JP2002106428A - Intake manifold of engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an intake manifold reducing vibrations undergone by an injector and a delivery pipe and enhancing the assembly properties of a cylinder head and a head mounting flange. SOLUTION: In the mounting flange 13 of the intake manifold 8, a plurality of cylinder head mounting bosses 28 are formed in such a manner as to be located around adjacent branch openings 13e, 13f and 13g, and a plurality of delivery pipe fixing bosses 27 are formed in such a manner as to be located between the adjacent bosses 28. The rigidity of the bosses 27 can be enhanced, and the vibrations undergone by the injector 15 and the delivery pipe 17 can be reduced. Additionally, a gasket formed integrally with a surface part for blocking an opening for cooling water is mounted between the cylinder head and the mounting flange 13 for the purpose of enhancing the assembly properties of the intake manifold 8.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a motor vehicle and others.
The present invention relates to an intake manifold for an engine applicable to an engine having a plurality of cylinders.

[0002]

2. Description of the Related Art An engine for an automobile or the like is provided with an intake manifold for guiding an air-fuel mixture to a combustion chamber and an exhaust manifold for discharging exhaust gas after combustion to the outside. Since the temperature of the air-fuel mixture passing through the inside of the intake manifold is not higher than that of the exhaust manifold, the intake manifold made of a synthetic resin is increasing in place of the conventional cast iron intake manifold.

FIG. 12 shows a part of an intake manifold 8 of a multi-cylinder engine. A head mounting flange 13 is connected to a distal end of the branch 8a of the intake manifold 8. The head mounting flange 13 is connected to the cylinder head 6 with bolts 14 and is connected to an intake port (not shown). When the engine 1 is of a fuel injection type, an injector (fuel injector) 15 is mounted near the tip of the intake manifold 8, and a delivery pipe 17 connected to a head of the injector 15 is connected to a boss via a stay 18. 19 support. This boss 1
9 is provided on the branch 8 a of the intake manifold 8 (the same applies to other branches) at a position away from the head mounting flange 13.
Is used to fix the base of the stay 18.

Referring to the cylinder head 6, FIG. 13 shows a flange surface 21 formed so as to protrude from the cylinder head 6 in a three-cylinder engine. Each of the three flange surfaces 21 has an opening 21a communicating with the branch 8a. Also, reference numeral 2
1b is a bolt hole for connecting the head mounting flange 13. Here, one flange surface 21 has holes 2 for cooling water.
1c is formed to open. This cooling water hole 2
1c is formed for machining a cooling water passage inside the cylinder head 6, and includes a head mounting flange 1c.
After attaching 3 to the cylinder head 6, it is necessary to close it.

Next, FIG. 14 shows a state where a gasket 22 is mounted on the flange surface 21. This gasket 22
Is a so-called O-ring type, and has a seal portion 22a surrounding the periphery of the opening 21a of the flange surface 21 of the cylinder head 6. Opening 21a
Are connected by a connecting portion 22b to facilitate the work of mounting the gasket 22.
A seal portion 22c surrounding the cooling water hole 21c is formed integrally with a part of the gasket 22 corresponding to the cooling water hole 21c. Also, FIG.
4 shows a state where the gasket 22 shown in FIG. 4 is mounted on the conventional head mounting flange 13 side. The head mounting flange 13 is formed with a lightened portion 13a for weight reduction, and the connecting portion 22b of the gasket 22 is disposed on the lightened portion 13a so as to be separated from the flange surface of the head mounting flange 13. ing. (DD of FIG. 15)
FIG. 16 showing a cross section).

FIG. 17 shows another conventional head mounting flange. A bridge 13b is formed by bridging a lightening portion 13a to the head mounting flange 13.
The head mounting flange 13 is reinforced (E- in FIG. 17).
(See FIG. 18 showing E section). In the case of this head mounting flange, as shown in FIG. 18, which shows a cross section taken along line EE in FIG. 17, the connecting rib 13b protrudes, so that the gasket 22 does not have the connecting portion 22b (see FIG. 15). Will be used. In this case as well, one gasket 22 has a sealing portion 2 surrounding the cooling water hole 21c.
2c is formed integrally. 15 and FIG.
Is a hole through which a bolt for fixing the head mounting flange 13 to the cylinder head 6 is inserted.

