CN106703928B - Exhaust valve control execution system directly driven by servo oil - Google Patents
Exhaust valve control execution system directly driven by servo oil Download PDFInfo
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- CN106703928B CN106703928B CN201611230647.9A CN201611230647A CN106703928B CN 106703928 B CN106703928 B CN 106703928B CN 201611230647 A CN201611230647 A CN 201611230647A CN 106703928 B CN106703928 B CN 106703928B
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- valve
- valve rod
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- exhaust valve
- pressure
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
- F01L9/00—Valve-gear or valve arrangements actuated non-mechanically
- F01L9/10—Valve-gear or valve arrangements actuated non-mechanically by fluid means, e.g. hydraulic
Abstract
A control execution system of an exhaust valve directly driven by servo oil is arranged on the exhaust valve comprising a valve rod and a valve shell and comprises a high-pressure common rail pipe, a driving execution unit and an air spring assembly; wherein, the air spring component is fixed on the top of the valve shell and connected with the valve rod; the driving execution unit is fixed at the top of the air spring assembly and is directly connected with the high-pressure common rail pipe and comprises an electromagnetic valve, a driving unit shell, a large piston, a small piston, a mechanical spring assembly and a one-way valve, wherein the electromagnetic valve is connected with the high-pressure common rail pipe; the driving execution unit directly controls and drives the valve rod to move up and down to open and close the exhaust valve by using high-pressure servo oil in the high-pressure common rail pipe. The invention realizes the control of the valve rod by adopting direct drive, and has the advantages of less error, simple structure, low cost, long service life and small impact.
Description
Technical Field
The invention relates to an electro-hydraulic drive control system for an exhaust valve of a marine high-power low-speed diesel engine, in particular to an exhaust valve control execution system directly driven by servo oil, and belongs to the technical field of diesel engines.
Background
The exhaust valve of the marine low-speed diesel engine and the control driving system thereof are one of the core components of the diesel engine, and the driving characteristics of the exhaust valve directly influence the economy and the emission performance of the engine. The electro-hydraulic drive control system for the exhaust valve widely used in the market at present is based on the principle of indirect drive, namely: servo oil is filled into a pressurizing cavity of the execution unit through a throttling hole or a one-way valve in a high-pressure or low-pressure mode, when the exhaust valve needs to be opened, the control unit sends an instruction to control the electromagnetic valve to be electrified, the high-pressure servo oil drives the pressurizing piston to move upwards to compress the servo oil in the pressurizing cavity, the compressed high-pressure servo oil is transmitted to the top end of the exhaust valve through a servo oil pipe to drive the exhaust valve rod to move downwards, and the exhaust valve is opened; when the exhaust valve is to be closed, the control unit sends an instruction to control the electromagnetic valve to be powered off, the high-pressure servo oil is cut off, the pressurizing piston moves downwards, the pressure of the servo oil in the pressurizing cavity is rapidly reduced, the exhaust valve rod moves upwards under the action of the air spring, and the exhaust valve is closed. Due to different working conditions, errors in machining and assembly, inconsistent oil supplement and leakage conditions of cylinders or accidental conditions of parts in each action process, the system can cause the stroke of the valve rod to not reach a preset value or even fail, so that the performance and the emission of the diesel engine are seriously influenced.
Disclosure of Invention
The invention aims to overcome the defects in the prior art, provides an exhaust valve control execution system directly driven by servo oil, simplifies the system composition, simultaneously realizes the opening and closing control of an exhaust valve rod, improves the exhaust and ventilation efficiency, and prolongs the service life of each component of the system.
In order to achieve the above object, the technical solution of the present invention is as follows:
an exhaust valve control execution system directly driven by servo oil is installed on an exhaust valve, the exhaust valve comprises a valve rod and a valve shell, and the exhaust valve control execution system is characterized by comprising a high-pressure common rail pipe for conveying the servo oil, a drive execution unit and an air spring assembly;
the air spring assembly is fixed at the top of the valve shell and is connected with the valve rod;
the driving execution unit is fixed at the top of the air spring assembly and is directly connected with the high-pressure common rail pipe, and comprises an electromagnetic valve, a driving unit shell, a large piston, a small piston, a mechanical spring assembly and a one-way valve, wherein the electromagnetic valve is arranged on the driving unit shell, is positioned at the uppermost part of the driving execution unit and is connected with the high-pressure common rail pipe, the driving unit shell is fixed on the air spring assembly and is provided with an upper throttling hole and a lower throttling hole from top to bottom, the one-way valve is connected to the lower throttling hole and is connected with the high-pressure common rail pipe, the mechanical spring assembly, the large piston and the small piston are sequentially arranged in the driving unit shell from top to bottom, and the small piston is pressed against the upper end of the valve rod;
The high-pressure common rail pipe is a multi-channel oil supply pipe and provides high-pressure driving pressure for the driving execution unit;
the driving execution unit directly controls and drives the valve rod to move up and down to open and close the exhaust valve by using high-pressure servo oil in the high-pressure common rail pipe.
