FR2738035A1 - IC engine intake manifold with grouped auxiliary vacuum connections - Google Patents

Abstract

Air-filter (1) and manifold (2) are both generally cylindrical plastic mouldings mounted on adjacent parallel axes beside the cylinder head. The filter's removable cap (10) forms a resonating cavity, reducing inrush noise; its main body (11), containing the element, has inlet (13) and outlet (12) orifices, and supports a rectangular socket (6) into which the engine management manifold pressure sensor (3) clips. The sensor connecting pipe (4) has e.g. 5 bends (14) to attenuate pressure fluctuations despite its relatively short length, and terminates (5), with other auxiliary connections, in alignment along a rectangular plate covering an elongated opening in the manifold top. Two connections, for crankcase and fuel fume extraction, are segregated from the rest to avoid cross-contamination.

Description

INTAKE MANIFOLD FOR A MOTOR
INTERNAL COMBUSTION
The present invention relates to an intake manifold for multi-cylinder internal combustion engines intended in particular for equipping motor vehicles, and more particularly to an intake manifold adapted to receive a plurality of nozzles used in particular for connecting the sockets depression.

 The function of the intake manifold, also called a distributor of a multi-cylinder internal combustion engine, is to communicate the outlet of the throttle body where the outlet of the air filter, and the inlet of the various intake ducts formed in the cylinder head of the motor. An intake manifold conventionally has a molded body which is fixed on the cylinder head of the engine; this body generally comprises a large-capacity distribution chamber also called a plenum and several pipes which leave from this distribution chamber to supply combustion air to each of the combustion chambers of the engine.

The intake manifold of an internal combustion engine is generally connected to a greater or lesser number of vacuum sockets used to operate components as diverse as the braking system or Master
Vac, the EGR valve, the fuel return valve fitted to the injection rail, etc., as well as to systems for adding non-combustible substances or secondary combustible substances to the combustion air, such as crankcase gases, fuel vapors from the canister or recirculated burnt gases.

 The tappings required for all these connections are, however, according to the known prior art, positioned on the intake manifold in a somewhat anarchic manner, which complicates the production of the manifold and the process of mounting the latter on the engine.

 The present invention therefore aims to remedy these drawbacks with an intake manifold for internal combustion engine of the aforementioned type which combines in a simple and economical manner almost all of the tappings necessary for the operation of the engine.

 The intake manifold according to the invention for a multicylinder internal combustion engine comprises a body having a distribution chamber cooperating with nozzles and nozzles intended to put the distribution chamber and the corresponding intake conduits formed in the cylinder head into communication of the motor.

 According to the invention, the intake manifold for an internal combustion engine is characterized in that the nozzles are carried by a single attached piece which is fixed to the body of the manifold in line with at least one corresponding opening opening into the distribution.

 According to another characteristic of the intake manifold for an internal combustion engine which is the subject of the invention, the nozzles assembled on the nozzle holder part are intended for the connection of pipes intended to add combustible or non-combustible substances to the combustion air. such as fuel vapors or crankcase gases, and / or the connection of vacuum sockets.

 According to another characteristic of the intake manifold for an internal combustion engine which is the subject of the invention, the nozzles are integral with the nozzle holder part.

 According to another characteristic of the intake manifold for an internal combustion engine object of the invention, the nozzles are grouped on the nozzle holder part according to their function and to each group of nozzles corresponds a suitable opening made through the body of the manifold to open into the distribution chamber.

 According to another characteristic of the intake manifold for an internal combustion engine which is the subject of the invention, the nozzle-carrying part is formed by a plate of generally rectangular shape, the nozzles being arranged aligned along the median longitudinal axis of the plate.

 According to another characteristic of the intake manifold for an internal combustion engine which is the subject of the invention, each of the openings made through the body of the manifold to cooperate with the nozzle-carrying part, comprises an oblong orifice surrounded by a wall extending in protrusion outside the body of the manifold, the free edge forming the joint plane of this wall having a groove serving as a housing for a corresponding boss carried by the nozzle-carrying part.

