WO2005090775A1

WO2005090775A1 - Fuel injection rail

Info

Publication number: WO2005090775A1
Application number: PCT/JP2005/003884
Authority: WO
Inventors: Akira Yamakabe; Yasuhiro Yaguchi
Original assignee: Sanoh Kogyo Kabushiki Kaisha
Priority date: 2004-03-23
Filing date: 2005-03-07
Publication date: 2005-09-29
Also published as: JP2005273475A

Abstract

A fuel injection rail having a shape suitable to be joined by laser welding and not by brazing. A body case (20) is constructed from a first case member (22a), a case with the bottom, and a plate-like second case member (22b) closing an opening of the first case member (22a). On either the first case member (22a) or the second case member (22b) is formed a flange section (26) superposed by the other, and the portion where the flange section (26) and the other are superposed is joined by laser welding.

Description

Fueno Rain Jet Lenore

Technical field

The present invention relates to a fuel injection rail used for a fuel injection device supply unit in an automobile engine.

Background art

[0002] In a fuel supply system that supplies fuel to an automobile engine, fuel is sent from a pump to a fuel injection rail through a fuel supply pipe, and is attached to the fuel injection rail to distribute the fuel to the injectors. Each of the hawks is sprayed into the engine intake hold.

FIG. 9 shows a conventional fuel injection rail. FIG. 10 is a cross-sectional view of the fuel injection rail of FIG. The main body of the fuel injection rail is composed of an upper case 10a and a lower case 10b. A plurality of injector cups 12 for mounting the injectors are arranged at predetermined intervals on the bottom surface of the lower case 10b. A fuel supply pipe 14 is connected to the center of the upper surface of the upper case 10a.

[0004] Both the upper case 10a and the lower case 10b are formed by pressing a sheet metal material by pressing. The lower case 10b and the upper case 10a are integrally joined by brazing. The brazing method is a method in which a solder having a melting point lower than that of a base material is poured into a gap between melted base material joints to solidify the solder. This brazing method is a joining method suitable for joining small and complex parts.

[0005] In the case of a fuel injection rail, the compatibility between the solder and the steel material of the base material is good, and there is an advantage that it can be joined airtightly by the solder melted in the gap.

Disclosure of the invention

Problems to be solved by the invention

[0006] However, in the case of joining by brazing, the upper case 10a and the lower case 10b are It is important to manage the gaps that are created when fitted. If the gap is not uniform or the gap is too large, the wax flows out and causes poor bonding due to the withdrawal of the wax, resulting in an airtight connection. For this reason, strict dimensional control is required for the press forming of the upper case 10a and the lower case 10b.

[0007] In addition, the residual stress may be released at a high temperature in the brazing process, and the main body may be deformed. Therefore, the height and angle of the injector cup may be outside the specified dimensional tolerances. As a result of inspection, if the height or mounting angle of the indicator cup is out of tolerance, it will be necessary to modify it by changing a part of the main body.

[0008] Further, when stainless steel is used as a material for improving the corrosion resistance, there is a drawback that the structure becomes sensitized by the reaction with the wax and the corrosion resistance is lowered.

[0009] On the other hand, joining methods other than brazing, for example, welding methods such as resistance welding and laser welding, in the case of a fuel injection rail, are actually applied because the shape is complicated for small items. The current situation is not.

Accordingly, an object of the present invention is to provide a fuel injection rail having a shape suitable for joining by laser welding without solving the problems of the prior art and without using brazing.

Means for solving the problem

[0010] In order to achieve the above object, the present invention provides a fuel injection rail formed by joining a case member, an injector cup, and other members constituting a main case of the fuel injection rail by laser welding. A first case member comprising a bottom case and a plate-like second case member that closes the opening of the first case member constitute a main body case, and the first case member and the _second case member Of these, a flange portion that overlaps the other is formed on one side, and the overlapping portion with the flange portion is joined by laser welding.

[0011] According to the present invention, since it has a structure suitable for laser welding in which the heating region can be locally limited by a laser beam having a high energy density, the case body is subject to thermal deformation in a conventional heating furnace. Compared to brazing, the amount of gaps in the overlapped part of the case parts need not be precisely controlled. Brief Description of Drawings

FIG. 1 is a side view showing a fuel injection rail according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view of the fuel injection rail A—A in FIG.

FIG. 3 is a view showing a cross section of a joint portion formed by laser welding in the fuel injection rail according to the first embodiment of the present invention.

FIG. 4 is a cross-sectional view showing a fuel injection rail according to a second embodiment of the present invention.

FIG. 5 is a cross-sectional view showing a fuel injection rail according to a third embodiment of the present invention.

FIG. 6 is a cross-sectional view showing a fuel injection rail according to a fourth embodiment of the present invention.

FIG. 7 is a cross-sectional view showing another example of the fuel injection rail according to the fourth embodiment of the present invention.

FIG. 8 is a cross-sectional view showing a fuel injection rail according to a fifth embodiment of the present invention.

