JPH06123256A - Exhaust gas recirculation controller for internal combustion engine with speed governor - Google Patents

Abstract

PURPOSE:To control supply of exhaust gas recirculation amount precisely even in unstable governing behavior area by freely controlling the exhaust gas recirculation amount, for which driving stability and power within the whole of engine performance areas including idling are considered. CONSTITUTION:In an internal combustion engine with a speed governor provided with an air speed governor 2 between a carburetor 1 and an intake manifold 3, a negative pressure generation side of an engine driven vacuum pump 10 is connected to a negative pressure operation chamber 42 of an exhaust gas recirculation control valve 40 via a flow rate variable electromagnet valve 12, while a valve element 44 of the exhaust gas recirculation valve 40 is arranged in an exhaust gas recirculation passage, and signals from an engine rotation sensor 62 and an intake negative pressure sensor 63 of the intake manifold 3 are inputted to be compared with the previously memorized data and are selected so as to operate the flow rate variable electromagnet valve 12. An electronic control unit, which regulates the negative pressure to be transmitted to the negative operation chamber 42 of the exhaust gas recirculation control valve 40 up to the optimum negative pressure, is installed so as to control the opening of the valve element 44, in other words, the exhaust gas recirculation amount.

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 system capable of controlling exhaust gas recirculation so as to maintain operational stability of an internal combustion engine with a speed governor.

[0002]

2. _Description of the Related Art It is known that a part of exhaust gas is recirculated into intake air as a technique for reducing NO _x emitted from an internal combustion engine. Generally, when the exhaust gas recirculation rate is increased, the NO _x reducing effect is increased. However, because of this, the drivability and the fuel economy also deteriorate, so the optimal control is performed so that the amount of recirculation corresponds to the engine operation. The speed regulation performance range of an internal combustion engine equipped with an air governor is less stable in operation when the operating load is lighter than in other performance ranges, and even more stable when exhaust gas is uniformly recirculated. In this speed control performance range, it has been desired to develop an exhaust gas recirculation control device capable of optimally controlling the exhaust gas recirculation amount according to the load.

[0003]

SUMMARY OF THE INVENTION The present invention provides an exhaust gas recirculation control device for an internal combustion engine with an air speed governor, which can control the amount of exhaust gas recirculation so as to always maintain operational stability in a speed control performance range. It is what

[0004]

The present invention relates to an internal combustion engine with a speed governor in which an air speed governor is arranged between a carburetor and an intake manifold, and a negative flow generating side of a vacuum pump driven by the engine is controlled by a variable flow electromagnetic. The valve body of the exhaust gas recirculation control valve connected to the negative pressure working chamber of the exhaust gas recirculation control valve via the valve is arranged in the exhaust gas recirculation passage connected to the intake manifold, and engine rotation is performed. Negative pressure transmitted to the negative pressure operating chamber of the exhaust gas recirculation control valve by inputting signals from the sensor and the intake negative pressure sensor of the intake manifold, comparing and selecting with data stored in advance, and operating the variable flow solenoid valve An exhaust gas recirculation control device for an internal combustion engine with a speed governor, characterized in that an electronic control unit for adjusting the pressure is provided.

[0005]

