JPH07127550A - Jet regulating plate for fuel injection valve and manufacture thereof - Google Patents

Abstract

PURPOSE:To manufacture a jet regulating plate simply by forming a chamfer part on the opening part of a orifice hole easily. CONSTITUTION:A jet regulating plate 1 is punched by a punch 33 with an inclining angle alpha, orifice holes 2a, 2b are drilled by the punching part 33a of the punch 33, the punch 33 is further lowered, a press-in part 33b on the base end side of the punch 33 is pressed-in the orifice holes 2a, 2b, and a chamfer 3 is formed on the opening part of the orifice holes 2a, 2b. It is thus possible to easily form the chamber part 3 by one penetrating work in respective orifice holes 2a, 2b even if a plurality of orifice holes 2a, 2b is dispersed and arranged on the jet regulating plate 1 and centering work is difficult, since the chamfer part 3 is formed simultaneously when the orifice holes 2a, 2b is penetrating worked.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a jet flow adjusting plate of a fuel injection valve and a method of manufacturing the same, and more specifically, to a fuel which is disposed downstream of an injection hole of a fuel injection valve and is injected from the injection hole. The present invention relates to a jet flow adjusting plate for adjusting the spray shape and the injection amount of, and a method for forming an orifice hole of the jet flow adjusting plate.

[0002]

2. Description of the Related Art Conventionally, there has been a fuel injection valve that uses a jet adjusting plate to adjust a spray shape injection amount of fuel when injecting and supplying the fuel into an intake manifold of an engine. As an example thereof, the one shown in FIG. 6 can be cited.

FIG. 6 is an enlarged sectional view showing a jet flow adjusting plate of a conventional fuel injection valve.

As shown in the figure, a needle 13 is provided in the inner case 14 on the tip side of the fuel injection valve, and a valve element 13 a formed at the tip of the needle 13 has an injection hole 15 in the inner case 14. It corresponds to the valve seat 14a around the. A plate-shaped jet flow adjusting plate 41 is fixed to the tip surface of the inner case 14 in a superposed state, and a total of four orifice holes 42 (two pieces) are provided in the jet flow adjusting plate 41 so as to be located inside the injection holes 15. (Only shown) is punched by a press.

In the fuel injection valve constructed as described above, when the needle 13 moves in the axial direction due to the excitation of the coil (not shown), the valve body 13a comes into contact with and separates from the valve seat 14a to open and close the injection hole 15, The fuel introduced into the inner case 14 is intermittently injected into the intake manifold of the engine through the injection hole 15 and the orifice hole 42 of the jet flow adjusting plate 41. And the orifice hole 4 at this time
The reference numeral 2 serves to guide the fuel passing through the inside thereof, adjust the injection direction and the injection angle (spread of the jet flow) to realize a predetermined spray shape, and adjust the injection amount to a predetermined value.

However, this conventional jet flow adjusting plate 41
However, since the orifice hole 42 is simply punched, the openings at both ends thereof both form corners of about 90 °. Therefore, the flow of the fuel introduced from the injection hole 15 into the orifice hole 42 is disturbed at the opening on the upstream side (the injection hole 15 side), and the substantial length for guiding the fuel in the orifice hole 42 is short. In some cases, it was not possible to achieve a predetermined spray shape and injection amount. Since the plate thickness of the jet flow adjusting plate 41 is limited to about 0.2 to 0.3 mm from the viewpoint of the punch life at the time of punching, the total length of the orifice hole 42 is naturally limited and extension is difficult. It was

Therefore, in order to eliminate such a problem,
For example, a jet flow adjusting plate for a fuel injection valve described in JP-A-2-241975 has been proposed.

