JPH0216059Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to an injection valve mounting structure for a fuel injection multi-cylinder engine.

[Prior art]

Recently, there has been a trend in vehicle engines to employ fuel injection valves as fuel supply devices in place of conventional carburetors, and various mounting structures for this fuel injection valve have been known. For example, in a fuel injection multi-cylinder engine, the tip of the fuel injector is inserted into the mounting hole provided in the branch of the intake manifold, and the upper end of the fuel injector is inserted into the fuel supply port of the delivery pipe. A delivery pipe is fastened and fixed to a stay provided in a branch part of the intake manifold using a mounting bolt, and a fuel injection valve is pressed and fixed to a branch part of an intake manifold using the delivery pipe.

In addition, in vehicle engines, from the perspective of increasing engine output, various efforts have been made to utilize intake inertia to improve charging efficiency.As a result, the branches of recent intake manifolds have become longer. There is a tendency to In this case, simply extending the branch part in the width direction of the engine would cause layout problems due to the space in the engine room, so the upstream side of the branch part is curved upward, that is, toward the fuel injection valve. I am trying to connect it to a surge tank.

However, in a fuel injector multi-cylinder engine having the above-mentioned injection valve mounting structure, if the upstream side of the branch part of the intake manifold is curved upward as described above, processing tools and assembly tools can be used to prevent damage to the curved part of the branch part or surge. It interferes with the tank,
There are problems in that it becomes difficult to process the delivery pipe mounting surface of the stay and the mounting bolt holes, and the work for assembling the delivery pipe becomes complicated.

Therefore, in conventional fuel-injected multi-cylinder engines,
When the upstream side of the branch part of the intake manifold is curved upward, the branch part of the intake manifold is divided, and the delivery pipe mounting surface of the stay and the mounting bolt hole are The intake manifold was assembled after machining the intake manifold and assembling the delivery pipe, but with this method, it was necessary to interpose a gasket (seal) on the split surface of the branch part of the intake manifold, and a large number of mounting bolts were required. As a result, the number of parts increases, leading to an increase in costs and the number of assembly steps.
[Purpose of the invention] In view of the above problems, this invention is an injection method for a fuel injection multi-cylinder engine in which the delivery pipe mounting surface of the stay and the mounting bolt holes can be easily machined without dividing the branch part of the intake manifold. The present invention aims to provide a valve mounting structure.

[Structure of the idea]

Therefore, in this invention, in a fuel-injected multi-cylinder engine, the stay is formed separately from the branch part, and a stay mounting pedestal is formed in the branch part of the intake manifold, and the stay is mounted on the mounting pedestal. A positioning member is interposed between the mounting pedestals, which makes it possible to easily machine the delivery pipe mounting surface of the stay and the mounting bolt holes, and also allows the delivery pipe to be fixed accurately and reliably. It is something.

〔Example〕

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

1 to 3 show an injection valve mounting structure for a fuel injection multi-cylinder engine according to an embodiment of the present invention. In the figure, 1 is an engine, and the engine 1
A flange 4 at the downstream end of the branch portion 3 of the intake manifold 2 is fixed to the side wall of the branch portion 3.
The upstream side of the surge tank 5 is curved upward and connected to the bottom wall of the surge tank 5 . Note that 13 is a throttle chamber.

In addition, each branch portion 3 of the intake manifold 2
A mounting hole 3a is formed near the downstream end of the
A tip nozzle portion 6a of a fuel injection valve 6 is inserted into the attachment hole 3a, and an upper end portion of the fuel injection valve 6 is inserted into a fuel supply port 8a of a delivery pipe 8. Further, a stay mounting pedestal 7 is formed integrally with the branch portion 3 between adjacent branch portions 3 of the intake manifold 2, and a stay 9 is tightened and fixed to the mounting pedestal 7 with a mounting bolt 10. A dowel pin 11, which is a positioning member, is interposed between the mounting base 7 and the stay 9. The stay 9 is formed with a delivery pipe mounting surface 9a and a mounting bolt hole 9b, and the center axis a of the bolt hole 9b is set in the same direction as the center axis b of the fuel injection valve 6.

Further, the mounting surface 9a of the stay 9 is stacked with the mounting portion 8b of the delivery pipe 8, and the bolt hole 9b of the stay 9 is screwed with a mounting bolt 12 inserted through the mounting hole of the mounting portion 8b. The pipe 8 is fastened and fixed to the stay 9, and the fuel injection valve 6 is pressed and fixed to the branch portion 3 of the intake manifold 2 by the delivery pipe 8.

