Deflection roller, use of said deflection roller and tire building machines comprising said deflection roller

Abstract

A deflection roller for guiding and/or deflecting a rubber tire component, has a shaft that defines an axis of rotation of the deflection roller and a plurality of bristles distributed circumferentially around the shaft and extending radially outwards and orthogonally with respect to the axis of rotation to form a circumferential brush surface that is concentric to the axis of rotation. The deflection roller further has a first boundary element and a second boundary element extending adjacent to the plurality of bristles in an axial direction parallel to the axis of rotation and protruding radially outside the circumferential brush surface at a first end and a second end of the circumferential brush surface, respectively, for binding the circumferential brush surface in the axial direction.

Claims

1. A deflection roller for guiding or deflecting a rubber tire component, wherein the deflection roller comprises a shaft that defines an axis of rotation of the deflection roller and a plurality of bristles distributed circumferentially around the shaft and extending radially outwards and orthogonally with respect to the axis of rotation to form a circumferential brush surface that is concentric to the axis of rotation, wherein the deflection roller further comprises a first boundary element and a second boundary element extending adjacent to the plurality of bristles in an axial direction parallel to the axis of rotation and protruding radially outside the circumferential brush surface at a first end and a second end of the circumferential brush surface, respectively, for binding the circumferential brush surface in the axial direction.

2. The deflection roller according to claim 1, wherein the bristles extend in a substantially neutral orientation that does not actively steer the rubber tire component in an axial direction parallel to the axis of rotation.

3. The deflection roller according to claim 1, wherein the deflection roller comprises a bristle holder for holding and positioning the plurality of bristles with respect to the shaft, wherein the plurality of bristles are mounted orthogonally to the bristle holder.

4. The deflection roller according to claim 1, wherein the bristles of the plurality of bristles are flexible.

5. The deflection roller according to claim 1, wherein the bristles of the plurality of bristles are resilient.

6. The deflection roller according to claim 1, wherein the circumferential brush surface is straight cylindrical or has a constant diameter in the axial direction.

7. The deflection roller according to claim 1, wherein all bristles of the plurality of bristles have the same length.

8. The deflection roller according to claim 1, wherein the first boundary element and the second boundary element comprise a first boundary surface and a second boundary surface, respectively, protruding radially outside the circumferential brush surface in an upright orientation with respect to the circumferential brush surface.

9. The deflection roller according to claim 8, wherein the first boundary surface and the second boundary surface extend circumferentially or concentrically with respect to the circumferential brush surface.

10. The deflection roller according to claim 8, wherein the first boundary element and the second boundary element comprise a first disc forming the first boundary surface and a second disc forming the second boundary surface, respectively, each disc having a circumferential edge extending concentrically with respect to and radially outside of the circumferential brush surface.

11. The deflection roller according to claim 1, wherein the first boundary element and the second boundary element protrude radially outside the circumferential brush surface over a distance that is at least equal to the thickness of the rubber tire component which the deflection roller is arranged to guide or deflect.

12. The deflection roller according to claim 1, wherein the first boundary element and the second boundary element protrude radially outside the circumferential brush surface over at least ten millimeters at least twenty millimeters or at least thirty millimeters.

13. The deflection roller according to claim 1, wherein the first boundary element and the second boundary element are mounted to the shaft.

14. The deflection roller according to claim 13, wherein the deflection roller comprises a bristle holder for holding and positioning the plurality of bristles with respect to the shaft, wherein the plurality of bristles are mounted orthogonally to the bristle holder, wherein the bristle holder is mounted to and extends between the first boundary element and the second boundary element in a position radially outside or spaced apart from the shaft.

15. The deflection roller according to claim 1, wherein the shaft is a hollow shaft or a tube.

16. A tire building machine comprising the deflection roller according to claim 1.

17. The tire building machine according to claim 16, wherein the tire building machine comprises a festooner, wherein festooner comprises a plurality of said deflection rollers.

