JP7376384B2 - Internal combustion engine with exhaust turbocharger - Google Patents

Description

The present invention relates to an internal combustion engine (multi-cylinder internal combustion engine) equipped with an exhaust turbocharger.

BACKGROUND ART In internal combustion engines for automobiles and the like, it is widely practiced to provide an exhaust turbo supercharger in order to improve output and the like. This exhaust turbo supercharger includes a turbine housing, a compressor housing, and a bearing housing, and the exhaust gas outlet passage of the turbine housing and the intake inlet of the compressor housing are oriented in opposite directions in the axial direction of the rotating shaft. It's open.

The cylinder head is formed with an exhaust port corresponding to each cylinder, and on the exhaust side of the cylinder head, either exhaust ports are opened individually corresponding to each cylinder, or there are a set of exhaust ports that communicate with each exhaust port. One exhaust outlet of the passage is open, and the exhaust turbocharger is generally fixed to the exhaust manifold if the exhaust outlets are individually open, or if the exhaust outlets are consolidated into one. is attached directly to the exhaust side of the cylinder head.

Now, an exhaust turbo supercharger is installed mainly to improve output, but if the exhaust turbo supercharger is placed on the side of the exhaust, the pressurized intake air may straddle the top of the cylinder head. Since the compressed air is sent to the intake side, there is a problem that the passage for the pressurized intake air becomes long and the responsiveness of acceleration and deceleration tends to be delayed.

Regarding this point, Patent Document 1 discloses that an exhaust manifold part and an intake manifold part are built into the cylinder head, and the collective passage of the exhaust manifold part and the collective passage of the intake manifold part are connected to one short side of the cylinder head. It is disclosed that the exhaust turbo supercharger is arranged and fixed such that the exhaust gas introduction passage of the turbine housing communicates with the exhaust gas collection passage and the intake mixture passage communicates with the intake outlet of the compressor housing. There is.

Japanese Patent Application Publication No. 2006-194227

In the configuration of Patent Document 1, the pressurized intake air directly enters the intake manifold portion, so it can be said that the responsiveness of acceleration and deceleration is extremely high, but there are also problems.

For example, since there is a considerable gap between the collective passage in the exhaust manifold section and the collective passage in the intake manifold section, the exhaust turbo supercharger must accommodate this by increasing the length of the bearing housing. , there is a problem that the exhaust turbo supercharger becomes larger than necessary.

Furthermore, the amount of intake air is controlled by a throttle valve, but if the compressor housing is attached directly to the cylinder head, it becomes a problem where to place the throttle valve. Furthermore, the intake system requires a surge tank to eliminate intake pulsation, but if the intake manifold is built into the cylinder head as in Patent Document 1, the surge tank cannot be placed, so the pulsation is directly transmitted to each cylinder. There is also the problem of putting it away.

Therefore, although the configuration of Patent Document 1 has excellent acceleration/deceleration responsiveness, there are many problems in applying it to an actual machine, and it must be said that it has low practicality.

The present invention has been made in view of the current situation, and while it is common to Patent Document 1 that the exhaust turbo supercharger is attached to one short side of the cylinder head, it will be provided in a highly practical manner. That is.

The internal combustion engine of the present invention is
``The exhaust turbo supercharger is placed on one short side of the cylinder head that is orthogonal to the intake side and exhaust side, and the turbine housing is located on the side of the exhaust side and the compressor housing is placed on the side of the intake side. It is arranged as follows.
This is the basic configuration.

In the above basic configuration,
"An exhaust gas collecting passage is open on one short side of the cylinder head, and the turbine housing of the exhaust turbo supercharger is fixed to one short side of the cylinder head while communicating with the exhaust gas collecting passage. and the compressor housing of the exhaust turbo supercharger is arranged with the intake outlet facing the cylinder head side ,
An intake manifold including an intercooler and through which intake air branches from the intercooler into branch passages is fixed to the intake side of the cylinder head , and the intake outlet of the compressor housing of the exhaust turbocharger is connected to the intake manifold . It is connected to the intercooler via a supercharging passage and a throttle valve that are arranged on the outside of the cylinder head so as to face the intercooler.
It has the following characteristics.

