JPS5891346A - Control device for engine - Google Patents

Abstract

PURPOSE:To restrain the vibration of an engine and simplify the construction thereof by a method wherein a weight for regulating quantity of combustion fluid by an inertia force corresponding to the vibration of the engine, and a delay device delaying the operation of the weight, are provided in the device. CONSTITUTION:When the engine 1 is vibrating, the weight 16 is operated into a direction to open a valve body 17 and air is introduced into the vacuum chamber 6d of a recirculation control valve 6 through an air releasing path 15. According to this operation, the recirculation control valve 6 is closed and the amount of recirculated exhaust gas is reduced and regulated, therefore, the vibration of the engine may be restrained. At this time, the operation of the valve body 17 is delayed by a delay device 22 (orifice 21) and is effected slowly, therefore, surging phenomenon will never be caused. Thus, the control to obtain the stable combustion condition of the engine 1 may be effected smoothly and prperly.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an engine control device, and more particularly, to a control device for an engine, which controls a fluid that controls the combustion state of the engine according to the combustion state of the engine, such as recirculated exhaust gas, intake air for air-fuel ratio control,
This invention relates to a device that controls the amount of intake negative pressure, etc., which is used as an operating source for ignition timing control.

Conventionally, as disclosed in Japanese Patent Application Laid-Open No. 54-91623, etc., there has been a conventional control device for this type of engine that controls the engine when the combustion state of the engine becomes unstable, such as unstable combustion or misfire. Since vibration occurs, this engine vibration is detected and the amount of fluid that governs the combustion state of the engine, such as the recirculated exhaust gas and intake air, is controlled in a direction that stabilizes the combustion state of the engine, thereby suppressing engine vibration. It is known what has been suppressed.

However, in the conventional system described above, engine vibrations caused by an unstable combustion state of the engine are detected by a vibration sensor, and the amount of fluid such as recirculated exhaust gas is controlled via the stain air circuit based on this detection signal. , which required a complicated electrical circuit and had a complex structure.

In view of the above, the present invention uses a mechanical method instead of the above-mentioned electric method to meter and control the fluid that governs the combustion state of the engine according to the combustion state of the engine.
An object of the present invention is to provide an engine control device that suppresses engine vibration, thereby simplifying the structure.

Furthermore, in the present invention, when the fluid is metered in a direction that makes the combustion state of the engine unstable, its operation is delayed, thereby controlling the amount of fluid without causing a surging phenomenon. It was designed so that it could be carried out accurately.

That is, the present invention controls the combustion state of the engine.
It has a fluid passage through which the fluid passes, and a valve body for adjusting the passage area of the fluid passage, and is supported by the engine via an elastic member and allows the fluid to pass therethrough by an inertial force corresponding to the vibrations of the engine. The present invention is characterized in that it comprises a metering weight and a delay device that delays the operation of the weight when the weight metering the fluid in a direction that makes the combustion state of the engine unstable.

Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings.

FIG. 1 shows a first embodiment in which the present invention is applied to recirculated exhaust gas in an exhaust gas recirculation device as a fluid that controls the combustion state of an engine. In FIG. 1, 1 is an engine, 2 is an intake passage, S is an exhaust passage, and 4 is a throttle valve disposed in the intake passage 2 to control the amount of intake air supplied to the engine 1.