18. The tire building machine according to claim 16, wherein the tire building machine comprises a dancer roller assembly, wherein the deflection roller is a dancer roller of said dancer roller assembly.

19. The tire building machine according to claim 18, wherein the dancer roller assembly comprises guides, wherein the deflection roller is slidable along the guides in a dancing direction, wherein the deflection roller is tiltable about a tilting axis that extends perpendicular to the axis of rotation and perpendicular to the dancing direction.

20. A method for guiding or deflecting a rubber tire component from a first direction of conveyance to a second direction of conveyance which is different from the first direction of conveyance, in a tire building machine, while containing the rubber tire component on the circumferential brush surface between the first boundary element and the second boundary element, which comprises providing a deflection roller which comprises a shaft that defines an axis of rotation of the deflection roller and a plurality of bristles distributed circumferentially around the shaft and extending radially outwards and orthogonally with respect to the axis of rotation to form a circumferential brush surface that is concentric to the axis of rotation, wherein the deflection roller further comprises a first boundary element and a second boundary element extending adjacent to the plurality of bristles in an axial direction parallel to the axis of rotation and protruding radially outside the circumferential brush surface at a first end and a second end of the circumferential brush surface, respectively, for binding the circumferential brush surface in the axial direction, and guiding or deflecting the rubber tire component using the deflection roller.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention will be elucidated on the basis of an exemplary embodiment shown in the attached schematic drawings, in which:

(2) FIG. 1 shows an isometric view of a deflection roller according to the invention;

(3) FIG. 2 shows a cross section of the deflection roller according to the line II-II in FIG. 1;

(4) FIG. 3 shows a cross section of the deflection roller according to the line III-III in FIG. 2;

(5) FIG. 4 shows a first tire building machine, in particular a festooner, with a plurality of the deflection rollers according to FIG. 1;

(6) FIG. 5 shows a second tire building machine, in particular a dancer roller assembly with the deflection roller according to FIG. 1; and

(7) FIGS. 6A and 6B show two steps in the operation of the deflection roller in the dancer roller assembly according to FIG. 5.

DETAILED DESCRIPTION OF THE INVENTION

(8) FIGS. 1, 2 and 3 show a deflection pulley or a deflection roller 1 according to the invention. The deflection roller 1 can be applied, implemented or used in various tire building machines for guiding and/or deflecting a rubber tire component 9. FIG. 4 show an exemplary use of a plurality of the deflection rollers 1 according to FIGS. 1-3 in a festooner 81. FIG. 5 shows an alternative exemplary use of the deflection roller 1 in a dancer roller assembly 85.

(9) The rubber tire component 9 is a substantially continuous, strip-like element that is supplied from an upstream station, e.g. an extruder, or a storage reel. The rubber tire component 9 is shown in cross section in FIG. 2. In this exemplary embodiment, the rubber tire component 9 comprises a body of rubber material 90 and a plurality of reinforcement cords 91 embedded in said body of rubber material 90. The body of rubber material 90 has a main surface 92 facing towards and contacting the deflection roller 1 in a manner which will be described hereafter in more detail.

(10) As shown in FIGS. 1-3, the deflection roller 1 comprises a central axle or shaft 2 that defines an axis of rotation S of the deflection roller 1, an axial direction A parallel to, in-line with or along the axis of rotation S and a radial direction R. In the context of the invention, radially is not intended to mean strictly orthogonal to the axis of rotation S, but is to interpreted as extending in a radial manner outward or away from a center, in this case the axis of rotation S. The shaft 2 is hollow or tubular to allow for the deflection roller 1 to be rotatably mounted on a shaft of the tire building machine (not shown). Alternatively, the shaft 2 may protrude towards the tire building machine, with the tire building machine being provided with suitable receptacles (not shown) for rotatably receiving the shaft 2.

