JPS6321829B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a fuel advance carburetor that can control the fuel via an electronic control circuit, supply a corresponding amount of air, and perform various necessary operations.

In conventional carburetors, the throttle valve opening is first determined by the driver's operation of the accelerator pedal, which changes the air flow rate in the air passage supplied to the engine and changes the negative pressure in the air passage where the main nozzle opens. , the fuel flow rate flowing out from the main nozzle changes in accordance with the negative pressure change. That is, the conventional carburetor is a fuel trailing carburetor.

On the other hand, fuel advance carburetors are usually equipped with an electronic control circuit, and the electronic control circuit sends detection signals indicating engine conditions, atmospheric conditions, etc.
A detection signal indicating the position of the accelerator pedal operated by the driver is sent, and first, a needle valve or the like that controls opening and closing of the fuel inlet of the fuel passage from the float chamber to the fuel nozzle is linked to the accelerator pedal, or the electronic control circuit A command signal from the electronic control circuit controls the opening and closing of the fuel regulating valve via a solenoid and a motor, and at the same time, a command signal from the electronic control circuit controls the opening and closing of the fuel regulating valve.
The throttle valve opening degree is adjusted depending on the fuel flow rate of the fuel nozzle. Therefore, the fuel trailing carburetor is referred to as a fuel leading carburetor.

In other words, the fuel advance electronically controlled carburetor adjusts the fuel flow rate by adjusting the fuel adjustment needle valve in the fuel chamber forward and backward using the accelerator pedal, opens and closes the throttle valve via an electronic circuit, and also controls various engine loads. This system supplies fuel according to the situation, and was filed in a patent application filed in 1982 by the applicant of the present invention.
Proposed as No. 185659.

The fuel advance electronically controlled carburetor according to the above-mentioned prior application is provided with a pressure regulating valve connected to a valve regulator on the upstream side of the main air passage and a throttle valve on the downstream side, and a main air passage formed between these two valves. A fuel nozzle is provided in the constant pressure section of the air passage, the fuel nozzle communicates with the bottom of a float chamber forming a constant pressure oil surface, and a fuel adjustment needle valve that is linked to an accelerator pedal is provided at the fuel inlet. Additionally, an electronic control circuit is provided to control the throttle valve opening according to the fuel flow rate of the fuel nozzle, and the air-fuel ratio is adjusted to a predetermined value.

In the fuel advance electronically controlled carburetor as described above, from the viewpoint that the carburetor is based on a constant nozzle pressure, the present invention aims to provide a fuel advance control carburetor with an upstream side of the main air passage in order to accurately catch changes in nozzle pressure caused by air flow. The pressure detection part of the valve regulator of the pressure regulating valve installed on the side is set as close as possible to the nozzle opening, and the leak side of the regulator to the atmosphere is duty controlled by a solenoid valve, so that the pressure detection part of the regulator is set as close as possible to the nozzle opening. The leak is small, and the leak is large during deceleration to reduce transient nozzle pressure fluctuations.Furthermore, the fuel control, which used to move the needle directly with the accelerator, has been replaced with a solenoid valve, and the solenoid valve is controlled by the command from the accelerator sensor. This signal is used to control the duty of the engine, and the throttle valve is actuated using this signal and the engine parameter signal, which has been improved to eliminate mechanical variations in fuel flow rate.

Next, the configuration of the present invention will be explained based on embodiments shown in the drawings.

What is shown in FIG. 1 is a schematic diagram of the fuel advance electronically controlled carburetor of the earlier application, in which 1 is the main air passage, 2 is the float chamber, 3 is the float, 4 is the float valve, and 5 is the main air passage. This is an air vent pipe that opens near the air inlet of the passage 1, and the inside of the float chamber 2 has a constant oil level at approximately atmospheric pressure.

The main air passage 1 is provided with a pressure regulating valve 7 connected to a valve regulator 6 on its upstream side, and a throttle valve 9 connected to a motor 8 on its downstream side.
A constant pressure section 1a is formed between these two valves 7 and 9, and a fuel nozzle 10 is connected to the constant pressure section 1a.
is open.

