| 摘要 |
<p>A jet propelled boat (10) whose propulsion unit is very compact vertically and in which entrance of the water into the exhaust system is effectively prevented. The jet propulsion unit includes an engine (42) having a vertical output shaft (83), an impeller housing (44) secured to the engine beneath the same and housing an impeller (76) driven by the engine and an exhaust gas housing (43) surrounding the impeller housing having the walls thereof spaced from the impeller housing (44) sufficiently to form a gas chamber, this exhaust gas housing being connected to the exhaust gas discharge (34) below the normal water line and also to the exhaust manifold. The propulsion unit may be used either in connection with an inboard engine or with an outboard engine. In either case, provision is made for changing the direction of the boat and for reversing the same. In the case of the outboard engine, I provide a novel arrangement for combining in one housing below the propulsion unit, an inlet (104) for admitting water to the impeller, a chamber (43) for exhausting the exhaust gas quietly and an elbow (135) for reversing the flow of water issuing from the jet nozzle when it is desired to reverse the boat. In the inboard form of the invention, a swival connection (352) is provided for reversing the discharge nozzle (351) to reverse the direction of the boat, this arrangement discharges the water immediately below the boat without the nozzle extending below the boat. </p> |
