Tire Tread Pattern Noise Reduction Through the Application of Pitch Sequencing

The goal of this paper is to provide an automotive engineer with an explanation of the basic pitch sequencing concepts. It will also provide a historical overview of the various approaches that have been used to develop quiet tires and their progression in effectiveness. Graphs will show a Fourier analysis of the individual pitch sequences used as examples. These examples have been pulled from various US patent documents, since literature on this subject tends to be very sparse.

The reduction of tire noise in the vehicle interior has been a major field of research in the tire industry for many years. Pitch sequencing for tire tread designs has been the primary method for obtaining improvements in subjective tire noise quality for about 60 years. Pitch sequencing is a method of providing frequency modulation in the tire by selectively arranging tread elements of various sizes. One of the early patents, awarded in 1950, that has been frequently quoted was by Frederick E. Buddenhagen of the Armstrong Rubber Company. This patent provides a very good example of an early pitch sequence.

Pitch sequences have been very effective through the years in providing the automotive industry with tires that help meet the ever more stringent demands on noise quality. It is the hope of the author that this paper will help explain what is required to provide these noise improvements.