Reference numeral 5 designates an exhaust gas recirculation passage having one end communicating with the exhaust passage 5 and the other end communicating with the intake passage 2 downstream of the throttle valve 4 to recirculate a part of the exhaust gas to the intake passage 2 downstream of the throttle valve 4. There is an exhaust gas recirculation passage 5 in the middle of the exhaust gas recirculation passage 5.
A reflux control valve 6 is provided which controls the opening and closing of the valve to adjust its passage area. The recirculation control valve 6 includes a valve body 6a that opens and closes the exhaust gas recirculation passage 5, and a rod 6b that connects the valve body 6a.
A diaphragm 6C supported via the diaphragm 6C, and a negative pressure chamber 6d and an atmospheric pressure chamber 6e defined by the diaphragm 6C.
and a spring 6f that is compressed in the negative pressure chamber 6d and biases the valve body 6a in the valve closing direction. 4 When fully closed, it communicates with the negative pressure outlet 8 that opens immediately upstream, and during normal operation (excluding idling), the intake negative pressure that acts on the negative pressure outlet 8 is transferred to the negative pressure introduction passage 7 is biased against the biasing force of the diaphragm 6 (4-sph IJ ring 6f), and the valve body 6a is opened via the rod 6b, thereby opening the exhaust gas recirculation passage 5. Open the
An exhaust gas recirculation device 9 is configured to recirculate a part of the exhaust gas to the intake passage 2 via the exhaust gas recirculation passage 5 to suppress the generation of NOx.

As a feature of the present invention, a hollow casing 1o is integrally fixed to the outer wall of the engine 1, and the inside of the casing 10 is partitioned by a diaphragm 11 into a first chamber 12 and a second chamber 15. ), the first chamber 12 is open to the atmosphere via the communication port 14, and the first chamber 12 is open to the atmosphere through the communication port 14.
2, an opening 15a of an atmosphere release passage 15 branched from the middle of the negative pressure introduction passage 7 is provided. Also,
A weight 16 is fixed to the diaphragm 11, and the weight 16 has an opening 15a of the atmosphere opening passage 15.
A valve body 17 is provided for opening and closing to control the amount of air introduced into the air release passage 15, and the weight 16 is supported by a spring compressed in the first and second chambers 12.15. The valve body 17 is elastically supported so as to vibrate in the opening/closing direction (engine vibration direction) by elastic members 18 and 19. Therefore, when the engine vibrates, the valve body 17
The air opening passage 15 is opened, and the atmosphere is introduced from the atmosphere opening passage 15 into the negative pressure chamber 6d of the reflux control valve 6 to dilute the negative pressure in the negative pressure chamber 6d, thereby controlling the reflux. By closing the valve 6 and adjusting the passage area of the exhaust gas recirculation passage 5 to decrease, the amount of exhaust gas recirculation is reduced in a direction that stabilizes the combustion state of the engine 1.

Further, on the side wall of the casing 10 of the second chamber 16, a one-way valve 20 made of a reed valve and an orifice 21 that allow flow from the second chamber 15 to the atmosphere are arranged in parallel, and the weight 16 is connected to the valve body 17. When operating in the valve opening direction (rightward in the figure), that is, when operating to reduce and adjust the amount of recirculated exhaust gas in a direction that stabilizes the combustion state of the engine 1, the pressure in the second chamber 16, which becomes a positive pressure, is reduced. On the other hand, when the weight 16 is actuated in the closing direction of the valve body 17 (toward the left in the figure), contrary to the above, the weight 16 is released into the atmosphere immediately through the valve 20 so as not to impede the operation of the weight 16. , that is, the negative pressure chamber 6d of the reflux control valve 6 is closed by closing the valve body 17.
As the dilution level of the engine 1 decreases, the passage area of the exhaust gas recirculation passage 50 is adjusted to increase by opening the recirculation control valve F6, and the amount of recirculated exhaust gas increases, which causes the combustion state of the engine 1 to become unstable. In some cases, a delay device 22 is configured to delay the operation of the weight 16 by gradually introducing atmospheric air into the second chamber 15, which has a negative pressure, through the orifice 21.

