KR100202914B1 - Fuel injection valve for an internal combustion engine - Google Patents

Abstract

The present invention provides a fuel injection valve for an internal combustion engine.

The chamber 9 connected with the supply passage 5 is arrange | positioned at the distal end part of the combustion chamber side of the valve body 1, and the said chamber is a shaft from the end surface 7 of the combustion chamber side of the valve body 1 in radial direction. Outer rim range of the valve body 1 which divides the room 9 with respect to the combustion chamber of the internal combustion engine to which fuel is to be provided and which is divided by the pin 11 which holds the valve seat 15 which protruded in the direction A spring-loaded valve diaphragm 17 is securely fastened to the valve diaphragm. The valve seat 15 of the valve diaphragm 17 is provided with a valve sealing surface 19 for tight contact through a preload. The diaphragm 17 has an injection opening inlet 25, and the injection opening inlet 25 is disposed in the valve diaphragm 17 behind the valve sealing surface 19 as viewed in the injection flow direction of the surface material. A fuel injection valve for use in an engine is provided.

Description

Fuel injection valve for internal combustion engine

Techniques relating to fuel injection valves for internal combustion engines are known. In general, in the known fuel injection valve, the end face on the combustion chamber side of the valve body partitions the annular pressure chamber. The supply passage of the fuel injection pump is opened in the pressure chamber.

This pressure chamber is partitioned radially inward by a pin protruding axially from the end face of the valve body. The cross section of the fin is tapered in a conical shape at the distal end of the combustion chamber side to form a valve seat. In the pressure chamber, the distal end on the combustion chamber side is partitioned by a plate-shaped valve diaphragm. A sleeve is fitted in the outer rim of the valve diaphragm, and is fixed to the valve body by a tightening nut. In addition, an open inlet is provided at the center of the valve diaphragm, and the annular edge of the open inlet forms a sealed edge that works together with the valve seat. Since the sealing surface of the valve diaphragm has the fuel injection valve closed and closely contacts the valve seat via the preload, the pressure chamber is closed in the direction of the combustion chamber of the internal combustion engine to which fuel is to be supplied. In the case of injection, the pressure chamber is loaded with high fuel pressure through the supply passage. The high fuel pressure resists the preload force and lifts the sealing surface of the spring-elastic valve diaphragm from the valve seat. As a result, fuel injection is performed like a known compression pin nozzle through an annular gap provided in the pin, which is open controlled. The end of the injection process is controlled by terminating the high pressure supply to the pressure chamber. However, there is a drawback that the air fuel injection valve is not suitable for use in a direct injection internal combustion engine. The reason is that, using the above known fuel injection valve, only one injection jet directed in the axial direction with respect to the pin can be obtained.

In order to solve this problem, according to the present invention, the fuel injection valve for an internal combustion engine is provided with a valve body having a valve seat 15 for positioning and a movable valve member; The valve member has an elastically adjustable wall; An edge of the wall is fixed to the valve body; An adjustable wall of the valve member surrounds the room simultaneously with the distal end of the valve body; On the other side isolating the room in a combustion chamber adjacent to an adjustable wall of an internal combustion engine which has to be fueled; A supply passage for supplying the fuel high pressure by the fuel high pressure source is provided; The fuel supply passage is opened to the room; A valve sealing surface is provided on the movable valve member; It is possible for the valve sealing surface to be lifted from the valve seat of the position fixing under the action of the fuel high pressure generated and tightened upstream of the valve seat of the position fixing; At this time, at least one injection hole defined as the injection opening inlet is provided in such a way that the valve sealing surface is connected to the supply passage with one or more injection opening inlet located downstream of the valve sealing surface. ; It is comprised so that the said injection hole may be guided through the said valve member movable in the downstream of the said valve sealing surface. In the structure of this invention, it can also be used also for the fuel injection apparatus which uses a simple diaphragm type nozzle for a direct injection internal combustion engine. This is advantageous because it becomes possible by freely selecting the arrangement of the spray opening inlets located in the sealing sheet portion. In the above case, a plurality of spray opening inlets can be provided. Since the injection opening inlet is positioned so that the injection jet extends at a predetermined angle with respect to the axis of the shaft portion of the injection valve, proper fuel adjustment is possible even in the direct injection type internal combustion engine.

