JPH0447127A - Intake/exhaust device of engine with exhaust turbo supercharger - Google Patents

Abstract

PURPOSE:To decrease the driving force of a compressor and improve the supercharging response by providing an exhausted turbo supercharger with a scroll means which preliminarily rotates intake air to the same rotational direction with the compressor, at the up stream of the compressor. CONSTITUTION:An exhaust turbo supercharger 7 arranged at an engine body 1 is formed of a compressor 8, a turbine 9 and the like. In the compressor 8, an intake introduction passage 8d opened at the central part of a compressor impeller 8b is formed on a compressor housing 8a. A scroll passage 8c for discharging pressurized air formed in a scroll shape at the outer circumference of the compressor impeller 8b is provided. At the part just upstream of the compressor 8 of the intake passage 12 connected to the intake introduction passage 8d, a scroll means 14 at which intake air is preliminarily rotated to the same rotational direction with the compressor is set. The scroll means 14 is formed by providing a scroll passage 16 formed in a scroll shape while it is communicated with a connection passage 15, on the outer circumference part of the connection passage 15.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an intake and exhaust system for an exhaust turbo supercharged engine.

(Conventional technology) Conventionally, in engines equipped with exhaust turbo superchargers,
It is preferable to introduce intake air into the supercharger by connecting the upstream intake passage to the compressor in a straight line to reduce passage resistance, but due to various constraints when installing the engine in a vehicle, it is preferable to connect the upstream intake passage to the compressor in a straight line as shown above. It is difficult to introduce natural intake air. The same applies to the extraction of exhaust gas from the supercharger (see, for example, Japanese Utility Model Application No. 88831/1983).

That is, the main body of the exhaust turbo supercharger is connected to an exhaust manifold that collects exhaust ports in relation to the exhaust ports of the engine, and is installed on the exhaust side so as to introduce exhaust gas immediately after exhaust.

On the other hand, in the intake device, an upstream member such as an air cleaner is disposed above the engine, and an intake passage bends downward from the upper portion and is further bent and connected to the shaft of the supercharger. Moreover, it is common in small passenger cars and the like that the exhaust gas discharged from the turbine in the axial direction is bent from below to the rear by the exhaust passage.

(Problem to be Solved by the Invention) However, if the passage on the intake side or exhaust side of the exhaust turbocharger is bent near the connection to the turbocharger as described above, the problem occurs at this part. There is a problem in that the flow of intake air or exhaust gas is obstructed, increasing ventilation resistance, making it impossible to obtain sufficient supercharging performance, and making it impossible to achieve the desired engine output performance.

In other words, an increase in intake resistance on the intake side increases the driving energy of the compressor to obtain the same amount of intake air, and there is also a loss of momentum when the compressor rotates a basically linear flow. There is a problem in that the turbine efficiency decreases, and the rotation increase at the start of supercharging is delayed, resulting in a decrease in supercharging response, and particularly in the low rotation region, supercharging performance deteriorates. On the other hand, an increase in passage resistance on the exhaust side causes an increase in exhaust pressure, leading to a decrease in high-speed fuel efficiency and output performance.

SUMMARY OF THE INVENTION In view of the above circumstances, the present invention aims to provide an intake and exhaust system for an engine with an exhaust turbo supercharger, which reduces ventilation resistance in the intake and exhaust to the exhaust turbo supercharger and increases turbine efficiency. This is the purpose.

(Means for Solving the Problems) In order to achieve the above object, an engine intake/exhaust system of the present invention supercharges intake air by a compressor connected via a turbine shaft to a turbine rotated by energy of exhaust gas. This is constructed by providing a turning means immediately upstream of the compressor for pre-rotating the intake air in the same direction as the compressor rotation direction.

Alternatively, a rotating means for changing the flow of exhaust gas in the same direction as the turbine rotation direction is provided immediately downstream of the turbine.

(Function) In the intake/exhaust system for an exhaust turbo supercharged engine as described above, the driving force of the compressor is increased by pre-rotating the intake air in the same direction as the compressor rotation direction using a turning means provided immediately upstream of the compressor. This results in a higher turbine rotation in the light load range and a faster rise in turbine rotation during acceleration. In addition, at full load, the turbocharging work increases by the amount of pre-rotation given to the intake at low speeds and fully open, and at high speeds and fully open, the exhaust pressure decreases and the charging amount increases due to the reduction in required turbocharging work. This is intended to improve output characteristics.

