JPH0727375Y2 - Engine intake system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to an intake device for an engine, and in particular, an intake manifold is provided for each bank in a V-type engine, and intake air is introduced into the intake manifold. The present invention relates to an intake device including a high-speed intake passage and a low-speed intake passage as an intake passage.

(Prior Art) Conventionally, as disclosed in, for example, Japanese Unexamined Patent Publication No. 62-210219, a low speed intake passage and a high speed intake passage are used as an intake passage for introducing intake air into an intake collecting portion where independent intake passages of a predetermined cylinder are collected. There are those provided with an intake passage for use.

Applying such an intake system to a generally known V-type engine, and arranging both intake collecting parts above one of the banks in a biased manner in consideration of the routing of the intake passage on the upstream side of the intake collecting part. Can be considered.

In that case, the intake collecting portion for the cylinder on the other side is located above the independent intake passage of the bank on the one side because of the requirement that the lengths of the independent intake passages be equal.

Therefore, for such an intake layout, providing only two intake passages for low speed and high speed in the intake collecting portion makes the height and width of the engine wider, which makes mounting in the engine room difficult. Further, if the layout is restricted by limiting the height and width, the bending rate of the intake passage increases, the intake resistance increases, and the output decreases.

(Object of the Invention) The present invention has been made in view of the above problems. Even if a V-type engine is provided with a low-speed intake passage and a high-speed intake passage as in the prior art, output reduction due to intake resistance does not occur. The purpose is to make a compact intake layout.

(Construction of the device) The characteristic feature of the construction is that both intake collecting portions are biased to the upper side of one bank, and the intake collecting portion on the other bank side is located above the independent intake passage on the one bank side. By opening a high-speed intake passage at one end of both intake manifolds in the axial direction of the engine, the high-speed intake passage communicates smoothly with the intake manifold, reducing the intake resistance at high speeds, while reducing the intake air on the bank side. By opening the low speed intake passage on the lower surface of the collecting portion, it is possible to reduce the bend of the independent intake passage on the one bank side without increasing the engine height and width, and to reduce the bending of the intake collecting portion of the other bank. The height of the engine can be suppressed by opening the low speed intake passage on the side surface.

(Example) Hereinafter, an example of the present invention will be specifically described.

As shown in FIG. 2, the six-cylinder horizontal V-type engine CE, which is ignited in the order of the first to sixth cylinders # 1 to # 6, has the first, third, and fifth cylinders # in which the ignition order is not continuous. 1, # 3, # 5 are arranged in the front side bank F as viewed in the front-rear direction of the vehicle, while the second, fourth, sixth cylinders # 2, # 4, # in which the ignition order is not continuous
6 is arranged in the rear bank R.

Then, for example, the first cylinder # 1 sucks intake air into the combustion chamber 4 from the independent intake passage 3 via the intake port 2 when the intake valve 1 is opened, and the intake air is pistoned (not shown).
Compress with, ignite and burn with a spark plug (not shown),
When the exhaust valve 5 is opened, the combustion gas is exhausted to the independent exhaust passage 7 through the exhaust port 6, and the independent intake passage 3 is inhaled slightly upstream of the intake port 2. A fuel injection valve 8 for injecting fuel is disposed with its injection port inclined toward the downstream side. Then, fuel is supplied to the fuel injection valve 8 through a fuel supply passage 9. Further, the combustion chamber 4 has a blow-by gas passage.
Blow-by gas is introduced through 10 (see FIG. 1). The second to sixth cylinders # 2 to # 6 have the same configuration.

