JPH064333U - Black smoke prevention device for diesel engine - Google Patents

Abstract

(57) [Summary] [Purpose] The purpose is to prevent the generation of black smoke in diesel engines. [Constitution] Air valve is closed, idle switch is ON
Is determined to be OFF or OFF (S11, S1
2). It is determined whether the transmission position is the first or second speed or another speed (S1).
3) Compare the air pressure P in the air tank with the set pressure P ₂ (S14), and in S15, the current engine speed and torque are in the area A pre-assigned by the engine speed and torque, If the current engine speed and air flow rate are in the region B pre-assigned by the engine speed and air flow rate, the air valve 11 is opened (S16). As a result, the air accumulated in the air tank 8 is supplied to the intake manifold 6 via the supply pipe.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a diesel engine, and more particularly to a technique for preventing black smoke from being generated when shifting from idle operation to start or acceleration operation.

[0002]

[Problems to be solved by conventional techniques and devices]

 Conventionally, a diesel engine has a problem in that, when shifting from idle operation to starting or accelerating operation, fuel becomes rich and black smoke is generated. Therefore, in view of the above-mentioned conventional problems, the present invention prevents the fuel from becoming excessively rich at the time of shifting from idle operation to starting or accelerating operation to generate black smoke. The purpose is to prevent.

[0003]

[Means for Solving the Problems]

 Therefore, according to the present invention, as shown in FIG. 1, an air supply means for supplying air to an intake manifold of a diesel engine is provided, and an engine operating state detecting means for detecting an operating state of the engine and the detecting means are provided. A control means is provided for controlling the air supply means so as to supply air to the intake manifold when shifting from idle operation to start or acceleration operation based on the output detection signal.

[0004]

[Action]

 In such a configuration, during the operation state in which the engine shifts from idle operation to start or in the operation state in which it shifts to acceleration operation, air is supplied to the intake manifold, so the fuel rich condition can be eliminated and the air and fuel As a result, the ratio can be maintained appropriately, and as a result, the generation of black smoke can be reduced.

[0005]

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. In FIG. 2 showing the system configuration of an embodiment of the present invention, an intake pipe 4 is connected to an intake port 3 of a cylinder 2 of a diesel engine 1, and fresh air is introduced into the intake pipe 4 via an air cleaner 5. The intake manifold 6 is connected. The intake manifold 6 is provided with an air flow rate sensor 7 for detecting the flow rate of the air flowing through the intake manifold 6.

Here, air supply means for supplying air to the intake manifold 6 is provided. This air supply means includes an air pump 8 driven by the engine 1, an air tank 9 for storing the air supplied from the air pump 8, and a supply pipe for supplying air from the air tank 9 to the intake manifold 6. 10 and an air valve 11 that opens and closes the supply pipe 10.

A pulley 12 is connected to a drive shaft 8 A of the air pump 8, and a belt 14 is wound around the pulley 12 and a pulley 13 driven by the engine 1. Therefore, the air pump 8 is driven by the engine 1 and pumps air to the air tank 9 through the pumping pipe 15. A check valve 16 is provided in the pressure feeding pipe 15. The air tank 9 is provided with an air pressure sensor 17 for detecting the air pressure in the tank 9. The air valve 11 is composed of an electromagnetic opening / closing valve that is driven ON / OFF.

On the other hand, based on the engine operating state detecting means for detecting the operating state of the engine 1 and the detection signal output from the detecting means, the air supply means is used when shifting from idle operation to start or acceleration operation. And a control means for controlling. That is, an engine speed sensor 18, an engine torque sensor 19, a transmission position sensor 20, an idle switch 21, the air flow rate sensor 7 and an air pressure sensor 17 are provided as engine operating state detecting means, and these sensors and switches are provided. The signal output from is input to the controller 22 which constitutes the control means. A control signal is output from the controller 22 to the air valve 11.