On the other hand, by changing the flow of exhaust gas in the same direction as the turbine rotation direction using the swirling means provided immediately downstream of the turbine of the exhaust turbo supercharger, the swirling speed component of the exhaust gas flow downstream of the turbine can be utilized. , speed energy is derived without changing to temperature by promoting the discharge of exhaust gas, suppressing temperature rise, and making full use of the output increase from the exhaust turbo supercharger without causing a rise in exhaust pressure. That's what I do.

(Example) Hereinafter, each embodiment of the present invention will be described along with the drawings.

Embodiment 1 FIG. 1 is a schematic front view of an exhaust turbo supercharged engine equipped with an intake and exhaust system of this embodiment, and FIGS. 2 to 4 each show a schematic configuration of the intake and exhaust system.

In the engine body 1, a cylinder head 3 is fastened to the upper part of a cylinder block 2, and a head cover 4 is disposed at the upper part, and an oil pan 5 is disposed at the bottom. An exhaust manifold 6 is attached to the side of the cylinder head 3 to lead out exhaust gas from an exhaust port (not shown).
This exhaust manifold 6 collects exhaust gas from each cylinder and discharges it from a connecting portion 6a at the lower center.

An exhaust turbo supercharger 7 is disposed on the exhaust side of the engine body 1, and the exhaust turbo supercharger 7 is composed of a compressor 8, a turbine 9, and a center housing 10. ing. A turbine wheel 9b housed inside a turbine housing 9a of the turbine 9 and a compressor impeller 8b housed inside a compressor housing 8a of the compressor 8 are connected by a turbine shaft 11 and rotate together. . The above turbine shaft 1
1 is supported by a center housing 10, and the turbine housing 9a and compressor housing 8a are connected to both sides of the center housing 10.

The turbine housing 9a of the turbine 9 includes:
A scroll passage 9c for introducing exhaust gas formed in a spiral shape is provided on the outer periphery of the turbine wheel 9b, and a scroll passage 9c for introducing exhaust gas is provided from the center of the turbine wheel 9b toward the outside in the axial direction of the turbine shaft 11. A discharge passage 9d is provided. The upstream end of the scroll passage 9c opens upward, is connected to the downstream end of the exhaust manifold 6, and is formed so that the passage cross-sectional area gradually decreases from its inlet to the outer periphery of the turbine wheel 9b. The turbine wheel 9b is rotationally driven by the energy of the exhaust gas.

On the other hand, the compressor housing 8a of the compressor 8 is formed with an intake air introduction passage 8d that opens from the center of the compressor impeller 8b toward the outside in the axial direction of the turbine shaft 11. A scroll passage 8c formed in a spiral shape for discharging pressurized air is provided. The scroll passage 8C has a passage cross-sectional area that gradually increases from the upstream part on the center side to the downstream side, and opens to the discharge port 8e at the downstream end. The discharge port 8e at the downstream end is connected to an intake manifold that communicates with an intake port on the opposite side of the exhaust manifold 6 of the cylinder head 3 via an intercooler (not shown) or the like.

The intake passage 12 on the upstream side is connected to the intake air introduction passage 8d of the compressor 8, and a turning means for pre-rotating the intake air in the same direction as the compressor rotation direction is provided immediately upstream of the compressor 8. 14 have been installed. In this example, the turning means 14 is formed in a spiral shape on the outer periphery of a connecting passage 15 extending in a direction perpendicular to the turbine shaft 11 and connected to the compressor housing 8a, and communicating with the connecting passage 15. The turning passage 16 is formed such that the passage cross-sectional area gradually decreases from the upstream side to the downstream side along the rotation direction of the compressor impeller 8b. The upstream end of the swirl passage 16 extends upward in the tangential direction, and the downstream end of the upstream intake passage 12 is connected to the connection opening 16a, and the upstream intake passage 2 is bent in the lateral direction. and is connected to the air cleaner 13.

