阅读说明：本技术 一种船用低速机喷油器针阀偶件 (Needle valve coupling part of oil sprayer of marine low-speed machine ) 是由 刘洋 张朝磊 林小雪 刘惠娥 张鹏 袁海军 梁小波 王庆利 易小龙 于 2021-09-04 设计创作，主要内容包括：本发明公开一种船用低速机喷油器针阀偶件,包括针阀体、针阀和喷嘴。喷嘴过盈连接在针阀体上,针阀从上至下依次设置配合导向面、密封锥面、密封环槽和配合密封面。针阀的配合导向面与配合密封面分别与针阀和喷嘴对应位置间隙配合。密封锥面与针阀的对应位置锥角配合。配合密封面开有汇流孔与导流孔。当针阀上升至限位时,导流孔与喷孔能完全连通。汇流孔、导流孔和喷孔与水平面的夹角依次减小。本发明可避免针阀高压密封座面与气缸燃烧环境直接接触,降低劣质燃油燃烧后产生的高温高冲击力及残留杂质对针阀高压密封座面的侵蚀；还可缓解滴油现象,提高燃油系统的使用寿命,改善高压燃油器紊流状况,使雾化过程受紊流影响减小。(The invention discloses a needle valve coupling part of a marine low-speed engine oil sprayer, which comprises a needle valve body, a needle valve and a nozzle. The nozzle is connected to the needle valve body in an interference mode, and the needle valve is sequentially provided with a matching guide surface, a sealing conical surface, a sealing ring groove and a matching sealing surface from top to bottom. The matching guide surface and the matching sealing surface of the needle valve are in clearance fit with the corresponding positions of the needle valve and the nozzle respectively. The sealing conical surface is matched with the conical angle of the needle valve at the corresponding position. The matching sealing surface is provided with a converging hole and a flow guide hole. When the needle valve rises to the limit, the guide hole and the spray hole can be completely communicated. The included angles between the confluence hole, the diversion hole and the spray hole and the horizontal plane are reduced in sequence. The invention can avoid the direct contact between the high-pressure sealing seat surface of the needle valve and the combustion environment of the cylinder, and reduce the corrosion of high-temperature high impact force and residual impurities generated after the combustion of inferior fuel oil to the high-pressure sealing seat surface of the needle valve; the oil dripping phenomenon can be relieved, the service life of a fuel system is prolonged, the turbulent flow condition of a high-pressure fuel oil device is improved, and the influence of the turbulent flow on the atomization process is reduced.)

1. A needle valve coupling part of a marine low-speed engine fuel injector comprises a needle valve body (1), a needle valve (3) and a nozzle (4); the nozzle (4) is connected to the needle valve body (1) in an interference manner, and the front end of the nozzle is provided with a spray hole (102); the needle valve (3) is arranged in the needle valve body (1) and the nozzle (4);

the method is characterized in that: needle valve (3) are from last to setting gradually cooperation spigot surface (105), sealed conical surface (107) and the sealed face of cooperation (109) down, cooperation spigot surface (105) correspond position clearance fit with needle valve body (1) and nozzle (4) respectively with the sealed face of cooperation (109), the cooperation of the corresponding position cone angle of sealed conical surface (107) and needle valve body (1), the both ends of the sealed face of cooperation (109) still open have multichannel sealed annular (108) to carry out supplementary seal, needle valve (3) are processed on the face of the cooperation of leading to have logical oil groove (106), and needle valve body (1) between form the passageway that leads to oil, utilize the fit clearance of fitting face to seal, form the slide valve structure.

2. The marine low speed engine fuel injector needle valve train as defined in claim 1, wherein: the nozzle (4) is elongate and the mating sealing surface (109) is a clearance fit with a corresponding location in the nozzle (4).

