JP2012035562A - Device for molding unvulcanized tire and method of molding the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device for a molding unvulcanized tire and a method of manufacturing the same increasing/decreasing the diameter of a molding drum according to the size of a belt tread to be molded.SOLUTION: The device for molding the unvulcanized tire includes the molding drum, a shaping drum 14, an outer shaft 22 of the molding drum, a hollow shaft 24 disposed in the outer shaft 22, and a center shaft 26 of the shaping drum 14 disposed in the hollow shaft which are coaxially arranged, a drive means for rotationally driving each shaft, and a segment drive mechanism for radially moving the segment. The segment drive mechanism moves the segment in the radius direction of the molding drum by a slide nut screwing with the rotation of the outer shaft 22 relative to the hollow shaft 24, and a slide projection 25 integrated with the slide nut to increase/decrease the diameter of the molding drum according to the size of the belt tread.

Description

  The present invention relates to an unvulcanized tire molding apparatus and molding method.

2. Description of the Related Art Conventionally, there is known a method of manufacturing an unvulcanized (green) tire by molding a carcass band, a belt tread formed thereon and a belt tread made of a tread in separate steps, and combining them. .
In this molding method, an expandable / contractable belt molding drum composed of a plurality of segments divided into a plurality in the circumferential direction is used. In this belt molding drum, when the belt tread is molded, the plurality of segments are maintained in a diameter-expanded state, and tire constituent members are attached to the drum peripheral surface and laminated to form a belt tread.

In this conventional belt tread molding apparatus, before the belt tread (BT) material that has been conveyed is wound around the molding drum, the diameter of the molding drum is expanded and the expanded diameter is maintained, and the belt is rotated while the molding drum is rotated. Wrap the tread material around the molding drum.
When the winding of the belt tread material around the molding drum is completed, the molding drum is reduced, the belt tread whose diameter is maintained by rigidity is removed from the molding drum, and the belt tread is conveyed onto the shaping drum on which the green case is arranged.
In this state, the green case is inflated with a shaping drum and attached to the inner surface of the belt tread to produce a green tire.

FIG. 7 shows an example of a conventional molding drum that is not described in the patent literature. FIG. 7A shows a state in which the molding drum has a reduced diameter, FIG. 7B shows a state in which the molding drum has been expanded, and FIG. 7C shows a state in which the molding drum has been reduced in diameter after a diameter expansion. Is shown in a side sectional view.
In this molding drum, as a mechanism for expanding and contracting the segment 135, as shown in the figure, a cylinder chamber 122 is provided around the center shaft 120, and the axis of the center shaft 120 is supplied by air supplied into the cylinder chamber 122. A cam follower 124 integrally provided on the inner periphery of each segment 135 is pushed outward in the radial direction by a cam surface (inclined guide or tapered cone) 121 moving (sliding) in the direction. That is, the cam follower 124 expands radially outward while expanding it against the restraining force of the rubber band 140 disposed on each segment 135. Maintaining the air pressure in this expanded state keeps the drum diameter constant, rotates the molding drum in that state, winds the belt tread around the surface, and discharges the air when the winding is completed, so that the drum is compressed. The structure which diameters is employ | adopted (prior art 1).

  On the other hand, in the tire molding drum, a screw shaft that is rotatable relative to the outer shaft is disposed in a cylindrical outer shaft that constitutes the central axis of the molding drum, and a moving member that is screwed into the screw shaft and each of the moving members. An expansion / contraction mechanism is also known in which each segment is expanded and contracted by connecting the segments via a link member and moving the moving member in the axial direction by rotation of the screw shaft (Patent Documents 1 and 2). 3).

