JPS6067732A - Internal-combustion engine controlled for operation of divided group of cylinders - Google Patents

Abstract

PURPOSE:To prevent the high-temperature exhaust gas of a working group of cylinders from entering into a resting group of cylinders and thermally deteriorating their fuel injection valves in an engine in which the resting group of cylinders are put off of operation depending on the running condition of the engine to operate the working group of cylinders. CONSTITUTION:In the operation of all cylinders of an engine, an intake shutoff valve 35 in a second intake passage 7 is opened, an exhaust recycling valve 36 in an exhaust recycling pipe 9 is closed, and the driver 51 for a waste gate valve 48 in a second turbocharger 42 is connected to an intake pipe 5. In the slow and rapid operation of the engine, a shutoff valve 31 in a communication passage 8 is opened. In the medium-speed operation of the engine, the shutoff valve 31 is closed. The intake efficiency of the engine is thus heightened. When the output power of the engine has dropped below a prescribed level, the intake shutoff valve 35 is closed and the exhaust recycling valve 36 is opened so that no intake is supplied from the intake cylinder 5 to a second group B of cylinders. At that time, the driver 51 for the valve 48 is connected to the atmosphere to move a diaphragm 53 leftward by a spring 54 to forcibly close the valve.

Description

DETAILED DESCRIPTION OF THE INVENTION TECHNICAL FIELD The present invention relates to a split operation control type internal combustion engine that suspends operation of some cylinder groups depending on the engine state and performs partial cylinder operation.

BACKGROUND ART In an internal combustion engine configured to control engine load by a throttle valve, the fuel consumption rate worsens as the opening degree of the throttle valve decreases. In order to improve this fuel consumption rate, a split-operation control type internal combustion engine has been developed, in which when the engine load is low, the operation of some cylinder groups is completely stopped and the remaining cylinder groups are operated at high load. Are known. Now, in such an internal combustion engine, the first cylinder group, which is always in operation, and the second cylinder group, which is temporarily inactive, each have their own tarpaulin. If a charger is installed, please install a charger on the second cylinder group side. If the charger's waste dart/lube were to open while the charger was at rest, high-temperature gas from the operating first cylinder group would flow into the second cylinder group, causing the fuel injection valves on the second cylinder group to This will result in thermal deterioration. Therefore, in the internal combustion engine, it is necessary to take measures to prevent the high temperature gas discharged from the first cylinder group from flowing into the second cylinder group which is inactive.

Purpose of the Invention In view of the above points, the present invention provides a split operation system in which there is no risk of high humidity gas discharged from the Rin 1 cylinder group mixing into the idle 2nd cylinder group and causing thermal deterioration noise of the fuel injection valve. ! The overall purpose is to provide an I-style internal combustion engine.

114 Achievements of the Invention A split operation control type internal combustion engine according to the present invention comprises a first cylinder which is constantly operated and a second cylinder group which is temporarily inactive, and a second cylinder which is connected to the first cylinder group. One tar?
Nayazoya and the second cylinder connected to the second cylinder group?
It is fully equipped with a charger and a Westgut Palso which can open and close the passage that completely bypasses the turbine of this second turbocharger. Westok.

- the tonnoclub closes said passage while the cylinders of the second cylinder group are inactive;

Actual gun example The present invention will be explained below with reference to the illustrated embodiments.

The figure shows a six-cylinder internal combustion engine, and the cylinders are divided into a first cylinder group A, which is always activated, and a second cylinder group B, which is inactive when the engine output is under low load. The first Zano tank 1 is a branch pipe 11
．． 12.13 to the cylinders 21, 22 .
1 series each on the 23rd! The first exhaust manifold 2 is likewise connected to these cylinders 21, 22, 23. The second surge tank 3 also has branch pipes 14, 15. '16'
Th to cylinders 24, 25, and 26 of the second cylinder group B.
The second exhaust manifold 4 is similarly connected to these cylinders 24, 25, and 26. Each branch pipe 11-1
6 are each provided with a fuel injection valve (not shown).