Further, the stroke of the valve stem is determined by the height of the upper orifice and the lower orifice and can be finely adjusted by changing the height of the upper orifice and the lower orifice.
Further, the driving unit shell comprises two-stage cylindrical holes, and a hydraulic buffer groove is arranged on the bottom surface of the first-stage cylindrical hole to reduce the impact of the large piston on the driving unit shell when the valve rod is opened.
Further, the bottom of the large piston is provided with a groove to reduce the impact of the small piston on the large piston when the valve rod is closed.
Further, the top of the small piston is a conical surface so as to play a guiding role when the valve rod is closed, and the top of the small piston and the lower throttling hole jointly form a throttling effect in a valve rod maintaining stage; the throttle valve and the throttling effect act together to realize the self-adaption of the driving pressure of the small piston upper cavity under different loads in the valve rod maintaining stage, and the servo oil loss is reduced.
Compared with the prior art, the invention has the beneficial effects that:
1. the drive execution unit is directly connected with the high-pressure common rail pipe of the servo oil, and a directly-driven electro-hydraulic exhaust valve control system is adopted to replace a traditional electro-hydraulic control drive system which indirectly realizes the opening and closing of the valve rod through oil supplementing and pressurization; compared with an exhaust valve actuating mechanism driven indirectly, the invention reduces a set of oil supplementing and pressurizing components, not only simplifies the structure, but also can effectively avoid the phenomenon that the opening of the valve rod is inconsistent and even the exhaust valve cannot be opened due to inconsistent oil supplementing and leakage.
2. The servo oil high-pressure common rail pipe is directly connected with the driving execution unit, so that the pressure drop of the driving servo oil is effectively reduced, and the execution efficiency of the exhaust valve control execution system is improved.
3. The valve rod stroke of the exhaust valve control actuating system can be finely adjusted by changing the heights of the upper throttle hole and the lower throttle hole.
4. The buffer structure is adopted among all moving parts, so that hard collision can be effectively avoided, and the service life of the system is prolonged.
5. The invention effectively reduces the processing and assembling difficulty and greatly reduces the processing and manufacturing cost of the whole device.
Drawings
FIG. 1 is a schematic diagram of the present invention.
Fig. 2 is a schematic illustration of the valve stem opening process.
Fig. 3 is a schematic illustration of the valve stem closing process.
Fig. 4 is a schematic diagram of an extended application of the present invention.
In the figure:
the air spring type high-pressure common rail valve comprises a valve rod 1, a valve seat 2, a valve shell 3, a single damping valve 4, an air spring assembly 5, a one-way valve 6, an upper throttling hole 7, a lower throttling hole 8, a driving unit shell 9, a small piston 10, a large piston 11, a mechanical spring assembly 12, an electromagnetic valve 13 and a high-pressure common rail pipe 14.
Detailed Description
The exhaust valve control actuating system directly driven by servo oil according to the present invention will be further described in detail with reference to the accompanying drawings and specific embodiments, but the scope of the present invention should not be limited thereby.
Referring to fig. 1, a control and execution system of an exhaust valve directly driven by servo oil is shown installed on the exhaust valve, which includes a valve rod 1, a valve seat 2 and a valve housing 3; the exhaust valve control actuating system comprises a high-pressure common rail 14 for conveying servo oil, a driving actuating unit and an air spring assembly 5.
The air spring assembly 5 is fixed on the top of the valve housing 3 of the exhaust valve and connected with the valve rod 1, and the lower part of the air spring assembly 5 is provided with a single damping valve 4.
The driving execution unit is fixed on the top of the air spring assembly 5 and is directly connected with the high-pressure common rail pipe 14; the drive actuator unit comprises a solenoid valve 13, a drive unit housing 9, a large piston 11, a small piston 10, a mechanical spring assembly 12 and a one-way valve 6. The driving execution unit directly controls and drives the valve rod 1 to move up and down by using high-pressure servo oil in the high-pressure common rail pipe 14 so as to open and close the exhaust valve.