The negative pressure generated in the vacuum pump driven by the engine operates the exhaust gas recirculation control valve via the variable flow solenoid valve to control the exhaust gas recirculation amount. At that time, the engine rotation sensor and the intake negative pressure sensor of the intake manifold are controlled. Input the signal from and to the electronic control unit, compare and select with desired data stored in advance, operate the variable flow solenoid valve to adjust the negative pressure to operate the exhaust gas recirculation control valve to the optimum negative pressure, Controls the exhaust gas recirculation amount. In this way, the exhaust gas recirculation amount can be freely controlled in consideration of the operating stability and output required by the engine in the entire engine performance region including idling, and the exhaust gas recirculation amount can be accurately controlled even in the unstable speed control performance region. Since the supply can be well controlled, the stability of the engine can be maintained and NOx can be reduced.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a system diagram of an exhaust gas recirculation control device according to the present invention. An air governor 2 is provided downstream of a carburetor 1. The downstream side of the air governor 2 is connected to the intake manifold 3. Reference numeral 4 is a throttle valve of the vaporizer 1, and 5 is a venturi portion. The air speed governor 2 is composed of a speed governor throttle valve 6 and a stabilizer rod 8, and the stabilizer rod 8 is built in the stabilizer section 7. It is pushed by the atmospheric pressure through the air passage 9 and compensates for the closing force of the speed governor throttle valve 6. Reference numeral 10 denotes an engine-driven vacuum pump, which communicates with a negative pressure inlet 13 of a variable flow solenoid valve 12 through an intake passage 11 and a negative pressure discharge port 1 of the variable flow solenoid valve 12.
4 communicates with the venturi portion 5 of the carburetor 1 on the upstream side by the atmosphere passage 15, and further the negative pressure supply port 1 of the variable flow rate solenoid valve 12
Reference numeral 6 is attached to the engine body jacket 21 by a negative pressure passage 17 and is connected to a thermo open / close valve 20 which is opened / closed by its heat. The thermo open / close valve 20 is connected to a charge tank 30 by a negative pressure passage 18. Is connected to the negative pressure operating chamber 42 of the exhaust gas recirculation control valve 40 via the vacuum delay valve 31 by the negative pressure passage 19. The exhaust gas recirculation control valve 40 is divided into a negative pressure working chamber 42 and an atmosphere chamber 43 by a diaphragm 41, and a valve body 44 of the exhaust gas recirculation control valve 40 is connected to an exhaust gas recirculation passage 50 (not shown) and an air recirculation passage 50. Intake passage 3 ₁ downstream of speed machine 2
Is provided between the exhaust gas recirculation passage 51 connected to the
Reference numeral 4 is connected to the diaphragm 41, and the diaphragm 41 is biased by the spring 45 to bias the valve element 44 in the valve closing direction. Further, an electronic control unit 60 is electrically connected to the variable flow solenoid valve 12, and a flywheel tooth surface 61 is connected to the electronic control unit 60.
The engine rotation sensor 62 that obtains a rotation signal from the intake manifold 3 is electrically connected to the intake negative pressure sensor 63 that obtains a negative pressure signal from the intake manifold 3, and the electronic control unit 60 uses the rotation sensor 62 and the intake negative pressure sensor 63. Signal is input to compare and select data stored in advance to operate the variable flow rate solenoid valve 12 to regulate the negative pressure transmitted to the negative pressure operating chamber 42 of the exhaust gas recirculation control valve 40.

Thus, the mixed gas supplied by the vaporizer 1 passes through the air governor 2 and is supplied to the intake manifold 3. On the other hand, the vacuum pump 10 is driven by the engine and the negative pressure inlet 13 of the variable flow rate solenoid valve 12 is driven by the intake passage 11.
And from the negative pressure supply port 16, the negative pressure passage 17, the thermostat valve 20, the negative pressure passage 18, the charge tank 30, the negative pressure passage 1
9. A negative pressure is applied to the negative pressure operating chamber 42 of the exhaust gas recirculation control valve 40 via the vacuum delay valve 31, and the opening degree of the valve element 44 is controlled according to the negative pressure. The amount of exhaust gas recirculation in the passage 50 is controlled. As described above, the exhaust gas recirculation control valve 40 is operated and the exhaust gas recirculation is performed by the negative pressure supplied via the variable flow electromagnetic valve 12, and the optimum recirculation amount is from the variable flow electromagnetic valve 12 by the electronic control unit 60. It is controlled by the negative pressure supplied to the exhaust gas recirculation control valve 40. For example, as shown in FIG. 2, the rotation signal of the engine rotation sensor 62 and the negative pressure signal of the intake negative pressure sensor 63 are waveform-shaped and input to the electronic control unit 60, and desired data is stored in advance.
Contact OM65 and data bus 64 to compare and select, I
/ O input / output interface 66 is used to perform optimum opening / closing control of the variable flow rate solenoid valve 12.
That is, a part of the negative pressure applied to the negative pressure inlet 13 due to the variable opening / closing of the variable flow solenoid valve 12 is leaked to the atmosphere passage 15 through the negative pressure outlet 14, and is optimally supplied to the negative pressure passage 17 through the negative pressure supply port 16. The pressure is supplied, and the exhaust gas recirculation control valve 40 is supplied through the charge tank 30 and the vacuum delay valve 31.
Is optimally controlled.

