JPH0544539Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a fuel injector suitable for use in injecting and supplying fuel to, for example, a four-valve automobile engine.

[Conventional technology]

Generally, in a 4-valve engine, etc.
For each cylinder, for example, two intake valves and two exhaust valves are provided at the cylinder head.

Therefore, FIGS. 8 and 9 show a fuel injection device for a four-valve engine according to this type of prior art.

In the figure, 1 indicates an engine body (only a portion corresponding to one cylinder of a multi-cylinder engine is shown), and the engine body 1 includes cylinders (not shown).
A cylinder head 1A is mounted on the top, and inside the cylinder head 1A are two intake ports and two exhaust ports (none of which are shown) that communicate with the inside of the cylinder, and two ports that open and close each intake port. Intake valves 2, 2 and two exhaust valves 3, 3 for opening and closing each exhaust port are provided.

Reference numeral 4 indicates an intake pipe consisting of an intake manifold, etc., and the tip side of the intake pipe 4 is provided with, for example, two branch pipes 4A, 4A, and the tip of each branch pipe 4A is connected to each intake port of the cylinder head 1A. It is connected to the. The intake pipe 4 has an injector mounting portion 4B (hereinafter referred to as
A mounting portion 4B) is provided, and a fuel injector 6, which will be described later, is attached to the mounting portion 4B. Further, a throttle valve (not shown) is provided in the middle of the intake pipe 4, and adjusts the amount of intake air sucked into the cylinder according to the amount of depression of the accelerator pedal (not shown). . Also, 5
indicates an exhaust pipe consisting of an exhaust manifold and the like connected to the exhaust port of the cylinder head 1A.

Reference numeral 6 indicates a fuel injector as a fuel injection valve attached to the attachment part 4B of the intake pipe 4 via a fixing member 7, etc. The fuel injector 6 includes an injector body 6A having a built-in electromagnetic actuator, etc. , a valve body 6B provided on the tip side of the injector body 6A, and a valve body 6D (see FIG. 8), which is actuated by the electromagnetic actuator and is a needle valve or the like that opens and closes the injection port 6C of the valve body 6B. The valve body 6
A pintle 6E is integrally formed at the protruding end of D. The fuel injector 6 is configured to inject fuel supplied under pressure from a fuel pump (not shown) from an injection port 6C.

In the conventional technology configured as described above, when an injection pulse is applied from the outside to the electromagnetic actuator in the injector main body 6A, the valve body 6D is opened by the electromagnetic actuator as shown in FIG.
Each branch pipe 4A from the injection port 6C of the valve body 6B
Fuel is injected into the tank. In this case, the valve body 6
Since a pintle 6E is provided at the tip of D, the fuel from the injection port 6C collides with the pintle 6E, becomes atomized into fine particles, and is ejected as shown in the figure. Then, this injected fuel mixes with the intake air in the intake pipe 4 and becomes an air-fuel mixture and is sucked into the cylinder of the engine body 1. After being converted into fuel in this cylinder, it becomes exhaust gas and enters the exhaust pipe 5. It is sequentially discharged to the outside.

[The problem that the idea aims to solve]

However, in the above-mentioned conventional technology, the injected fuel from the injection port 6C is only atomized by colliding with the pintle 6E, and most of the injected fuel adheres to the wall surface 4C of the intake pipe 4 and forms a liquid wall. This has the disadvantage that a film flow occurs, which reduces combustion efficiency and increases the HC concentration in the exhaust gas.

In addition, as shown in FIG. 10, the valve body 6B
Attach the separator 8 to the tip of the separator 8.
Other conventional techniques are also known in which the injected fuel is divided into two directions and ejected from the two ejection holes 8A, 8A drilled in the intake pipe 4 to prevent the injected fuel from adhering to the wall surface 4C of the intake pipe 4. It is being However, in this case, since the fuel is ejected in liquid form from each ejection hole 8A of the separator 8, the atomization and mixing properties of the fuel are poor, and the ejected fuel also adheres to the valve body of the intake valve 2, etc. A liquid film is formed, and when the intake valve 2 is opened, particles with a large particle size are sucked into the cylinder and adhere to the cylinder wall surface as a thick liquid film, increasing the flame-extinguishing area within the cylinder and reducing the exhaust gas. The disadvantage is that the HC concentration in the gas increases.

The present invention was developed in view of the above-mentioned shortcomings of the conventional technology. It provides Ekta.

