JPH04334755A - Inlet manifold fuel supply assembly - Google Patents

Abstract

PURPOSE: To reduce number of components of a fuel supply assembly, by supplying fuel through a common fuel passage to a fuel injector held by two castings forming an inlet manifold. CONSTITUTION: An inlet manifold 13 is formed from two integrally bolted castings 14, 15. A closure formation 20 of the casting 15 retains a fuel injector 21 in a seat formation 19 of the casting 14. A common fuel passage 25 being provided in the inlet manifold 13 communicates with each of the seat formations 19 for supplying fuel to the fuel injector 21. Thus, since individual fuel rail is not required, number of components of a fuel supply assembly can be reduced.

Description

[Detailed description of the invention]

0001

TECHNICAL FIELD This invention relates to a combined inlet manifold fuel supply assembly for a fuel injected internal combustion engine incorporating a single row of cylinders having a common manifold.

0002

BACKGROUND OF THE INVENTION A typical inlet manifold fuel supply assembly for an internal combustion engine has a separate air inlet leading to each cylinder and is arranged to inject a metered amount of fuel into the inlet when required. a separate fuel injector for each air inlet. One known method of installing a fuel injector is to install the injector in a fuel rail and then install the fuel rail and injector as a single unit in a manifold.

The fuel rail typically has an inlet leading from the fuel tank via a pump, a return feeding the fuel tank via a pressure regulator, and individual fittings to the injectors in the manifold. ing.

0004

SUMMARY OF THE INVENTION It is an object of the present invention to provide a simplified inlet manifold fuel supply assembly.

In accordance with the present invention, there is provided an inlet manifold fuel supply assembly for a fuel-injected internal combustion engine incorporating a plurality of cylinders in a single row having a common inlet manifold for the rows of cylinders; , 2 connected along longitudinally extending interfaces of the rows of cylinders
formed of two parts, one part of the manifold comprising:
defining a plurality of seat structures, each seat structure configured to house a fuel injector, the seat structure opening at one end to an associated inlet passageway, and a closure structure corresponding to each seat structure;
A seat structure is provided in the other portion of the manifold to retain the fuel injectors within a common fuel passage within the manifold, the common fuel passage being provided at each seat for supplying fuel to the fuel injectors. It is characterized by communicating with the structure.

[0006] In this way, a separate fuel rail is no longer necessary, thus reducing the number of assembly components and the number of separate fuel couplings. Generally, reducing the number of components allows reducing costs and improving reliability.

Preferably, electrical connector rails are provided within the manifold to automatically make the necessary electrical connections to the injectors during assembly of the manifold. This eliminates the requirement for separate external wiring to the fuel rail and/or manifold.

[0008] Also preferably, the pressure relief valve is provided within a chamber defined by two portions of the manifold.

An embodiment of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

0010

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a highly schematic representation of the arrangement of a spark-ignited four-cylinder reciprocating internal combustion engine with a row of four cylinders. Apart from the fuel supply system, the engine itself is represented by a cylinder block, head 11, with four cylinders 12 in a common row. Inlet manifold 13 is arranged to provide an air-fuel mixture to the cylinder for combustion.

FIG. 2 shows that the manifold 13 is divided into two parts 14, 15 along an interface 16. Typically, both parts 14, 15 are aluminum castings with interfacial machined surfaces and other machined areas as required. The manifold includes four separate inlet passages 17, one to each cylinder. Alternatively, resin moldings may be used for the manifold. These passage-defining materials may be joined by webs 18 to form part of a common casting. Four seat structures 19, one for each inlet passageway 17, are provided in the lower portion 1 of the manifold 13 to accommodate the fuel injectors 21.
4. The seat structure 19 has an associated inlet passage 17
It opens at one end. Injector 21 is placed in position within seat structure 19 by a flange 22 that engages a spigot 23 formed at the end of seat structure 19 adjacent interface 16 . Portion 15 of manifold 13 defines four closure structures 20, each closure structure 20 corresponding to one seat structure 19, so that when the two sections 14, 15 of manifold 13 are bolted together, the closure Structure 20 clamps flange 22 within spigot 23 to retain injector 21 within seat structure 19. This results in
Injector 21 is completely enclosed within manifold 13.

