JPH09264202A - Exhaust recirculation device for engine provide with inertia supercharger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten the length of an EGR (exhaust gas recirculation) pipe so as to accomplish compactification and so as to facilitate installation to a vehicle when an exhaust recirculation device is arranged in an engine provided with an inertia supercharger. SOLUTION: An intake manifold 2 is divided into two groups, each of which consists of three cylinders, and in branched pipe 2a gathering parts of intake manifolds 2A, 2B in each group, branch intake pipes 5A 5B, which are branched from a single intake pipe 5 into two pipes and are provided with the predetermined lengths, are connected individually, and consequently, an engine provided with an inertia supercharger is constructed. Each of branch EGR pipes 13A, 13B, which are branched from an EGR pipe 13 connected to an exhaust manifold 1, is connected to one branched pipe 2a in each of the intake manifolds 2A, 2B in the respective groups, and each of EGR control valves 14A, 14B controlling EGR is arranged in each of the branch EGR pipes 13A, 13B.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exhaust gas recirculation (hereinafter referred to as "EGR") device for an inertial overpayment engine, and more particularly to an EGR pipe piping technique.

[0002]

2. Description of the Related Art Conventionally, an EGR device for recirculating a part of exhaust gas to an intake system is known as one of the techniques for reducing the amount of NOx generated in an internal combustion engine. As this EGR device, conventionally, as shown in FIG. 5, exhaust gas (EGR gas)
There is known a structure in which the exhaust manifold 1 and the intake manifold 2 are circulated to the intake system via an EGR pipe 3 which communicates with the downstream of each branch pipe 2a collecting portion of the intake manifold 2 (Japanese Utility Model Publication No. 61-95968). reference).

The EGR pipe 3 has an E for controlling the EGR.
The GR control valve 4 is interposed.

[0004]

EG having such a structure
As shown in FIG. 6, the R device divides the intake manifold 2 into two groups each having a plurality of cylinders (2A, 2
B), intake manifolds 2A, 2B of each group
The branch intake pipes 5a and 5B each having a predetermined length branched from the single intake pipe 5 are connected to the respective branch pipes 2a.
Inertia of a configuration in which a communication pipe 6 that communicates one branch pipe 2a of each intake manifold 2A, 2B of each group is provided, and an inertia supercharging control valve 7 for controlling inertia supercharging is provided in the communication pipe 6. E when applied to an overpayment engine
The GR pipe 3 is a long pipe from the exhaust manifold 1 to the single intake pipe 5.

When the EGR pipe 3 is elongated in this way, it becomes difficult to mount it on the vehicle. In view of the above conventional problems, it is an object of the present invention to shorten the EGR pipe to make it compact and facilitate vehicle mounting when an exhaust gas recirculation device is provided in an inertia over-fitting engine. .

[0006]

Therefore, in the invention according to claim 1, the intake manifold is divided into two groups of a plurality of cylinders, and the intake manifold of each group has a single branch pipe collecting portion. In the inertia over-benefits engine in which the branched intake pipes of a predetermined length branched from the intake pipe are respectively connected, the exhaust gas recirculation pipe connected to the exhaust pipe is
Each of the branched exhaust gas recirculation pipes is connected to one branch pipe of each intake manifold of each group, and an exhaust gas recirculation control valve for controlling exhaust gas recirculation is provided in each of the branched exhaust gas recirculation pipes.

According to a second aspect of the present invention, the intake manifold is divided into two groups of a plurality of cylinders, and a predetermined intake pipe is branched into two at each branch pipe collecting portion of each intake manifold of each group. In an inertia overcharge engine in which branched intake pipes each having a length are connected, a communication pipe for communicating one branch pipe of each intake manifold of each group is provided, and the inertia supercharge for controlling inertia supercharging is provided in the communication pipe. 2 which is connected to the exhaust pipe while interposing a control valve
One exhaust gas recirculation pipe was connected to each intake manifold of each group, and an exhaust gas recirculation control valve for controlling exhaust gas recirculation was interposed in each of the exhaust gas recirculation pipes.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 shows an embodiment of the invention according to claim 1. In this figure, the intake manifold 2 is divided into two groups each having a plurality of cylinders (three cylinders in this embodiment), and a single intake pipe is provided at a branch pipe 2a collecting portion of each intake manifold 2A, 2B of each group. Branch intake pipe 5 with a predetermined length branched from 5
A and 5B are connected to each other to form an inertial overpayment engine.

On the other hand, the EGR pipe 13 connected to the exhaust manifold 1 is branched from the EGR pipe 13 into two.
3A and 13B are connected to one branch pipe 2a of each intake manifold 2A and 2B of each group,
EGR control valves 14A and 14B for controlling EGR are provided in the branched EGR pipes 13A and 13B, respectively. In this case, the EGR pipe 13 is laid out so as to extend from the exhaust manifold 1 along the side of the engine body E and then along the upper surface of the engine body E.

EGR control valve control means is provided for controlling the operation of the EGR control valves 14A and 14B based on engine operating conditions such as engine speed and load, and the control unit 18 functions as this control means. Is equipped with software. That is, the control unit 18 includes a rotation sensor 1 for detecting the engine speed.
The rotation speed signal output from 9 and the load signal output from the load sensor 20 are input, and the control unit 1
A control signal is output from 8 to the EGR control valves 14A and 14B.

Next, the control contents of the control means are shown in FIG.
It is executed as shown in the flowchart of FIG. That is, in the flowchart, in step 1 (abbreviated as S1 in the figure; the same applies hereinafter), the engine speed and load are read. If it is determined in step 2 that the operating condition for performing EGR is determined based on the read engine speed and load, the process proceeds to step 3 and the two EGR control valves 1
4A and 14B are controlled to be open, and if it is determined that the operating conditions are such that EGR is not performed, the routine proceeds to step 4, where two E
The GR control valves 14A and 14B are controlled to be closed.

EGR based on engine speed and load
The areas are as shown in the map. Here, when the EGR control valves 14A and 14B are closed as described above, the communication between the branch pipes 2a of the intake manifolds 2A and 2B is cut off, so that the conventional inertia supercharging pipe shown in FIG. Similar to the form, the inertia supercharging effect is obtained.

Further, when the EGR control valves 14A and 14B are opened to perform the EGR, the inertia supercharging effect cannot be obtained, but the pumping loss is reduced and the fuel consumption is improved, and the EGR is performed. As the gas can be mixed well with the intake air,
The NOx reduction effect can be improved. FIG. 4 shows an embodiment of the invention according to claim 2.

In this figure, a communication pipe 16 is provided for communicating one branch pipe 2a of each intake manifold 2A, 2B of each group, and the communication pipe 16 has an inertia supercharging control valve for controlling inertia supercharging. 17 is interposed. or,
Two EGRs connected to the exhaust manifold 1
The pipes 23A and 23B are respectively connected to the intake manifolds 2 of the respective groups, and the EGR pipes 23
Each of A and 23B has an EGR control valve 2 for controlling EGR.
4A and 24B are interposed.

In this case, the two EGR tubes 23A and 23B
Are laid out so as to extend along the side of the engine body E from the exhaust manifold 1. Then, E that controls the operation of the EGR control valves 24A and 24B is based on the engine operating conditions such as the engine speed and the load.
The GR control valve control means and the inertial supercharging control valve control means for controlling the operation of the inertial supercharging control valve 17 are provided, and the functions of these control means are the control unit 1
Equipped with 8 software.

In this embodiment, the inertial supercharging control valve 1 is irrespective of whether the EGR control valves 24A and 24B are opened or closed.
By opening and closing 7, you can control the presence or absence of inertia supercharging,
It is also possible to execute EGR and inertial supercharging at the same time. In each of the above-described embodiments, even when the EGR device is applied to the inertia overpayment engine, E
There is an advantage that the GR pipe does not become a long pipe, and the EGR pipe is shortened and made compact to facilitate vehicle mounting.

[0017]

As described above, according to the first and second aspects of the present invention, the exhaust gas recirculation pipe of the exhaust gas recirculation device in the inertia overfitting engine can be shortened and made compact, and the vehicle can be easily mounted. There is. In particular, according to the invention of claim 1, when the exhaust gas recirculation control valve is opened and exhaust gas recirculation is performed, the inertia supercharging effect cannot be obtained, but the pumping loss is reduced and the fuel consumption is reduced. In addition to improving the NOx reduction effect, the exhaust gas recirculation gas can be mixed well with the intake air.

According to the second aspect of the present invention, the presence or absence of inertia supercharging can be controlled by opening and closing the inertia supercharging control valve regardless of whether the exhaust recirculation control valve is opened or closed. It is also possible to carry out supercharging at the same time. .

[Brief description of drawings]

FIG. 1 is a system diagram showing an embodiment of the invention according to claim 1.

FIG. 2 is a flowchart illustrating the control contents of the control means in the above embodiment.

FIG. 3 EGR map

FIG. 4 is a system diagram showing an embodiment of the invention according to claim 2;

FIG. 5 is a system diagram showing a conventional EGR device.

FIG. 6 EGR in a conventional engine with inertia supercharging
System diagram showing the device

[Explanation of symbols]

 1 Exhaust Manifold 2 Intake Manifold 2A, 2B Intake Manifold 2a Branch Pipe 5 Intake Pipe 5A, 5B Branch Intake Pipe 13 EGR Pipe 13A, 13B Branch EGR Pipe 14A, 14B EGR Control Valve 16 Communication Pipe 17 Inertial Supercharging Control Valve 23A, 23B EGR pipe 24A, 24B EGR control valve

Claims (2)

[Claims] 1. An intake manifold is divided into two groups each having a plurality of cylinders, and a branch intake pipe of a predetermined length is branched from a single intake pipe into a branch pipe collecting portion of each intake manifold of each group. In the inertia over-energy engine in which each of the intake manifolds is connected to each other, each of the branch exhaust gas recirculation pipes branched from the exhaust gas recirculation pipe connected to the exhaust pipe is connected to one branch pipe of each intake manifold of each group, An exhaust gas recirculation system for an inertia over-utilization engine, wherein an exhaust gas recirculation control valve for controlling exhaust gas recirculation is provided in each of the exhaust gas recirculation pipes. 2. An intake manifold is divided into two groups each having a plurality of cylinders, and a branch intake pipe of a predetermined length is branched from a single intake pipe into a branch pipe collecting portion of each intake manifold of each group. In the inertia overcharge engine in which each of the intake manifolds is connected to each other, a communication pipe that communicates one branch pipe of each intake manifold of each group is provided, and an inertia supercharge control valve that controls the inertia supercharge is provided in the communication pipe. On the other hand, two exhaust gas recirculation pipes connected to the exhaust pipes are connected to the intake manifolds of the respective groups, and an exhaust gas recirculation control valve for controlling exhaust gas recirculation is provided in each of the exhaust gas recirculation pipes. Exhaust gas recirculation system for inertial overpaid engines.