The intake air flowing into the swirling passage 16 by the intake-side swirling means 14 flows from the outer peripheral side to the center side while being given a pre-rotation along the swirling passage 16, and flows into the connecting passage with a swirling flow. 15 to the intake introduction passage 8d of the compressor 8, the air is pressurized by the D rotation of the compressor impeller 8b along the swirling flow, and is discharged from the scroll passage 8c.

On the other hand, the exhaust gas discharge passage 9d of the turbine 9 on the exhaust side is connected to the exhaust passage [8] on the downstream side, or the exhaust gas is directly downstream of the turbine 9 in the same direction as the turbine rotation direction. Swirling means 19 are provided for changing the flow. In this example, one of the turning means extends in a direction perpendicular to the turbine shaft 11 and extends into the turbine housing 9.
A swirling passage 21 formed in a spiral shape and communicating with the connecting passage 20 is provided on the outer periphery of the connecting passage 20 connected to the turbine wheel 9b. The passage is formed so that the cross-sectional area of the passage gradually increases from the upstream side to the downstream side. Further, the downstream end 21a of the swirl passage 21 extends downward in the tangential direction, and the upstream end of the downstream exhaust passage 18 is connected to the connection opening thereof, and the downstream exhaust passage 18 is bent in the lateral direction. and connected to a catalyst (not shown).

By the exhaust-side swirling means 19, the exhaust gas flows from the turbine 9 into the connecting passage 20 while rotating as the turbine wheel 9b rotates, and then flows from the center side into the outer circumference side swirling passage 21. The flow direction is changed in the swirling direction along the swirling passage 21 and is quickly discharged to the downstream exhaust passage 18.

To explain the effect of the swirling means 14 on the intake side, the swirling radii of the inlet and outlet of the compressor 8 are respectively r.
l+r2, the tangential components of the intake flow velocity are respectively Ul and U
2 and the mass flow rate is M, the torque T of the compressor 8 is obtained from the conservation of angular momentum as follows: T=MshaU2 ・r2 MllUl' rrB
-A, which is the value obtained by subtracting the fresh air angular momentum A at the compressor inlet from the angular momentum B of the supercharged air at the compressor outlet.

Therefore, in the light load range, considering the same operating conditions, a large intake flow velocity U1 is given in advance by the swirling passage 16 of the swirling means 14, but in the case without the swirling means, U
, is small because it is induced for the first time when the compressor 8 rotates. That is, the value of A increases due to the turning means 14, while B remains constant under the same operating conditions, and since the exhaust gas energy PS is also constant with the same charging amount, the compressor torque T becomes a small value. .

Then, when the compressor rotation is ω, PS-TX
Since there is a relationship of ω, when the exhaust gas energy PS is constant, the compressor rotation ω increases by an amount equivalent to the reduction rate of the compressor torque T, and the supercharging response improves.

In addition, regarding torque improvement at full load, in the low rotation range before intercept, the above-mentioned A-B+T, so the larger the B value, the more the supercharging air energy A value increases, resulting in an increase in supercharging pressure. Become. On the other hand, in the high rotation region after intercept, in T-AB, when the boost pressure is constant and A is constant, the larger the B value, the lower the required compressor work, which is due to the reduction in the required exhaust gas energy. This results in a decrease in exhaust pressure.

Embodiment 2 A configuration diagram of this embodiment is shown in FIG. 5, which is a modification of the intake side turning means.

The rotation means 24 on the intake side in this example is formed in a spiral shape on the inner peripheral surface of the intake passage 12 extending in the axial direction immediately upstream of the intake introduction passage 8d of the compressor 8 of the exhaust turbo supercharger 7. A swirling flow generation guide 25 is provided to pre-rotate the intake air in the same direction as the compressor rotation direction.

Embodiment 3 This example is shown in FIG. 6, and is an example in which pre-rotation is applied to the intake air only in a low intake air amount region.

Immediately upstream of the compressor 8 of the exhaust turbo supercharger 7, a swirling means 14 is provided with a swirling passage 16 similar to that in the first embodiment, and a direct intake passage 12a is provided through the center of the swirling passage 16. In addition, a control valve 26 for opening and closing the direct intake passage 12a is provided in the direct intake passage 12a.
is interposed. Furthermore, the upstream end of the upstream introduction passage 27 of the swirling passage 16 of the swirling means 14 is connected to the control valve 2.
6 is formed so as to merge with the direct intake passage 12a and communicate with the upstream intake passage 12.

