阅读说明：本技术 一种包含强滚流预燃室的汽油机点火机构 (Gasoline engine ignition mechanism containing strong tumble precombustion chamber ) 是由 裴毅强 陈涛 安彦召 赵德阳 张帆 秦静 于 2021-08-18 设计创作，主要内容包括：本发明涉及一种包含强滚流预燃室的汽油机点火机构。点火机构包括：圆柱状的连接件,喷油器安装孔,火花塞安装孔,通过螺纹与连接件外周面相连接的预燃室,与喷油器安装孔配合工作的预燃室喷油器,与火花塞安装孔配合工作的预燃室火花塞；所述预燃室由三段组合而成,从上至下依次是第一圆柱套体、圆锥状套体和第二圆柱腔体；第二圆柱腔体下部有N个均匀分布的喷孔,N≥3；喷孔中至少有1个为倾斜喷孔,至少1个为径向喷孔；本发明在压缩行程中缸内气流通过预燃室喷孔直接流向预燃烧室的上部,受缸内气流运动的影响,当气流到达预室上壁时会发生侧向偏转,在预室内形成滚流,从而促进预燃室内火焰的发展和传播。(The invention relates to a gasoline engine ignition mechanism comprising a strong tumble precombustion chamber. The ignition mechanism includes: the fuel injector comprises a cylindrical connecting piece, a fuel injector mounting hole, a spark plug mounting hole, a precombustion chamber connected with the peripheral surface of the connecting piece through threads, a precombustion chamber fuel injector matched with the fuel injector mounting hole for working, and a precombustion chamber spark plug matched with the spark plug mounting hole for working; the precombustion chamber is formed by combining three sections, namely a first cylindrical sleeve body, a conical sleeve body and a second cylindrical cavity body from top to bottom in sequence; the lower part of the second cylindrical cavity is provided with N spray holes which are uniformly distributed, wherein N is more than or equal to 3; at least 1 of the jet holes is an inclined jet hole, and at least 1 of the jet holes is a radial jet hole; in the compression stroke, the airflow in the cylinder directly flows to the upper part of the pre-combustion chamber through the jet holes of the pre-combustion chamber, is influenced by the movement of the airflow in the cylinder, and can be deflected laterally when reaching the upper wall of the pre-combustion chamber to form a tumble flow in the pre-combustion chamber, so that the development and the propagation of flame in the pre-combustion chamber are promoted.)

1. A gasoline engine ignition mechanism comprising a strong tumble pre-combustion chamber is characterized by comprising a cylindrical connecting piece (1), an oil sprayer mounting hole penetrating through the upper end surface and the lower end surface of the connecting piece, a spark plug mounting hole penetrating through the upper end surface and the lower end surface of the connecting piece, a pre-combustion chamber (5) connected with the peripheral surface of the connecting piece through threads, a pre-combustion chamber oil sprayer (4) working in cooperation with the oil sprayer mounting hole, and a pre-combustion chamber spark plug (2) working in cooperation with the spark plug mounting hole;

the precombustion chamber is formed by combining three sections, namely a first cylindrical sleeve body (10), a conical sleeve body (11) and a second cylindrical cavity body (12) from top to bottom in sequence, wherein the inner diameter of the first cylindrical sleeve body is fixedly connected with the outer circumferential surface of the connecting piece through threads, the inner diameter of the second cylindrical cavity body is smaller than that of the first cylindrical sleeve body, and the conical sleeve body is just connected with the first cylindrical sleeve body and the second cylindrical cavity body; the lower end surface of the connecting piece, the inner wall of the conical sleeve body and the inner wall of the second cylindrical cavity enclose to form a pre-combustion chamber;

the lower part of the second cylindrical cavity is provided with N spray holes which are uniformly distributed, and N is more than or equal to 3; all the spray holes are round straight holes, and the central lines of the spray holes are diffused outwards and obliquely downwards relative to the bottom surface of the second cylindrical cavity;

at least 1 of the jet holes is an inclined jet hole (8), and at least 1 of the jet holes is a radial jet hole (9); the central line of the inclined spray hole is not intersected, parallel and perpendicular to the central line of the second cylindrical cavity; the radial spray holes and the central line of the second cylindrical cavity are intersected in the precombustion chamber.

