JP2007285171A - Intake pipe mounting structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an intake pipe mounting structure capable of increasing the mass flow of air to be sucked in a combustion chamber. <P>SOLUTION: The intake pipe mounting structure comprises a resin-made intake pipe 21 connected to an intake port formed in a cylinder head 12 of an internal combustion engine 10, and an insertion part which is integrally formed of a resin at an outlet of the intake pipe 21 and inserted inside the intake port. The length of a path by the intake port of the cylinder head 12 out of the air distribution path from the intake pipe 21 to a combustion chamber 20 can be reduced by the length of the resin-made insertion part. Thus, the temperature rise of the air flowing into the intake port from the intake pipe 21 is reduced, and the air volume expansion is reduced. Accordingly, the mass flow of the air sucked in the combustion chamber 20 can be increased. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an intake pipe mounting structure connected to an intake port of a cylinder head.

  2. Description of the Related Art A port injection type fuel injection valve that injects fuel into air sucked into a combustion chamber of an internal combustion engine is widely known (see, for example, Patent Document 1). Conventionally, this type of fuel injection valve is attached to the upper side of the intake port 16 formed in the cylinder head 12 that houses the intake valve 40, as shown in FIG. A resin intake pipe 210 is attached to the inlet 161 of the intake port 16.

JP 2004-44459 A

Here, while the intake pipe 210 is made of resin, the cylinder head 12 is generally made of metal such as aluminum. The cylinder head 12 is heated to a high temperature (for example, 80 ° C. to 90 ° C.) by the heat of the combustion chamber 20, whereas the intake pipe 210 is made of resin so that the temperature rise is small and the temperature is almost equal to the atmospheric temperature Often. Therefore, when the air at the atmospheric temperature flowing through the intake pipe 210 flows into the intake port 16 of the cylinder head 12, the temperature rises and the volume expands. As a result, there is a problem that the mass flow rate of the air sucked into the combustion chamber 20 is reduced and the output of the internal combustion engine is reduced.
SUMMARY OF THE INVENTION An object of the present invention is to provide an intake pipe attachment structure that increases the mass flow rate of air sucked into a combustion chamber.

  The intake pipe mounting structure according to any one of claims 1 to 7, further comprising an insertion portion that is integrally formed with resin at an outlet of the intake pipe and is inserted into the cylinder head from the inlet of the intake port. Therefore, the length of the path by the intake port of the cylinder head in the air flow path from the intake pipe to the combustion chamber can be shortened by the resin insertion portion. Therefore, the temperature of the air flowing into the intake port from the intake pipe is reduced and the volume expansion is reduced. Therefore, the mass flow rate of the air sucked into the combustion chamber can be increased.

  According to the invention of claim 2, since the fuel injection valve is attached to the intake pipe, the fuel injection valve is attached to the intake pipe in advance before connecting the intake pipe to the intake port of the cylinder head. I can leave. Alternatively, the fuel injection valve and the intake pipe can be integrally formed by, for example, insert molding. Therefore, it is not necessary to separately assemble the fuel injection valve and the intake pipe to the cylinder head when assembling the parts to the cylinder head, and the intake pipe with the fuel injection valve attached is assembled to the cylinder head. You can Therefore, the workability of assembling the parts to the cylinder head can be improved.

  Here, in the conventional structure shown in FIG. 5, a portion of the cylinder head to which the fuel injection valve is attached (a portion indicated by reference numeral 121) is formed in a shape extending substantially perpendicular to the direction of attachment of the fuel injection valve. . Therefore, the flow path cross section of the intake port of the portion adjacent to the downstream side of the air flow of the fuel injection valve (portion indicated by P2) is the portion of the portion adjacent to the upstream side of the air flow of the fuel injection valve (portion indicated by P1). It is larger than the cross section of the channel. Therefore, since the vortex is generated in the air flow at the portion where the flow path cross section is enlarged, smooth intake cannot be performed, and the mass flow rate of the air sucked into the combustion chamber is reduced. If the portion 121 of the cylinder head to which the fuel injection valve is attached is formed in a shape extending in the direction along the air flow in the intake port to avoid the enlargement of the cross section of the flow path, the cylinder head is made of metal. Therefore, the workability of the portion 121 to which the fuel injection valve is attached is deteriorated.

