JPH09126072A - Air intake manifold of v-type 2-cylinder engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the number of parts in an air intake manifold of a V-type two-cylinder engine, to facilitate the connection work, to easily and correctly position an air intake port to an air intake manifold, and to provide the manifold easy to absorb the vibration of the engine and difficult to transfer the vibration to a carburetor. SOLUTION: An air intake manifold 7 of a V-type 2-cylinder engine provided with one carburetor 6 in a v-shaped valley between two cylinders 3 is integratedly provided with a forked air intake manifold body 7a to connect the carburetor 6 to an air intake port of two cylinder heads, and a carburetor holder to connect the air intake manifold body 7a to a mixture feeding port 6a of the carburetor 6, and the manifold is made of elastic material.

Description

Detailed Description of the Invention

[0001]

The present invention relates to an intake manifold for connecting a carburetor and two intake ports in a V-type two-cylinder engine having one carburetor in a V-shaped valley between two cylinders.

[0002]

2. Description of the Related Art An intake manifold 50 of this type is shown in FIG.
As shown in FIGS. 5 (a) to 5 (c), an intake port 53a of each cylinder head 52 is connected through a connection port 50a with the carburetor 51.
The connection port 50b is formed in a forked shape, and a flange 50c is integrally formed on the outer periphery of each connection port 50b. Since the intake manifold 50 is usually formed of a metal material such as an aluminum alloy, and the cylinder head 52 is also formed of a metal material such as an aluminum alloy, as shown in FIG. Is provided with an O-ring 54 to prevent gas leakage. As shown in FIG. 5C, a rubber cab holder 5 is provided around the connection portion of the intake manifold 50 with the mixture supply port 51a of the carburetor 51.
5 are fitted and fastened by two band-shaped clamp members 56 wound around the outer periphery of the cab holder 55. In addition, as a related technique, there is an air supply connection pipe described in Japanese Utility Model Laid-Open No. 58-148259.

However, the structure of the above-mentioned conventional intake manifold 50 has the following disadvantages.

[0003] A separate cab holder is required for connection to the carburetor, and an O-ring for sealing is required for connection to the intake port of the cylinder head.
In addition to the large number of parts, the individual connection work is troublesome.

In order to assemble the cylinder on the crankcase and stack the cylinder head thereon, the position of the center axis between the intake port and the opening on the intake manifold side due to the dimensional tolerance of those parts. Although the displacement is likely to occur, it is difficult to absorb the displacement because the intake manifold and the cylinder head are both formed of a metal material, and disadvantageous in terms of performance.

[0005] Since the vibration of the engine is directly transmitted to the carburetor via the metal member, there is a possibility that malfunction of the carburetor may occur or durability may be reduced.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and has the following effects: reduction in the number of parts; facilitation of connection work; easy and accurate positioning of an intake port and an intake manifold; It is an object of the present invention to absorb and to make it difficult to transmit to a carburetor.

[0007]

In order to solve the above problems, an intake manifold for a V-type 2-cylinder engine according to the present invention comprises: a) a V-type 2 equipped with one carburetor in a V-shaped valley between two cylinders. In an intake manifold of a cylinder engine, b) A bifurcated intake manifold main body that connects the carburetor to the intake ports of the two cylinders or the cylinder head, and connects the intake manifold main body and the air-fuel mixture supply port of the carburetor. It is integrated with the cab holder and is formed of an elastic member.

By integrating the intake manifold main body and the cab holder, the number of parts is reduced and the conventional cab holder is not required, so that the connecting work to the carburetor is simplified. In addition, the intake manifold is made of elastic material such as rubber to make it deformable,
The positional deviation between each intake port and the opening of the intake manifold can be corrected by the deformation of the intake manifold, and the intake manifold and the intake manifold can be connected so that their central axes coincide with each other. Further, since the intake manifold acts as a kind of cushioning member and absorbs the vibration from the engine, the vibration is hardly transmitted to the carburetor.

As described in claim 2, c) a holder made of metal or hard synthetic resin may be attached to the side of the intake manifold main body that is connected to the intake port. The holder can be integrally mounted by casting it when molding the intake manifold.

According to this intake manifold, the cylinder or the cylinder head is attached to the intake port via the holder, so that the connection is ensured.