However, in the molding drum according to the prior art 1, since the expansion / contraction mechanism has only one pattern of expansion and contraction, the size of the belt tread that molds a member (tool) that defines the expansion amount of the expansion / contraction mechanism. It needs to be changed accordingly. That is, every time the size of the belt tread changes, the jig must be changed, and there is a problem that work efficiency is not good.
Moreover, in the molding drum described in the said patent documents 1-3, in order to expand and contract a drum using a screw transmission mechanism, a part of mechanism is changed according to belt tread size like the prior art 1. FIG. No need for trouble.
However, in this molding drum, the shaping drum for creating the green case and the molding drum for molding the belt tread attached to the green case are arranged at different locations, so that both space and cost are required. There is room for improvement.

JP 2009-137041 A WO2007-116502 JP 54-63184 A

  The present invention has been made in view of the problems of the conventional molding apparatus, and its purpose is to form a belt tread of any size, and to form an unvulcanized tire that is compact and reduced in cost. It is to realize an apparatus and a molding method of an unvulcanized tire.

(1) An unvulcanized tire molding apparatus according to the present invention includes a molding drum provided with a plurality of segments movable in the radial direction, and a first tire constituent member molded by the molding drum. A shaping drum for affixing to the tire constituent member, an outer shaft of the molding drum arranged concentrically, a hollow shaft arranged in the outer shaft, and a shaping drum arranged in the hollow shaft And a segment driving mechanism for moving the segment in the radial direction. The segment driving mechanism is a screw provided on the outer periphery of the hollow shaft. A slider screwed into the groove and connected through a groove extending in the axial direction of the outer shaft; and an expansion / contraction mechanism connected to the slider, the expansion / contraction mechanism rotating relative to the hollow shaft and the outer shaft More, by moving the segments radially through said slider, characterized in that it scaled to fit the size of the tread members to mold the molding drum.
(2) An unvulcanized tire molding apparatus according to the present invention is the unvulcanized tire molding apparatus described in (1) above, wherein the molding apparatus is configured to transport the molded first tire constituent member to a shaping drum. It is characterized by having.
(3) The unvulcanized tire molding apparatus according to the present invention is the unvulcanized tire molding apparatus according to (1) or (2), wherein the driving means for rotationally driving each shaft is the outer shaft. A first driving means for driving the second shaft and a second driving means for driving the hollow shaft, or a common driving means for driving the outer shaft and the hollow shaft. It is connected to either one of the two driving means or the common driving means via a clutch means.
(4) The method for molding an unvulcanized tire of the present invention includes a step of conveying a first tire constituent member to a molding drum, and rotating the molding drum to attach the first tire constituent member to the molding drum. A molding step of molding, a step of conveying the molded first tire component to a shaping drum, and a second tire component different from the molded first tire component on the shaping drum. A non-vulcanized tire molding method comprising: an outer shaft of the molding drum disposed concentrically, a hollow shaft disposed in the outer shaft, and a hollow shaft disposed in the hollow shaft. The slider is connected through a groove extending in the axial direction of the outer shaft by rotating the outer shaft and the hollow shaft relative to each other and screwing into a screw groove provided on the outer periphery of the hollow shaft. The And a step of expanding and contracting the segment driving mechanism in accordance with the size of a tread member for molding the molding drum, by expanding and contracting a segment driving mechanism by sliding the slider and moving the segment in a radial direction. It is characterized by having.
(5) The method for molding an unvulcanized tire according to the present invention is the method for molding an unvulcanized tire described in (4) above, wherein a conveying step of conveying the molded first tire constituent member to a shaping drum is performed. It is characterized by having.
(6) The unvulcanized tire molding apparatus according to the present invention is the unvulcanized tire molding apparatus according to any one of (1) to (3), wherein the first tire constituent member is a tread member. The second tire constituent member is a green case.
(7) The method for molding an unvulcanized tire according to the present invention is the method for molding an unvulcanized tire described in (4) or (5), wherein the first tire constituent member is a tread member, The second tire constituent member is a green case.

  ADVANTAGE OF THE INVENTION According to this invention, the molding apparatus or the molding method of the unvulcanized tire which can respond to shaping | molding of belt treads of arbitrary sizes, and is compact and reduced in cost can be obtained.

