JPH084608A - Structure of intake manifold - Google Patents

Abstract

PURPOSE:To dispense with any complicated welding process by inserting the upstream parts of pipes into insertion holes of a surge tank attaching flange, arranging seal members in the clearances between the upstream flares and the surge tank, and fastening a fastener in this state, and pinching the upstream flares of the pipes. CONSTITUTION:The upstream parts of pipes 4a, 4b, 4c are fastened by bolts 26a, (26b, 26c), 26d inserted into bolt insertion holes 33a, (33b, 33c, 33d) of a surge tank attaching flange and nuts 34a, (34b, 34c), 34d in the state where they are inserted into circular holes 32a (32b, 32c) of the surge tank attaching flange 3. Thereby, the upstream flares 41a, 41b, 41c of the pipes 4a, 4b, 4c are pressed to and pinched between the pinching surfaces of a surge tank 2 through O-rings 61a, 61b, 61c. At this time, the upstream flares 41a, 41b, 41c are housed into a stepped part 24 provided on the surge tank 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intake manifold structure for supplying air from a throttle body to an engine.

[0002]

2. Description of the Related Art An automobile engine is provided with an intake manifold for evenly distributing a mixture of air and fuel to each port of the engine. As a conventional intake manifold, a die-cast aluminum alloy has been known. Although aluminum alloy has the advantages of being lighter in weight because of its low specific gravity and being excellent in corrosion resistance, the cost per material is high due to its high unit price, and the thickness increases in the case of die-cast molded products. The amount of material used increased and the material cost increased.

Therefore, in order to reduce the manufacturing cost by reducing the amount of aluminum alloy used, an intake manifold in which a plurality of aluminum alloy pipes are welded to a surge tank or an engine head mounting flange instead of the die-cast molded product is used. Is being developed.

[0004]

However, since the process of welding and joining is complicated, the manufacturing cost is increased, and when welding distortion occurs, leakage occurs or durability is affected. was there.

Although the cost of the aluminum alloy pipe is lower than that of the die-cast molded product, the production cost cannot be sufficiently reduced because the unit cost of the aluminum alloy itself is high. . Considering this point, it is possible to use an inexpensive iron or iron alloy pipe instead of the aluminum alloy pipe. However, since iron or iron alloy pipes have poor corrosion resistance, i.e., rust resistance, if rust occurs on the inner surface of the pipe, the rust may be sent to the port part of the engine together with the intake air and damage the inner surface of the cylinder, damaging the engine. there were. For this reason, intake manifolds using pipes made of iron or iron alloy have not been put into practical use until now.

With regard to the intake manifold using the iron or iron alloy pipe, rust is often generated particularly at the joint with the surge tank. In other words, since this welded portion is usually welded by arc welding, weld beads or blowholes may occur, and even if plating is applied to that portion, it is almost impossible to cover and rust occurs from there. was there.

The present invention has been made in view of the above problems, and an object of the present invention is to provide an intake manifold structure which is inexpensive to manufacture and easy to assemble.

[0008]

In order to solve the above problems, the invention according to claim 1 fastens a mounting hole provided in a surge tank connected to a throttle body and a pipe for supplying intake air to an engine. In the structure of the intake manifold fastened by a tool, the outward flare upstream flare provided at the upstream end of the pipe, the mounting hole of the surge tank and the upstream flare of the pipe A seal member arranged in the gap, an insertion hole for inserting the upstream side of the pipe, and a surge tank mounting flange for sandwiching the upstream flare together with the surge tank by fastening the fastener. Is characterized by.

According to a second aspect of the present invention, there is provided the intake manifold structure according to the first aspect, wherein the surge tank and the surge tank mounting flange hold at least one of both holding surfaces for holding the upstream flare. A stepped portion capable of accommodating the upstream flare is provided.

The invention according to claim 3 is the structure of the intake manifold according to claim 1 or 2, wherein the surge tank, the pipe and the flange for mounting the surge tank are iron or iron alloy coated with a corrosion resistant metal. It is characterized by being formed in.

A fourth aspect of the present invention is the intake manifold structure according to the first or second aspect, wherein the surge tank is made of resin, and the pipe and the surge tank mounting flange are covered with a corrosion-resistant metal. It is characterized in that it is formed of iron or iron alloy.

Further, in the intake manifold according to any one of claims 1 to 4, the downstream side flare in which the downstream end of the pipe is formed in an outward flange shape is inserted through the downstream side of the pipe. A port portion mounting flange that has an insertion hole and that holds the downstream flare together with the port portion of the engine by fastening the port portion fastener may be provided.