The injectors are electrically controlled by signals supplied to each injector separately by an electrical connector rail 24 fixed in a longitudinal groove of the casting 15 opening to each closure structure 20. . The connector rail 24 is arranged so as to automatically make the required connection to the injector during assembly of the two parts 14, 15 of the manifold 13. Electrical connector rail 24 terminates in a multi-pin connector 30 that provides electrical signals to operate injector 21.

The longitudinal fuel passages 25 communicate with all four seat structures 19 in the casting 14, thus providing an equal common fuel supply to the fuel rails for all four injectors. Fuel is pumped (not shown) to inlet 29.
The fuel is supplied from the fuel tank to the passage 25 via the fuel tank. As shown in FIG.
3, the chamber is formed by parts 14, 15 of 3;
Install the pressure relief valve 27. A return pipe 28 leads from the downstream region of the chamber 26 to the fuel tank. The fuel is supplied to the two seals 33 of each injector 21 and the pressure relief valve 27.
is retained within the rail by a similar seal. Another seal 34 seals the interface 16.

Connector rail assembly 24 is first inserted into casting 15 along with multi-pin connector 30 to assemble a complete inlet manifold fuel supply assembly with individual finished components. Next, the individual injectors 2
1 are inserted into the seat structure 19 and placed in position within the spigot 23 by their flanges 22. A pressure relief valve 27 is similarly installed within the chamber 26. The upper casting 15 is then brought into engagement with the lower casting 14 and the electrical connection to the injector 21 is then made.
done automatically. The two castings 14, 15 are positioned together by devices such as locating pins or spigots and held together by a series of studs or bolts. Gaskets or sealing compounds are optionally used during assembly operations. Any required fittings of the fuel supply and return lines are then fitted.

Next, the completed manifold assembly is
The engine 11 is mounted in a conventional manner such that the passageway 17 is aligned with an inlet port 31 that connects to the cylinder 12 via an inlet valve 32. During use of the engine, the inlet manifold 13 and its fuel supply function in a normal manner.

The entire inlet manifold 13 fuel supply assembly is a unit consisting of a relatively small number of components leading to a simple assembly operation and providing the potential for very high reliability.

Although the invention is particularly applicable to spark ignition reciprocating engines, it may also be used in other types of engines, such as multi-cylinder rotary engines. Similarly, V6-cylinder or V8-cylinder or V12-cylinder engines may have the concept applied to the present invention.

[Brief explanation of the drawing]

FIG. 1 is a schematic plan view of a part of an engine incorporating part of a manifold, with the relative positions of the several parts modified for clarity;

FIG. 2 is an enlarged cross-sectional view of one cylinder and associated injector showing additional components.

[Explanation of symbols]

12 Cylinder 13 Inlet manifold 14 Lower part (casting) 15 Upper part (casting) 16 Interface 17 Entrance passage 19 Seat structure 20 Closed structure 21 Fuel injector 24 Electrical connector rail 25 Fuel passage 26 Chamber 27 Pressure relief valve

Claims (4)

[Claims] 1. An inlet manifold (13) fuel supply assembly for a fuel-injected internal combustion engine incorporating a plurality of cylinders (12) in a single row having a common inlet manifold (13) for the rows of cylinders (12); The manifold (13) has two parts (14) joined along a longitudinally extending interface (16) of said row of cylinders (12).
, 15), a portion (14) of the manifold (13) defining a plurality of seat structures (19), each seat structure (19) housing a fuel injector (21). The seat structure (19) is configured in such a way that the seat structure (19)
A closed structure (20) opening at one end to 7) and corresponding to each seat structure (19) is connected to the seat structure (19);
The common fuel passage (25) in the manifold (13) is provided in another part (15) of the manifold (13) so as to hold the fuel injector (21) in the common fuel passage (25). 25) communicates with said seat structure (19) for supplying fuel to said fuel injector (21). 2. An assembly according to claim 1, wherein the electrical connector rail (24) is connected to the manifold (1).
3), characterized in that it is arranged in said manifold (13) so as to automatically make the necessary electrical connections to said injector (21) during assembly. 3. An assembly according to claim 1 or claim 2, wherein the pressure relief valve (27) is arranged in a chamber (26) defined by two parts (14, 15) of the manifold (13). An assembly characterized in that it is provided in. 4. An assembly according to any one of claims 1 to 3, wherein the fuel passageway (25) extends along a first part (14) of the manifold (13), An assembly characterized in that the seat structure (19) is cut directly.