(11) The deflection roller 1 is provided with a plurality of bristles 3 which are distributed evenly in a circumferential direction around the axis of rotation S. All of the plurality of bristles 3 are of the same or substantially the same length so that the distal or free ends thereof in the radial direction R together form a circumferential brush surface 4 for supporting the rubber tire component 9 thereon. The circumferential brush surface 4 extends concentrically to the axis of rotation S at a first diameter D1. As shown in cross section in FIGS. 2 and 3, the deflection roller 1 is provided with a bristle holder 5 for holding and positioning the plurality of bristles 3 with respect to the shaft 2. Each bristle 3 of the plurality of bristles 3 is mounted orthogonally with respect to the axis of rotation S to the bristle holder 5 such that at least the radially inner part of the bristles 3, proximal to the bristle holder 5, extends orthogonal to or substantially orthogonal to the axis of rotation S. The bristles 3 are given a neutral orientation with respect to the axis of rotation, e.g. each bristle 3 extending in a plane that is at a right angle with respect to the axis of rotation. Preferably, in an unbend or unflexed state, each bristle 3 extends outwards in the radial direction R orthogonally or substantially orthogonally with respect to the axis of rotation S. The bristles 3 in this exemplary embodiment extend neutrally orthogonally outward and are not given a specific oblique orientation or offset with respect to the orthogonal direction. The bristles 3 are thus only arranged for passively supporting the rubber tire component 9 without actively steering it in the axial direction A.

(12) The bristles 3 of the plurality of bristles 3 are strong enough or stiff enough in the radial direction R for in combination supporting the rubber tire component 9 around the circumferential brush surface 4 in a stable manner at or near the first diameter D1. Each bristle 3 of the plurality of bristles 3 is however flexible enough in the axial direction A to individually and at least partially move with the rubber tire component 9 in the axial direction A in the event that the rubber tire component 9 is displaced or runs out of alignment in said axial direction A with respect to the deflection roller 1. As such, the bristles 3 do not cause or considerably reduce the amount of friction between the rubber tire component 9 and the circumferential brush surface 4 in the axial direction A in the event that the rubber tire component 9 starts to run out of alignment in the axial direction A with respect deflection roller 1. The bristles 3 are resiliently flexible, in the sense that they in normal use only bent or flex within their elastic range and return to the unbend or unflexed state as soon as the force that causes the bending or flexing is removed. In practice, this means that the bristles 3 will move with the tire component 9 in the axial direction A as long as the bristles 3 are in contact with the main surface 92 of the rubber tire component 9, but as soon as the contact is terminated, each bristle 3 will immediately and/or individually return to its respective unbend or unflexed state.

(13) As shown in FIGS. 1-3, the deflection roller 1 further comprises a first boundary element 6 and a second boundary element 7 that bind or enclose the circumferential brush surface 4 in the axial direction A. The circumferential brush surface 4 extends in the axial direction A in between the first boundary element 6 and the second boundary element 7. As best seen in FIG. 2, the first boundary element 6 extends adjacent to the plurality of bristles 3 in the axial direction A and extends radially outwards in the radial direction R to a position outside the circumferential brush surface 4. The first boundary element 6 is provided with a disc-shaped, a disc-like body or a disc 60 that is concentrically mounted to or with respect to the shaft 2. The disc 60 has a first circumferential edge 61 that extends concentrically with respect to and protrudes radially outside of the circumferential brush surface 4 at a second diameter D2. The disc 60 forms a first boundary surface 62 opposite to the rubber tire component 9 in the axial direction A at a first end of the circumferential brush surface 4. The first boundary surface 6 stands up vertically upright with respect to the circumferential brush surface 4 over a distance that is at least equal to the thickness of the tire component 9 in the radial direction R. In this example, the disc 60 is chamfered above said thickness.