Then, as shown in FIG. 7, the control valve 26 closes in the low intake air amount region I of low load and low rotation to block the direct intake passage 12a, and the turning passage 16 of the turning means 14
In the high-load, high-speed, high-intake-air-amount region (2), the control valve 26 is opened and intake air is also supplied from the direct intake passage 12a.

According to this example, in the low intake air amount region 1, the supercharging response is improved by pre-rotating the intake air, and in the high intake air amount region 2, the ventilation resistance is reduced from the direct intake passage 12a to supply a large amount of intake air. This is what we do.

Embodiment 4 This embodiment is shown in FIG. 8, and its basic structure is to give pre-rotation to the intake air by a guide similar to that of Embodiment 2, and the strength of the pre-rotation is variable.

The swirling means 29 on the intake side in this example has a swirling flow generation guide 30 formed in a spiral shape on the inner peripheral surface of the intake passage 12 extending in the axial direction immediately upstream of the compressor 8. The swirling flow generation guide 30 of the swirling means 29 pre-rotates the intake air in the same direction as the rotating direction, and
The angle α is configured as a variable means 31 that can be adjusted.

Then, the angle α of the guide 30 by the variable means 31 is increased in the low intake air amount region I to give a strong pre-rotation to the intake air, while the angle α of the guide 30 is decreased in the high intake air amount region ■ to give the intake air a strong pre-rotation. The ventilation resistance is reduced without giving any pre-rotation.

Embodiment 5 This example is shown in FIG. 9, and is an example in which different swirling flows are generated by a plurality of swirling means.

Immediately upstream of the compressor 8 of the exhaust turbo supercharger 7, there is a first pre-rotating passage for pre-rotating the intake air in the same direction as the rotational direction of the compressor of the exhaust turbo supercharger 7 through a swirl passage 16 similar to that in the first embodiment. A pivot means 14 is provided and concentrically adjacent to the pivot passage 16 of the first pivot means 14;
A second swirling means 33 that provides a weak swirling flow in the opposite direction is disposed, and the center portions of both are communicated, and an injector 35 is disposed at the center of the swirling passage 34 of the second swirling means 33. It is.

The second swirling means 33 is constituted by a swirling passage 34 having a spiral shape in the opposite direction, and is connected to the upstream intake passage 12 similarly to the first swirling means 14 . The main swirling flow of intake air is obtained by the first swirling means 14,
The intake air is pre-rotated and introduced in the same direction as the compressor rotation direction of the exhaust turbo supercharger 7, thereby improving the supercharging response in the low intake air amount range and increasing the torque in the high intake air amount range. be.

In addition to the swirling flow caused by the first swirling means 14, the fuel injected from the injector 35 is transferred to a portion where the intake air flow is turbulent due to the swirling flow in the opposite direction caused by the second swirling means 33. The fuel is atomized and promotes vaporization and atomization of the injected fuel to improve combustibility.

Example 6 This example is shown in FIG. 10 and is another example in which different swirling flows are generated by a plurality of swirling means.

Immediately upstream of the compressor 8 of the exhaust turbo supercharger 7, there is a first swirling means for pre-rotating the intake air in the same direction as the rotational direction of the compressor of the exhaust turbo supercharger 7 through a spiral-shaped swirl passage 16 similar to the previous example. 14, and a second swirling means 37 that provides a weak swirling flow in the same direction is arranged concentrically and adjacent to the swirling passage 16 of the first swirling means 14,
The center portions of the two are communicated with each other, and the second rotating means 3
The injector 35 is disposed at the center of the turning passage 38 of No. 7.

Further, a control valve 39 is interposed in the intake air introduction portion of the second swirling means 37, and the control valve 39 opens in the low intake air amount region I in the low rotation and low load region, and opens in the low intake air amount region I in the high rotation and high load region. Opening/closing is controlled to close the air volume area.