The downstream portion of the intake passage 5 is divided into a first intake passage 6 and a second intake passage 7.
, 7 are connected to the first and second surge tanks 1.3, respectively.The first and second intake passages 6, 7 extend substantially parallel to each other and are disposed close to each other, They can communicate with each other through a communication path 8. That is, this communication passage 8 is provided with an on-off valve 31, and the I and second intake passages 6, 7 are communicated with each other or are blocked via the on-off valve 31. The on-off valve 31 is driven by a DC motor via an electronic control unit (not shown).

2.71 and the second throttle valve 32.7 on the upstream side of the communication passage 8 of the first and vJ2 intake passages 6.
33 are arranged. These throttle valves 32, 33 are fixed to a common throttle shaft 34 connected to an accelerator pedal (not shown), and change the flow area of the first and second intake passages 6.7 in conjunction with the accelerator pedal. On the other hand, an intake cutoff valve 35 is provided downstream of the communication passage 8 of the second intake passage 7 . The intake cutoff valve 35 is driven by a DC motor (not shown) provided near the second intake passage 7, and is opened when all cylinders are operated, and when the second cylinder group B is inactive, the second The intake passage 7 is closed. Furthermore, this D
The C motor is also controlled by the electronic control unit.

First exhaust manifold 2 and second exhaust manifold 4
have a first turbocharger 41 and a second turbocharger, respectively. Charger 42 exhaust turbine 43.44 crab JL
071 for exhaust of exhaust turbine 43.44
．． 72 is connected to the common υF trachea 45. An oxygen concentration detector 46 is attached to the merging portion of the exhaust pipe 45, and this detector 46 is connected to the electronic control unit to control the air-fuel ratio. Note that a three-way catalytic converter (not shown) is provided in the exhaust pipe 45. On the other hand, each compressor 49°5 of Tase charger 4], , 42
The discharge sides 73, 74 of 0 are connected to the intake passage 5, and the suction sides 75, 76 are connected to a common air cleaner (not shown).

At the beginning of each of the exhaust turbines 43 and 44, in the vicinity of the air intake lowers 7 and 78, waste gas valves 47 and 48 are provided to allow exhaust gases that are about to flow in to escape directly to the air pipes 45. 1st ter d? The valve 47 of the shaft 41 is directly connected to the intake passage 5, and its opening and closing are controlled by the pressure within this pipe.

West gear nozzle 4 of second turbocharger 42
8 is controlled to open and close by the pressure within the intake passage 5 or atmospheric pressure via the drive device 51. The drive device 51 includes a shell 52
The interior is partitioned by a diaphragm 53, and a spring 54 is provided in the constant pressure chamber, so that the inside of the variable pressure chamber 55 can be connected to the intake passage 5 or the atmosphere, and the constant pressure chamber side of the diaphragm 53 is connected to the waist r-) pulp 48. Ru. Switching between the variable pressure chamber 55 and the intake passage 5 or the atmosphere is performed by the electronic control unit. That is, the electronic control unit connects the variable pressure chamber 55 to the intake passage 5 during all-cylinder operation, and the waste (l'-) pulp 48 is controlled to open and close in the normal manner. On the other hand, during partial cylinder operation, the electronic control unit opens the variable pressure chamber 55 to the atmosphere, and the waste gate pulp 48 is biased by the spring 54 and forcibly closed.

The second exhaust manifold 4 and the second surge tank 3 are interconnected by an exhaust gas recirculation pipe 9. This exhaust gas recirculation pipe 6
0 is connected to the exhaust manifold 4 on the upstream side of the turbine 44 of the second turp charger 42, and
．． This is the part where the output tubes extending from 24 and 25 come together. An exhaust gas recirculation valve 36 for opening and closing the exhaust gas recirculation pipe 9 is provided at the connection portion of the exhaust gas recirculation pipe 9 with the surge tank 3 . exhaust,
The reflux valve 36 is controlled by the electronic control unit.