(14) The second boundary element 7 is mirror symmetrical to the first boundary element 6 in a mirror plane perpendicular to the axis of rotation S. As such, the second boundary element 7 also comprises a disc 70 that is concentrically mounted to or with respect to the shaft 2 at a second end of the circumferential brush surface 4 in the axial direction A with respect to the first end and the first boundary element 6. The disc 70 of the second boundary element 7 similarly has a second circumferential edge 71 and a second boundary surface 72 opposite to the rubber tire component 9 in the axial direction A at the second end of the circumferential brush surface 4.

(15) The first boundary element 6 and the second boundary element 7 protrude radially outside the circumferential brush surface 4 from the first diameter D1 up to the second diameter D2 over a protrusion distance X. The protrusion distance X is at least equal to the thickness of the rubber tire component 9 which the deflection roller 1 is arranged to guide and/or deflect. The protrusion distance X in this example is approximately thirty (30) millimeters.

(16) As shown in FIG. 2, the bristle holder 5 is mounted to and extends between the first boundary element 6 and the second boundary element 7 in a position in the radial direction R outside of or spaced apart from the shaft 2. Thus, the bristles 3 do not necessarily have to originate from the shaft 2 but can be supported on or mounted to the bristle holder 5 at a radial distance from the shaft 2, thereby reducing the length of the bristles 3 in the radial direction R between their respective bases and the circumferential brush surface 4.

(17) The operation of the aforementioned deflection roller 1 will now be described with reference to FIGS. 1, 2 and 3.

(18) As described before, the bristles 3 as shown in FIGS. 1, 2 and 3 individually do not generate a significant amount of resistance against movement of the rubber tire component 9 in the axial direction A. The reduced friction between the circumferential brush surface 4 and the rubber tire component 9 as a result of the resilient flexibility of the individual bristles 3 allows for the rubber tire component 9 to run out of alignment with respect to the deflection roller 1 in the axial direction A without severe consequences to the quality or consistency of the rubber tire component 9. In particular, the boundary elements 6, 7 allow for correction of the misalignment of the rubber tire component 9 by simply stopping and/or reversing the movement of rubber tire component 9 in the axial direction A as soon as the rubber tire component 9 hits or starts to abut the boundary surfaces 62, 72 of one of the boundary elements 6, 7.

(19) Again, because of the minimal friction between the circumferential brush surface 4 and the rubber tire component 9, the reaction force alone, as exerted by the one boundary element 6, 7 upon the rubber tire component 9, is enough to stop and/or reverse the movement of the rubber tire component 9 in the axial direction A. During the running out of alignment of the rubber tire component 9 in the axial direction A, the bristles 3 individually come into contact and are eventually individually released out of contact with the rubber tire component 9, which allows the bristles 3 to return to the unbend or unflexed state, ready for renewed contact with the rubber tire component 9 when the continuous length of the rubber tire component 9 start to run out of alignment in the opposite axial direction A.

(20) FIG. 4 shows the festooner 81 and the use of a plurality of the aforementioned deflection rollers 1 in said festooner 81. The festooner 81 comprises an upright column 82 for supporting an upper support member 83 and a lower support member 84. A plurality of the deflection rollers 1 according to FIGS. 1, 2 and 3 is mounted to each of the support members 83, 84 to form a guide path P for the rubber tire component 9 that alternatingly zigzags between the deflection rollers 1 at the upper support member 83 and the lower support member 84. The support members 83, 84 are arranged to be reciprocally moved to and fro each other in a vertical direction along the column 82 to decrease and increase, respectively, the capacity of the festooner 81. At each of the deflection rollers 1, the rubber tire component 9 is deflected around the circumferential brush surface 4 of the respective deflection roller 1 over an angle of at least one-hundred-and-eighty (180) degrees with respect to the axis of rotation S from a first direction of conveyance to an opposite second direction of conveyance. Thus, the main surface 92 of the rubber tire component 9 contacts at least a half circumference of the circumferential brush surface 4.