The engine CE is designed so that the axes of both banks F and R are oriented in the vehicle width direction inside the engine room ER below the bonnet BN that is formed with a gentle slope that becomes higher toward the rear side of the vehicle. Are arranged (so-called horizontal placement). The throttle body 14 is provided between the upper end of the cylinder head S of the rear bank R and the hood BN.
An intake manifold IM connected to the common intake passage 11 (see FIG. 1) via (see FIG. 1) is arranged. Since the bonnet BN is considerably high above the rear bank R, and the space above the cylinder head S is secured with a relatively large margin in the vertical direction, the intake manifold IM is arranged without interfering with the bonnet BN. be able to. The intake manifold IM is composed of a manifold main body M and an independent intake passage portion N. The manifold main body M has a surge tank (intake intake set) for stabilizing intake air supply, as will be described in detail below. Part), as a resonance passage for effectively producing a resonance effect at medium and low speeds, and as a volume part for effectively producing an inertia effect at high speeds. Further, the independent intake passage portions N are respectively provided in the manifold main body portion M and the intake ports 2 of the cylinders # 1 to # 6.
It is composed of six independent intake passages 3 that connect with each other.

The manifold body M includes a front side high speed intake passage 21 extending in the vehicle width direction, a front side low speed intake passage 25 arranged along a rear side surface thereof, and a front side high speed intake passage 21. Rear side high-speed intake passage 22 that extends in the vehicle width direction at a slightly lower position on the rear side in parallel with it
And the rear side low-speed intake passage arranged along the lower surface of the
26 and are provided. (In this embodiment, the front-side and rear-side high-speed intake passages form the intake collecting portion and the high-speed intake passage, which are the structural requirements of the present invention.)
The downstream end of the front high-speed intake passage 21 and the downstream end of the rear high-speed intake passage 22 communicate with each other through a communication passage 33.
(See FIG. 1) are connected in a loop shape, and these three intake passages 21, 22, 33 form a substantially U-shaped intake passage (see FIG. 1). , A communication passage opening / closing valve 37 that opens / closes according to the operating state of the engine CE (see FIG. 1)
Is provided. In addition, the front side low speed intake passage 25
Is connected to the front high-speed intake passage 21 from the side (see FIG. 27 of FIG. 1), and the rear low-speed intake passage 26 has a downstream end below the rear high-speed intake passage 26. (See Fig. 28). The upstream side ends of the front side and rear side high speed intake passages 21 and 22 are opened to the flange portion 18, while the front side and rear side low speed intake passages 25 and 2 are provided.
The upstream side of 6 is also open to the flange portion 18 (see FIG. 1).

On the other hand, the upstream ends of the independent intake passages 3 of the front side cylinders # 1, # 3, # 5 are connected to the front side surface of the front side high speed intake passage 21. After extending in a substantially linear manner while gradually descending in the direction, the curve is bent so as to be oriented substantially vertically downward, and is connected to the intake port 2 of the corresponding cylinder of the front side bank F. In addition, the independent intake passage 3 of the rear side cylinders # 2, # 4, # 6
Is connected to the front side surface of the rear high-speed intake passage 22, from which the independent intake passages 3 extend substantially horizontally in the front direction, and in the downstream portion extend substantially downward, It is connected to the corresponding intake port 2 of the side bank R.

Hereinafter, the configuration of each part of the intake device will be described in more detail.

As shown in FIG. 1, in order to effectively utilize the space above the engine CE, the common intake passage 11 is formed in a shape that is slightly flat in the vertical direction and has a cross section that is formed into a substantially rectangular shape that is horizontally long. In the branch portion 12, the resonance effect is obtained by utilizing the phenomenon that the intake pulsation of the intake system on the front side bank F side and the intake pulsation of the intake system on the rear side bank R side cause an almost equalizing state due to the interference action. Inversion part of pressure wave when using (open end)
Are provided to form the. Immediately downstream of the collecting portion 17, the intake system includes a front high-speed intake passage 21, a rear high-speed intake passage 22, as described later in detail.
Front low speed intake passage 25 and rear low speed intake passage
It is branched to 26 and. In this case, the front-side and rear-side high-speed intake passages 21 and 22 are opened in the longitudinal direction of the collecting portion 17 having a horizontally long rectangular cross section, and the upper front-side low-speed intake passage 25 of the collecting portion 17 is opened. A rear low speed intake passage 26 is opened below the collecting portion 17 (see FIG. 2). The front and rear high-speed intake passages 21,22
The passage sectional area of is set to be sufficiently larger than the passage sectional areas of the front and rear low speed intake passages 25 and 26 so that a large amount of air can be supplied at high speed. Then, the downstream end of the front low speed intake passage 25 is connected to the front connecting portion 27.
Is connected to the front side high speed intake passage 21 from the side, while the downstream side end of the rear side low speed intake passage 26 is connected to the rear high speed intake passage 22 from below by the rear side connection portion 28. There is. Therefore, at a low speed, the intake air in the low speed intake passages 25, 26 once flows into the high speed intake passages 21, 22, is dispersed here, and then supplied from each independent intake passage 3 to the corresponding cylinder. That is, the high speed intake passages 21 and 22 function as a kind of surge tank at low speed.