The second swirling means 37 is composed of a swirling passage 38 having a small diameter spiral shape in the same direction, and the swirling flow of fresh intake air is obtained by the first swirling means 14, and the exhaust turbo supercharger 7
The intake air is pre-rotated and introduced in the same direction as the compressor rotation direction, improving supercharging response in low intake air volume ranges and increasing torque in high intake air volume ranges.

On the other hand, the swirling flow of intake air by both swirling means 14.37 has different speeds and causes turbulence, and the fuel injected from the injector 35 in the area where the control valve 39 is open is atomized and injected. It promotes fuel vaporization and atomization to improve combustibility, and in the high intake air volume range, the intake air is supplied without turbulence (with little ventilation resistance).

Embodiment 7 This embodiment is shown in FIG. 11 and is an example of a combination of an intake relief passage and a turning means.

Immediately upstream of the compressor 8 of the exhaust turbo supercharger 7, a swirl means 14 is provided for pre-rotating the intake air in the same direction as the rotation direction of the compressor of the exhaust turbo supercharger 7 using a spiral-shaped swirl passage 16. The intake passage 12 on the upstream side passes through the center of the passage 16 and is connected thereto. Also,
Relief passage 4 branches from supercharging passage 41 downstream of compressor 8 and communicates with intake passage 12 upstream of compressor 8
2 is formed, and the other end of this relief passage 42 is connected to the intake air introduction part 16a of the swirling passage 16 of the swirling means]4, and the relief air is pre-rotated to the upstream side of the compressor 8 via the swirling means 14. Supplied in condition.

A relief control valve 43 is interposed in the relief passage 42, and the relief control valve 43 is controlled to open in a low intake air amount region I of a low rotation and low load region, as shown in FIG. This relief air is introduced in a pre-rotated state in the same direction as the rotational direction of the compressor 8 by the turning means 14, and an effect of increasing the compressor rotation speed is obtained. Furthermore, in the high intake air amount region (3), the relief control valve 43 is closed, and air is taken in with reduced ventilation resistance.

Embodiment 8 This embodiment is shown in FIG. 13 and is another example of the combination of the intake relief passage and the turning means.

Directly upstream of the compressor 8 of the exhaust turbo supercharger 7, a swirling means 14 is provided for pre-rotating the intake air in the same direction as the rotation direction of the compressor of the exhaust turbo supercharger 7 using a spiral-shaped swirl passage 16. The intake passage 12 on the upstream side is connected to the intake passage 16, and intake air is supplied thereto. Also, a supercharging passage 41 downstream of the compressor 8 and a turning passage 16 of the turning means 14 are provided.
Relief passage 4 communicating with intake passage 12 on the more upstream side
2 is formed, and a relief control valve 43 that is controlled to open and close in the same manner as in the previous example is interposed in this relief passage 42, and the entire amount of relief air and intake air is pre-rotated by the turning means 14 in the same direction as the rotation direction of the compressor 8. In this case, the compressor rotation speed is increased.

Embodiment 9 This embodiment is shown in FIG. 14 and is yet another example of a combination of an intake relief passage and a turning means.

A first system for pre-rotating the intake air in the same direction as the rotational direction of the compressor of the exhaust turbo supercharger 7 using a spiral-shaped turning passage 16 immediately upstream of the compressor 8 of the exhaust turbo supercharger 7.
A rotating means 14 is provided, and the first rotating means 14
A second swirling means 46 that provides a swirling flow in the same direction is disposed concentrically adjacent to the swirling passage 16, and the center portions of the two are communicated with each other.

Introduction section 16a of the turning passage 16 of the first turning means 14
A relief passage 42 in which a relief control valve 43 is interposed is connected to the intake passage 12 , and the intake passage 12 on the upstream side is connected to a rotation passage 47 of the second rotation means 46 .

In this example, the rotating means of the previous example is separated into one for the relief passage 42 and one for the intake passage 12, and the same effect can be obtained, and the compressor rotational speed during relief is increased.

Embodiment 10 This embodiment is shown in FIG. 15 and is an example in which the angular momentum of the pre-rotation provided by the intake-side turning means is variable.

