FIELD OF THE INVENTION

[0001] The present invention relates generally to support rollers in the manufacturing of bands for retread tires. More particularly, the present application involves a support roller that supports the band when adhesive is applied to the underside of the band.

BACKGROUND

[0002] Retreaded tires are those that have a new tread section placed onto a carcass of the tire after the tread section currently on the tire is worn down. To make this replacement, the tread currently on the tire may be removed, and the outer surface of the carcass treated for acceptance of the new tread. A layer of adhesive, such as cushion gum or rubber cement adhesive, can be applied to the surface of the carcass and the new tread section may be applied to this adhesive layer. The adhesive layer can be cured in order to cause the new tread section to be attached to the carcass.

[0003] The new tread section can be a cured piece of rubber that is formed by a mold and a press. This piece of cured rubber is often referred to as a band or a retread band. Once molded, the band is transferred between an adhesive application roller and a support roller in which the underside surface of the band engages the adhesive application roller, and the tread surface of the band engages the support roller. A second roller on the underside surface side may also be present and may be in engagement with the adhesive application roller to form a nip to better control the adhesive application. Adhesive is poured or otherwise transferred onto the underside surface or the application roller and pressure from the application roller functions to spread the adhesive evenly over the underside surface.

[0004] The underside surface often is not flat and has a curved profile. In order to address this issue so that the adhesive is evenly spread over the underside surface, the application roller can be rubber coated to allow a certain amount of flex to conform to the uneven underside surface. Even with this feature, the adhesive may not be spread evenly onto the underside surface of the band. Another fix is to raise the low spots of the underside surface by wrapping the support roller with duct tape in areas that correspond to the low spots on the underside surface. Although this technique may raise the underside surface at the low spots, it also causes other areas that are not low spots of the underside surface to be undesirably raised. This is because the application of duct tape is not precise and is unable to be placed at exactly the right spot. Also, one is limited to the use of the actual thickness of the duct tape and cannot build up the support roll to diameters other than those mandated by the thickness of one layer of duct dape wrapped one or more times about the support roll. The duct tape is applied to the support roller in grooved areas because they are next to tread areas and the duct tape is not capable of being precisely applied in the axial direction. The use of duct tape is time consuming, imprecise, and is unable to reproduce consistent results in the spreading of adhesive over the underside surface of different band types. As such, there remains room for variation and improvement within the art.

BRIEF DESCRIPTION OF THE DRAWINGS

[0005] A full and enabling disclosure of the present invention, including the best mode thereof, directed to one of ordinary skill in the art, is set forth more particularly in the remainder of the specification, which makes reference to the appended Figs, in which:

[0006] Fig. 1 is a top view of a retread band supported by a support roller.

[0007] Fig. 2 is a side view of the retread band and support roller of Fig. 1 with the addition of an adhesive application roller and a second roller on the underside surface of the retread band.

[0008] Fig. 3 is a cross-sectional view taken along line 3-3 of Fig. 2.

[0009] Fig. 4 is a perspective view of a support roller.

[0010] Fig. 5 is a side view of the support roller of Fig. 4 with hose clamps attached.

[0011] Fig. 6 is a front view of the support roller of Fig. 4.

[0012] Fig. 7 is a cross-sectional view taken along line 7-7 of Fig. 6.

[0013] Repeat use of reference characters in the present specification and drawings is intended to represent the same or analogous features or elements of the invention. DETAILED DESCRIPTION OF REPRESENTATIVE EMBODIMENTS

[0014] Reference will now be made in detail to embodiments of the invention, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation of the invention, and not meant as a limitation of the invention. For example, features illustrated or described as part of one embodiment can be used with another embodiment to yield still a third embodiment. It is intended that the present invention include these and other modifications and variations.

[0015] The present invention provides for a support roller 10 that is used in an adhesive application stage in the production of retread bands 12. The retread band 12 is transferred over the support roller 10 and supported thereon as the adhesive application roller 94 engages the underside surface 24 of the retread band 12 and applies adhesive 26. The support roller 10 has an engagement zone 16 that engages a tread surface 22 of the retread band and has a profile that matches the profile of the tread surface 22. The tread surface 22 has one or more grooves 28 that are within the width 34 of the tread surface 22 that engages the engagement zone 16. However, the profile of the engagement zone 16 at the grooves 28 is not the profile of the grooves 28. The support roller 10 raises the underside surface 24 so that high and low spots on the underside surface 24 are eliminated to allow the adhesive application roller 94 to apply the adhesive 26 in a more consistent and even manner across the underside surface 24.

