Dynamic damping device for steering system

A dynamic damping device for use in a steering system equipped with a telescopic steering column of an automotive vehicle, and adapted to be mounted on a steering column and/or a steering wheel of the steering system for damping vibrations excited in the steering wheel, the dynamic damping device comprising:

• a plurality of dynamic dampers each including a mass member and a spring member for elastically supporting said mass member with respect to the steering column or the steering wheel, said plurality of dynamic dampers being independent of each other,
• wherein said plurality of dynamic dampers have respective natural frequencies that are arranged such that at least two of said natural frequencies of said plurality of dynamic dampers are tuned respectively to a higher and a lower frequency range in relation to a central value of a range of variation in a natural frequency of the steering wheel due to an expansion or contraction of the telescopic steering column, and held within said range of variation in said natural frequency of the steering wheel, and such that differences between adjacent ones of said natural frequencies of said plurality of dynamic dampers are held within 10-40% of said central value of said range of variation in said natural frequency of the steering wheel,
• wherein said natural frequencies of said plurality of dynamic dampers are all held within said range of vibration in said natural frequency of the steering wheel due to said expansion or contraction of the telescopic steering column, and
• wherein said spring member of each of said plurality of dynamic dampers comprises an elastic support member adapted to undergo shear deformation in a direction perpendicular to a central axis of the steering column or the steering wheel.