JP2009228654A - Intake device of multicylinder engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the number of parts, cost, space and engine size as compared with a case where an intake manifold is separately provided outside a head cover.
SOLUTION: An intake manifold 12 for supplying intake air to a V-type multi-cylinder engine E is integrally formed inside a head cover 13 that covers the upper surface of a cylinder head 11. Therefore, the intake manifold 12 is separately provided outside the head cover 13. Compared to the case, the number of parts, the cost, the space, and the engine can be reduced. The intake manifold 12 includes a first intake chamber 31b connected to the first intake port and a second intake chamber 32b connected to the second intake port, and controls the flow rate of intake air upstream of the second intake chamber 32b. Since the swirl control valve 36 is arranged, it is possible to generate a swirl in the intake air only by providing one swirl control valve 36 for a plurality of cylinders, which can contribute to a reduction in the number of parts.
[Selection] Figure 1

Description

  The present invention relates to an intake device for a multi-cylinder engine that supplies intake air to an intake port formed in a cylinder head via an intake manifold.

Normally, an intake manifold that supplies intake air to the intake port of a multi-cylinder engine is mounted on the side of the cylinder head where the intake port opens. Japanese Patent Application Laid-Open Publication No. 2004-151542 discloses that the intake manifold is attached to the upper surface of a rocker cover (head cover) fixed to the upper surface of the cylinder head.
JP 2006-189017 A

  By the way, what is described in the above-mentioned Patent Document 1 does not contribute to the reduction of the number of parts because the intake manifold is constituted by a member separate from the rocker cover, and the branch pipe of the intake manifold has an upper surface and a side surface of the rocker cover. Since it is connected to an intake port that passes through the cylinder head and opens to the side surface of the cylinder head, there is a problem that the installation space becomes large and prevents the engine from being downsized.

  The present invention has been made in view of the above-described circumstances, and is intended to reduce the number of parts, the cost, the space, and the engine size as compared with the case where the intake manifold is separately provided outside the head cover. With the goal.

  In order to achieve the above object, according to the first aspect of the present invention, in the intake system of a multi-cylinder engine that supplies intake air to the intake port formed in the cylinder head via the intake manifold, the intake manifold is An intake device for a multi-cylinder engine is proposed, which is integrally formed inside a head cover that covers the upper surface of the cylinder head.

  According to the invention described in claim 2, in addition to the configuration of claim 1, the intake port includes a first intake port and a second intake port, and the intake manifold includes the first intake chamber and the second intake port. An upstream position of the first intake chamber connected to the upstream side of the plurality of first intake ports and an upstream position of the second intake chamber connected to the upstream side of the plurality of second intake ports. An intake device for a multi-cylinder engine is proposed, in which a swirl control valve for controlling the flow rate of intake air is disposed on either one of them.

  According to a third aspect of the present invention, in addition to the configuration of the second aspect, the opening degree of the swirl control valve is continuously changed according to the operating state of the engine. An air intake device is proposed.

  According to a fourth aspect of the present invention, in addition to the structure of any one of the first to third aspects, the fuel injector that directly injects fuel into the combustion chamber connected to the intake port includes a nozzle arm. Is fixed to the cylinder head by abutting a projection of the head on a pivot provided on the head cover and inserting a bolt hole of the nozzle arm into a stud bolt installed in the cylinder head and fastening with a nut. A featured multi-cylinder engine intake system is proposed.

  According to the fifth aspect of the present invention, in addition to the configuration of the fourth aspect, the stud bolt planted in the cylinder head is provided with a seal member that seals the opening of the head cover, and the bolt hole of the nozzle arm. An intake device for a multi-cylinder engine is proposed, which is characterized by being inserted through and fastened with a nut.

  According to the invention described in claim 6, in addition to the configuration of any one of claims 1 to 5, the engine is a V-type engine having an inter-bank space and is supplied from an intercooler. The intake air is bifurcated and flows into the head cover from the inter-bank space side, and then flows into the intake port of the cylinder head from the opposite side of the inter-bank space, and exhausts the inter-bank space side of the cylinder head. An intake device for a multi-cylinder engine is proposed, in which exhaust gases discharged from the ports merge and are supplied to a turbocharger disposed in the inter-bank space.