The air pump 8 is provided with an electromagnetic clutch (not shown) between the drive shaft of the pump section and the drive shaft 8 A of the pulley 12 side. When the switch is turned on, the drive shaft of the pump section and the drive shaft 8A on the pulley 12 side are disconnected when the switch is turned on, and when the switch is turned off, the connection is performed. The relay 23 is ON / OFF controlled by a command from the controller 22 based on the detection signal output from the air pressure sensor 17.

Next, the control contents of the controller 22 will be described based on the flowcharts of FIGS. 3 and 4. The flow chart of FIG. 3 is a flow of pressure accumulation in the air tank 9, and in step 1 (indicated as S1 in the figure; the same applies hereinafter), the air pressure P in the air tank 9 and the set pressure (determined by the vehicle) P _When it is determined that P ≦ P ₁ by comparing with ₁ , the process proceeds to step 2 and the relay 23 is turned off. As a result, the electromagnetic clutch is turned off, the drive shaft of the pump section and the drive shaft 8A of the pulley 12 side are connected, the engine driving force is transmitted to the air pump 8, and the air tank 8 is driven to the air tank 9. Accumulation is performed.

On the other hand, if it is determined that P> P ₁ , the process proceeds to step 3 to turn on the relay 23. As a result, the electromagnetic clutch is turned on, the connection between the drive shaft of the pump section and the drive shaft 8A of the pulley 12 side is released, the engine drive force is not transmitted to the air pump 8, and pressure is not stored in the air tank 9. . The flow chart of FIG. 4 is a pressure release flow from the inside of the air tank 9. In step 11, the air valve 11 is closed, and the process proceeds to step 12 to determine whether the idle switch 21 is ON or OFF. . If it is ON, the process returns to step 11, and if it is OFF, the process proceeds to step 13.

In step 13, it is determined whether the transmission position is the first or second speed or another speed. If the transmission is the first or second speed, the process proceeds to step 14. If it is any other gear, the process returns to step 11. In step 14, the air pressure P in the air tank 8 is compared with the set pressure P _2, and if it is determined that P ≦ P ₂ , the process returns to step 11, and if it is determined that P> P ₂ , step 15 Proceed to.

In step 15, it is judged whether or not the current engine speed, torque, and the flow rate of air flowing through the intake manifold are within a predetermined range, and the operating state is changed from idle operation to start or acceleration operation is performed. Determine whether or not it is operating. That is, the current engine speed and torque are in the area A pre-allocated by the engine speed and torque, and the current engine speed and air flow rate are pre-allocated by the engine speed and air flow rate. If it is in the region B, the flow proceeds to step 16 and the air valve 11 is opened. As a result, the air accumulated in the air tank 8 is supplied to the intake manifold 6 via the supply pipe. If it is not in the area A, or if it is not in the area B, wait until it becomes the areas A and B.

According to such a configuration, air is supplied to the intake manifold 6 during an operating state in which the engine shifts from idle operation to start or in an operating state in which acceleration operation is performed, so that the fuel rich state can be eliminated. As a result, the ratio of air and fuel can be maintained appropriately, so that the generation of black smoke can be reduced. Next, another embodiment of the present invention will be described with reference to FIGS.

In this embodiment, the pressure stored in the air tank may be stored in the turbocharger of the engine 1. That is, in FIG. 5, the air supply means for supplying air to the intake manifold 6 is an air tank 9 and a communication pipe that connects the air tank 9 and the intake manifold 6 downstream of the intake compressor 25 of the turbocharger 26. 28 and an air valve 11 that opens and closes the communication pipe 28.

As in the embodiment of FIG. 2, the air tank 9 is provided with a first air pressure sensor 27 for detecting the air pressure in the tank 9. Further, the intake manifold 6 is provided with a second air pressure sensor 37 for detecting the air pressure in the intake manifold 6. On the other hand, as engine operating state detecting means, an engine speed sensor 18, an engine torque sensor 19, a transmission position sensor 20, an idle switch 21, the air flow rate sensor 7, a first air pressure sensor 27 and a second air pressure sensor 3 are provided. 7 are provided, and the signals output from these sensors and switches are input to the controller 22. The controller 22 outputs a control signal to the air valve 11.

