Agricultural or construction-vehicle with air cooled cased power unit - has matching perforated silencing material inside air entry and exit panels

摘要

The agricultural or construction-vehicle, partic. earth mover, has a fully-encased power unit with a fan and/or radiator. The casing is at least partially lined with silencing material and has two or more air entry/exit zones (17,21) with perforated panels. Internally contiguous with each perforated panel is a foam block at least 60 mm thick with cylindrical perforations (41) coinciding with those in the panel. Perforation bore is 30 - 70 mm; pref. 40 - 60, partic. 50. Advantageously block thickness is two to five times perforation bore.