[0016] Fig. 1 shows an adhesive application stage of the retread process in which a pressed and cured retread band 12 is transported on a plurality of transport rollers 98 to the adhesive application stage. The adhesive application roller 94 and the applied adhesive 26 are not shown in this figure for purposes of clarity. In the adhesive application stage the retread band 12 is engaged by the support roller 10 on one side, and by the adhesive application roller 94 on the opposite side. The retread band 12 can move in the direction of the arrows A in Fig. 1 across the support roller 10. The underside surface 24 of the retread band 12 is shown in Fig. 1, and it is this surface onto which the adhesive 26 is applied. The support roller 10 may have a drive shaft 80 that extends in the axial direction 18 of the support roller 10. A belt 92 engages and wraps around the drive shaft 80 and is tied onto a motor 90 to place the motor 90 into communication with the drive shaft 80. Rotation of the motor 90 is translated to the drive shaft 80 via the belt 92 in order to rotate the drive shaft 80 to in turn cause the support roller 10 to rotate. The drive shaft 80 can be mounted onto bearings 100 to allow the drive shaft 80 to rotate. [0017] Fig. 2 is a side view of the adhesive application stage of Fig. 1 without the bearing 100 being shown for purposes of clarity. The adhesive application roller 94 and the second roller 96 are shown as well as a dispenser for the adhesive 26. The adhesive 26 may be dispensed onto the adhesive application roller 94 and this roller 94 can be in engagement with the second roller 96. The nip formed between rollers 94 and 96 may be present to help better control the spreading and amount of adhesive 26 applied. The adhesive 26 can be rubber cement adhesive, or any type of adhesive capable of being used with a retread band 12. The adhesive application roller 94 can be rubber coated and adhesive 26 present on its surface may be transferred onto the underside surface 24 as the underside surface 24 passes across and engages the adhesive application roller 94. The adhesive application roller 94, second roller 96, transport rollers 98, motor 90, and other components of the described arrangement may be provided as a 775 adhesive spreader, or other adhesive spreader manufactured by Black Bros. Co., having offices located at 501 Ninth Avenue, Post Office Box 410, Mendota, Illinois, 61342-0410, USA.

[0018] The tread surface 22 does not engage the adhesive application roller 94 and is on a side of the retread band 12 opposite from the underside surface 24. The support roller 10 engages the retread band 12 directly opposite from the engagement of the adhesive application roller 94 to the retread band 12. The transport rollers 98 engage the tread surface 22 on opposite sides of the support roller 10 in the direction of travel A, and any number of transport rollers 98 may be present.

[0019] Fig. 3 is a cross-sectional view of the support roller 10 with the supported retread band 12 and adhesive application roller 94. The support roller 10 has an outer surface 14 that extends in the axial direction 18 of the support roller 10 between a first terminal end 50 and a second terminal end 52. The engagement zone 16 is the portion of the outer surface 14 that is configured to engage the tread surface 22. The engagement zone 16 does not extend across the entire outer surface 14 but is spaced some amount from the first terminal end 50 in the axial direction 18, and is spaced some amount from the second terminal end 52 in the axial direction. In other instances, the engagement zone 16 may extend across the entire outer surface 14.

[0020] The profile of the outer surface 14 in the engagement zone 16 is the diameter 36 of the outer surface 14 as it extends across the engagement zone 16 in the axial direction 18. The diameter 36 is not the same across the entire engagement zone 16 but instead changes so as to be larger and smaller at different axial locations in the engagement zone 16. The diameter 36 is the distance of the outer surface 14 perpendicular to the axial direction 18 through the axis of rotation of the support roller 10. The profile may be the same in some portions of the

engagement zone 16 but not in all portions of the engagement zone 16. In this regard, some axial length of the engagement zone 16 may have the same diameter 36 but at some point it will change so that the diameter 36 is different for some other length of the engagement zone 16. The diameter 36 is the same in the circumferential direction 20 completely about the outer surface 14 at any given axial location of the outer surface 14 in the engagement zone 16.

