JPH085337Y2 - Fuel injector mounting device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a mounting device for a fuel injection valve provided in an engine.

(Prior art and its problem) In the case of a multi-cylinder engine in which a plurality of injectors are attached to an intake pipe or the like, it may not be possible to individually fasten each fuel injection valve due to space limitations.

As a device for mounting such a fuel injection valve, as disclosed in, for example, Japanese Utility Model Laid-Open No. 63-69768,
In some cases, a tubular fuel tube that supplies fuel serves as a structural member that holds a plurality of fuel injection valves, and the front and rear ends of the fuel tube are fastened to the intake pipe at two locations.

However, in such a mounting structure, when an elastic material is interposed on the seat surface on which the fuel injection valve is seated to seal this portion, the reaction tube from the compressed elastic material causes the fuel tube to bend. As a result, in the fuel injection valve far from the fixing point of the fuel tube, the bending of the fuel tube becomes large, so that the fuel tube cannot give sufficient supporting force to the injector, and there is a concern that fuel leakage may occur.

The present invention aims to solve these conventional problems.

(Means for Solving Problems) In order to achieve the above object, the present invention provides a fuel tube for guiding fuel to a plurality of fuel injection valves, and a means for fixing the fuel tube to the engine block. An elastic material is interposed between the fuel injection valve side and the engine block, and the fuel tube has the function of supporting each fuel injection valve against the engine block while compressing the elastic material, and is joined to a common elastic material. The distance between the seat surface of each fuel injection valve and the seat surface of the engine block is reduced in proportion to the distance between the fuel tube fixing means and each seat surface.

(Operation) Based on the above configuration, in the state where there is no bending in the fuel tube, the distance between the seat surface of each fuel injection valve side and the seat surface of the engine block is formed to be small by the amount of the bending that occurs in the fuel tube. While compressing each elastic material while bending the elastic member, the compression amount of each elastic material can be made uniform and the surface pressure of the elastic material applied to each seat surface can be evenly and appropriately maintained. It is possible to prevent fuel leakage or the like from occurring.

(Embodiment) An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

In the figure, reference numeral 1 is an intake manifold provided between the left and right banks of a V-type 6-cylinder engine, and has intake passages 2 communicating with the # 1 to # 6 cylinders, respectively.

Reference numeral 4 in the figure denotes a fuel injection valve provided for each cylinder. Fuel injected from the fuel injection valve 4 is supplied to each cylinder via each intake passage 2, and the fuel injection amount and injection timing are not shown in the figure. The circuit adjusts according to the engine operating conditions.

In the figure, 11 to 16 are injector housings for accommodating the respective fuel injection valves 4, and 5 and 6 in the figure are two fuel tubes provided for each of the left and right banks. The left fuel tube 5 is integrally connected with the three injector housings 12, 14, 16 and the right fuel tube 6 is integrally connected with the three injector housings 11, 13, 15.

The front ends 5b and 6b of the left and right fuel tubes 5 and 6 communicate with each other through separate pipes, and the rear end 6a of the right fuel tube 6 communicates with a fuel pump (not shown) to allow pressurized fuel to flow in, while the left side It communicates with the fuel tank via a pressure regulator connected to the rear end 5a of the fuel tube 5, and after distributing a predetermined pressurized fuel to each injector housing 11-16, the surplus fuel is returned to the tank. There is.

Reference numeral 31 denotes the fuel injected from the fuel injection valve 4 in the intake passage 2
32 and 33 are seal rings for sealing between the fuel injection valve 4 and the injector housings 11 to 16, 34 is a cap provided on the upper part of each injector housing 11 to 16, and 35 is a cap. An insulator made of an elastic material is provided between the cap 34 and the fuel injection valve 4, and 36 is a screw for fastening the cap 34.

An annular insulator 7 made of an elastic material such as rubber is interposed between each injector housing 11 to 16 and the intake manifold 1.

A seat surface 19 that is joined to the insulator 7 is projectingly formed on each injector housing 11 to 16, while a seat surface 8 that is joined to the insulator 7 is formed on the intake manifold 1.
Are concavely formed.

As a fixing means for fixing the left and right fuel tubes 5, 6 to the engine block, brackets 21 to 24 are respectively coupled to the front and rear portions of the fuel tubes 5 and 6, and one end of each bracket 21 to 24 is taken in via a bolt 18. It is fastened and fixed to the manifold 1. Therefore, the left and right fuel tubes 5 and 6 are respectively supported by the intake manifold 1 at two positions in the front and rear portions.

