JPH04325768A - Solenoid type fuel injection valve - Google Patents

Abstract

PURPOSE:To prevent fuel drops from being accumulated between a fuel valve body and an air valve body in a fuel injection valve formed in such a way as to feed auxiliary air down below a fuel seal part to atomize fuel spray by providing an air valve for adjusting the auxiliary air quantity interlockingly with the fuel valve body. CONSTITUTION:A fuel valve body 1 normally pressed to a fuel seal part 6 by an elastic means 5 is connected to a movable element 2 and opened being sucked to the fixed element core 4 side by applying a current to a coil 3. Fuel is supplied from a fuel feed pipe 13 being pressurized to higher pressure than auxiliary air pressure, and passes the gap of the fuel seal part 6 at the valve opening action time so as to be injected from a nozzle 7. Atomizing auxiliary air is fed by an auxiliary air passage 8 so as to atomize the fuel at the fuel injecting time. In this case, an air valve 10 is fixed to the fuel valve body 1 and opened/closed in association with the motion of the fuel valve body 1. The gap of the air valve 10 is enlarged in association with the opening action of the fuel valve to inject supplied air together with injected fuel.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic fuel injection valve and a fuel supply system applied to engines such as automobiles.

0002

2. Description of the Related Art An example of a fuel injection device that controls the amount of auxiliary air in synchronization with fuel injection can be found in Japanese Patent Laid-Open No. 2-181067.

0003

[Problems to be Solved by the Invention] However, in the above-mentioned conventional technology, it is necessary to provide an electromagnetic control means separate from the fuel injection valve to control the amount of auxiliary air, which complicates the mechanism and is disadvantageous in terms of cost. There was a problem that.

An object of the present invention is to control the amount of auxiliary air in synchronization with fuel injection with a simple structure in an electromagnetic fuel injection valve that uses auxiliary air for fuel atomization, and to prevent the fuel seal from being obstructed. Our goal is to supply electromagnetic fuel injection valves and fuel supply devices that are not available in Japan.

A further object of the present invention is to provide an electromagnetic fuel injection valve having a structure in which fuel that is not atomized by auxiliary air does not accumulate between the fuel valve element and the air valve element.

[0006]

[Means for Solving the Problems] The above object is achieved by providing an air amount control valve which is fixed to a fuel valve body for controlling the amount of fuel and operates in conjunction with the same.

[0007] Furthermore, the above object is achieved by establishing a dimensional relationship that prevents the air valve from being completely closed even when the fuel valve is closed.

[0008]

[Operation] When the fuel valve body is in the closed position, the air valve keeps the air passage area small and does not supply unnecessary air, and opens as the fuel valve body performs the valve opening operation. Supplies auxiliary air necessary for fuel atomization.

Furthermore, even when the fuel valve body is in the closed position, the auxiliary air flows through the air valve gap, so that fuel is supplied to the downstream portion of the fuel valve body and the upstream portion of the air valve without accumulating.

Furthermore, the closed position of the fuel valve element is not restricted by the closed position of the air valve element, so that fuel sealing is not obstructed.

[0011]

Embodiment (1) FIG. 1 shows an embodiment of an electromagnetic fuel injection valve to which the present invention is applied. In FIG. 1, a fuel valve body 1 is coupled to a movable element 2, and when a coil 3 is energized, it is attracted to a stator core 4 side and performs a valve opening operation. The fuel valve body is normally pressed against the fuel seal 6 by elastic means 5. Fuel is supplied from the fuel supply pipe 13 under pressure higher than the auxiliary air pressure, and is injected from the nozzle 7 through the gap in the fuel seal portion 6 during the valve opening operation. On the other hand, the auxiliary air for atomization is supplied from the auxiliary air passage 8, and the supply pressure is kept higher than the pressure of the injection atmosphere 9. The air valve 10 is fixed to the fuel valve body 1 and opens and closes as the fuel valve body 1 moves. When the air valve 10 is in the closed position, the air flow rate is smaller than when it is in the open position.

When the fuel valve body 1 is closed, the air valve 10 gap is small, so the amount of air flowing is small. As the fuel valve body 1 opens, the air valve 10 gap becomes larger, and the supplied air is injected together with the injected fuel.

(2) Here, when the fuel valve body 1 is closed, the air valve 1
By setting 0 to a dimensional relationship that does not completely close the valve, the following actions and effects can be obtained.

When the fuel valve body 1 is closed, the fuel remaining in the space 11 downstream of the fuel valve body and upstream of the air valve from the air valve 10 gap is discharged (injected) together with the auxiliary air, so that it is metered and injected at the fuel valve section. All fuel is supplied to the injection atmosphere 9, and the provision of the air valve 10 does not affect the accuracy of the fuel injection amount.