3. The needle valve coupler of the marine low-speed engine fuel injector according to claim 1 or 2, characterized in that: needle valve (3) are in open the one side top of the sealed face of cooperation (109) orifice (102) dorsad has one and converges hole (111), and the orifice of hole (111) and the ring cavity intercommunication that the sealed face of cooperation (109) surrounded by needle valve (3) and nozzle (4) converge, the sealed face of cooperation (109) is opened towards one side of orifice (102) and is had water conservancy diversion hole (110) that quantity and orifice (102) quantity equal, water conservancy diversion hole (111) and water conservancy diversion hole (110) communicate in the needle valve, form water conservancy diversion formula structure, the contained angle that converges hole (111), water conservancy diversion hole (110) and orifice (102) and horizontal plane reduces in proper order, when needle valve (3) rise to spacing, water conservancy diversion hole (110) and orifice (102) can communicate completely.

4. The needle valve coupler of the marine low-speed engine fuel injector according to claims 1 and 2, characterized in that: the spray orifices (102) of the nozzles (4) are arranged on the same side.

5. The needle valve coupler of the marine low-speed engine fuel injector according to claims 1 and 2, characterized in that: have horizontal directional hole (104) on needle valve (3), directional round pin (2) cross directional hole (104), orientation groove (101) on needle valve body (1) are brought into to both ends, are right needle valve (3) are fixed a position.

6. The needle valve coupler of the marine low-speed engine fuel injector according to claims 1 and 2, characterized in that: the nozzle (4) is made of a material which is corrosion-resistant, heat-resistant and small in thermal expansion coefficient.

Technical Field

The invention relates to the technical field of marine fuel systems, in particular to a needle valve coupling part for a low-speed engine oil sprayer.

Background

For the shipping industry, it has been difficult to reduce the cost of refined fuel. Therefore, low-speed and high-power diesel engines which are applicable to poor-quality fuel and have better economical efficiency are more and more favored by the ocean shipping industry. However, poor fuel oil has the disadvantages of complex components, more impurities, easy generation of solid particles and viscous liquid drops after combustion, and the like, if a seal seat surface of a needle valve, which is a key part in an oil injector, is in contact with waste gas after heavy oil is combusted for a long time, the seal seat surface is adhered by viscous or solid particles, the sealing performance of the needle valve is adversely affected, and meanwhile, the service life of the needle valve is further shortened due to high-temperature and high-impact force of fuel gas during combustion in a cylinder. Therefore, how to solve this problem is an important issue to improve the service life of the marine low-speed diesel engine.

In the prior art, the negative effects caused by impurities after combustion and high-temperature high impact are reduced by increasing an oil injection nozzle to ensure that a sealing seat surface of a needle valve is far away from a combustion environment from the distance. However, the nozzle length increases with the increase in nozzle bore length, resulting in an increase in bore volume. After the sealing seat surface of the needle valve is closed, the residual oil quantity of the inner hole of the nozzle is increased, meanwhile, the oil pressure in the nozzle is rapidly reduced, the oil dripping phenomenon can be caused, the fuel oil atomization is poor, the combustion is easy to be incomplete, the emission of waste gas pollutants can be increased, even coking can be caused in a cylinder in severe cases, and the service life of a fuel oil system is shortened. In addition, the method of increasing the oil injection nozzle makes the shape of the inner cavity of the nozzle difficult to be considered in design, and if the fuel suddenly flows towards the front end of the spray hole at a large angle or suddenly flows through a cavity with a large volume, great turbulence can be formed, and the oil injection and atomization effects are affected. Therefore, the needle valve coupling part of the low-speed engine fuel injector still has the possibility of further improvement.

Disclosure of Invention

The invention provides a needle valve coupling part of a low-speed diesel engine fuel injector, which aims to overcome the defects of the prior art, adopts a slide valve flow guide type structure, is applied to the low-speed diesel engine fuel injector with fuel injection oil holes arranged on the same side and a severe combustion environment, and aims to prevent the high-pressure sealing seat surface of the needle valve from being in direct contact with the combustion environment of a cylinder, reduce the high-temperature high impact force generated after combustion of inferior fuel oil and the corrosion of residual impurities on the high-pressure sealing seat surface of the needle valve, further improve the turbulence condition of a high-pressure fuel injector, reduce the influence of the turbulence on the atomization process, reduce the oil dripping phenomenon and relieve the influence of insufficient combustion of unadulterated oil drops on the service life of an oil system.

