JP2981924B2 - Fuel delivery pipe - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to supplying fuel supplied from a fuel pressurizing pump of a fuel injection type automobile engine to each intake passage or each cylinder of the engine through a fuel injector (injection nozzle). The improvement of fuel delivery pipes.

[0002]

2. Description of the Related Art A typical structure of a fuel delivery pipe for injecting fuel toward one or three cylinders or four cylinders on one side of a fuel injection type V-type six or eight cylinder engine is as follows.
For example, it is described in Japanese Utility Model Laid-Open Publication No. 62-152073, "Fixed support device for fuel injection valve". Same type of full Ewell delivery pipe "fuel supply device for an internal combustion engine" No. Sho 63-158583, are also described in such as "fuel injection system for an internal combustion engine" real-Open 2-14464 Patent. A fuel delivery pipe of this type has a communication pipe connected to a central portion of a body of a socket, and is called a bottom flow type. The socket of a bottom flow type fuel delivery pipe is generally made of a forged product or a cast product, and its cross-sectional shape is formed into a considerably complicated shape.

[0003] The fuel delivery pipe is provided with sockets (housings) corresponding to the number of the injectors on the engine side, but the mounting position of each socket must match the position of the injector on the engine side. The central axis of the shaped socket must exactly match the axis of the injector. Therefore, in manufacturing the fuel delivery pipe, the positioning of the socket is important, and strict dimensional accuracy is required for the mounting pitch and the mounting angle between the sockets. If the correct dimensional accuracy cannot be obtained, it may be difficult to attach the fuel delivery pipe to the injector, or the fuel may leak after the attachment.

However, the above-mentioned Japanese Patent Application Laid-Open No. 62-15 / 1987
In a conventional general fuel delivery pipe such as No. 2073, a communication pipe is welded between sockets, and this welding is a welding in which a so-called saddle-shaped cross section is joined, so that thermal expansion and Distortions such as heat shrinkage occur, and the position and angle of the socket are deviated, so that a predetermined dimensional accuracy cannot be obtained.

[0005] As another manufacturing method, a fuel delivery pipe manufactured by using aluminum die casting is subjected to a surface treatment after forming the whole, so that the surface treatment is likely to be non-uniform, and a molding die is required. Due to the necessity of draft, the wall thickness increases and the weight increases, it is difficult to find defects such as internal nests, and quality cannot be guaranteed, and it is difficult to deal with design changes. There were drawbacks.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to improve the dimensional accuracy of the positioning of the socket portion and the overall rigidity to improve the quality of the fuel delivery pipe. Another object of the present invention is to reduce the cost by simplifying the manufacturing process of the fuel delivery pipe. Still another object of the present invention is to increase the surface area of the fuel delivery pipe to enhance heat dissipation, and to prevent the generation of vapor inside the fuel delivery pipe.

[0007]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a fuel delivery system for an internal combustion engine comprising a plurality of hollow cylindrical sockets for receiving fuel injection valves and a communication pipe connecting the sockets. in the pipe, up to greater than the outer diameter of the body portion of the communicating pipe is the socket
It is made of a pipe material having a diameter (maximum width except for a circular cross section) portion, and a hole for receiving an outer peripheral portion of each socket is provided on an opposing surface of the pipe material so as to penetrate each opposing surface. This is achieved by a fuel delivery pipe that is integrally formed by brazing or welding around the socket with the socket seated in the hole.

In the fuel delivery pipe according to the present invention, since the communication pipe is integrally formed of a wide pipe material, the fuel delivery pipe has high rigidity and can prevent thermal distortion when the socket is welded. Since the communication pipe has a maximum diameter (maximum width except for the circular cross section) larger than the outer diameter of the socket, holes for accommodating the body of the socket must be accurately machined at a predetermined pitch. Can be.
Since the periphery of the socket is brazed or welded while seated in the hole, the mounting pitch and the mounting angle between the sockets are accurately maintained at predetermined values.

In the fuel delivery pipe according to the present invention, since the communication pipe is formed integrally with the pipe material, the process of welding a plurality of communication pipes to the middle of the socket as in the prior art is simplified. Man-hours are reduced, and costs are reduced. Further, since the communication pipe is made of a wide pipe material, the surface area is increased, the heat radiation is improved, and the generation of vapor inside is effectively suppressed.

[0010] The cross section of the communicating pipe made of a pipe material can be mainly a wide rectangle, ellipse, or circle, and a cap member is welded to one or both ends of the pipe material to form a whole sealed structure. Is preferred.

The socket can be formed by machining a forged or cast product as in the prior art, or by pressing a steel plate. Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings.

[0012]

FIG. 1 shows an entire fuel delivery pipe 10 according to the present invention. The fuel delivery pipe 10 is used for supplying fuel to four cylinders on one side of a V-type eight-cylinder engine. Will be The fuel delivery pipe 10 is fixed to four hollow sockets 21A, 21B, 21C, 21D arranged at predetermined intervals, a communication pipe 22 having a wide and rigid rectangular section, and both ends of the communication pipe 22. It is composed of cap members 23 and 24 and an inlet pipe 25 and an outlet pipe 26 attached to the fuel inlet and outlet on the side of the communication pipe 22.

FIG. 2 shows a cross section of the socket portion cut in a direction transverse to the communication pipe 22, and through holes 31 and 32 are vertically formed so as to be orthogonal to the maximum width portion of the communication pipe 22 having a rectangular cross section. The body portion 41 of the socket 21A is accommodated therein, and the periphery thereof is brazed or welded. The diameter of the through hole 32 can be made equal to or smaller than the diameter of the through hole 31.