In the head mounting flanges shown in FIGS. 15 to 18, the cooling water hole 21c provided on the flange surface 21 is surrounded by the seal portion 22c of the gasket 22 (FIG. 14). 19) showing the FF cross section of FIG. 17 and the pressure of the cooling water is directly received by the end face 13d of the head mounting flange 13, as indicated by the thick arrow. For this reason, the head mounting flange 13
It is necessary to select a material having water resistance as a material that can be used for manufacturing the slab.

On the other hand, Japanese Patent Laid-Open No. 2000-73 discloses a prior art relating to measures against vibration of the injector and the delivery pipe.
Japanese Patent Application Publication No. 910 discloses a boss provided on a flange portion of an intake manifold, and an injector and a delivery pipe are mounted on the boss to support the boss, thereby improving vibration resistance.

Further, as prior art relating to gaskets, Japanese Patent Application Laid-Open No. 2000-46193 and Japanese Utility Model Application Laid-Open No.
There is one disclosed in Japanese Patent No. 7656. The former gasket is formed by sandwiching a rubber elastic body between two mounting plates, and the latter gasket is designed so that the entire shape of the gasket is devised so that the stacked gasket is not caught when the gasket is taken out. I have to.

[0010]

The engine vibrates during operation, and the vibration acceleration increases as the distance from the cylinder head increases. Therefore, in the conventional mounting structure of the injector and the delivery pipe, another vibration reducing mechanism, For example, it is necessary to take other measures such as increasing the thickness of the intake manifold or adding a reinforcing component.

The head mounting flange 13 shown in FIG.
Since the seal portions 22a are connected to each other, the gasket 22 can be easily mounted, but the strength may not be sufficient. On the other hand, the head mounting flange 13 shown in FIG. 17 is reinforced by the bridge 13b. In addition, while having sufficient strength, since the seal portions are independent of each other, it takes time and effort to mount the gasket 22, which has advantages and disadvantages.

[0015] In the conventional head mounting flange 13 shown in FIGS. 15 to 18, a hole 21 c for cooling water provided on a flange surface 21 is formed by a sealing portion 22 c of a gasket 22.
19, the water pressure of the cooling water is applied to the head mounting flange 1 as shown by the bold arrow in FIG.
3 is received directly on the end face 13d, and the material that can be used to manufacture the head mounting flange 13 is limited to a water-resistant material.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and has an injector and a delivery pipe mounting structure having excellent vibration resistance, as well as improved assemblability between a cylinder head and a head mounting flange. It is an object of the present invention to provide an intake manifold having a reduced intake manifold.

[0014]

According to the present invention, a plurality of openings connected to a plurality of intake ports provided in a cylinder head are provided as means for solving the above-mentioned problems. And a head mounting flange mounted on the cylinder head, and an intake manifold of an engine provided with a plurality of branch pipes connected to the head mounting flange, wherein the head mounting flange is adjacent to a delivery pipe fixing boss. A plurality of cylinder head mounting bosses are provided between the openings, and the delivery pipe fixing boss is formed between the plurality of cylinder head mounting bosses and disposed between the plurality of openings. It is characterized by.

In this configuration, a boss for fixing the delivery pipe is formed between the cylinder head mounting boss, which is a portion formed in the thick portion of the head mounting flange and directly fixed to the cylinder head. In addition, the rigidity of the portion where the delivery pipe fixing boss is formed is improved, and the vibration can be reduced.

Next, in the second aspect of the present invention, in the first aspect, the delivery pipe fixing boss has a longitudinal direction from the engine with respect to the axis of the cylinder provided on the cylinder head. It is characterized in that it is formed to be inclined so as to be separated.