Next, the operation of the first embodiment will be explained. When the combustion state of the engine 1 becomes unstable due to misfire or the like, engine vibration occurs. During this engine vibration, engine 1
While the casing 10 that is integrated with the weight 16 vibrates, the weight 16
remains in place due to its inertial force, so that the weight 16 relatively moves in the direction of opening the valve body 17 (toward the right in the figure). As a result, the opening 15a of the atmosphere opening passage 15 is opened, and the atmosphere is introduced into the negative pressure chamber 6d of the recirculation control valve 6 through the atmosphere opening passage 15, thereby diluting the negative pressure chamber 6d. The recirculation control valve 6 is closed so as to reduce and adjust the passage area of the exhaust gas recirculation passage 5, and the amount of recirculated exhaust gas is adjusted to be reduced.

As a result, the amount of exhaust gas recirculated to the engine 1 is reduced, so that the engine 1 enters a stable combustion state, and engine vibration can be suppressed.

Therefore, engine control according to engine vibration can be performed accurately.

At this time, the weight 16 operates in the valve closing direction (to the left in the figure) of the valve body 17 after the valve body 17 is operated in the valve opening direction due to engine vibration. In other words, the engine 1 operates in a direction that makes the combustion state unstable, but this operation is prevented by the delay device 22.
Since the combustion is performed slowly and delayed by the orifice 21, a surging phenomenon does not occur, and the engine 1 can be smoothly and accurately controlled to a stable combustion state.

Therefore, the engine control corresponding to engine vibration can be performed by a mechanical system with a simple configuration without using a complicated electric circuit, so that the structure can be simplified.

Further, FIG. 2 shows a second embodiment in which the present invention is applied to an auxiliary air bleed for air-fuel ratio control in an engine 1 in which the air-fuel ratio is set to the lean side. A temporary main nozzle! 11 is a main fuel passage communicating with the main nozzle 50; 62 and 56;
are a main air bleed passage and an auxiliary air bleed passage provided in the main fuel passage 51, respectively. Also, 54
is a weight having a valve body 65 for opening and closing the atmosphere opening 65a of the auxiliary air bleed passage 56 to adjust the passage area of the auxiliary air bleed passage 65, and the weight S4 is integrated with the engine 1. The valve body 65 is elastically supported in the casing 56, the interior of which is open to the atmosphere, by elastic members 67 and 58 so as to be able to vibrate in the opening and closing direction (vibration direction of the engine 1), and when the engine vibrates. , the valve body 65 is closed by the inertia force of the weight 54 corresponding to the vibration of the engine 1, and the atmosphere opening port 5511L of the auxiliary air bleed passage 55 is closed, thereby reducing the passage area of the auxiliary air tube IJ)'' passage 660. Then, the amount of auxiliary airb IJ-)' is reduced, thereby enriching the air-fuel ratio and stabilizing the combustion state of the engine 1.

Furthermore, the weight 69 operates when the weight 64 operates in the valve opening direction of the valve body 55 (rightward in the figure), that is, in a direction that increases the amount of auxiliary air bleed and makes the combustion state of the engine 1 unstable. The delay device 59 is a delay device that delays the operation of the weight 54 when
9a, and a pressure chamber 59(i) defined by the diaphragm 59b and the diaphragm 591), and a spring 69θ compressed in the pressure chamber 59(i). A one-way valve 59f and an orifice 59g that allow atmospheric air to flow into the pressure chamber 59 (l) are arranged in parallel on the side wall of the valve 59d, and the weight 54 operates in the closing direction of the valve body 55 (leftward in the figure). Sometimes, the atmosphere is immediately introduced into the pressure chamber 59CL via the one-way valve 59f, and the rod 59a is moved by the biasing force of the spring 69θ.
follows the movement of the weight 54, while the weight 64
When the valve body 55 is operated in the valve opening direction (rightward in the figure), the pressure in the pressure chamber 59d, which becomes a positive pressure, is transferred to the orifice 59g.
The movement of the weight 64 against the urging force of the spring 59e by gradually releasing it into the atmosphere through the rod! It is configured to be slow due to the +9a regulation.