Directly upstream of the compressor 8 of the exhaust turbo supercharger 7, a swirl means 14 is provided by a spiral-shaped swirl passage 16, and the nozzle width of the nozzle portion 48 to the compressor 8 is changed in the center of the swirl passage 16. Variable means 49 is interposed.

In this variable means 49, a disk-shaped adjustment member 50 with a protruding center portion 50a moves forward and backward according to the operating state by an actuator (not shown), and changes the nozzle width at the outlet of the turning passage 16, thereby controlling the compressor 8. The device is configured to change the angular momentum of the pre-rotation of the incoming intake air.

That is, in order to increase the angular momentum of the pre-rotation by the swirling passage 16 of the swirling means 14, it is effective to increase the flow velocity of the nozzle portion 48;
The adjustment member 50 of the variable means 49 is operated such that the effective area of the airflow is reduced in a low intake air amount region, while it is expanded in a high intake air amount region to reduce ventilation resistance.

This improves the reduction in charging amount due to increased ventilation resistance in high-speed, high-load ranges and the decrease in turbocharging response improvement effect due to insufficient pre-rotation in low-speed, low-rpm ranges, ensuring optimal angular momentum in each range. That's what I do.

Embodiment 11 This example is shown in FIG. 16 and is another example in which the angular momentum of the pre-rotation imparted by the intake-side turning means is variable.

Immediately upstream of the compressor 8 of the exhaust turbo supercharger 7, there is a swirling means 14 formed by a swirling passage 16 similar to the other side.
At the same time, variable means 52 for changing the passage cross-sectional area A of the suction portion 16a of the swirling passage 16 is interposed.

This variable means 52 tilts a rectifying plate-shaped adjustment member 53 according to the operating state by an actuator (not shown) to change the passage cross-sectional area A of the suction part 16a, thereby changing the pre-rotation angle of the intake air introduced into the compressor 8. Configured to change momentum.

That is, in order to increase the angular momentum of the pre-rotation by the turning passage 16 of the turning means 14, it is effective to increase the flow velocity of the suction part 16a.
The adjusting member 53 of the variable means 52 is operated so that the cross-sectional area A is reduced in a low intake air amount region, while expanded in a high intake air amount region to reduce ventilation resistance. This ensures the optimum angular momentum in each region, as in the previous example.

In addition, when reducing the cross-sectional area A of the suction part 16a, by operating the adjustment member 53 of the variable means 52 to reduce the passage area A from the inside to the outside, it is possible to maintain the same flow rate with the same passage area A. Also, it is preferable that the turning radius R is larger, since the momentum is also larger.

Embodiment 12 This embodiment is shown in FIG. 17 and is yet another example in which the angular momentum of the pre-rotation imparted by the intake side turning means is variable.

A swirl means 55 is provided immediately upstream of the compressor 8 of the exhaust turbo supercharger 7, and a variable means 57 for switching the passage area of the suction portion 56a of the swirl passage 56 is interposed. .

This variable means 57 divides the turning passage 56 into two passages by a partition wall 58, and an on-off valve 59 is interposed in the inflow portion of one passage, and this on-off valve 59 is tilted according to the operating state by an actuator (not shown). The angular momentum of the pre-rotation of the intake air introduced into the compressor 8 is changed by changing the passage cross-sectional area of the suction portion 56a.

That is, as in the previous example, in order to increase the angular momentum of the pre-rotation by the swirling passage 56 of the swirling means 55, the on-off valve 59 is used to reduce the cross-sectional area of the suction portion 56a in a low intake air amount region in order to increase the flow velocity of the suction portion 56a. On the other hand, in a high intake air amount region, the variable means 57 is controlled to open the on-off valve 59 to enlarge the cross-sectional area and reduce ventilation resistance. This ensures the optimum angular momentum in each region, as in the previous example.

Embodiment 13 This example is shown in FIG. 18 and is yet another example in which the angular momentum of the pre-rotation imparted by the intake side turning means is variable.