On the front side surface of the front side high speed intake passage 21, the first, third and fifth cylinders # belonging to the front side bank F are
1, # 3, # 5 independent intake passages 3, 3, 3 are connected to each other, while the front side surface of the rear high-speed intake passage 22 includes second, fourth, and sixth cylinders belonging to the rear bank R. 2, # 4, # 6 independent intake passages 3, 3, 3 are connected.

Immediately downstream of the collecting portion 17, front side and rear side high speed intake passages 21 and 22 are provided with front side and rear side high speed intake passage open / close valves 31 and 32, respectively. . As will be described later, these front side and rear side high speed intake passage opening / closing valves 31 and 32 are closed when the number of revolutions is equal to or lower than a predetermined value in the engine revolution range where the resonance effect should be utilized. Has become.

FIG. 3 is an elevation view of the intake manifold IM seen from the flange portion 18 side toward the downstream side.

As shown in FIG. 3, the upstream end portions of the front and rear high speed intake passages 21 and 22 and the upstream end portions of the front and rear low speed intake passages 25 and 26 are relatively large. By welding to the single highly rigid flange portion 18, the front side and rear side low speed intake passages 25, 26 are
The rear high speed intake passages 21, 22 are integrally mounted so as to be located above and below the high speed intake passages 21, 22. Therefore, in the vicinity of the flange portion 18, the front side and rear side low speed intake passages 25, 26 and the front side, rear side high speed intake passages 21, 22 are increased in rigidity by the flange 18.
Further, the front side / rear side high speed intake passages 21 and 22 and the front side / rear side low speed intake passages 25 and 26 independently have a relatively small vertical rigidity, but in the present invention, they are arranged in the vertical direction. In this part, the thickness of the intake system in the vertical direction is increased and the rigidity thereof is increased. As a result, it is possible to effectively prevent the vibration of the intake system caused by the inertia of the throttle body 14.

By the way, front and rear low speed intake passages 25, 26
Is formed to have a relatively small diameter in order to increase the substantial intake passage length related to the propagation of the pressure wave, so that the intake resistance increases and the normal intake air flow deteriorates.

Further, since the front and rear throttle valves 13f and 13r are arranged on the left and right in the same direction as the front and rear high speed intake passages 21 and 22 are arranged, the front and rear high speed intake passages are arranged. The intake distribution to 21,22 is equalized.

As shown in FIG. 1, on the downstream side from the collecting portion 17, the front side high speed intake passage 21 and the rear side high speed intake passage 22 are
Independent intake air that extends from the front side high speed intake passage 21 to the downstream side and the second cylinder # 2 that gradually expands to the left and right, extends downstream, and is connected to the independent intake passage 3 that extends from the first cylinder # 1. Rear high-speed intake passage to which passage 3 is connected
The region extending from 22 extends to the downstream side in parallel with each other. And the part where these extend in parallel to each other (hereinafter,
In this portion, which is referred to as a parallel portion, the front high-speed intake passage 21 is arranged at a position slightly higher than the rear high-speed intake passage 22 (see FIG. 3). Further, on the downstream side from the low speed intake passage branch portion 24, the front low speed intake passage 25 and the rear low speed intake passage 26 gradually expand in the left-right direction and extend toward the downstream side. In the section, the front low-speed intake passage 25 is integrally formed by sharing the flat rear side wall of the front high-speed intake passage 21, while the rear low-speed intake passage 26 is formed in the rear high-speed intake passage. 22 flat lower walls are shared and are integrally formed.

