JPH06341355A - Suction manifold - Google Patents

Abstract

PURPOSE:To provide a suction manifold which is structured so that a surge tank and 21 branch pipe are connected into a consolidated body, which presents less thermal strain at forging and in the connecting process, and with which a connection strength as substitute for brazing can be secured. CONSTITUTION:The end part 3a of a branch pipe 3 is inserted into a connection hole formed in a surge tank 2, and a thermo-hardening resin adhesive is interposed between the wall surface of the connection hole and the peripheral surface of the end part 3a so that the two are attached, and also the foremost area of the end part 3a is widened diametrically for generating mechanical bond of the surge tank 2 with the branch pipe 3, or otherwise the outside protrusion 3c formed on the way of the end part 3a is restrained by the head 11a of a bolt 11 in the condition that the protrusion is contacted with the peripheral edge of the connection hole.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intake manifold in which a surge tank made of cast aluminum and a plurality of branch pipes are integrally formed.

[0002]

2. Description of the Related Art An intake manifold for supplying air-fuel mixture or air from a carburetor to each cylinder of an engine includes an integrated surge tank. In such an intake manifold, a surge tank having an opening at one end and the other end closed, a flange connected to an intake hole portion of an engine through a gasket, and one end of the surge tank to the flange It is composed of a plurality of branch pipes whose ends are connected.

The surge tank, the flange and the branch pipe are made of aluminum alloy for easy processing and weight reduction, the surge tank and the flange are made by casting, and the branch pipe is made of an extruded pipe. To be done. The connection between a surge tank and a flange made of cast aluminum and a branch pipe made of a pipe extruded material has been conventionally performed by JP-A-63-26896.
As described in Japanese Laid-Open Patent Publication No. 6, the method is performed by brazing.

Specifically, for example, in the case of a surge tank and a branch pipe, the surge tank and the branch pipe are connected to each other in a state where the end portion of the branch pipe is inserted into a connecting hole formed on the outer periphery of the surge tank and the branch pipe is about 580. It is placed in a furnace of N ₂ atmosphere heated to ° C, and a brazing material is supplied to the joint surface of both for brazing. Therefore, in the conventional intake manifold, as the material of the surge tank, the ambient temperature 580 during brazing is used.
It is necessary to use an aluminum alloy having a high melting point of ° or higher.

[0005]

However, high-melting-point aluminum alloys have a high rate of thermal strain during casting, and since they are heated to near the melting point due to the ambient temperature during brazing, the thermal strain is high. May occur.
That is, in the casting of aluminum alloy, when adopting the die casting method, it is important that the melting point is low and the difference with the mold temperature is small in order to obtain good castability with less thermal distortion, Being restricted to high melting point aluminum alloys can cause thermal strains both during casting and during brazing. The thermal strain of such a surge tank is
In particular, it deforms the cavity shape of the surge tank and affects the effect of preventing intake interference.

In view of the above points, the present invention has an object to provide an intake manifold in which heat distortion is less likely to occur during casting and during the connection process and the connection strength not depending on brazing is ensured. .

[0007]

[Means for Solving the Problems]
In the intake manifold of the invention, the end portion of the branch pipe is inserted into at least one of the connection hole formed in the surge tank and the connection hole formed in the flange corresponding to each branch pipe, and The wall surface of the hole and the outer peripheral surface of the end portion are adhered by a thermosetting resin adhesive, and the tip end region of the end portion of the branch pipe protruding from the connection hole is enlarged in diameter from the connection hole to form the peripheral portion. Is locked to.

According to a second aspect of the present invention, an outward projection is formed in the middle of each branch pipe, and a connection hole formed in the surge tank or a connection hole formed in the flange corresponding to each branch pipe. At least one of the holes is inserted in a state where the outer projection is in contact with the peripheral portion of the connecting hole, and the wall surface of the connecting hole and the outer peripheral surface of the end portion are thermosetting resin adhesive materials. And a bolt for retaining the outer protrusion with the head is fastened to the peripheral edge of the connecting hole.

[0009]

According to the intake manifold of the present invention, the surge tank and the branch pipe or the flange and the branch pipe are bonded by the thermosetting resin adhesive material, and brazing is unnecessary. Therefore, the aluminum alloy used for the surge tank or flange should have a low melting point higher than the heating temperature required for the bonding process (thermosetting) of the thermosetting resin adhesive, but lower than the ambient temperature required for brazing. it can. Such a low-melting aluminum alloy has a low thermal strain during casting, and has a melting point much higher than the heating temperature required for the bonding process of the thermosetting resin adhesive, so that it does not heat even when the adhesive is thermoset. There is no risk of distortion.

Further, according to the intake manifold of the first aspect of the present invention, the connection is made with the thermosetting resin adhesive as described above, and the tip end region of the branch pipe is expanded with a diameter larger than the diameter of the connection hole for connection. By engaging with the peripheral portion of the use hole, the connection strength is achieved by adding the adhesive force of the thermosetting resin adhesive and the mechanical connecting force between the end tip region and the connection hole. Similarly, in the second aspect of the invention, the mechanical coupling is achieved by restraining the outer protrusion of the branch pipe by the head of the bolt fastened to the peripheral portion of the connection hole to the adhesive force of the thermosetting resin adhesive. Forced connection strength is achieved.