The electromagnetic valve 13 is a large-flow two-position two-way electromagnetic valve, is mounted on the driving unit shell 9, and controls the opening and closing of the valve rod 1 of the exhaust valve through power on and power off. The solenoid valve 13 is located at the uppermost portion of the driving performing unit and is connected to the high pressure common rail 14.
The driving unit shell 9 is fixed on the air spring assembly 5 and is provided with an upper throttling hole 7 and a lower throttling hole 8 from top to bottom; the check valve 6 is installed at the lower orifice 8 and connected with the high-pressure common rail pipe 14, and is used for preventing the servo oil in the oil return path from flowing back into the driving system.
The stroke of the valve rod 1 is determined by the heights of the upper orifice 7 and the lower orifice 8, and the stroke of the valve rod 1 can be finely adjusted by changing the heights of the upper orifice 7 and the lower orifice 8. The upper orifice 7 and the lower orifice 8 can reduce the driving oil pressure at the upper end of the small piston 10 to a pressure value required for maintaining a load when the small piston 10 moves to the stroke end, and reduce the consumption of the servo oil in the stroke maintaining stage of the valve rod 1,
The mechanical spring assembly 12, the large piston 11 and the small piston 10 are arranged in the driving unit housing 9 and are sequentially arranged from top to bottom; the small piston 10 is pressed against the upper end of the valve stem 1.
The top of the cylindrical surface of the small piston 10 is in a conical surface form so as to ensure the guiding function in the closing process of the valve rod 1, and simultaneously the conical surface and the lower throttling hole 8 provided with the one-way valve 6 jointly form a throttling effect in the maintaining stage of the valve rod 1; the one-way valve 6 and the throttling effect act together, so that the driving pressure of the upper cavity of the small piston can be self-adapted under different loads in the valve rod maintaining stage, and the servo oil loss is reduced.
The driving execution unit adopts various buffering modes, and can reduce the impact force between the moving parts.
The driving unit shell 9 comprises two-stage cylindrical holes for the conversion of driving force during the opening and maintaining processes of the valve rod 1; a hydraulic buffer groove is arranged on the bottom surface of the first-stage cylindrical hole and used for reducing the impact of the large piston 11 on the driving unit shell 9 when the valve rod 1 is opened.
The bottom of the large piston 11 is provided with a groove for reducing the impact force of the small piston 10 to the large piston 11 when the valve rod 1 is closed.
The mechanical spring assembly 12 can play a role of buffering when the valve rod 1 is closed.
The lower orifice 8 and the check valve 6 may serve to dampen and dampen pressure fluctuations.
The high-pressure common rail pipe 14 is a multi-channel oil supply pipe, is directly connected with the driving execution unit, provides stable high-pressure driving pressure for the driving execution unit, and collects return oil in a driving oil channel.
The invention adopts a directly driven electro-hydraulic control system to replace an electro-hydraulic control driving system which indirectly realizes the opening and closing of the valve rod 1 through oil supplement and pressurization. The specific working principle of the invention is as follows:
the exhaust valve venting process is shown in fig. 2. A control system (not shown in the figure) sends a control signal, an electromagnetic valve 13 is electrified, a path of high-pressure servo oil led out from a high-pressure common rail pipe 14 directly enters an upper cavity (position a in figure 2) of a large piston 11 of a driving execution unit through the electromagnetic valve 13, and pushes a small piston 10 and a valve rod 1 to overcome the back pressure of a cylinder and the resistance of an air spring assembly 5 so as to open an exhaust valve, and meanwhile, because the driving force is larger when the valve rod 1 is opened, a hydraulic buffer tank is arranged on a driving unit shell 9 in order to prevent the large piston 11 from directly impacting a driving unit shell 9; when the large piston 11 reaches the mechanical limit, the oil path on the driving unit housing 9 is opened, the high-pressure servo driving oil enters the upper chamber of the small piston 10 through the loop and the upper orifice 7 (position b in fig. 2), and continues to push the valve rod 1 to continue to open until the set stroke, meanwhile, when the small piston 10 drives the valve rod 1 to reach the set stroke value, the driving servo oil on the upper chamber of the small piston 10 is connected with the oil return path through the lower orifice 8 and the one-way valve 6 (position c in fig. 2), and due to the flow limiting effect formed among the upper orifice 7, the lower orifice 8, the conical surface of the small piston 10 and the driving unit housing 9, the driving servo oil pressure on the upper chamber of the small piston 10 can be maintained at a specific value, and the value can change along with the change of the load, so that the self-adaption is achieved.