As shown in FIG. 3, in the parallel portion, the front side,
The passage cross-sectional areas of the rear-side low-speed intake passages 25 and 26 are set to be considerably smaller than the passage cross-sectional areas of the front-side and rear-side high-speed intake passages 21 and 22. Thus, as will be described later in detail, regarding the propagation of the pressure wave, the substantial intake path lengths of the front and rear low speed intake passages 25 and 26 are substantially equal to those of the front and rear high speed intake passages 21 and 22. It becomes longer than the target intake path length.

Further, the front side high speed intake passage 21 is arranged at a position such that the lower surface thereof is substantially the same height as the upper surface of the rear high speed intake passage 22. As described above, the front low-speed intake passage 25 is the front high-speed intake passage.
By sharing the rear side wall of 21 and integrally forming it with the rear side wall, the vertical height of the engine can be suppressed by the thickness of one intake passage.

On the other hand, the rear-side low-speed intake passage 26 shares the lower wall of the rear-side high-speed intake passage and is formed integrally therewith, so that they have a very compact shape with a suppressed height. Has become.

As a result, the space a can be opened closer to the lower end mounting portion of the windshield, and even if this engine moves to the rear side in the event of a vehicle collision, the space a causes the engine to be mounted on the windshield. It is difficult to hit the glass and damage to the glass can be reduced.

Further, since the rear high-speed intake passage 22 can be located higher, the bending of the independent intake passage 3 on the rear side can be reduced, the intake resistance can be reduced, and the variation in the output between the front side and the rear side can be further reduced.

Further, if the rear side low speed intake passage 26 is naturally positioned on the side surface of the rear high speed intake passage 22, the engine width in the rear side direction will be widened.

Further, as shown in FIG. 2, the front side high speed intake passage
21 is the second, the fourth, which extends from the rear side so as to intersect with this.
Since the sixth intake cylinder # 2, # 4, # 6 is integrally formed by sharing the upper wall of each independent intake passage 3,3,3, the intake system is more compact and the rigidity is improved. Has been.

By the way, as shown in FIG. 1 again, the downstream end of the front high-speed intake passage 21 and the downstream end of the rear high-speed intake passage 22 are connected by a substantially U-shaped communication passage 33. ing. Then, in the vicinity of the connection portion with the rear-side high-speed intake passage 22, they are connected by a communication passage 33. And
A communication passage opening / closing valve 37 that opens and closes the communication passage 33 is provided in the communication passage 33 near the connection portion with the rear-side high-speed intake passage 22. As will be described later, the communication passage opening / closing valve 37 is opened to form a volume portion (pressure reversal portion) when utilizing the inertial effect in a predetermined high rotation range.

Hereinafter, the pressure wave supercharging performed in the above configuration will be described with reference to FIG.

In a predetermined high speed range where the inertia effect should be used, the communication passage opening / closing valve
37 and the front and rear high-speed intake passage opening / closing valves 31 and 32 are both opened. At this time, the front-side and rear-side high-speed intake passages 21 and 22 communicate with each other through a communication passage 33, which integrally form a volume portion having a considerably large volume, and this volume portion is a pressure wave inversion portion. Acts as. Then, in each of the cylinders # 1 to # 6, when the intake valve 1 is opened, the negative pressure generated in the intake port 2 serves as a vibration source to form a standing wave having the independent intake passage 3 as a resonance system. The intake air is pushed into the combustion chamber 4 by the positive pressure of the steady source, and the charging efficiency is increased (inertial effect).

