JPH02248619A - Intake device of v-type engine with supercharger - Google Patents

Abstract

PURPOSE:To establish the tuning point of a resonance effect or an inertial effect in an intake system to the higher speed side of an engine by providing a communication passage which communicates directly with a double intake aggregation between the intake aggregations of right and left banks. CONSTITUTION:A mechanical supercharger 5 is installed between right and left V-shaped banks, and independent intake passages 23a, 23b of respective cylinders are extensively-provided to intake aggregates 41a, 41b for respective left and right banks through between an engine body and a mechanical supercharger 5. The downstream side of right and left intake aggregates 21a, 21b are connected with each other through a communication passage 42. Since this permits the tuning point of a resonance effect or inertial effect in an intake system to correct its movement toward lower speed side, it is possible to improve charging efficiency in the high speed range of the engine.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an intake system for a supercharged V-type engine in which a mechanical supercharger is mounted between left and right banks.

(Prior art) When installing a mechanical supercharger on a ■ type engine, the idea of arranging the supercharger in the space between the banks in order to effectively utilize the space between the banks has been proposed, for example. 1986-
It has been known from the past as described in Japanese Utility Model Publication No. 5330 and Japanese Utility Model Application Publication No. 611624.

By the way, when a mechanical supercharger is arranged between the V banks in this way, the intake passages of the cylinders of the left and right banks are gathered below the mechanical supercharger, as described in the above-mentioned publications. If you connect it to the discharge port of a mechanical supercharger,
Because it would be difficult to arrange the intercooler, etc., and the flow resistance of the intake passage would also increase, an independent intake passage for each cylinder was extended between the engine body and the mechanical supercharger, and separate intake passages were installed for each left and right bank. It has been considered that the intake air collecting section is configured to communicate with the air intake collecting section. In this case, the independent intake passages for each cylinder are extended between the engine body and the mechanical supercharger within the V bank, which inevitably makes the intake passages longer and narrower, causing resonance in the intake system. The tuning point of the effect or inertial effect must be closer to the low rotation range.

However, in engines equipped with mechanical superchargers,
Mechanical superchargers themselves have the characteristic of being able to obtain high supercharging efficiency in low engine speed ranges, so in high engine speed ranges, it is better to use the resonance or inertia of the intake system to increase the supercharging effect. There is a demand.

In that case, if the tuning point of the resonance effect or inertial effect is shifted toward the low rotation side as described above, a problem arises in that the intake air filling efficiency cannot be sufficiently increased on the high engine rotation side.

(Object of the Invention) The present invention has been made in view of the above problems, and includes a mechanical supercharger mounted between the left and right banks, and an independent intake passage of each cylinder connected to the engine body and the mechanical supercharger. The purpose of this invention is to improve the charging efficiency in the high-speed range by setting the tuning point of the resonance effect or inertial effect of the intake system closer to the engine's high speed in a V-type engine that extends through the gap.

(Structure of the Invention) By providing a communication passage that directly communicates the intake passages of the left and right banks, the present invention provides a tuning point of the intake system on the high engine rotation side without causing any inconvenience in supercharging by a mechanical supercharger. It focuses on the fact that it is possible to obtain , and its structure is as shown below. That is, the intake system for a supercharged V-type engine according to the present invention has a mechanical supercharger mounted between the left and right banks formed in a V-shape, and a connection between the engine body and the Moeki mechanical supercharger. In a supercharged V-type engine in which an independent intake passage of each cylinder is extended to the intake collecting parts of each of the left and right banks through a gap between the intake passages of each cylinder, the intake collecting parts of the left and right banks are directly connected to each other. This is characterized by the provision of a communication path that shifts the tuning point of the resonance effect or inertia effect of the intake system to the higher engine speed side.

In the intake system configured as described above, the intercooler can be disposed in front of the engine, having cooling sections corresponding to the intake air gathering sections for each left and right bank.

(Function) The mechanical supercharger operates efficiently in the low engine speed range, thereby providing a sufficient supercharging effect in the low speed range. In addition, by directly communicating the intake collecting parts of the left and right banks through the communication passage, a tuning point for the resonance effect or inertial effect of the intake system can be obtained in the engine high speed range, thereby improving the charging efficiency in the high speed range. will improve.

In addition, the mechanical supercharger is mounted between the left and right banks, and the independent intake passage for each cylinder extends between the engine body and the mechanical supercharger, creating a compact intake system with low intake resistance. can get.