The nozzle 10 is connected to the float chamber 2 by a fuel passage 11.
A fuel adjustment needle valve 13 that is connected to the accelerator pedal is provided at the fuel inlet 12 of the vehicle. At the top of the needle valve 13, an accelerator lever 14 connected to an accelerator pedal A (not shown), an accelerator arm rotatably connected to the lever 14 via a spring,
A mechanism section 15 consisting of a potentiometer, a servo motor, etc. is provided, and the upper end of the needle valve 13 is connected to an accelerator arm of this mechanism section 15.

The minimum opening of the needle valve 13 is determined by the mechanism 15 to regulate engine idling, and the opening and maximum opening of the needle valve 13 are detected by a potentiometer, and the detected value is sent to the electronic control circuit C. The servo motor is controlled via the electronic control circuit C based on the detected value of the maximum opening degree and the detected values of necessary operating parameters such as engine speed and suction pipe negative pressure.
The maximum flow rate of fuel at each rotation speed of the engine, that is, the maximum opening degree of the needle valve 13 can also be achieved.

The valve regulator 6 of the pressure regulating valve 7 is connected to the valve 1
a regulator body 20 having an air chamber 19 formed by a diaphragm 13 provided with a diaphragm 13 and a spring 17; and a connecting rod 21 for opening and closing the regulating valve 7.
and a spring 22.
3 and a valve actuator 25 having an air chamber 24 formed by the regulator body 2.
0 air chamber 19 is connected to an orifice 27 by an air passage 26 that opens on the side wall of the constant pressure section 1a of the main air passage 1.
communicates with the constant pressure section 1a through the actuator 2.
The air chamber 24 of No. 5 communicates with the atmosphere side of the main air passage 1 through a leak passage 28 via an orifice 29, and furthermore, both chambers 19 and 24 communicate with the atmosphere side of the main air passage 1 through an orifice 29.
The structure is such that they communicate with each other through.

The regulator 6 is currently configured to handle, for example, an increase in suction pipe negative pressure caused by starting the engine or the throttle valve 9.
When the negative pressure in the constant pressure section 1a increases due to the opening operation of the
This negative pressure is transmitted to the air chamber 19 via the orifice 27, causing the diaphragm 18 to move to the right (in the figure) and widening the opening of the valve 16, so that the negative pressure in the air chamber 24 also increases, and the diaphragm 23 becomes connected. 21, and rotates the pressure regulating valve 7 in the opening direction to increase the amount of incoming air and weaken the negative pressure in the constant pressure section 1a.

In this case, the negative pressure inside the air chamber 24 is
Since the pressure regulating valve 7 is maintained at a certain negative pressure value by the atmospheric air flowing in through the pressure regulating valve 7, the pressure regulating valve 7 is also held at a certain opening degree. Then, when the negative pressure in the constant pressure section 1a weakens, the operation opposite to that described above is performed, and the operation is performed so as to always quickly recover the pressure fluctuations in the constant pressure section 1a, so that the negative pressure in the constant pressure section 1a is always maintained almost constant. It is being done.

The throttle valve 9 is driven via a valve motor 8 operated by an electronic control circuit C, and its opening is within a predetermined opening of the needle valve 13.
It is determined by the electronic circuit C according to the fuel flow rate of 1.

The above is the fuel advance electronically controlled carburetor according to the earlier application which is the object of the invention in this application.

The present invention is directed to the above-mentioned fuel advance electronically controlled carburetor, as shown in FIG. The pressure outlet 26a of the passage 26 is located as close as possible to the opening 10a of the nozzle 10, for example, the nozzle 10
A leak passageway 28 to the atmosphere side of the air chamber 24 of the valve actuator 25 is provided adjacent to the opening 10a of the valve actuator 25 to detect acceleration/deceleration from the accelerator sensor A _S and to perform duty control via the electronic control circuit C. A solenoid valve 30 is provided, and the solenoid valve 3
0 duty control to reduce leakage during acceleration and increase leakage during deceleration to reduce transient nozzle pressure fluctuations.
3 replaces this with a fuel adjustment valve 13a having a solenoid 31, and controls the duty of the solenoid 31 based on the command from the accelerator sensor A _S , and controls the throttle valve 9 using this command signal and the engine parameter signal.
It is designed to operate.