(21) In particular in situations when the capacity of the festooner is increased or decreased, the rubber tire component 9 is subjected to various forces that could potentially cause the rubber tire component 9 to run out of alignment. The use of a plurality of said deflection roller 1 in a festooner 81 is particularly advantageous as the plurality of deflection rollers 1 are able to automatically correct any running out of alignment of the rubber tire component 9, without significant friction and thus without causing permanent stretching and/or deformation of the rubber tire component 9 or the reinforcement cords 91 embedded in the rubber tire component 9. In particular the occurrence of waving as a result of uneven stretching of the reinforcement cords 91 in the longitudinal direction of the rubber tire component 9 can be reduced or prevented.

(22) FIG. 5 shows a dancer roller assembly 85 and the use of the aforementioned deflection roller 1 as a dancer roller in said dancer roller assembly 85. A dancer roller is typically used in tire building applications just upstream of a station where abrupt changes in the feeding velocity of the rubber tire component 9 are required to accommodate an intermittent process, e.g. at a cutting station where lengths of the rubber tire component 9 are fed onto a cutting table and cut into smaller pieces. The deflection roller 1 in its function as dancer roller is mounted to vertically extending guides 88, 89 and is arranged to rapidly move in an up and down dancing direction E along the guides 88, 89 with respect to a set of stationary rollers 86, 87 to briefly accumulate a length of the rubber tire component 9 in a loop L between the stationary rollers 86, 87 before feeding it downstream. At the deflection roller 1, the rubber tire component 9 is deflected around the circumferential brush surface 4 of the deflection roller 1 over an angle of at least one-hundred-and-eighty (180) degrees with respect to the axis of rotation S from a first direction of conveyance to an opposite second direction of conveyance. Thus, the main surface 92 of the rubber tire component 9 contacts at least a half circumference of the circumferential brush surface 4. The rapid movement can cause running out of alignment of the rubber tire component 9 with respect to the deflection roller 1, which because of the reduced friction can be corrected by the deflection roller 1 without serious deformation and/or stretching of the rubber tire component 9.

(23) A traditional dancer roller is only movable in the up and down dancing direction E. FIGS. 6A and 6B show a possible configuration of the deflection roller 1 according to the invention, which contrary to the traditional dancer rollers, is tiltable about a tilting axis T, in addition to the up and down movement in the dancing direction E. The tilting axis T extends perpendicular to the axis of rotation S and perpendicular to the dancing direction E of the deflection roller 1. By tilting the deflection roller 1 about the tilting axis T, asymmetries, tilting, warping and/or uneven tensions in the rubber tire component 9 can be compensated for at the deflection roller 1.

(24) As schematically shown in FIGS. 6A and 6B, the shaft 2 of the deflection roller 1 is mounted in a tiltable manner to the guides 88, 89 via a set of concave/convex slidable and/or rotational bearings 98, 99. The concave parts of the bearings 98, 99 are mounted to the guides 88, 89 so as to be slidable up and down in the dancing direction E along the guides 88, 89. The convex parts of the bearings 98, 99 are mounted to the shaft 2 via further rotational bearings to allow rotation of the shaft 2 with respect to the convex parts of the bearings 98, 99 about the rotational axis S. The concave parts of the bearings 98, 99 are concentrically shaped with respect to the tilting axis T, while the convex parts of the bearings 98, 99 are slidably placed or received within the concave parts so as to be tiltable about the tilting axis T. As a result, the deflection roller 1 is rotatable or tiltable about the tilting axis T within a tilting range of approximately zero (0) to fifteen (15) degrees with respect to the neutral or horizontal position. The deflection roller 1 automatically tilts with the rubber tire component 9 and thus effectively follows the rubber tire component 9 when asymmetries, tilting, warping and/or uneven tensions occur in the rubber tire component 9. By having the tiltable deflection roller 1, the risk of the rubber tire component 9 running of the side of the deflection roller 1 can be reduced.

(25) It is to be understood that the above description is included to illustrate the operation of the preferred embodiments and is not meant to limit the scope of the invention. From the above discussion, many variations will be apparent to one skilled in the art that would yet be encompassed by the scope of the present invention.