Next, the control content of the controller 22 will be described based on the flowchart of FIG. In step 21, the air pressure PI in the intake manifold 6 is compared with a set pressure (determined by the vehicle) P, and if it is determined that PI ≦ P, the process proceeds to step 22 to close the air valve 11, Proceed to 23. If it is determined that PI> P, the routine proceeds to step 24, where the air pressure PA in the air tank 9 and the air pressure PI in the intake manifold 6 are compared, and if PA ≧ PI, the pressure in the air tank 9 is accumulated. Is completed, the routine proceeds to step 25, the air valve 11 is closed, and the routine returns to step 21. If PA <PI, pressure accumulation in the air tank 9 has not been completed, so the routine proceeds to step 26, the air valve 11 is opened, and the routine returns to step 21.

On the other hand, in step 23, it is determined whether the idle switch 21 is ON or OFF. If it is ON, the process returns to step 21, and if it is OFF, the process proceeds to step 27. In step 27, it is judged whether the transmission position is the first or second speed or another speed. If the transmission position is the first or second speed, the process proceeds to step 28 and the other speed is selected. If it is a shift speed, the process returns to step 21.

In step 28, the air pressure PA in the air tank 9 is compared with the air pressure PI in the intake manifold 6, and if PA ≧ PI, the pressure accumulation in the air tank 9 has been completed, so the routine proceeds to step 29. . If PA <PI, the process returns to step 21. In step 29, the current engine speed and torque are in the area A pre-allocated by the engine speed and torque, and the current engine speed and air flow rate are pre-allocated by the engine speed and air flow rate. If it is in the area B, the flow proceeds to step 30 and the air valve 11 is opened. As a result, the pressure-accumulated air in the air tank 9 is supplied to the intake manifold 6 via the communication pipe 28. If it is not in the area A, or if it is not in the area B, wait until it becomes the areas A and B.

Even in such a configuration, the ratio of air and fuel can be maintained appropriately, and as a result, the generation of black smoke can be reduced. As described above, the present invention has been described with reference to the specific embodiments, but the present invention is not limited thereto, and is attached to the present invention by a person skilled in the art. It should be noted that various changes and modifications can be made without departing from the scope of claims for utility model registration.

[0021]

[Effect of device]

 As described above, according to the present invention, the air is supplied to the intake manifold at the time of shifting from the idle operation to the start or acceleration operation, so that the ratio of air and fuel can be appropriately maintained. As a result, the practical effect of reducing the generation of black smoke is great.

[Brief description of drawings]

FIG. 1 is a block diagram of the present invention.

FIG. 2 is a system diagram showing an embodiment of the same device.

FIG. 3 is a flowchart for explaining the operation of the above embodiment.

FIG. 4 is a flowchart for explaining the operation of the above embodiment.

FIG. 5 is a system diagram showing another embodiment.

FIG. 6 is a flowchart for explaining the operation of the above embodiment.

[Explanation of Codes] 1 Diesel engine 6 Intake manifold 7 Air flow sensor 8 Air pump 9 Air tank 10 Supply pipe 11 Air valve 17 Air pressure sensor 18 Engine speed sensor 19 Engine torque sensor 20 Transmission position sensor 21 Idle switch 22 Controller 25 Intake Compressor 27 First air pressure sensor 28 Communication pipe 37 Second air pressure sensor

Claims (1)

[Scope of utility model registration request] 1. An idling operation based on an engine operating state detecting means for detecting an operating state of the engine by providing air supplying means for supplying air to an intake manifold of a diesel engine, and a detection signal output from the detecting means. And a control means for controlling the air supply means so as to supply air to the intake manifold when shifting from start to acceleration operation.