The jet flow adjusting plate has a single orifice hole in the center, and a quadrangular pyramid-shaped chamfered portion that opens upward is formed at the opening on the upstream side of the orifice hole.
Therefore, the fuel injected from the injection hole is guided to the chamfered portion and introduced into the orifice hole without causing turbulence, and the fuel is guided by utilizing the entire length of the orifice hole. In other words, although the entire length of the orifice hole is shortened by forming the chamfered portion, the substantial fuel guiding action is increased on the contrary, so that a predetermined spray shape and injection amount can be realized.

[0009]

The jet flow adjusting plate of the fuel injection valve described in the prior art publication has a structure for realizing a predetermined spray shape and injection amount as described above, but its surface No mention is made of a specific method of forming the lead portion. However, since the orifice hole has an extremely small diameter, precise centering work is required to form the chamfered portion in the opening. In the jet adjusting plate of the publication, the orifice hole is located at the center, so that the orifice hole can be centered on the basis of the outer circumference of the jet adjusting plate. However, in the jet adjusting plate 41 of FIG. 6, each orifice hole 42 is eccentric. Since the particles are dispersed, the centering work is difficult, and it is impossible to realize this type of jet adjusting plate 41.

Therefore, according to the first aspect of the present invention, the plurality of orifice holes having the chamfered portions formed in the openings exert a sufficient guide function for fuel, and an ideal spray shape and an accurate injection amount can be realized. It is an object to provide a jet flow adjusting plate for a fuel injection valve.

A second aspect of the present invention is a method of manufacturing a jet flow adjusting plate of a fuel injection valve, which is capable of easily forming a chamfered portion at the opening of the orifice hole and thus easily manufacturing the jet flow adjusting plate of the first aspect. Is the challenge.

[0012]

A jet flow adjusting plate for a fuel injection valve according to a first aspect of the present invention is arranged downstream of an injection hole of a fuel injection valve provided in an intake passage of an engine and is used for moving a valve body. In a jet flow adjusting plate of a fuel injection valve that adjusts the spray shape and injection amount of the fuel injected from the injection hole into the intake passage with it, the jet adjusting plate penetrates the jet flow adjusting plate and is centered on the axial center of the valve body. And a plurality of orifice holes inclined at a predetermined angle with respect to the axial center, and the orifices of the orifice holes are formed with the axial center aligned with each other. And a chamfer having a cone shape that expands.

According to a second aspect of the present invention, there is provided a method for manufacturing a jet flow adjusting plate for a fuel injection valve, wherein the jet flow adjusting plate set on the die is punched at a predetermined angle with a punch, and the punching portion formed on the punch tilts the jet flow adjusting plate at a predetermined angle. The orifice hole forming step of penetrating the orifice hole, and the punch is further moved to press the press-fitting portion formed on the base end side of the punching portion into the orifice hole so that the axial center of the opening of the orifice hole is formed. And a chamfered portion forming step of forming the same chamfered portion.

[0014]

According to the first aspect of the invention, the fuel injected from the injection hole along with the movement of the valve body is guided to the chamfered portion and introduced into each orifice hole without causing any disturbance. The fuel is guided by utilizing the entire length of, and the spray shape and the injection amount according to the settings of the inclination angle and the inner diameter of the orifice hole are obtained.

According to another aspect of the present invention, the jet adjusting plate is punched at a predetermined angle by the punch in the orifice hole forming step,
The punching part of the punch penetrates the orifice hole,
The punch further moves in the chamfer forming step, and the opening of the orifice hole is plastically deformed by press-fitting of the press-fitting portion of the punch to form the chamfer. Since the chamfered portion is formed at the same time when the orifice holes are punched in the jet adjusting plate in this way, it is difficult to perform centering work because a plurality of orifice holes are dispersedly arranged in the jet adjusting plate. However, the chamfered portion can be formed extremely easily by punching the individual orifice holes once.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A jet flow adjusting plate for a fuel injection valve and a method of manufacturing the same according to an embodiment of the present invention will be described below.

FIG. 1 is a sectional view showing a fuel injection valve using a jet flow adjusting plate according to an embodiment of the present invention.

