Pressure rollers of tire molding machine

Abstract

To provide a pressure roller for a tire molding device that can suppress the detachment of balls from the washer roller. [Solution] The pressing roller 10 of the tire molding apparatus 100 has a plurality of washer rollers 20 provided along the axial direction and relatively slidable radially. The washer roller 20 has an outer ring 21 with an inner groove 21A on its inner circumference, an inner ring 22 provided inside the outer ring 21 with an outer groove 22A on its outer circumference, and a plurality of spheres 23 interposed between the inner groove 21A and the outer groove 22A. The inner ring 22 has insertion holes 22D into which the spheres 23 are inserted between the inner groove 21A and the outer groove 22A.

Description

Technical Field

[0001] The present disclosure relates to a pressing roller of a tire molding apparatus.

Background Art

[0002] A tire molding apparatus is an apparatus for molding a pneumatic tire. The tire molding apparatus includes a drum around which a tire layer in which a plurality of tire constituent rubber members such as an inner liner, carcass, bead, sidewall rubber, belt, and tread are laminated is wound, and a pressing roller that presses the tire layer wound around the drum.

[0003] A plurality of pressing rollers are provided along the axial direction and have washer rollers that are slidable relatively in the radial direction. Thereby, even if the pressing roller is a member whose thickness changes in the width direction like a tire layer in which tire constituent rubber members are laminated, each part in the width direction can be pressed with an appropriate pressing force.

[0004] The washer roller has an outer ring provided with an inner groove in its inner peripheral portion, an inner ring provided inside the outer ring and provided with an outer groove in its outer peripheral portion, and a plurality of balls interposed between the outer groove and the inner groove. Thereby, the outer ring can smoothly slide and rotate with respect to the inner ring via the balls.

[0005] In the washer roller, for example, the balls are made of metal and the outer ring and the inner ring are made of resin. Further, the assembling method of the washer roller is to shift the outer ring and the inner ring and press-fit the balls from the gap between the inner ring and the outer ring.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0007] As mentioned above, if the washer roller's balls are made of metal and the outer and inner rings are made of resin, the sliding motion of the balls can cause wear on either the outer or inner ring, increasing the gap between the outer and inner rings, which can cause the balls to fall out. If a ball falls out of the washer roller, there is a risk that the ball may become mixed into the tire layer, which is made up of multiple rubber components.

[0008] Therefore, the present invention aims to provide a pressing roller for a tire molding apparatus that can suppress the detachment of balls from the washer roller. [Means for solving the problem]

[0009] The pressing roller of the tire molding apparatus according to the present invention has a plurality of washer rollers provided along the axial direction and relatively slidable radially, and the washer roller has an outer ring with an inner groove on its inner circumference, an inner ring provided inside the outer ring with an outer groove on its outer circumference, and a plurality of spheres interposed between the inner groove and the outer groove, and the inner ring is characterized in that insertion holes are formed for inserting the spheres between the inner groove and the outer groove. [Effects of the Invention]

[0010] The pressing roller of the tire molding apparatus of the present invention can suppress the detachment of balls from the washer roller. [Brief explanation of the drawing]

[0011] [Figure 1] This is a schematic diagram showing a pressure roller, which is an example of an embodiment. [Figure 2] This is a front view showing a washer roller, which is an example of an embodiment. [Figure 3] This is a cross-sectional view AA in Figure 2. [Figure 4] This is a perspective view of a lid, which is an example of an embodiment. [Modes for carrying out the invention]

[0012] An example of an embodiment of the present invention will be described in detail below. In the following description, specific shapes, materials, directions, numerical values, etc., are examples provided to facilitate understanding of the present invention and can be appropriately modified according to the application, purpose, specifications, etc.

[0013] [Pressure roller] An example of an embodiment, the pressure roller 10, will be described using Figure 1.

[0014] The pressure roller 10 is a component of the tire molding apparatus 100. The tire molding apparatus 100 is a device for molding pneumatic tires. The tire molding apparatus 100 includes a drum 110 around which a tire layer T, which is made up of multiple unvulcanized tire rubber components such as an inner liner, carcass, bead, sidewall rubber, belt, and tread, is wound, and a pressure roller 10 that presses the tire layer T wound around the drum 110.

