1. Field of the Invention
The invention relates to a method for producing a pneumatic tire for a vehicle, with a casing which extends over the circumference of the pneumatic vehicle tire, with a belt which extends radially outside the casing over the entire circumference of the pneumatic vehicle tire and in the axial direction at least over the tread contact width of the pneumatic vehicle tire. The belt comprises one or more belt plies with reinforcing elements in each case formed obliquely in relation to the circumferential direction of the tire and embedded in parallel in unvulcanized or vulcanized rubber. A bandage extends radially outside a belt ply of the belt over the circumference of the pneumatic vehicle tire, wherein, on the belt ply—in particular the radially outer belt ply—of the belt built up on a rotatable rotationally symmetrical building body, one or more parallel reinforcing elements, aligned substantially in the circumferential direction, is or are wound helically or spirally in the axial direction of the building body around the belt ply—in particular the radially outer belt ply—built up on the building body to produce the bandage.
It is known, for limiting undesired radial dimensional changes of the belt caused by high centrifugal forces acting on the belt, to form around the radially outer belt ply of high-speed tires a bandage ply comprising a rubber strip spirally wound continuously over the entire axial extent of the belt, with reinforcing elements embedded therein in the longitudinal direction of the rubber strip. The resultant identical direction of pitch in which the reinforcing elements run over the entire axial extent of the belt of the tire can lead to concentricity problems. In order to reduce these, it is known, for example from European published patent application EP 0 712 739 A1, to form the bandage symmetrically in relation to the equatorial plane of the tire, in that a first bandage strip is wound on by a first winding head from one edge of the belt and a second bandage strip is wound on by a second winding head from the second edge of the belt toward the equatorial plane. For this purpose, the winding heads are mechanically coupled to each other in their movement on a common spindle in such a way that the winding operation is performed simultaneously in mirror image on both sides of the equatorial plane. A second ply of the bandage is also produced in the same way, by the bandage strips respectively being spirally wound on by the two mechanically intercoupled winding heads respectively on one axial side of the belt in mirror image in relation to the bandage strip of the other side of the belt.
If part of the bandage is to be made of different bandage material, the corresponding winding head must be converted, in that the material is removed from the winding head, the feeding and aligning regions, and replaced by new material. The symmetrical winding with the two winding heads mechanically coupled by means of the common spindle only makes it possible to obtain for the two winding heads a respectively predetermined axial advancement of the winding heads in relation to each other, and consequently a fixed predetermined ratio of the pitches of the bandage regions respectively wound by the two winding heads and a fixed predetermined ratio of the winding density. In some cases, it is desirable to form individual regions of the bandage with a strip width that is different from the bandage material and/or with a bandage material that is different. If a different strip width is chosen, it is first necessary during the building process for the corresponding winding head and the material feed to be converted to provide reliable guidance of the new strip material. In order that the strips can be laid with the same covering density, the spindle must be exchanged during the building process. Since this means that productive manufacture of such tires is only possible with very great additional effort—if at all—the construction of such tires is usually restricted just to the adaptations that can be achieved with little effort with the two winding heads.
Consequently, although the symmetrical winding on by the two winding heads mechanically coupled by means of a common spindle makes it possible to reduce concentricity problems, this entails considerable restrictions in the formation of the bandage with regard to adaptation to the individual requirements of a tire. In spite of the additional effort, formation of the bandage to correspond to individual requirements for the tire is only possible to a greatly restricted extent.
It is accordingly an object of the invention to provide a method of producing a pneumatic tire for a vehicle which overcomes the above-mentioned disadvantages of the heretofore-known devices and methods of this general type and which makes it possible to better adapt a pneumatic vehicle tire with a belt and a bandage to the individual requirements of a pneumatic vehicle tire.
With the foregoing and other objects in view there is provided, in accordance with the invention, a method of producing a pneumatic vehicle tire, the pneumatic vehicle tire having a casing that extends over a circumference thereof, a belt that extends radially outside the casing over the entire circumference of the pneumatic vehicle tire and, in an axial direction, at least over a tread contact width of the pneumatic vehicle tire, the belt including one or more belt plies with reinforcing elements in each case formed obliquely to the circumferential direction of the tire and embedded in parallel in unvulcanized or vulcanized rubber material, and and pneumatic vehicle tire further having a bandage that extends radially outside a belt ply of the belt over the circumference of the pneumatic vehicle tire. The novel method comprises the following steps:
providing bandage strip building material formed of reinforcing elements in filament form and/or strip-shaped bands each with one or more parallel reinforcing elements;
guiding the bandage strip building material to a rotatable, rotationally symmetrical building body by at least four feeding devices, wherein the feeding devices are disposed for changing a position thereof relative to the building body in a controlled manner; and
helically or spirally winding the bandage strip building material onto a belt ply of the belt built up on the building body by controlled turning of the building body and controlled axial movement of the relative position between the building body and the feeding devices for the winding operation, to thereby build the bandage of the pneumatic vehicle tire.