First, the schematic structure and operation of the fuel injection valve provided with the jet flow adjusting plate 1 of this embodiment will be described. This fuel injection valve is provided in an intake manifold of an engine (not shown) and is exposed in the manifold. It plays a role of injecting fuel from the tip side (lower side in the figure) to supply it to the engine. A stator 11 is built in at the base end side (upper side in the drawing) of the fuel injection valve, and an armature 12 is arranged at the tip end side of the stator 11 so as to be slightly movable in the axial center C1 direction. The needle 13 welded and fixed to the tip side of the armature 12 extends along the axis C1 and the tip side is inserted into the inner case 14, and the valve body 13a formed at the tip of the needle 13 is inside the inner case 14. Corresponds to the valve seat 14a around the injection hole 15.
Needle 13 is spring 1 through armature 12
6 is urged toward the tip side, and the valve element 13a is moved to the valve seat 14
The injection hole 15 of the inner case 14 is closed by pressure contact with a. The biasing force of the spring 16 is adjusted by the adjusting rod 17.

A coil 18 is wound around the outer periphery of the stator 11, and the coil 18 is connected to a control circuit (not shown) via a terminal 19 by a signal line and is excited in accordance with a control signal from the control circuit. . With the excitation of the coil 18, the stator 11 attracts the armature 12 against the biasing force of the spring 16, and the needle 13 moves to the base end side together with the armature 12 until the stop ring 20 restricts the valve body 13a. Is separated from the valve seat 14a to open the injection hole 15. Then, the control circuit repeats the excitation of the coil 18 in synchronism with the rotation of the engine, and the injection hole 15 is opened / closed accordingly, so that the fuel having a constant pressure introduced into the inner case 14 is intermittent at a predetermined timing. Is injected from the injection hole 15.

A disc-shaped jet adjusting plate 1 having a plate thickness of about 0.2 to 0.3 mm is welded in a superposed state to the front end surface of the inner case 14, and a mounting cap 21 having an escape hole 21a in the center thereof is provided. It is installed. The jet flow adjusting plate 1 is provided with a total of four orifice holes 2a and 2b, and the fuel injected from the injection holes 15 is used for the orifice holes 2a and 2b as will be described later.
The spray shape and the injection amount are adjusted by a and 2b.

Next, the details of the jet flow adjusting plate 1 will be described.

FIG. 2 is an enlarged sectional view showing a jet flow adjusting plate of a fuel injection valve according to an embodiment of the present invention, and FIG. 3 is a jet flow adjusting plate of a fuel injection valve according to an embodiment of the present invention shown in FIG. FIG. 4 is a view as viewed from the direction of arrow A, and FIG. 4 is an explanatory view showing a punching procedure of the orifice hole of the jet flow adjusting plate of the fuel injection valve according to the embodiment of the present invention.

The engine of this embodiment is provided with a four-valve type valve operating mechanism, and although not shown, two intake valves are provided for each cylinder in the intake manifold. Each of the orifice holes 2a and 2b has a circular shape with an inner diameter of 0.2 mm, and the orifice holes 2a and 2b are arranged in the injection hole 15 on a circle centered on the axis C1 at equal intervals of 90 °. The inner diameter of the orifice holes 2a and 2b is the required injection amount 1 of the fuel injection valve.
It is set to satisfy the range of 00 to 300 cc / min. The two orifice holes 2a on one side have a shaft center C1 toward the front end side.
The two orifice holes 2b on the other side are inclined at an inclination angle α in a direction further away from each other, and the two orifice holes 2b on the other side are inclined in the opposite direction with respect to the axial center C1 with respect to the orifice hole 2a. Is tilted at and is directed to the other intake valve. As is clear from FIG. 3, the orifice holes 2a and 2b in the same group are inclined in the same direction.

