Snowthrower including power boost system

摘要

A carburetor includes a passageway having a constricted section, a nozzle directed into the passageway proximate the constricted section, and a shaft having a surface that at least partially defines the constricted section. The nozzle is configured to deliver fuel to air passing through the passageway, and the surface includes a contour that is configured to be moved relative to the passageway to change the area of the passageway through the constricted section.

主权项

1. A snow thrower having a power boost mode, the snow thrower comprising:
a frame; wheels coupled to the frame; a fuel tank; an engine mounted to the frame, comprising:
an air intake;a combustion chamber;a passageway configured to channel air from the air intake to the combustion chamber, wherein the passageway comprises a surface at least partially defining a constricted section of the passageway, and wherein the surface is configured to be adjusted to change the area of the passageway through the constricted section;a well configured to hold fuel delivered to the well from the fuel tank; anda nozzle in fluid communication with the well and directed into the passageway proximate to the constricted section of the passageway, whereby the constricted section of the passageway provides a relative low pressure in air passing through the passageway that draws fuel from the nozzle to the air; a rotating tool driven by the engine; and a control interface, wherein manual control of the control interface increases the flow rate of air through the passageway to increase the combustion processes of the engine and provide a power boost mode having greater output for the engine.