In addition to the arrangement of the pins protruding in the axial direction, it is also possible to install the valve seat in a spherical body fixed to the end face of the valve body. By this, the manufacturing time of the injection valve can be further shortened.

The injection opening inlet located on the lower side of the valve sealing surface may advantageously be directly formed into a spherical forming part provided in the valve valve diaphragm, or may be provided in a separate insert holding the valve sealing surface. . The insert is then inserted into the valve diaphragm. Forming the valve diaphragm into two parts as described above has the advantage of using a variety of materials. Therefore, a material having good spring elasticity characteristics can be used for the diaphragm, and a material having good strength characteristics and retention can be used for the diaphragm insert. It is also possible to enable the assembly unit system based on using a valve portion for receiving the valve sealing surface and the injection opening inlet. As a result, in the assembly unit system, the proper coupling to each internal combustion engine can be performed only by replacing the diaphragm insert using the universal valve body and the standardized valve diaphragm.

Alternatively, it is also possible to provide a complete seat portion and a spray hole in the valve diaphragm by a spherical insert (for example, a ball bearing spherical object) that can be manufactured by mass production. The spherical insert is in this case interlocked with a valve seat having an extremely simple structure, which is formed by the outflow opening inlet of the feed passage in both end faces of the valve body.

Another advantage is that the injection opening can be guided to the range of the center of the combustion chamber by injecting the pin and valve diaphragm into the combustion chamber.

The fixing of the valve diaphragm in the valve body is advantageous if it is performed by a tightening nut. For this purpose, a throttling plate or an adjusting ring is arranged between the valve diaphragm and the valve body for the purpose of regulating the opening inlet pressure of the injection valve. In this case it is particularly advantageous to carry out the adjustment, for example by means of a nut which is accessible from the outside. The reason for this is that the opening inlet pressure of the injection valve from the outside can be adjusted even after attaching in this manner.

Alternatively, it is possible to make unnecessary adjustments from the back which may be carried out in some cases and to weld the valve diaphragm to a ring coupled to the valve body.

In addition, by enclosing the end face on the combustion chamber side of the valve diaphragm with a cap-shaped fastening nut, it restricts the opening stroke of the valve diaphragm, thereby ensuring a fluid passage cross section defined between the valve seal names of the valve seat. It is advantageous because it becomes possible.

Another advantage of the present invention can be obtained by fixing the rotational position with respect to the pin of the movable valve member (valve diaphragm). Thereby, the stress which affects a sealing surface does not generate | occur | produce by the frictional connection which exists between the valve diaphragm of a tightening nut.

Therefore, by using the fuel injection valve according to the present invention, it is possible to simply combine the advantages of the bore-type nozzle with the advantages of the diaphragm nozzle, thereby ensuring a high level of functionality in the use of a few component parts. Will be.

1 is a longitudinal sectional view showing one embodiment of a fuel injection valve according to the present invention;

2 is an enlarged view of a valve seat formed of a valve diaphragm and pin.

* Symbol description for main parts of the drawing

1 valve body 3 connection

5: supply passage 7: end face

9: room 11: pin

13: sleeve 15: valve seat

17: valve diaphragm 19: valve sealing surface

21: molding 23: a room with a closed hole shape

25 injection opening inlet 27 tightening nut

29: Shades

The rotationally symmetrical valve body 1 shown in FIG. 1 has a connecting portion 3 for a supply line (not shown) of a fuel injection pump at one end thereof. From this connection part 3, the supply passage 5 which penetrates the valve body 1 in the longitudinal direction is derived. The supply passage 5 is open at the end face 7 in the valve body 1 and in contact with the combustion chamber of the internal combustion engine to which fuel is to be supplied. This end face 7 is adjacent to the room 9, which is the center projecting axially from the end face 7 radially inward in the first embodiment shown in FIG. It is partitioned by the pin 11, and is partitioned by the sleeve 13 in the radially outer side.

In this case, the conical trapezoidal fin 11 forms a valve seat 15 at a part of the conical surface. While the chamber 9 is partitioned on the combustion chamber side, the valve seat 15 is advantageously in contact with the valve diaphragm 17 formed of a spring elastically steel via a preload. The valve diaphragm 17 is bent in the direction of the chamber 9 and has a valve sealing surface 19. For this purpose, the plate-shaped valve diaphragm 17 which forms a movable valve member has a conical trapezoidal shaped part 21 (concave) which protruded in the direction of the combustion chamber at the height of the fin 11. The distal end portion of the combustion chamber side of the molding portion 21 is formed in a spherical shape, and in this case, the inner edge portion of the molding portion 21 forms a valve sealing surface 19 that works together with the valve seat 15. Doing. A blind-shaped chamber 19 is formed between the distal end of the combustion chamber side of the fin 11 and the bottom of the molding part 21.