On the injection hole 15 side of each orifice hole 2a, 2b,
That is, the chamfered portion 3 is formed in the opening on the upstream side coaxially with the axis C2 of the orifice holes 2a and 2b. The chamfered portion 3 has a conical shape that expands toward the injection hole 15 side, and its chamfer angle β
Is set to 15 °. Here, the depth of the chamfered portion 3 (the dimension of the jet flow adjusting plate 1 in the thickness direction) is set to 0.1 mm, that is, about 1/3 to 1/2 of the thickness of the jet flow adjusting plate 1.

The orifice holes 2a and 2b and the chamfered portion 3 of the jet flow adjusting plate 1 configured as described above are formed by punching with a press. As shown in FIG. 4A, this punching process is performed using a lower die 31 and an upper die 32 that hold the jet flow adjusting plate 1 and a punch 33 that punches the jet flow adjusting plate 1. A punching hole 31a and a guide hole 32a are coaxially formed in the lower die 31 and the upper die 32 at the same inclination angle α as the orifice holes 2a and 2b, and the punching hole 31a is the orifice hole 2 of the jet flow adjusting plate 1.
The inner diameter of the guide holes 31a is the same as that of a and 2b, and the inner diameter of the guide hole 31a is larger. The punch 33 is arranged in the guide hole 31a so as to be movable up and down, and a punching portion 33a is formed at a lower end of the punch 33 through a tapered press-fitting portion 33b. The outer diameter of the punched portion 33a corresponds to the inner diameter of the punched hole 31a of the lower die 31 with a predetermined clearance for punching, and the angle of the press-fitting portion 33b is set equal to the chamfer angle β of the chamfered portion 3. Has been done.

At the time of punching, as shown in FIG. 4 (a), the portions of the jet adjusting plate 1 where the orifice holes 2a and 2b are to be formed correspond to the punching holes 31a of the lower die 31, and the orifice holes 2a and 2a. The attitude of the jet adjusting plate 1 is adjusted around the axis of the punching hole 31a so that the 2b is punched at a predetermined inclination angle α, and then the jet adjusting plate 1 is held by the lower die 31 and the upper die 32. Then, when the punch 33 is started to be lowered by a press (not shown),
As shown in (b), first, the punch 3 is attached to the jet adjusting plate 1.
Orifice holes 2a and 2b are punched by the punching portion 33a of No. 3 (orifice hole forming step). When the punch 33 is further lowered, the press-fitting portion 33b is moved to the orifice hole 2a,
The orifice holes 2a and 2b are press-fitted into the 2b from above.
The upper opening is plastically deformed in correspondence with the press-fitting portion 33b, and the chamfered portion 3 is formed so as to coincide with the axis C2 of the orifice holes 2a and 2b (chamfered portion forming step). When the press reaches the maximum stroke, the depth of the chamfered portion 3 becomes about 1/3 to 1/2 of the thickness of the jet flow adjusting plate 1, and the orifice holes 2a,
The punching of 2b is completed. After that, the orifice holes 2a and 2b are sequentially punched out in the same procedure.

As described above, in this embodiment, when the orifice holes 2a and 2b are punched in the jet adjusting plate 1, the chamfered portion 3 is simultaneously formed by the press-fitting portion 33b formed in the punch 33. Therefore, even when the plurality of orifice holes 2a and 2b are dispersedly arranged in the jet flow adjusting plate 1 as in the present embodiment and the centering work is difficult, the punching is performed once for each of the orifice holes 2a and 2b. The chamfered portion 3 is extremely easily formed by working.

In the fuel injection valve using the jet flow adjusting plate 1, when the fuel is injected from the injection hole 15 in accordance with the excitation of the coil 18 as described above, as in the conventional example described in the publication, The fuel is guided to the chamfered portion 3 and introduced into the orifice holes 2a and 2b without causing any disturbance. Therefore, the fuel is guided by utilizing the entire length of the orifice holes 2a, 2b, so that the formation of the chamfered portion 3 shortens the overall length of the orifice holes 2a, 2b, but the substantial fuel guiding function is provided. On the contrary, the orifice holes 2a,
It is possible to obtain the spray shape and the injection amount according to the setting of the inclination angle α of 2b, the inner diameter, and the like.

