| 摘要 |
PURPOSE:To supply an optimum fuel, by introducing a change-over pressure between the pressure upstream of a choke valve and the vacuum just upstream of a fully closed throttle valve into an air chamber in a start fuel diaphragm valve type carburettor through a chage-over valve associated with the choke valve, and by introducing the pressure downstream of the throttle valve into an air chamber in a normal fuel diaphragm type carburettor. CONSTITUTION:Upon start of an engine a change-over valve takes a position as shown in the drawing when a choke valve 8 is closed, the pressure 68 upstream of the choke valve 8 being introduced into a pipe 69 for an air chamber 212 in a gasoline supply diaphragm type carburettor 2, and therefore, gasoline may be fed. The vacuum 65 downstream of a throttle valve 9 is introduced into a pipe 66 for an air chamber 213 in a kerosine supply diaphragm type carburettor 3, and therefore, the supply of kerosine is cut-off. When the choke valve 8 is opened, the vacuum in a hole 67 is greatly changed in accordance with the opening degree of the throttle valve 9 so that the vacuum is introduced into the chamber 212 in accordance with the increase of the opening degree so that the supply of gasoline is cut off. However the pressure in holes 67, 65 come to be near to the atmospheric pressure upon high load operation so that it becomes a condition resembling that upon start of the engine. |