Therefore, the exhaust gas recirculation valve 36 opens the exhaust gas recirculation pipe 9 during partial cylinder operation, thereby causing the second surge tank 3 and the cylinder 2
4, 25, 26 and the second exhaust manifold 4 are communicated via the exhaust gas recirculation pipe 9, and the pumping loss in the movement of the piston within the cylinder 24, 25, 26 is reduced.

Since the apparatus of this embodiment has the above configuration, it operates as follows.

During all-cylinder operation, the intake cutoff valve 35 opens, the exhaust recirculation valve 36 closes, and the drive section 51 of the waist gate valve 48 is connected to the intake pipe 5.

On the other hand, the inter-closing valve 31 opens the communication passage 8 during low and high engine speeds, and opens the communication passage 8 during predetermined medium speed operation.
occlusion to increase intake efficiency.

Here, when the engine output falls below a certain value, the electronic control unit performs control to stop the cylinders 24, 25, 26' (r).First, the intake cutoff valve 35 closes the second intake passage 7, and then the exhaust recirculation valve 36 opens the inside of the exhaust gas recirculation pipe 9. As a result, the air that has passed through the intake pipe 5 is no longer supplied to the cylinders 24.25. 26 causes almost no pumping loss.During this partial cylinder operation, the on-off valve 31 always leaves the communication passage 8 open.

On the other hand, since the driving part 51 of the varnish)r-) pulp 48 is connected to the atmosphere, the diaphragm 53 is pressed by the spring 54 and is displaced to the left in the figure, and the waste dirt pulp 48 is forcibly closed. As a result.

Even if the engine speed increases during partial cylinder operation and the pressure inside the intake pipe 5 becomes very high, the wastegate valve 48 will not open and the first cylinder 1ff
There is no possibility that the high temperature gas lost from 'A' will flow into the second cylinder tg'F B side. Forcibly closing the waste dart valve 48 during partial cylinder operation in this way
This is particularly effective when the wastegate valve 48 is opened and closed using a pressure other than the pressure inside the intake pipe 5. but,
If the waste gate valve 48 is controlled to open and close only by the pressure in the intake pipe 5, and the pressure does not rise enough to open the waste dart valve 48 during partial cylinder operation, 1. The drive device 51 may be omitted, and the waste gate valve 48 may be connected to the intake passage 5 at all times, similar to the first turbocharger 41.

Therefore, there is no risk that high-temperature gas discharged from the first cylinder group A during partial cylinder operation will flow into the vicinity of the fuel injection valves of the second cylinder group B, and thermal deterioration of these fuel injection valves is reliably prevented. be able to.

Effects of the Invention As described above, according to the present invention, it is possible to reliably prevent high-temperature gas from flowing into the cylinders of the second cylinder group that are inactive.

[Brief explanation of drawings]

The figure shows an embodiment of the present invention, and is a partially sectional plan view. 21.22, 23, 24, 25.26... cylinder, 41
...1st turbocharger, 42...2nd Ku-r
Charger, 44...Turbine, 48...West dirt valve, A...First cylinder group, B...Second cylinder group. Patent Applicant: Toyota Motor Corporation Patent Application Agent Patent Attorney Agency: Akira Moto, Patent Attorney, Kazuyuki Nishidate, Patent Attorney, Kyosuke Nakayama, Patent Attorney, Akira Yamaguchi, Patent Attorney, Masaya Nishiyama

Claims (1)

[Claims] 1. Cylinders (2I, 22
, 23, 24, 25, 26) and the first cylinder group (A)
a first tarp charge (41) connected to the second cylinder group CB); and a second tarp charge (41) connected to the second cylinder group CB).
2), and a wastegate valve (48) that can open and close the passage that completely detours around the turbine (44) of this second tarp charger (42).
8) is a split operation control type internal combustion engine characterized in that the passage is closed while the cylinders of the second cylinder group (B) are at rest.