In other words, the objects are achieved according to the invention by the method for producing a pneumatic tire for a vehicle, with a casing which extends over the circumference of the pneumatic vehicle tire, with a belt which extends radially outside the casing over the entire circumference of the pneumatic vehicle tire and in the axial direction at least over the tread contact width of the pneumatic vehicle tire, said belt comprising one or more belt plies with reinforcing elements in each case formed obliquely in relation to the circumferential direction of the tire and embedded in parallel in unvulcanized or vulcanized rubber, and with a bandage which extends radially outside a belt ply of the belt over the circumference of the pneumatic vehicle tire, wherein, on the belt ply—in particular the radially outer belt ply—of the belt built up on a rotatable rotationally symmetrical building body, one or more parallel reinforcing elements, aligned substantially in the circumferential direction, is or are wound helically or spirally in the axial direction of the building body around the belt ply—in particular the radially outer belt ply—built up on the building body to produce the bandage, according to the features of claim 1, in which bandage strip building material comprising reinforcing elements in filament form and/or strips in band form with in each case one or more parallel reinforcing elements are guided to the building body by at least four feeding devices, which can be changed in a controlled manner with regard to their relative position in relation to the building body, and are helically or spirally wound around the belt ply—in particular the radially outer belt ply—by controlled turning of the building body and controlled axial changing of the relative position between the building body and the feeding devices for the winding onto the belt ply—in particular the radially outer belt ply—of the belt. This makes it possible to obtain not only symmetrical winding of the bandage with regard to the winding direction but also the use of different materials of the reinforcing elements, different widths of the strips in band form and winding angles in relation to the circumferential direction for different belt regions to correspond to the individual requirements of the tire. Even though good concentricity properties are ensured, individual belt regions can be formed very individually with a bandage individually made to match, and other belt regions with a different bandage individually made to match, without requiring any particular conversion effort. As a result, modifications to match specifically loaded belt regions or to match different tread rubber materials used over the axial extent are individually possible.
Other features which are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in method for producing a pneumatic tire for a vehicle, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.
Referring now to the figures of the drawing in detail and first, particularly, to
In the exemplary embodiment, the belt 3 comprises two belt plies with reinforcing elements, in particular of steel cord, running parallel in each ply and embedded in rubber, the reinforcing elements in the two neighboring plies crossing one another. In the tire, the belt plies are arranged in such a way that the steel cords running parallel to one another form an acute angle with the circumferential direction of the tire of the order of magnitude of 15° to 30°, in particular of 20° to 25°. As revealed by
In the finished, vulcanized pneumatic vehicle tire, the bandage strip and the reinforcing element or elements embedded in the bandage strip 11 form a very small angle with the circumferential direction of the tire, when it is in its operating state on the vehicle, of the order of magnitude of 0° to 5°, in particular of 1° to 3°.
For supplying bandage strip building material, each winding head 13, 14, 15, 16 is assigned a material source, for example a storage roller 17 or 18 or 19 or 20, respectively, of a known type, which is rotatably mounted in a housing in a known way. So, for example, bandage strip building materials 21, 22, 23, 24 in band form or cord form are stored on the storage drums 17, 18, 19, 20. The bandage strip building material 21 of the storage drum 17 is laid by the winding head 13. The bandage strip building material 22 of the storage drum 18 is laid by the winding head 14. The bandage strip building material 23 of the storage drum 19 is laid by the winding head 15 and the bandage strip building material 24 of the storage roller 20 is laid by the winding head 16. In one configuration, the bandage strip building materials 21, 22, 23 and 24 are respectively formed in the same way. In another configuration, the bandage strip building materials 21, 22 and 23 are respectively formed in the same way. The bandage building material 24 is differently formed. In a further configuration, the bandage strip building materials 21 and 22 are respectively formed in the same way and the bandage strip building materials 23 and 24 are likewise formed in the same way, but differently from the bandage strip building materials 21 and 22. In another configuration, the bandage strip building materials 21 and 22 are respectively formed in the same way and the bandage strip building materials 23 and 24 are respectively formed differently from each other and also differently from the bandage strip building materials 21 and 22. In a further configuration, all four bandage strip building materials 21, 22, 23 and 24 are differently formed.
In a first configuration, the differences between the bandage strip building materials lie in the choice of the modulus of elasticity and/or in the use of different materials of the reinforcing elements. Possible materials of the reinforcing elements are monofilaments and cords of nylon—in particular nylon 6.6—, rayon, polyester, steel or hybrid cords—for example of aramid and nylon—in particular nylon 6.6—or of steel and nylon—in particular nylon 6.6—as well as all other materials known for use as bandage material. So, for example, some of the winding heads 13, 14, 15 and 16 lay bandage strip building material with heat-shrinkable textile reinforcing elements—for example of nylon 6.6—embedded in the bandage strip building material and some others of the winding heads 13, 14, 15 and 16 lay bandage strip building material with hybrid material of nylon 6.6 and aramid of a known type as reinforcing elements embedded in the bandage strip building material. In another configuration, some of the winding heads 13, 14, 15 and 16 lay bandage strip building material with polyester as reinforcing elements embedded in the bandage strip building material and some others of the winding heads 13, 14, 15 and 16 lay bandage strip building material with hybrid material of nylon 6.6 and aramid of a known type as reinforcing elements embedded in the bandage strip building material. In another configuration, some of the winding heads 13, 14, 15 and 16 lay bandage strip building material with nylon 6.6 as reinforcing elements embedded in the bandage building material and some others of the winding heads 13, 14, 15 and 16 lay bandage strip building material with steel cords as reinforcing elements embedded in the bandage strip building material.