The technical scheme of the invention is as follows:

the invention provides a slide valve diversion type marine low-speed engine fuel injector needle valve matching part which comprises a needle valve body, a needle valve and a nozzle. The nozzle is connected to the needle valve body in an interference mode, and an oil injection hole is formed in the nozzle. The needle valve is installed in the needle valve body and the nozzle.

The invention improves the sealing structure of the needle valve, the sealing structure sequentially comprises a matching guide surface, a sealing conical surface and a matching sealing surface from top to bottom, the matching guide surface and the matching sealing surface are respectively in clearance fit with corresponding positions of the needle valve body and the nozzle, the sealing conical surface is matched with a conical angle of the corresponding position of the needle valve body, and a plurality of sealing ring grooves are formed in two ends of the matching sealing surface for auxiliary sealing. The needle valve is characterized in that an oil through groove is machined on a guide matching surface, an oil through channel is formed between the needle valve and the needle valve body, and a matching gap of the matching surface is used for sealing to form a sliding valve structure.

Further, the nozzle is elongated and the mating sealing surface is clearance fit with a corresponding location inside the nozzle.

Furthermore, one side of the matching sealing surface, which is back to the spray hole, is provided with a confluence hole, and an opening of the confluence hole is communicated with the annular cavity above the matching sealing surface. One side of the matched sealing surface facing the spray hole is provided with a flow guide hole, and the confluence hole is communicated with the flow guide hole in the needle valve to form a flow guide structure. The number of the diversion holes is equal to the number of the jet holes. When the needle valve rises to the limit, the guide hole and the spray hole can be completely communicated. The distribution position and the length of each flow guide hole are different with different spray holes. The included angles between the confluence hole, the diversion hole and the spray hole and the horizontal plane are reduced in sequence.

By adopting the improved technical scheme, the invention has the following beneficial technical effects:

1. the invention adopts a slide valve flow guiding structure, an oil through groove of the valve is arranged on a guide matching surface, the sealing is carried out by utilizing the small gap of the guide matching surface, and the needle valve is provided with the flow guiding structure consisting of the converging hole and the flow guiding hole, thereby ensuring the sealing property, avoiding the erosion of the high-pressure sealing seat surface of the needle valve and improving the turbulent condition of a high-pressure fuel burner.

2. The length of the nozzle and the matching seal of the needle valve can prevent the high-pressure seal seat surface of the needle valve from directly contacting with the combustion environment of the cylinder, reduce the high-temperature high impact force generated after the inferior fuel oil is combusted and the corrosion of residual impurities to the high-pressure seal seat surface of the needle valve, and the slender nozzle can save the installation space.

3. Through the structural design of the nozzle and the needle valve in matched sealing and the sealing ring groove, the oil dripping phenomenon caused by the outflow of residual oil in the nozzle can be relieved, the insufficient combustion of unadulterated oil drops is further relieved, and the service life of a fuel oil system is prolonged.

4. The included angles of the converging hole, the flow guide hole and the spray hole and the horizontal plane are sequentially reduced, namely the included angles of the plurality of oil holes and the spray holes and the horizontal plane are sequentially reduced, so that the deflection of the flow angle of the high-pressure fuel oil is gradually changed from steep to flat in the process of flowing through the oil holes, and the fuel oil cannot flow to or enter a large-size cavity at the front end of the spray hole in a large-angle sudden change manner to generate flow sudden change. Thereby improving the turbulent flow condition of the high-pressure fuel device and reducing the influence of the turbulent flow on the atomization process.

Drawings

FIG. 1 is a schematic structural view of the present invention;

FIG. 2 is a schematic view of a structure in which a needle valve is provided;

FIG. 3 is a schematic view of the installation position of the orientation pin of the present invention;

FIG. 4 is a schematic view of the invention in operation with the needle seated;

FIG. 5 is a schematic diagram of the invention operating with the needle valve lifted.

