Fuel supply limiter for carburetor

Abstract

The present invention provides a fuel supply device for a carburetor that has no problem of fuel leakage and has excellent responsiveness due to simple piping. Supply mechanism, low-speed system mixed gas supply mechanism, the low-speed system mixed gas supply mechanism consists of the low-speed air passage sandwiching the low-speed air metering hole and the low-speed fuel passage sandwiching the low-speed metering hole when the throttle opening is fully closed When the opening is small, the mixed gas is supplied to the internal combustion engine, which has a second low-speed air passage (21) and a control valve (23). The upstream side of the connection point of the passage (12) communicates with the downstream side of the low-speed air volume hole (14a), and the control valve (23) is provided in the middle of the second low-speed air passage (21) for opening and closing the passage.

Description

technical field [0001] The invention relates to a fuel supply limiting device for a carburetor of an internal combustion engine. Background technique [0002] When there is a low-speed system mixed gas supply mechanism in addition to the main system mixed gas supply mechanism, when the low-load operation and no-load operation include a small opening including the throttle valve opening fully closed, the low-speed system The mixed gas supply mechanism replaces the main system mixed gas supply mechanism to supply the mixed gas to the carburetor of the internal combustion engine, in order to prevent the unburned mixed gas from being discharged into the exhaust system when the ignition circuit is opened or when decelerating, causing the catalyst of the exhaust purification device to A device for limiting fuel supply is proposed due to melting loss and the like. [0003] In addition to the example in which an electromagnetic on-off valve is interposed in the fuel passage to dire...

AI Technical Summary

Problems solved by technology

[0018] It is difficult to ensure the tightness of the fuel by installing an electromagnetic on-off valve in the fuel passage to directly limit the fuel supply (Japanese Patent No. 2860084). Fuel leakage may occur due to the use of the on-off valve in a wet environment.

[0019] In addition, in Figure 7 In the case of the example shown (Japanese Unexamined Patent Publication No. 59-229040), the piping is numerous and complicated, assembling is troublesome, and space utilization is not good.

[0020] In addition, due to the length and volume of the piping that introduces the negative pressure, the pressure fluctuation of the float chamber 04 is delayed, and the response of fuel supply restriction and release is sluggish.

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