  According to a seventh aspect of the invention, in addition to the configuration of the second aspect, the engine is a V-type engine having an interbank space, and the fuel is directly injected into the combustion chamber connected to the intake port. A multi-cylinder having an injector, wherein one of the first intake chamber and the second intake chamber is positioned higher than the fuel injector and closer to the inter-bank space of the head cover An engine intake system is proposed.

  The first intake port 35A and the second intake port 35B in the embodiment correspond to the intake port of the present invention.

  According to the first aspect of the present invention, since the intake manifold that supplies intake air to the multi-cylinder engine is integrally formed inside the head cover that covers the upper surface of the cylinder head, the intake manifold is separately provided outside the head cover. Thus, the number of parts, the cost, the space, and the engine can be reduced.

  According to the second aspect of the present invention, the intake manifold includes a first intake chamber connected to the first intake port and a second intake chamber connected to the second intake port, the upstream position of the first intake chamber. Since a swirl control valve for controlling the flow rate of intake air is disposed at one of the upstream positions of the second intake chamber and the swirl for intake by simply providing one swirl control valve for a plurality of cylinders of a multi-cylinder engine. This can contribute to the reduction of the number of parts.

  According to the third aspect of the present invention, since the opening of the swirl control valve is continuously changed according to the operating state of the engine, it is optimal for all operating states such as idling, acceleration, deceleration, and cruise. A combustion state is ensured and it can contribute to reduction of an emission.

  According to the fourth aspect of the present invention, when the fuel injector for directly injecting fuel into the combustion chamber connected to the intake port is fixed to the cylinder head, the projection of the nozzle arm is brought into contact with the pivot provided on the head cover, and the nozzle Since the bolt hole of the arm is inserted into the stud bolt planted in the cylinder head and fastened with a nut, the head cover is fixed to the cylinder head with the fastening force that fixes the fuel injector to the cylinder head, and is integrally formed inside the head cover An axial force for sealing the intake manifold can be applied, and the fastening member for fastening the head cover to the cylinder head can be eliminated or reduced.

  According to the fifth aspect of the present invention, the seal bolt for sealing the opening of the head cover and the bolt hole of the nozzle arm are inserted into the stud bolt implanted in the cylinder head and fastened with the nut. Not only can the sealing member be crushed and three-side sealed to improve sealing performance, but even a cheap sealing material can secure a sufficient sealing effect, which is advantageous in terms of cost.

  According to the sixth aspect of the present invention, the intake air supplied from the intercooler branches into two branches and flows into the head cover from the interbank space side of the V bank, and then from the opposite side of the interbank space to the intake port of the cylinder head. Since the exhaust gas that flows in and is exhausted from the exhaust port on the inter-bank space side of the cylinder head is supplied to the turbocharger arranged in the inter-bank space, the intake air from when the intake air branches into the head cover In addition to minimizing the length of the passage, the turbocharger can be arranged in a compact manner using the inter-bank space.

  According to the seventh aspect of the present invention, one of the first intake chamber and the second intake chamber of the intake manifold is located higher than the fuel injector and closer to the interbank space of the head cover. The space above can be effectively utilized.

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

  1 to 5 show an embodiment of the present invention, FIG. 1 is a perspective view of a V-type engine, FIG. 2 is an enlarged sectional view taken along line 2-2 of FIG. 1, and FIG. 3 is 3-3 of FIG. FIG. 4 is a view of the intake manifold as viewed obliquely from below, and FIG. 5 is a schematic view of the intake system and exhaust system of the engine.

  As shown in FIGS. 1 and 5, a V-type 6-cylinder engine E mounted horizontally in an engine room of an automobile includes a front bank Bf disposed on the front side of the vehicle body and a rear bank Br disposed on the rear side of the vehicle body. A V-shaped interbank space V is formed between the front bank Bf and the rear bank Br. Head covers 13 and 13, in which intake manifolds 12 and 12 are integrally formed, are coupled to the upper surfaces of the cylinder heads 11 and 11 of the front bank Bf and the rear bank Br.

  A turbocharger 14 is mounted on the left side of the inter-bank space V, the front end of an air cleaner 15 disposed above the rear bank Br is connected to the compressor 14a of the turbocharger 14, and a first intake pipe 16 extending from the compressor 14a is connected to the engine. It is connected to the left side surface of the intercooler 17 disposed in front of E. The second intake pipe 18 coming out from the right side surface of the intercooler 17 passes through a throttle valve 19 disposed on the right side surface of the front bank Bf, and then branches into a fork over the inter-bank space V. The intake pipe 20 is connected to the right side surface of the head cover 13 of the front bank Bf, and the other rear intake pipe 21 is connected to the right side surface of the head cover 13 of the rear bank Br.

