Air cooled IC engine - has sound absorbing cover clamped tight to cooling ribs to dampen vibration

摘要

The engine cylinder (1) and head (2) have cooling ribs (3) projecting from them. A sound absorbing enclosure covers the sides and top of the cylinder and head allowing cooling air to flow from front to back. The enclosure consists of a three sided cover (6) which is sufficiently rigid to be self supporting and which is lined internally with a foamed sound absorbing material (7). It has a flange (16) at the bottom which is bolted to the lowest cooling rib. The width of the cover is such that it is forced against the ribs under tension. This provides damping which reduces vibration of the ribs.