[0021] The outer surface 14 features a first ear 54 and a second ear 56 that are spaced from one another in the axial direction 18. The ears 54, 56 have diameters 36 that are

significantly larger than the other areas of the outer surface 14 and thus appear to be prominent features of the support roller 10. Although two ears 54, 56 are present, any number of ears can be present in other versions of the support roller 10 - such as one ear, three ears, or even zero ears. The two ears 54, 56 are located on opposite ends of the engagement zone 16 in the axial direction 18. The engagement zone 16 has a first terminal end 46 that is located at the first ear 54. A second terminal end 48 of the engagement zone 16 is located at the second ear 56.

Portions of the first ear 54 and the second ear 56 may form part of the engagement zone 16, while other portions of the first ear 54 and the second ear 56 do not form part of the engagement zone 16 and are outboard from the engagement zone 16 in the axial direction 18. The greatest diameter 36 of the outer surface 14 may be at one of, or at both of the ears 54 or 56.

[0022] The engagement zone 16 has an interior section 58 that spans the distance between the first ear 54 and the second ear 56 in the axial direction 18. The diameter 36 of the interior section 58 is less than the diameter 36 of the ears 54, 56. However, in some

embodiments, the diameter 36 at certain locations of the interior section 58 may in fact be greater than the maximum diameters of one or both of the ears 54, 56. Also, at certain portions of the interior section 58 the diameter 36 may be greater than the diameter 36 of one or more portions of the ears 54, 56. The diameter 36 at the interior section 58 varies across the total length of the interior section 58 in the axial direction 18, although it may be the same at certain locations and for certain lengths in the axial direction 18.

[0023] The retread band 12 has a retread band width 44 that is oriented in the axial direction 18 as the retread band 12 moves through the adhesive application stage. The tread surface 22 has a width 34 that extends the entire retread band width 44 so that both of these widths 44, 34 are the same distance. In other versions, the width 34 of the tread surface 22 is less than the full width 44 of the retread band 12. The width 34 of the tread surface 22 may be the same as the width of the engagement zone 16 so that the tread surface 22 is engaged by the outer surface 14 along the entire width 34. The diameter 36 across the width of the engagement zone 58 is selected based upon the profile of the tread surface 22 along its width 34 so that support is given to the retread band 12 to lift the underside surface 24 the proper amount to present a flat surface onto which the adhesive application roller 94 can engage. The low spots of the tread surface 22 are thus supported up a required amount to achieve this level underside surface 24. The ends of the retread band 12 that are the two outboard ends are often referred to as wings, and these two wings may have a tendency to curl downward thus causing the support roller 10 to feature the two ears 54, 56 that have a greater diameter 36 than other areas in order to support the two wings to achieve a level underside surface 24.

[0024] The profile of the outer surface 14 in the engagement zone 16 is thus sized to match the profile of the cross-section of the retread band 12. The exception to this lies in the grooves 28 of the retread band 12. The groove 28 is open at the tread surface 22 and closed in the direction towards the underside surface 24 which is in the radial direction in Fig. 3. The groove 28 is defined by a pair of tread blocks 40 that are located on opposite sides of the groove 28 in the direction 42 which is the direction of the width 34 of the tread surface 22. The direction 42 is the same direction as the axial direction 18 as shown in Fig. 3. The groove 28 is thus any opening on the tread surface 22 that extends towards the underside surface 24 bordered by tread blocks 40 on either side in the direction 42. The groove 28 may extend in the circumferential direction 20 around the entire tire when the retread band 12 is attached to the carcass. The profile of the outer surface 14 in the engagement zone 16 does not match the profile of the groove 28 in the engagement zone 16. The outer surface 60 of the engagement zone 16 is identified in Fig. 3, and the diameter 36 at the outer surface 60 may be the same across its entire width 38, or the diameter 36 can change along the width 38 so that it is larger and smaller at different locations in the axial direction 18. As shown in Fig. 3, the diameter 36 is the same across the entire width 38 of the groove 28.

[0025] The outer surface 14 extending in the axial direction 18 from the first ear 54 to the second ear 56 changes in diameter 36 to match the shape of the tread surface 22 until reaching the groove 28. The outer surface 62 is the location of the outer surface 14 immediately adjacent the outer surface 60 and has a diameter 36 that still matches the profile shape of the tread surface 22. The diameter 36 of the outer surface 60 may be the same size as the diameter 36 of the outer surface 62. As such, once reaching the groove 28, the diameter 36 of the outer surface 14 may continue on as the same size across the full width 38 and then resume changing in size based upon the profile of the tread surface 22 outside of the groove 28. Although described as having the same diameter 36 across the entire width 38 of the groove 28, it is to be understood that the diameter 36 at the outer surface 60 may change across its length in the axial direction 18 so as to be greater or smaller at various points in accordance with other exemplary embodiments.