[0011]

Therefore, according to the present invention, by bonding the surge tank and the branch pipe or the flange and the branch pipe with the thermosetting resin adhesive, the thermosetting resin can be used as the material of the surge tank or the flange. It is possible to use an aluminum alloy having a low melting point, which has a melting point higher than the heating temperature of the adhesive material but has little thermal strain during casting, and it is possible to manufacture a good intake manifold that avoids thermal strain during casting and during the bonding process.

Further, the end of the branch pipe inserted into the connecting hole is expanded in diameter from the diameter of the connecting hole, or the outer projection formed on the branch pipe is locked with a bolt to prevent heat. Achieving a connection strength in which the mechanical bonding force is added to the adhesive force of the curable resin adhesive.

[0013]

The present invention will be described in detail below with reference to the embodiments shown in the drawings. As shown in FIG. 1, an intake manifold 1 according to a first embodiment of the present invention has a surge tank 2 made of an aluminum alloy casting having an opening 2a at one end and a closed other end.
A plurality of branch pipes 3 made of aluminum extruded material each having a predetermined curved shape, and the other ends of the branch pipes 3 are commonly connected to the surge tank 2. And a flange 4 which is made of the same aluminum alloy casting and is coupled to an intake hole portion of an engine (not shown).

The surge tank 2 and the branch pipe 3 are shown in FIG.
They are connected as shown in (A). A connection hole 5 into which one end 3a of the branch pipe 3 is inserted is formed on a side portion of the surge tank 2. The thermosetting resin adhesive 6 is evenly applied to one end 3a of the branch pipe 3 by, for example, a spatula or a micro dispenser, and the end 3a to which the thermosetting resin adhesive 6 is applied is a surge. It is inserted into the connection hole 5 of the tank 2. As a result, the thermosetting resin adhesive material 6 acts on the wall surface of the connection hole 5 and the outer peripheral surface of the one end portion 3 a of the branch pipe 3, and the surge tank 2 and the branch pipe 3
Are connected in an adhesive form.

In this case, the peripheral edge portion 2a of the connecting hole 5 projects outward from the surge tank 2 in a flange shape, and a recess 7 having a diameter larger than that of the connecting hole 5 is formed in the surge tank 2 opposite thereto. ing. Then, as shown in FIG. 2 (B), the tip region of one end 3a of the branch pipe 3 protruding into the surge tank 2 is expanded by expansion processing, fitted in the recess 7, and connected. The locking form is adopted for 5.

On the other hand, the flange 4 and the branch pipe 3 are connected as shown in FIG. The flange 4 has the same number of connection holes 9 as the number of branch pipes 3. As shown in FIG. 3 (A), a flange-shaped outer projection 3c is formed in the middle of the other end 3b of the branch pipe 3 connected to the flange 4, and the tip end region is formed from the outer projection 3c. A thermosetting resin adhesive 8 is evenly applied to the same as the one end 3a connected to the surge tank 2. The other end 3b of the branch pipe 3 coated with the thermosetting resin adhesive 8
3C, the outer protrusion 3c is inserted into the connecting hole 9 in a state where the outer protrusion 3c is in contact with the peripheral edge of the connecting hole 9, whereby the thermosetting resin adhesive 8 is inserted into the connecting hole 9. It acts on the wall surface of 9 and the outer peripheral surface of the other end 3 b of the branch pipe 3 to connect the flange 4 and the branch pipe 3 in an adhesive form.

The flange 4 and the branch pipe 3 are connected to each other by the head 1 of the bolt 11 which is fastened to the peripheral edge of the connecting hole 9.
It is mechanically coupled by 1a. That is, the protrusion 4a is formed on the peripheral edge of the connection hole 9 of the flange 4 similarly to the peripheral edge portion 2c of the surge tank 2. And
A groove 10 is formed in the inner peripheral area of the protrusion 4a, and the outer protrusion 3c is fitted in the groove 10. Bolt 1
1 is fastened to the protrusion 4a on the outer peripheral side of the groove 10,
As shown in (B), the head portion 11a is adapted to retain the outer projection 3c fitted in the groove 10.

In such an intake manifold, the connection strength between the surge tank 2 and the branch pipe 3 depends on the adhesive force of the thermosetting resin adhesive 6 to the recess 7 in the surge tank 2 in the tip region of the end 3a. Since the structural coupling force due to the fitting is added, a solid connection form that can be practically used is achieved. Further, the connection strength between the flange 4 and the branch pipe 3 is determined by the adhesive force of the thermosetting resin adhesive 8 and the mechanical coupling force of the head 11a of the bolt 11 that holds the outer projection 3c of the branch pipe 3 together. A connection form similar to the connection with the surge tank 2 is achieved.