Immediately upstream of the compressor 8 of the exhaust turbo supercharger 7, a first turning means 61 is provided by a first turning passage 62 having a spiral shape, and adjacent thereto, a second turning means 61 is provided by a second turning passage 64 having a small turning radius. A rotating means 63 is provided, and a first on-off valve 65 and a second on-off valve 66 are interposed in the respective suction portions 62a and 64a. Further, the nozzle width of the nozzle portion 62b of the first swirling passage 62 is small, and the nozzle width of the nozzle portion 64b of the second swirling passage 64 is formed larger than this. The above structure constitutes a variable means 67 that changes the passage area and radius of the suction portion of the swirling passage 16 as a whole, and the nozzle width.

The first on-off valve 65 of the variable means 67 is controlled to open in a low intake air amount range and close in a high intake air amount area, and the second on-off valve 66 closes in a low intake air amount area and closes in a high intake air amount area. The operation is controlled so that it opens in the air volume range, and overall, in the low intake air volume range, the suction passage area is reduced, the turning radius is increased, and the nozzle width is narrowed, while in the high intake air volume range, the suction passage is opened. The area is increased, the turning radius is decreased, and the nozzle width is increased to ensure optimal angular momentum in each area and to reduce ventilation resistance.

Embodiment 14 This embodiment is shown in FIG. 19, and is an example in which a throttle valve is installed upstream of the swirling means on the intake side.

A swirl means 14 with a spiral-shaped swirl passage 16 is provided immediately upstream of the compressor 8 of the exhaust turbo supercharging a17, and an upstream throttle valve 69 is provided in the intake passage 12 on the upstream side connected to the suction portion 16a of the swirl passage 16. is interposed.

In the case in which the upstream throttle valve 69 is disposed as described above, unlike in the case in which the throttle valve is disposed only downstream of the compressor 8, the turning passage 16 of the turning means 14 is in a negative pressure state, so that the flow flows into the compressor 8. The rotation speed of the pre-rotation of the intake air is increased. That is, the turning means 1
4, when the angular momentum of the pre-rotation given to the intake air is the same, the lower the air density, the higher the turning speed.

As shown in FIG. 20, an upstream throttle valve 69 is provided in the intake passage 12 on the upstream side of the turning passage 16 of the turning means 14.
The supercharging passage 4 on the downstream side of the compressor 8
1 is equipped with a main throttle valve 70, the intake air amount is adjusted by the main throttle valve 70, and the upstream throttle valve 69 closes only in a low intake air amount region to reduce the negative pressure acting on the compressor 8 and provide lubrication. It may be configured to suppress oil from flowing out to the intake side.

Furthermore, an upstream throttle valve 69 similar to that described above is interposed in the intake passage 12 upstream of the adjusting member 53 of the variable means 52 of the eleventh embodiment (FIG. 16), or
An upstream throttle valve 69 similar to that described above is provided in the entire intake passage 12 on the upstream side of the on-off valve 59 of the variable means 57 (FIG. 17).
The rotation speed may be increased by interposing the suction portion 56a of the rotation means 55 in combination with means 57 for varying the cross-sectional area of the suction portion 56a.

Embodiment 15 This example is shown in FIG. 21 and is a structural example for increasing the swirling flow of the swirling means on the intake side.

For the swirling means 14 by the spiral-shaped swirling passage 16 provided immediately upstream of the compressor 8 of the exhaust turbo supercharger 7, the flow is rectified along the swirling flow toward the center at the end face of the nozzle portion 16a of the swirling passage 16. A portion 72 is provided. This rectifying portion 72 is configured in the shape of a groove or a protrusion. The rectifying section 72 strengthens the pre-rotation swirl flow imparted to the intake air in the swirl passage 16.

The angle at which the rectifying section 72 is formed is made variable depending on the operating conditions. In the low intake air amount region, the angle is made small in the tangential direction to further increase the swirling flow, and in the compressor 8, the angle is made small in the tangential direction to reduce ventilation resistance. The angle may be changed significantly in the direction.

In addition, a spiral rectifying portion for strengthening the swirling flow is formed on the end face of the adjusting member 50 of the variable means 49 of the tenth embodiment (FIG. 15) toward the central protrusion 50a, thereby adjusting the nozzle width. The turning speed may be increased in combination with a change in .

Embodiment 16 This embodiment is shown in FIG. 22 and is a modification of the exhaust side turning means.