[Means to solve the problem]

The features of the configuration adopted by the present invention in order to solve the above-mentioned problems include: a nozzle section on the distal end surface of the valve body; a plurality of inflow holes located on the inlet side of the nozzle section and communicating with the inside of the valve body; one or more ejection holes located on the outlet side of the nozzle portion in communication with the inflow hole, and having a spiral groove in a single swirl direction formed on the circumferential surface; Provide a nozzle member consisting of a spout that determines the
Each inflow hole of the nozzle member is inclined at a predetermined angle with respect to the nozzle in order to guide the fuel toward the spiral groove of the nozzle, and the nozzle member allows the fuel from each inflow hole to flow in a swirling manner through the spiral groove. The reason is that it has a structure that allows it to erupt.

[Effect]

With the above configuration, when fuel is injected from the valve body, the fuel is guided through each inflow hole to the spiral groove formed on the circumferential surface of the nozzle, and is rotated in a single rotation direction by the spiral groove. The spray is ejected from the nozzle in a swirling flow state, with the spray angle being determined by the nozzle.

〔Example〕

Embodiments of the present invention will be described below with reference to FIGS. 1 to 7. In the embodiment, the same components as those of the prior art shown in FIG. 8 described above are given the same reference numerals, and their explanations will be omitted.

1 to 5 show a first embodiment of the present invention.

In the figure, 11 indicates a fuel injector that is attached to the attachment part 4B of the intake pipe 4 via the fixing member 7, etc., and the injector 11 includes an injector main body 13 having a built-in electromagnetic actuator 12,
A valve body 15 is provided on the tip side of the injector body 13 via a holder 14, and has a valve seat 15A and an injection port 15B formed on the inner periphery of the tip side. When the coil 12A of the actuator 12 is excited, it is attracted to the core cylinder 12B together with the anchor 16 to open the valve seat 15A, and the needle valve 18 is normally closed by the spring 17, and the needle valve 18 is opened. The holder 14 and the valve body 1
5, and a stopper 19 provided on the base end side of the injector body 13, and the stopper 19 provided between the coil
2A, a filter 21 attached to the outer circumferential side of the injector body 13 so as to cover the fuel inlet/outlet port 13A formed in the injector body 13, and a plate nozzle 2 to be described later.
It is roughly composed of 2.

Reference numeral 22 indicates a plate nozzle as a nozzle member provided on the distal end side of the valve body 15 via a nozzle holder 23 so as to cover the injection port 15B.The plate nozzle 22 is made of a metal material such as stainless steel. It is formed as shown in the figure and is generally composed of a substantially cylindrical nozzle portion 22A and a substantially disk-shaped plate portion 22B protruding in the radial direction from the outer periphery of the proximal end of the nozzle portion 22A. The plate nozzle 22 is connected to the valve body 15 via the plate portion 22B by the nozzle holder 23.
It is removably attached to the tip side of the plate part 2.
2B is adapted to come into liquid-tight contact with the distal end surface of the valve body 15.

Further, the nozzle portion 22A of the plate nozzle 22
As shown in FIGS. 2 to 5, a pair of inlet holes 22C, 22C are located on the inlet side and communicate with the injection port 15B of the valve body 15, and are formed with a predetermined distance apart in the diametrical direction, and an outlet. Outflow as a pair of ejection holes located on the side and communicating with each of the inflow holes 22C, and having a double thread-shaped spiral groove 22D formed on the circumferential surface to rotate in the direction of arrow B, which is a single rotation direction described later. There are provided holes 22E, 22E, and a pair of jet ports 22F, 22F located on the tip side of each of the outflow ports 22E and formed to have a diameter equal to or larger than each of the outflow ports 22E, and each of the jet ports 22F is As shown in FIG. 3, the fuel spray angle θ is determined by the ratio between the diameter d and the depth h.

Here, each outlet hole 22 of the plate nozzle 22
E and each injection port 22F are inclined outward in the radial direction of the nozzle portion 22A at a predetermined angle in correspondence with each branch pipe 4A of the intake pipe 4 shown in FIG. It is inclined radially inward at a predetermined angle toward the peripheral surface of each outflow hole 22E in order to guide it in the direction of arrow A in FIG. 3 toward the spiral groove 22D of each outflow hole 22E. And each inflow hole 2
Fuel flowing in the direction of arrow A from 2C is swirled in the direction of arrow B by swirling along the spiral groove 22D of each jet port 22E, and swirls from each jet port 22F with a spray angle θ. The liquid is ejected into each branch pipe 4A in a flowing state. In this case, the spray angle θ can be appropriately selected depending on the diameter d and depth h of the angular jet nozzle 22F.

