JPH068756U - Connection structure between intake manifold and cylinder head - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a connection structure between an intake manifold and a cylinder head that does not cause a step difference that causes ventilation resistance at a connection portion. [Configuration] Multiple branch pipes in the intake manifold (1)
Each tip (2a) of (2) is joined to the flange (3) for attachment to the cylinder head (6) in a penetrating manner so as to slightly project from this. On the other hand, in each cylinder head intake hole (7) of the same diameter as the branch pipe (2), from the inlet to the tip of the branch pipe (2).
An annular step portion (7a) having an L-shaped cross section is formed at a position inwardly extending by the protruding length of (2a). And each branch pipe
The tip (2a) of (2) is fitted into the inlet end of each air intake hole (7) and is received by the step (7a).

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a connection structure between an intake manifold and a cylinder head used in, for example, an automobile engine.

In this specification, aluminum means an aluminum alloy in addition to pure aluminum.

[0003]

[Prior art]

 Fig. 3 shows the conventional connection structure between the intake manifold and the cylinder head. The intake manifold (21) is composed of a plurality of branch pipes (22) and a flange for mounting to the engine cylinder head (26). (23) and are provided. The flange (23) has the same number of branch pipe connection holes (24) as the branch pipes (22), and the same holes (24) are provided from the opening on the side opposite to the cylinder head (26). An annular step portion (24a) having an L-shaped cross section is formed at a position inwardly of the length. Then, the tip end (22a) of each branch pipe (22) is fitted into the hole (24) of the flange (23) from the side opposite to the cylinder head (26) and received by the step (24a), and the brazing material Is brazed to the flange (23).

On the other hand, the cylinder head (26) has the same number of intake holes (27) as the branch pipes (22), and the diameter of each intake hole (27) is the same as that of the hole (24) of the flange (23). The diameter is the same as the diameter of the opening on the cylinder head (26) side. In the cylinder head (26) shown in FIG. 3, (8) is an exhaust hole, (9) is a combustion chamber, (10) is an intake valve, (11) is an exhaust valve, and (12) is an ignition plug. .

When connecting the intake manifold (21) and the cylinder head (26), the opening (24) of the hole (24) of the flange (23) on the cylinder head (26) side and the cylinder head (26) are connected. The side surface of the flange (23) on the cylinder head (26) side against the outer surface of the cylinder head (26) so that the inlet of the suction hole (27) of the ) Was attached and fixed to the cylinder head (26).

[0006]

[Problems to be solved by the device]

 However, when connecting the intake manifold (21) and the cylinder head (26) as described above, the opening of the hole (24) of the flange (23) on the cylinder head (26) side and the cylinder head (26). It was difficult to exactly match the inlet of the intake hole (27) of the, and the positions of both were often misaligned. Then, there is a problem in that the step created at the boundary between the two due to the deviation becomes an airflow resistance, which reduces the intake air flow rate, leading to deterioration in engine performance.

Further, conventionally, the diameter of the inlet of the intake hole (27) of the cylinder head (26) is made slightly larger than the diameter of the opening of the hole (24) of the flange (23) on the cylinder head (26) side. However, there were some that tried to cover the gap between the two at the time of connection, but in this case as well, the engine performance was reduced by cutting the inlet end of the intake hole (27) and increasing its diameter. There was a problem of giving down.

An object of the present invention is to solve the above problems and provide a connection structure between an intake manifold and a cylinder head that does not cause a step difference that is a cause of ventilation resistance in a connection portion.

[0009]

[Means for Solving the Problems]

 In order to achieve the above-mentioned object, the connection structure between the intake manifold and the cylinder head of the present invention is such that the tip ends of the plurality of branch pipes in the intake manifold project slightly from the flange for mounting on the cylinder head. Each cylinder head intake hole of the same diameter as the inner diameter of the branch pipe is connected to the cylinder head intake hole so that the cross section is located inward from the inlet by the protruding length of the tip of the branch pipe. An L-shaped and annular step portion is formed, and the tip end portion of each branch pipe is fitted into the inlet end portion of each intake hole and received by the step portion.

In the above description, it is preferable that the tip ends of the plurality of branch pipes in the intake manifold are projected by 2 mm to 20 mm from the flange for attachment to the cylinder head.