Further, by disposing an intercooler having a cooling section corresponding to the intake air collecting section for each left and right bank in front of the engine, an intake system with good distribution and low intake resistance can be obtained.

(Example) Examples will be described below based on the drawings.

FIG. 1 schematically shows a system for mechanical supercharging of an engine according to an embodiment of the present invention.

In this system, a mechanical supercharger 5 is disposed in an intake passage 4 that communicates an intake hood 2 of the engine 1 with an air cleaner 3. This mechanical supercharger 5 is based on the so-called Lysholm type screw compressor, which combines a male rotor with four leaves and a female rotor with six grooves. is connected to an air-cooled intercooler 6. Also, throttle valve 7
is provided upstream of the supercharger 5, and a bypass passage 8 that communicates the downstream of the throttle valve 7 with the downstream of the intercooler 6 and bypasses the supercharger 5 is formed.

An auxiliary throttle valve 9 is provided at a position immediately downstream of the junction point of the bypass passage 8 of the intake passage 4 . The auxiliary throttle valve 9 is connected to a throttle valve lever 12 via an auxiliary throttle valve lever 10 and a grooved rod 11. When the throttle valve 7 opens to a predetermined opening degree, the auxiliary throttle valve 9 begins to open. Further, the bypass passage 8 is provided with a pressure-responsive bypass valve 13 . In the non-supercharging region, this bypass valve 13 is opened and natural intake without passing through the supercharger 5 is performed.

The supercharger 5 is connected via an electromagnetic clutch 14 and a centrifugally variable drive pulley 15 to a driven pulley 26, which will be described later, which is a variable pulley on the driving side.

A fuel injector 16 is also provided in the intake passage 4 in the vicinity of the intake boat 2, and an air flow meter 17 is provided downstream of the air cleaner 3.

The electromagnetic clutch 14 is cut in the low rotation/low load range shown by the solid line in FIG. 2, and is turned on in other ranges. Further, the bypass valve 13 is opened and closed at a load line (for example, -20011IIHg) shown by a broken line in the figure.

The driving pulley 15 and the driving-side variable pulley combined therewith are basically known as centrifugal pulleys, and their combination allows the engine to rotate at an excessive speed relative to the engine speed, as shown in FIG. A characteristic is obtained in which the charger rotational speed gradually saturates at high rotational speeds, that is, the supercharging pressure does not rise too much in the high engine rotational speed range.

In the low rotation/low load region of the engine, the electromagnetic clutch 14 is cut and supercharging is stopped, and in other regions, while ensuring sufficient intake air volume on the low rotation side, the boost pressure is reduced on the high rotation side. Control is carried out to prevent excessive rise. Furthermore, the amount of air entering the supercharger 5 itself is adjusted by the aforementioned auxiliary throttle valve 9, thereby controlling the supercharging pressure relative to the load. Therefore, this electromagnetic clutch 14. By combining the variable pulley 15 and the auxiliary throttle valve 9, it is possible to efficiently stop or suppress supercharging in a low load range and to control supercharging according to the engine speed and load in other operating ranges. In a low load range, the bypass valve 13 is opened by the intake negative pressure, and natural intake is performed via the bypass passage 8.

FIG. 4 is a front view of the V-type engine according to this embodiment, and FIG.
The figure is a plan view of the same. This engine 1 is a V type 6 cylinder, and the three cylinders of each of the left and right banks 18a and 18b are arranged offset from each other by a predetermined amount in the longitudinal direction of the engine,
In a space 19 between the left and right banks 18a and 18b, a mechanical supercharger 5 is arranged in the longitudinal direction of the engine with its male and female rotors aligned vertically.

Intake boat 22L of left and right banks 18a and 18b.

2b is located inside each bank 18a, 18b, rises upward between the mechanical supercharger 5, and connects connecting pipes 20a, 2
Branch pipe section 22a of intake manifold pipes 21a and 21b via 0b
, 22b.

The intake manifold pipes 21a, 21b extend in the longitudinal direction of the engine in the left and right upper portions between the banks, and their respective branch pipe portions 22a, 22b, together with the connecting pipes 20a, 20b, connect the left and right banks 18a,
Independent intake passages 23a, 23b corresponding to each cylinder 18b
It consists of And these independent intake passages 23a,
23b, a fuel injector 16 is disposed near the engine-side attachment ends of the connecting pipes 20a, 20b toward the intake boats 2a, 2b.