[0015] The rubber components of a tire are made by molding unvulcanized rubber into a predetermined shape. Examples of these rubber components include parts for tire components such as the tread and sidewall. These rubber components are formed, for example, by spirally winding rubber strips, which are strip-shaped molded bodies made of unvulcanized rubber, onto a drum 110. These rubber components can also be formed by extruding unvulcanized rubber using an extruder. Note that rubber components in the process of being molded are also unvulcanized rubber components.

[0016] The drum 110 is cylindrical in shape. The tire layer T is wrapped around the outer surface of the drum 110. The drum 110 is driven, for example, by a servo motor, and is rotatable in both directions circumferentially around a rotation axis 111, and its rotational angle position is controllable. The drum 110 may also be divided circumferentially and composed of multiple sectors. The drum 110 may be configured to expand and contract radially as the multiple sectors move radially. This allows the tire molding apparatus 100 to mold the tire layer T into a cylindrical band with any diameter.

[0017] The pressing roller 10 is configured in a cylindrical shape. The pressing roller 10 is disposed, for example, above the drum 110. The pressing roller 10 is movable in a direction approaching or separating from the drum 110. Also, the pressing roller 10 is rotatable about the support shaft 11. The pressing roller 10 is formed to have a length in the axial direction wider than the width of the tire layer T, and presses the drum 110 over the entire width of the tire layer T.

[0018] The pressing roller 10 is composed of a plurality of disk-shaped washer rollers 20 divided in the axial direction. Each washer roller 20 is configured to be slidable relatively in the radial direction. Each washer roller 20 may be supported by the support shaft 11 via a damper such as an air cylinder as a damper. Also, each washer roller 20 may be supported by the support shaft 11 via a spring or the like as an elastic member. Thereby, even for a member whose thickness varies in the width direction like the tire layer T in which the tire constituent rubber members are laminated, each part in the width direction can be pressed with an appropriate pressing force.

[0019] [Washer roller] Using FIGS. 2 and 3, a washer roller 20 which is an example of an embodiment will be described.

[0020] The washer roller 20 is one of the plurality of divisions of the pressing roller 10 in the axial direction as described above. According to the washer roller 20, although details will be described later, the dropping of the balls 23 can be suppressed.

[0021] Hereinafter, each member of the washer roller 20 may be described according to the axial direction (arrow P in the figure), circumferential direction (arrow R in the figure), or radial direction (arrow D in the figure) of the disk-shaped washer roller 20. Also, the inside or outside may be used to describe the radial direction.

[0022] The washer roller 20 comprises an outer ring 21, an inner ring 22, a plurality of spheres 23 interposed between the outer ring 21 and the inner ring 22, and a cover 24 provided on the inner circumference side of the inner ring 22, each of which will be described in detail later.

[0023] The outer ring 21 is a component that forms the inside of the washer roller 20. The outer ring 21 is made of resin, and may be made of nylon, PTFE (polytetrafluoroethylene), or the like. The outer ring 21 is annular in shape and has an inner groove 21A, which will be described in detail later.

[0024] The inner groove 21A is formed on the inner circumference of the outer ring 21 and is the portion on which the spheres 23 slide. The inner groove 21A is formed in an arc shape when viewed in cross-section from the circumferential direction. The inner groove 21A, together with the outer groove 22A of the inner ring 22 (described later), constitutes the ball sliding portion 25. In the ball sliding portion 25, multiple spheres 23 slide against the inner groove 21A of the outer ring 21 and the outer groove 22A of the inner ring 22. As a result, the outer ring 21 slides against the inner ring 22 via the multiple spheres 23 and rotates.

[0025] The inner ring 22 is provided inside the outer ring 21 and is a component that constitutes the inside of the washer roller 20. The inner ring 22 is made of resin, similar to the outer ring 21, and may be made of nylon, PTFE (polytetrafluoroethylene), or the like. The inner ring 22 is disc-shaped and has an outer groove 22A, an opening 22B, a notch 22C, and a mounting hole 22D, which will be described in detail later.

[0026] The outer groove 22A is formed on the outer circumference of the inner ring 22 and is the portion on which the ball 23 slides. The outer groove 22A is formed in an arc shape when viewed in cross-section from the circumferential direction. As described above, the outer groove 22A, together with the inner groove 21A of the outer ring 21, constitutes the ball sliding portion 25.