This chamber 23 is located downstream in the spraying direction in a sealing cross section formed between the valve seat 15 and the valve sealing surface 19, and at least one, advantageously a plurality of injection opening inlets 25. ) Leads to the combustion chamber of the internal combustion engine.

The outer edge portion of the valve diaphragm 17 is tightly tightened tightly to the valve body 1 by the tightening nut 27 by fitting the sleeve 13. For this purpose, the tightening nut 27 has a shade 29 covering the outer edge of the valve diaphragm 17.

The outer diameter of the valve diaphragm 17 is made smaller than the inner diameter of the tightening nut 27 in order to ensure the function of fixing the position sufficient between the pin 11 and the valve diaphragm 17 to obtain the sealing property of the valve seat. In this way, the valve diaphragm 17 can be centered with respect to the pin 11 at the time of attachment.

The fuel injection in the fuel injection valve according to the present invention is performed by supplying fuel under high pressure to the room 9 by the injection pump through the supply passage 5. As a result of the pressure formation, the valve sealing surface 19 of the valve diaphragm 17 is lifted from the valve seat 15 in response to its preload force, so that the fuel has a hole shape clogged along the open sealing cross section. It flows into the room 23 and through the injection opening inlet 25 into the combustion chamber of the internal combustion engine to which fuel is to be supplied. The fuel injection is terminated by stopping the fuel high pressure supply to the chamber 9. As a result, since the pressure in the room 9 again falls below the preloading force of the valve diaphragm 17, the valve sealing surface 19 springs back to the valve seat 15 elastically.

Therefore, by using the fuel injection valve according to the present invention, it is possible to simply combine the advantages of the bore-type nozzle with the advantages of the diaphragm nozzle, thereby ensuring a high level of functionality in the use of a few component parts. Will be.

The present invention relates to a fuel injection valve, and more particularly to a fuel injection valve used in an internal combustion engine.

Claims (3)

A valve body 1 having a valve seat 15 for positioning and a movable valve member 17 are provided; The valve member 17 has an elastically adjustable wall; An edge of the wall is fixed to the valve body (1); An adjustable wall of the valve member (17) surrounds the room (9) simultaneously with the distal end (7) of the valve body (1); On the other side isolating the chamber 9 in a combustion chamber adjacent to an adjustable wall of an internal combustion engine which has to be fueled; A supply passage 5 for supplying the fuel high pressure by the fuel high pressure source is provided; The fuel supply passage (5) is opened into the chamber (9); A valve sealing surface 19 is provided on the movable valve member 17; It is possible for the valve sealing surface 19 to be lifted from the valve seat 15 in position fixing under the action of the fuel high pressure generated and tightened upstream of the valve seat 15 in position fixing; At this time, the injection opening inlet is formed such that the valve sealing surface 19 is connected to the supply passage 5 with one or more injection opening inlets 25 located downstream of the valve sealing surface 19. One or more injection holes defined as 25 are provided; A fuel injection valve of an internal combustion engine, characterized in that the injection hole is guided through the valve member (17) which is movable on the downstream side of the valve sealing surface (19). 2. The valve seat (15) according to claim 1, wherein the valve seat (15) is formed of a pin (11) protruding from the end face (7) on the combustion chamber side of the valve body (1) coaxially with respect to the axis of the valve body (1), The cross section of the pin 11 is decreasing in the direction of the movable valve member 17 formed by the valve diaphragm, and the movable valve member 17 is provided with a recess 21 continuously provided in the valve sealing surface 19. And an injection hole extends from the recess (21) as a starting point. The injection opening inlet 25 is advantageously arranged in a shaping portion 21 protruding in the direction of the combustion chamber from the end face of the movable valve member, which is advantageously formed as a valve valve diaphragm 17. A part of the wall facing the chamber 9 of the molding portion 21 forms a valve sealing surface 19, and has a hole shape clogged between the sealing surface 19 and the injection opening inlet 25. A fuel injection valve of an internal combustion engine, characterized by a room (23) remaining.