A process for building tyres for vehicle wheels includes: forming a tyre in process, the tyre including a belt structure and depositing a tread band in a position radially external to the belt structure by winding a continuous elongated element made of elastomeric material according to axially adjacent or partially overlapped coils. During the deposition of the tread band and on at least one of the coils already wound, a conductive liquid elastomeric compound is applied, the compound continuously extended between a radially outer surface of the tread band and a radially outer surface of the belt structure to generate electrically conductive paths and free zones.

A continuous elongated element of elastomeric material is produced through an extruder at a linear delivery speed and directly fed onto a moving surface of a conveyor without interposition of other devices. The continuous elongated element is advanced on the moving surface along a predetermined direction and at a linear advancing speed different from the linear delivery speed until a proximal end of the conveyor. Subsequently, the continuous elongated element is applied onto a forming support which rotates relative to the proximal end of the conveyor at a peripheral speed different from the linear delivery speed, so as to deform the continuous elongated element and apply it in the form of wound coils onto the forming support in order to form a component of elastomeric material of a tyre.

A continuous elongated element of elastomeric material is produced through an extruder at a linear delivery speed and directly fed onto a moving surface of a conveyor without interposition of other devices. The continuous elongated element is advanced on the moving surface along a predetermined direction and at a linear advancing speed different from the linear delivery speed until a proximal end of the conveyor. Subsequently, the continuous elongated element is applied onto a forming support which rotates relative to the proximal end of the conveyor at a peripheral speed different from the linear delivery speed, so as to deform the continuous elongated element and apply it in the form of wound coils onto the forming support in order to form a component of elastomeric material of a tyre.

In a tire, a tread rubber includes a first layer which is grounded on a road surface in an outer peripheral surface thereof, and a second layer which is joined to an inner peripheral surface of the first layer in an outer peripheral surface thereof, the first layer includes a joint portion where rubbers having different elastic modulus are joined, and the second layer is formed by a rubber having a greater elastic modulus than an elastic modulus of at least one of the rubbers constructing the first layer.

In a tire, a tread rubber includes a first layer which is grounded on a road surface in an outer peripheral surface thereof, and a second layer which is joined to an inner peripheral surface of the first layer in an outer peripheral surface thereof, the first layer includes a joint portion where rubbers having different elastic modulus are joined, and the second layer is formed by a rubber having a greater elastic modulus than an elastic modulus of at least one of the rubbers constructing the first layer.

A system for making a tire tread includes an extruder, a roller die having a first axis of rotation, and a conveyor that receives a round strip (or noodle) of green rubber from the extruder and feeds the strip of green rubber to the roller die. The system further includes a drum having a second axis of rotation, wherein the roller die is configured to apply the strip of green rubber to the drum. The system also includes a controller, wherein the controller is configured to control a translation of the roller die in a first direction parallel to the first axis of rotation. The controller is configured to control a roller die rotation speed and a drum rotation speed, and the controller varies at least one of the roller die rotation speed and the drum rotation speed during translation of the roller die.

A system for making a tire tread includes an extruder, a roller die having a first axis of rotation, and a conveyor that receives a round strip (or noodle) of green rubber from the extruder and feeds the strip of green rubber to the roller die. The system further includes a drum having a second axis of rotation, wherein the roller die is configured to apply the strip of green rubber to the drum. The system also includes a controller, wherein the controller is configured to control a translation of the roller die in a first direction parallel to the first axis of rotation. The controller is configured to control a roller die rotation speed and a drum rotation speed, and the controller varies at least one of the roller die rotation speed and the drum rotation speed during translation of the roller die.

Disclosed are pneumatic vehicle tires and methods of their production, the tires comprising a tread that has a tread segment arranged radially on the outside, and a material strip that is arranged helically in windings approximately in the circumferential direction, wherein, in the region of the tread segment, the material strip has at least two layers in the longitudinal direction of the material strip, wherein the first layer is formed from a first rubber compound and the second layer is formed from a second rubber compound, and wherein the layers connect the radially outer surface to the radially inner surface of the tread segment. The disclosed pneumatic vehicle tire has lower noise emissions and more uniform wear during driving and is improved in respect of at least one conflict of aims.

Disclosed are pneumatic vehicle tires and methods of their production, the tires comprising a tread that has a tread segment arranged radially on the outside, and a material strip that is arranged helically in windings approximately in the circumferential direction, wherein, in the region of the tread segment, the material strip has at least two layers in the longitudinal direction of the material strip, wherein the first layer is formed from a first rubber compound and the second layer is formed from a second rubber compound, and wherein the layers connect the radially outer surface to the radially inner surface of the tread segment. The disclosed pneumatic vehicle tire has lower noise emissions and more uniform wear during driving and is improved in respect of at least one conflict of aims.

A method for forming a composite tread with microchimneys, the method comprising the steps of providing a coextruded strip formed of a first compound and a second compound, wherein the first compound is a tread compound, and the second compound is electrically conductive, and then winding the coextruded strip onto a tire building drum to form a tread.