The exhaust valve closing process is shown in fig. 3. A control system (not shown in the figure) sends a control signal, the electromagnetic valve 13 is de-energized, the valve rod 1 pushes the small piston 10 to move upwards under the residual pressure of the cylinder and the acting force of the air spring assembly 5, after the small distance is operated, the lower orifice 8 provided with the check valve 6 is completely shielded, the servo oil in the upper cavity of the small piston 10 returns to the upper cavity of the large piston 11 through the upper orifice 7 and is connected with an oil return channel in the high-pressure common rail pipe 14 through the electromagnetic valve 13 (position a in figure 3); when the servo oil in the upper cavity of the small piston 10 cannot be discharged from the upper orifice 7 in time, a certain pressure (determined by the pressure of the cylinder and the air spring when the exhaust valve is closed) is generated by the servo oil, the large piston 11 is pushed to move upwards, the oil return passages of the upper cavity of the small piston 10 and the upper cavity of the large piston 11 are cut off, a closed pressure cavity is formed between the small piston 10 and the large piston 11 until the position shown in the position b of fig. 3 is moved, the cavity is communicated with the oil return passage at the lower end of the large piston 11, and the servo oil directly returns to the common rail pipe through the oil return passage (the position c of fig. 3). The top of the large piston 11 is provided with a mechanical spring assembly 12, and the bottom of the large piston is in a groove form, so that the impact between the large piston 11 and the small piston 10, between the large piston 11 and a connecting block of the electromagnetic valve 13, and between the valve rod 1 and the valve seat 2 can be avoided, and the functions of buffering and inhibiting pressure fluctuation in the system can be realized.
Fig. 4 is one of the extended applications of the present invention. As shown in fig. 4, the opening process of the exhaust valve is completely the same as the above case, when the valve rod 1 is closed, there is no situation of cutting off the oil return passage at the upper orifice 7, that is, when the servo oil cannot be discharged from the upper orifice 7 in time, under the push of the air spring assembly 5 and the cylinder back pressure, the large piston 11 contacts and compresses the mechanical spring assembly 12 first, until the servo oil between the large piston 11 and the small piston 10 is completely discharged through the orifice, and the valve rod 1 and the valve seat 2 can have a buffering effect on the impact between the small piston 10 and the large piston 11, and between the valve rod 1 and the valve seat 2.
The above description is only a preferred embodiment of the present invention, and it should be noted that various equivalent modifications, changes and corrections made by those skilled in the art according to the content of the present application should be regarded as the protection scope of the present invention.
Claims (4)
1. An exhaust valve control execution system directly driven by servo oil is installed on an exhaust valve, and the exhaust valve comprises a valve rod and a valve shell;
the air spring assembly is fixed at the top of the valve shell and is connected with the valve rod;
The driving execution unit is fixed at the top of the air spring assembly and is directly connected with the high-pressure common rail pipe, and comprises an electromagnetic valve, a driving unit shell, a large piston, a small piston, a mechanical spring assembly and a one-way valve, wherein the electromagnetic valve is arranged on the driving unit shell, is positioned at the uppermost part of the driving execution unit and is connected with the high-pressure common rail pipe, the driving unit shell is fixed on the air spring assembly and is provided with an upper throttling hole and a lower throttling hole from top to bottom, the one-way valve is connected to the lower throttling hole and is connected with the high-pressure common rail pipe, the mechanical spring assembly, the large piston and the small piston are sequentially arranged in the driving unit shell from top to bottom, and the small piston is pressed against the upper end of the valve rod;
the high-pressure common rail pipe is a multi-channel oil supply pipe and provides high-pressure driving pressure for the driving execution unit;
the driving execution unit directly controls and drives the valve rod to move up and down to open and close the exhaust valve by using high-pressure servo oil in the high-pressure common rail pipe;
the stroke of the valve stem is determined by the height of the upper orifice and the lower orifice and can be finely adjusted by changing the height of the upper orifice and the lower orifice.
2. The servo oil directly driven exhaust valve control actuator system according to claim 1, wherein: the driving unit shell comprises two stages of cylindrical holes, and a hydraulic buffer groove is arranged on the bottom surface of the first stage of cylindrical hole so as to reduce the impact of the large piston on the driving unit shell when the valve rod is opened.