FIG. 9 is a side view showing a conventional fuel injection rail.

FIG. 10 is a cross sectional view showing a conventional fuel injection rail.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, an embodiment of a fuel injection rail according to the present invention will be described with reference to the accompanying drawings. FIG. 1 shows a fuel injection rail according to a first embodiment of the present invention. In FIG. 1, reference numeral 20 indicates a fuel injection rail body case. The body case 20 of the fuel injection rail also includes two case member caps, a first case member 22a and a second case member 22b.

[0014] In this embodiment, both the first case member 22a and the second case member 22b are processed by press-molding a stainless steel plate as a raw material. Of these, the first case member 22a has a long and narrow shape. It is drawn to the shape of the bottom case. The second case member 22b is the first case part An elongated, plate-like member that covers the opening of the material 22a is used.

[0015] An injector cup 24 for mounting the injector is attached to the bottom surface of the first case member 22a. Four injector cups 24 are arranged at predetermined intervals. A fuel supply pipe 25 that guides fuel is connected to the center of the second case member 22b.

[0016] The first case member 22a and the second case member 22b do not have a joint portion by brazing as in the conventional case, and have a structure in which all parts can be easily joined by laser welding. Has been improved.

FIG. 3 is a cross-sectional view (FIG. 3 (a)) of the joint portion between the first case member 22 a and the second case member 22 b in the fuel injection rail of the present embodiment, and the first case member 22 a and the injector cup 24. FIG. 3B shows a cross section of the joint between the second case member 22b and the end of the fuel supply pipe 25 (FIG. 3C).

As shown in FIG. 3 (a), a flange portion 26 is formed on the periphery of the opening of the first case member 22a of the first case member 22a and the second case member 22b. The flange portion 26 is overlapped in the same direction as the peripheral portion of the second case member 22b.

Next, as shown in FIG. 3 (b), a cylindrical burring wall 27 rising inward is formed at the bottom of the first case member 22a by the burring force g. Yes. On the other hand, a cylindrical mounting portion 28 is formed in the bell-shaped injector cup 24, and this mounting portion 28 is adapted to be fitted into the knurling wall 27 without a gap.

Furthermore, as shown in FIG. 3 (c), the second case member 22b is connected to the terminal of the fuel supply pipe 25 to form a cylindrical shape that rises outward by a burring cage. A burring wall 29 is formed, and the terminal of the fuel supply pipe 25 is fitted into the burring wall 29 without any gaps.

[0021] According to the fuel instruction rail of the present embodiment configured as described above, the laser welding in the temporary assembly and assembly is easy in the following points.

When the second case member 22b is placed on the first case member 22a, the flange portion 26 of the first case member 22a and the peripheral portion of the second case member 22b overlap each other without a gap. To laser weld the first case member 22a and the second case member 22b, the laser welding machine The laser beam can be irradiated along the flange portion 26 while moving the torch, and the overlapping portion with the flange portion 26 can be melted and joined by the laser beam.

Similarly, the injector cup 24 may also be welded while moving the laser beam in the circumferential direction with the mounting portion 28 fitted to the burring wall 27. Fuel supply pipe

As for 25, laser welding can be performed in the same manner with the end fitted to the burring wall 29.

[0023] The laser beam has a high energy density and can locally limit the heating region, so that thermal deformation can be significantly reduced compared to brazing in a conventional heating furnace.

[0024] Further, since the fuel injection rail requires airtightness, when brazing the first case member 22a and the second case member 22b, the gap management of the overlapped portion where both are fitted is precisely controlled. There was a need to do. On the other hand, in the present embodiment, since it is not necessary to adjust the gap of the welded portion by simply overlapping the second case member 22b on the first case member 22a, the first case member 22a and the second case member 22a It is not necessary to use a precise die for press-molding the case member 22b, which leads to a reduction in manufacturing costs. Next, a fuel injection rail according to a second embodiment of the present invention will be described with reference to FIG.

The second embodiment is different from the first embodiment in that an inclined step 30 is provided in the overlapping portion of the flange portion 26 between the first case member 22a and the second case member 22b. This is a point that the shoulder portion 31 of the partial force injector cup 24 is formed by fitting the injector cup 24 to the burring wall 27 and performing laser welding. Other structures are the same as those of the first embodiment, and the same components are denoted by the same reference numerals and description thereof is omitted.

[0025] According to the second embodiment configured as described above, an inclined step 30 is provided at the overlapping portion of the flange portion 26 between the first case member 22a and the second case member 22b. Therefore, when irradiating a laser beam with a direct upward force, even if there is a slight shift in the irradiation position of the laser beam, it is possible to absorb the positional shift at the step 30 and prevent the melting from being hindered. [0026] Third Embodiment

FIG. 5 is a view showing a fuel injection rail according to a third embodiment of the present invention.