The supercharger 5 includes left and right connecting pipes 20a, 20b and injectors 16, 16 below the intake manifold pipes 21a, 21b.
located between the left and right banks 18a, 18b from the top.
The mounting arm 2 extends between the independent intake passages 23a and 23b of the
It is supported and fixed to the engine l side by 4a and 24b. Further, the center of the bottom of the supercharger 5 is connected to the engine l side by a tubular pin 25 that also serves as a passage for lubricating oil. A drive pulley 15 is connected to the front end of the supercharger 5 via an electromagnetic clutch 14, and a large diameter portion of a driven pulley 26 provided on the left side of the front side of the engine 1 is connected to the drive pulley 15. , a belt 28 is provided between the small diameter portion of the driven pulley 26 and the crank pulley 27, respectively.
．． 29 is installed. Note that the crank pulley 27 also includes a drive pulley 30 for an air conditioner. As shown in FIG. 4, a belt 34 is stretched between a power steering drive pulley 31 and an alternator drive pulley 32 via an idler 33.

The supercharger 5 has an inlet part 35 at the rear end, and this inlet part 3
5 is connected to an intake pipe 36 connected to the air cleaner 3. A throttle body 37 is interposed in the middle of this intake pipe 36. Moreover, the supercharger 5 is
It has a discharge port 38 extending upward from the casing side wall on the right bank 18b side. This discharge port 38 is
Above the casing of the supercharger 5, it is connected to a discharge pipe 40 that constitutes a discharge passage 39.

An intercooler 6 is disposed in front of the engine 1 at right angles to the vehicle traveling direction. The intercooler 6 has cooling parts 6λ, 6a for each left and right bank 18a, 18b, and these are arranged substantially symmetrically with respect to the engine center. The intake port 6b is located near the engine center, and discharge ports 6c are provided at both left and right ends.

The discharge pipe 40 of the supercharger 5 is connected to the suction port 6b of the intercooler 6. In addition, the left and right intake manifolds 21a, 21b have both banks 18r on the upstream side of their inlet manifold parts 41λ, 41b constituting the surge tank.
It is connected to pipe portions 6d, 6d extending from the discharge ports 6c, 6c of the intercooler 6 extending left and right on the top of the intercooler 18b.

The downstream sides of the left and right intake manifold pipes 21a and 21b are connected to each other by a communication passage 42. As a result, the tuning point of the resonance of the intake system is shifted to the engine high speed side, and the charging efficiency in the high speed range is improved.

Note that this communication path 42 is compactly formed so as to cross the space above the supercharger 5. Also, this communication path 4
2 is provided with a bypass passage 8 that bypasses the supercharger 5 and intercooler 6 and connects the intake pipe 36 on the upstream side. In the low engine load range, the passage 8
A pressure-responsive bypass valve 13 that opens is provided.

(Effects of the Invention) Since the present invention is configured as described above, a mechanical supercharger is mounted between the left and right banks, and the independent intake passage of each cylinder is passed between the engine body and the mechanical supercharger. In the extended V-type engine, it is possible to correct the fact that the tuning point of the resonance effect or inertial effect of the intake system is closer to the low rotation side, and improve the charging efficiency in the engine high rotation region.

In addition, by installing an intercooler in front of the engine that has a cooling section that corresponds to the intake air gathering section for each left and right bank, in addition to improving the filling efficiency in the high rotation range as mentioned above, it also improves distribution. However, the effect of reducing the intake resistance can also be obtained.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram of an engine supercharging system according to an embodiment of the present invention, Figs. 2 and 3 are control characteristic diagrams of the embodiment, and Fig. 4 is a schematic front view showing the overall structure of the embodiment. Figure, 5th
The figure is a plan view of the same. l: Engine, 5: Mechanical supercharger, 6: Intercooler, 18a: Left bank, 18b: Right bank, 23a, 23
b: Independent intake passage, 41a, 41b: Intake gathering portion, 4
2: Communication path. Agent Patent Attorney Jun Susumu Fuji −

Claims (2)

[Claims] (1) A mechanical supercharger is installed between the left and right banks formed in a V shape, and the independent intake passages of each cylinder are connected to the intake passages for each of the left and right banks by passing between the engine body and the mechanical supercharger. In a V-type engine with a supercharger that extends to the
A communication path is provided between the intake collecting parts of the left and right banks, which directly communicates both the intake collecting parts, thereby displacing the tuning point of the resonance effect or inertial effect of the intake system to the engine high speed side. Intake system for V-type engine with feeder. (2) The intake system for a V-type engine with a supercharger according to claim 1, further comprising an intercooler having a cooling section corresponding to the intake air collecting section of each left and right bank in front of the engine.