At this time, a stepped portion capable of accommodating the downstream flare may be provided on at least one of both sandwiching surfaces on which the port portion of the engine and the port portion mounting flange sandwich the downstream flare. The port mounting flange may be made of iron or iron alloy coated with a corrosion resistant metal.

[0014]

According to the invention described in claim 1,
Insert the upstream side of the pipe into the insertion hole of the surge tank mounting flange, place the seal member in the gap between the upstream flare and the surge tank, and fasten the fastener in this state to fasten the surge tank mounting flange and surge tank. Holds the upstream flare of the pipe with the side. By adopting such a non-welded structure, complicated welding process is not required, assembly is easy and manufacturing cost is reduced by that amount, and adverse effects due to welding, such as deterioration of durability and leakage due to welding distortion, are eliminated. it can. Further, it is possible to reduce the plate thickness as compared with die casting, and it is possible to reduce the manufacturing cost by reducing the amount of materials used.

According to the second aspect of the present invention, when the fastener is fastened by the fastener, the upstream flare is housed in the step portion, so that the surge tank and the surge tank mounting flange are mutually held on the sandwiching surface other than the step portion. The abutting force causes the flange for mounting the surge tank to evenly apply the clamping force for clamping the upstream flare. Therefore, the fastening work can be performed quickly and reliably. On the other hand, if the recess is not formed, a gap corresponding to the thickness of the upstream flare is formed between the surge tank and the surge tank mounting flange when they are fastened by the fastener, so that they do not come into contact with each other. The clamping force with which the surge tank mounting flange clamps the upstream flare may be partially biased.

According to the third aspect of the invention, since the surge tank, the pipe and the flange for mounting the surge tank are made of iron or an iron alloy coated with a corrosion resistant metal, the material cost is lower than that of the aluminum alloy, The manufacturing cost can be reduced. Further, rust does not occur on these, and rust does not occur from the joint portion of the non-welded structure. Therefore, damage to the engine due to rust can be reliably prevented. Incidentally, the iron alloy is an alloy containing iron as a main component,
It is meant to include soft iron and mild steel.

According to the invention described in claim 4, since the surge tank is made of resin, it can be easily formed even in a complicated shape, further weight reduction can be achieved, and noise can be reduced. It also has an effect. Other functions are similar to those of the invention of claim 3.

When the intake manifold according to any one of claims 1 to 4 is provided with the downstream flare and the flange for mounting the port portion, the mounting structure for the port portion of the engine is the port portion of the engine. And a downstream side flare, a downstream side seal member is arranged in the gap, and the downstream side flare is held together with the port part of the engine by fastening the port portion mounting flange with the port portion fastener. In this way, since the welded part with the engine port has also adopted a non-welded structure, a complicated welding process is not required for this welded part, and the assembly is easy and the manufacturing cost is correspondingly reduced. It is possible to eliminate adverse effects such as deterioration of durability and leakage due to welding distortion.

Further, in the case where the step portion capable of accommodating the downstream flare is provided on at least one of both sandwiching surfaces for sandwiching the downstream flare by the port portion of the engine and the port portion mounting flange, the port portion is provided. Since the clamping force by which the mounting flange clamps the downstream flare is evenly applied, the fastening work can be performed quickly and reliably.

Further, when the port mounting flange is formed of iron or iron alloy coated with a corrosion resistant metal,
The material cost is lower than that of aluminum alloy, and the manufacturing cost can be reduced. Moreover, rust does not occur on the port mounting flange itself, and rust does not occur at the joint portion of the non-welded structure. Therefore, damage to the engine due to rust can be reliably prevented.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described below with reference to the drawings. 1 to 5 are explanatory views of the intake manifold. 1 is a front view, FIG. 2 (a) is a sectional view taken along line AA of FIG. 1, and FIG. 2 (b) is an E view of FIG. 2 (a) (only the surge tank is shown). FIG. 3 is BB of FIG.
It is sectional drawing. 4A is a cross-sectional view taken along the line CC of FIG.
(B) is a DD sectional view of FIG. 1. FIG. 5A is FIG.
5 is a sectional view taken along line F-F in FIG. 5, and FIG. 5B is a partially enlarged view of FIG. FIG. 6 is a front view of the surge tank mounting flange.

The intake manifold 1 includes a surge tank 2, a surge tank mounting flange 3, and three pipes 4.
It is composed of a, 4b, 4c, and a port portion mounting flange 5. The surge tank 2 has a substantially cylindrical hollow portion 2.
It is composed of a tank portion 21 having 9 and a flange portion 15 projecting rearward of the upper portion of the tank portion 21. The tank portion 21 and the flange portion 15 are integrally formed of nylon resin.