It is a top view which shows roughly the shaping | molding apparatus of an unvulcanized tire. It is a perspective view of the shaping | molding apparatus of an unvulcanized tire. FIG. 3A is a perspective view schematically showing a driving shaft of a molding drum and a shaping drum, in which FIG. 3A shows a state before the sliding protrusion is expanded, and FIG. 3B shows an operation direction when the sliding protrusion is expanded. FIG. 3C shows the operation direction when the diameter is reduced. FIG. 4A is a cross-sectional view of the outer shaft and the hollow shaft, FIG. 4B is a perspective view thereof, and FIG. 4C is an outer fit to the outer shaft, the hollow shaft, and the outer shaft. FIG. 4D is a perspective view of the slider. It is the schematic which shows the structure of a drive device concretely, and has shown the drive means of an outer shaft and a hollow shaft schematically. It is sectional drawing which shows the expansion / contraction structure of a shaping | molding drum roughly, an upper half shows the diameter expansion state of a shaping | molding drum, and a lower half shows the diameter reduction state of a shaping | molding drum. An example of the conventional molding drum is shown. FIG. 7A shows a state in which the molding drum has a reduced diameter, FIG. 7B shows a state in which the molding drum has been expanded, and FIG. 7C shows a state in which the molding drum has been reduced in diameter after a diameter expansion. Is shown in a side sectional view.

An unvulcanized tire molding apparatus according to an embodiment of the present invention will be described with reference to the accompanying drawings.
FIG. 1 is a plan view schematically showing an unvulcanized tire molding apparatus according to an embodiment, and FIG. 2 is a perspective view thereof.
As shown in FIGS. 1 and 2, the unvulcanized tire molding apparatus 10 rotationally drives a molding drum 12 for molding a belt tread, a shaping drum 14, an O-ring 16, a molding drum 12 and a shaping drum 14. And a driving device 18 for the purpose. Here, the shaping drum 14 is formed by winding and laminating a first tire constituent member, for example, a belt tread, molded by the molding drum 12, by winding a second tire constituent member, for example, an inner liner, a rubber chafer, and a carcass ply. It is a drum that expands and inflates the green case in order to stick to the green case, and the O-ring 16 is movable in the axial direction of the drive shaft 20 of the unvulcanized tire molding apparatus 10 by an arbitrary drive mechanism. The belt tread molded with the molding drum 12 is transported to the shoeping drum 14 or the green tire molded with the shaping drum 14 is transported to a predetermined position.

3 is a perspective view schematically showing the drive shaft 20 and the shaping drum 14. FIG. 3A shows a state before the sliding protrusion 25 is expanded, and FIG. 3B shows an enlarged diameter of the sliding protrusion 25. FIG. FIG. 3C shows the operation direction when the diameter is reduced.
As shown in FIG. 3A, the drive shaft 20 of the unvulcanized tire molding apparatus 10 includes a tubular outer shaft 22 that serves as a rotating shaft of the molding drum 12, a hollow shaft 24 disposed in the outer shaft 22, and a hollow shaft. The center shaft 26 is a rotating shaft of the shaping drum 14 disposed in the shaft 24. A pair of screw grooves (not shown) opposite to each other in the axial direction are provided on the outer peripheral surface of the hollow shaft 24, and a slide nut 21 (FIG. 4) is screwed into each screw groove. On the outer peripheral surface of the slide nut 21, for example, two rectangular sliding protrusions 25 are provided at symmetrical positions with respect to the center thereof, and the sliding protrusion 25 has a moving range of the sliding protrusion 25. And projecting outward through a slit 23 (long groove) provided so as to extend in the axial direction of the outer shaft 22.
3B shows that the sliding protrusions 25 are moved closer to each other to increase the diameter of the molding drum 12, while FIG. 3C shows that the sliding protrusions 25 are moved in a direction away from each other. 12 indicates that the diameter is reduced.

