply device 6 conveys the sheet by a predetermined distance and stops. In this stop position, the perforated area of the sidewall member 14 is located in the holing device 8. As a result, the through holes 58 are formed in the perforated area at a predetermined distance from the tip of the sidewall member 14.

  In the supply step, the through holes 58 may be formed in the band-shaped member before being cut into the sidewall member 14. When the strip-like member is cut to form the sidewall member 14, the through hole 58 may be formed in a perforated area at a predetermined distance from the tip of the sidewall member 14.

  In the first forming step, the sidewall member 14 is wound around the outer peripheral surface of the intermediate body 12. In the outer peripheral surface 4 a of the drum 4, a circumferential position at which the sidewall member 14 is to be wound is determined. In this forming device 2, by adjusting the feed of the supply device 6 and the rotation of the drum 4, the circumferential position at which the sidewall member 14 starts to be wound is made constant. Thereby, the perforation region is positioned at a position covering the circumferential position of the joint Pa of the inner liner member 52, and the sidewall member 14 is wound.

  In the first molded body conveying step, a conveying device (not shown) conveys the first molded body 50 from the drum 4 to the shaping former 32. The first molded body 50 is attached to the shaping former 32 shown in FIG. The pair of bead receiving portions 40 of the shaping former 32 support the pair of axial end portions of the first molded body 50.

  In the second molding step, the belt member 64 is wound around the tread drum 42 shown in FIG. A band member 66 is wound around the outside of the belt member 64. The tread member 62 is wound around the outside of the band member 66. Thus, the second molded body 60 is formed.

  In the second molded body conveying step, the tread conveying device 36 moves toward the tread molding device 34. The tread transport device 36 positions the holder 46 radially outward of the tread drum 42. The holder 46 holds the second molded body 60. The tread transport device 36 moves toward the shaping former 32. The tread transport device 36 holds the second compact 60 radially outward of the former body 38.

  In the shaping step, the inner peripheral surface of the first molded body 50 is filled with pressurized air. The first molded body 50 is radially expanded. The pair of bead receiving portions 40 move inward in the axial direction in accordance with the diameter expansion. Thus, the first compact 50 is expanded in a toroidal shape.

  In the molded body pressure bonding step, the expanded first molded body 50 is pressure bonded to the second molded body 60 held by the tread conveyance device 36. Furthermore, the second molded body 60 is crimped to the first molded body 50 by a stitcher (not shown). The first molded body 50 and the second molded body 60 are pressure-bonded to form a raw cover.

  The forming device 2 pierces the side wall member 14 transported by the feeding device 6. In the forming device 2, the sidewall member 14 is perforated on the way to the drum 4 and wound around the drum 4. The sidewall member 14 is immediately wound around the drum 4 without being wound around the storage roller after the through holes 58 are formed. Thereby, the first molded body 50 is formed without blocking the through hole 58. The sidewall member 14 is excellent in the air discharging property. Even when the first molded body 50 is filled with pressurized air on its inner surface, generation of air accumulation can be suppressed.

  The forming device 2 specifies the circumferential position of the joint Pa of the inner liner member 52 wound around the drum 4. The forming apparatus 2 forms a through hole 58 in a perforated area at a predetermined distance from the tip of the side wall member 14 to be transported. The forming device 2 positions the perforated area at a position overlapping the position of the joint Pa and causes the drum 4 to wind the sidewall member 14. In this forming device 2, the perforated area is positioned so as to overlap the position of the joint Pa of the inner liner member 52. Thus, the air that has entered the inside from the joint Pa of the inner liner member 52 is discharged through the through holes 58. Thereby, the occurrence of air accumulation inside the first molded body 50 is suppressed.

  In the molding device 2, the hole device 8 can change its position in the front-rear direction. By changing the position of the holing device 8, the distance from the tip of the sidewall member 14 to the perforation area can be easily adjusted. By this, this holing device 8 can form a perforated area at an appropriate position in the low cover of different outer diameter. The forming device 2 provided with the holing device 8 can form a perforated area at appropriate positions of various tires. The molding apparatus 2 is excellent in versatility.

  Here, by defining the timing of the conveyance of the feeding device 6, the operation of the holing device 8, and the rotation of the drum 4, the joint Pa and the perforation area are made to overlap in the circumferential direction of the drum 4. It is not limited. For example, the control device 10 has a function of identifying the circumferential position of the joint Pa, a function of causing the holed area to be perforated by the holing device 8, and a drum 4 with the perforation area positioned at a position overlapping the joint Pa in the circumferential direction And the sidewall member 14 may be wound.

