阅读说明：本技术 通过缸内制动控制降低发动机熄火过程抖动的控制系统及其控制方法 (Control system and control method for reducing engine flameout process jitter through in-cylinder brake control ) 是由 罗朝发 李文静 于 2019-11-29 设计创作，主要内容包括：本发明公开了一种通过缸内制动控制降低发动机熄火过程抖动的控制系统及其控制方法。该通过缸内制动控制降低发动机熄火过程抖动的控制系统包括：发动机,其具有多个气缸以及设置在各个气缸上的气门摇臂、排气门驱动桥、排气门；缸内制动器,其安装在所述排气门上,用于驱动排气门打开或关闭；缸内制动电磁阀,其与所述缸内制动器连接；以及电控单元,其与所述缸内制动电磁阀控制连接,能够根据发动机不同运行工况控制所述缸内制动电磁阀驱动缸内制动器打开或关闭排气门。该通过缸内制动控制降低发动机熄火过程抖动的控制系统及其控制方法抑制和消耗飞轮的转动能量,从而不会产生抖动、反转现象。(The invention discloses a control system and a control method for reducing engine flameout process jitter through in-cylinder brake control. The control system for reducing the shaking of the engine flameout process through the in-cylinder brake control comprises: an engine having a plurality of cylinders, and a valve rocker arm, an exhaust valve drive axle, and an exhaust valve provided on each cylinder; the cylinder brake is arranged on the exhaust valve and used for driving the exhaust valve to open or close; the in-cylinder brake electromagnetic valve is connected with the in-cylinder brake; and the electric control unit is in control connection with the in-cylinder brake solenoid valve and can control the in-cylinder brake solenoid valve to drive the in-cylinder brake to open or close the exhaust valve according to different running conditions of the engine. The control system and the control method thereof for reducing the shaking in the flameout process of the engine through in-cylinder brake control inhibit and consume the rotation energy of the flywheel, so that the shaking and reverse rotation phenomena can not be generated.)

1. A control system for reducing engine stall process judder through in-cylinder brake control, comprising:

an engine having a plurality of cylinders, and a valve rocker arm, an exhaust valve drive axle, and an exhaust valve provided on each cylinder;

the cylinder brake is arranged on the exhaust valve and used for driving the exhaust valve to open or close;

the in-cylinder brake electromagnetic valve is connected with the in-cylinder brake; and

and the electric control unit is in control connection with the in-cylinder braking electromagnetic valve and can control the in-cylinder braking electromagnetic valve to drive the in-cylinder brake to open or close the exhaust valve according to different running conditions of the engine.

2. The control system for reducing engine stall process jitter through in-cylinder braking control of claim 1, wherein the in-cylinder braking solenoid valve is disposed on the valve rocker arm or exhaust valve drive axle.

3. A control system for reducing engine misfire process jitter through in-cylinder brake control as recited in claim 1 wherein the intake end of the engine is provided with an engine intake manifold, a supercharger, a throttle valve and an air cleaner.

4. A control method of a control system for reducing the shake of an engine during the flameout process through in-cylinder brake control according to any one of claims 1 to 3, characterized in that during the flameout process, an in-cylinder brake solenoid valve is controlled by an electronic control unit to drive an in-cylinder brake to open an exhaust valve in advance during the compression and expansion strokes of the engine, so as to release the compressed gas in the cylinder, reduce the impact of the expansion work during the power stroke, and further reach the balance with the mechanical resistance during the flameout process of the engine to eliminate the vibration.

Technical Field

The invention relates to the field of engines, in particular to a control system and a control method for reducing engine flameout process jitter through in-cylinder brake control.

Background

At present, in the process of flameout and shutdown of a general diesel engine, the engine is reduced from the idle speed (generally 600r/min-900r/min) to 0r/min through the self friction resistance, and the larger the self friction resistance is, the shorter the shutdown time is. The rear end of the engine is generally provided with a flywheel, the flywheel has certain rotational inertia in the rotating process, the rotational inertia is related to the self weight of the flywheel and the rotating speed of the flywheel, and the heavier the flywheel is, the higher the rotating speed is, the larger the rotational inertia is generated by the flywheel. Through a large number of practices, the rotation of the flywheel still drives the engine to complete four work cycles of air suction, compression, work application and exhaust in the rear section (namely about 150r/min-0r/min) of flameout rotation speed reduction of the engine, in the work application process, although the engine does not inject oil, compressed high-pressure gas still applies work to a piston to generate thrust, the more fresh air is sucked in the air suction process, the greater expansion power is generated in the work application process, the greater the expansion power is, the greater the impact is generated in the flameout process, and the phenomena of vibration, shaking or resonance are generated in the flameout and shutdown processes of the engine and the whole vehicle, so that the comfort is influenced.

The information disclosed in this background section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.

Disclosure of Invention

The invention aims to provide a control system and a control method for reducing the shaking of an engine in the flameout process through in-cylinder brake control, which have simple and reasonable structure.

To achieve the above object, the present invention provides a control system for reducing engine stall jitter through in-cylinder brake control, comprising: an engine having a plurality of cylinders, and a valve rocker arm, an exhaust valve drive axle, and an exhaust valve provided on each cylinder; the cylinder brake is arranged on the exhaust valve and used for driving the exhaust valve to open or close; the in-cylinder brake electromagnetic valve is connected with the in-cylinder brake; and the electric control unit is in control connection with the in-cylinder brake solenoid valve and can control the in-cylinder brake solenoid valve to drive the in-cylinder brake to open or close the exhaust valve according to different running conditions of the engine.

In a preferred embodiment, an in-cylinder brake solenoid valve is provided on the rocker arm or the exhaust valve drive axle.

