JPH08200063A - Intake manifold - Google Patents

Abstract

PURPOSE: To easily remove bubbles in cooling water by arranging a passage up to reaching a flood part in a flange so as to be opened on its installing surface. CONSTITUTION: An intake manifold is provided with a branch pipe 2 to introduce sucking air up to an intake air port 3 and a branch pipe installing flange 4 arranged in an intake air port side end part of the branch pipe 2. A groove 8 which is communicated with a water jacket 6 arranged in a cylinder head 5 and is communicated with a flood part of cooling water, is arranged so as to be opened on an installing surface brought into close contact with the cylinder head 5 of the flange 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intake manifold mounted on a vehicle engine such as a water-cooled slant engine mounted on a vehicle with a cylinder tilted.

[0002]

2. Description of the Related Art Conventionally, in this type of intake manifold, a cooling water passage called a cooling water outlet pipe communicating with a water jacket is integrally formed in order to remove bubbles mixed in the cooling water when pouring water into the cylinder head. It is known to be provided (for example, in Japanese Utility Model Laid-Open No. 61-197217).
issue). The intake manifold having such a cooling water passage is generally formed by casting aluminum, for example. Further, when the intake manifold as described above is applied to a slant engine, normally, as shown in FIG. 5, the cooling water passage a is arranged on the lower surface portion of each branch pipe b in order to improve the escape of bubbles. Often becomes.
In FIG. 5, c is a cylinder head, d is a water jacket, and e is an intake port.

[0003]

By the way, when the intake manifold is formed of aluminum, it can be formed by using the core for the cooling water passage. If it is located on the lower surface of the port, since the intake air is warmed by the heat of the cooling water when it is made of aluminum, which has a high heat transfer efficiency, the volume efficiency of the intake air becomes small. This adversely affects the performance of the engine, because it causes the air-fuel ratio to fluctuate.

Due to such a problem, an intake manifold made of a synthetic resin having a small thermal conductivity is conceivable. However, in the case of a synthetic resin, it is difficult to use a core in a mold, so the intake manifold is called. It becomes necessary to integrate the cooling water passages, which are molded separately, by welding.
In this case, since it is a separate body, the productivity is lowered, and as a result, the manufacturing cost may be increased.

[0005] An object of the present invention is to solve such a problem.

[0006]

In order to achieve the above object, the present invention takes the following measures. That is, the intake manifold according to the present invention,
A branch pipe that guides intake air to the intake port and a branch pipe mounting flange that is provided at the end of the branch pipe on the intake port side are connected to a water jacket provided in the cylinder head, and cooling water is provided. The groove communicating with the water discharge part is opened in the mounting surface of the flange that is in close contact with the cylinder head.

[0007]

With this structure, since the passage for the cooling water to reach the water outlet is provided in the flange so as to open on the mounting surface, the branch pipe through which the intake air flows is heated. There is no. That is, since the cooling water flows in the flange, the branch pipe is not directly heated, and since the heat conduction from the flange is small, the branch pipe is indirectly heated as much as possible. For this reason, it is possible to efficiently remove the air bubbles at the time of water injection, and it is not necessary to reduce the volumetric efficiency of the intake air when the engine is operating.
There is no change in the air-fuel ratio.

Further, since the groove is opened on the mounting surface of the flange, it is easy to make it by casting or the like. Therefore, for example, even in the case of integrally molding with synthetic resin, the groove can be formed without using the core, so that the manufacturing becomes easy.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

An intake manifold 1 shown in the drawings is made of a synthetic resin, and is mounted on a slant engine for an automobile of in-line 4-cylinder and has four branch pipes 2.
That is, the intake manifold 1 includes a branch pipe 2 that guides intake air to the intake port 3 and an intake port 3 of the branch pipe 2.
And a flange 4 for attaching a branch pipe provided at the end portion on the side of the cylinder head 5, which communicates with a water jacket 6 provided in the cylinder head 5 and also with a cooling water outlet chamber 7 serving as a cooling water outlet. The groove 8 with the flange 4
The mounting surface 4a that is in close contact with the cylinder head 5 is opened. The intake manifold 1 is formed by welding two separately molded products in the direction of arrow A shown in FIG.

Each branch pipe 2 is formed so that an intake air flow path is branched from the surge tank T (shown in FIG. 2) in accordance with the interval between the intake ports 3 of the cylinder head 5. The ends of the branch pipes 2 on the opposite side to the surge tank T are connected in a direction substantially perpendicular to the opening direction of the branch pipes 2 by flanges 4 for fixing the respective branch pipes 2 to the intake ports 3 in a communicating manner. There is. The sectional shape of the branch pipe 2 is substantially circular at the end on the side of the surge tank T, is oval at the end on the side of the flange 4, and is smooth from a substantially perfect circle to an elliptical shape at the intermediate portion. It has been transformed into. In this embodiment, each of the branch pipes 2 has a lower molded product 2a located on the lower side and an upper molded product 2b located on the upper side when being attached to a slant engine. A tube shape is formed by closely adhering 2c and welding. The flange 4 is integrally formed at the end of the lower molded product 2a on the side opposite to the surge tank.

The thickness of a portion of the flange 4 located below the branch pipe 2 when mounted on the slant engine is
It is formed thicker than that of the part located above.
That is, as shown in FIG. 4, the thickness of the lower portion 4b is
The groove 8 is formed to have a thickness of about 1.5 times that of the upper portion 4c.
Has a sufficient cross-sectional area. The mounting surface 4a of the flange 4 is provided with a rib 4d for reinforcement. The groove 8 is provided in the lower portion 4b of the flange 4, and is open to the mounting surface 4a. As shown in FIG.
The cross-sectional shape is substantially rectangular. The groove 8 extends from one end of the flange 4 to the through hole 7a that communicates with the cooling water outlet chamber 7, and the other end of the flange 4 communicates with the intake port 3 of the first cylinder, for example. 2 extends from the vicinity of the opening position along the opening of each branch pipe 2. Upper part 4 of flange 4
A through hole 9 for attaching the fuel injection valve is formed in c at a position corresponding to the intake port 3. In FIGS. 1 and 3, reference numeral 10 is a bolt hole for mounting the intake manifold 1.

In this structure, the groove 8 is opened in the mounting surface 4a of the flange 4 during manufacturing, so that the mold can be easily manufactured. That is, a synthetic resin is used as a material, and a water channel for guiding cooling water to the cooling water outlet chamber 7 can be formed without using a core. Moreover, since it can be manufactured using a mold, mass production effect can be easily obtained, and as a result, manufacturing cost can be reduced.

When installed in a slant engine, the groove 8 communicates with the water jacket 6 of the cylinder head 5 at the end opposite to the cooling water outlet chamber 7. Usually, the slant engine is mounted so that the cylinders are positioned in line with the front-rear direction of the vehicle. The slant engine is fixed so that the front portion thereof is slightly higher than the rear portion, and the intake port 3 is on the upper side. The cylinder is inclined upward from the horizontal axis of the vehicle by a predetermined angle when viewed from the front. In such a mounted state, since the cooling water outlet chamber 7 is located on the front side of the slant engine, the groove 8 is inclined upward toward the cooling water outlet chamber 7. Therefore, when cooling water is injected into the water jacket 6, the bubbles mixed in the cooling water flow into the groove 8 from the other end of the groove 8 and reach the cooling water outlet chamber 7 along the inclination of the groove 8. It reaches and is released to the outside.

On the other hand, when the engine is operated, the heated cooling water flows through the groove 8 toward the cooling water outlet chamber 7. At this time, since the groove 8 is in the flange 4, the heat of the cooling water heats the branch pipe 2 through which the intake air flows is very small. That is, since the position of the groove 8 is apart from the branch pipe 2, the intake air is hardly heated. Moreover, since the branch pipe 2 and the flange 4 are both made of synthetic resin, the thermal conductivity is low, and the temperature of the cooling water is less likely to be transmitted to the intake air. Therefore, the volumetric efficiency of the intake air is not reduced, and it is possible to effectively prevent deterioration of engine performance.

The present invention is not limited to the embodiment described above.

In addition, the configuration of each section is not limited to the illustrated example, and various modifications can be made without departing from the spirit of the present invention.

[0018]

As described above in detail, according to the present invention, since the passage through which the cooling water reaches the water outlet is provided in the flange by opening it on the mounting surface thereof, the branch pipe through which the intake air flows can be provided. It is possible to prevent heating. That is, since the cooling water flows in the flange, the branch pipe is not directly heated, and since the heat conduction from the flange is small, it is possible to minimize heating indirectly. it can. For this reason, it is possible to efficiently remove bubbles during water injection, and it is possible to prevent the volumetric efficiency of intake air from decreasing during engine operation, and to prevent fluctuations in the air-fuel ratio.

Further, since the groove is opened on the mounting surface of the flange, it is easy to make it by casting or the like. Therefore, even when it is integrally molded with synthetic resin, the core is used. Since the groove can be formed without any, manufacturing becomes easy.

[Brief description of drawings]

FIG. 1 is a partially omitted top view showing an embodiment of the present invention.

FIG. 2 is a side view of the embodiment.

FIG. 3 is a bottom view of the flange of the embodiment.

FIG. 4 is an enlarged cross-sectional view showing a structure of a main part when the same embodiment is mounted on a slant engine.

FIG. 5 is a view corresponding to FIG. 4 of a conventional example.

[Explanation of symbols]

 1 ... Intake manifold 2 ... Branch pipe 3 ... Intake port 4 ... Flange 4a ... Mounting surface 5 ... Cylinder head 6 ... Water jacket 7 ... Cooling water outlet chamber 8 ... Groove

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display area F02M 35/10 311 C

Claims (1)

[Claims] 1. A branch pipe for guiding intake air to an intake port, and a flange for mounting a branch pipe provided at an end of the branch pipe on the intake port side. The branch pipe communicates with a water jacket provided in a cylinder head. In addition, the intake manifold is characterized in that a groove communicating with the water outlet of the cooling water is provided in the mounting surface of the flange that is in close contact with the cylinder head.