  Specifically, the control device 10 winds the inner liner member 52 around the drum 4 so that the tip of the inner liner member 52 is positioned at a predetermined circumferential position. Thus, the control device 10 specifies the circumferential position of the joint Pa of the inner liner member 52. The control device 10 sets in advance the circumferential direction position of the tip of the sidewall member 14 when the sidewall member 14 is wound around the drum 4. From the positional relationship between the circumferential position of the tip and the circumferential position of the joint Pa of the inner liner member 52, the control device 10 sets the perforation region of the sidewall member 14 on the radially outer side of the joint Pa. The controller 10 drills in this drilling area by means of the holing device 8. Thereafter, the control device 10 winds the sidewall member 14 around the drum 4 such that the tip end of the sidewall member 14 is positioned at a predetermined circumferential position. In this manner, the sidewall member 14 may be wound with the perforation area positioned so as to overlap the joint Pa.

  The forming device 2 pierces the sidewall member 14 conveyed to the supply device 6. The sidewall member 14 is wound around the drum 4 immediately after the through hole 58 is formed. In the sidewall member 14, the through hole 58 is difficult to close. For this reason, air is sufficiently exhausted by the relatively small through holes 58. In addition, since the sidewall forms the axial outer surface of the tire, the appearance is also important. From these viewpoints, the diameter of the holing needle 24 of the holing device 8 is preferably 3 mm or less. The diameter of the holed needle 24 is measured as the diameter of the portion forming the through hole 58.

  The first molded body 50 having a short circumferential length Ah of the perforated area contributes to the improvement of the appearance of the tire. From this viewpoint, the circumferential length Ah is preferably 15 mm or less, more preferably 13 mm or less. On the other hand, the first molded body 50 having a long circumferential length Ah of the perforated area is excellent in the air discharging property. From this viewpoint, the circumferential length Ah is preferably 4 mm or more, and more preferably 6 mm or more.

  Hereinafter, the effects of the present invention will be clarified by examples, but the present invention should not be interpreted in a limited manner based on the description of the examples.

[Example]
A tire was manufactured using the molding apparatus shown in FIGS. 1 and 2. The tire size was 155 / 65R14. The internal pressure in the shaping step was 0.18 MPa.

[Comparative example]
A tire was manufactured in the same manner as the example except that the holling device was not operated.

[Punk rate evaluation]
In the manufacturing method of the example and the comparative example, the occurrence rate of the puncture of the low cover in the shaping step was evaluated. The blowout of the low cover refers to a phenomenon in which an air reservoir is formed inside the sidewall member and the sidewall member is partially swollen. The evaluation results are shown in Table 1.

  As shown in Table 1, in the manufacturing method of the example, the evaluation is higher than the manufacturing method of the comparative example. The superiority of the present invention is clear from the evaluation results.

  The method described above can be widely applied to a raw cover preforming method in which the inner surface of the first molded body is filled with a fluid and shaped in the shaping step.

2 ... molding device 4 ... drum 6 ... supply device 8 ... hauling device 10 ... control device 12 ... intermediate 14 ... sidewall member 24 ... hauling needle 32 · · · ·· Shaping former 50 · · · First molded body 52 · · · Inner liner member 52a · · · One end 52b · · · the other end 54 · · · carcass ply member 58 · · · through hole

Claims (7)

A drum configured to rotate an outer peripheral surface in a circumferential direction to wind an inner liner member and a sidewall member around the outer peripheral surface;
A supply device for supplying the sidewall member to the drum;
A holing device for forming a through hole in the side wall member transported by the supply device;
A molding apparatus comprising: a shaping former for filling a radial inner surface of a first molded body including the inner liner member and the sidewall member with a fluid to expand the diameter of the first molded body. A function of specifying a circumferential position of a joint of the inner liner member wound on the drum;
A function of forming a through hole in a perforated region of the sidewall member at a predetermined distance in the longitudinal direction from the tip of the sidewall member transported by the supply device;
Positioning the perforated area so as to overlap the joint position, and winding the sidewall member on the drum;
The forming apparatus according to claim 1, comprising:   A control device is provided, and the control device has a function of specifying a circumferential position of the joint, a function of forming a through hole in the perforation area by the holing device, and the perforation so as to overlap the joint position. The forming apparatus according to claim 2, further comprising: a function of positioning an area and winding the sidewall member on the drum.   The molding apparatus according to any one of claims 1 to 3, wherein the diameter of the holling needle of the holing device is 3 mm or less. An intermediate forming step in which an intermediate is formed, including an inner liner member wound into a cylindrical form into a drum;
Supplying the side wall member to the drum;
A first forming step of winding the side wall member around the drum, overlapping the intermediate body and the side wall member, and forming a first molded body;
A shaping step of filling the radial inner surface of the first molded body with a fluid to expand the diameter;
Equipped with
The preforming method of the raw cover which forms a through-hole in the said sidewall member in the said supply process. Specifying the circumferential position of the joint of the inner liner member in the intermediate forming step;
The method according to claim 5, wherein in the supplying step, a perforated area of the sidewall member is set in an area overlapping the joint of the intermediate when wound on the drum, and a through hole is formed in the perforated area. Preforming method.   7. The preforming method according to claim 6, wherein the circumferential length of the perforated area in the first forming step is 4 mm or more and 15 mm or less.

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