Furthermore, when the fuel valve body 1 is in the closed position, it is necessary to completely seal the fuel, but since the closed position of the air valve 10 leaves a gap in the axial direction, the fuel valve body 1 The elastic means 5 reliably has its axial position unrestricted.
It is possible to contact the fuel seal portion 6 and seal the fuel. A similar effect can also be obtained by connecting the fuel valve body 1 and the air valve 10 with an elastic joint 14 so as to contract in the axial direction with a force smaller than the valve-closing force of the fuel valve body 1 (Fig. 2c).

(3) The fuel valve body 1 and the air valve 10 may be integrally formed as shown in FIG. 2A, but as shown in FIG. By combining the above, it is possible to relatively easily obtain a dimensional relationship in which the open area of the auxiliary air amount adjusting section 15 is larger than the open area of the fuel seal section 6. With such a dimensional relationship, it is possible to eliminate the influence of the presence of the air valve 10 on the fuel metering accuracy.

(4) The amount of fuel to be injected is measured near the fuel valve body 1, and here the fuel supply pressure is adjusted to the air pressure in the space 11 downstream of the fuel valve body and upstream of the air valve, and thus to the supply pressure of auxiliary air. However, by keeping the amount constant, the injected fuel can be measured with high accuracy. FIG. 3 shows a simple fuel system piping diagram when controlling the fuel supply pressure in this manner.

[0018]

Effects of the Invention According to the present invention, there is provided an electromagnetic fuel injection valve and fuel that have a simple structure, are highly reliable, and are equipped with an atomization mechanism using auxiliary air that controls the amount of auxiliary air in synchronization with fuel injection. Can supply supply equipment.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view of an electromagnetic fuel injection valve showing one embodiment of the present invention.

2 is a diagram illustrating details of the vicinity of the valve body in FIG. 1 and a method for connecting the valve body; FIG.

FIG. 3 is a diagram showing a configuration example of a fuel supply device using the electromagnetic fuel injection valve of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1...fuel valve body, 2...mover, 3...electromagnetic coil, 4...stator core, 5...elastic means, 6...fuel seal part, 7...nozzle, 8...auxiliary air passage, 9...injection atmosphere, 10... air valve,
10'...Air valve as a separate member, 11...Space downstream of the fuel valve body and upstream of the air valve, 12...Yoke, 13...Fuel supply pipe, 14
... Elastic body, 15... Auxiliary air amount adjustment section, 16... Fuel pump, 17... Auxiliary air pump, 18... Control unit, 19... Differential pressure regulator, 20... Fuel injection valve, 21... Fuel tank.

Claims (7)

[Claims] Claim 1: A stator core made of a magnetic material inserted through the center of an annular electromagnetic coil, which is placed facing the tip of the stator core and is connected to a fuel valve body to open the valve by magnetic attraction. A movable element made of a magnetic material, a fuel valve body fixed to the movable element or formed integrally with the movable element, a yoke that is located on the outer periphery of the coil and forms a magnetic circuit together with the core and the movable element, and the movable element. It consists of an elastic means that is biased in the opposite direction to the core, and a seal section that seals the fuel by pressing the fuel valve element with the elastic means.The opening and closing operation of the fuel valve element is controlled by energizing the coil, and the fuel is removed. In a device that has a function of controlling the injection amount and further has a mechanism that promotes atomization of the fuel spray by supplying auxiliary air below the fuel seal, the auxiliary air amount is adjusted in conjunction with the fuel valve body. An electromagnetic fuel injection valve characterized by having an air valve. 2. The electromagnetic fuel injection valve according to claim 1, further comprising an air valve having dimensions that allow air to pass through the fuel valve body without completely closing the valve even when the fuel valve body is closed. 3. A fuel supply device comprising the electromagnetic fuel injection valve according to claim 1. 4. The electromagnetic fuel injection valve according to claim 1, wherein the air valve is integrally formed with the fuel valve body. 5. Claim 1, characterized in that an air valve as a separate member is attached to the tip of the fuel valve body, below the fuel sealing surface.
Or 2 electromagnetic fuel injection valves. 6. The electromagnetic fuel according to claim 1, wherein the dimensional relationship is such that the area of the auxiliary air amount adjusting part when the valve is open is larger than the area of the fuel seal part when the valve is open. injection valve. 7. The electromagnetic fuel injection valve according to claim 1, further comprising a mechanism for adjusting the fuel supply pressure to be constant with respect to the pressure between the fuel sealing surface and the air amount adjusting section.