  On the other hand, in the invention according to claim 3 in which the fuel injection valve is attached to the resin-made intake pipe, the flow passage cross-sectional shape of the intake pipe includes a portion adjacent to the upstream side of the air flow of the fuel injection valve and the fuel injection valve. It is substantially the same in the part adjacent to the air flow downstream side of the valve. Therefore, the generation of entrained vortices can be reduced and smooth intake can be performed, and as a result, the mass flow rate of air drawn into the combustion chamber can be increased.

  In the invention according to claim 6, the intake pipe is opened and closed by switching between a tubular body having an intake passage therein, a partition wall that partitions the intake passage into a first passage and a second passage, and a first passage and a second passage. Opening and closing means. Therefore, when assembling the parts to the cylinder head, the intake pipe provided with the partition wall and the opening / closing means can be assembled to the cylinder head. Therefore, the workability of assembling the parts to the cylinder head can be improved as compared with the case where the partition wall and the opening / closing means are configured separately from the intake pipe.

  In the invention according to claim 7, the injection direction of the fuel injected from the fuel injection valve is the direction toward the partition wall. Therefore, the fuel injected from the fuel injection valve collides with the partition wall and is atomized, so that a good air-fuel mixture can be obtained.

Hereinafter, a plurality of embodiments of the present invention will be described with reference to the drawings.
(First embodiment)
1 and 2 show an internal combustion engine to which an intake pipe mounting structure according to a first embodiment of the present invention is applied. The internal combustion engine 10 is, for example, a gasoline internal combustion engine that uses gasoline as fuel. The fuel may be alcohol, for example. The internal combustion engine 10 is not limited to a gasoline internal combustion engine, and may be a diesel internal combustion engine, for example.

  The internal combustion engine 10 includes a cylinder block 11 and an aluminum cylinder head 12. The cylinder block 11 forms a cylindrical cylinder 13. The internal combustion engine 10 has a cylinder 13, and the cylinder 13 accommodates a piston 14 inside. The piston 14 is reciprocated in the axial direction of the cylinder 13 by the connecting rod 15. In the present embodiment, a plurality of pistons 14 are provided, but one may be used.

  The cylinder head 12 is disposed on one end side of the cylinder block 11. The cylinder head 12 forms an intake port 16 (see FIG. 2) and an exhaust port 17. The internal combustion engine 10 includes an intake valve 40 that opens and closes the intake port 16 through the cylinder head 12 and an exhaust valve 50 that opens and closes the exhaust port 17.

  The upper end portion of the intake valve 40 is in contact with the intake cam 45 with the tappet 44 interposed therebetween. A spring 47 as an elastic member is installed between the cylinder head 12 and the tappet 44. The spring 47 presses the tappet 44 in a direction away from the cylinder head 12. The tappet 44 moves integrally with the intake valve 40. For this reason, the spring 47 presses the intake valve 40 in the closing direction.

  The upper end portion of the exhaust valve 50 is in contact with the exhaust cam 55 with the tappet 54 interposed therebetween. A spring 57 as an elastic member is installed between the cylinder head 12 and the tappet 54. The spring 57 presses the tappet 54 in a direction away from the cylinder head 12. The tappet 54 moves integrally with the exhaust valve 50. Therefore, the spring 57 presses the exhaust valve 50 in the closing direction.

  An inner wall surface 111 of the cylinder block 11 forming the cylinder 13, a surface of the cylinder head 12 on the cylinder block 11 side, an end surface of the piston 14 on the cylinder head 12 side, an end surface of the intake valve 40 on the piston 14 side, A space formed by the end face on the piston 14 side of the exhaust valve 50 is the combustion chamber 20. The combustion chamber 20 can communicate with the intake port 16 and the exhaust port 17. Communication between the combustion chamber 20 and the intake port 16 is opened and closed by an intake valve 40. Communication between the combustion chamber 20 and the exhaust port 17 is opened and closed by an exhaust valve 50.

