TH37541B - Engine with a function for exhaust gas purification - Google Patents

Abstract

The DC60 is equipped with a catalytic converter that incorporates both upstream and downstream catalytic converters housed in the exhaust pipe within a compact muffler. The catalytic converter 20 is connected to the engine and consists of an exhaust pipe inlet 15a, which houses the upstream catalytic converter 21 and the downstream catalytic converter 22, positioned adjacent to the first section, and a muffler 30, which accommodates the exhaust pipe inlet 15a. The muffler 30 is uniquely designed with a first hollow section 32 and a second hollow section with a smaller outer diameter, and the upstream catalytic converter 21 is positioned inside the second hollow section. [Selected drawing] Figure 2 illustrates the catalytic converter that incorporates both upstream and downstream catalytic converters housed in the exhaust pipe within a compact muffler. The exhaust gas purification device 20 is connected to the engine and consists of a section leading to the exhaust pipe end 15a, inside which are the upstream catalytic converter 21 and the downstream catalytic converter 22, positioned at the end next to the first section, and a muffler 30 that supports the exhaust pipe end 15a and is uniquely designed in that the muffler 30 consists of a first hollow section 32 and a second hollow section with a smaller outer diameter than the first, and the upstream catalytic converter 21 is positioned inside the second hollow section. [Selected drawing] Figure 2

Claims (8)

1. The engine is characterized by the following components: an exhaust pipe connected to the exhaust port of an internal combustion engine; an upstream exhaust gas remover positioned in the exhaust pipe; a downstream exhaust gas remover positioned at the end of the upstream remover in the exhaust pipe; a secondary air supply connecting the upstream and downstream removers in the exhaust pipe; and a muffler consisting of a first hollow section with an exhaust pipe inlet opening at the end and a second hollow section connected to the opening and having a smaller outer diameter than the first hollow section. Within this second hollow section, at least a portion of the upstream remover is placed, and the exhaust pipe at the end next to the upstream remover is supported, with the downstream remover located in the first hollow section of the muffler. 2. An engine as specified in Requisition 1, which is made to be of the special type that the engine is a centrifugal engine supported in such a way that it can be thrown from the body of the vehicle. 3. An engine as described in Reservation 1 or 2, which is made to have a special characteristic such that the exhaust pipe, the portion supported in the muffler, is bent after expanding in the longitudinal direction of the muffler. 4. The engine as specified in Reservation 3 is characterized in such a way that the internal combustion engine is arranged in such a way that the cylinder axis of the internal combustion engine is in a near-flat position. 5. An engine as described in Reputation 1 or 2, which is modified so that the muffler contains an inlet flow suppressor that prevents the flow of exhaust gases from entering the second hollow chamber. 6. An engine as described in claim 5, which is characterized in such that an intake flow suppression component is located between the exhaust pipe end supported in the muffler and the exhaust gas exit and a portion of the secondary air intake pipe supported in the muffler. 7. The engine as described in claim 5 is made in such a way that the edge of the current-suppressing assembly is welded to the inner circumferential face of the first hollow body. 8. A straddling vehicle with an engine as specified in Claims 1 or 2.