The intake manifold may be provided with a surge tank separate from the intercooler, or the intercooler may also be used as the surge tank. In any case, the throttle bubble will be located at the inlet of the intercooler.

In the present invention, since the exhaust turbo supercharger is attached to one short side of the cylinder head, the distance between the intake outlet of the compressor housing and the intake manifold can be made as short as possible, and the response of acceleration and deceleration can be improved. .

The intake outlet of the compressor housing and the intercooler are connected by a supercharging passage located outside the cylinder head, and since the intercooler and intake manifold are also externally attached to the cylinder head, the exhaust turbo Supercharged intake air can be supplied to the intake manifold by adjusting the length of the supercharging passage without increasing the size of the charger more than necessary. Also, the throttle bubble can be installed without any problems. Therefore, it is easy to apply to actual machines and has excellent practicality.

FIG. 2 is a partially schematic plan view of the embodiment. It is a II-II view of FIG. It is a III-III view of FIG. It is a top view of another example.

(1).Basic Structure Next, embodiments of the present invention will be described based on the drawings. This embodiment is applied to a three-cylinder internal combustion engine for automobiles. In the following, front and rear and left and right directions are used to specify the direction, but the front and rear direction is the direction of the crank axis, and the side where the timing chain is placed is the front, and the side where the transmission chain is placed is the back. . The left-right direction is a direction perpendicular to the crank axis and the cylinder bore axis.

FIG. 1 is a plan view showing the cylinder head 1 with the head cover omitted. In the cylinder head 1, an intake camshaft 2 and an exhaust camshaft 3, which show only the shaft center, are arranged in parallel. These are rotatably held by a cam cap (not shown). A sprocket 4 is attached to the front ends of the camshafts 2 and 3 via a VVT device (not shown), and the sprocket 4 and chain are covered with a front cover 5.

Further, the cylinder head 1 is formed with a plug hole 6 in which a spark plug, an ignition coil, etc. are arranged, and a group of valve holding holes 7. Although it goes without saying, a head cover (not shown) overlaps the cylinder head 1 and the front cover 5 from above.

One longitudinal side of the cylinder head 1 is an intake side 1a with an open intake port 8, and the other longitudinal side of the cylinder head 1 is an exhaust side 1b. Inside the cylinder head 1, a longitudinal longitudinal exhaust passage 9 with communicating exhaust ports is formed in close proximity to the exhaust side surface 1b, and the exhaust passage 9 opens on the rear surface 1c of the cylinder head 1. .

In the internal combustion engine of this embodiment, the crankshaft is arranged in a long position in the vehicle width direction, and the exhaust side surface 1b is arranged so as to face the forward direction of the vehicle. Therefore, it is a horizontal type with front exhaust and rear intake.

The front surface 1d and the rear surface 1c of the cylinder head 1 are shorter side surfaces, and the rear surface 1c is the shorter side surface as described in the claims, and the exhaust turbo supercharger 10 is attached to the rear surface 1c. . The exhaust turbo supercharger 10 includes a turbine housing 11 in which turbine blades (not shown) are rotatably arranged, a compressor housing 12 in which compressor blades (not shown) are rotatably held, and a compressor housing 12 in which a compressor blade (not shown) is rotatably held. and a bearing housing 13 located therein.

The exhaust turbo supercharger 10 is arranged in such a manner that the turbine housing 11 is located on the exhaust side surface 1b side, and the compressor housing 12 is located on the intake side surface 1a side. Therefore, the rotating shaft to which the turbine blades and compressor blades are fixed has a long posture in the left-right direction, and the exhaust gas outlet 14 of the turbine housing 11 is located on the side of the exhaust side surface 1b and is perpendicular to the exhaust side surface 1b. The intake inlet 15 on the rear surface 1c is located on the side of the intake side 1a and opens in a direction perpendicular to the intake side 1a .

As clearly shown in FIG. 3, the turbine housing 11 includes an inlet flange 17 in which the exhaust gas introduction passage 16 is opened, and the inlet flange 17 communicates the exhaust gas introduction passage 16 with the exhaust collection passage 9. It is fixed to the rear surface 1c of the cylinder head 1 with bolts. The exhaust gas outlet 14 of the turbine housing 11 opens into an outlet flange 18, and a catalyst case 19 is connected to the outlet flange 18 via a joint 19a. Needless to say, the catalyst case 19 has a built-in catalyst, and an exhaust pipe (not shown) is connected to the cone portion at the lower end.