In the third embodiment, the portion where the injector cup 24 is laser-welded is the flare end 32 of the injector cup 24. The first case member 22a is formed with a mounting hole 33 for mounting the radiator cup 24, and the overlapping portion of the opening edge of the mounting hole 33 and the flared end 32 of the injector cup 24 is welded by laser welding. . Except this point, the second embodiment is the same as the second embodiment in FIG.

[0027] Fourth Embodiment

Next, a fuel injection rail according to a fourth embodiment of the present invention will be described with reference to FIGS.

In the first to third embodiments described so far, the first case member 22a to which the injector cup 24 is attached is the bottomed case, and the second case member 22b to which the fuel supply pipe 25 is connected is used. In the fourth embodiment, the first case member 40a is a plate-like member, and the second case member 40b is a bottomed case. This is an embodiment in which the relation between the plate member and the plate member is reversed.

In FIG. 6, a flange portion 42 is formed on the outer peripheral portion of the first case member 40a so as to overlap in the same direction as the peripheral portion of the second case member 40b. The first case member 40a has a mounting hole 44 for mounting the injector cup 24. The overlapping portion of the opening edge of the mounting hole 44 and the flared end 32 of the injector cup 24 is formed by laser welding. Welded.

[0029] On the other hand, in the fuel injection rail shown in FIG. 7, the first case in which the injector cup 24 is preliminarily molded by drawing so that it is not necessary to weld the injector cup 24. Member 40a is used. The first embodiment is similar to the embodiment of FIG. 6 in that a flange 42 is formed on the outer periphery of the first case member 40a.

[0030] Fifth Embodiment

Next, a fuel injection rail according to a fifth embodiment of the present invention will be described with reference to FIG. The fuel injection rail according to the fifth embodiment is based on the fourth embodiment shown in FIG. 6 and has a sealed chamber having a damper surface that absorbs pulsation associated with the opening / closing operation of the injector. It is a form.

[0031] In the fifth embodiment, the first sealed chamber 50, the second sealed chamber 51 on the side surface, and the fuel supply pipe 2

A total of three chambers are formed, with a third sealed chamber 52 through which 5 penetrates. These sealed chambers 50, 51

, 52 are joined by laser welding rectangular dish-shaped damper members 53, 54, 55 to the wall surface of the second case member 40b.

[0032] The same members are used for the damper members 53 and 54 that partition the first sealed chamber 50 and the second sealed chamber 51. In this case, the peripheral portions of the damper members 53 and 54 are used so that laser welding is easy. Are formed with flange portions 53a and 54a, respectively. Similarly, a flange portion 55a is also formed at the peripheral portion of the damper member 55 that partitions the third sealed chamber.

[0033] When such a damper member 53, 54, 55 is laser welded to the wall surface of the second case member 22b, a laser beam is irradiated from the torch to melt the base material, and the flange portions 53a, 54a, 55a are attached. Can be welded to the wall.

[0034] When the damper members 53, 54, 55 are brazed in the same manner, the entire instruction rail becomes hot, and there is a greater risk of the air contained in the flange members 53, 54, 55 expanding and bursting. It is not possible to braze the damper members 53, 54, 55 that partition the sealed chambers 50, 51, 52.

In this respect, in the present embodiment, the damper members 53, 54, and 55 can be joined by laser welding, so that the region to be heated can be limited to the local region of the flange portions 53a, 54a, and 55a. The air confined in 54 and 55 does not expand and burst.

Claims

The scope of the claims

[1] In a fuel injection train that is formed by joining a case member, an radiator cup, and other members constituting the main body case of the fuel injection rail by laser welding.

A first case member having a bottomed case force, a plate-like second case member that closes the opening of the first case member, and a force main body case.

A flange portion that overlaps the other of the first case member and the second case member is formed on one side,

The overlapping part with the flange part was joined by laser welding

This is a fuel injection rail.

[2] A step is provided at an overlapping portion of the flange portion of the first case member and the second case member.

The fuel injection rail according to claim 1, wherein:

[3] A burring wall that rises inward to attach the injector cup is formed at the bottom of the first case member, and the injector cup is joined to the burring wall by laser welding.

The fuel injection rail according to claim 1, wherein the fuel injection rail is provided.

[4] A mounting hole for mounting the injector cup is formed at the bottom of the first case member, and an overlapping portion of the opening edge of the mounting hole and the flare end of the injector cup is joined by laser welding. Become

[5] A mounting hole for mounting the injector cup is formed in the bottom of the second case member, and an overlapping portion of the opening edge of the mounting hole and the flare end of the injector cup is joined by laser welding. Become

[6] Of the first case member and the second case member, on the side where the injector cup is not attached, a burring wall rising toward the outside for attaching the fuel supply pipe is formed, and this burring wall The end of the fuel supply pipe is joined by laser welding. Become

The fuel injection rail according to claim 1, wherein the fuel injection rail is provided. A sealed chamber having a damper surface that absorbs pulsation is defined inside the first case member.