4A and 4B are diagrams for explaining the relationship between the outer shaft 22 and the hollow shaft 24. FIG. 4A is a cross-sectional view of the outer shaft 22 and the hollow shaft 24, FIG. 4B is a perspective view thereof, and FIG. FIG. 4D is a perspective view of the slider 28 fitted on the hollow shaft 24 and the outer shaft 22.
As shown in FIG. 4A, the slide nut 21 is screwed into the thread groove provided on the outer peripheral surface of the hollow shaft 24. The slide nut 21 is integrally provided with sliding protrusions 25 at symmetrical positions with respect to the center thereof as shown in the figure. It protrudes to the outside through a pair of slits 23 provided on the shaft 22.

4C and 4D show a state where an annular slider 28 is externally fitted on the slit 23 of the outer shaft 22 shown in FIGS. 4A and 4B. As is apparent from FIG. 4C, the sliding protrusion 25 protrudes outward from the slit 23 and further passes through an opening 28a provided in the slider 28 corresponding to the sliding protrusion 25, in the illustrated example. Furthermore, it protrudes to the outside.
As a result, when relative rotation occurs between the outer shaft 22 and the hollow shaft 24, the slide nut 21 moves along the outer shaft 22 and the slider 28 moves together as described later.

FIG. 5 is a schematic diagram specifically showing the configuration of the driving device 18, and here, driving means for the outer shaft 22 and the hollow shaft 24 are schematically shown.
For example, sprockets 22a and 24a are integrally attached to the end portions of the outer shaft 22 and the hollow shaft 24, and between the sprockets 22a and 24a and the sprockets M1a and M1b of the motors M1 and M2 that drive the sprockets 22a and 24a. Are spanned by chains 40 and 42, respectively.
FIG. 5A shows a state where, for example, only the motor M1 is driven to rotate only the hollow shaft 24, and FIG. 5B schematically shows the result. That is, in FIGS. 4C and 4D, the slide nut 21, the sliding protrusion 25, and the slider 28 that are screwed into the thread groove provided on the outer periphery of the hollow shaft 24 slide, and as a result, the link mechanism 30 (not shown) FIG. 6) shows a state where the diameter of the molding drum 12 is expanded.
In a state where the diameter of the molding drum 12 is expanded, the motor M2 is operated so that the relative rotation between the outer shaft 22 and the hollow shaft 24 is eliminated, that is, the hollow shaft 24 and the outer shaft 22 are rotated at the same angular velocity. FIG. 5B shows that the molding drum 12 rotates while maintaining the enlarged state.
FIG. 5C shows that only the outer shaft 22 is rotated by the motor M2. Here, the rotation of the outer shaft 22 shows a state where the molding drum 12 is reduced in diameter via a link mechanism 30 (FIG. 6) (not shown).
The transmission mechanism is not limited to this, and may be a timing belt or a timing pulley, for example. Further, the motors M1 and M2 may be replaced with a common motor with a reduction gear, and the center shaft 26 that is a drive shaft of the shaping drum 14 is driven by one of the motors using a clutch mechanism (not shown). The Such a configuration can reduce the space for the driving means and hence the driving device 18, can simplify the configuration, and is advantageous from the viewpoint of cost.

FIG. 6 is a cross-sectional view schematically showing the expansion / contraction structure of the molding drum described above. The upper half shows the expanded diameter state of the molding drum 12, and the lower half shows the reduced diameter state of the molding drum.
An expansion / contraction mechanism, for example, a plurality of link mechanisms 30 are attached to the outer peripheral surface of the slider 28 at equal intervals in the circumferential direction. The link mechanism 30 has a first link 32 having one end pivotably connected to the lower surface of the segment 35 and the other end pivotally connected to the slider 28, and one end at an intermediate position of the first link 32. The second link 34 is connected to the outer shaft 22 so as to be rotatable and slidable.
A plurality of link mechanisms 30 are attached to the outer peripheral surface of the slider 28 in a pair of left and right as illustrated. Here, a mechanism for driving the segment including the slide nut 21, the sliding protrusion 25, the slider 28, and the link mechanism 30 is collectively referred to as a segment drive mechanism.
Although not shown, a rubber belt is disposed on the segment 35 as in the conventional case.

