JPH0729251Y2 - Fuel delivery pipe - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a fuel injection device for a fuel injection type automobile engine, in which fuel supplied from a fuel pressure pump is supplied to each intake passage or each cylinder of the engine. It relates to an improvement of a fuel delivery pipe for supplying through a fuel injection nozzle.

(Prior Art) A typical structure of a fuel delivery pipe used in an in-line four-cylinder engine is shown in FIG. In this fuel delivery pipe 10, a main pipe 1 having a rectangular cross section extends along the crankshaft direction, fuel is supplied from a fuel supply pipe 2 connected to one end of the main pipe 1, and is connected to the other end of the main pipe 1. Fuel is returned from the fuel return pipe 3. Four sockets 4 for receiving the tip of the injection nozzle are attached to the bottom surface of the main pipe 1 at a predetermined angle. These sockets must be matched at an exact angle to the mounting direction of each injection nozzle of the cylinder of four cylinders, and the pitch between the sockets must also be exactly the same as the pitch between the injection nozzles of the cylinder. I have to.

The main pipe 1 is further provided with two thick and solid brackets 5 for attaching the fuel delivery pipe to the engine body in a lateral direction.

As shown in FIG. 5, the fuel return side pipe 3 is often inserted and fixed directly to the side portion of the main pipe 1, while the fuel supply side pipe 2 is fixed to the main pipe by an annular adapter 6.
Often connected via (see FIG. 6). This is because the main pipe 1 has a rectangular cross section, so it is difficult to directly fix a pipe having a circular cross section to the end of the main pipe.

As another conventional example, in the example shown in FIG. 7, the fuel pipe 2 is shaped like an age joint 12, and a bolt 14 is screwed into a screw 13 engraved at the end of the main pipe 1 to fix the age joint 12. There is.

However, such a conventional mounting method has a drawback that the annular adapter 6 and the eye joint 12 are required, so that the number of parts is increased, the welding and assembling steps are required, and the cost is increased.

Japanese Utility Model Laid-Open No. 59-40577 discloses an example in which two fuel pipes are both connected to the side portion of a main pipe having a rectangular cross section. However, back pressure is applied to the pipe on the fuel supply side to supply fuel. Has the disadvantage that it decreases.

(Problems to be Solved by the Invention) An object of the present invention is to reduce the cost of the fuel delivery pipe by eliminating the manufacturing difficulty in the conventional technique and reducing the processing man-hour.

Another object of the present invention is to reduce the weight of the fuel delivery pipe and to reduce the weight of the engine.

(Means for Solving Problems and Actions) The above-described object of the present invention is to draw an end portion of a main pipe into a circular shape, fix a thin pipe by brazing, and fix the main pipe and the fuel pipe in an axial direction thereof. It is achieved by connecting directly to.

Based on such a configuration, according to the present invention, the end of the main pipe having a square cross section is squeezed into a circular shape by pressing or swaging, and the end of the thin fuel supply pipe is inserted into the end of the main pipe and copper brazing is performed. It is fixed by.

Therefore, there is no need to weld the adapter or bolt the eye joint as in the conventional case, the number of parts is reduced, the number of processing steps is reduced, and the cost is significantly reduced. Furthermore, the weight of the fuel delivery pipe is reduced, and the overall weight of the engine is reduced.

Other features and advantages of the present invention are shown in FIGS. 1 to 4 of the accompanying drawings.
It will be apparent from the following description with reference to the figures.

(Embodiment) FIGS. 1 to 4 show a connecting portion of a fuel delivery pipe 20 to a fuel supply pipe 2 according to a preferred embodiment of the present invention, and a portion not shown is a fifth portion. The structure is almost the same as the figure.

According to the present invention, the end portion 22 of the main pipe 1 having a rectangular cross section is pressed into a substantially circular cross section, the fuel supply pipe 2 is inserted therein, and the outer periphery 23 of the insertion portion is brazed with copper. There is. As described above, according to the present invention, the fuel supply pipe 2 is inserted into the end portion of the main pipe 1 having a rectangular cross section from the axial direction thereof, so that the fuel supply pipe 2 is inserted from the side portion of the main pipe 1. The performance as a fuel delivery pipe can be maintained without pressure drop.

The end portion 22 of the main pipe 1 can be processed by various methods such as a pressing method and a swaging method. If necessary, a circular core material can be inserted into the inside before processing.

FIG. 4 shows an embodiment in which the difference between the inner diameter of the main pipe 1 and the outer diameter of the pipe 2 is large. The end 22 of the main pipe 1 is drawn and the end 32 of the pipe 2 is enlarged. Then, the inner diameter and the outer diameter of both are matched, and after the pipe is inserted, the outer periphery 23 of the insertion portion is brazed with copper. According to this method, the present invention can be applied even when there is a difference in size between the two.

Although the present invention has been described with reference to a fuel delivery pipe for an in-line four-cylinder engine, it is understood that the present invention is similarly applicable to fuel delivery pipes for other types of engines. I want to.

(Effect of the Invention) As described in detail above, according to the present invention, the conventional adapter and eye joint are not required, the man-hour is reduced, and the manufacturing cost of the fuel delivery pipe is reduced. Further, the weight is reduced and the engine can be made lighter, and the practical value thereof is remarkable.

[Brief description of drawings]

FIG. 1 is a partial bottom view showing an end of a fuel delivery pipe according to the present invention on a fuel supply side, and FIG. 2 is a line II in FIG.
-II is a sectional view taken along line III-III in FIG. 1, FIG. 4 is a sectional view similar to FIG. 3 showing another embodiment, and FIG. 5 is a conventional series. FIG. 6 is a perspective view showing an entire fuel delivery pipe for a four-cylinder engine, FIG. 6 is a sectional view showing a conventional adapter, and FIG. 7 is a partial side view showing a connecting portion with a fuel supply pipe by a conventional eye joint. . 1 …… Main pipe, 2 …… Fuel supply pipe 3 …… Fuel return pipe, 4 …… Socket 5 …… Bracket, 6 …… Adapter 10,20 …… Fuel delivery pipe 12 …… Age joint 22 …… Drawing part 23 …… Brazed part 32 …… Enlarged part

Claims (1)

[Scope of utility model registration request] 1. A main pipe having a fuel supply passage therein and having a rectangular cross section, and a main pipe projecting so as to intersect the main pipe, one end communicating with the fuel supply passage and the other end tip of a fuel injection nozzle. In a fuel delivery pipe comprising a plurality of sockets for receiving the main pipe, the end of the main pipe is drawn into a circular shape, a thin pipe is fixed by brazing, and the main pipe and the fuel pipe are directly connected in the axial direction. A fuel delivery pipe that is characterized by that.