  The exhaust manifold 22 connected to the exhaust port 26 (see FIG. 2) opened on the rear surface of the cylinder head 11 of the front bank Bf and the front surface of the cylinder head 11 of the rear bank Br merges into one first exhaust pipe 23. It is connected to the turbine 14b of the turbocharger 14 later, and the second exhaust pipe 24 exiting from the turbine 14b is connected to the catalyzer 25. The exhaust ports 26 are opened and closed by exhaust valves 27 (see FIG. 2).

  Next, the structure of the head covers 13 and 13 of the front bank Bf and the rear bank Br will be described with reference to FIGS. Since the head cover 13 of the front bank Bf and the head cover 13 of the rear bank Br are symmetric with respect to the symmetry plane extending in the vehicle width direction, the structure of the head cover 13 of the front bank Bf will be described as a representative.

  The head cover 13 is injection-molded with a synthetic resin, and is composed of two members, a first intake manifold 31 and a second intake manifold 32.

  FIG. 4 shows the first intake manifold 31 and the second intake manifold 32 as core shapes. The first intake manifold 31 includes an L-shaped first intake introduction passage 31a disposed on the right side surface of the head cover 13, a first intake chamber 31b connected to the downstream end of the first intake introduction passage 31a, and a first intake chamber. Three first branch pipes 31c that extend forward from 31b and bend downward are provided. The second intake manifold 32 includes an L-shaped second intake introduction passage 32a disposed on the right side surface of the head cover 13, a second intake chamber 32b connected to the downstream end of the second intake introduction passage 32a, and a second intake chamber. Three second branch pipes 32c extending downward from 32b. The three first branch pipes 31c of the first intake manifold 31 and the three second branch pipes 32c of the second intake manifold 32 are paired with each other, and the intake air connected to the three combustion chambers. Connected to each port.

  As is clear from FIG. 1, the first intake chamber 31 b of the first intake manifold 31 is disposed at a high position (a position far from the cylinder head 11) on the interbank space V side, and the second intake chamber of the second intake manifold 32. 32b is arranged at a low position (position close to the cylinder head 11) opposite to the inter-bank space V.

  As apparent from FIGS. 2 and 5, each of the three combustion chambers 33 of the front bank Bf of the engine E has a first intake port 35A opened and closed by a first intake valve 34A and a second intake valve 34B. Are formed, and the first intake port 35A and the second intake port 35B are connected to the first branch pipe 31c and the second branch pipe 32c, respectively.

  As is apparent from FIG. 5, the inside of the front intake pipe 20 and the rear intake pipe 21 downstream of the throttle valve 19 is partitioned into first intake passages 20a and 21a and second intake passages 20b and 21b. Regarding the intake pipe 20, the downstream end of the first intake passage 20 a is connected to the upstream end of the first intake introduction passage 31 a of the first intake manifold 31, and the downstream end of the second intake passage 20 b is connected to the second intake manifold 32. Connected to the upstream end of the second intake introduction passage 32a. A swirl control valve 36 is disposed in the second intake introduction passage 32 a of the second intake manifold 32.

  As is apparent from FIGS. 2 and 3, a fuel injector 37 for injecting fuel into each combustion chamber 33 is provided on the upper surface of the cylinder head 11, and the fuel injector 37 is formed on the top surface of the head cover 13. It protrudes upward through the annular seal member 41 mounted in the opening 13a. The nozzle arm 42 that presses the fuel injector 37 protruding upward from the top surface of the head cover 13 and fixes it to the cylinder head 11 has a bolt hole 42a penetrating in the vertical direction at the middle portion thereof, and is directed downward at the tip portion thereof. A protrusion 42b is provided. On the other hand, a stat bolt 38 is planted on the upper surface of the cylinder head 11, and the stat bolt 38 has an annular seal member 39 attached to an opening 13 b formed on the top surface of the head cover 13 and a bolt hole of the nozzle arm 42. 42a and extending above the head cover 13. The head cover 11 is provided with a pivot 43 with which the protrusion 42b of the nozzle arm 42 abuts from above.