  In the above configuration, when the motors M1 and M2 are rotated or one of them is rotated to give a difference in the rotational speed between the outer shaft 22 and the hollow shaft 24, that is, when they are rotated relative to each other, A force perpendicular to the axial direction acts between the moving projection 25 and the groove wall of the slit 23 of the outer shaft 22. As a result, the slide nut 21 integral with the sliding protrusion 25 rotates around the axis of the hollow shaft 24 and is screwed, so that the slide nut 21, and thus the sliding protrusion 25 and the slider 28 are connected to the outer shaft 22. Move in the axial direction. The movement of the slider 28 causes the link mechanism 30 to undulate and expand the segments in the radial direction, and as the segments 35 expand and contract, the molding drum composed of the rubber belt on each segment 35 expands and contracts.

In the present embodiment, the outer shaft 22 and the hollow shaft 24 are described as being driven by different motors M1 and M2. However, as described above, these use a common motor with a reduction gear (differential reduction gear). By doing so, it can be driven by one motor.
Further, the middle shaft 26 which is a shaft for rotating the shaping drum 14 can share any of the motors by switching the clutch even when the motor M1 or M2 or one motor is used.

Next, the operation of the unvulcanized tire molding apparatus of the present invention will be described.
When a belt tread material (not shown) is conveyed to the molding drum 12, the diameter thereof is changed in accordance with the size of the belt tread for molding the molding drum 12. The diameter is changed by relatively rotating the outer shaft 22 and the hollow shaft 24 as described above. For example, the hollow shaft 24 or the outer shaft 22 is rotated a predetermined number of times in a predetermined direction according to the size of the belt tread to be molded. At this time, either the hollow shaft 24 or the outer shaft 22 may be rotated. However, by stopping the rotation of the outer shaft 22, energy consumption of the outer shaft 22 is reduced, and the diameter is increased or decreased from the appearance. Therefore, it is preferable to rotate the hollow shaft 24.

As described above, when a difference in rotation is made between the rotation of the hollow shaft 24 and the outer shaft 22, the pair of slide nuts 21 screwed into the hollow shaft 24 thereby approach each other by a predetermined distance according to the difference in rotation. Move in the direction. As a result, the link mechanism 30 operates, the first link 32 rises outward in the radial direction, the segment 35 is pushed up in the same direction, and an arbitrary value corresponding to the size (diameter) of the belt tread for molding the molding drum 12 is obtained. A desired diameter can be obtained.
Here, when the molding drum 12 has a predetermined diameter, the rotational angular velocities of the hollow shaft 24 and the outer shaft 22 are made to coincide with each other so that the rotational angular velocity difference between the two becomes zero and the diameter is maintained.
In this state, the belt tread material is wound around the molding drum 12, and when the belt tread is molded, the rotation of the motors M1, M2 or the motor with a reduction gear is stopped.
Thereafter, when the member is carried out from the drum by the O-ring 16, a relative rotation is given between the outer shaft 22 and the hollow shaft 24 with a rotation difference opposite to that described above to reduce the molding drum diameter.

In this embodiment, next, the O-ring 16 is moved to the molding drum 12 by an arbitrary drive mechanism, and the belt tread on the molding drum 12 is accommodated in the inner peripheral surface of the O-ring 16. Subsequently, the O-ring 16 is moved onto a green case (not shown) waiting on the shaping drum 14. In this state, the shaping drum 14 is expanded in diameter, and a belt tread is attached to the green case to form a green tire. After forming the green tire, the shaping drum 14 is reduced in diameter and the O-ring 16 is driven to carry the green tire to a predetermined position.
According to the present embodiment, the center shaft 26 serving as the rotating shaft of the shaping drum 14 is accommodated in the outer shaft 22 and the hollow shaft 24 by switching a clutch mechanism (not shown), and the motors M1 to M2 or the speed reducer. It is a motor with a machine, that is, it is driven to rotate by a common motor.
Therefore, the unvulcanized tire molding apparatus according to the present embodiment can expand the molding drum to an arbitrary diameter, and can be reduced in size and cost as compared with the conventional tire molding apparatus.