For a turning means 19 formed by a spiral-shaped turning passage 21 provided immediately downstream of the turbine 9 of the exhaust turbo supercharger 7, a protrusion 73 conically protruding toward the turbine 9 is provided at the center of the turning passage 21. It was formed.

The protrusion 73 allows the exhaust gas discharged from the turbine 9 with a swirling flow to smoothly flow into the swirling passage 21 of the swirling means 19.

(Effects of the Invention) According to the present invention as described above, for an exhaust turbo supercharger, a turning means for pre-rotating intake air in the same direction as the compressor rotation direction is provided immediately upstream of the compressor, or a turning means is provided immediately downstream of the turbine. By installing a turning means to change the flow of exhaust gas in the same direction as the turbine rotation direction, it is possible to reduce the driving force of the compressor, improve supercharging response, and increase torque. Exhaust turbo supercharger 7
This makes it possible to secure the desired output increase.

[Brief explanation of drawings]

1 is a schematic front view of an exhaust turbo supercharged engine equipped with an intake and exhaust system according to a first embodiment of the present invention; FIG. 2 is a front configuration diagram of the intake and exhaust system shown in FIG. 1; FIG. 4 is a side view of the intake side turning means, FIG. 4 is a side view of the exhaust side turning means, and FIGS. 5 and 6 show the intake and exhaust systems in the second and third embodiments. FIG. 7 is a characteristic diagram showing the switching area of the third embodiment; FIG.
11 are main part configuration diagrams showing the intake and exhaust devices in the fourth to seventh embodiments, FIG. 12 is a characteristic diagram showing the switching region of the seventh embodiment, and FIGS. 13 to 11 are FIG. 19 is a main part configuration diagram showing the intake and exhaust devices in the eighth to fourteenth embodiments, FIG. 20 is a main part configuration diagram showing a modification of the fourteenth embodiment, and FIGS. 21 to 22 The figures show the 15th to 16th embodiments.
FIG. 2 is a main part configuration diagram showing an air intake and exhaust system in an embodiment of the present invention. 1...Engine body, 6...Exhaust manifold, 7...Exhaust turbo supercharger, 8...
...Compressor, 8a...Compressor housing, 8b...Compressor impeller,
8C...Scroll passage, 9...Turbine, 9a...Turbine housing, 9b...
... Turbine wheel, 9C ... Scroll passage, 10 ... Center housing, 11 ...
... Turbine shaft, 12 ... Upstream intake passage, 14, 24° 29.33, 37.46, 55, 6
1.63... Intake side turning means, 16, 34, 3
8.47,56゜62.64...Swivel passage, 1
8... Exhaust passage, 19... Exhaust side turning means, 21... Turning passage, 31°49.52,
57.67...Variable means. fig fig fig fig fig fig fig fig fig fig fig fig fig fig fig fig fig fig fig fig fig fig fig fig.

Claims (5)

[Claims] (1) In an exhaust turbo supercharged engine in which intake air is supercharged by a compressor connected via a turbine shaft to a turbine rotated by the energy of exhaust gas, there is a An intake/exhaust device for an engine with an exhaust turbo supercharger, characterized in that it is provided with a turning means for pre-rotating intake air in the same direction. (2) The intake and exhaust system for an exhaust turbo supercharged engine according to claim 1, wherein the turning means is formed in a spiral shape, and the intake passage is connected to the turbine shaft from a direction perpendicular to the turbine shaft. (3) Claim 1 or 2 further comprising variable means for changing the strength of pre-rotation of intake air by the swirling means.
The intake and exhaust system for the exhaust turbo supercharged engine described above. (4) In an engine with an exhaust turbo supercharger, in which intake air is supercharged by a compressor connected via a turbine shaft to a turbine that is rotated by the energy of exhaust gas, there is a space immediately downstream of the turbine in the same direction as the turbine rotation direction. An intake/exhaust device for an exhaust turbo-type engine with a supercharger, characterized in that it is provided with a turning means for changing the flow of exhaust gas in one direction. (5) The intake and exhaust system for an exhaust turbo supercharged engine according to claim 4, wherein the turning means is formed in a spiral shape, and the exhaust passage is connected to the turbine shaft from a direction perpendicular to the turbine shaft.