The internal structure of the socket 21A is the same as that of the conventional one, and has smooth inner peripheral surfaces 42 and 43 for receiving the fuel injector introduction shaft, a tapered expanding portion 44 at the upper end, and a lower end. Opening 45 reduced in diameter on the side
Are formed. A through hole 48 is provided at the center of the body of the socket 21A for sending out the fuel that has flowed into the communication pipe to the injector side.

FIG. 3 shows a cross section of the socket section cut along the longitudinal direction of the communication pipe 22, showing a state in which a cap member 23 is fixed to an end of the communication pipe 22 by welding. A flange portion 51 having a bolt hole 50 is integrally formed on the left and right ends of the upper end of the socket 21A, and a cap for fixing the fuel injector is bolted using this. Therefore, similarly to the conventional socket, the fuel injector is smoothly received and sealed by the O-ring. In FIG. 3, only one pair of the through holes 48 is provided. However, when it is desired to increase the fuel flow rate or to improve the cooling performance of the injector, three or more holes are provided around the socket body. Can be formed.

FIG. 4 shows an embodiment in which the cross section of the communication pipe is made elliptical. Since the communication pipe 62 has high rigidity against torsion based on its elliptical cross section, it has an advantage of being excellent in durability against engine vibration.

FIG. 5 shows the communication pipe 22 for providing the bolt hole 50 shown in FIG. 3 without forming the flange portion 51.
An embodiment in which a tapped block 71 is welded on the upper side is shown. The threaded portion 70 of the tapped block 71 performs the same function as the bolt hole 50 of FIG. According to this embodiment, the socket 21A does not require the flange portion 51 as shown in FIG. 3, and the mold for forging or casting is simplified,
This has the advantage that the number of machining steps is significantly reduced. A weld nut can be used instead of the tapped block 71.

FIG. 6 shows an embodiment in which the socket 81 is formed from a steel plate by press working and brazed to the communication pipe 22. A block 83 with a tap is welded to the lower surface of the left-right protruding portion 82 at the upper end to perform the same operation as the bolt hole 50 in FIG. According to this embodiment, since the socket is completed in a short time by press working, the working process of the fuel delivery pipe is remarkably shortened, and the cost is reduced.

FIG. 7 shows a modification of the embodiment shown in FIG. 6, in which the size of upper and lower through holes 92 and 93 for receiving a socket formed in the communication tube 90 is changed. The lower through hole 93 functions to seat a stepped portion outside the socket 91, and the upper through hole 92 positions the socket 91 in the same manner as in the above-described example. According to this example, since the positioning of the socket in the vertical direction is achieved in a state where the socket 91 is seated in the communication pipe 90, there is an advantage that welding and brazing operations are facilitated.

[0020]

As described above in detail, according to the fuel delivery pipe of the present invention, the dimensional accuracy of the positioning of the socket portion is enhanced, so that the assembling work to the engine becomes easy. In addition, the communication pipe has a structure that is resistant to torsion, thereby increasing the overall rigidity, preventing fuel leakage, and improving the quality of the fuel delivery pipe. In addition, the heat dissipation is enhanced by increasing the surface area, the generation of vapor inside the fuel delivery pipe is reduced, and the reliability of fuel injection is enhanced. Furthermore, the manufacturing process of the fuel delivery pipe can be simplified and the cost can be reduced.
Its technical value is very significant.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an entire fuel delivery pipe according to the present invention.

FIG. 2 is a vertical cross-sectional view of a fuel delivery pipe according to the present invention in which a socket portion is cut in a direction crossing a communication pipe.

FIG. 3 is a longitudinal sectional view of a fuel delivery pipe according to the present invention, in which a socket portion is cut along a longitudinal direction of a communication pipe.

FIG. 4 is a longitudinal sectional view of a socket portion of the embodiment in which the cross section of the communication tube is made elliptical.

FIG. 5 is a longitudinal sectional view of the socket portion of the embodiment in which the flange portion of the socket is omitted.

FIG. 6 is a longitudinal sectional view of a socket portion of the embodiment in which the socket is formed by pressing.

FIG. 7 is a longitudinal sectional view of a socket portion showing a modification of the embodiment of FIG. 6;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Fuel delivery pipe 21A, 21B, 21C, 21D Socket 22 Communication pipe 23, 24 Cap 31, 32 Through hole 41 Body part 48 Through hole

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) F02M 55/02 330 F02M 55/02 340 F02M 55/02 350

Claims (4)

(57) [Claims] 1. A fuel delivery pipe for an internal combustion engine, comprising: a plurality of hollow cylindrical sockets for receiving a fuel injection valve; and a communication pipe connecting between the sockets, wherein the communication pipe is a body part of the socket. It is made of a pipe material having a maximum diameter or a maximum width portion larger than the outer diameter of the pipe material, and a hole for receiving an outer peripheral portion of each socket is provided on an opposing surface of the pipe material so as to penetrate each opposing surface. A fuel delivery pipe, wherein the whole is integrally formed by brazing or welding the periphery of the socket while the socket is seated in the hole. 2. The fuel delivery pipe according to claim 1, wherein a cross section of the communication pipe is rectangular. 3. The fuel delivery pipe according to claim 1, wherein a cross section of the communication pipe is elliptical. 4. The fuel delivery pipe according to claim 1, wherein each socket is formed by press-forming a steel plate.