  An ignition device 60 is installed in a substantially central portion of the combustion chamber 20 in the cylinder head 12. In the ignition device 60, an ignition coil (not shown) and an ignition plug are integrally formed. The ignition device 60 has an end on the spark plug side exposed to the combustion chamber 20.

  A resin intake pipe 21 is connected to an inlet 161 (see FIG. 2) of the intake port 16, and an intake passage 22 formed by the intake pipe 21 communicates with the intake port 16. The intake pipe 21 is provided for each of the plurality of cylinders 13, and the plurality of intake pipes 21 constitute intake manifolds that are integrally formed of resin. The end of the intake pipe 21 opposite to the combustion chamber 20 is connected to an intake inlet (not shown). The air introduced from the intake air introduction portion is supplied to the intake port 16 from the intake passage 22 formed by the intake pipe 21 via, for example, an air cleaner, a throttle 211 and a surge tank 212 (not shown).

  An injector 70 as a fuel injection valve that injects fuel into the air sucked into the intake port 16 is attached to an upper portion of the outlet 23 of the intake pipe 21. The intake pipe 21 is divided into upper and lower parts and is resin-molded. The injector 70 and the fuel rail 72 are attached to the upper divided body 213 of the upper divided body 213 and the lower divided body 214 of the intake pipe 21. The upper divided body 213 and the lower divided body 214 are joined by welding. In addition, it may replace with welding and may couple | bond with fastening means, such as a clip which is not illustrated, or an adhesive agent.

In the injector 70, one end 71 in the axial direction is exposed to the intake passage 22 of the intake pipe 21, and the other end is connected to the fuel rail 72. The injector 70 has a nozzle hole (not shown) at the end opposite to the fuel rail 72. The injector 70 is formed integrally with the resin intake pipe 21 by insert molding. The fuel rail 72 is made of resin and is formed integrally with the intake pipe 21.
Here, the configuration of the injector 70 will be described. The injector 70 includes a valve member (not shown) that opens and closes the nozzle hole, a movable core (not shown) that reciprocates together with the valve member, and a nozzle hole of the movable core. A fixed core (not shown) installed opposite to the movable core on the opposite side, a spring (not shown) that applies a load to the valve member toward one of the reciprocating directions, and a spring load that is energized A coil (not shown) that generates a magnetic force for attracting the movable core to the fixed core against the above, and a casing that houses at least one of the valve member, the movable core, the fixed core, the spring, and the coil therein. Prepare.

  Fuel is supplied to the fuel rail 72 from a fuel tank (not shown). The injector 70 injects the fuel supplied to the fuel rail 72 into the air flowing through the intake passage 22 of the intake pipe 21 from the injection hole. The injector 70 intermittently injects fuel by an electrical signal output from an ECU (not shown). That is, the injector 70 is an electromagnetic valve that electrically interrupts fuel injection.

  The cross-sectional shape of the intake passage 22 formed by the intake pipe 21 includes a portion adjacent to the upstream side of the air flow of the injector 70 (a portion indicated by reference numeral P1) and a portion adjacent to the downstream side of the air flow of the injector 70 (reference number P2). Are substantially the same. An insertion portion 24 (see FIG. 2) is integrally formed of resin at the outlet 23 portion of the intake pipe 21. The insertion portion 24 has a shape extending in an annular shape. The insertion portion 24 is inserted into the intake port 16 from the inlet 161 of the intake port 16.

  On the outer peripheral surface of the intake pipe 21, a locking portion 25 (see FIG. 2) that protrudes radially outward is integrally formed of resin. The locking portion 25 has a shape extending along the circumferential direction of the intake pipe 21 except for a portion to which the injector 70 is attached. When the insertion portion 24 is inserted into the intake port 16, the locking portion 25 comes into contact with the outer surface of the cylinder head 12, and the insertion amount of the insertion portion 24 is limited.

