JP2003120473A - Manufacturing method of nozzle or orifice plate of liquid injection valve, nozzle or orifice plate of liquid injection valve, and fuel injection valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To press a nozzle part of an injector. SOLUTION: In a manufacturing method of a nozzle having an orifice to measure the liquid or an orifice plate, an inlet side hole and an outlet side hole of the orifice are constituted of holes having the shearing surface. In the manufacturing method of the nozzle and the orifice plate formed of holes having a connecting face of both holes, the holes are pressed from the orifice outlet side in a first step. A seat part is transferred from the orifice inlet side in a second step. Punching is performed from the orifice inlet side in a third step. The productivity is improved thereby, and the fuel is metered with high accuracy.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a nozzle or an orifice plate for injecting a fluid, a method for manufacturing a nozzle or an orifice plate having an orifice for measuring a flow rate, and a fuel injection valve using the same.

[0002]

2. Description of the Related Art Conventionally, as a method of processing an orifice in manufacturing a nozzle or an orifice plate, Japanese Patent Laid-Open No.
1-96196, there is a method of extruding from the orifice outlet side with a punch having substantially the same type as the orifice and then removing the extruded portion by machining.

[0003]

However, since the orifice inlet side has an important shape for measuring the flow rate, the above conventional technique requires deburring on the orifice inlet side after machining. Burrs generated by machining have variations in height and shape, and during deburring, these variations cause the state after deburring, that is, the orifice inlet shape, to be unstable. Therefore, the measurement accuracy of the orifice is not stable.

Since the fuel injection valve for in-cylinder injection of gasoline is required to have high performance in terms of injection amount and homogeneity of spray, it is necessary to improve the accuracy of the nozzle.

The orifice inlet shape is an important factor that determines the injection amount, and the orifice outlet shape is an important factor that determines the injection shape that determines the homogeneity of the injection. It is necessary to stabilize these shapes. .

[0006] Further, as another high-precision processing method, there is a grinding process or the like, but since the processing time is long and the cost is high, the productivity cannot be improved.

It is an object of the present invention to process a nozzle or orifice plate which can stabilize the inlet and outlet shapes of the orifice with high accuracy and has high productivity, and a nozzle or orifice plate with high accuracy of fluid metering, and It is to provide a fuel injection valve equipped with it.

[0008]

In order to achieve the above object, a nozzle or orifice plate according to the present invention is provided with holes whose inner surface is a shear surface on the inlet side and the outlet side of the orifice, and is broken between them. A metering orifice hole having a cross section.

According to another aspect of the invention, a first step of forming a hole by punching a hole downstream of the orifice to form a hole, a second step of transferring and forming a sheet portion by a sheet surface shape punch upstream of the orifice, and an intermediate step are performed. In the third step of punching out the plate portion with a punch, a nozzle or orifice plate is formed.

The sheet portion formed by plastic working as described above,
And a nozzle or orifice plate whose inlet and outlet sides are sheared surfaces. In another invention, a spray injection valve provided with such a nozzle or orifice plate is provided.

[0011]

Embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a vertical sectional view of an electromagnetic fuel injection valve for a gasoline engine of an automobile in which the present invention is implemented.

The magnetic circuit comprises a core 41, a yoke 42 and a movable valve 43, and a spring 44 for pressing a movable valve 43 having a valve seat 43a at its tip inside the core 41 against a valve seat portion 10c of the nozzle portion 10. An adjuster 45 that adjusts the load of the spring 44, a stopper 46 that becomes the stroke end of the movable valve 43, a swirler 12 that gives a swirling force to the fuel, a plate 13 that fixes the swirler 12 to the nozzle portion 10, a core 41 and a yoke 42. Ring 4 to prevent fuel from leaking between and to support the dry coil structure
7, a coil 48 for exciting the magnetic circuit, and a terminal bobbin 49 for energizing the coil 48.

In this injection valve, when the coil 48 is energized, the movable valve 43 moves in the direction of the core 41 against the biasing force of the spring 44, and the fuel is fed to the core 41, the adjuster 45, the ring 47, and the movable valve 43b. , 43c, the nozzle 10b, and the passage 13b of the plate, a swirling force is applied by the swirler groove 12b, and the liquid is ejected from the orifice 11. On the other hand, when the current of the coil 48 is cut off, the movable valve 43 comes into contact with the valve seat portion 10c by the force of the spring 44, and the valve is closed.

The nozzle portion 10, the orifice 11 and the valve seat portion 10c of the fuel injection valve body 1 having the above-described structure are particularly applicable to the present invention. The manufacturing method will be described below.

FIG. 2 is a partial longitudinal sectional view showing a manufacturing process of the nozzle portion 10 and the valve seat portion 10c of the fuel injection valve shown in FIG. 3, which is an embodiment of the present invention.

(I) shows the orifice 11 of the nozzle portion 10 and the blank shape before processing the valve seat portion 10c,
With the nozzle portion 10 set on the die 21 as in (II), the orifice 11 is half-punched with the cutting blade portion 20a of the punch 20 from the downstream side of the nozzle portion 10 by the pressing device, and finally the orifice 11 is formed. The surface to be used is formed by all shear surfaces with high accuracy.

Next, the valve seat portion 10c is transfer molded by the seat portion forming punch 23. At this time, the mandrel 22 is applied to the orifice 11 which has been subjected to the half blanking process in the previous step.

As a result, the molded material plastically flows toward the outlet side of the orifice, so that the length of the orifice can be increased by the amount of the flowing material.