[0027] The opening 22B is formed in a rectangular shape approximately in the center of the inner ring 22 when viewed from the axial direction. The support shaft 11 of the pressing roller 10 passes through the opening 22B, and an air damper, spring, etc., that supports the washer roller 20 may be provided therein. A notch 22C is formed at the edge of one end of the opening 22B in the longitudinal direction.

[0028] The notch 22C is formed on the inner circumference side of the inner ring 22 by cutting out one longitudinal edge of the opening 22B. An insertion hole 22D communicating with the outer groove 22A is formed on the radially outer end face of the notch 22C. The notch 22C is formed in a convex shape when viewed from the radially inner side. In other words, the notch 22C has stepped portions 22E on both sides in the circumferential direction. Screw holes are provided in the stepped portions 22E into which bolts for fastening the cover 24, which will be described later, are screwed. The notch 22C is closed by the cover 24, which will be described in detail later.

[0029] The insertion hole 22D is a hole for inserting the ball 23 into the outer groove 22A (ball sliding portion 25). The insertion hole 22D allows the ball 23 to be inserted into the ball sliding portion 25 from the inner circumference side of the washer roller 20. As described above, the insertion hole 22D connects the radially outer end face of the notch 22C with the outer groove 22A. The diameter of the insertion hole 22D is larger than the diameter of the ball 23 to be inserted. The insertion hole 22D is closed by a cover 24, which will be described in detail later.

[0030] Multiple spheres 23 are interposed between the outer ring 21 and the inner ring 22. More specifically, the multiple spheres 23 are slidably arranged in a ball sliding section 25, which is formed by the inner groove 21A of the outer ring 21 and the outer groove 22A of the inner ring 22. This allows the outer ring 21 to slide against the inner ring 22 via the multiple spheres 23. As a result, the outer ring 21 rotates by sliding against the inner ring 22 via the multiple spheres 23. The spheres 23 are made of metal, for example, stainless steel.

[0031] Conventionally, when assembling a washer roller, the outer ring was placed on the outside of the inner ring and laid flat on a workbench or the like. The outer ring was then shifted relative to the inner ring until one inner circumference of the outer ring in the radial direction contacted one outer circumference of the inner ring. Balls were then pressed in from the other inner circumference of the outer ring and the outer circumference of the inner ring. In this process, the elasticity of the resin inner and outer rings was used to press in the balls, resulting in balls with a diameter smaller than the maximum diameter that could be placed in the ball sliding section formed by the inner groove of the outer ring and the outer groove of the inner ring. Furthermore, fewer balls than the maximum number that could be placed in the ball sliding section were pressed in.

[0032] Furthermore, conventional washer rollers consist of an outer ring and an inner ring made of resin, and a ball made of metal. As a result of use, the outer ring and inner ring wear down due to the sliding of the ball, and the gap between the inner circumference of the outer ring and the outer circumference of the inner ring widens, which can cause the ball to fall out of the gap. In this case, there is a risk that the ball may get mixed into the tire layer, which is made up of laminated rubber components.

[0033] In the washer roller 20 of this embodiment, the ball 23 can be inserted into the ball sliding portion 25 from the insertion hole 22D. This allows for the insertion of the ball 23 with the largest possible diameter that can be placed in the ball sliding portion 25. In other words, it is possible to insert balls 23 with a larger diameter than conventional balls. This prevents the ball 23 from falling out of the gap between the inner circumference of the outer ring 21 and the outer circumference of the inner ring 22. Furthermore, it is possible to improve the load-bearing capacity of the pressing roller 10.

[0034] Furthermore, in the washer roller 20 of this embodiment, balls 23 can be loaded into the ball sliding portion 25 through the loading hole 22D. This allows for the loading of the maximum number of balls 23 that can be placed in the ball sliding portion 25. In other words, more balls 23 can be loaded than in conventional designs. This improves the load-bearing capacity of the pressing roller 10.

[0035] [lid] An example of an embodiment, the lid 24, will be described using Figures 2 to 4.