In the compressor housing 12, intake air flows in the direction of the rotation axis of the compressor blades and is discharged in the direction tangential to the rotation of the compressor blades. Therefore, the intake outlet 20 opens toward the outer circumference of the compressor housing 12, but in this embodiment, the intake outlet 20 faces toward the cylinder head 1, as clearly shown in FIG. 1, for example. That is, the intake outlet 20 opens to the front side of the engine.

The exhaust turbo supercharger 10 of this embodiment is of a water-cooled type, and has a cooling water inlet port 21 at the lower part of the turbine housing 11 and a cooling water outlet port 22 at the upper end of the turbine housing 11. Note that the reference numeral 23 in FIG. 1 is an oil inlet, and the reference numeral 24 in FIG. 2 is an oil discharge port.

As can be inferred from FIG. 3, in this embodiment, the exhaust gas that has entered the exhaust gas introduction passage 16 flows upward to drive the turbine blades. Therefore, the turbine scroll chamber surrounding the turbine blades is located above the exhaust gas introduction passage 16. Therefore, the exhaust turbo supercharger 10 of this embodiment has an upper winding type.

A wastegate valve (not shown) for controlling boost pressure is built into the turbine housing 11, and the wastegate valve is driven by an actuator 26 shown in FIGS. 2 and 3. The actuator 26 is of a diaphragm type, and a rod 27 shown in FIG. 3 is connected to its valve body.The rod 27 moves forward and backward in its longitudinal direction and rotates a link 28, thereby adjusting the opening degree of the wastegate valve. can be adjusted.

(2).Relationship with the intake system As schematically shown in FIG. 1, an intake manifold 31 with an integrated intercooler 30 is fixed to the intake side surface 1a of the cylinder head 1. That is, the intake manifold 31 has branch passages 32 corresponding to each cylinder, and a flange 33 in which the branch passages 32 are formed is fixed to the intake side surface 1a.

The intercooler 30 is water-cooled (air-cooled may be used), and a water pipe 34 and a discharge pipe 35 are connected to each other. In this embodiment, the intercooler 30 also serves as a surge tank, and the intake air flowing into the intercooler 30 is branched from a branch passage 32 and sent to each cylinder.

A throttle body 37 that serves as an intake inlet is provided at a rear portion of the intercooler 30, and a throttle valve is built into this throttle body 37 , and the inlet of the throttle body 37 and the intake outlet 20 of the exhaust turbo supercharger 10 are connected to each other. are connected by a supercharging passage 38. The supercharging passage 38 is composed of a duct or a hose. Although the throttle body 37 is disposed on the rear upper surface of the intercooler 30, it can also be disposed on the rear surface of the intercooler 30.

The exhaust turbo supercharger 10 is arranged such that the intake outlet 20 is located near the intake side surface 1a of the cylinder head 1, while the throttle body 37 is arranged at the rear end of the intercooler 30 and opens rearward. (The rotation axis of the valve body in the throttle valve is oriented in the vertical direction perpendicular to the plane of the drawing in FIG. 1.) Therefore, the supercharging passage 38 has a generally crank-shaped configuration and is connected to the entrance of the throttle body 37.

As shown by the dashed line X1 in FIG . It is also possible to form the supercharging passage 38 in a straight line. Alternatively, as shown by the dotted line X2 in FIG. 1, the intake outlet 20 of the exhaust turbocharger 10 may be located directly behind the throttle body 37, and the supercharging passage 38 may be arranged in a straight line in a longitudinal longitudinal position. It is possible.

As shown by the dashed line in FIG. 3, the attitude of the supercharging passage 38 in side view (the attitude relative to the horizontal) can be set arbitrarily. Therefore, the height position of the end of the supercharging passage 38 can be adjusted in accordance with the height of the intercooler 30 and the height of the throttle body 37.

The internal combustion engine of this embodiment includes an EGR device. The EGR device includes an EGR pipe 39. The starting end of the EGR pipe 39 is connected to, for example, the lower cone portion of the catalyst case 19, and the terminal end of the EGR pipe 39 connects the air cleaner 40 and the exhaust turbo supercharger 10. It is connected to a midway portion of the intake passage 41. Furthermore, an EGR valve 42 is interposed in the middle of the EGR pipe 39.

