An engine device including an exhaust gas purification device above cylinder head through a support pedestal. The support pedestal has a flat portion on which the exhaust gas purification device is mounted, and a plurality of legs which protrude downward from the flat portion and are fixed to the cylinder head. The flat portion and the leg portions are formed integrally. Portions between the legs are each formed in an arch-shape.

A heat management system for air-cooled engines suitable to power yard care equipment or vehicles. The system may generally comprise an engine, a blower configured to blow ambient cooling air across the engine, and an exhaust system comprising an exhaust header and a muffler. The exhaust header has an inlet end which receives heated exhaust gas from the engine and an outlet end fluidly coupled to the muffler. An air control baffle is configured to redirect a portion of the cooling air from the blower towards the exhaust header and the muffler to enhance cooling the exhaust system. The system may further include an outermost protective shield exposed to equipment operators and an inner heat barrier or shield located between the muffler and protective shield. The system is designed to ameliorate both radiative and convective sources of heat transfer to maintain the protective shield at temperatures below established industry standards.

A utility vehicle includes an exhaust assembly fluidly coupled to an engine. Depending on various parameters, such as the size and/or performance of the vehicle, the exhaust assembly is required to meet certain emissions regulations. Such emissions regulations may be met by increasing the temperature within the exhaust assembly, however, at particularly high temperatures, a catalyst of the exhaust assembly may be damaged. Therefore, the exhaust assembly includes various options for cooling portions thereof to remove heat from the assembly.

An engine device includes an exhaust gas purification device above a cylinder head through a support pedestal. The support pedestal has a flat portion on which the exhaust gas purification device is mounted, and a plurality of legs which protrude downward form the flat portion and are fixed to the cylinder head. The flat portion and the leg portion are formed integrally. Portions between the legs are each formed in an arch-shape.

A heat management system for air-cooled engines suitable to power yard care equipment or vehicles. The system may generally comprise an engine, a blower configured to blow ambient cooling air across the engine, and an exhaust system comprising an exhaust header and a muffler. The exhaust header has an inlet end which receives heated exhaust gas from the engine and an outlet end fluidly coupled to the muffler. An air control baffle is configured to redirect a portion of the cooling air from the blower towards the exhaust header and the muffler to enhance cooling the exhaust system. The system may further include an outermost protective shield exposed to equipment operators and an inner heat barrier or shield located between the muffler and protective shield. The system is designed to ameliorate both radiative and convective sources of heat transfer to maintain the protective shield at temperatures below established industry standards.

A machine body comprises a sieving frame having a bottom plate. The machine body comprises an engine. The machine body comprises an exhaust gas cleaning apparatus that executes reduction treatment on a predetermined oxide in an exhaust gas of the engine by injecting a liquid reducing agent. The machine body comprises a reducing agent tank that stores a liquid reducing agent. The machine body comprises a reducing agent pump that feeds the liquid reducing agent stored in the reducing agent tank to the exhaust gas cleaning apparatus. The machine body comprises a cooling fan. The machine body is disposed on the bottom plate of the slowing frame and comprises an opening section that takes in outside air that cools the reducing agent pump by driving the cooling fan. The machine body comprises a duct section that leads the outside air taken from the opening section to the cooling fan.

A problem to be solved is to provide an exhaust promotion method, an exhaust promotion device, and an exhaust system improvement method for an internal combustion engine capable of further improving the exhaust efficiency by high-speed exhaust of exhaust gas.

What is characteristic is that an exhaust gas discharged from the internal combustion engine is expanded in multiple stages repeatedly to reduce a temperature thereof, and thus exhaustion is performed while suppressing a behavior derived from a thermal energy of the exhaust gas.

An exhaust assembly includes a first tailpipe having an exit end and a curved portion along at least a portion of a length of the first tailpipe. The exhaust assembly further includes a baffle surrounding the first tailpipe at the exit end and defining a plurality of perforations therethrough. The exhaust assembly further includes a pair of shields. Each shield is attached to and at least partially surrounds each of the baffle and the first tailpipe. Each shield extends from a first end proximal to the exit end of the first tailpipe to a second end distal to the exit end of the first tailpipe. Each shield engages the baffle at the first end and engages the first tailpipe at least at or proximal to the second end. The pair of shields is adapted to allow fluid flow to or from the plurality of perforations of the baffle.

Methods, systems, and vehicles that control the temperature of a device included in the vehicle are presented herein. The temperature of the device is controlled by ventilating the device with drivetrain air, such as transmission cooling air. In some embodiments, the device is at a greater temperature than the drivetrain air, which cools the device. In other embodiments, the device is at a lesser temperature than the drivetrain air, which heats the device. The drivetrain air is provided to the device through an exhaust duct coupled to the vehicle's transmission. The drivetrain exhaust air is preferably circulated by the transmission. The transmission may be a continuously variable transmission. The device may be an oxygen sensor that is coupled to an engine exhaust pipe. The oxygen sensor is thermally coupled to the engine exhaust and the engine exhaust pipe, which are at greater temperatures than the transmission exhaust air.

Engine systems and methods use a dual air injection approach to control exhaust reactions and to maintain temperatures below a maximum limit of exhaust system components during engine enrichment operation conditions. Dual air injectors are disposed in the exhaust system with one upstream from, and another downstream from, the catalytic converter. Providing air injection before and/or after the converter helps convert all HC, CO, and PM emissions while keeping the catalyst temperature below the catalyst protection temperature limit. Air injection quantity may be controlled and diagnosed by monitoring the temperatures before and after the catalytic converter. The catalytic converter may be a three-way catalytic converter for lower cost or a downstream two-way catalytic converter may be added if further emission reduction is necessary.