On the other hand, in the medium / low speed range where the resonance effect should be utilized, at the time of a predetermined high speed, the communication passage opening / closing valve 37 is closed, while the front and rear high speed intake passage opening / closing valves 31, 32 are opened. Then, for example, the first and the first belonging to the front bank F
Regarding the third and fifth cylinders # 1, # 3, and # 5, the negative pressure generated when the intake valve 1 is opened is in order of the independent intake passage 3 and the front side high-speed intake passage 21 whose upstream end is open. The resonance system is excited to generate a standing wave, and supercharging is performed by the positive pressure of the standing wave. Each cylinder # belonging to the rear bank R
The pressure wave supercharging due to the resonance effect is similarly performed for 2, # 4 and # 6.

Further, in the middle / low speed range where the resonance effect should be used, at a predetermined low speed, both the communication passage opening / closing valve 37 and the front and rear high speed intake passage opening / closing valves 31, 32 are closed. At this time, since the front and rear high speed intake passages 21 and 22 are closed on the upstream side, for example, the front bank F
For each of the cylinders # 1, # 3, # 5 on the side, the pressure wave is sequentially generated by the independent intake passage 3, the front high-speed intake passage 21, and the front low-speed intake passage 25 having the upstream end opened. The formed resonance system is vibrated to generate a lower frequency standing wave, and supercharging is performed by the positive pressure of the standing wave. For this reason,
Even at such a low speed, the resonance effect can be effectively enhanced, and the filling efficiency can be improved.

As described above, according to the present invention, while effectively increasing the filling efficiency by effectively utilizing the inertial effect and the resonance effect over a wide rotation range, the vibration of the intake device is effectively prevented, and the intake flow characteristics of the low speed intake passage are improved. Can be improved.

(Effect of the Invention) As described above, according to the present invention, even if the intake collecting portion is arranged on one bank side of the V-type engine, the curvature of the intake passage is minimized to reduce the intake resistance. After planning
The intake system can be laid out compactly.

[Brief description of drawings]

FIG. 1 is a plan view of an intake system for a 6-cylinder horizontal V-type engine showing an embodiment of the present invention. FIG. 2 is an elevational view of an engine equipped with the intake device shown in FIG. FIG. 3 is an elevational view of the intake manifold shown in FIG. 1 seen from the flange side. FIG. 4 is a cross-sectional view taken along the line DD of the intake system shown in FIG. FIG. 5 is a diagram showing the positional relationship between the front and rear high-speed intake passages, the front and rear low-speed intake passages, and the independent intake passages in the parallel portion of the intake device shown in FIG. . CE: 6-cylinder horizontal V-engine, F: front bank, R: rear bank, IM: intake manifold,
M: Manifold main body, N: Independent intake passage, BN
...... Bonnet, # 1 to # 6 ... First to sixth cylinders, 1 ...
... intake valve, 2 ... intake port, 3 ... independent intake passage, 11
...... Shared intake passage, 11f, 11r ...... Front side, rear side branch intake passage, 12 …… Branch part, 14 …… Throttle body,
17 …… Collecting part, 18 …… Flange part, 21 …… Front side high speed intake passage, 22 …… Rear side high speed intake passage, 25 …… Front side low speed intake passage, 26 …… Rear side low speed intake Passage, 31 …… Front side high speed intake passage open / close valve, 32 …… Rear side high speed intake passage open / close valve, 33 …… Communication passage, 37 …… Communication passage open / close valve.

Claims (1)

[Scope of utility model registration request] 1. An intake system for a V-type engine, comprising: an independent intake passage communicating with each cylinder; and two intake collecting portions for collecting the independent intake passages for each bank. The intake collecting section is biased to the upper side of one bank, and the intake collecting section of the other bank is located above the independent intake passage communicating with the cylinder of the one bank, and intake air is sucked into both intake collecting sections at least at low speed. The low-speed intake passage to be introduced is communicated with the high-speed intake passage for introducing intake air at least at high speed, and the high-speed intake passage is opened at one end of both intake collecting portions in the engine axial direction, and the intake collecting portion of the one-side bank is connected. A low speed intake passage communicating with the intake manifold is opened at the lower surface of the intake collecting portion, and a low speed intake passage communicating with the intake collecting portion of the other bank is opened at the side surface of the intake collecting portion. An intake device for an engine to be.