The thermo-on / off valve 20 is opened / closed by a cooling water jacket 21 of the engine body, and becomes conductive at a predetermined temperature, and becomes non-conductive at a predetermined temperature or lower, and the negative pressure is shut off when the engine is cold. The exhaust gas recirculation control valve 40 does not operate and exhaust gas recirculation is not performed. Also, the charge tank 30
Is for supplementing the vacuum delay valve 31 which absorbs the fluctuation of the negative pressure acting on the negative pressure operating chamber 42 of the exhaust gas recirculation control valve 40, and absorbs the fluctuation of the negative pressure to reduce the fluctuation of the exhaust gas recirculation amount, Keeps driving stability.

[0009]

As described above, according to the present invention, in an internal combustion engine with a speed governor in which an air speed governor is arranged between a carburetor and an intake manifold, the negative pressure generating side of a vacuum pump driven by the engine is variable in flow rate. An exhaust gas recirculation control valve connected to the negative pressure working chamber of the exhaust gas recirculation control valve via a solenoid valve, and the valve body of the exhaust gas recirculation control valve connected to the negative pressure working chamber is disposed in the exhaust gas recirculation passage connected to the intake manifold; Signals from the rotation sensor and the intake negative pressure sensor of the intake manifold are input and compared / selected with prestored data to operate the variable flow solenoid valve to transfer it to the negative pressure operating chamber of the exhaust gas recirculation control valve. By providing an electronic control unit that regulates the pressure, it is possible to freely control the exhaust gas recirculation amount in consideration of the operating stability and output required by the engine for the entire engine performance range including idling. Because it accurately supply control the exhaust gas recirculation amount in governor performance range is unstable, that it is possible to reduce other NOx to maintain stability of the engine, is intended to achieve the Naru extremely beneficial effect.

[Brief description of drawings]

FIG. 1 is a system diagram showing an embodiment of the present invention.

FIG. 2 is a basic configuration diagram of an electronic control unit of the present invention.

[Explanation of symbols]

1 Vaporizer 2 Air governor 3 Intake manifold 3 ₁ Intake passage 4 Throttle valve 5 Venturi section 6 Governor throttle valve 7 Stabilizer rod 8 Stabilizer section 9 Atmosphere passage 10 Vacuum pump 11 Intake passage 12 Flow rate variable solenoid valve 13 Negative Pressure inlet 14 Negative pressure discharge port 15 Atmosphere passage 16 Negative pressure supply port 17 Negative pressure passage 18 Negative pressure passage 19 Negative pressure passage 20 Thermo open / close valve 21 Engine body cooling water jacket 30 Charge tank 31 Vacuum delay valve 40 Exhaust gas recirculation control valve 41 diaphragm 42 negative pressure working chamber 43 atmosphere chamber 44 valve body 50 exhaust gas recirculation passage 51 exhaust gas recirculation passage 60 electronic control unit 61 flywheel tooth surface 62 engine rotation sensor 63 intake negative pressure sensor 64 data bus 65 ROM 66 I / O input / Output interface

Claims (2)

[Claims] 1. In an internal combustion engine with a speed governor in which an air speed governor is arranged between a carburetor and an intake manifold, a negative pressure generating side of a vacuum pump driven by an engine is controlled by an exhaust gas recirculation control valve via a variable flow solenoid valve. Of the exhaust gas recirculation control valve connected to the negative pressure working chamber of the engine and the exhaust gas recirculation passage connected to the intake manifold. An electronic control unit is provided for inputting a signal from a sensor, comparing and selecting the data stored in advance and operating the variable flow rate solenoid valve to regulate the negative pressure transmitted to the negative pressure operating chamber of the exhaust gas recirculation control valve. An exhaust gas recirculation control device for an internal combustion engine equipped with a speed governor. 2. A thermo opening / closing valve, which is attached to a cooling water jacket of the engine body and shuts off the negative pressure passage at a predetermined temperature or less, is provided in the negative pressure passage between the negative pressure working chambers of the variable flow solenoid valve and the exhaust gas recirculation control valve. An exhaust gas recirculation control device for an internal combustion engine with a speed governor according to claim 1.