The automatic sealing device comprises a 1-needle valve body, a 2-orientation pin, a 3-needle valve, a 4-nozzle, a 101-orientation groove, a 102-spray hole, a 103-spring seat, a 104-orientation hole, a 105-matching guide surface, a 106-oil through groove, a 107-sealing conical surface, a 108-sealing ring groove, a 109-matching sealing surface, a 110-flow guide hole and a 111-confluence hole.

Detailed Description

Exemplary embodiments of the present invention are described in more detail below with further reference to the accompanying drawings. While exemplary embodiments of the present invention are shown in the drawings, it should be understood that the present method may be embodied in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

Referring to fig. 1, the needle valve coupling of the slide valve diversion type marine low-speed engine fuel injector disclosed by the embodiment comprises a needle valve body (1), a directional pin (2), a needle valve (3) and a nozzle (4). Wherein the nozzle (4) is connected to the front end of the needle valve body (1) in an interference manner, the nozzle (4) is in a long and thin shape, and one side of the front end of the nozzle is provided with a spray hole (102) which is communicated with the inside and the outside of the nozzle (4). The needle valve (3) is also of an elongated shape, the upper part of which is arranged in the needle valve body (1) and the lower part of which is arranged in the nozzle (4).

As shown in fig. 2, in this embodiment, the structure of the needle valve (3) is improved, and the structure of the needle valve (3) from top to bottom is: the oil seal structure comprises a spring seat (103), a matching guide surface (105), an oil through groove (106), a sealing conical surface (107), a sealing ring groove (108) and a matching sealing surface (109). Wherein:

the spring seat (103) is used for installing a spring, and the matching guide surface (105) is in clearance fit with the corresponding position of the needle valve body (1) and has a guiding function.

The oil through groove (106) is a straight groove which is processed on the guide matching surface of the needle valve (3) and the needle valve body (1), and an oil through channel is formed between the straight groove and the needle valve body (1).

The sealing conical surface (107) is matched with the conical angle of the corresponding position of the needle valve (3), and is opened when the needle valve (3) is lifted and closed when the needle valve is dropped.

The matching sealing surface (109) is in clearance fit with the corresponding position inside the nozzle, so that the high-pressure sealing seat surface of the needle valve is prevented from being in direct contact with the combustion environment of the cylinder, and the corrosion of high-temperature high-impact force and residual impurities generated after the inferior fuel oil is combusted on the high-pressure sealing seat surface of the needle valve is reduced.

The matching sealing surface (109) is provided with a confluence hole (111) above one side back to the spray hole (102), and the orifice of the confluence hole (111) is communicated with an annular cavity which is surrounded by the needle valve (3) and the nozzle (4) above the matching sealing surface (109). The matching sealing surface (109) is provided with a flow guide hole (110) on one side facing the spray hole (102), and the confluence hole (111) is communicated with the flow guide hole (110) in the needle valve. The number of the diversion holes (110) is equal to that of the spray holes (102). When the needle valve (3) rises to the limit, the guide hole (110) and the spray hole (102) can be completely communicated. The distribution position and the length of each flow guide hole (110) are different with different spray holes (102). The included angles between the convergence hole (111), the flow guide hole (110) and the spray hole (102) and the horizontal plane are reduced in sequence.

In a further embodiment, as can be seen in fig. 3, the needle valve (3) is further provided with a transverse orientation hole (104) for allowing an orientation pin (2) to pass through and be received at both ends in an orientation groove (101) of the needle valve body (1), so that the needle valve (3) is prevented from deflecting during operation.

Referring to fig. 4 and 5, the working principle of the needle valve coupling member of the present embodiment is described as follows:

before oil injection is started, the needle valve (3) is under the action of spring force arranged on a spring seat (103), a sealing conical surface (107) of the needle valve (3) is attached to the corresponding position of the needle valve (3) by matching with hydraulic pressure, and high-pressure fuel to be injected is accumulated above the sealing conical surface (107) through an oil through groove (106) from an oil inlet end.