As described above, by inclining the longitudinal direction of the delivery pipe fixing boss with respect to the axis of the cylinder so as to be separated from the engine, the delivery pipe fixing boss can be separated from the side of the engine. The delivery pipe can be easily attached and detached even when the intake manifold is attached to the head. In particular, in the case of a DOHC engine in which the upper portion of the cylinder head protrudes outward, a delivery pipe fixing boss can be formed so as to avoid this overhang.

According to the third aspect of the present invention, there is provided an opening connected to an intake port provided in the cylinder head, a head mounting flange mounted on the cylinder head, and a head mounting flange connected to the head mounting flange. In an intake manifold of an engine provided with a plurality of branch pipes, the head mounting flange includes a connecting rib between adjacent openings and a lightening portion around the connecting rib, and a groove is formed in the connecting rib. And a joint portion of a gasket in which a plurality of seal portions are joined at a joint portion is fitted in the groove.

According to this configuration, as a substitute for the lightening portion provided for reducing the weight, the connecting portion of the gasket is fitted in the groove formed in the connecting rib formed for reinforcement, thereby providing the head mounting flange. Since the weight can be reduced while maintaining the rigidity, and the joint portion of the gasket can be used for positioning, it is possible to improve the assembling property.

In the invention described in claim 4, the cylinder head is provided with a cooling water passage and an intake port, the opening is connected to the intake port, and the head mounting flange is attached to the cylinder head. And, in an intake manifold of an engine provided with a plurality of branch pipes connected to the head mounting flange,
The head mounting flange is formed of a synthetic resin, and the head mounting flange includes a closing portion corresponding to an opening communicating with the cooling water passage, and the closing portion has an opening communicating with the cooling water passage. It is attached to the cylinder head via a gasket having a contact surface.

The closing portion of the head mounting flange corresponding to the opening communicating with the cooling water passage is attached to the cylinder head via a gasket having a surface that abuts on the opening communicating with the cooling water passage. It is possible to improve the rigidity of the seal portion surrounding the portion and to prevent the cooling water from directly contacting the synthetic resin head mounting flange, so that even a material having no water resistance can be used. It can be selected as a material for the head mounting flange, and it is possible to use common parts and reduce costs.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS First, an outline of an automobile engine 1 using an intake manifold according to an embodiment of the present invention will be described with reference to FIGS. FIG. 10 shows a front view of the engine, and FIG. 11 shows a plan view thereof. The engine 1 has a crankcase 2 positioned substantially at the center, a cylinder block 4 mounted on an upper portion of the crankcase 2, and an oil pan 5 mounted on a lower portion. A cylinder head 6 is provided above the cylinder block 4.
A surge tank 7 is arranged above the cylinder head 6. The crankshaft 3 protrudes from the crankcase 2.

An upper end of a branch 8a of the intake manifold 8 is connected to the surge tank 7, and a lower end thereof is connected to one side of the cylinder head 6. A PCV pipe 10 is connected between the surge tank 7 and the cylinder head cover 9 attached to the upper part of the cylinder head 6. Reference numeral 11 denotes an exhaust manifold, and reference numeral 12 denotes an exhaust sensor.

Hereinafter, an intake manifold according to an embodiment of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a perspective view showing the surge tank 7, the intake manifold 8, and the head mounting flange 13 manufactured by integral molding of synthetic resin, FIG. 2 is a front view of the same, and FIG. 3 is a plan view thereof. This engine has three cylinders, and the head mounting flange 13 is provided with three openings 13e, 13f, and 13g connected to the intake port. The head mounting flange 13 is connected to the surge tank 7 via branches 8a, 8b and 8c.
The surge tank 7 is disposed above the surge tank 3.
And the throttle body are positioned at substantially the same height as the cylinder head cover 9. The intake manifold is molded as a resin using a low-temperature molten metal core in the same manner as aluminum casting, and then integrally molded using a material called PA6-GF30, which is a kind of nylon, by a method called a lost core that melts only the core. .

When the surge tank 7 is positioned above the head mounting flange 13 as described above, since the load of the surge tank 7 and the throttle body is received by the intake manifold 8, a member connecting the surge tank 7 and the head mounting flange 13 is provided. Are the branches 8a and 8b of the intake manifold 8.
And 8c only, to increase the support rigidity,
Between the surge tank 7 and the head mounting flange 13, two pairs 4 in a direction intersecting the longitudinal direction of the head mounting flange 13.
A single plate-shaped rib 23 and a single rib 24 extending in the longitudinal direction of the head mounting flange 13 are provided to reinforce the entire intake manifold. The rib 24 is provided with a tool hole 24a for inserting a tool, and the rib 24 located between the pair of ribs 23 has three holes for lightening positioned on the side of the tool hole 24a. Provided. The tool hole 24a is formed between the pair of ribs 23 located on the left and right and between the pair of ribs 23 so as to be located on the side of the curved portion of the branch 8a. 2 and 3 is a nipple for connecting the PCV pipe 10.
Reference numeral 16 in FIGS. 1 and 2 denotes a negative pressure extracting pipe for connecting a vacuum hose.

As shown in FIG. 1, the surge tank 7 has a trapezoidal substantially rectangular parallelepiped shape having a wide upper surface, and its longitudinal direction is the longitudinal direction of the head mounting flange 13 (the longitudinal direction of the engine not shown). It is facing the same direction. By providing a concave portion on the upper surface of the surge tank 7 formed wider than the lower surface, the volume of the surge tank 7 is adjusted, and the side surface of the surge tank 7, that is, one end in the longitudinal direction of the engine is apparent from FIG. As described above, the lower end portion is formed on the inclined surface 7a facing downward with the lower end portion located on the other end side of the upper end portion. The upper ends of the branches 8a, 8b and 8c of the intake manifold 8 are connected to the inclined surface 7a. The lower end of each branch 8a, 8b and 8c has three openings 13e, 13f of the head mounting flange 13.
And 13g. Reference numeral 7b in FIGS. 1 and 2 is a mounting flange for mounting a throttle body (not shown), and reference numeral 7c is an opening through which an air-fuel mixture flows.

As shown in FIGS. 2 and 3, the head mounting flange 13 has three openings 13e, 13f, and 13g communicating with the intake ports formed in the cylinder head 6.
And the openings 13e, 13f and 13 as shown in FIG.
and a delivery head for fixing the delivery pipe 17 via a stay 26 and a cylinder head mounting boss 28 formed at the top and bottom of the g to surround the four corners of each of the openings 13e, 13f and 13g. A pipe fixing boss 27 (corresponding to each of the stay 18 and the boss 19 in FIG. 12) is provided. The delivery pipe fixing boss 27 is disposed at a position substantially at the center between adjacent cylinders and between the plurality of cylinder head mounting bosses 28 provided on the head mounting flange 13. You. Each opening 13e, 13f and 1
3g has a communicating portion formed in a long hole in the longitudinal direction of the head mounting flange 13 and a projecting portion formed by projecting a central portion of the communicating portion upward. An injection unit is provided.

As shown in FIG. 4 showing a cross section taken along line AA of FIG. 2, the center axis G of the delivery pipe fixing boss 27 (the center axis of the mounting bolt 29) is aligned with the cylinder axis (the cylinder head 6).
And the center axis of the cylinder head cover 9), and is inclined toward the delivery pipe 17 side so as to be separated from the engine.
The delivery pipe 17 can be easily attached and detached even in the state in which is attached. With this configuration,
This is particularly effective for a DOHC type engine in which the upper portion of the cylinder head 6 projects outward.

FIG. 5 is an enlarged view of a main part of FIG.
3 shows a positional relationship between the injector 15 and a delivery pipe fixing boss 27 that supports the delivery pipe 17. As shown in the figure, the hole center K of the injector 15 and the center L of the delivery pipe fixing boss 27 are arranged close to each other.

As described above, the delivery pipe fixing boss 27 that supports the delivery pipe 17 is disposed so as to be sandwiched between the adjacent cylinder head mounting bosses 28 and is integrated with the highly rigid head mounting flange 13. Providing this is extremely advantageous in terms of vibration resistance. As described with reference to FIG. 5, since the mounting portion of the delivery pipe 17 and the mounting portion of the injector 15 are arranged close to each other, the dimensional tolerance of the intake manifold 8 decreases,
Mounting accuracy can be improved. This is effective in preventing dimensional change due to warpage of the synthetic resin intake manifold, which has lower dimensional accuracy than casting, brazing, and dimensional change in a welded joint.

Next, the gasket mounting portion will be described. FIG. 6 shows a gasket 30 according to the present invention. The gasket 30 is of a so-called O-ring type, and has a flange surface 2 of the cylinder head 6.
1 (see FIG. 13), and has a seal portion 30a surrounding the periphery of the opening 21a. In addition, flange surface 2
The sealing portion 30a surrounding the three opening portions 21a is connected by a connecting portion 30b to facilitate the mounting work of the gasket 30. The gasket 30 is provided with a seal portion 30c surrounding the hole 21c integrally with the gasket 30 at a position corresponding to the hole 21c for cooling water of the cylinder head. Further, a film-like surface portion 30d is provided inside the seal portion 30c so as to close a hole 21c (see FIG. 13) for cooling water of the cylinder head. The gasket 30 has a sealing portion 30 surrounding the opening 21a of the flange surface 21 in which a sealing portion 30c for closing the hole 21c for cooling water is integrally provided.
A detachable knob is formed at the upper part of a (the part that comes into contact with the protrusion of the opening of the head mounting flange).

FIG. 7 shows the gasket 30 shown in FIG. 6 mounted on the head mounting flange 13 of the intake manifold 8. The head mounting flange 13 has three openings 13e and 13f corresponding to each cylinder.
And 13g, a plurality of lightening portions 13a, and a connecting rib 13b for connecting these lightening portions 13a, and the connecting rib 13b is a sectional view taken along the line BB in FIG. As shown in FIG. 7, a groove 13h extending in the longitudinal direction is formed. The connecting portion 30b of the gasket 30 is fitted in the groove 13h.

With such a configuration, the connecting portion 30b of the gasket 30 is
Are held by the groove 13h of the connecting rib 13b, and
A seal portion 30c surrounding the cooling water hole 21c and a film-like surface portion 30d formed inside the seal portion 30c are formed in the gasket 30 so that the cooling water hole 21c of the cylinder head is formed.
c (see FIG. 13), the cooling water is cut off by the film-like surface portion 30d of the gasket 30, as shown by the bold arrow in FIG. Therefore, the closing portion 1 of the head mounting flange 13
There is no direct contact with 3d.

[0034]

Since the present invention is an intake manifold for an engine constructed as described above, according to the first aspect of the present invention, a delivery is provided between a cylinder head mounting boss formed on a head mounting flange. Since the pipe fixing boss is formed, the rigidity of the delivery pipe fixing boss can be improved, and the vibration of the engine received by the injector and the delivery pipe can be reduced.

According to the second aspect of the present invention, in addition to the above-described effects, the delivery pipe fixing boss can be arranged at a distance from the side surface of the engine, so that the intake manifold is attached to the cylinder head. Even
The delivery pipe can be easily attached and detached. Further, even in the case of a DOHC engine in which the upper portion of the cylinder head projects outward, the boss for fixing the delivery pipe can be formed so as to avoid the overhang.

According to the third aspect of the present invention, the rigidity of the head mounting flange can be maintained and the weight can be reduced, and the gasket connecting portion is formed in the groove formed in the connecting rib of the head mounting flange. By fitting, the joint portion of the gasket can be used for positioning, so that the assemblability can be improved.