FIG. 5 is an explanatory diagram comparing a spray shape of a fuel injection valve using a jet flow adjusting plate according to an embodiment of the present invention with a conventional example. Since the drawing shows the jet flow seen from the B direction in FIG. 3, only the jet angle (spread of the jet flow) is shown regardless of the jet direction.

Here, the spray shape (determined by the injection direction and the injection angle) and the injection amount required for the fuel injection valve differ depending on the engine specifications and the like, but in the present embodiment and the conventional example of FIG. In the fuel injection valve, the inner diameters of the orifice holes 2a and 2b, the arrangement state, and the like are set so as to reduce the injection angle as much as possible for the purpose of reducing the manifold wet. As is clear from the figure, the injection angle is 15 in the conventional example.
Although it is about 5 °, in the present embodiment, it is greatly reduced to about 5 °. Needless to say, this is a result of the chamfered portion 3 enhancing the guiding action of the orifice holes 2a and 2b.

As described above, the jet flow adjusting plate 1 of the fuel injection valve of this embodiment is arranged downstream of the injection hole 15 of the fuel injection valve provided in the intake manifold of the engine, and the valve body 1
In the jet adjusting plate 1 of the fuel injection valve that adjusts the spray shape and the injection amount of the fuel injected from the injection hole 15 into the intake manifold with the movement of 4a, the shaft is provided so as to penetrate the jet adjusting plate 1. Four orifice holes 2a, 2b are arranged equally on a circle centered on the center C1 and are inclined at an inclination angle α toward the tip side in a direction away from the axis C1.
And a conical chamfered portion 3 which is formed in the opening of each orifice hole 2a, 2b on the side of the injection hole 15 with the axis C2 coinciding with each other and expands toward the injection hole 15 at a chamfer angle β. It has and. This structure corresponds to the embodiment of the invention of claim 1.

Therefore, the fuel injected from the injection hole 15 is guided into the chamfered portion 3 and is introduced into the orifice holes 2a and 2b without causing any turbulence.
A sufficient fuel guiding action can be exerted by utilizing the entire length of a and 2b, and an ideal spray shape and injection amount according to the settings of the inclination angle α and the inner diameter of the orifice holes 2a and 2b can be obtained. Can be realized.

Further, in the method of manufacturing the jet flow adjusting plate 1 of the fuel injection valve of this embodiment, the jet flow adjusting plate 1 held by the lower die 31 and the upper die 32 is punched by the punch 33 at the inclination angle α, and the punch is performed. Orifice hole forming step of penetrating the orifice holes 2a and 2b having the inclination angle α by the punching portion 33a formed in 33, and the press-fitting portion 33b formed on the base end side of the punching portion 33a by further lowering the punch 33. Is press-fitted into the orifice holes 2a, 2b,
And a chamfered portion forming step of forming a chamfered portion 3 whose axis C2 coincides with the opening of 2b. This configuration is claim 2.
Of the present invention.

Therefore, since the chamfered portion 3 is formed at the same time when the orifice holes 2a and 2b are punched in the jet flow adjusting plate 1, the jet flow adjusting plate 1 has a plurality of orifice holes 2a and 2b.
Even when the centering work is difficult due to the distributed arrangement of the 2b, the chamfered portion 3 can be extremely easily formed by one punching process for each of the orifice holes 2a and 2b, and thus the jet flow of the present embodiment. The adjusting plate 1 can be easily manufactured.

By the way, although the chamfered portion 3 is formed in a conical shape in the above embodiment, the present invention is not limited to this, and the fuel injected from the injection hole 15 is not limited to this. It suffices as long as it can guide without disturbing 2a and 2b. Therefore, its shape is
Any shape may be used as long as it has a cone shape that widens to the 5 side, and may be formed in, for example, a triangular pyramid shape or a quadrangular pyramid shape.