As described in claim 3, d) an annular projection made of an elastic member is integrally provided at the opening end of the intake manifold main body on the side of connection with the intake port, and the annular projection is provided around the intake port. It is desirable to provide a groove.

According to this intake manifold, when the cylinder or the cylinder head is attached to the intake port, the annular projection on the intake manifold body side is fitted and positioned in the annular groove around the intake port, and between them. A sealing property is generated in the connection portion, and the same action as that of the O-ring is obtained.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an intake manifold for a V-type two-cylinder engine according to the present invention will be described below with reference to the drawings.

FIG. 1 shows a V-type 2 having one carburetor.
FIG. 2 is a side view showing a cylinder engine, FIG. 2 is a side view showing a state in which the intake manifold of the present embodiment is connected to a carburetor,
FIG. 3A is a rear view of the intake manifold, and FIG.
FIG. 3 (a) is a view in the direction of arrow b, FIG. 3 (c) is a view in the direction of arrow c in FIG. 3 (a), FIG. 4 (a) is a front view of a metal holder for connecting the intake port, FIG. Is a side view thereof, and FIG. 4 (c) is cc in FIG. 4 (a).
It is a line sectional view.

As shown in FIG. 1, a V-type two-cylinder engine 1 of the present embodiment is mounted on a crankcase 2 in front and rear (or left and right) directions.
Two cylinders 3 are arranged upward in a V shape, a cylinder head 4 is assembled on each cylinder 3, and a head cover 5 is mounted on the cylinder head 4. One carburetor 6 is arranged in an upper part in a V-shaped valley (zone) formed by the two cylinders 3 and the cylinder head 4. As shown in FIG. 2, an air cleaner AC is connected to an air intake port 6b of the carburetor 6 via a rubber duct T, and a mixture supply port 6a on the opposite side and an intake port 4a of each cylinder head 4 (see FIG. 2). 3) is connected by the intake manifold 7.

As shown in FIG. 2, a conventional cab holder 5 connected to a forked intake manifold body 7a and a mixture supply port 6a of a carburetor 6, as shown in FIG.
5 (see FIG. 5), and is formed of an elastic member such as rubber or soft synthetic resin having excellent oil resistance. That is, an annular concave groove 6c formed on the outer peripheral surface of the mixture supply port 6a of the carburetor 6 is formed on the inner peripheral surface of the end of the opening 7A of the manifold body 7a on the side connected to the mixture supply port 6a of the carburetor 6. Fitting part 7b that can be fitted to
Are formed in an annular shape. A concave groove 7c for holding the band-shaped clamp member 8 is formed on the outer peripheral surface of the end of the opening 7A. The carburetor 6 and the intake manifold 7 are integrally connected by tightening the clamp member 8 with the fitting portion 7b of the manifold body 7a fitted in the concave groove 6c of the carburetor 6.

As shown in FIGS. 2 and 3A, a concave groove 7d is formed in the outer peripheral surface of the two ends of the two openings 7B on the opposite side of the intake manifold body 7a.
A protrusion 7e is formed in a part of the inside as shown in FIG. The protrusion 7e is for positioning a holder 9 described later for connection with the cylinder head 4 and for preventing rotation. As shown in FIG. 3, the holder 9 includes a fitting portion 9a that can be fitted into the concave groove 7d and a protrusion 7 on a part of the fitting portion 9a.
e and a recess 9b that can be fitted to the ring body are formed by ring bodies provided on the inner peripheral surface, and substantially triangular projections 9c are formed on both sides of the ring body, and bolt holes 9 are formed in each projection 9c.
d. In this embodiment, the holder 9 is die-cast from an aluminum alloy. However, the holder 9 may be formed of not only a metal material but also a synthetic resin as long as it is a hard material. As shown in FIGS. 3A and 3B, the holder 9 is mounted on the concave groove 7d of the intake manifold 7 by aligning the recess 9b with the projection 7e and fitting the fitting portion 9a. You.

Although the holder 9 is manufactured separately from the intake manifold 7, the holder 9 is manufactured in advance and then cast into a mold when the intake manifold 7 is formed. Can be integrally mounted around the ends of the two openings 7B.

