JPS62210254A - Air intake device for engine - Google Patents

Abstract

PURPOSE:To secure the side space of an engine in an engine room reasonably, by making the expansion of the independent intake pipes, which are expanded to the side of the engine body, smaller as they come to one end of the cylinder arranging direction. CONSTITUTION:A surge tank 10 is furnished at the upper side of an engine body 1, sloped along the bonnet line BL, and the dead space between the bonnet line BL and the surge tank 10 is utilized effectively. Independent intake pipes 9 expanded to the side of the engine body 1 are expanded, positioning closer to a side 1a of the engine body 1 at the independent intake pipe 9-4 which is at the rearmost side in the cylinder arranging direction. Therefore, the engine side-space in the engine room can be secured reasonably.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an intake system for an engine, and more particularly to an improvement in an intake system equipped with a surge tank that defines an intake expansion chamber in an intake passage. .

(Prior art) Recently, in the intake system of engines, especially automobile engines, a surge tank is arranged in the engine's intake system in order to improve the filling efficiency due to the dynamic effect of intake air. There is one in which these are connected by separate intake pipes.

This type of intake system uses a long independent intake pipe to improve filling efficiency, especially in the low load range.
Generally, the surge tank is placed above the engine body, and the independent intake pipe is curved to bulge out to the side of the engine. This allows for smooth intake air flow, which eliminates the problem of intake resistance, and reduces the size of the device. (See Utility Model Application Publication No. 175666/1983).

(Problem to be Solved by the Invention) However, this type of intake system has a problem in that the space on the side of the engine in the limited engine room is occupied by the independent intake pipe that bulges in either direction of the engine. are doing.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an intake system for an engine that minimizes the occupation ratio of an independent intake pipe in a space to the side of the engine without increasing intake resistance.

(Means and effects for solving the problem) The present invention focuses on the arrangement relationship between a surge tank and an independent intake pipe, and provides one longitudinal end of a surge tank that is arranged above the engine body and extends in the cylinder arrangement direction. An independent intake pipe, which extends away from one side of the surge tank and then curves toward one side of the engine body, is located at one end in the cylinder arrangement direction. The independent intake pipe is located close to one side of the engine body.

With this configuration, the length and bend of the independent intake pipes connected to each cylinder are the same as before, but the proportion of the space occupied by the independent intake pipes in the side space of the engine can be reduced toward one end of the engine. can do.

(Example) In Figs. 1 to 3, l is an engine main body, and the engine main body 1 is an in-line four-cylinder type and is installed vertically in the engine room A, that is, the cylinder arrangement direction is directed toward the longitudinal direction of the vehicle body. It is listed. This engine body 1 is composed of a cylinder block 2, a cylinder head 3, a cylinder head cover 4, etc., and each cylinder 5 of the engine body has two air intakes, a first and a second intake formed in the cylinder head 3. The boats 6.7 are opened and each intake boat 6.7 has a
An intake valve (not shown) is provided in each case.

The first and second intake boats 6.7 are formed to be branched within the cylinder head 3, and the convex end thereof is a common intake boat 8, which is connected to one side 3a of the cylinder head 3, that is, the engine. It is opened on one side 1a of the main body 1.

The intake passage connected to the common intake boat 8 includes, in order from the intake board 8 side, an individual independent intake pipe 9, a surge tank 10 defining an intake expansion chamber, a throttle body 11, a common intake pipe 12, and an air cleaner (not shown). It consists of
Each of the independent intake pipes 9 is provided with a fuel injection valve 13 at its connecting end to the cylinder radiator 3.

The surge tank 10 is arranged above the engine body 1, and has the minimum volume necessary to obtain the intake dynamic effect.
Its vertical cross section is formed equally over the longitudinal direction. The surge tank 10 is arranged so that its longitudinal direction is in the cylinder arrangement direction, and the surge tank 10
The surge tank 10 is inclined so that the rear end 10a is higher than the front end 10b (see FIG. 2), and the inclination angle θ of the surge tank 10 is approximately equal to the inclination angle of the bonnet lines B and L.

On one side 10c of the surge tank 10, upstream independent intake pipe sections 14 that extend independently are arranged in parallel in the cylinder arrangement direction. The branch pipes L5a of the intake manifold 15 are connected to the downstream end of the upstream independent intake pipe portion 14, and each branch pipe 14a is , t! to the intake boat 8 which opens on one side 3a of the cylinder head 3, respectively. ! It is controlled.

That is, the upstream independent intake pipe portion 14 integrally formed in the surge tank 10 and each branch pipe 15a of the intake manifold 15 constitute the independent intake pipe 9 that connects the surge tank 10 and the intake boat 8. , the independent intake pipe 9 extends away from one side 10c of the surge tank 10, and then
It has a curved shape that extends downward and finally toward one side 3a of the cylinder head 3. The independent intake pipes 9-1 are arranged in order from the front end in the air arrangement direction.
9-2.9-3.9-4 are considered to be the same pipe length,
One side 1 of the engine body l toward the independent intake pipe 9 located on the rear end side in the cylinder arrangement direction, that is, towards the independent intake pipe 9-4.
It is arranged to pass through a position close to a. In FIG. 3, reference numeral 16 is a mask back attached to the dash panel 17.

In the above configuration, the surge tank 10 is arranged to be inclined along the bonnet lines B and L, and the independent intake pipe 9-4 located at the rear end in the cylinder arrangement direction is closer to one side 1a of the engine body l. Because they are located close together,
The lengths of all the independent intake pipes 9-1 to 9-4 can be made equal without any difficulty.

Further, the occupation ratio in the engine room A of the independent intake pipe 9 that bulges out toward one side la of the engine body 1 can be made smaller as it goes toward the independent intake pipe 9-4. In other words, by tilting the surge tank 10, the dead space sandwiched between the bonnet line BL and the surge tank 10 is effectively utilized, and the bulge of the independent intake pipe 9 can be made smaller toward the rear end of the engine body 1. As a result, it is possible to easily secure the space to the side of the engine.

(Effects of the Invention) As is clear from the above description, according to the present invention, the bulge of the independent intake pipe that bulges to the side of the engine body can be reduced in the cylinder arrangement direction without causing problems such as an increase in intake resistance. Since it can be made smaller toward one end, it is possible to easily secure a space on the side of the engine in the carrot room.

[Brief explanation of drawings]

Figure 1 is a partial front view of the engine body viewed from the front, Figure 2 is a side view of the engine body viewed from the other side, and Figure 3 is a plan view of the inside of the engine room viewed from above. 1: Engine body 1a One side of engine body 3 Niji cylinder head 5: 4A cylinder 8: Common intake boat 9: Independent intake pipe lO: Surge tank 10a: Rear end of surge tank 10b: Front end of surge tank 10c Knee side B, I: Bonnet line A: Engine room Figure 2 Date Figure 3

Claims (1)

[Claims] (1) A surge tank arranged above the multi-cylinder engine body and extending in the direction of the cylinder arrangement and the intake port of each cylinder are connected by independent intake pipes arranged in parallel in the direction of the cylinder arrangement, and the independent intake pipes are arranged in the direction of the cylinder arrangement. In an engine intake device having a shape that extends away from one side of the surge tank and then curves toward one side of the engine body, the surge tank is inclined so that one end thereof is higher than the other end. An intake system for an engine, wherein the independent intake pipe is located closer to one side of the engine main body as the independent intake pipe is located closer to one end in the cylinder arrangement direction.