The fuel injector 11 according to this embodiment has the above-mentioned configuration.Next, regarding its operation, the injector 11 is replaced with the conventional injector 6 at the attachment part 4B of the intake pipe 4 shown in FIG. The explanation will be given using an example where it is installed.

First, an injection pulse is applied to the coil 12A of the electromagnetic actuator 12 from the outside via the connector 20, and when the coil 12A is excited, the core cylinder 12
A magnetic force is generated in B, and the needle valve 18 is connected to the anchor 16.
At the same time, it is sucked into the core cylinder 12B side, opens the valve seat 15A side of the valve body 15, and injector body 1
3 is injected from the injection port 15B. Then, the fuel from the injection port 15B flows into each inlet hole 22C of the plate nozzle 22, is branched into two directions, and flows into each injection port 22F in the direction of arrow A in FIG. , a swirl is applied in the direction of arrow B along each spiral groove 22D, and each spout 2
It is sprayed from 2F in a hollow conical shape with a spray angle θ in a swirling flow state.

Thus, according to this embodiment, the valve body 1
By guiding the fuel injected from the injection ports 15B of No. 5 into the spiral groove 22D through the respective inflow holes 22C that are inclined radially inward on the circumferential surface side of each injection port 22E, the fuel injected from the injection ports 15B of No. By the cooperation of the spiral grooves 22D and the spiral grooves 22D, it is possible to effectively swirl the fuel in the direction of arrow B, which is a single swirling direction, and the fuel is sprayed through each jet port 22F while determining the spray angle θ. They are each injected in a swirling flow state, and a hollow conical spray pattern can be easily obtained.

Therefore, according to this embodiment, the fuel ejected from each ejection port 22F is fed to each branch pipe 4A shown in FIG.
The fuel can be branched in two directions and injected into the intake pipe 4, which effectively prevents the injected fuel from adhering to the wall surface 4C of the intake pipe 4, etc., and by ejecting the fuel in a swirling flow state, the atomization of the fuel can be promoted, and the atomization and mixing properties can be improved.

Further, since the plate nozzle 22 can appropriately select the spray angle θ based on the ratio between the diameter d and the depth h of each jet nozzle 22F, the fuel from each jet nozzle 22F can be distributed to each branch shown in FIG. The fuel can be sprayed in a hollow conical shape at an optimal spray angle θ to the outer periphery of the valve body of each intake valve 2 through the pipe 4A, and as described in the prior art, fuel adheres to the valve body of each intake valve 2. This can effectively suppress the formation of a liquid film. Then, when each intake valve 2 is opened, this injected fuel becomes a uniform air-fuel mixture and is sucked into the cylinder from the outer periphery of the valve body of the intake valve 2 together with the intake air, promoting secondary atomization. This provides various effects, such as preventing fuel from adhering to the cylinder wall as a liquid film, increasing combustion efficiency, and effectively reducing the HC concentration in exhaust gas.

Next, FIGS. 6 and 7 show a second embodiment of the present invention, and the feature of this embodiment is that two inflow holes are formed on the inlet side of the nozzle member, and each inflow hole is formed on the outlet side. This is due to the formation of an ejection hole that communicates with the In addition,
In this embodiment, the same components as in the first embodiment are given the same reference numerals, and their explanations will be omitted.

In the figure, numeral 31 indicates a plate nozzle as a nozzle member attached to the tip side of the valve body 15 via the nozzle holder 23, and the plate nozzle 31 is almost the same as the plate nozzle 22 described in the first embodiment. Although it consists of a nozzle part 31A and a plate part 31B, the nozzle part 31A has
The injection port 15 of the valve body 15 is located on the inlet side.
two inflow holes 31C, 31C that communicate with B, and an outflow hole 31E, which is located on the exit side and communicates with the inflow hole 31C, and serves as an ejection hole having a double-threaded spiral groove 31d formed on the circumferential surface. and a jet nozzle 31F which is located on the tip side of the outflow hole 31E and determines the spray angle θ based on the ratio of the diameter d and the depth h.

In addition, each inlet hole 31C is formed obliquely in order to guide the fuel from the injection port 15B toward the spiral groove 31D of the outlet hole 31E, and is diametrically opposed to each other as shown in FIG. It is inclined towards the direction. The fuel from each inflow hole 31C is swirled by the spiral groove 31D of the outflow hole 31E, and is ejected from the ejection port 31F in a hollow conical shape in a swirling flow state.

