Internal combustion engines are used to power a wide array of “off-road” applications, such as lawn mowers, chainsaws and leaf blowers. Exhaust systems are provided for these engines to guide waste gases away from the engine. These systems typically direct waste gases through one or more inlet tubes to a muffler, which silences the noise of the escaping exhaust gases before they are expelled from one or more outlets. Reduction of the noise generated by the escaping exhaust gases is important in these “off-road” devices because a user of the device is often positioned in close proximity to the engine during operation of the device.
Mufflers known in the art generally comprise a number of separately manufactured components including a housing that encloses multiple internal baffles, transfer tubes, and/or expansion chambers. These known exhaust systems are expensive to manufacture due to the complexity of the systems and particularly the complexity of the muffler. This expense is further increased since exhaust systems are typically tailored for individual off-road engine designs, which vary considerably between applications and manufacturers. Consequently, for many off-road applications the exhaust system may account for a large portion of the total manufacturing expense.
Additionally, while known exhaust systems are somewhat successful in muffling the noise of the escaping exhaust gases, there is always a need and desire to improve the sound attenuation capabilities of a muffler and exhaust system.
Thus, there is a need in the art for an improved exhaust system and muffler that alleviates one or more of the deficiencies of the prior art discussed above by providing reduced assembly complexity and/or improved sound attenuation. Providing a muffler that is suitable for more than one application or engine design is also desired.