| 摘要 |
An internal combustion engine cold start device has an air valve which co-operates with a valve seat to vary the cross-sectional area of an auxiliary air supply passage upstream of a plug valve in the passage. The air valve is urged towards the valve seat by coil spring. A fuel metering orifice communicates with the passage between the two valves. The plug valve has a profiled valve member which is linked to a profiled needle which projects into the fuel metering orifice, the needle and the plug valve member being guided for rectilinear movement together along parallel paths to respectively throttle the passage and vary the area of the metering orifice. A coil spring opposes rectilinear movement of the plug valve member and the needle to reduce flow through the passage and the orifice respectivey. A thermostatically controlled movable stop co-operates with the linkage which links the plug valve member and the needle so as to limit the permitted movement of the plug valve member and the needle together against the action of the coil spring and to increase that permitted movement as the temperature of the engine increases. In one embodiment the air valve and the plug valve are coaxial, the air valve being annular and being guided by a rod which carries the plug valve member. In another embodiment the air valve is carried by a plunger which slides in a through bore in the body of the device, the through bore being parallel to the plug valve path and communicating with the passage downstream of the plug valve. |