  As described above, according to the first embodiment, the injector 70 is attached to the intake pipe 21 connected to the cylinder head 12. Therefore, the downstream end portion of the intake pipe 21 is located on the downstream side of the attachment position of the injector 70. Therefore, the length of the path formed by the resin-made intake pipe 21 among the air flow paths from the intake pipe 21 to the combustion chamber 20 can be increased. The length of the route can be shortened. Therefore, the temperature of the air flowing into the intake port 16 from the intake pipe 21 is reduced and the volume expansion is reduced. Therefore, the mass flow rate of the air sucked into the combustion chamber 20 can be increased.

  Further, according to the first embodiment, the injector 70 and the fuel rail 72 are formed integrally with the intake pipe 21. Therefore, it is not necessary to individually assemble the injector 70, the fuel rail 72, and the intake pipe 21 to the cylinder head 12 when performing the operation of assembling various components to the cylinder head 12. That is, the intake pipe 21 to which the injector 70 and the fuel rail 72 are attached can be assembled to the cylinder head 12. Therefore, the workability of assembling parts to the cylinder head 12 can be improved.

  Here, in the development stage of the internal combustion engine 10, the injector 70 and the intake pipe 21 are separated from each other as in the prior art when optimal adjustment is made between various elements that determine the spray state of the injector 70 and the shape of the intake port 16. If it is a body, the workability of the adjustment work is poor. On the other hand, according to the first embodiment, since the injector 70 is formed integrally with the intake pipe 21, workability of the adjustment work can be improved.

  Further, according to the first embodiment, the outlet 23 of the intake pipe 21 is provided with the insertion portion 24 that is inserted into the cylinder head 12. Therefore, the length of the path by the intake port 16 of the cylinder head 12 in the air flow path from the intake pipe 21 to the combustion chamber 20 can be shortened by the resin insertion portion 24. Therefore, the temperature of the air flowing into the intake port 16 from the intake pipe 21 is reduced and the volume expansion is reduced. Therefore, the mass flow rate of the air sucked into the combustion chamber 20 can be increased.

(Second Embodiment)
A second embodiment of the present invention is shown in FIG. In addition, the same code | symbol is attached | subjected to the component same as 1st Embodiment, and description is abbreviate | omitted.
In the case of the second embodiment, the intake pipe 21 includes a pipe body 261 having an intake passage 22 therein, a partition wall 26 that divides the intake passage 22 into upper and lower portions, and a plate as an opening / closing means that switches between the upper and lower flow passages. The door 27 and the rotating shaft 28 provided on the plate door 27 are provided. The tubular body 261, the partition wall 26, the plate door 27, and the rotating shaft 28 are made of resin, and the partition wall 26 is formed integrally with the tubular body 261.

  When the plate door 27 is rotated to the solid line position in FIG. 2, the lower flow path is closed, and when the plate door 27 is rotated to the alternate long and short dash line position, both the upper flow path and the lower flow path are opened. When rotating, the upper flow passage is closed. By controlling the rotation of the plate door 27 in this way, the flow of air flowing into the combustion chamber 20 is changed according to the traveling state of the vehicle.

  The injector 70 and the partition wall 26 are arranged so that the injection direction of fuel injected from the injector 70 (the direction indicated by the arrow L1 in FIG. 3) is the direction toward the partition wall 26. In other words, the axial direction L1 of the injector 70 intersects the partition wall 26. Therefore, since the fuel injected from the injector 70 collides with the partition wall 26 and is atomized, a good air-fuel mixture can be obtained.

  The rotating shaft 28 is rotatably supported between the upper divided body 213 and the lower divided body 214 of the intake pipe 21. Specifically, the rotating shaft 28 is stored in a recess (not shown) formed on the dividing surfaces of the upper divided body 213 and the lower divided body 214. Therefore, it can be avoided that the rotary shaft 28 becomes a resistance of the air flowing through the intake passage 22.

(Third embodiment)
A third embodiment of the present invention is shown in FIG. In addition, the same code | symbol is attached | subjected to the component same as 1st Embodiment and 2nd Embodiment, and description is abbreviate | omitted.
In the second embodiment, the injection direction L1 of the fuel injected from the injector 70 is the direction toward the partition wall 26, whereas in the third embodiment, the injection direction of the fuel injected from the injector 70 (in FIG. 4) The injector 70 and the partition wall 26 are arranged so that the direction indicated by the arrow L2 is shifted from the partition wall 26. In other words, the axial direction L2 of the injector 70 intersects with the outlet 23 of the intake pipe 21, and the partition wall 26 is disposed on the upstream side of the air flow with respect to the axial direction L2 of the injector 70. Therefore, air can be made to flow into the combustion chamber 20 with a strong airflow.

