JPH0566263U - Fuel delivery pipe - Google Patents

Abstract

(57) [Abstract] [Purpose] In a fuel injection type automobile engine, a part of the fuel delivery pipe that supplies fuel to the injection nozzle is molded with resin to facilitate processing and deform while ensuring rigidity. To prevent oil leakage. A metal insert is provided so as to project on a metal main pipe having a linearly extending fuel passage therein. A cylindrical socket for mounting the fuel injection valve is molded on the insert at a predetermined interval and closely fixed on the surface of the main pipe. [Effect] Since the pitch between sockets and the mounting angle of sockets are determined at the time of molding, accurate positioning is possible. Since the insert suppresses thermal deformation of the resin,
Oil leakage is prevented.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention is a fuel delivery pipe for supplying fuel delivered from a fuel pressure 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 present invention relates to an improvement, particularly to a connection structure between a main pipe having a fuel passage and a socket for mounting a fuel injection valve.

[0002]

[Prior Art]

 The conventional fuel delivery pipe is installed with a fuel injection valve as shown in, for example, Japanese Utility Model Publication No. 57-84362 “Delivery Pipe for Fuel Injection Type Internal Combustion Engine” and Japanese Utility Model Publication No. 59-40577 “Delivery Pipe”. A plurality of cylindrical sockets for receiving the shaft are arranged at regular intervals on a main pipe having a circular or square cross section. The cylindrical socket is classified into a type welded to the main pipe and a type integrally formed with the main pipe.

Since the fuel injection valve must be installed in the intake hole of the intake manifold of the engine by aligning its axis accurately, the spacing between sockets and the installation angle must be within strict tolerances. I have to. For this reason, the type in which the socket is welded to the metal main pipe requires a lot of man-hours and time to perform complicated and precise processing for manufacturing the socket itself, and further, temporary work is required in connection work between the socket and the main pipe. Also, after the brazing process, a 100% inspection process by die matching is required in order to obtain high dimensional accuracy, leading to an increase in cost.

In the type in which the socket is made integrally with the main pipe, the entire fuel delivery pipe is made of aluminum die cast or aluminum extruded material as disclosed in, for example, Japanese Utility Model Publication No. 59-107050 “Delivery Pipe Device”. However, since the surface treatment is performed after the whole is molded, the surface treatment tends to be non-uniform, and since the draft for the molding die is required, the wall thickness increases and the weight increases. There were drawbacks such as it was difficult to find defects such as internal nests, quality assurance could not be obtained, and it was difficult to deal with design changes.

In Japanese Utility Model Laid-Open No. 60-14276 “Fuel distribution pipe for internal combustion engine”, the entire fuel delivery pipe is formed of a composite material in which a reinforcing fiber material is mixed with a synthetic resin, but the heat resistance is insufficient. In addition, there are drawbacks such as the whole being bent or distorted due to expansion and contraction due to heat, and the synthetic resin swells and deteriorates when the fuel passes through the inside.

[0006]

[Problems to be solved by the device]

 An object of the present invention is to mold a part of a fuel delivery pipe with a resin, thereby facilitating processing and ensuring rigidity to suppress deformation and prevent oil leakage. Another object of the present invention is to provide a fuel delivery pipe in which the positioning accuracy between the sockets is improved, and there is no damage or oil leakage from the connection portion with the fuel injection valve. Still another object of the present invention is to eliminate the drawbacks of the fuel delivery pipe including the resin portion, suppress the deformation due to heat, and enable a compact design.

[0007]

[Means for Solving the Problems]

 The above-mentioned object of the present invention is to provide a metal main pipe having a linearly extending fuel passage therein, and a protrusion projecting across the main pipe so that one end communicates with the fuel supply passage and the other end is outside the main pipe. This is accomplished by a fuel delivery pipe comprising a generally cylindrical metal insert extending in a straight line and a socket molded on the insert to receive the tip of a fuel injection nozzle.

According to this structure, a metal insert is projectingly provided on the main pipe of the fuel delivery pipe, and a resin socket is molded on the insert, which facilitates the processing of the fuel delivery pipe. .. The pitch between the sockets and the mounting angle of the sockets are determined at the time of molding, which enables accurate positioning. Since the socket is molded on the substantially cylindrical metal insert, the contact area between the two is large, high airtightness is maintained, and oil leakage can be prevented. Compared to the case of using only resin, the metal insert has an effect of suppressing thermal deformation, so that oil leakage due to thermal deformation can be prevented.

The resin socket is molded by molding so as to closely adhere to and cover the communication pipe. Resin sockets are molded at a relatively low temperature compared to the high temperature during welding, which prevents thermal deformation during manufacturing, maintains dimensional accuracy, and facilitates connection with the fuel injection nozzle. Is obtained.

It is desirable that the metal insert and the metal main pipe are tightly connected to each other through a protrusion or a bent portion or a concavo-convex portion provided with a pilot hole or the like, and fixed by brazing or the like. .. The metal insert itself has the advantage that it does not require strict accuracy in terms of diametrical dimensions and surface roughness, and does not require strict accuracy in terms of mutual pitch and mounting angle when it is fixed on the main pipe. Other features and advantages of the present invention will be apparent from the following description with reference to the embodiments of the accompanying drawings.