  DESCRIPTION OF SYMBOLS 10 ... Molding device of unvulcanized tire, 12 ... Molding drum, 14 ... Shaping drum, 16 ... O-ring, 20 ... Drive shaft, 21 ... Slide nut, 22 ...・ Outer shaft, 22a ... sprocket, 23 ... slit, 24 ... hollow shaft, 24a ... sprocket, 25 ... sliding projection, 28 ... slider, 30 ... link mechanism 32 ... 1st link, 34 ... 2nd link, M1, M2 ... Motor.

Claims (7)

A forming drum having a plurality of segments movable in the radial direction, a shaping drum for attaching the first tire constituent member formed by the molding drum to a second tire constituent member different from the first drum, and concentric with each other An outer shaft of the molding drum disposed in a shape, a hollow shaft disposed in the outer shaft, a central shaft of the shaping drum disposed in the hollow shaft, and a driving means for rotationally driving each shaft A segment drive mechanism for moving the segment in the radial direction,
The segment drive mechanism has a slider that is screwed into a screw groove provided on the outer periphery of the hollow shaft and connected through a groove extending in the axial direction of the outer shaft, and an expansion / contraction mechanism connected to the slider,
The expansion / contraction mechanism moves the segment in the radial direction via the slider by relative rotation between the hollow shaft and the outer shaft, and expands / contracts according to the size of the tread member for forming the forming drum. An unvulcanized tire molding apparatus. In the shaping | molding apparatus of the unvulcanized tire described in Claim 1,
An apparatus for molding an unvulcanized tire, comprising: a conveying device that conveys the molded first tire constituent member to a shaping drum. In the molding apparatus of the unvulcanized tire according to claim 1 or 2,
The driving means for rotationally driving the respective shafts includes a first driving means for driving the outer shaft and a second driving means for driving the hollow shaft, or a common driving for driving the outer shaft and the hollow shaft. Means,
An apparatus for molding an unvulcanized tire, wherein the shaping drum is connected to either the first or second driving means or the common driving means via a clutch means. Conveying the first tire component to the molding drum;
A molding step of rotating the molding drum and pasting and molding the first tire constituent member to the molding drum; a step of transporting the molded first tire constituent member to a shaping drum; and the shaping drum on the shaping drum A method for molding an unvulcanized tire, comprising a step of attaching the molded first tire constituent member to a second tire constituent member different from the first tire constituent member,
Relative rotation of the outer shaft and the hollow shaft among the outer shaft of the molding drum disposed concentrically, the hollow shaft disposed in the outer shaft, and the middle shaft of the shaping drum disposed in the hollow shaft And sliding the slider connected through the groove extending in the axial direction of the outer shaft by screwing into the screw groove provided on the outer periphery of the hollow shaft;
And a step of expanding / contracting the expansion / contraction mechanism of the segment drive mechanism by sliding of the slider to move the segment in the radial direction to expand / contract in accordance with the size of the tread member for forming the forming drum. A method for molding unvulcanized tires. In the molding method of the unvulcanized tire according to claim 4,
A method for molding an unvulcanized tire, comprising a conveying step of conveying the molded first tire constituent member to a shaping drum. In the unvulcanized tire molding device according to any one of claims 1 to 3,
The apparatus for molding an unvulcanized tire, wherein the first tire constituent member is a tread member, and the second tire constituent member is a green case. In the molding method of the unvulcanized tire according to claim 4 or 5,
The method for molding an unvulcanized tire, wherein the first tire constituent member is a tread member, and the second tire constituent member is a green case.

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