A lid 21a is adhered to the left side surface of the tank portion 21. The tank portion 21 is made of nylon resin having a thickness of 3.5 mm including the lid 21a. However, the bottom surface 23 of the tank portion 21 has a wall thickness of about 7 mm. Tank part 2
On the bottom surface 23 of 1 is a surge tank mounting flange 3 which will be described later.
A sandwiching surface 22 having a shape substantially corresponding to is formed. On the sandwiching surface 22, a step portion 24 recessed from the bottom surface 23,
Clamping surfaces 25a, 25b, 25c having the same height as the bottom surface 23,
25d are formed. The steps of the step portion 24 are formed by the upstream flares 41a, 41 of the pipes 4a, 4b, 4c described later.
It is set to be slightly smaller than the plate thicknesses of b and 41c. Bolts 26a, 26b, which are galvanized as corrosion-resistant metal coatings, are attached to the pressing surfaces 25a, 25b, 25c, 25d.
26c and 26d are buried. Further, in the step portion 24, circular holes 27a, 27b, and
27c are provided, and circumferential grooves 28a, 28b, 28c into which O-rings 61a, 61b, 61c as seal members are fitted are provided around each of them.

The flange portion 15 has a communication hole 16 for communicating the throttle body (not shown) with the cavity portion 29 of the tank portion 21, and the flange surface 17 contacting the throttle body has bolts at a total of four locations. Insertion holes 18a, 18b,
18c and 18d are provided, and are fixed to the throttle body by bolts (not shown) inserted through them.
The throttle body refers to a device including a throttle valve that interlocks with the accelerator, a throttle position sensor that detects the opening of the throttle valve, and the like.

The surge tank mounting flange 3 is formed by processing a mild steel plate having a thickness of 2.6 mm (JIS standard SPH270C) into a shape in which three circles are connected, and the entire surface is made of nickel by electroless nickel phosphorus plating. A phosphorus coating is formed (see FIG. 6). The surge tank mounting flange 3 has circular holes 32a, 32b, left, middle, and right, respectively.
32c is provided, and bolt insertion holes 33 are provided at a total of 4 places.
a, 33b, 33c, 33d are provided. The flange 3 for mounting the surge tank has a flange surface 31 on the back side in FIG.
The upstream flares 41a, 41b, and 41c are pressed against the surge tank 2 to be sandwiched. Therefore, the flange surface 31 corresponds to the sandwiching surface of the surge tank mounting flange of the present invention.

The port mounting flange 5 has a thickness of 2.6.
mm mild steel plate (SPH270C), elliptical holes 51a, 51b, 51c are provided on the left, middle, and right, respectively.
Cylindrical portions 52a, 52b and 52c are provided so as to project around each of them. Further, a folded-back portion 53 is provided on the peripheral edge of the port portion mounting flange 5 in the same direction as the protruding direction of the tubular portions 52a, 52b, 52c. This cylindrical portion 52a, 52
Due to the b and 52c and the folded portion 53, the port mounting flange 5 has sufficient rigidity even if the plate thickness is thin. The port mounting flange 5 has a nickel phosphorus coating formed on its entire surface by electroless nickel phosphorus plating.

Further, at a total of five places of the port portion mounting flange 5, there are compression surfaces protruding toward the engine side (not shown), that is, the side opposite to the folded-back portion 53, from the flange surface 54 corresponding to the rear surface side in FIG. 55a, 55b, 55c, 55d, 55
e is formed (see FIG. 4). This pressing surface 55a,
The steps between 55b, 55c, 55d and the flange surface 54 are
Downstream flares 42a of pipes 4a, 4b, 4c, which will be described later,
It is set to be slightly smaller than the plate thicknesses of 42b and 42c. The pressing surfaces 55a, 55b, 55c, 55d, 55
In e, bolt insertion holes 56a, 56b, 56c, 56d,
56e is provided.

The three pipes 4a, 4b and 4c are each a mild steel pipe (J) having a thickness of 1.0 mm and a diameter of 28.6 mm.
The IS standard STKM11A) has a nickel phosphorus coating formed by electroless nickel phosphorus plating on the entire surface. The electroless nickel phosphorous plating refers to autocatalytic nickel phosphorous plating by reduction of hypophosphorous acid, and the nickel phosphorous coating formed by this contains nickel as a main component and contains 2 to 15% of phosphorus. Such electroless nickel-phosphorus plating is characterized in that the nickel-phosphorus coating is formed uniformly and reliably on the inner surfaces of the pipes 4a, 4b, 4c, as compared with electroplating or the like. Therefore, as compared with the case where the metal coating is formed by electroplating or the like, it is possible to more reliably prevent the generation of rust on the inner surface of the pipe.