Thus, in this embodiment configured in this way, it is possible to obtain almost the same effects as in the first embodiment, and it is possible to improve the atomization and mixing properties of the fuel, improve the combustion efficiency, and reduce the exhaust gas. can reduce the HC concentration in Further, since it is only necessary to form one outflow hole 31E and one jet port 31F in the nozzle portion 31A, the structure can be simplified, and various effects such as cost reduction can be achieved.

In the second embodiment, the plate nozzle 31 has two inflow holes 31 that communicate with the outflow hole 31E.
Although it has been described that three or more inlet holes 31C are formed, three or more inflow holes 31C may be formed instead. Further, in the first embodiment as well, a plurality of inflow holes 22C may be formed for each outflow hole 22E.

Further, in each of the above embodiments, the spiral grooves 22D, 31
Although it has been described that D is formed into a double-thread shape, this is not limited to a double-thread shape, but may also be a multi-thread shape with 3 or more threads, and in some cases, a 1-thread thread shape may be used.
It may also be in the form of a threaded thread.

[Effect of idea]

As detailed above, according to the present invention, a plurality of inflow holes are formed on the tip surface of the valve body, and one or more spiral grooves communicating with each of the inflow holes and having a single spiral groove formed on the circumferential surface thereof are provided. A nozzle member consisting of a nozzle hole and a nozzle port that determines the spray angle of fuel on the downstream side of the nozzle hole is provided, and the fuel guided to the nozzle through each inflow hole is jetted out in a swirling flow state through a spiral groove. Because of this structure, each inlet hole and the spiral groove work together to effectively swirl the fuel in a single direction, and the fuel is sprayed into a hollow conical shape at a predetermined spray angle. It can be squirted.

As a result, it is possible to promote fuel atomization, improve atomization and mixing properties, and effectively prevent fuel from adhering to walls, increasing fuel efficiency and reducing HC in exhaust gas.
concentration can be reduced.

[Brief explanation of the drawing]

1 to 5 show a first embodiment of the present invention, in which FIG. 1 is a longitudinal sectional view of the injector, FIG. 2 is a longitudinal sectional view of the plate nozzle, and FIG. FIG. 4 is a plan view of FIG. 2, FIG. 5 is a bottom view of FIG. 2, FIGS. 6 and 7 show the second embodiment, and FIG. FIG. 7 is a plan view of FIG. 6, FIGS. 8 and 9 show the prior art, and FIG.
The figure is a plan view of the main parts broken away showing the state in which the fuel injection device is assembled to the engine, FIG. 9 is a longitudinal cross-sectional view of the main parts of the injector, and FIG.
It is a longitudinal cross-sectional view similar to the figure. 1... Engine body, 1A... Cylinder head, 2... Intake valve, 3... Exhaust valve, 4... Intake pipe, 4A... Branch pipe, 4B... Injector mounting part, 11... Fuel injector , 12...
Electromagnetic actuator, 13... Injector body, 15... Valve body, 15A... Valve seat, 1
5B...Injection port, 18...Needle valve, 22,3
1...Plate nozzle (nozzle member), 22A,
31A... Nozzle part, 22B, 31B... Plate part, 22C, 31C... Inflow hole, 22D, 31
D... Spiral groove, 22E, 31E... Outflow hole (spout hole), 22F, 31F... Spout port, 23... Nozzle holder.

Claims (1)

[Scope of utility model registration request] An injector body with a built-in electromagnetic actuator, and an injector body provided on the tip side of the injector body,
A cylindrical valve body with a valve seat formed on the inner peripheral side of the tip, and a needle valve that is slidably inserted into the valve body and is operated by the electromagnetic actuator to open and close the valve seat of the valve body. In the fuel injector, the distal end surface of the valve body includes a nozzle portion, a plurality of inflow holes located on the inlet side of the nozzle portion and communicating with the inside of the valve body, and a plurality of inflow holes communicating with the inflow holes and communicating with the inside of the valve body. A nozzle consisting of one or more nozzle holes located on the exit side of the section and having a spiral groove in a single swirling direction formed on the circumferential surface, and a nozzle that determines the fuel spray angle downstream of the nozzle holes. A member is provided, each inlet of the nozzle member is inclined at a predetermined angle with respect to the nozzle to guide the fuel toward the spiral groove of the nozzle, and the nozzle is configured to guide the fuel from each inlet through the spiral groove. A fuel injector characterized by being configured to eject in a swirling flow state.