[0026] The outer surface 14 upon extending beyond the groove 28 in the axial direction 18 may resume assuming a complimentary shape to the tread surface 22 such that its diameter 36 will change. Any number of grooves 28 can be present in the tread surface 22 in accordance with various exemplary embodiments. In the embodiment shown, the groove 28 is a first groove 28, and a second groove 30 and a third groove 32 are also shown. Second and third grooves 30 and 32 are defined by a pair of tread blocks 40 on either side and are open at the tread surface 22 and are closed at their ends proximate to the underside surface 24. The outer surface 14 at the location of the second and third grooves 30, 32 is not profiled to match the shape and size of the second and third grooves 30, 32 but is straight and at a diameter 36 that is the same as the outer surface 14 engaging the tread surface 22 located immediately adjacent each one of these grooves 30, 32. The outer surface 14 at the second and third grooves 30, 32 may be arranged in the manners previously discussed with respect to the outer surface 60 at the first groove 28 and a repeat of this information is not necessary.

[0027] It is to be understood that in some embodiments of the support roller 10, that the outer surface 14 at one or more of the grooves 28 does in fact have a profile that matches the profile of the one or more grooves 28 and engages the retread band 12 at these locations.

However, the support roller 10 is designed so that at least one of the grooves 28 corresponds to a section of the outer surface 14 that is not sized and shaped to match the size and shape of the at least one groove 28. The support roller 10 results in a design in which the profile of the outer surface 14 in the engagement zone 16 matches the complimentary profile of the tread surface 22 along a portion of the width 34 of the tread surface 22 but not along all of the width 34 of the tread surface 22. [0028] In order to construct the profile of the engagement zone 16, a laser profilometer scan of the tread surface 22 may be conducted. This scan can then be used to cut the engagement zone 16 into the support roller 10 by the use of a lathe. The engagement zone 16 can then have a negative profile of the tread surface 22, with the exception of portions related to the groove 28. The 3D scan of the tread surface 22 allows for a precise and consistent lifting of the retread band 12 by the support roller 10 as the engagement zone 16 is constructed to precisely match the profile of the tread surface 22 other than locations including the grooves 28. Although the profile of the tread surface 22 may change in the machine direction, the profile of the

engagement zone 16 of the support roller 10 does not change but remains the same as the profile measured at a particular cross-section of the tread surface 22. In this regard the diameter 36 is the same about the engagement zone 16 for 360 degrees about the support roller 10 at a particular location in the axial direction 18 of the engagement zone 16.

[0029] The support roller 10 can be a single piece that is mounted to the bearings 100, or may be made of multiple pieces. For example, the main body of the support roller 10 can be one component with the drive shaft 80 a separate piece that is attached to this main body. Figs. 4-7 show another arrangement of the support roller 10 in which it is made from multiple

components. The support roller includes a drive tube 66 onto which a collar 64 is mounted. The collar 64 may be attached to and removed from the drive tube 66 as desired. The engagement zone 16 is located on the collar 64 so that when a different type of retread band 12 with a different tread surface 22 profile is desired to be run through the adhesive application stage, the collar 64 can be removed from the drive tube 66 and a new collar 64 with the complimentary engagement zone 16 attached. With reference in particular to Fig. 7, the drive shaft 80 is a single component that extends in the axial direction 18 through the axis of rotation of the support roller 10. A first drive side insert 82 and a second drive side insert 88 are mounted to the exterior 86 of the drive shaft 80 and are free from engagement with one another and are spaced from one another in the axial direction 18. The inserts 82, 88 are attached to the drive shaft 80 so that they are rigidly mounted onto the drive shaft 80 and do not rotate relative to the drive shaft 80. A drive tube 66 engages and is mounted to the first and second drive side inserts 82, 88 and rotate with the inserts 82, 88 as they are rotated. The interior 84 of the drive tube 66 engages the first and second drive side inserts 82, 88, but is spaced in the radial direction from and does not engage the exterior 86 of the drive shaft 80. Attachment to the inserts 82, 88 may be through interference fit, or through the use of mechanical fasteners.