2. The ignition mechanism of a gasoline engine comprising a high tumble jet orifice prechamber according to claim 1 characterized in that said N has a value of 6, of which 4 are inclined orifices and 2 are radial orifices (9);

the inclined spray holes are symmetrically distributed along the X plane, and 2 spray holes are respectively arranged on two sides of the inclined spray holes; the central lines of the radial spray holes are all located in an X plane.

3. The ignition mechanism of a gasoline engine comprising a pre-combustion chamber with strong tumble jet orifice of claim 2, characterized in that the included angles and distances between the central line of all the oblique jet orifices and the central line of the second cylindrical cavity are equal; the included angles of the central lines of all the radial spray holes and the central line of the second cylindrical cavity are equal.

The technical field is as follows:

the invention relates to an ignition mechanism of an internal combustion engine, in particular to an ignition mechanism of a gasoline engine comprising a strong tumble precombustion chamber.

Background art:

the improvement of effective thermal efficiency is the future development direction of the engine under the requirement of oil consumption regulation. The combustion speed is accelerated, the isochoric degree is improved, and meanwhile, knocking is inhibited, so that the effective means for improving the heat-work conversion efficiency of the gasoline engine is provided.

The jet orifice arrangement of the precombustion chamber has a non-negligible influence on the development of internal flow and has an important influence on the combustion performance of the precombustion chamber. The prechamber orifice arrangement is generally a circumferential array. The inclined jet holes can reduce the turbulent kinetic energy requirement of jet flame of the precombustion chamber on the main combustion chamber, but the inclined jet holes enable the strength of vortex formed at the upper part of the precombustion chamber to be weaker in the compression stroke, so that the development and the propagation of flame in the precombustion chamber are influenced.

The invention content is as follows:

the invention aims to provide a strong tumble structure in a precombustion chamber, which solves the problems of insufficient local turbulence intensity, poor combustion performance and the like in the conventional precombustion chamber structure. In order to solve the above problems, the present invention provides the following technical solutions:

a gasoline engine ignition mechanism incorporating a strong tumble prechamber comprising: the fuel injector comprises a cylindrical connecting piece 1, fuel injector mounting holes penetrating through the upper end face and the lower end face of the connecting piece, spark plug mounting holes penetrating through the upper end face and the lower end face of the connecting piece, a prechamber 5 connected with the peripheral face of the connecting piece through threads, a prechamber fuel injector 4 matched with the fuel injector mounting holes to work, and a prechamber spark plug 2 matched with the spark plug mounting holes to work;

the precombustion chamber is formed by combining three sections, namely a first cylindrical sleeve body 10, a conical sleeve body 11 and a second cylindrical cavity body 12 from top to bottom in sequence, wherein the inner diameter of the first cylindrical sleeve body is fixedly connected with the outer circumferential surface of the connecting piece through threads, the inner diameter of the second cylindrical cavity body is smaller than that of the first cylindrical sleeve body, and the conical sleeve body is just connected with the first cylindrical sleeve body and the second cylindrical cavity body; the lower end surface of the connecting piece, the inner wall of the conical sleeve body and the inner wall of the second cylindrical cavity enclose to form a pre-combustion chamber; the center line of the spark plug mounting hole and the center line of the second cylindrical cavity are intersected in the second cylindrical cavity, and a plane formed by the intersection of the center line of the spark plug mounting hole and the center line of the second cylindrical cavity is defined as an X plane;

the lower part of the second cylindrical cavity is provided with N spray holes which are uniformly distributed, and N is more than or equal to 3; all the spray holes are round straight holes, and the central lines of the spray holes are obliquely downward diffused outwards relative to the bottom surface of the second cylindrical cavity;

at least 1 of the jet holes is an inclined jet hole 8, and at least 1 of the jet holes is a radial jet hole 9; the central line of the inclined spray hole is not intersected, parallel and perpendicular to the central line of the second cylindrical cavity; the radial spray holes and the central line of the second cylindrical cavity are intersected in the precombustion chamber.

In a first preferred embodiment, the number of N is 6, 4 of N are inclined nozzles, and 2 are radial nozzles 9; the inclined spray holes are symmetrically distributed along the X plane, and 2 spray holes are respectively arranged on two sides of the inclined spray holes; the central lines of the radial spray holes are all located in an X plane.

In the preferred scheme II, the included angles and the distances between the central lines of all the inclined jet holes and the central line of the second cylindrical cavity are equal; the included angles of the central lines of all the radial spray holes and the central line of the second cylindrical cavity are equal.

Compared with the prior art, the invention has the advantages that:

compared with the structure of the pre-combustion chamber with the inclined jet holes arranged in a circumferential array, the jet flame generated by adopting the radial jet holes has lower influence on the disturbance of mixed gas in the main combustion chamber than the inclined jet holes, but in a compression stroke, the air flow in the cylinder directly flows to the upper part of the pre-combustion chamber through the jet holes of the pre-combustion chamber, and under the influence of the motion of the air flow in the cylinder, the air flow can be deflected laterally when reaching the upper wall of the pre-combustion chamber, and a tumble flow is formed in the pre-combustion chamber, so that the development and the propagation of the flame in the pre-combustion chamber are promoted. The higher velocity heat jets produced by the precombustion chamber combustion result in greater turbulence and multiple flame fronts, resulting in faster combustion in the main combustion chamber.

And secondly, compared with a radial spray hole precombustion chamber structure which is circumferentially arranged in an array, the invention not only can exert the advantage of improving the turbulence of the main combustion chamber by the flame jet of the inclined spray hole, but also can provide stronger airflow motion for the ignition and combustion stage in the precombustion chamber in the compression process in the cylinder so as to promote the development of flame in the precombustion chamber by utilizing the characteristics of the tumble scavenging in the cylinder and only by configuring the inclined spray hole at a reasonable position in the precombustion chamber.

In the embodiment, the jet flow flame speed can be increased, the combustion performance of a main combustion chamber is improved, the lean burn limit is expanded, and the heat efficiency of an engine is improved.

Description of the drawings:

FIG. 1 is a schematic assembly view of an ignition mechanism for a gasoline engine incorporating a strong tumble prechamber according to the present invention; in the figure, 1 denotes a connecting member, 2 denotes a prechamber plug, 3 denotes a prechamber plug gasket, 4 denotes a prechamber injector, 5 denotes a prechamber, 6 denotes a sealing gasket, 7 denotes a prechamber plug electrode, 8 denotes an inclined nozzle hole, 10 denotes a first cylindrical sleeve, 11 denotes a conical sleeve, and 12 denotes a second cylindrical cavity.

FIG. 2 is a schematic structural diagram of an ignition mechanism in the embodiment after being matched with a cylinder; in the figure, an ignition mechanism is installed on the upper part of a main combustion chamber in an offset manner; 5 for the prechamber, 13 for the main combustion chamber of the engine, 14 for the engine cylinder and 15 for the engine piston.

FIG. 3 is an enlarged partial view of the prechamber of FIG. 2; in the figure, 8 denotes inclined orifices and 9 denotes radial orifices.

FIG. 4 is a schematic view of the nozzle holes of the prechamber of FIG. 3 as viewed along the direction A-A; in the figure, 8 represents inclined orifices and 9 represents radial orifices; the direction of the in-cylinder air flow in the figure better explains the tumble motion of the gas in the engine cylinder during the compression stroke, creating a more intense tumble motion inside the pre-combustion chamber.

The specific implementation mode is as follows:

example (b):

referring to FIGS. 1-4, embodiments of the present invention are illustrated.