In a preferred embodiment, the air intake end of the engine is provided with an engine intake manifold, a supercharger, a throttle valve, and an air cleaner.

The invention also provides a control method of the control system for reducing the shake of the engine in the flameout process through in-cylinder brake control, in the flameout and shutdown process, the in-cylinder brake electromagnetic valve is controlled by the electric control unit to drive the in-cylinder brake to open the exhaust valve in advance in the compression and expansion strokes of the engine, so that the compressed gas in the cylinder is released, the impact of the expansion work in the working stroke is reduced, and the balance is further achieved with the mechanical resistance in the flameout and shutdown process of the engine to eliminate the vibration.

Compared with the prior art, the control system and the control method for reducing the engine flameout process jitter through in-cylinder brake control have the following beneficial effects: according to the control system and the control method for reducing the engine stalling process jitter through in-cylinder brake control, in the stalling and stopping process, the exhaust valve is opened through the in-cylinder brake in the compression and expansion strokes to reduce and release compressed gas in the cylinder, the impact of expansion work in the working stroke is reduced, and therefore the mechanical resistance in the engine stalling and stopping process is balanced to eliminate vibration.

Drawings

Fig. 1 is a schematic diagram of a control system for reducing engine stall process judder by in-cylinder brake control according to a first embodiment of the invention.

Detailed Description

The following detailed description of the present invention is provided in conjunction with the accompanying drawings, but it should be understood that the scope of the present invention is not limited to the specific embodiments.

Throughout the specification and claims, unless explicitly stated otherwise, the word "comprise", or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated element or component but not the exclusion of any other element or component.

The shake of the engine in the flameout process is caused by the fact that the gas compression and expansion work accelerates the rotation of the flywheel due to the action of highly compressed gas on the piston in the work stroke of the engine, and the rotating speed of the engine is reduced due to the action of mechanical resistance, so that the shake is caused by the imbalance of the gas expansion work and the mechanical resistance in the flameout process. The larger the work of gas expansion is, the larger the vibration is probably caused, and the work of gas expansion is related to the amount of fresh air sucked in the suction stroke of the engine or the amount of gas released in the compression stroke of the engine, and the more the gas enters the cylinder, the larger the work of expansion is.

To solve the above problems, as shown in fig. 1, a specific structure of a control system for reducing the judder during the engine stall through in-cylinder brake control according to a preferred embodiment of the present invention includes: the system comprises an engine 1, an electronic control unit 8, an in-cylinder brake electromagnetic valve and an in-cylinder brake 9. The compression and working strokes control the in-cylinder brake electromagnetic valve and the in-cylinder brake 9 through the electric control unit 8, so that the exhaust valve is closed later or the exhaust valve is opened in advance to release gas, the impact of expansion work of the working stroke is reduced, and the mechanical resistance in the flameout and shutdown processes of the engine is balanced to eliminate vibration.

Specifically, the engine 1 has a plurality of cylinders, and a rocker arm, an exhaust valve drive axle, and an exhaust valve provided in each cylinder, and the rocker arm drives the exhaust valve to open or close via the exhaust valve drive axle.

Preferably, an intake end of the engine 1 is provided with an engine intake manifold 4, a supercharger 5, a throttle valve 6, and an air cleaner 7.

An in-cylinder brake 9 is mounted on the exhaust valve for actuating the exhaust valve to open or close.

The in-cylinder brake electromagnetic valve is arranged on the valve rocker or the exhaust valve drive axle, is connected with the in-cylinder brake 9 and is used for driving the in-cylinder brake to control the exhaust valve to open or close.

The electric control unit 8 is connected with the in-cylinder brake solenoid valve in a control mode, opening and closing of the exhaust valve required under various working conditions can be flexibly controlled according to different running working conditions of the engine, in four working strokes of the engine, when the engine is in a compression stroke and an expansion stroke, the in-cylinder brake is opened through the solenoid valve, the exhaust valve is opened by one opening degree to release gas, and therefore high-pressure compressed gas cannot be formed in the opened cylinder of the exhaust valve of the expansion stroke engine, and expansion work cannot be performed.

The control method for reducing the engine stall process judder through in-cylinder brake control according to the preferred embodiment of the invention specifically includes: in the flameout and shutdown process, the electric control unit 8 controls the in-cylinder brake electromagnetic valve to drive the in-cylinder brake 9 to open the exhaust valve in advance in the compression and expansion strokes of the engine, so that the compressed gas in the cylinder is released, the impact of the expansion work in the working stroke is reduced, and the mechanical resistance in the flameout and shutdown process of the engine is balanced to eliminate vibration. Namely, the electronic control unit utilizes the exhaust valves of the compression stroke and the expansion stroke to open and release gas in the flameout and shutdown process of the engine, reduces the gas compression and expansion work, even negative expansion work, to inhibit and consume the rotation energy of the flywheel, does not do expansion work, and the operation performance of the engine is well balanced with the mechanical resistance, thereby avoiding the phenomena of shaking and reversion.

In conclusion, in the flameout and stop process of the control system and the control method thereof for reducing the engine flameout process jitter through the in-cylinder brake, the exhaust valve is opened through the in-cylinder brake in the compression and expansion stroke to reduce and release the compressed gas in the cylinder, so that the impact of the expansion work in the working stroke is reduced, and the mechanical resistance in the flameout and stop process of the engine is balanced to eliminate the vibration.

The foregoing descriptions of specific exemplary embodiments of the present invention have been presented for purposes of illustration and description. It is not intended to limit the invention to the precise form disclosed, and obviously many modifications and variations are possible in light of the above teaching. The exemplary embodiments were chosen and described in order to explain certain principles of the invention and its practical application to enable one skilled in the art to make and use various exemplary embodiments of the invention and various alternatives and modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the claims and their equivalents.