[0030] Rotation of the drive shaft 80 is communicated through the first and second drive side inserts 82, 88 to the drive tube 66 to in turn cause it to rotate. A step 68 is defined on the exterior surface of the drive tube 66, and no portion of the exterior surface of the drive tube 66 is shaped so as to be complimentary with the profile of the retread band 12. The step 68 is an area of lesser diameter of the exterior surface of the drive tube 66 than other areas of the exterior surface of the drive tube 66 on either side of the step 68 in the axial direction 18. The collar 64 rests within the step 68, and the areas of the drive tube 66 on either side of the step 68 in the axial direction 18 prevent the collar 64 from sliding along the exterior surface of the drive tube 66 in the axial direction 18. Four socket head cap screws 70 extend through the collar 64 and into the drive tube 66 but do not extend to the drive shaft 80 or into the first and second drive side inserts 82, 88. The socket head cap screws 70 prevent rotation of the collar 64 relative to the drive tube 66 in the circumferential direction 20. In this regard, the socket head cap screws 70 prevent the collar 64 from spinning relative to the drive tube 66 onto which the collar 64 is mounted.

[0031] The engagement zone 16 is located completely on the collar 64 and features a pair of ears 54, 56 that mark the terminal ends 46, 48 of the engagement zone 16. With reference to Fig. 5, the collar 64 is made of two pieces with each one extending 180 degrees about the drive tube 66 in the circumferential direction 20. The line running along the center of the collar 64 in Fig. 5 in the axial direction 18 is the meeting point on one side between the two halves of the collar 64. With reference Figs. 4-7, the collar 64 has a first hose clamp recess 72 and a second hose clamp recess 74 on either side of the engagement zone 16 in the axial direction 18. The engagement zone 16 is not located at either the first hose clamp recess 72 or at the second hose clamp recess 74. The recesses 72, 74 extend completely around the collar 64 in the

circumferential direction 20, and the socket head cap screws 70 are located in the recesses 72, 74 and extend through the collar 64 at these locations. A first hose clamp 76 is shown in Fig. 5 and is located in the first hose clamp recess 72 and squeezes the collar 64 at this location to cause the collar 64 to be attached to the drive tube 66 to prevent it from falling off of the drive tube 66. A second hose clamp 78 also shown in Fig. 5 is located within the second hose clamp recess 74 and functions to hold the collar 64 onto the drive tube 66 at this point to likewise aid in preventing the collar 64 from detaching from the drive tube 66. The hose clamps 76, 78 are not shown in Figs. 4, 6, 7 for purposes of clarity. The hose clamps 76, 78 along with the socket head cap screws 70 can be applied and disengaged by the user to attach and remove the collar 64 to and from the drive tube 66 as desired in order to render the collar 64 releasably attachable to the drive tube 66. The outer surface 14 is thus made up of both the outer surface of the collar 64 and a portion of the outer surface of the drive tube 66. The collar 64 may be made from 6061 aluminum, and the shape of the outer surface 14 of the collar 64 may be imparted using a CNC lathe to achieve the desired diameter 36.

[0032] The support roller 10 causes the underside surface 24 to be built up at necessary locations so that it presents an even surface to the adhesive application roller 94 for the even spreading of adhesive 26 onto the underside surface 24. A more consistent adhesive 26 application is performed at the adhesive application stage, and the retread band 12 will be better adhered to the carcass when manufacturing a retread tire. The use of a support roller 10 with a known positioning of the engagement zone 16 may result in a more uniformly constructed retread tire as the retread band 12 will be supported in a consistent and known manner. By leaving the engagement zone 16 at the at least one groove 28 not profiled with the shape and size of the at least one groove 28, while profiling the rest of the engagement zone 16, Applicants have unexpectedly discovered that the resulting adhesive 26 application is evenly spread over the surface of the underside surface 24 for a uniform and consistent connection between the retread band 12 and the tire carcass.

[0033] While the present invention has been described in connection with certain preferred embodiments, it is to be understood that the subject matter encompassed by way of the present invention is not to be limited to those specific embodiments. On the contrary, it is intended for the subject matter of the invention to include all alternatives, modifications and equivalents as can be included within the spirit and scope of the following claims.