Next, as shown in (IV), the orifice 11 is punched by the cutting blade portion 24a of the punching punch 24. The cutting blade portion 24a of the punch used at this time has a smaller diameter than the cutting blade portion 20a of the punch used in the half blanking process.

In order to further improve the durability of the nozzle portion 10, the nozzle portion 10 is quenched, and the valve seat portion 10c is finished by a hitting process after quenching.

Through the above steps, as shown in FIG. 3, it is possible to manufacture a nozzle having an orifice having a fractured surface and a seat portion, the upstream side and the downstream side of which are constituted by sheared surfaces.

Therefore, according to the nozzle manufacturing method of this embodiment, it is possible to manufacture a nozzle with high precision and high quality without lowering the productivity due to plastic working.

At this time, it is possible to obtain an orifice having no step by making the size of the cutting edge 20a of the punch 20 equal to the size of the cutting edge 24a of the punch 24.

Since the orifice inlet is a shear surface,
Weighing accuracy can be stabilized.

Moreover, since the orifice outlet side is a sheared surface, the spray can be stabilized.

Furthermore, (orifice length) / (orifice diameter) = 2.4 can be realized.

This embodiment is also effective in manufacturing an orifice plate as shown in FIG.

[0029]

According to the present invention, since the upstream side hole and the downstream side hole of the orifice are machined with sheared surfaces, a highly accurate nozzle or orifice plate with stable shape accuracy can be obtained. Further, in another invention, since sheet formation can be performed at the same time, productivity can be increased. Further, if the fuel injection valve is configured by using such a nozzle or orifice plate, the fuel metering accuracy is improved.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of an electromagnetic fuel injection valve of the present invention.

FIG. 2 is a partial sectional view showing an embodiment of the nozzle of the present invention.

FIG. 3 is a diagram illustrating a manufacturing process of the nozzle of the present invention.

FIG. 4 is a partial sectional view showing an embodiment of the orifice plate of the present invention.

[Explanation of symbols]

Reference numeral 10 ... Nozzle portion, 10c ... Valve seat portion, 11 ... Injection port (orifice), 11a ... First shear surface, 11b ... Second shear surface, 11c ... Broken surface, 30 ... Orifice plate.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Kenichi Gunji             2477 Takaba, Hitachinaka City, Ibaraki Prefecture Stock Association             Inside Hitachi Car Engineering (72) Inventor Keiji Kawahara             Hitachinaka City, Ibaraki Prefecture 2520 Takaba             Ceremony Company Hitachi Ltd. Automotive equipment group F-term (reference) 3G066 AB02 BA51 BA55 CC06U                       CC14 CC21 CC43 CE22                 4F033 AA13 BA03 CA01 DA01 EA01                       KA02 MA00 NA01

Claims (8)

[Claims] 1. A method of manufacturing a nozzle or orifice plate having an orifice for measuring a fluid, wherein an inlet side hole and an outlet side hole of the orifice are constituted by holes having a shear surface of a press, and have a connecting surface of both holes. A nozzle and an orifice plate, which are formed by holes. 2. The nozzle or orifice plate according to claim 1, wherein the orifice has at least two kinds of holes having different diameters. 3. A nozzle and an orifice plate according to claim 1 or 2, wherein the longitudinal dimension of the orifice inlet side hole and the longitudinal dimension of the orifice outlet side hole are different. 4. The nozzle according to claim 1, wherein a conical seat portion is provided at a starting end of the orifice inlet side hole to face a movable valve and to provide a sealing function between the movable valve and the movable valve. Or an orifice plate. 5. A method of manufacturing a fuel injection valve having a fuel injection orifice at the tip of a nozzle portion, wherein a first blanking process is performed on a nozzle blank from the outlet side of the orifice with a punch having substantially the same diameter as the orifice. A second step of pressing the center of the upper surface of the nozzle material from the orifice inlet side with a sheet surface shape punch to transfer-form a substantially conical sheet portion by plastic flow; and the sheet on the orifice inlet side. A method for manufacturing a nozzle or an orifice plate, characterized in that punching is performed from the bottom surface of the portion with a punch having a diameter smaller than that used in the half blanking, and the orifice is formed by a third step of penetrating the hole. 6. A method of manufacturing a fuel injection valve having a fuel injection orifice at the tip of a nozzle portion, wherein the upper surface center of the nozzle material is pressed from the orifice inlet side by a sheet surface shape punch, and a substantially conical shape is formed by plastic flow. Used in the first step of transferring and molding a sheet-shaped sheet portion, the second step of performing a half blanking process from the sheet portion with a punch having a diameter substantially the same as that of the orifice, and the half blanking process from the orifice outlet side. A method for manufacturing a nozzle, wherein punching is performed with a punch having a diameter smaller than that of the nozzle, and an orifice is formed by a third step of penetrating a hole. 7. A method of manufacturing a nozzle or orifice plate having an orifice for measuring a fluid, wherein a half blanking process is performed on a nozzle blank from the outlet side of the orifice with a punch having substantially the same diameter as that of the orifice, and a hole formed thereby. Insert the mandrel into the hole, press the center of the upper surface of the nozzle material from the orifice inlet side with the sheet surface shape punch while maintaining the accuracy of the inner diameter of the hole, and transfer molding the sheet portion by plastic flow A method for manufacturing a nozzle or an orifice plate, characterized in that the orifice length is increased by flowing the material toward the outlet side and flowing the material. 8. A seat portion that opens and closes a fuel passage in cooperation with a valve body, a first hole formed on the downstream side of the seat portion with a shear surface, and a downstream side of this hole. A fuel injection valve having a metering orifice formed by the connecting surface formed and a second hole formed on the downstream side of the orifice by a shearing surface on the inner circumference.