Next, the manufacturing process of the intake manifold will be described. The surge tank 2 is manufactured by casting a general aluminum alloy such as AC2B and AC4C. The casting surge tank 2 is provided with an opening 2a, a connection hole 5, and other necessary parts. The flange 4 is also made of the same material by casting.

The branch pipe 3 is manufactured by manufacturing an aluminum pipe having both ends opened by hot extrusion or the like, and bending the aluminum pipe into a predetermined shape. As a material for the branch pipe 3, an aluminum alloy such as A6063 is used. The outer projection 3c is formed by beading, but the ring member may be welded as another method. Subsequently, the thermosetting resin adhesives 6 and 8 are applied to the outer peripheral surfaces of the both ends 3a and 3b of the branch pipe 3 with a spatula or a micro dispenser, and one end 3a is connected to the connection hole of the surge tank 2. 5, the tip area is 7m inside the cavity of surge tank 2.
Insert so that it projects about m. Further, the tip end region of the end portion 3a protruding into the cavity is expanded by a rotating roll inserted through the opening 2a to be expanded in diameter and fitted into the recess 7.

Further, the other end 3b is inserted into the connecting hole 9 of the flange 4 until the outer projection 3c fits into the groove 10 at the peripheral edge of the connecting hole 9 and contacts the bottom surface thereof. Next, the protrusion 4
A screw hole is formed in a and the bolt 1
0 is fastened and the outer protrusion 3c is locked by the head 11a. The intake manifold in which the branch pipe 3, the surge tank 2 and the flange 4 are mechanically connected to each other as described above is 180 °
The thermosetting resin adhesives 6 and 8 are left to stand in a hot atmosphere for about 20 minutes to be heat-cured. As a result, the branch pipe 3, the surge tank 2 and the flange 4 are completely integrated.

As the thermosetting resin adhesives 6 and 8, an epoxy resin adhesive or the like can be used.
As described above, in the intake manifold according to the present embodiment, since the brazing process can be eliminated, the surge tank 2 and the flange 4 are not exposed to the high temperature (580 ° C.) of brazing heating, and a general aluminum alloy can be used. Therefore, it has excellent characteristics such as that die casting can be adopted and deformation due to thermal strain is small.

Further, when the branch pipe 3 is connected to the surge tank 2, the diameter of the tip portion of the end portion 3a is expanded, but the heat generated during this processing can preheat the thermosetting resin adhesive material 6. It is also a great advantage that the preheating step before the heat curing step of the adhesive material 6 is unnecessary. As another embodiment, the connection form between the surge tank and the branch pipe may be used for connecting the flange and the branch pipe, or conversely, the connection form between the flange and the branch pipe may be changed to the surge tank and the branch pipe. You may use it for connection with a pipe.

[Brief description of drawings]

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

2A and 2B show how a surge tank and a branch pipe are connected according to the above embodiment, FIG. 2A is a sectional view showing a state in which a branch pipe end is inserted into a connection hole, and FIG. 2B is an end tip region. It is sectional drawing which shows the state which expanded the diameter.

3A and 3B show how the flange and the branch pipe are connected to each other according to the above embodiment, FIG. 3A is a cross-sectional view showing a processing mode of the end of the branch pipe, and FIG. FIG. 3 is a plan view showing a state in which a bolt is fastened, and FIG.

[Explanation of symbols]

1 ... Intake manifold, 2 ... Surge tank, 3 ... Branch pipe, 4 ... Flange, 5, 9 ... Connection hole, 6, 8 ... Thermosetting resin adhesive, 11 ... Bolt, 11a ... Head.

Claims (2)

[Claims] 1. An intake manifold comprising a surge tank made of cast aluminum, a flange connected to an intake hole portion of an engine, and a plurality of branch pipes having one end connected to the surge tank and the other end connected to the flange. An end portion of the branch pipe is inserted into at least one of a connection hole formed in the surge tank and a connection hole formed in the flange corresponding to each branch pipe, and the connection hole wall surface And the outer peripheral surface of the end portion are adhered to each other by a thermosetting resin adhesive, and the end region of the end portion of the branch pipe protruding from the connection hole is expanded in diameter from the connection hole to engage with the peripheral portion. Intake manifold characterized by being stopped. 2. An intake manifold comprising: a surge tank made of cast aluminum; a flange connected to an intake hole portion of an engine; and a plurality of branch pipes having one end connected to the surge tank and the other end connected to the flange. An outer protrusion is formed in the middle of each branch pipe, and at least one of the connection hole formed in the surge tank and the connection hole formed in the flange corresponding to each branch pipe, The end of the branch pipe is inserted in a state where the outer protrusion is in contact with the peripheral edge of the connecting hole, and the wall surface of the connecting hole and the outer peripheral surface of the end are thermosetting resin adhesive materials. An intake manifold characterized in that a bolt for fastening the outer projection with a head is fastened to the peripheral portion of the connecting hole.