 According to a first embodiment of the intake manifold for an internal combustion engine which is the subject of the invention, the nozzles directly incorporate suitable connection ends.

 According to an alternative embodiment of the intake manifold for an internal combustion engine which is the subject of the invention, all or part of the nozzles carry, mounted by clipping, attached connection ends.

 According to another characteristic of the intake manifold for an internal combustion engine which is the subject of the invention, the body of the manifold and the nozzle-holder part are made of molded plastic.

The objects, aspects and advantages of the present invention will be better understood from the description given below of various embodiments of the invention, presented by way of non-limiting examples, with reference to the accompanying drawings, in which
Figure 1 is a partial perspective view of the intake manifold for an internal combustion engine according to the invention
Figure 2 is a detail view of the nozzle holder plate shown in Figure 1
Figure 3 is a partial sectional view in cross section of the intake manifold in line with one of the taps
Figure 4 is a view similar to that of Figure 3, showing an alternative embodiment of the taps.

 To make the drawings easier to read, the same parts have the same references from one figure to another. Furthermore, only the elements necessary for understanding the invention have been shown.

 Referring to Figure 1, we see an intake manifold referenced 1 for an internal combustion engine of the four-cylinder in-line type (with spark ignition or with compression ignition) equipping for example a motor vehicle.

 This manifold 1 made of plastic conventionally comprises a body molded having a distribution chamber or plenum 2 of substantially cylindrical shape, intended to extend parallel to the cylinder head, not shown, of the engine, and four pipes 3 directed substantially perpendicularly to the distribution chamber 2 and putting the latter in communication with the corresponding intake ducts formed in the cylinder head to supply combustion air or fuel mixture to each of the engine combustion chambers.

 The taps 6,7 which are respectively used for the connection of the recycling pipes in the air combustion of the crankcase gases and the fuel vapors from the canister as well as for the various vacuum connections, are according to the invention grouped on a single insert 4 extending parallel to the longitudinal axis of the distribution chamber 2.

 This generally rectangular plate 4, obtained in plastic material by molding, is fixed, by gluing or by welding (ultrasonic) in a sealed manner on the body 10 of the intake manifold 1 in line with two corresponding openings 26 , 27 opening into the distribution chamber 2 substantially upstream in the direction of the flow of air from the pipes 3 in particular for that 26 corresponding to the nozzles 6 intended for the addition of substances suitable for combustion air (substances non-combustible in the case of crankcase gases or combustible substances in the case of fuel vapors from the fuel tank and trapped by the canister), so as to obtain a homogeneous distribution of these in the different combustion chambers of the engine .

 In accordance with FIGS. 1 and 2, it can be seen that the nozzles carried by the plate 4 are aligned along the median longitudinal axis of the latter and grouped into two distinct groups 6 and 7 arranged at the two axial ends of the plate 4. In the part end 46 of the plate 4 are arranged the nozzles 6 corresponding to the introduction of non-combustible substances or secondary fuel while in the other end part 47 separated from the part 46 by an intermediate part of predetermined length 45 , are arranged the nozzles 7 corresponding to the different vacuum sockets of the engine.

 This arrangement of the tappings in two separate groups has the function of sufficiently distancing the tappings 6 used for adding substances to the combustion air from the tappings 7 used for the depressions, so as to prevent any rise of these substances through depression.

 Each group of taps 6 and 7 respectively corresponds to a single opening respectively 26, 27 opening into the distribution chamber 2. In accordance with FIG. 3, the opening 26 associated with the taps 6 is shown (the opening 27 associated with the nozzles 7 which extends in the extension of the opening 26 is perfectly similar to the latter except for the axial dimensions). This opening 26 is in the form of an oblong orifice 23 formed through the wall of the body of the intake manifold defining the distribution chamber 2.

 The oblong orifice 23 is surrounded by a wall 16 coming from molding with the body of the collector and extending projecting above the latter. The upper edge of this wall 16 forming a joint plane, has a peripheral groove 29 capable of receiving a complementary shouldered boss 64 extending under the part 46 of the plate around the different nozzles. Such an assembly allows both simple positioning of the two parts relative to each other and a tight fixing of the two parts, in particular by ultrasonic welding without unsightly burr formation.