In the above embodiment, a total of four orifice holes 2a and 2b are equally divided on a circle centered on the axis C1 of the needle 13, and two orifice holes 2a and 2b are inclined at an inclination angle of two. Although it was tilted in the opposite direction at α and directed to each intake valve, the present invention is not limited to this, and these settings are based on the engine specifications or the required spray shape. And can be arbitrarily changed according to the injection amount. Therefore, for example, the orifice hole 2
The number and inner diameter of a and 2b may be changed, and the inclination angle α may be changed.

[0037]

As described above, according to the jet flow adjusting plate of the fuel injection valve of the first aspect, the fuel injected from the injection hole along with the movement of the valve body is guided to the chamfered portion and is disturbed. Since it is introduced into each orifice hole without causing any problems, it is possible to utilize the entire length of the orifice hole to exert sufficient fuel guiding action, and it is possible to adjust the inclination angle and inner diameter of the orifice hole. It is possible to realize an ideal spray shape and injection amount.

According to the method of manufacturing the jet flow adjusting plate of the fuel injection valve of the present invention, since the chamfered portion is formed at the same time when the orifice hole is punched in the jet flow adjusting plate, a plurality of orifices are formed in the jet flow adjusting plate. 1 for each orifice hole, even if the holes are distributed and difficult to center
The chamfered portion can be formed extremely easily by a single punching process, and the jet adjusting plate according to claim 1 can be easily manufactured.

[Brief description of drawings]

FIG. 1 is a sectional view showing a fuel injection valve using a jet flow adjusting plate according to an embodiment of the present invention.

FIG. 2 is an enlarged cross-sectional view showing a jet flow adjusting plate of a fuel injection valve according to an embodiment of the present invention.

FIG. 3 is a view as seen from an arrow A in FIG. 2 showing a jet flow adjusting plate of the fuel injection valve which is an embodiment of the present invention.

FIG. 4 is an explanatory view showing a procedure for punching an orifice hole of a jet flow adjusting plate of a fuel injection valve according to an embodiment of the present invention.

FIG. 5 is an explanatory diagram comparing a spray shape of a fuel injection valve using a jet flow adjusting plate according to an embodiment of the present invention with a conventional example.

FIG. 6 is an enlarged sectional view showing a jet flow adjusting plate of a conventional fuel injection valve.

[Explanation of symbols]

 1 Jet Flow Adjusting Plates 2a, 2b Orifice Hole 3 Chamfering Section 13a Valve Body 15 Injection Hole 31 Lower Die 32 Upper Die 33 Punch 33a Punching Section 33b Press-fitting Section

Claims (2)

[Claims] 1. A spray shape of fuel which is disposed downstream of an injection hole of a fuel injection valve provided in an intake passage of an engine and is injected from the injection hole into the intake passage as the valve element moves, and In a jet flow adjusting plate of a fuel injection valve for adjusting an injection amount, the jet flow adjusting plate penetrates through the jet flow adjusting plate, is distributed around the axis of the valve element, and is inclined at a predetermined angle with respect to the axis. A plurality of orifice holes, and a chamfered portion in the shape of a cone that is formed so that the axial center of the orifice holes coincides with the openings of the orifice holes and that expands toward the nozzle holes. And a jet flow adjustment plate for the fuel injection valve. 2. An orifice hole forming step of punching a jet flow adjusting plate set on a die with a punch at a predetermined angle, and forming an orifice hole inclined at a predetermined angle by a punching portion formed in the punch; Is further moved to press the press-fitting portion formed on the base end side of the punching portion into the orifice hole to form a chamfered portion having a chamfered portion having an axial center aligned with the opening of the orifice hole. A method of manufacturing a jet flow adjusting plate for a fuel injection valve, comprising: