JPH11107870A - Intake manifold - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an intake manifold to be manufactured in a reduced weight and at a reduced cost and reduce the generation of radiation noises. SOLUTION: An intake manifold comprises a surge tank part 2 made of synthetic resin; a plurality of a branch pipes 3a-3d made of synthetic resin; and a joining flange 4 with which a cylinder head is joined. The branch pipes 3a-3d are surround as the branch pipes are widely curved in a direction, in which the pipe is separated away from an engine body, from the lower end of a surge tank part 2, and bent at the upper end thereof in a manner to extend toward an engine body. The ends on one side of the branch pipes 3a-3d are joined in a fitted-in state with connection ports 6a-6d, respectively, and the ends on the other side thereof are joined in a fitted-in state with the connection ports 8a-8d of joining flange 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an intake manifold, and more particularly to an intake manifold using a synthetic resin pipe.

[0002]

2. Description of the Related Art A conventional intake manifold generally comprises an aluminum alloy casting having a plurality of substantially L-shaped branch pipes extending downward from a surge tank portion. There was a problem that was high.

Therefore, as shown in FIG. 4, for example, a plurality of branch pipes 21a to 21c obtained by bending an iron pipe are used, one end of which is joined to a joining flange 22, and the other end of which is joined to a surge tank part. Provisions have been made.

[0004] Further, in order to further reduce the weight and cost, there is also known a product formed of a synthetic resin molded product.
However, the shape is complicated in order to secure a sufficient length of the branch pipe in order to improve the medium-to-low speed torque, so that one or two resin molded products cannot be joined and configured. Are formed by joining a number of resin molded products.

[0005]

However, in the case of using the branch pipes 21a to 21c made of an iron pipe, the iron pipe is bent and brazed to other components such as the joint flange 22 and the joint 23. In addition, there is a problem that the cost is increased because further painting is required. In addition, when an iron pipe is used, there is a problem that high-frequency radiation noise is increased.

In the case of a synthetic resin molded product, a large number of molded products need to be joined by welding or the like as described above, and a large number of molding dies are required, and the number of joining steps is large. Therefore, there is a problem that it becomes expensive.

[0007] In view of the above-mentioned conventional problems, an object of the present invention is to provide an intake manifold which can be manufactured lightly and inexpensively and can reduce radiated sound.

[0008]

According to the present invention, a surge tank made of a synthetic resin, a plurality of branch pipes made of a synthetic resin extending from the surge tank, and tips of the plurality of branch pipes are connected. And a joining flange made of metal or resin that is joined to the cylinder head of the engine.The branch pipe extends the surge tank section while largely bending the synthetic resin pipe away from the engine body from the lower end of the surge tank section. Surrounded and bent at the upper part so as to extend toward the engine body, one end of this branch pipe is fitted and joined to the connection port of the surge tank, and the other end is fitted and joined to the connection port of the joining flange. It is.

According to such a configuration, the surge tank and the branch pipe are made of synthetic resin, so that the weight can be reduced. Further, since the surge tank can be formed in a simple shape, a small number of dies can be formed by resin molding. In addition to being able to be manufactured at low cost, branch pipes are made by bending inexpensive synthetic resin pipes even if long pipes are used to improve medium-to-low-speed torque. The length can be freely selected because the fitting flange is press-fitted or connected with a connector, etc.
In addition, it can be manufactured at low cost, and since the surge tank and the branch pipe are made of synthetic resin pipes, radiated sound can be reduced. Can be configured.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of an intake manifold according to the present invention will be described below with reference to FIGS.

In FIG. 1, an intake manifold 1
Is a joint for joining to the surge tank portion 2, a plurality of branch pipes 3a to 3d (four in the illustrated example, since the engine body (not shown) is four cylinders), and a cylinder head side surface of the engine body. It is composed of a flange 4.

The surge tank portion 2 is formed of a synthetic resin molded product, and has a substantially rectangular parallelepiped shape in a longitudinal direction along the cylinder arrangement direction of the engine body, and upper portions on both sides thereof are inclined so as to follow the flow of intake air. With the engine body side (back side)
The upper portion is formed to be inclined so as to secure a space for disposing the joining flange 4 and to follow the flow of intake air. At the center of the upper surface of the surge tank 2 on the near side far from the engine body, an inlet 5 is formed so as to be fitted and connected to an outlet of a throttle body (not shown). In addition, connection ports 6a to 6d of the branch pipes 3a to 3d are provided on the lower surface. These connection ports 6a to 6d are connected to the connection port 6 at the center.
b, 6c are arranged on the back side, and the connection ports 6a, 6d on both sides are arranged on the near side, so that they are located at substantially equal distances around the entrance portion 5 and the lengths of the branch pipes 3a to 3d are the same. Is configured.

Each of the branch pipes 3a to 3d is composed of a synthetic resin pipe manufactured by extruding a synthetic resin such as nylon, and as shown in FIG.
Surrounding the surge tank portion 2 while largely curving to the front side from the connection ports 6a to 6d at the lower ends of the surge tank portion 2, the upper portion is formed in a predetermined shape extending toward the engine body.

The joining flange 4 is made of a deep drawn product of an iron plate, and a joining bolt hole 7 for joining to one side of a cylinder head (not shown) of the engine body is appropriately arranged. The connection ports 8a to 8c of the branch pipes 3a to 3d are provided at positions opposed to the intake ports of the cylinder head.
8d is protruded.

The branch pipes 3a to 3d are shown in FIG.
As shown in (a), a bellows portion 9 is formed at the bent portion as necessary so that the bending can be performed appropriately and easily. A connector 10 is attached to one end of each of the branch pipes 3a to 3d so that the connection ports 6a to
The other end of each of the branch pipes 3a to 3d is press-fitted into the connection ports 8a to 8d of the joining flange 4 and is fitted and joined. In addition,
FIG. 2A illustrates an example in which one bead for sealing is formed in the connection ports 8a to 8d of the joining flange 4.
It goes without saying that two or more beads may be formed as shown in FIG.

Next, the connector 10 and the connection port 6 (6a-6)
To explain the connection configuration of d), as shown in FIGS. 2 and 3, one half of the connector 10 is fitted into the inner periphery of the connection port 6,
A connection cylinder portion 11 into which the branch pipes 3a to 3d are press-fitted on the outer periphery of the other half portion, and an elastically deformable engagement ring 12 disposed so as to fit on the outer periphery of the connection port 6; The engagement ring 12 is connected to the center of the connection tube 11 by a pair of connection pieces 12a. An engagement protrusion 13 having a triangular cross section is provided on the outer periphery of the connection port 6 and the engagement ring 1 is provided.
A pair of engaging projections 14 that can engage with the engaging projections 13 are provided at two diametrical locations on the inner circumference of the second 2, and the engagement ring 12 is in a natural state as shown in FIG. The diametrical direction in which the locking projections 14 are arranged has an elliptical shape with a minor axis, and the major axis direction is pressed as shown by an arrow A, so that the arrangement portion of the locking projections 14 is an arrow B as shown in FIG. Thus, the engagement between the locking projection 14 and the engaging projection 13 is released by displacing outward in the radial direction, and the connector 10 can be detached. Reference numeral 15 denotes an O-ring mounted on the outer periphery of one half of the connection cylinder 11, which is compressed while being fitted to the connection port 6 and seals both.

In the above configuration, when the intake manifold 1 is assembled, the joining flange 4 is joined and fixed to one side of the cylinder head of the engine body, and then the surge tank is attached to the outlet of the throttle body fixed and supported by the engine body. The branch pipes 3a to 3a fitted with the inlet portion 7 of the portion 2 and extended from the joint flange 4
The assembling is completed only by inserting and fitting the connector 10 at the distal end of d into the connection ports 6a to 6d protruding from the lower surface of the surge tank portion 2, respectively.