When the fuel injector starts to work, the hydraulic environment of fuel is changed through the control end, the needle valve (3) moves upwards under the influence of the supporting force provided by the matching guide matching surface (105) and axial hydraulic force, the sealing conical surface (107) is opened, and high-pressure fuel flows into an annular cavity of the nozzle (4) from the upper part of the sealing conical surface (107) and enters the confluence hole (111). Meanwhile, the needle valve (3) drives the matched sealing surface (109) to move upwards, and the guide hole (110) moves upwards and is communicated with the spray hole (102). The high-pressure fuel oil sequentially passes through the confluence hole (111) and the diversion hole (110), and is finally sprayed into the cylinder from the spray hole (102) for atomized combustion. Because of the large flow rate jump of the high-pressure fuel when it flows out of the sealing cone surface (107), the high-pressure fuel flows into the confluence hole (111) from the annular cavity in different directions in the nozzle (4), and therefore is in a turbulent state. Because the direction of the confluence hole (111) is fixed, the fuel in a turbulent state is preliminarily smoothed in the process of flowing along the confluence hole (111). The included angles of the confluence hole (111), the diversion hole (110) and the spray hole (102) with the horizontal plane are reduced in sequence. The deflection of the flow angle of the high-pressure fuel in the process of flowing through the three holes is changed from steep to flat, and the high-pressure fuel does not flow towards the front end of the jet hole (102) in a large-angle sudden change mode or flow sudden change caused by passing through a large-size chamber is avoided. Therefore, the turbulence condition of the high-pressure fuel device flowing into the spray hole (102) is improved, and the atomization process is influenced by the turbulence to be reduced.

When the work of the fuel injector is finished, the control end stops controlling to recover the fuel hydraulic environment, the needle valve (3) is seated under the action of spring force, the sealing conical surface (107) is compressed again, and high-pressure fuel is sealed on the sealing seat surface. Because the needle valve (3) and the nozzle (4) are in small clearance fit through the matching sealing surface (109), and in addition, the two ends of the matching sealing surface (109) are provided with a plurality of sealing ring grooves (108) for auxiliary sealing. Therefore, the residual fuel oil retained in the oil cavity of the nozzle (4) cannot flow to the spray hole (102) under the sealing action, and the oil injection process is stopped. At the moment, the gas in the cylinder can only contact with the matching sealing surface (109) through the spray hole (102) and cannot contact with the sealing conical surface (107), so that the corrosion of high-temperature high-impact force and residual impurities generated after poor fuel oil is combusted on the high-pressure sealing seat surface of the needle valve is reduced. Meanwhile, the length of the nozzle can prevent the high-pressure sealing seat surface of the needle valve from being in direct contact with the combustion environment of the cylinder, and the nozzle is slender, so that the required installation space is small, the installation space of the wall top of the cylinder is saved, and a space is provided for arrangement of a cooling oil duct and the like. Through the matching seal of the nozzle and the needle valve and the seal ring groove, the oil dripping phenomenon caused by the outflow of residual oil in the nozzle is relieved, the insufficient combustion of the unomized oil drops is further relieved, and the service life of a fuel oil system is prolonged.

The nozzle body of the nozzle for the needle valve matching part is made of corrosion-resistant and heat-resistant materials with small thermal expansion coefficient. Thus, thermal deformation caused by heating of the nozzle body can be reduced, the gap width of the matching sealing surface (109) is stable, and stable operation is ensured.

The embodiments described above describe only some of the one or more embodiments of the present invention, but those skilled in the art will recognize that the invention can be embodied in many other forms without departing from the spirit or scope thereof. Accordingly, the present examples and embodiments are to be considered as illustrative and not restrictive, and various modifications and substitutions may be made therein without departing from the spirit and scope of the present invention as defined by the appended claims.