[0011]

【Example】

 FIG. 1 shows an entire fuel delivery pipe 10 according to a preferred embodiment of the present invention, in which a resin-made cylindrical socket 14 is installed at a predetermined interval on a main pipe 12 made of metal and having a box-shaped cross section. It is provided individually. Since the illustrated fuel delivery pipe 10 is used in an 8-cylinder V-type engine in combination with one pair, four socket portions 14 are provided, but when used in a V-type 6-cylinder engine, Three socket portions 14 will be provided.

A flange 16 for introducing high-pressure fuel sent from a fuel pump through a pressure regulating valve is connected to one end of the main pipe, and surplus fuel is introduced to the other end of another cylinder or a fuel tank. Connecting pipes 18 for delivery to the are connected to the straight main pipe 12 by welding or brazing, respectively. A thick and solid bracket 20 for attaching the fuel delivery pipe 10 to the engine is further fixed to the main pipe 12 by welding or brazing.

FIG. 2 is a sectional view showing the connection structure between the main pipe 12 and the socket 14, which is the subject of the present invention. A metal insert 30 is seated on the main pipe 12, and a resin socket 14 is molded on the insert 30. The insert 30 is composed of four parts: an annular part 31 protruding downward, a disc part 32 seated on the main pipe, a cylindrical part 33 extending in the vertical direction, and a flange part 34 extending horizontally from the upper end. There is. The annular portion 31 projecting downward is inserted into the pilot hole 24 formed at a predetermined interval on the main pipe 12, and the disc portion 32 is seated on the main pipe, and the periphery thereof is brazed. The main pipe 12 and the insert 30 are fixed via the uneven portion.

Subsequently, a predetermined surface treatment is performed with the main pipe 12 and the insert 30 fixed. Then, it is set in a molding machine and a synthetic resin is injected and solidified around the insert 30 to mold the socket 14. According to this method, it is possible to prevent surface stains and deterioration of corrosion resistance that occur when welding or brazing is performed after the surface treatment.

The resin socket 14 has a smooth inner peripheral surface, and the outer end side thereof is formed to be expanded in a tapered shape to facilitate connection with the fuel injection nozzle. The flange portion 34 at the upper end of the insert serves to fix the resin socket 14 so as not to drop out of the insert 30.

FIG. 3 shows a sectional view of another embodiment of the connection structure of the main pipe and the socket. A metal insert 50 is seated on the main pipe 12, and the socket 44 is molded on the insert 50. The insert 50 is provided with a ring-shaped bulging portion 54 instead of the flange portion 34 in the embodiment of FIG. 2, and fixes the resin socket 44 so as not to fall off from the insert 50.

The annular portion 51 projecting downward is inserted into the pilot hole 24 formed on the main pipe 12 at a predetermined interval, and by brazing the periphery, the main pipe 12 and the insert 50 form an uneven portion. Fixed through.

Many variations can be considered for the connection structure of the main pipe and the socket. The material of the main pipe is preferably steel or aluminum, and the resin is preferably heat-resistant plastic. In the illustrated embodiment, the socket is fixed at a right angle to the main pipe, but the present invention can also be applied to a fuel delivery pipe of a type in which the socket is fixed on the main pipe in a slightly inclined state. ..

[0019]

[Effect of the device]

 As described in detail above, according to the present invention, a part of the fuel delivery pipe is molded with resin, so that a part of the machining process can be omitted and the process becomes easy. Since the pitch between sockets and the mounting angle of sockets are determined at the time of molding, accurate positioning is possible. Since the socket is molded on a substantially cylindrical metal insert, the contact area between them is large, high airtightness is maintained, and oil leakage can be prevented. Further, as compared with the case of using only resin, the metal insert has an effect of suppressing thermal deformation, so that oil leakage due to thermal deformation can be prevented. Thus, a fuel delivery pipe having sufficient rigidity and dimensional accuracy can be obtained, and quality improvement and cost reduction can be achieved, and its practical value is remarkable.

[Brief description of drawings]

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

FIG. 2 is a cross-sectional view of a socket portion taken along a direction transverse to a main pipe.

FIG. 3 is a cross-sectional view of a socket portion taken along a direction transverse to a main pipe according to another embodiment.

[Explanation of symbols]

10 Fuel Delivery Pipe 12 Main Pipe 14 Resin Socket 24 Pilot Hole 30, 50 Insert 31 Projecting Annular Portion

Claims (2)

[Scope of utility model registration request] 1. A metal main pipe having a linearly extending fuel passage therein, and a projecting portion that intersects with the main pipe and has one end communicating with the fuel supply passage and the other end extending outside the main pipe. A fuel delivery pipe, comprising: a substantially cylindrical metal insert and a socket that is molded on the insert to receive a tip of a fuel injection nozzle. 2. The fuel delivery pipe according to claim 1, wherein the main pipe and the insert are fixed to each other via an uneven portion.