  Accordingly, when the nut 40 is tightened from the upper end of the stat bolt 38, the fuel injector 37 pushed down together with the nozzle arm 42 by the nut 40 is fixed to the cylinder head 11, and at the same time, the protrusion 42b at the tip of the nozzle arm 42 is fixed. The head cover 13 with the pivot 43 pushed down is fixed to the upper surface of the cylinder head 11. At this time, since the seal member 39 attached to the opening 13b of the head cover 13 is crushed by the lower surface of the nozzle arm 37a, three-side sealing is possible, and the opening 13b of the head cover 13 can be reliably sealed. As described above, the opening 13b of the head cover 13 is surely sealed with respect to the upper surface of the cylinder head 11, so that the first and second intake manifolds 31 and 32 integrally formed inside the head cover 13 are simultaneously sealed. Can do.

  Next, the operation of the embodiment of the present invention having the above configuration will be described.

  When the engine E is operated, the exhaust gas discharged from the six exhaust ports 26 of the front bank Bf and the rear bank Br to the front and rear exhaust manifolds 22 and 22 gathers in the first exhaust pipe 23 and enters the turbine 14b of the turbocharger 14. Supplied. When the turbine 14b of the turbocharger 14 is rotated by the energy of the exhaust gas, the compressor 14a coupled coaxially with the turbine 14b rotates, compresses the intake air that has exited the air cleaner 15, and supplies the compressed air to the first intake pipe 16. Since the intake air compressed by the compressor 14a has risen in temperature, the intake air is cooled by the intercooler 17 in order to increase the charging efficiency, and then passes through the throttle valve 19 provided in the second intake pipe 18 and then bifurcates. Then, it is supplied to the front intake pipe 20 and the rear intake pipe 21.

  For example, the intake air supplied to the front intake pipe 20 is branched into a first intake passage 20a and a second intake passage 20b partitioned inside the front intake pipe 20, and formed inside the head cover 13 of the front bank Bf. Are supplied to the first intake manifold 31 and the second intake manifold 32 of the intake manifold 12, respectively. The intake air supplied to the first intake manifold 31 branches from the first intake introduction passage 31a through the first intake chamber 31b into three first branch pipes 31c, and the first intake air formed in the cylinder head 11 therefrom. It is supplied to the three combustion chambers 33 through the ports 35A. The intake air supplied to the second intake manifold 32 of the intake manifold 12 branches from the second intake introduction passage 32a to the three second branch pipes 32c through the second intake chamber 32b and from there to the cylinder head 11. It is supplied to the three combustion chambers 33 through the formed second intake ports 35B.

  At this time, according to the operating state of the engine E, for example, the opening degree of the swirl control valve 36 provided in the second intake introduction passage 32a is controlled according to idling, acceleration, deceleration, and cruise. As a result, the ratio of the intake air amount supplied to the second intake port 35B to the intake air amount supplied to the first intake port 35A is changed, and the size of the swirl generated in the combustion chamber 33 is controlled, whereby the engine E Thus, it is possible to secure the optimum combustion state in all the operating states and contribute to the reduction of emissions. Further, since one swirl control valve 36 is provided for the three combustion chambers 33 of the front bank Bf, it is possible to contribute to a reduction in the number of parts.

  The flow of the intake air supplied to the front intake pipe 20 has been described above, but the same applies to the flow of intake air supplied to the rear intake pipe 21.

  Since the intake manifold 12 for supplying intake air to the front bank Bf and the rear bank Br of the engine E is formed integrally in the head cover 13 that covers the upper surface of the cylinder head 11, the intake manifold 12 is separately provided outside the head cover 13. Compared with the case where the body is provided, the number of parts, the cost, the space, and the engine can be reduced.

  The intake air supplied from the intercooler 17 is bifurcated and flows into the head covers 13 and 13 of the front bank Bf and the rear bank Br from the interbank space V, and then from the opposite side of the interbank space V to the cylinder heads 11 and 11. The exhaust gas flowing into the first and second intake ports 35A, 35B, and exhausted from the exhaust ports 26 on the inter-bank space V side of the cylinder heads 11, 11 is sent to the turbocharger 14 disposed in the inter-bank space V. Since the intake air is supplied, the length of the intake passage from when the intake air bifurcates from the second intake pipe 18 to the front intake pipe 20 and the rear intake pipe 21 until it flows into the head covers 13 and 13 is minimized. In addition, the turbocharger 14 can be arranged in a compact manner using the inter-bank space V.