In FIG. 1, the EGR pipe 39 and EGR valve 42 are depicted as being located behind the exhaust turbo supercharger 10, but this is for convenience in drawing; in reality, the EGR pipe 39 is It is placed close to the cylinder head 1. The EGR valve 42 may be fixed to the cylinder head 1. Although a water-cooled EGR cooler 43 is interposed in the EGR pipe 39, the EGR cooler 43 can also be placed below the exhaust turbo supercharger 10.

The present embodiment has the above configuration, and the exhaust turbo supercharger 10 is arranged on the rear surface of the cylinder head 1, and the intake outlet 20 of the exhaust turbo supercharger 10 is located near the intake side surface 1a of the cylinder head 1. Because of this position, the distance between the intake outlet 20 and the throttle body 37 (that is, the length of the supercharging passage 38) can be significantly reduced compared to when the exhaust turbo supercharger is connected to the exhaust side of the cylinder head. . Therefore, the responsiveness of acceleration/deceleration (or increase/decrease in torque) of the vehicle can be improved.

Furthermore, since the intake manifold 31 and the throttle body 37 are arranged outside the cylinder head 1, there is no space restriction when arranging the intake manifold 31 and the throttle body 37, which is highly practical.

Now, the exhaust gas purification performance standards for automobile internal combustion engines have become higher, and the catalyst case 19 has also become larger accordingly, but in the case of automobile internal combustion engines, the catalyst case Since there is a limit to how low the catalyst case 19 can be, it may be necessary to make the catalyst case 19 larger by increasing its height. In this regard, if the exhaust turbo supercharger 10 is of an upward winding type, it is possible to cope with an increase in the size of the catalyst case 19.

On the other hand, if the intercooler 30 is provided in the intake manifold 31 and the throttle body 37 is provided above it, the height of the throttle body 37 becomes considerably high. Therefore, by taking advantage of the fact that the exhaust turbo supercharger 10 is of the upper winding type and the intake outlet 20 is high, the height difference between the throttle body 37 and the intake outlet 20 is made as small as possible, and the supercharging passage 38 The layout can be simplified.

In the example shown in FIG. 4, the throttle body 37 is disposed on the rear surface of the intercooler 30, and its entrance opens toward the exhaust turbocharger 10. Therefore, the supercharging passage 38 is formed in a straight line, but in this embodiment, the length of the supercharging passage 38 is extremely short, so that the responsiveness of supercharging can be further improved.

Although the embodiments of the present invention have been described above, the present invention can be embodied in various other ways.

The present invention can be embodied in an internal combustion engine equipped with an exhaust turbocharger. Therefore, it can be used industrially.

1 Cylinder head 1a Intake side 1b Exhaust side 1c Rear side (one short side)
9 Exhaust gas collection passage 10 Exhaust turbo supercharger 11 Turbine housing 12 Compressor housing 14 Exhaust gas outlet 15 Intake inlet 16 Exhaust gas introduction passage 19 Catalyst case 20 Intake outlet 30 Intercooler (surge tank)
31 Intake manifold 37 Throttle body
38 Supercharging passage 39 EGR pipe 40 Air cleaner 41 Intake passage

Claims (1)

The exhaust turbo supercharger is arranged on one short side of the cylinder head perpendicular to the intake side and the exhaust side, with the turbine housing located on the exhaust side and the compressor housing positioned on the intake side. The configuration is arranged such that
An exhaust gas collecting passage is open on one short side of the cylinder head, and a turbine housing of the exhaust turbo supercharger is fixed to one short side of the cylinder head while communicating with the exhaust gas collecting passage. The compressor housing of the exhaust turbo supercharger is arranged with the intake outlet facing the cylinder head side ,
An intake manifold including an intercooler and through which intake air branches from the intercooler into branch passages is fixed to the intake side of the cylinder head , and the intake outlet of the compressor housing of the exhaust turbocharger is connected to the intake manifold . connected to the intercooler via a supercharging passage and a throttle valve arranged on the outside of the cylinder head so as to face the intercooler;
Internal combustion engine equipped with an exhaust turbo supercharger.

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