| 摘要 |
A pneumatic tyre has a protuberance on one or both walls. Each protruberance has an upper and lower surface connecting at a point C. A line from this point forming a tangent to the edge of the tyre tread makes a first angle ( alpha )≤45 degrees to the t axis. When normally inflated the point C is at least half the distance that the widest part (M) of the tyre wall lies from the equatorial plane. The point C is further from the rotation axis than the widest part. A second angle ( delta )≥60 degrees i defined a tangent (D2) to the bottom of the side edge of the tread and a line from the point C to an imaginary extension of an outermost reinforcement layer to the side edge of the tread. The first angle ( alpha ) may be 32-37 degrees . The protuberance extends radially at least beyond the bottom of the tyre t pattern. The weight of the protuberance is reduced by two series of holes opening in only its upper and lower surfaces respectiv The holes are oriented to prevent liquid moving within them when the tyre is in use. |