3. The servo oil directly driven exhaust valve control actuator system according to claim 1, wherein: the bottom of the large piston is provided with a groove to reduce the impact of the small piston on the large piston when the valve rod is closed.
4. The servo oil directly driven exhaust valve control actuator system according to claim 1, wherein: the top of the small piston is a conical surface so as to play a role in guiding when the valve rod is closed, and the top of the small piston and the lower throttling hole jointly form a throttling effect in a valve rod maintaining stage; the one-way valve and the throttling effect act together to realize the self-adaption of the driving pressure of the small piston upper cavity under different loads in the valve rod maintaining stage, and the servo oil loss is reduced.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201611230647.9A CN106703928B (en) | 2016-12-28 | 2016-12-28 | Exhaust valve control execution system directly driven by servo oil |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201611230647.9A CN106703928B (en) | 2016-12-28 | 2016-12-28 | Exhaust valve control execution system directly driven by servo oil |
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| CN106703928A CN106703928A (en) | 2017-05-24 |
| CN106703928B true CN106703928B (en) | 2022-07-15 |
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| CN201611230647.9A Active CN106703928B (en) | 2016-12-28 | 2016-12-28 | Exhaust valve control execution system directly driven by servo oil |
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Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107965605A (en) * | 2017-12-29 | 2018-04-27 | 中船动力研究院有限公司 | A kind of gerotor type air bleeding valve |
| CN109404363B (en) * | 2018-10-30 | 2020-09-15 | 中船动力研究院有限公司 | Hydraulic cylinder for driving exhaust valve and working method thereof |
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| CH503892A (en) * | 1969-08-30 | 1971-02-28 | Bosch Gmbh Robert | Control of inlet and outlet valves of internal combustion engines by liquid |
| DK126866B (en) * | 1971-02-26 | 1973-08-27 | Burmeister & Wains Mot Mask | Hydraulic drive system for periodically moving controls, in particular outflow valves for internal combustion engines. |
| US5193495A (en) * | 1991-07-16 | 1993-03-16 | Southwest Research Institute | Internal combustion engine valve control device |
| JP2870682B2 (en) * | 1993-11-02 | 1999-03-17 | 日鍛バルブ株式会社 | Hydraulic intake and exhaust valve drive with damper |
| CN1096538C (en) * | 2000-03-27 | 2002-12-18 | 武汉理工大学 | Electronically controlled hydraulically-driven common-pipe (tracl) air inlet and exhaustion system for IC engine |
| US6584885B2 (en) * | 2001-06-12 | 2003-07-01 | Visteon Global Technologies, Inc. | Variable lift actuator |
| DE10239747A1 (en) * | 2002-08-29 | 2004-03-11 | Robert Bosch Gmbh | Hydraulic valve actuator for actuating a gas exchange valve |
| US7536984B2 (en) * | 2007-04-16 | 2009-05-26 | Lgd Technology, Llc | Variable valve actuator with a pneumatic booster |
| CN101975098B (en) * | 2010-09-30 | 2012-12-19 | 哈尔滨工程大学 | Camless electrohydraulic variable valve timing system based on fuel medium |
| CN102913299A (en) * | 2012-10-09 | 2013-02-06 | 哈尔滨工程大学 | Air spring electromagnetically-driving valve mechanism of diesel engine |
| JP6092090B2 (en) * | 2013-12-25 | 2017-03-08 | 三菱重工業株式会社 | Exhaust valve driving device and internal combustion engine provided with the same |
| JP6038055B2 (en) * | 2014-01-10 | 2016-12-07 | 三菱重工業株式会社 | Exhaust valve driving device and internal combustion engine provided with the same |
| CN103953412B (en) * | 2014-03-21 | 2016-08-03 | 哈尔滨工程大学 | Classification booster-type air bleeding valve |
| CN103953411B (en) * | 2014-03-21 | 2016-06-29 | 哈尔滨工程大学 | Two-step supercharging valve exhaust gear |
| CN104088681B (en) * | 2014-04-04 | 2016-08-17 | 宁波华液机器制造有限公司 | Variable actuator |
| CN104632317A (en) * | 2015-01-30 | 2015-05-20 | 哈尔滨工程大学 | Vent valve device for high-power low-speed marine diesel engine |
| CN105485407A (en) * | 2015-12-29 | 2016-04-13 | 沪东重机有限公司 | Gas exhaust valve drive system with stroke capable of being compensated and regulated |
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