Catalyst body and an exhaust system for a small-size engine and a method for producing the catalyst body

摘要

The invention relates to a radial-flow annular catalyst body for installation in a muffler housing of a small-size engine, an exhaust system for a small-size engine and a method for producing the catalyst body. The catalyst body consists of a perforated metal foil. In a preferred embodiment, the perforations of the perforated metal foil are adjusted for sound reduction in such a way that the metal foil simultaneously assumes the function of a conventional reflection body. In a further preferred embodiment of the metal foil forming the catalyst body, webs for stiffening the metal foil are arranged between the perforations, which webs are adapted in such a way that they prevent any bulging of the metal foil in the installed state. In a further preferred embodiment, the ends of the metal foil are joined in a detachable interlocking connection. For producing the catalyst body in accordance with the invention, the catalyst body is bent in an annular way from a perforated metal foil strip. Thereafter the ends of the strip are joined by means of an interlocking connection. In a preferred production method, the perforated metal foil strip is cut, punched or broken from previously applied perforation points from endless merchandise. The production from endless merchandise allows a continuous coating process and especially considerable cost savings. The metal foil which can be adapted for sound reduction as a replacement for a conventional muffler unit also has favorable stability properties in addition to the catalytic effect. A conventional reflection body can be omitted because the perforations can be adapted for sound reduction and pollutant reduction. One component of a conventional exhaust system can thus be omitted.