Further, according to the fourth aspect of the invention, it is possible to improve the rigidity of the sealing portion surrounding the cooling water opening, and to allow the cooling water to flow directly to the head mounting flange made of synthetic resin. Therefore, even if the material does not have water resistance, it can be selected as a material for the head mounting flange, and it is possible to use common parts and reduce costs.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an entire intake manifold according to an embodiment of the present invention.

FIG. 2 is a front view of the intake manifold of FIG.

FIG. 3 is a plan view of the intake manifold of FIG. 2;

FIG. 4 is a sectional view taken along line AA of FIG. 2;

FIG. 5 is an enlarged sectional view showing a main part of FIG. 4;

FIG. 6 is a front view of the gasket according to the present invention.

FIG. 7 is a front view showing a state where the gasket of FIG. 6 is mounted on a head mounting flange of an intake manifold.

FIG. 8 is a sectional view taken along line BB of FIG. 7;

FIG. 9 is an enlarged sectional view taken along line CC of FIG. 7;

FIG. 10 is a front view of an engine to which the present invention is applied.

11 is a plan view of the engine shown in FIG.

FIG. 12 is a side view showing a conventional injector and delivery pipe fixing structure in a partial cross section.

FIG. 13 is a front view showing only a flange surface of the cylinder head.

FIG. 14 is a front view showing a state where a conventional gasket is mounted on a flange surface of the cylinder head of FIG.

FIG. 15 is a front view showing a state where the same gasket as that of FIG. 14 is mounted on a head mounting flange of an intake manifold.

FIG. 16 is a sectional view taken along line DD of FIG. 15;

FIG. 17 is a front view showing a state where a gasket without a connection portion is mounted on a head mounting flange of an intake manifold different from that of FIG. 15;

FIG. 18 is a sectional view taken along line EE in FIG. 17;

FIG. 19 is an enlarged sectional view taken along line FF of FIG. 17;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Engine 6 Cylinder head 8 Intake manifold 8a, 8b, 8c Branch 13 Head mounting flange 13a Lightening portion 13b Connecting rib 13d Closing portion 13e, 13f, 13g Branch opening 13h Groove 27 Delivery pipe fixing boss 28 Cylinder head mounting boss 30 Gasket 30a, 30c Seal part 30b Joint part 30d Surface part

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F02M 55/02 350 F02M 35/10 102S 102B

Claims (4)

[Claims] 1. A head mounting flange provided with a plurality of openings connected to a plurality of intake ports provided in a cylinder head, the head mounting flange being mounted on the cylinder head,
In an intake manifold of an engine provided with a plurality of branch pipes connected to the head mounting flange, the head mounting flange has a delivery pipe fixing boss and a plurality of cylinder head mounting bosses between the adjacent openings. An intake manifold for an engine, wherein the delivery pipe fixing boss is formed between the plurality of cylinder head mounting bosses and disposed between the plurality of openings. 2. The boss for fixing the delivery pipe, wherein a longitudinal direction thereof is formed so as to be inclined with respect to an axis of a cylinder provided on a cylinder head so as to be separated from an engine. Engine intake manifold. 3. An engine having an opening connected to an intake port provided in a cylinder head, a head mounting flange mounted on the cylinder head, and a plurality of branch pipes connected to the head mounting flange. In the intake manifold, the head mounting flange includes a connecting rib between the adjacent openings and a lightening portion around the connecting rib, and a groove is formed in the connecting rib. An intake manifold for an engine, wherein a joint portion of a gasket in which a seal portion is connected by a joint portion is fitted. 4. A cylinder head having a cooling water passage and an intake port, an opening connected to the intake port, a head mounting flange mounted on the cylinder head, and a head mounting flange connected to the head mounting flange. In an intake manifold of an engine provided with a plurality of branch pipes, the head mounting flange is formed of a synthetic resin, and the head mounting flange includes a closing portion corresponding to an opening communicating with the cooling water passage, The intake manifold for an engine, wherein the closing portion is attached to a cylinder head via a gasket having a surface portion that contacts an opening communicating with a cooling water passage.