Method and apparatus for building and transferring a tread belt structure

Abstract

The method of building and transferring a tread belt structure on a portable and collapsible building drum 10 mounted coaxially on a building machine 100 with a rotatable shaft 120 is disclosed. The method includes the steps of forming the annular tread belt 4 on the building drum 10, transferring the building drum 10 with the tread belt 4 from the rotatable shaft 120 onto a pivoting transfer device 200, pivoting the transfer device 200 about 90° rendering the tread belt 4 and axis of the building drum 10 perpendicular to a horizontal plane, collapsing the building drum 10, separating the annular tread belt 4 from the building drum 10, removing the tread belt 4, expanding the tire building drum 10, pivoting the building drum 10 into coaxial alignment with the rotatable shaft 120, moving the building drum 10 onto the shaft 120. The tread belt 4 has one or more elastomeric components applied while hot and the equipment provides means for weighing the tread belt 4.

Description

FIELD OF THE INVENTION [0001] The invention relates to a method and apparatus for building and transferring a large tread belt reinforcing structure on a building drum to a tread belt curing mold. BACKGROUND OF THE INVENTION [0002] The manufacture of annular tread belts for later assembly to an unvulcanized tire carcass is known. [0003] One method described in U.S. Pat. No. 3,865,670 taught the use of an expansible and contractible transfer ring for conveying a breaker tread assembly from a building drum in a tire building machine to a tire carcass mounted on a tire shaping machine. [0004] An improved but somewhat similar U.S. Pat. No. 3,888,720 also disclosed a separate tread breaker building drum designed to vary in size to accommodate different sizes of tires. [0005] Similarly, the Charles E. Todd patent U.S. Pat. No. 3,865,669 also disclosed an expansible and contractible transfer ring for conveying a breaker-tread assembly. [0006] Each of these prior art patents recognized that...

AI Technical Summary

Benefits of technology

[0018] Preferably, the steps of forming the elastomeric layers are accomplished by calendering or extruding strips or sheets of unvulcanized rubber at the tread belt building machine. The steps of controlling the weight of the elastomeric material is accomplished by adjusting the gauge of the material as a function of the monitored weight of the building drum or by increasing the number of windings of the unvulcanized rubber by an increased rotation of the building drum.

Problems solved by technology

While these assembly techniques provided efficiencies in production, none really changed the method for actually forming a tire assembly.

These non-uniformities can lead to mass imbalance issues, irregular wear and a variety of associated ride and handling performance issues.

In the manufacture of very large tires the curing cycle my take many hours.

The size of these tires is extremely large.

Slight variations in the manufacturing process can be very costly.

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