Further, the intake air flowing from the throttle body into the surge tank portion 2 uniformly flows to the respective connection ports 6a to 6d, and flows toward the intake port of the cylinder head through the long curved long branch pipes 3a to 3d. So
High intake efficiency can be obtained by inertial intake, and medium-low speed torque can be improved. Further, since the surge tank 2 and the branch pipes 3a to 3d are made of synthetic resin, radiated sound can be reduced.

Further, since the surge tank 2 and the branch pipes 3a and 3b are made of synthetic resin, and the joining flange 4 is also made of a deep drawn product of an iron plate, the weight can be reduced. Further, since the surge tank portion 2 has a simple substantially rectangular parallelepiped shape, it can be manufactured at low cost by resin molding using a two-piece mold, and the branch pipes 3a to 3d are formed by using inexpensive extruded pipes. It is inexpensive because it is formed by bending, and both ends of these pipes are connected to the connection ports 6a to 6d and 8 of the surge tank portion 2 and the joining flange 4 respectively.
It can be manufactured inexpensively because it is press-fitted to a to 8d and fitted and joined by the connector 10 or the like.

Further, the branch pipes 3a to 3d are curved so as to surround the surge tank portion 2, and the surge tank portion 2, the branch pipes 3a to 3d
, The intake passage leading to the joining flange 4 is formed into an α-shape in a side view, so that the branch pipes 3a to 3d
The intake device can be made compact while ensuring a long length and without sharp bends.

In the above embodiment, the branch pipe 3
Connection ports 6a to 6d of surge tank 2 at one end of a to 3d
The connector 10 is used for connection with the connection flange 8 and the connection ports 8a to 8d of the joint flange 4 are connected by press-fitting. However, the press-fit connection and the connector connection may be reversed or both may be press-fitted or connector-connected. Needless to say. Also, the connector 10 is not limited to the quick connector shown in the figure, and any connector can be used.

[0022]

According to the intake manifold of the present invention, since the surge tank and the branch pipe are made of synthetic resin as described above, the weight can be reduced, and the surge tank can have a simple shape. In addition to being able to be manufactured at low cost with a small mold by resin molding, the branch pipe is inexpensive because it is formed by bending an inexpensive synthetic resin pipe even if a long one is used to improve the middle and low speed torque,
In addition, since both ends of these pipes are fitted and connected to the connection port of the surge tank and the joint flange by means of press fitting and connectors, etc., it can be manufactured at low cost, and since the surge tank part and branch pipe are made of synthetic resin pipe, radiation noise And the branch pipe is curved so as to surround the surge tank even if the length of the branch pipe is long.

[Brief description of the drawings]

FIG. 1 shows an embodiment of an intake manifold according to the present invention, wherein (a) is a plan view, (b) is a front view, and (c) is a side view.

FIGS. 2A and 2B show a configuration of a joining flange of the branch pipe and a joining portion of the branch pipe of the embodiment with a surge tank portion, wherein FIG. 2A is a partial cross-sectional side view, and FIG. FIG.

FIGS. 3A and 3B show a connector for joining a branch pipe and a surge tank in the same embodiment, wherein FIG. 3A is a transverse sectional view showing a joined state, and FIG. 3B is a transverse sectional view showing a detached state.

FIG. 4 is a perspective view of a conventional iron pipe intake manifold.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Intake manifold 2 Surge tank part 3a-3d Branch pipe 4 Joint flange 6a-6d Connection port 8a-8d Connection port

Claims (1)

[Claims] 1. A surge tank made of synthetic resin, a plurality of branch pipes made of synthetic resin extending from the surge tank, and tips of the plurality of branch pipes are connected and joined to a cylinder head of the engine. The branch pipe is bent so that the synthetic resin pipe surrounds the surge tank portion and extends toward the engine body at an upper portion thereof while largely bending the synthetic resin pipe in a direction away from the engine body from the lower end of the surge tank portion. Configure
An intake manifold in which one end of the branch pipe is fitted and joined to a connection port of a surge tank, and the other end is fitted and joined to a connection port of a joining flange.