Outward flanged flares 41a, 41b and 41c are formed on the upstream end of the pipe. The upstream sides of these pipes 4a, 4b and 4c are circular holes 32a, 32b and 32c of the surge tank mounting flange 3.
Bolts 26a, 26b, 26c, 26d and nuts 34 inserted into the bolt insertion holes 33a, 33b, 33c, 33d of the surge tank mounting flange 3 with the nuts 34 inserted.
It is fastened by a, 34b, 34c and 34d.
As a result, the upstream flares 41a, 41b, 41c are O
Surge tank 2 via rings 61a, 61b, 61c
It is pressed and pinched by the pinching surface 22. At this time, the upstream flares 41 a, 41 b, 41 c are stored in the step portion 24 provided in the surge tank 2. Therefore, the surge tank mounting flange 3 is attached to the pressing surfaces 25a, 2 of the surge tank 2 by
5b, 25c, 25d can be fastened in contact with each other, whereby each upstream flare 41a, 41b, 41
The c is clamped by the surge tank mounting flange 3 with a substantially uniform clamping force. The nuts 34a, 34b, 34
C and 34d are galvanized as corrosion resistant metal coatings.

On the other hand, the downstream side of the pipe is deformed to have an elliptical cross section, and its end portion has an outward brim-shaped downstream flare 42.
a, 42b, 42c are formed. The downstream side of these pipes 4a, 4b, 4c is provided with a port mounting flange 5
Cylindrical portions 52a, 52b, 52c and elliptical holes 51a, 51
b, 51c, and downstream flares 42a, 42b, 4
2c and a port portion (not shown) of the engine with a gasket 62 (see FIG. 4 (a)) as a seal member arranged in the gap, bolt insertion holes 56a, 56b, 56c of the flange 5 for mounting the port portion. , 56d, 56e are fastened by bolts (not shown). This allows
The downstream flares 42a, 42b, 42c are gaskets 62.
It is pressed and pinched by the engine port through the.
At this time, the downstream flares 42a, 42b, 42c are housed in the flange surface 54 recessed from the clamping surfaces 55a, 55b, 55c, 55d, 55e. Therefore, the tightening surfaces 55a, 55b, 55c, 55 of the port mounting flange 5 are
d and 55e come into contact with the engine port portion, whereby each downstream flare 42a, 42b, 42c.
Are clamped with a substantially uniform clamping force.

When the intake manifold 1 having the above structure is used, the three elliptical holes 31a, 31b, 31c of the port mounting flange 5 are aligned with the respective port portions of the engine (not shown), and the surge tank 2 has the same shape. Flange part 1
The communication hole 16 of No. 5 is aligned with a throttle body (not shown). Therefore, the air sucked from the air cleaner (not shown) is introduced into the port portion of the engine through the surge tank 2 and the pipes 4a, 4b, 4c.

The effects of the above intake manifold will be described below. Since a non-welded structure is adopted for the joints between the pipes 4a, 4b and 4c and the surge tank 2 and the joints between the pipes 4a, 4b and 4c and the engine port, a complicated welding process is not required and assembly is easy. In addition, the manufacturing cost can be reduced by that amount, and at the same time, adverse effects caused by welding, such as deterioration of durability and leakage due to welding distortion, can be eliminated. Further, the intake manifold 1 can be made thinner than die cast molding, and the manufacturing cost can be reduced by reducing the amount of material used. When the surge tank mounting flange 3 is fastened to the surge tank 2, the upstream flares 41a, 41b, 41c are accommodated in the step portion 24 provided in the surge tank 2, so that the flange surface 31 of the surge tank mounting flange 3 is The clamping force for clamping the upstream flare 41a, 41b, 41c by the surge tank mounting flange 3 is evenly applied to the surge tank 2 by coming into contact with the pressing surfaces 25a, 25b, 25c, 25d of the surge tank 2. Therefore, there is no possibility that the clamping force is partially biased at the time of fastening, and the fastening work can be performed quickly and reliably. Even when the port mounting flange 5 is fastened, the fastening surfaces 55a, 55 having a step with the flange surface 54 are formed.
Due to the presence of b, 55c, 55d, the same effect can be obtained. Since the pipes 4a, 4b, 4c, the surge tank mounting flange 3 and the port mounting flange 5 are made of mild steel plated with nickel-phosphorus, the material cost is lower than that of aluminum alloy and the manufacturing cost is reduced. Can be planned. Further, rust does not occur on these, and rust does not occur from the joint portion of the non-welded structure. Therefore, damage to the engine due to rust can be reliably prevented. Since the surge tank 2 is made of resin, even if it has a complicated shape, it can be easily formed, further weight reduction can be achieved, and noise can be reduced.
Since the pipe is in contact with the engine and is easily affected by heat, it is difficult to make it from resin, while the surge tank is far from the engine and is not easily affected by heat, so it is not made of resin. can do.