In another configuration, the differences of the conveyed bandage strip building material lie in the width of the conveyed bandage strip building material. So, in one configuration, some of the winding heads 13, 14, 15 and 16 lay bandage strip building material of pure rubberized individual cords and some others of the winding heads 13, 14, 15 and 16 lay unvulcanized rubber bands with a number of parallel reinforcing elements embedded in unvulcanized rubber material. In another configuration, some of the winding heads 13, 14, 15 and 16 lay narrow unvulcanized rubber bands with a number of parallel reinforcing elements, for example three, and some others of the winding heads 13, 14, 15 and 16 lay wider unvulcanized rubber bands with, for example, five, eight or ten parallel reinforcing elements.
In another configuration, the differences of the conveyed bandage strip building material lie in the chosen tensile stress that the wound-on bandage strip material has. These stresses are achieved, for example, by the bandage strip building material being laid with different tensile stress. So, in one configuration, some of the winding heads 13, 14, 15 and 16 lay bandage strip building material with a first, constant, lower tensile stress and some others of the winding heads 13, 14, 15 and 16 lay bandage strip building material with a second, constant, higher tensile stress. In another configuration, some of the winding heads 13, 14, 15 and 16 lay bandage strip building material with a first predetermined tensile stress variation, changed over the axial extent of the winding-on region, and some others of the winding heads 13, 14, 15 are 16 lay bandage strip building material with a second predetermined tensile stress variation, changed over the axial extent of the winding-on region. The tensile stress is in this case controlled or regulated in a known way by the control unit 25 by means of a known force regulating mechanism interacting with the respective winding head.
In a further configuration, the winding heads 13, 14, 15 and 16 lay bandage building material that differs both in the material of the reinforcing elements and in the strip width of the bandage building material. In a further configuration, the winding heads 13, 14, 15 and 16 lay bandage building material that differs both in the material of the reinforcing elements and in the tensile stress of the bandage building material. In a further configuration, the winding heads 13, 14, 15 and 16 lay bandage building material that differs both in the tensile stress of the bandage strip building material and in the strip width of the bandage building material. In a further configuration, the winding heads 13, 14, 15 and 16 lay bandage building material that differs both in the material of the reinforcing elements and in the strip width of the bandage building material, and additionally in the tensile stress of the bandage strip building material.
With the building drum 12 driven in a rotating manner and in dependence on the desired winding patterns for the tire to be produced and different bandage regions to be bandaged, the bandage strip 11 is built up on the belt 3 that has been built up on the building drum 12 in a known way and extends over the circumference of the building drum by the winding heads 13, 14, 15, 16 first being moved in a respectively controlled manner into their working position at the radially outer lateral surface of the building drum and the bandage building material 21, 22, 23, 24 respectively to be laid being guided in each case in a known way by the winding heads 13, 14, 15 and 16, respectively, from the storage rollers 17, 18, 19 and 20, respectively, onto the radially outer surface of the belt 3—for example by laying rollers of a known type that are respectively rotatably mounted on the winding heads but are not represented—and by the bandage strip material 21 or 22 or 23 or 24 that is respectively to be laid by the winding head 13, 14, 15 or 16 being laid with the respectively desired winding pitch in relation to the circumferential direction of the belt by the controlled movement of the respective winding head 13, 14, 15 or 16 performed parallel to the drum axis. The rotational movement of the building drum together with the displacing movement of the respective winding head, performed parallel to the drum axis, produce the spiral or helical winding. As soon as the portion of belt that is to be covered by a winding head 13, 14, 15 or 16 is covered with bandage material, the bandage material is cut off in a known way and the winding head 13, 14, 15 or 16 is moved back in a controlled manner from its working position at the building drum into its rest position away from the latter.
In
In
In the configuration of
The winding pattern of
The third ply may thereby be wound in the same way as the third ply of
In a further configuration—not represented—further additional winding heads—for example two further winding heads—can in the same way be moved in a controlled manner and can be arranged in the region of the building drum in such a way that they can be provided with belt bandage strip material, as illustrated above in connection with the winding heads 15, 16, 17 and 18. In this way it is possible, for example, to produce the winding pattern of
It is similarly conceivable if need be to wind bandage building material onto a belt by eight or twelve winding heads.
The building drum is represented in
| Number | Date | Country | Kind |
|---|---|---|---|
| DE102005018964.4 | Apr 2005 | DE | national |
This is a continuing application, under 35 U.S.C. §120, of copending international application PCT/EP2006/001085, filed Feb. 8, 2006, which designated the United States; this application also claims the priority, under 35 U.S.C. §119, of German patent application DE 10 2005 018 964.4, filed Apr. 23, 2005; the prior applications are herewith incorporated by reference in their entirety.
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/EP2006/001085 | Feb 2006 | US |
| Child | 11865318 | Oct 2007 | US |