Next, the effects will be explained.

In this structure, the stay 9 is formed separately from the branch part 3 of the intake manifold 2. Therefore, when machining the delivery pipe mounting surface 9a and the mounting bolt hole 9b of the stay 9, a machining tool is required as in the conventional method. is the curved part of the branch part 3 and the surge tank 4.
There is no interference with the material, and machining can be performed easily.

When the stay 9 is attached to the branch part 3, the stay 9 is placed on the mounting pedestal 7 of the branch part 3, and the mounting bolt 10 is inserted into the bolt hole 9c of the stay 9 and screwed into the mounting pedestal 7. That's fine. At this time, since the dowel pin 11 is interposed between the mounting base 7 and the stay 9, the stay 7 can be securely fixed at an accurate position.

When assembling the delivery pipe 8 and the fuel injection valve 6, insert the tip of the fuel injection valve 6 into the mounting hole 3a of the branch part 3 of the intake manifold 2, and insert the upper end into the fuel supply port of the delivery pipe 8. 8a, align the mounting portion 8b of the delivery pipe 8 with the mounting surface 9a of the stay 9, and insert the mounting bolt 12 into the mounting hole of the mounting portion 8b to secure the mounting bolt hole 9b of the stay 9. Just screw it together. At that time, the mounting bolt 12 can be tightened in the direction of the central axis b of the fuel injection valve 6 by inserting a tightening tool between the adjacent branch parts 3, and thereby the fuel injection valve 6 can be securely tightened. Can be fixed by pressing.

In the structure of this embodiment as described above, the stay is formed separately from the intake manifold, so the delivery pipe mounting surface of the stay and the mounting bolt hole can be easily formed without dividing the branch part of the intake manifold. It can be processed into

In addition, in this structure, the stay is provided between adjacent branch parts of the intake manifold, so
When assembling the delivery pipe, the tightening tool does not interfere with the curved portion of the branch portion or the surge tank, and as a result, the delivery pipe can be easily assembled.

In addition, with this structure, the stay is formed separately and attached to the intake manifold.
In this case, compared to the conventional case where the intake manifold is formed separately, a gasket is not required and the number of mounting bolts is also not required, so the number of parts can be reduced and costs can be reduced.

In the above embodiment, the stay mounting base is formed between adjacent branch parts, but it may be formed on the upper surface of a suitable branch part. Further, the positioning member may be other than a dowel pin. Furthermore, the side shape of the intake manifold may not be substantially L-shaped but may be substantially C-shaped.

Further, in the above embodiment, the case where the intake manifold is integrally formed has been described, but the present invention can of course be similarly applied to the case where the intake manifold is formed separately.

[Effect of idea]

As described above, according to the present invention, in a fuel-injected multi-cylinder engine, the stay is formed separately from the branch part, and the stay mounting pedestal is formed in the branch part of the intake manifold, and the stay is mounted on the mounting pedestal. At the same time, since a positioning member is interposed between the stay and the mounting base, the delivery pipe mounting surface and mounting bolt holes of the stay can be easily machined without having to separate the intake manifold, and the delivery pipe can be mounted accurately. Moreover, it has the effect of being able to be fixed securely.

[Brief explanation of the drawing]

Fig. 1 is a side view of an injector mounting structure for a fuel-injected multi-cylinder engine according to an embodiment of the present invention, Fig. 2 is a sectional view taken along the - line in Fig. 1, and Fig. 3 is an enlarged view of the main parts of the above structure. It is. 2...Intake manifold, 3...Branch section,
6...Fuel injection valve, 7...Stay mounting base, 8...
... Delivery pipe, 9 ... Stay, 11 ... Knock pin (positioning member), 12 ... Mounting bolt.

Claims (1)

[Scope of utility model registration request] In a fuel injection multi-cylinder engine in which fuel injection valves are provided in each of a plurality of branches of the intake manifold, a stay mounting pedestal is formed in the branch part of the intake manifold, the stay is attached to the mounting pedestal, and the stay is attached to the branch part of the intake manifold. A positioning member is provided between the fuel injection valve and the mounting base, a delivery pipe is tightened and fixed to the stay by a mounting bolt, and the fuel injection valve is pressed and fixed to the branch portion by the delivery pipe. Injector mounting structure for fuel-injected multi-cylinder engines.