It is needless to say that the present invention is not limited to the above embodiments and can be carried out in various modes without departing from the technical scope of the present invention. For example, as another example of the corrosion-resistant metal coating, a so-called dacrotized treatment of forming a zinc chromic acid composite coating by baking may be adopted. In the dacrotized treatment, the pipe before surface treatment is immersed in a dacro liquid containing metallic zinc flakes, chromic anhydride, glycol, etc.
Heat to 350 ° C. As a result, hexavalent chromium is reduced by an organic substance such as glycol, and water-insoluble amorphous 3
A chromium-valent polymer is generated, and this serves as a binder to bind together the zinc flakes laminated in several tens of layers to form a corrosion-resistant metal coating. Also by this dacrotizing treatment, a film can be formed uniformly and surely particularly on the inner surface of the pipe as compared with electroplating.

Although the surge tank 2 made of resin is used in the above embodiment, a surge tank made of iron or iron alloy having a corrosion resistant metal coating formed by electroless plating may be used. Further, although the step portion 24 capable of accommodating the upstream flare 41a, 41b, 41c is provided in the above embodiment, the upstream flare 41 is not provided even if the step portion 24 is not provided.
The joints a, 41b, 41c and the surge tank 2 can be made sufficiently airtight, and there is no practical problem.

Furthermore, in the above embodiment, the surge tank 2
Although the stepped portion 24 is provided on the holding surface 22 of, the stepped portion may be provided on the flange surface 31 of the surge tank mounting flange 3 instead of or together with the stepped portion 24.

[Brief description of drawings]

FIG. 1 is a front view of an intake manifold.

2 is an explanatory view of the intake manifold, and FIG.
1A is a cross-sectional view taken along the line AA of FIG. 1, and FIG. 2B is FIG. 2A.
FIG. 7 is an E view (showing only a surge tank).

FIG. 3 is a sectional view taken along line BB of FIG.

4 is an explanatory view of the intake manifold, and FIG.
1A is a sectional view taken along the line CC of FIG. 1, and FIG. 4B is a line D- of FIG.
It is a D sectional view.

5 is an explanatory view of the intake manifold, and FIG.
5A is a sectional view taken along line F-F in FIG. 3, and FIG.
FIG.

FIG. 6 is a front view of a surge tank mounting flange.

[Explanation of symbols]

1 ... Intake manifold, 2 ... Surge tank, 3 ... Surge tank mounting flange, 4a-
c ... pipe, 5 ... port part mounting flange,
22 ... sandwiching surface, 24 ... stepped portion,
25a-d, 55a-d ... Clamping surface, 31, 5
4 ... Flange surface, 41a-c ... Upstream flare, 42a-c ... Downstream flare, 61a
~ C ... O-ring,

Claims (4)

[Claims] 1. A structure of an intake manifold in which a mounting hole provided in a surge tank connected to a throttle body and a pipe for supplying intake air to an engine are fastened by a fastener, and an upstream end portion of the pipe. An upstream flare in the form of an outward flange, a seal member arranged in the gap between the mounting hole of the surge tank and the upstream flare of the pipe, and an insertion hole for inserting the upstream side of the pipe. And a surge tank mounting flange for sandwiching the upstream flare together with the surge tank by fastening the fastener, and a structure for an intake manifold. 2. A step portion capable of accommodating the upstream flare is provided on at least one of both sandwiching surfaces where the surge tank and the surge tank mounting flange sandwich the upstream flare. The structure of the intake manifold according to item 1. 3. The structure of the intake manifold according to claim 1, wherein the surge tank, the pipe, and the flange for mounting the surge tank are formed of iron or an iron alloy coated with a corrosion resistant metal. 4. The surge tank is formed of resin, and the pipe and the surge tank mounting flange are formed of iron or iron alloy coated with a corrosion resistant metal. Structure of intake manifold.