Fuel adjustment valve 13a having the above-mentioned solenoid 31
The deceleration, low temperature, high temperature, atmospheric pressure correction, and idle up are operated by commands through the electronic control circuit C based on information from various sensors such as the accelerator sensor A _S. C, temperature 32,
Air pressure 33, engine speed 34, intake pressure 35,
Each detection signal of the nozzle pressure 36 is input.

In the above configuration, the pressure outlet (pressure detection part) 26a of the valve regulator 6 may be formed concentrically with the outer periphery of the opening 10a of the nozzle 10, as shown in FIG. Note that 37 is an accelerator lever connected to an accelerator pedal A (not shown).

As described above, the present invention provides a fuel advance electronically controlled carburetor in which the pressure detection part of the valve regulator of the pressure regulating valve is provided at a position as close as possible to the opening of the fuel nozzle, so that the nozzle pressure due to the airflow is reduced. Changes can be accurately captured and the influence of air flow can be reduced.In addition, acceleration and deceleration from the accelerator sensor is detected in the leak passage to the atmosphere side of the valve actuator of the pressure regulating valve, and duty control is performed via an electronic circuit. A solenoid valve is provided, and the solenoid valve reduces the leakage in the leak passage during acceleration and increases it during deceleration, so that fluctuations in nozzle pressure due to throttle operation can be reduced (improved response). It can also be used to control the air-fuel ratio at low temperatures.Furthermore, since the fuel adjustment valve uses a solenoid valve whose duty is controlled by commands from the accelerator sensor, it not only eliminates mechanical variations, but also reduces the fuel flow rate. Calculations become easier, and fuel control such as deceleration, low temperature, high temperature, atmospheric pressure correction, and idle up can be freely performed using electronic circuits and computers, which has the effect of significantly improving the performance of fuel advance electronically controlled carburetors.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a fuel advance electronically controlled carburetor, FIG. 2 is a schematic diagram showing an embodiment of the fuel advance electronically controlled carburetor of the present invention, and FIG. 3 is a cross section showing another example of the pressure detection part of a valve regulator. It is a diagram. 1: Main air passage, 1a: Constant pressure section, 2: Float chamber, 4: Float valve, 5: Air vent pipe, 6: Valve regulator, 7: Pressure adjustment valve, 8: Motor,
9: Throttle valve, 10: Fuel nozzle, 11: Fuel passage, 12: Fuel inlet, 13a: Fuel adjustment solenoid valve, 25: Valve actuator, 26a: Pressure outlet (pressure detection part), 28: Leak passage, 3
0: Solenoid valve, 31: Solenoid, 32-3
6: Detection signal, A _S : Accelerator sensor, C: Electronic control circuit.

Claims (1)

[Claims] 1. A pressure regulating valve is provided on the upstream side of the main air passage, and a throttle valve is provided on the downstream side. A fuel nozzle is provided in the constant pressure section of the main air passage formed between these two valves. The fuel inlet is connected to the bottom of the float chamber forming a constant pressure oil level, and the fuel inlet thereof is provided with a fuel adjustment valve that is linked to the accelerator pedal, and also controls the throttle valve opening according to the fuel flow rate of the fuel nozzle. In a fuel advance electronic control carburetor equipped with an electronic control circuit and configured to adjust the air-fuel ratio to a predetermined value,
The output detection part of the valve regulator of the pressure regulating valve is set as close as possible to the opening of the fuel nozzle, and the leak passage from the accelerator sensor to the atmosphere side of the valve actuator of the pressure regulating valve is set as close as possible to the opening of the fuel nozzle. A fuel adjustment device that is provided with a solenoid valve that detects acceleration and deceleration and is duty-controlled via an electronic control circuit, and further includes a solenoid that is duty-controlled by a command from the accelerator sensor as a fuel adjustment device that is linked to the accelerator pedal. The fuel regulating valve is provided with a solenoid and is configured such that deceleration, low temperature, high temperature, pressure correction, and idle up are activated by commands through the electronic control circuit of each sensor. Features a fuel advance electronically controlled carburetor.