JPS58113565A - Air-fuel ratio regulator for carburetor - Google Patents

Abstract

PURPOSE:To control the air-fuel ratio properly by utilizing the cooling water for an engine to regulate the air in the pilot system of a carburetor. CONSTITUTION:A pilot air path 6 is provided at one side of main air path 1 while a retreatable throttle valve 8 is projected at the intermediate section of said path 6. Upon warming of an engine, the cooling water pressure will increase to push a plunger 15 thus to push down said valve 8 against a spring 11 thereby said path 6 will open to increase the air flow. Consequently the fuel to be fed through a pilot path 5 can be diluted. In such a manner the air-fuel ratio can be corrected in the proper direction in accordance to the engine temperature and the engine rotation.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an air-fuel ratio control device for a carburetor for an internal combustion engine.

The carburetor used in the small engine of a motorcycle is made with a small wrinkle, and the air passage is only the main passage. Air-fuel ratio cannot be adjusted by rotation speed. Therefore, the fuel may become thin at low speeds or thicken at high speeds, making it difficult to set up. Further, since the engine cannot be adjusted when it is cold, it takes time to warm up and demodulate.

This invention takes #1 consideration to this point, and uses the cooling water that cools the engine to adjust the air in the carburetor's soot system to maintain an appropriate air-fuel ratio of 4C14. Embodiments of the present invention shown in the drawings will be described below.

The carburetor opens and closes a main air passage 1 with a piston-type throttle valve 2 that slides up and down. The main air passage 1 is designed to allow fuel to flow from the main fuel passage 3, and as the throttle valve 2 slides up and down, a nine-needle valve 4 protruding below the throttle valve 2 controls the flow of fuel. Adjust. On the other hand, a main pilot passage 5 is opened on one side of the main air passage 1, and fuel pressure air from the main pilot air passage 6 and the pilot fuel passage 7 is mixed into the main pilot passage 5. What you do now flows.

Therefore, in the present invention, a storage adjustment valve 8 that moves forward and backward is provided in a protruding manner in the middle of the main air passage 6. The base end of the throttle flange valve 8 is connected to a plunger 10K of a plunger chamber 9. 11 is a spring. On the other hand, the cooling water pump of the discharge pipe 13 of the cooling water pump 7'12, which is linked to the engine and circulates the engine cooling water between the radiator and the engine! A plunger chamber 14' having one end open to the discharge pipe 13 is provided at a position close to the plunger chamber 14, and a free plunger 15 is slidably inserted into the plunger chamber 14. Then, the plunger chamber 9 and the plunger chamber 14 were
The total amount of air flowing into the main air passage 6 communicated with can be adjusted by an air crease 17 at the inlet.

Next, its effect will be explained.

Inside the coolant discharge pipe 13, as the rotation of the coolant pore 7'12, which rotates with the rotation of the engine, increases, the one-path resistance increases and the pressure rises. Also, since the cooling water is sealed within a certain volume of the engine and radiator, as the engine warms up from a cold state, the pressure increases. When the pressure increases, the plunger 15 is pushed down against the throttle control valve 8 and the spring 11.
・Open the air passage 6 of the 9th pilot to increase the air flow.

Therefore, it is possible to reduce the amount of fuel coming out of the main pilot passage 5. In this way, the air-fuel ratio can be corrected in an appropriate direction depending on the engine temperature and engine speed. still.

Depending on the setting of the engine, it is also possible to reverse the direction of the plunger chamber 9 so that the throttle control valve protrudes as one revolution increases.

As explained above, the present invention provides a throttle control valve gold plate that moves forward and backward into the main air passage of a carburetor, and
Since the i1 control valve is moved forward and backward according to the pressure in the discharge pipe of the cooling water pump linked to the engine, the throttle control valve is moved forward and backward depending on the pressure change in the discharge pipe depending on the rotation speed and engine temperature, and the amount of air is adjusted. By varying the air-fuel ratio, the air-fuel ratio can be corrected in an appropriate direction. This provides advantages such as easier setting of the carburetor and lower fuel consumption.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention L2, FIG. 1 is a longitudinal cross-sectional view, and FIG. 2 is an enlarged cross-sectional view of the throttle control valve portion. 6... Neulot air passage, 8... Throttle control valve. 12...Cooling water pump, 13...Discharge pipe. Applicant's representative Aki Mata I/f51 1. 2-Prisoner

Claims (1)

[Claims] A throttle control valve that moves forward and backward in the air passageway of the carburetor, and is pressurized to move forward and backward in accordance with the pressure within the discharge pipe of a cooling water ponder that is linked to the engine. t-Characteristic air-fuel ratio adjustment device for a carburetor.