The opening 7 on the connection side of the intake manifold body 7a with the intake port 4a (FIG. 3A) of the cylinder head 4.
An annular projection 7f is integrally provided on the end face B with an elastic member made of the same material as the main body 7a. On the other hand, intake port 4
An annular groove 4c corresponding to the annular protrusion 7f is provided around the periphery of a, so that the positioning when connecting the intake manifold 7 to the intake port 4a also serves as a sealing member, and an O-ring is unnecessary. For connection to each intake port 4a, a bolt 10 is inserted through a bolt hole 9d of the holder 9,
It is made firm by screwing it into the screw hole 4e on the cylinder head 4 side and tightening it. Therefore, the intake port 4
Even when the center axis line is deviated between a and the opening 7B of the intake manifold 7, the intake manifold 7 is deformed and coincides with each other in the connected state. Further, between the carburetor 6 and the cylinder head 4, an intake manifold 7 made of an elastic member is provided.
And the carburetor 6 and the air cleaner A
Since the rubber tube T is also interposed on the C side, the carburetor 6 is supported at the center by a plurality of elastic members, and the vibration of the engine is not transmitted to the carburetor 6. As a result, the carburetor 6 does not vibrate during operation of the engine and the condition does not deteriorate, and the durability does not deteriorate.

[0020]

As is apparent from the above description,
The intake manifold of the V-type two-cylinder engine according to the present invention has the following effects.

(1) Since the intake manifold body and the cab holder are integrated, the number of parts is reduced and the work of connecting to the carburetor is simplified. Further, since the intake manifold is formed of an elastic member such as rubber, the positional deviation between each intake port and the opening of the intake manifold is corrected, and the central axes of both can be aligned and connected. Further, since the intake manifold acts as a kind of cushioning member and absorbs the vibration from the engine, the vibration is hardly transmitted to the carburetor.

(2) In the intake manifold according to the second aspect, the attachment to the intake port of the engine is performed via the holder, so that the connection is reliable and easy.

(3) In the intake manifold according to the third aspect of the invention, when the engine is attached to the intake port of the engine, the annular projection on the intake manifold body side is fitted into the annular groove around the intake port and positioned, and A sealing property is generated in the connection portion between them, an O-ring is not required, and connection work is simplified.

[Brief description of the drawings]

FIG. 1 is a side view showing a V-type two-cylinder engine having an intake manifold of the present invention and one carburetor.

FIG. 2 is a side view showing a state where the intake manifold according to the embodiment of the present invention is connected to a carburetor.

FIG. 3 (a) is a rear view of the intake manifold, and FIG.
FIG. 3B is a view in the direction of arrow b in FIG. 3A, and FIG. 3C is a view in the direction of arrow c in FIG. 3A.

4 (a) is a front view of a metal holder for connecting an intake port, FIG. 4 (b) is a side view thereof, and FIG. 4 (c) is c- in FIG. 4 (a).
It is a c line sectional view.

FIG. 5 (a) is a plan view of a conventional intake manifold,
FIG. 5B is a front view showing a part connected to the intake port in a cross section, and FIG. 5C is a side view showing a part connected to the carburetor in a cross section.

[Explanation of symbols]

 Reference Signs List 1 V-type two-cylinder engine 4 Cylinder head 6 Carburetor 7 Intake manifold 7a Intake manifold body 7d Concave groove 7e protrusion 8 Clamp member 9 Holder

Claims (3)

[Claims] 1. An intake manifold for a V-type two-cylinder engine having one carburetor in a V-shaped valley between two cylinders, wherein the two-forked shape connects the carburetor and the intake ports of the two cylinders or cylinder heads. An intake manifold for a V-type two-cylinder engine, characterized in that the intake manifold main body and a cab holder connecting the intake manifold main body and the air-fuel mixture supply port of the carburetor are integrated and formed of an elastic member. 2. The intake manifold for a V-type two-cylinder engine according to claim 1, wherein a holder made of metal or hard synthetic resin is mounted on a side of the intake manifold body where the intake port is connected to the intake port. 3. An annular protrusion formed integrally with an elastic member at an opening end of a side of the intake manifold main body that is connected to the intake port, and an annular groove is provided around the intake port. Two
An intake manifold for the V-type two-cylinder engine described.