(Other embodiments)
In the first embodiment described above, the injector 70 is formed integrally with the resin intake pipe 21 by insert molding. However, the injector 70 is resin-molded separately from the intake pipe 21 and is provided in the intake pipe 21. The injector 70 may be attached to the intake pipe 21 by inserting the injector 70 into the hole.
In the first embodiment described above, the fuel rail 72 is made of resin, but may be made of metal. In that case, it is desirable to form the fuel rail 72 integrally with the resin intake pipe 21 by insert molding.
In the first embodiment described above, the fuel rail 72 is formed integrally with the intake pipe 21 together with the injector 70. However, the fuel rail 72 may be disposed at a position where it does not contact the intake pipe 21 and provided separately.

  In the first embodiment described above, the entire injector 70 is disposed inside the thickness of the intake pipe 21, but a part (for example, the upper part) of the injector 70 may be exposed outside the thickness of the intake pipe 21. .

  The locking part 25 in the first embodiment described above has a shape extending along the circumferential direction of the intake pipe 21 except for a part to which the injector 70 is attached. However, the locking part 25 includes a part to which the injector 70 is attached. The shape may extend annularly.

The cylinder head 12 according to the first embodiment described above has one intake port 16 for one combustion chamber 20, but a plurality of (for example, two) intake ports 16 for one combustion chamber 20. The present invention may be applied to the internal combustion engine 10 having the following. In that case, each of the plurality of intake ports 16 may be provided with an injector 70, or fuel injected from one injector 70 may be distributed to the plurality of intake ports 16.
As described above, the present invention is not limited to the above-described embodiment, and can be applied to various embodiments without departing from the gist thereof.

1 is a cross-sectional view schematically showing an internal combustion engine according to a first embodiment of the present invention. Sectional drawing which shows typically the attachment structure of the intake pipe of FIG. Sectional drawing which shows typically the attachment structure of the intake pipe by 2nd Embodiment of this invention. Sectional drawing which shows typically the attachment structure of the intake pipe by 3rd Embodiment of this invention. Sectional drawing which shows the outline of the conventional internal combustion engine.

Explanation of symbols

  10: internal combustion engine (internal combustion engine), 12: cylinder head, 16: intake port, 20: combustion chamber, 21: intake pipe, 22: intake passage, 23: outlet of intake pipe, 24: insertion section, 70: injector ( Fuel injection valve).

Claims (7)

A resin intake pipe connected to an intake port formed in a cylinder head of the internal combustion engine;
An insertion portion that is integrally formed with resin at the outlet of the intake pipe and is inserted into the intake port from the inlet of the intake port;
An intake pipe mounting structure comprising: A fuel injection valve for injecting fuel into the air sucked into the intake port;
The intake pipe attachment structure according to claim 1, wherein the fuel injection valve is attached to the intake pipe.   The flow passage cross-sectional shape of the intake pipe is substantially the same in a portion adjacent to the cylinder head side of the fuel injection valve and a portion adjacent to the opposite side of the cylinder head of the fuel injection valve. Intake pipe mounting structure.   The intake pipe mounting structure according to claim 2 or 3, wherein a plurality of the fuel injection valves are provided for each combustion chamber of the internal combustion engine. The fuel injection valve has a resin casing,
The intake pipe mounting structure according to any one of claims 2 to 4, wherein the casing is integrally formed with the intake pipe and resin. The intake pipe is
A tube having an intake passage inside;
A partition partitioning the intake passage into a first passage and a second passage;
Opening and closing means for switching between the first passage and the second passage;
An intake pipe mounting structure according to any one of claims 1 to 5, further comprising: The intake pipe mounting structure according to claim 6, wherein an injection direction of fuel injected from the fuel injection valve is a direction toward the partition wall.

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