The gist of the present invention is that the distance between the seat surface 19 of the injector housings 11 to 16 and the seat surface 8 of the intake manifold 1 that are joined to the common elastic member 7 in a state where the fuel tubes 5 and 6 are not bent. Is reduced in proportion to the distance of the insulator 7 to the brackets 21-24.
In this embodiment, the thickness T of each insulator 7 is formed to be constant, and each injector housing 11, 13, 15 or 1 is formed.
The seat surfaces 19 of 2, 14, 16 are formed on the same plane, and the reference surfaces 9 of the intake manifold 1 are formed in a plane shape parallel to the seat surfaces 19, while the seat surfaces 8 of the seat surfaces 8 are formed. The depth L with respect to the reference plane 9 is formed to be small in proportion to the distance from each bracket 21 to 24, and becomes shallower as it goes away from each bracket 21 to 24.

Specifically, as shown in the table of FIG. 3, the # 1 cylinder located in front of the engine and the # 1 cylinder located behind the engine.
The depth L of each seating surface 8 of the 6 cylinders is set to 7.3 mm for the respective distances from the right front bracket 23 or the left rear bracket 22 and is set to 7.3 mm, respectively. The depth L of each seat surface 8 of the # 5 cylinder located second from the rear is set to 7.1 mm, and the depth L of each seat surface 8 of the # 3 and 4 cylinders located in the center is 6.9 mm and 7.0. mm is set relatively small.

With this structure, the left and right fuel tubes 5,
6 is a double-supported beam structure that is supported at both ends via the brackets 21 to 24. With the insulators 7 compressed, the brackets 21 to 24 are fastened, and the reaction force from each insulator 7 causes each bracket to Deflection increases toward the central part away from 21 to 24.

Depending on this bending, the depth L of each seating surface 8 is set to each bracket 21.
Seat surface of each injector housing 11 to 16 that is formed to be smaller as it goes away from ~ 24 and is joined to the common insulator 7.
By forming the distance between 19 and the seating surface 8 of the intake manifold 1 to be small by the amount of bending that occurs in the left and right fuel tubes 5 and 6, each of the left and right fuel tubes 5 and 6 is fixed by compressing each insulator 7. The amount of compression of the insulator 7 is made uniform, and the surface pressures on the bearing surfaces 8 and 19 are made uniform and proper. As a result, even in the # 3 and 4 cylinders in which the left and right fuel tubes 5 and 6 are largely bent, the surface pressure of the insulator 7 is appropriately maintained, and fuel leakage occurs between the seat surfaces 8 and 19 and the insulators 7. It can be prevented.

As another embodiment, the seat surfaces 19 of the injector housings 11 to 16 and the intake manifold 1 which are joined to the common elastic member 7 in a state where the fuel tubes 5 and 6 are not bent.
The distance from the seat surface 8 of each injector 21 to 24 is reduced in proportion to the distance of each insulator 7 to each bracket 21. Therefore, the protrusion amount of the seat surface 19 of each injector housing 11 to 16 is changed, It is also conceivable to interpose different spacers.

The present invention can also be applied to an apparatus in which an elastic material is directly interposed between the fuel injection valve and the intake manifold, and an injector housing integrally formed with the fuel tube holds the upper portion of the fuel injection valve. .

As described above, according to the present invention, the fuel tube is provided with a function of supporting the plurality of fuel injection valves with respect to the engine block while compressing the elastic material, and each fuel joined to the common elastic material. Since the distance between the seat surface on the injection valve side and the seat surface on the engine block is reduced in proportion to the distance between the fixing means of the fuel tube and each seat surface, a multi-cylinder engine in which a plurality of fuel injection valves are provided side by side Also in this case, the compression amount of each elastic member can be maintained evenly and properly, fuel leakage or the like can be prevented from occurring through the elastic member, and vibration of the fuel injection valve or the like can be effectively suppressed.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of the present invention, FIG. 2 is an exploded view, and FIG. 3 is a table showing the depth of each seat surface. 1 ... Intake manifold, 4 ... Fuel injection valve, 5, 6 ...
Fuel tube, 7 ... Insulator, 8 ... Seating surface,
11-16 ... Injector housing, 19 ... Seating surface, 21-24 ...
bracket.

Claims (1)

[Scope of utility model registration request] 1. A fuel tube for guiding fuel to a plurality of fuel injection valves is provided, means for fixing the fuel tubes to the engine block is provided, and an elastic material is interposed between each fuel injection valve side and the engine block. The fuel tube has a function of supporting each fuel injection valve against the engine block while compressing the elastic material, and the seat surface of each fuel injection valve and the seat surface of the engine block that are joined to the common elastic material are joined together. The fuel injection valve mounting device is characterized in that the distance between the fuel tube and the seating surface is reduced in proportion to the distance between the fuel tube fixing means and each seat surface.