JPS59170465A - Fuel control device - Google Patents

Abstract

PURPOSE:To avoid stagnation of fuel around a valve in the upper stream of an air control valve by providing an inlet port of a bypass passage on the upper stream side of a throttle valve to be in the upper side of a fuel corn injected from a fuel injection valve. CONSTITUTION:An air passage bypassing a throttle valve consists of upper stream passages 6b, 6c, 6d and a lower stream passage 6e of a valve 4. The entrance 6a of this bypass passage is provided on the upper side of a cone 15 of the fuel injected from a fuel injection valve 2 and prevents the fuel from flowing into the bypass passage 6b. The axial centers of the passages 6b, 6c and 6d are positioned successively at upper positions as they go from upper to lower stream. In this construction, it is difficult for fuel to flow into the lower stream passages even if the fuel flows into the passage 6a by mistake.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a single point fuel control system for supplying a mixture to an internal combustion engine.

[Prior art]

In a single-point fuel control system where a fuel injection valve is installed upstream of the throttle valve and supplies air-fuel mixture to the engine, is the throttle valve used for the idle rotation side (goods) when the cooler is loaded or when starting and warming up? A soot control device has been provided in which an air control valve is placed in a bypass passage to control the idle air flow rate. However, the fuel control device with this structure is nitrogen control IgI9? Is there fuel in the bypass passage near the valve upstream of the air control valve when the valve is closed? When activated, this fuel flows out, which has the disadvantage of making the air-fuel mixture too rich.

FIG. 1 is an example of a conventional point-type fee control device. Fuel is supplied to the engine by a fuel injection valve 2 installed in the intake cylinder 3 upstream of a throttle valve 5 located in the intake cylinder 8 which supplies air to the engine and controls the air flow rate.

The main body l is provided with an air passage 6 that completely bypasses the throttle valve 5.
111 0N-OFF valve 4 is arranged, and this ON/OFF valve 4 is arranged.
By opening the four OFF valves, the idle airflow needle is increased and the idle speed is controlled to an appropriate value when the cooler is loaded or when starting and warming up. In the single-point fuel control device that operates in this manner, as described above, the fuel injected from the fuel injection valve 2 enters from the bypass passage entrance 6a, causing the 0N-OF
When the F pulp 4 is not operating, fuel accumulates in the upstream passage 7 near the pulp. Therefore, when the ON/OFF pulp is activated, this accumulated fuel instantly enters the engine through the bypass passage 6, causing harmful components such as C09HC to enter the exhaust gas.
Not only does this result in a loss of fuel economy, but in severe cases Vi,
The engine stops.

[Purpose of the invention]

The present invention has been proposed in order to solve these shortcomings, and has two objects to provide a single-point fuel control device in which fuel does not accumulate near the valve upstream of the air control valve.

[Summary of the invention]

The present invention has a throttle valve installed above the cone of fuel injected from the fuel injection valve, and
The inlet of the J air passage is also located above the air metering part of the gust control valve.

[Embodiments of the invention] The present invention will be described in detail below with reference to the drawings.

In FIG. 2, the air path IIvi bypassing the throttle valve is
Upstream passages 6b and 6c of ON/OFF pulp 4.

6d and downstream @6e. The inlet 6a of this bypass passage is provided above the cone 15 of fuel injected from the fuel injection valve 2, and prevents fuel from flowing into the bypass passage 6b.

Also, the upstream passages 6b and 6C of the ON-OFF valve 4.

6d has a structure in which the axial center of the passage faces upward as it goes from the upstream passage to the downstream passage, and even if the fuel flows into the passage 6a, it is difficult to flow into the downstream passage.

The above structure not only prevents fuel from flowing into the bypass passage 6bK, but also turns on and off the fuel that does flow into the bypass passage 6bK.
A block near the seat portion ioo of the OFF valve 4 prevents a problem in which water flows into the engine through the downstream passage 5ei when the valve 4 is operated.

FIG. 3 shows a second embodiment. As in the previous embodiment, the bypass air passage inlet 1102 is disposed above the entire fuel cone 15 to prevent fuel from flowing into the bypass passage @110. Furthermore, in this embodiment, the proportional control valve 120 has a metering section 130 vertically above the bypass passage 110b. It is installed.

With such a passage configuration, the fuel that has flowed into the universal @tlob will not flow out to the downstream passage 110c through the metering section 130, and fuel will not accumulate near the proportional control valve 4 as in the above-mentioned embodiment. Is this a problem where this fuel flows out when multiple valves are activated? It can be prevented. Further, even when the proportional control valve 4 is in operation, it is possible to prevent deterioration in the greenness of the valve due to the passage of fuel through the meter part 130.

[Brief explanation of drawings]

Figure 1 is a cross-sectional view showing a conventional example, Figure 2 is a cross-sectional view of a simple embodiment of the present invention, and Figure 3 is a cross-sectional view of another embodiment. 4... Pulp, 6a... 4th road entrance, 6a-d...
Upper lft, 1st plan

Claims (1)

[Claims] ■Is there air in i & Seki? an intake passage to supply air, a throttle valve provided in the intake passage, a fuel injection valve located upstream of the throttle valve and opening into the intake passage, a bypass 1 outlet connecting the upstream and downstream of the throttle valve, and the A fuel control device comprising an air control valve provided in a passage, characterized in that the fuel control device is provided at an inlet of the bypass passage on the upstream side of the throttle valve or above a fuel cone injected from the fuel injection valve.