Fuel Enrichment Starting Device for Carburetor Low-Temperature Reliability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current engine starting methods using choke devices are cumbersome, difficult to operate, and often fail to start engines at low temperatures due to the complexity of achieving the required air-fuel ratio.
Innovation Solution
A fuel enrichment simple starting device for carburetors, featuring a main body with a fuel cup, fuel pumping chamber, fuel enrichment chamber, and specific passages and valves, generates positive and negative pressures to inject fuel into the mixing room, increasing the air-fuel ratio and simplifying the starting process.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a choke device is used to reduce air amount and achieve high air-fuel ratio, then the engine can start at higher temperatures, but the starting process becomes cumbersome and complex
Solution Approach 1:
The patent extracts the fuel enrichment function from the complex choke device and concentrates it into a simple fuel cup mechanism. The fuel cup directly delivers enriched fuel mixture to the carburetor without requiring multiple manual operations (squeezing purge bulb, closing choke, opening throttle, etc.), thereby simplifying the starting process while maintaining reliable engine starting capability.
Solution Approach 2:
The fuel cup pre-mixes and stores enriched fuel mixture before the starting process. By preparing the fuel enrichment in advance within the fuel cup, the system eliminates the need for complex real-time fuel adjustment operations during starting, reducing procedural complexity while ensuring reliable engine initiation.
2Reliability
If a choke device is used to control air-fuel ratio, then the engine can start under normal conditions, but it becomes difficult to judge the POP sound and start the engine
Solution Approach 1:
The fuel cup mechanism automatically provides the correct air-fuel ratio enrichment without requiring the operator to monitor or detect POP sounds. The system self-regulates fuel delivery based on the fuel cup's internal mechanism, eliminating the need for operator judgment and simplifying the starting operation to a simple activation.
3Reliability
If a choke device is used for starting, then the engine can start under normal temperatures, but the engine is difficult to or cannot start at low temperatures (such as 0 degree centigrade)
Solution Approach 1:
The fuel cup changes the fuel delivery parameters by providing a higher concentration of fuel and adjusted air-fuel ratio specifically for cold starting conditions. This parameter modification enables the engine to start reliably at low temperatures (0°C and below) where the conventional choke device fails, significantly improving temperature adaptability.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The device simplifies engine starting by increasing the air-fuel ratio, making it easier to start engines at low temperatures with fewer attempts, thereby improving efficiency.
Implementation Method 1
A positive pressure generated by pressing the fuel cup is transmitted to the fuel pumping chamber through the pump transferring passage to drive the fuel pump diaphragm to vibrate
Implementation Method 2
A positive pressure generated by pressing the fuel cup is transmitted to the fuel pumping chamber through the pump transferring passage
Implementation Method 3
a duckbill valve is disposed in the fuel returning passage, the fuel passage and the fuel returning passage are separated by the duckbill valve
Implementation Method 4
a first retaining valve is located in the fuel inputting passage and configured to prevent fuel in the fuel enrichment chamber from returning to the metering room
Implementation Method 5
a second retaining valve is located in the starting passage and configured to prevent fuel and air in the mixing room from returning to the fuel enrichment chamber
Data Source
AI summary
A fuel enrichment simple starting device for a carburetor includes a fuel cup and a main body, which includes a mixing room, a metering room, a fuel chamber separated into a fuel pumping chamber and a fuel enrichment chamber, a fuel inputting passage, a fuel passage, a starting passage and a fuel returning passage. The fuel pumping chamber and the fuel enrichment chamber are in communication with the fuel cup. One end of the fuel inputting passage is in communication with the fuel enrichment chamber, and the other end thereof is in communication with the metering room. One end of the starting passage is in communication with the fuel enrichment chamber, and the other end thereof is in communication with the mixing room. One end of the fuel returning passage is in communication with the fuel cup, and the other end thereof is in communication with a fuel tank.