[0011]

[Action]

 According to the connection structure of the intake manifold and the cylinder head of the present invention, the respective tip portions of the plurality of branch pipes in the intake manifold are joined to the flange for attachment to the cylinder head in a penetrating manner so as to slightly project therefrom. On the other hand, in each cylinder head intake hole of the same diameter as the inner diameter of the branch pipe, at the position that is inward from the inlet by the protruding length of the tip of the branch pipe, an annular step with an L-shaped cross section is formed. Is formed, and the tip of each branch pipe is fitted into the inlet end of each intake hole and received by the step, so that the inside of each branch pipe and each intake hole at the connecting part are vented to the boundary between them. It is made flush without causing a step that causes resistance.

[0012]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings.

As shown in FIG. 2, the intake manifold (1) includes four branch pipes (2) made of aluminum wrought material and a flange made of aluminum wrought material for mounting on an engine cylinder head (6). (3) and are provided. The flange (3) is in the shape of a horizontal rectangular plate, and four branch pipe connecting holes (4), which are the same number as the branch pipes (2), are formed in parallel in the upper and lower central portions. Also, a plurality of bolt insertion holes (5) are formed in the peripheral portion of the flange (3). The flange (3) may be a cast product.

Then, each tip portion (2a) of the branch pipe (2) is inserted into each hole (4) of the flange (3) so as to protrude from the flange (3) by 20 mm, so that the brazing material is used. By being attached, they are joined in a penetrating manner. In the above, the branch pipes (2) and the flanges (3) are joined by brazing, but means other than brazing, for example, bonding using a thermosetting resin may be used. The tip (2a) of each branch pipe (2) is sized so that it fits snugly into the step (7a) formed at the inlet end of the intake hole (7) described below. Be shaped.

Although not shown, each end of the branch pipe (2) is connected to the plenum chamber. The plenum chamber is made of aluminum wrought material with one end open and the other end closed. A throttle body mounting tubular member made of cast aluminum is fixed to the open end of the plenum chamber. A throttle body mounting flange is integrally provided at one end of the throttle body, and a throttle body with a built-in throttle valve is mounted on the throttle body mounting tubular member. Connected.

FIG. 1 shows a state in which the intake manifold (1) having the above-mentioned configuration is connected to the cylinder head (6). Each cylinder head intake hole (7) has a branch pipe (2). It has the same diameter as the inner diameter, and it is 20 mm inward from the inlet by the protruding length of the tip (2a) of the branch pipe (2). 7a) has been formed. The step portion (7a) is formed by machining the inlet end portion of each intake hole (7).

When connecting the intake manifold (1) and the cylinder head (6), first connect the tip end (2a) of each branch pipe (2) to the inlet end of each intake hole (7). As it is fitted in, the tip portion (2a) is received by the step portion (7a). Next, the flange (3) is attached and fixed to the cylinder head (6) with a plurality of bolts (not shown). In the above description, the inside of each branch pipe (2) and each intake hole (7) in the connecting portion are made flush with each other without any step difference which causes a ventilation resistance at the boundary between them.

[0018]

[Effect of device]

 According to the connection structure of the intake manifold and the cylinder head of the present invention, the insides of the respective branch pipes and the respective intake holes at the connecting portion are flush with each other without causing a step which causes a ventilation resistance at the boundary between them. As a result, it is possible to reduce the ventilation resistance at the connecting portion compared to the conventional one, and it is possible to improve the engine performance by increasing the intake flow rate.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing a connection state between an intake manifold and a cylinder head in an embodiment of the present invention.

FIG. 2 is a perspective view of a main part with a part of an intake manifold of the embodiment omitted.

FIG. 3 is a vertical cross-sectional view showing a connection state between a conventional intake manifold and a cylinder head.

[Explanation of symbols]

 (1) …… Intake manifold (2) …… Branch pipe (2a) …… Tip (3) …… Cylinder head mounting flange (6) …… Cylinder head (7) …… Cylinder head intake hole ( 7a) ... Step section

Claims (1)

[Scope of utility model registration request] 1. A plurality of branch pipes in an intake manifold (1).
Each tip (2a) of (2) is connected to the flange (3) for mounting to the cylinder head (6) in a penetrating manner so as to project slightly from this, while it is the same as the inner diameter of the branch pipe (2). Each cylinder head intake hole (7) of diameter has a cross section L at a position that is inward from the inlet by the protruding length of the tip end (2a) of the branch pipe (2).
-Shaped and annular step (7a) is formed, and the tip (2a) of each branch pipe (2) is fitted into the inlet end of each intake hole (7)
Connection structure between intake manifold and cylinder head received in (7a).