A gasoline engine ignition mechanism incorporating a strong tumble prechamber comprising: the fuel injector comprises a cylindrical connecting piece 1, fuel injector mounting holes penetrating through the upper end face and the lower end face of the connecting piece, spark plug mounting holes penetrating through the upper end face and the lower end face of the connecting piece, a prechamber 5 connected with the peripheral face of the connecting piece through threads, a prechamber fuel injector 4 matched with the fuel injector mounting holes to work, and a prechamber spark plug 2 matched with the spark plug mounting holes to work;

the precombustion chamber is formed by combining three sections, namely a first cylindrical sleeve 10, a conical sleeve 11 and a second cylindrical cavity 12 from top to bottom in sequence, wherein the inner diameter of the first cylindrical sleeve is fixedly connected with the outer circumferential surface of the connecting piece through threads, the inner diameter of the second cylindrical cavity is smaller than that of the first cylindrical sleeve, and the conical sleeve is just connected with the first cylindrical sleeve and the second cylindrical cavity; the lower end surface of the connecting piece, the inner wall of the conical sleeve body and the inner wall of the second cylindrical cavity enclose to form a pre-combustion chamber;

the central line of the oil sprayer mounting hole is vertical to the upper end surface and the lower end surface of the connecting piece; the center line of the spark plug mounting hole and the center line of the second cylindrical cavity are intersected in the second cylindrical cavity, and a plane formed by the intersection of the center line of the spark plug mounting hole and the center line of the second cylindrical cavity is defined as an X plane;

the lower part of the second cylindrical cavity is provided with 6 uniformly distributed spray holes; all the spray holes are round straight holes, and the central lines of the spray holes are obliquely downward diffused outwards relative to the bottom surface of the second cylindrical cavity; 4 of the jet holes are inclined jet holes 8, and 2 of the jet holes are radial jet holes 9; the inclined spray holes are symmetrically distributed along the X plane, and 2 spray holes are respectively arranged at two sides of the inclined spray holes; the central lines of the radial spray holes are all positioned in an X plane; the included angles and the distances between the central lines of all the inclined jet holes and the central line of the second cylindrical cavity are equal; the included angles of the central lines of all the radial spray holes and the central line of the second cylindrical cavity are equal;

at least 1 of the jet holes is an inclined jet hole 8, and at least 1 of the jet holes is a radial jet hole 9; the central line of the inclined spray hole is not intersected, parallel and perpendicular to the central line of the second cylindrical cavity; the radial spray holes and the center line of the second cylindrical cavity are intersected in the precombustion chamber.

The 4 inclined jet holes are respectively distributed on two sides of the bottom surface of the precombustion chamber in a bilateral symmetry mode along a connecting line formed by the 2 radial jet holes.

As shown in fig. 2, the 2 radial nozzles are respectively positioned at the same direction with the air inlet side and the air outlet side of the engine, and the distribution can make the flame jet of the prechamber better cover the two sides; the circular arrows in the figure represent the tumble motion of the gases in the engine cylinder during the compression stroke, creating a more intense tumble motion inside the pre-combustion chamber.

The working process is as follows:

in the process of ascending of an engine piston 15 in a compression stroke, fresh charge in a main combustion chamber 13 of the engine enters a pre-combustion chamber 5 through inclined spray holes 8 and radial spray holes 9, then a pre-combustion chamber fuel injector 4 injects fuel to form combustible mixed gas mixed by gasoline and air in the pre-combustion chamber, and then a pre-combustion chamber spark plug 2 ignites to ignite the mixed gas in the pre-combustion chamber; the arrangement of 4 inclined jet holes in the precombustion chamber can utilize the tumble motion of gas in an engine cylinder in a compression stroke to form stronger tumble motion in the precombustion chamber; the airflow movement formed in the precombustion chamber can effectively help oil and gas mixing in the spraying stage in the precombustion chamber and can also help flame propagation and development in the ignition stage of a spark plug in the precombustion chamber, so that the jet speed of jet flame is improved;

the temperature and pressure in the precombustion chamber rise along with the combustion of the mixed gas, and when the pressure in the precombustion chamber is higher than that of the main combustion chamber 13 of the engine, the mixed gas in the precombustion chamber flows outwards through the inclined jet holes 8 and the radial jet holes 9 to form jet flow.