[0036] The lid 24 closes the notch 22C and the insertion hole 22D as described above. The lid 24 prevents the ball 23 from falling out of the insertion hole 22D. The lid 24, like the inner ring 22, is made of resin and may be made of nylon, PTFE (polytetrafluoroethylene), or the like. The lid 24 has a body 24A that closes the notch 22C and a projection 24B that closes the insertion hole 22D, which will be described in detail later.

[0037] The main body 24A is formed to the same shape as the notch 22C so as to completely close the notch 22C without any gaps. In other words, the main body 24A is formed to be convex when viewed from the radially inward side. To put it another way, the main body 24A has stepped portions 24C on both sides in the circumferential direction. Holes are provided in the stepped portions 24C through which bolts (not shown) for fastening the cover 24 pass.

[0038] With the above configuration, the bolts that fasten the cover 24 to the inner ring 22 can be fastened from the axial direction of the washer roller 20. Here, both axial sides of the washer roller 20 are in contact with adjacent washer rollers 20, except for the washer rollers 20 at both ends of the pressing roller 10. Therefore, even if a bolt comes loose, it will not fall out because it will be in contact with an adjacent washer roller 20.

[0039] The projection 24B is formed in a substantially cylindrical shape so as to completely seal the insertion hole 22D. The projection 24B protrudes radially outward from the radially outer end face of the main body 24A. The radially outer end face of the projection 24B is formed in an arc shape so as to be continuous with the outer groove 22A of the inner ring 22.

[0040] By adopting the above configuration, a groove similar to that of the outer groove 22A can be formed in the insertion hole 22D of the outer groove 22A of the inner ring 22 into which the projection 24B is inserted. This makes it possible to suppress a decrease in the sliding performance of the ball 23 in the outer groove 22A (ball sliding portion 25).

[0041] [summary] The present invention is further described by the following embodiments. Configuration 1: A pressing roller for a tire molding device, It has multiple washer rollers provided along the axial direction, which are relatively slidable in the radial direction, The washer roller comprises an outer ring with an inner groove on its inner circumference, an inner ring provided inside the outer ring and having an outer groove on its outer circumference, and a plurality of spheres interposed between the inner groove and the outer groove. The inner ring has an insertion hole formed between the inner groove and the outer groove into which the ball is inserted. A pressure roller for a tire molding machine. Configuration 2: The pressing roller described in configuration 1, The inner circumference of the inner ring has a cover that closes the insertion hole. A pressure roller for a tire molding machine. Configuration 3: The pressing roller described in configuration 2, A groove continuous with the outer groove is formed on the surface of the lid that forms the outer groove. A pressure roller for a tire molding machine. Configuration 4: The pressing roller described in configuration 2, The lid is fastened to the inner ring by a fastening member. The fastening member is fastened from the axial direction. A pressure roller for a tire molding machine.

[0042] It should be noted that the present invention is not limited to the embodiments and their modifications described above, and various changes and improvements are possible within the scope of the claims of this application. [Explanation of Symbols]

[0043] 10 Pressing roller, 11 Support shaft, 20 Washer roller, 21 Outer ring, 21A Inner groove, 22 Inner ring, 22A Outer groove, 22B Opening, 22C Notch, 22D Insertion hole, 22E Step, 23 Ball, 24 Cover, 24A Body, 24B Protrusion, 24C Step, 25 Ball sliding part, 100 Tire molding device, 110 Drum, 111 Rotating shaft

Claims

1. A pressing roller for a tire molding device, It has a plurality of washer rollers provided along the axial direction, which are relatively slidable in the radial direction, The washer roller comprises an outer ring with an inner groove on its inner circumference, an inner ring provided inside the outer ring and having an outer groove on its outer circumference, and a plurality of spheres interposed between the inner groove and the outer groove. The inner ring has an insertion hole formed between the inner groove and the outer groove for inserting the ball. A pressure roller for a tire molding machine.

2. A pressing roller according to claim 1, The inner circumference of the inner ring has a cover that closes the insertion hole. A pressure roller for a tire molding machine.

3. A pressing roller according to claim 2, A groove continuous with the outer groove is formed on the surface of the lid that forms the outer groove. A pressure roller for a tire molding machine.

4. A pressing roller according to claim 2, The lid is fastened to the inner ring by a fastening member. The fastening member is fastened from the axial direction. A pressure roller for a tire molding machine.

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