  Of the first intake chamber 31 b of the first intake manifold 31 and the second intake chamber 32 b of the second intake manifold 32 provided on the head cover 13, one of the first intake chambers 31 b is positioned higher than the fuel injector 37. Since the head cover 13 is provided near the inter-bank space V, the space above the inter-bank space V can be used effectively.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various design changes can be made without departing from the present invention described in the claims. Is possible.

  For example, although the V-type 6-cylinder engine E is illustrated in the embodiment, the present invention can be applied to any type of multi-cylinder engine in which two or more cylinders are juxtaposed in a cylinder block.

  In addition, if a swirl control valve is provided immediately upstream of the merging portion of the two second intake passages 20b and 21b, the number of swirl control valves can be reduced to one, thereby further reducing the cost.

Perspective view of V-type engine 2-2 line enlarged sectional view of FIG. 3-3 line enlarged view of FIG. View of intake manifold from diagonally below Schematic diagram of engine intake and exhaust systems

Explanation of symbols

11 Cylinder head 12 Intake manifold 13 Head cover 13b Opening 17 Intercooler 26 Exhaust port 31b First intake chamber 32b Second intake chamber 35A First intake port (intake port)
35B 2nd intake port (intake port)
36 Swirl control valve 37 Fuel injector 38 Stud bolt 39 Seal member 40 Nut 42 Nozzle arm 42a Bolt hole 42b Projection 43 Pivot E Engine V Inter-bank space

Claims (7)

In a multi-cylinder engine intake device that supplies intake air to intake ports (35A, 35B) formed in a cylinder head (11) via an intake manifold (12),
An intake device for a multi-cylinder engine, wherein the intake manifold (12) is integrally formed inside a head cover (13) that covers an upper surface of the cylinder head (11).   The intake port (35A, 35B) includes a first intake port (35A) and a second intake port (35B), and the intake manifold (12) includes a first intake chamber (31b) and a second intake chamber (32b). The first intake chamber (31b) connected to the upstream side of the plurality of first intake ports (35A) and the upstream position connected to the upstream side of the plurality of second intake ports (35B). The multi-cylinder engine intake device according to claim 1, wherein a swirl control valve (36) for controlling a flow rate of intake air is disposed at any one of upstream positions of the two intake chambers (32b).   The intake device for a multi-cylinder engine according to claim 2, wherein the opening degree of the swirl control valve (36) is continuously changed according to the operating state of the engine (E).   The fuel injector (37) for directly injecting fuel into the combustion chamber (33) connected to the intake port (35A, 35B) has a pivot (43) provided with a protrusion (42b) of the nozzle arm (42) on the head cover (13). And the bolt hole (42a) of the nozzle arm (42) is inserted into a stud bolt (38) planted in the cylinder head (11) and fastened with a nut (40). The intake device for a multi-cylinder engine according to any one of claims 1 to 3, wherein the intake device is fixed to a head (11).   The stud bolt (38) planted in the cylinder head (11) is provided with a seal member (39) for sealing the opening (13b) of the head cover (13) and a bolt hole (42a) of the nozzle arm (42). The intake device for a multi-cylinder engine according to claim 4, wherein the intake device is inserted and fastened with a nut (40).   The engine (E) is a V-type engine having an inter-bank space (V), and the intake air supplied from the intercooler (17) branches into two branches and enters the head cover (13) from the inter-bank space (V) side. Then, the air flows into the intake port (35A, 35B) of the cylinder head (11) from the opposite side to the inter-bank space (V), and on the inter-bank space (V) side of the cylinder head (11). The exhaust gas discharged from the exhaust port (26) joins and is supplied to the turbocharger (14) disposed in the inter-bank space (V). The intake device for a multi-cylinder engine according to item 1.   The engine (E) is a V-type engine having an interbank space (V), and includes a fuel injector (37) that directly injects fuel into a combustion chamber (33) connected to the intake port (35A, 35B). One of the first intake chamber (31b) and the second intake chamber (32b) is higher than the fuel injector (37) and close to the inter-bank space (V) of the head cover (13). The multi-cylinder engine intake device according to claim 2, wherein the intake device is in a position.

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