 In accordance with FIG. 3, the tapping 6 integrates an individual chamber 61 of substantially cylindrical shape having a flared entry opening extending in the extension of the orifice 23, this chamber 61 opens out by a suitable connection endpiece 60 of the olive type (or fir type) extending perpendicular to the axis of the chamber 61. According to this exemplary embodiment the connection end piece 60 to which the corresponding connection pipe, not shown, is connected, is integral with the stitching 6.

 According to the variant embodiment shown in FIG. 4, the connection end piece 8 is not directly integrated into the corresponding tap 406 but clipped onto the latter. According to this embodiment, the end piece 8 comprises a connection end proper 80 forming a body with a cap 84 which is fixed removably on the nozzle 406 constituted by a suitable tube 406 coming from molding with the wafer.

 Of course, the invention is in no way limited to the embodiment described and illustrated, which has been given only by way of example.

 On the contrary, the invention includes all the technical equivalents of the means described and their combinations if these are carried out according to the spirit.

 Thus, the invention is not limited to only plastic intake manifolds but also applies to manifolds from the foundry.

 Furthermore, the invention is not limited, in particular as regards the plate 4 nozzle holders, to the single rectangular shape and to the location on the distribution chamber 2 which have been illustrated in the figures.

Claims (1)

 Lîl Intake manifold (1) for a multi-cylinder internal combustion engine comprising a body (10) having a distribution chamber (2) cooperating with a plurality of tappings (6,7; 406) and pipes (3) intended to put in communication, said distribution chamber (2) and the corresponding intake ducts formed in the cylinder head of the engine, characterized in that said tappings (6,7; 406) are carried by a single attached piece (4) coming to be fixed on said body (10) in line with at least one corresponding opening (26,27) opening into said distribution chamber (2).  [2] Intake manifold (1) for a multi-cylinder internal combustion engine according to claim 1, characterized in that said nozzles (6,7; 406) are intended for the connection of pipes intended to add to the combustion air combustible or non-combustible substances such as fuel vapors or crankcase gases, and / or the connection of vacuum sockets.  (3] Intake manifold (1) for a multi-cylinder internal combustion engine according to any one of claims 1 to 2, characterized in that said nozzles (6,7; 406) are integral with said part (4). [4] Intake manifold (1) for a multi-cylinder internal combustion engine according to any one of claims 1 to 3, characterized in that the nozzles (6,7; 406) are grouped on the part (4) according to their function and in that to each group of tappings (6,7; 406) corresponds an adapted opening (26,27) formed through the body (10) to open into said distribution chamber (2). [5] Intake manifold (1) for a multi-cylinder internal combustion engine according to any one of claims 1 to 4, characterized in that said part is formed by a plate (4) of generally rectangular shape and in that the nozzles (6,7; 406) are aligned along the median longitudinal axis of said plate (4). [6] Intake manifold (1) for a multi-cylinder internal combustion engine according to any one of claims 1 to 5, characterized in that each of said openings (26,27) comprises an oblong orifice (23) surrounded by a wall (16) projecting outside of said body (10) and in that the free edge forming a joint plane of said wall (16) has a groove (29) serving as a housing for a boss (64) corresponding carried by said part (4).  (7] Intake manifold (1) for a multi-cylinder internal combustion engine according to any one of claims 1 to 6, characterized in that said nozzles (6,7) incorporate suitable connection ends (60).  (8] Intake manifold (1) for a multi-cylinder internal combustion engine according to any one of claims 1 to 6, characterized in that all or part of said tappings (406) carry suitable connection ends (8), said end caps (8) clipping onto said nozzles (406).  (9] Intake manifold (1) for a multi-cylinder internal combustion engine according to any one of claims 1 to 8, characterized in that said body (10) and said part (4) are made of molded plastic. [10] Intake manifold (1) for a multi-cylinder internal combustion engine according to claim 9, characterized in that said part is fixed to said body (10) by ultrasonic welding.