Therefore, in the second embodiment, when the engine vibrates, the weight! The valve element 55 closes due to the inertial force of the auxiliary air bleed passage 35, thereby closing the atmosphere opening port 5!1a of the auxiliary air bleed passage 35. As a result, the amount of auxiliary air bleed from the auxiliary air bleed passage 65 is reduced and metered to the main air bleed passage 65. nozzle! 10
Since the amount of fuel from the combustion engine 1 is increased and the air-fuel ratio of the engine 1, which is set on the lean side, is enriched, the combustion state of the engine 1 can be stabilized, and engine vibration can be suppressed. Also, weight 54
When the valve body 55 operates in a direction in which the combustion state of the engine 1 becomes unstable, the operation of the weight 64 can be delayed by the delay device 69 as in the first embodiment. Therefore, engine control corresponding to the engine vibration can be performed accurately without causing surging.

Further, FIG. 3 shows a third embodiment in which the present invention is applied to intake negative pressure as an operating source introduced into a vacuum advance type ignition advance device 40 that controls the advance of ignition timing, and 41 is Two ends communicate with a negative pressure outlet 42 that opens immediately upstream when the throttle valve 4 of the intake passage 2 is fully closed, and the other end communicates with a vacuum advance type ignition advance device 40 to operate the ignition advance device 40. This is a negative pressure introduction passage for introducing intake negative pressure as a source, and an atmosphere opening passage 45 branches from the middle of the negative pressure introduction passage 41, and is connected to the atmosphere opening 45a of the large kite opening passage 46. The valve body has the same structure as the second embodiment! A weight 64 with 15 and a delay device 59 are provided.

In this embodiment, when the engine vibrates, the weight 64
The inertia force causes the valve body 55 to close and open the atmosphere opening passage 46.
By closing the atmosphere opening port 45a of the ignition advance device 40, the amount of atmospheric dilution with respect to the intake negative pressure introduced into the ignition advance device 40 via the negative pressure introduction passage 41 is reduced.
The ignition timing is retarded by o, and the combustion state of the engine 1 does not shift to a stable state.Therefore, the engine vibration is suppressed without causing a surging phenomenon, and the engine control according to the engine vibration is performed appropriately. be able to.

Note that the present invention is not limited to the first to third embodiments described above, and may also be applied to various fluids that govern the combustion state of the engine, such as the amount of intake air in the bypass passage that bypasses the throttle valve 4 of the intake passage 2. It can also be applied to

As explained above, according to the present invention, it is possible to stabilize the combustion state of the engine during engine vibrations and suppress engine vibrations using a simple mechanical method. This can be carried out accurately without using the engine, simplify the structure, and prevent the engine control from surging, thereby improving accuracy.

[Brief explanation of drawings]

The drawings illustrate embodiments of the present invention; FIG. 1 is a schematic diagram showing the first embodiment, FIG. 2 is a schematic diagram showing the second embodiment, and FIG. 3 is a diagram showing the third embodiment. FIG. 1. Engine, 2. Intake passage, 4. Throttle valve, 5.
Exhaust gas recirculation passage, 6. Recirculation control valve, 7. Negative pressure introduction passage, 9. Exhaust gas recirculation device, 15. Atmospheric release passage, 16. Weight, 17. Valve body, 18.19.・Elastic member, 20. One-way valve, 21. Orifice, 22.
・Delay device! 15. Auxiliary air bleed passage, 64.
・Weight, 65...Valve body, 57.58...Elastic member,
69...Delay device, 40...Ignition advance device, 41...Negative pressure introduction passage, 46...Atmospheric release passage.

Claims (1)

[Claims] (1) The engine has a fluid passage for passing a fluid that controls the engine's combustion state, and a valve body for adjusting the passage area of the fluid passage, and is supported by the engine via an elastic member. A weight that measures the fluid by an inertial force corresponding to the vibration of the engine, and a delay device that delays the operation of the weight when the weight measures the fluid in a direction that makes the combustion state of the engine unstable. An engine control device characterized by: