JP2022118756A - Direct injection engine high-pressure fuel delivery pipe assembly - Google Patents

Abstract

To reduce the stress of an adhesion portion between a main pipe and an injection valve socket without excessively spreading an adhesion area of the injection valve socket with respect to the main pipe.SOLUTION: A direct injection engine high-pressure fuel delivery pipe assembly 10 comprises a main pipe 11 in which a fuel passage 11a is formed, a plurality of injection valve sockets 21 into which fuel injection valves I are liquid-tightly inserted, and a plurality of attachment bosses 22 arranged in adjacent positions of the plurality of injection valve sockets 21. The injection valve sockets 21 are formed as socket units 20 integrally with the attachment bosses 22 which are arranged at the adjacent positions, and the socket units 20 comprise adhesion face parts 23 adhering to a peripheral face of the main pipe 11 in a position where the injection valve sockets 21 and the attachment bosses 22 are arranged, and protrusion plate parts 24 adhering to an external peripheral face of the main pipe 11 while protruding to the outside in a longitudinal direction of the main pipe 11 in plate shapes at least at one of end parts of the adhesion face parts 23 in the longitudinal direction of the main pipe 11.SELECTED DRAWING: Figure 1

Description

The present invention relates to a high-pressure fuel delivery pipe assembly for a direct-injection engine that is used to directly inject high-pressure fuel into the combustion chamber of a multi-cylinder engine.

Patent Literature 1 discloses an invention of a high-pressure fuel delivery pipe assembly for a direct-injection engine, which is used to directly inject high-pressure fuel into the combustion chamber of a multi-cylinder engine. The high-pressure fuel delivery pipe assembly for a direct injection engine disclosed in Patent Document 1 includes a main pipe in which a fuel passage to which pressurized fuel is supplied from a high-pressure fuel pump is formed, and a main pipe that is integrally fixed to the main pipe. 4 injection valve sockets with injection valve insertion holes into which the fuel injection valves are inserted in a liquid-tight manner, and 4 cylinders with bolt insertion holes that are integrally fixed to the main pipe and attach the main pipe to the engine. with mounting bosses.

JP 2010-007651 A

In this type of high-pressure fuel delivery pipe assembly for a direct injection engine, it is required to further increase the fuel injection pressure. When the fuel injection pressure is increased, it is necessary to further increase the strength of the fixing portion between the main pipe and the injection valve socket. For example, as shown in FIGS. The strength of the fixed portion between the main pipe 100 and the injection valve socket 101 can be further increased by increasing the fixing area of the injection valve socket 101 and increasing the wall thickness around the fixed portion of the injection valve socket 101 to the main pipe 100. can. However, if the fixing area of the injection valve socket 101 to the main pipe 100 is widened and the surrounding wall thickness is increased, the weight of the injection valve socket 101 may become too heavy. Further, even if the fixing area of the injection valve socket 101 to the main pipe 100 is increased, the strength of the fixing portion between the main pipe 100 and the injection valve socket 101 may not be increased sufficiently. SUMMARY OF THE INVENTION The present invention provides a high-pressure fuel delivery pipe assembly for a direct-injection engine that can reduce the stress at the fixed portion between the main pipe and the injection valve socket without excessively widening the fixing area of the injection valve socket to the main pipe. for the purpose.

In order to solve the above problems, the present invention provides a main pipe having a fuel passage through which pressurized fuel is supplied from a high-pressure fuel pump, and an injection valve insert into which a fuel injection valve is liquid-tightly inserted. a plurality of injection valve sockets having holes and arranged at positions along the longitudinal direction of the main pipe at predetermined intervals; and the plurality of injection valve sockets adjacent to each of the main pipes in the longitudinal direction. A high-pressure fuel delivery pipe assembly for a direct injection engine, comprising a plurality of mounting bosses provided at positions and having bolt insertion holes for inserting mounting bolts for mounting the main pipe to the engine, wherein the socket unit is a fixing surface fixed to the peripheral surface of the main pipe at a position where the injection valve socket and the mounting boss are arranged; A high-pressure fuel delivery pipe assembly for a direct-injection engine, characterized by comprising a projecting plate part projecting in a shape and fixed to the outer peripheral surface of the main pipe.

In this type of high pressure fuel delivery pipe assembly for a direct injection engine, an injection valve socket and a mounting boss are integrally formed as a socket unit, and a thick block shape is formed at the longitudinal end of the main pipe of the socket unit. When the socket unit is reinforced and fixed to the main pipe so as to extend in the longitudinal direction, the fixing strength of the socket unit to the main pipe can be increased. Since the block-shaped portion extending into the block shape is less likely to deform when the generated axial reaction force is applied, a large stress is generated in the portion of the main pipe to which the block-shaped portion is fixed. Become. In contrast, in the high-pressure fuel delivery pipe assembly for a direct injection engine of the present invention, the socket unit includes a fixing surface portion fixed to the peripheral surface of the main pipe at a position where the injection valve socket and the mounting boss are arranged; At least one of the ends of the main pipe in the longitudinal direction of the face portion is provided with a protruding plate portion that protrudes outward in the longitudinal direction in a plate shape and is fixed to the outer peripheral surface of the main pipe. The fixing strength can be increased, and even if an upward reaction force in the axial direction is applied to the injection valve socket when fuel is injected from the fuel injection valve, the projecting plate portion can receive deformation to some extent. A large stress is less likely to occur in the portion of the main pipe to which the projecting plate portion is fixed.

In the high-pressure fuel delivery pipe assembly for a direct-injection engine configured as described above, it is preferable that the protruding plate portion has a curved surface portion that rises gradually toward the fixing surface portion at the end portion between the fixing surface portion. When an axial reaction force is applied to the injection valve socket when fuel is injected from the fuel injection valve, a large stress is likely to occur between the fixing surface and the protruding plate, but the protruding plate is fixed. Since the curved surface portion that gradually rises as it approaches the fixing surface portion is formed at the end between the surface portions, the stress generated between the fixing surface portion and the protruding plate portion can be reduced.

In the high-pressure fuel delivery pipe assembly for a direct injection engine configured as described above,
It is preferable that the socket unit has a reinforcing plate in which the fixing surface portion and the protruding plate portion are integrally formed, and the injection valve socket and the mounting boss are fixed to the main pipe via the reinforcing plate. In this case, since the protruding plate portion is integrally formed as a reinforcing plate at the longitudinal end portion of the fixing surface portion, it is possible to reduce the labor required for processing the protruding plate portion to protrude from the socket unit. can.

1 is a perspective view of a high pressure fuel delivery pipe assembly for a direct injection engine of a first embodiment; FIG. FIG. 2 is a front view of FIG. 1; FIG. 3 is a cross-sectional view taken along line AA of FIG. 2; FIG. 3 is a cross-sectional view taken along line BB of FIG. 2; 3 is a cross-sectional view taken along line CC of FIG. 2; FIG. FIG. 4 is a perspective view of a high pressure fuel delivery pipe assembly for a direct injection engine of a second embodiment; FIG. 7 is a front view of FIG. 6; FIG. 8 is a cross-sectional view taken along line DD of FIG. 7; FIG. 8 is a cross-sectional view taken along line EE of FIG. 7; FIG. 8 is a cross-sectional view taken along line FF of FIG. 7; 1 is a front view of a conventional high pressure fuel delivery pipe assembly for a direct injection engine; FIG. FIG. 12 is a cross-sectional view taken along line GG of FIG. 11;

DETAILED DESCRIPTION OF THE INVENTION Embodiments of a high-pressure fuel delivery pipe assembly for a direct injection engine according to the present invention will be described below with reference to the accompanying drawings.
(First embodiment)
A high-pressure fuel delivery pipe assembly 10 for a direct-injection engine according to the first embodiment is used in an in-line four-cylinder direct-injection engine, and as shown in FIGS. One main pipe 11, four (plurality of) injection valve sockets 21 arranged in the main pipe 11 at predetermined intervals, and four sockets for attaching the main pipe 11 to the engine. It comprises (a plurality of) mounting bosses 22, joint members 13 fixed to the ends of the main pipe 11 in the longitudinal direction, and sensor mounting members 14 fixed to substantially the central portion of the main pipe 11 in the longitudinal direction. These members are fixed by brazing so as to be integrated as a whole, and after being fixed, they are subjected to surface treatment such as plating, if necessary.

The main pipe 11 is made of a metal material such as steel, and is obtained by cutting a straight tubular material extending linearly into a predetermined length. As shown in FIGS. A fuel passage 11a is formed extending to the As shown in FIGS. 3 and 4, on the peripheral surface of the main pipe 11, the same number of fuel injection valves I (in this embodiment, the fuel injection valves I are shown only in FIG. 2) are inserted into the engine and fixed. 4) communication holes 11b are formed, and these communication holes 11b have the same intervals as the intervals of the fuel injection valves I inserted into the engine in the longitudinal direction of the main pipe 11 and fixed. These communication holes 11b communicate the fuel passage 11a of the main pipe 11 with the internal space of the injection valve insertion hole 21a of the injection valve socket 21 together with a communication hole 21b formed in the injection valve socket 21, which will be described later. A fuel supply pipe (not shown) to which fuel pressurized from a high pressure fuel pump is supplied to the joint member 13 is fastened and fixed by a union nut (not shown). is supplied with pressurized fuel from A fuel pressure sensor (not shown) is attached to the sensor mounting member 14, and the fuel pressure in the fuel passage 11a is detected by the fuel pressure sensor.

As shown in FIGS. 1 and 2, four socket units 20 integrally formed with injection valve sockets 21 and mounting bosses 22 are fixed to the peripheral surface of the main pipe 11. The socket units 20 are A number corresponding to the number of fuel injection valves I are provided. The socket unit 20 is an iron forged product integrally provided with an injection valve socket 21 and a mounting boss 22, and is fixed to the peripheral surface of the main pipe 11 at a position where the injection valve socket 21 and the mounting boss 22 are arranged. The surface portion 23 and one or both (at least one) of the end portions of the main pipe 11 in the longitudinal direction of the fixing surface portion 23 protrude outward in the longitudinal direction of the main pipe 11 in a plate-like shape and are fixed to the outer peripheral surface of the main pipe 11 . and a protruding plate portion 24 integrally provided. The injection valve socket 21 of each socket unit 20 is arranged in a position where the communication hole 11b of the main pipe 11 is formed. It is stuck.

As shown in FIG. 3, the injection valve socket 21 is formed with an injection valve insertion hole 21a into which the fuel injection valve I is inserted in a liquid-tight manner. is inserted into A communication hole 21b extending toward the injection valve insertion hole 21a is formed in the fixing surface portion 23 and the injection valve socket 21. The communication hole 21b is connected to the fuel passage 11a of the main pipe 11 and the injection valve together with the communication hole 11b of the main pipe 11. It communicates with the injection valve insertion hole 21 a of the socket 21 .

As shown in FIGS. 1, 2 and 4, the mounting boss 22 is for mounting the main pipe 11 to the engine, and is integrally provided at the lower side of each injection valve socket 21. As shown in FIG. The mounting boss 22 is integrally provided on the side surface of the main pipe 11 in the longitudinal direction (axial direction) of the injection valve socket 21, and has a bolt insertion hole 22a for inserting a mounting bolt from above. It has a substantially cylindrical shape formed in the vertical direction. A diagonal member 22b is provided between the mounting boss 22 and the side surface of the injection valve socket 21, and the diagonal member 22b injects the fuel from the fuel injection valve I to the injection valve socket 21 in an axially upward direction. It has a function to prevent the injection valve socket 21 from tilting toward the mounting boss 22 when a force is applied.

As shown in FIGS. 1, 2 and 4, the fixing surface portion 23 is integrally formed at a position where the injection valve socket 21 and the mounting boss 22 are arranged in the longitudinal direction of the main pipe 11. 21 and the mounting boss 22 are fixed to the main pipe 11. As shown in FIG. The fixing surface portion 23 of this embodiment is fixed in close contact with the peripheral surface of the main pipe 11 within a range of approximately 150° in the circumferential direction. The fixing surface portion 23 is not limited to being fixed within the range of 150° in the circumferential direction of the peripheral surface of the main pipe 11, and may be fixed within the range of 120° to 180°.

As shown in FIGS. 1, 2 and 4, the protruding plate portion 24 protrudes outward in the longitudinal direction of the main pipe in a plate shape from the end of the fixing surface portion 23 in the longitudinal direction of the main pipe 11 so as to be attached to the main pipe. It adheres to the outer peripheral surface of 11. In this embodiment, the protruding plate portion 24 of the leftmost socket unit 20 protrudes rightward from the right end portion of the fixing surface portion 23 , and the protruding plate portion 24 of the rightmost socket unit 20 protrudes from the left end portion of the fixing surface portion 23 . The protruding plate portions 24 of the second and third socket units 20 from the left (third and second from the right) protrude outward from both left and right end portions of the fixing surface portion 23 .

The thickness (plate thickness) of the protruding plate portion 24 of this embodiment allows the socket unit 20 to be fixed to the main pipe 11 with high strength, while applying an axially upward reaction force to the injection valve socket 21. Although 1.5 mm is sometimes used as a thickness that can accommodate a moderate degree of deformation, it is not limited to this, and when the thickness (plate thickness) of the projecting plate portion 24 is in the range of 0.5 to 1.5 mm. Moreover, the stress in the fixed portion of the main pipe 11 can be reduced.

Further, the injection valve sockets 21 of the socket units 20 excluding the left end and the right end have a greater reaction force directed upward in the axial direction than the injection valve sockets 21 of the socket units 20 at the left end and the right end when the fuel is injected from the fuel injection valve I. will be added. For this reason, in this embodiment, the protruding plate portion 24 of the socket unit 20 excluding the left end and the right end is arranged axially toward the injection valve socket 21 while increasing the fixing strength of the socket unit 20 to the main pipe 11 . The main pipe 11 is projected with a length of 6 mm to the outside in the longitudinal direction of the main pipe 11 as a length that can accommodate a moderate degree of deformation when an upward reaction force is applied. The projection is not limited to a length, and may be a projection of 6 mm or more to the outside in the longitudinal direction of the main pipe 11 . In this embodiment, the protruding plate portions 24 of the left end and right end socket units 20 protrude in the longitudinal direction of the main pipe 11 with a length of 3 mm. It may protrude outward in the longitudinal direction with a length of 3 mm or more.

As shown in FIG. 5, the protruding plate portion 24 is fixed in close contact with the peripheral surface of the main pipe 11 within a range of approximately 150° in the circumferential direction, similar to the fixing surface portion 23 . It should be noted that the protruding plate portion 24 is not limited to being fixed in the range of 150° in the circumferential direction of the peripheral surface of the main pipe 11, similarly to the fixing surface portion 23, and is fixed in the range of 120° to 180°. It may be

As shown in FIG. 4, the protruding plate portion 24 has a curved surface portion 24a formed of an R surface that rises gradually toward the fixing surface portion 23 at the end portion between the fixing surface portion 23 and the fixing surface portion 23. As shown in FIG. The curved surface portion 24a has a function of reducing the stress generated between the projecting plate portion 24 and the fixing surface portion 23. As shown in FIG. The radius of curvature of the curved surface portion 24a in this embodiment is set to R1 (1 mm). .

When manufacturing the high-pressure fuel delivery pipe assembly 10 for a direct injection engine, sealing plugs 12 are provided at both ends of the main pipe 11, joint members 13 are provided at the ends of the main pipe 11 in the longitudinal direction, and the center of the main pipe 11 in the longitudinal direction is provided. A fixing surface portion of a socket unit 20 in which an injection valve socket 21 and a mounting boss 22 are integrally formed so that the sensor mounting member 14 and the communication hole 11b of the main pipe 11 are formed at the position where the communication hole 21b communicates with the communication hole 21b. 23 and the projecting plate portion 24 are temporarily fixed by welding or the like so as to be in close contact with the main pipe 11, and each component is liquid-tightly fixed to the main pipe 11 by brazing.

In the high-pressure fuel delivery pipe assembly 10 for a direct-injection engine configured as described above, when high-pressure fuel is injected from the fuel injection valve I into each cylinder of the engine, the fuel from the fuel injection valve I enters the injection valve socket 21. A reaction force generated when fuel is injected is applied axially upward to the injection valve socket 21 , and stress is generated between the main pipe 11 and the fixing surface portion 23 for fixing the socket unit 20 .

In the high-pressure fuel delivery pipe assembly 10 for a direct injection engine of this embodiment, the injection valve socket 21 is integrally formed with a mounting boss 22 arranged at an adjacent position as a socket unit 20, and the socket unit 20 is the injection valve. a fixing surface portion 23 fixed to the peripheral surface of the main pipe 11 at a position where the socket 21 and the mounting boss 22 are arranged; A protruding plate portion 24 that protrudes outward in a plate shape and is fixed to the outer peripheral surface of the main pipe 11 is provided.

In this type of high-pressure fuel delivery pipe assembly for a direct injection engine, the injection valve socket and the mounting boss are integrally formed as a socket unit, and the lengthwise end of the main pipe of the socket unit has a thickness (for example, 3 mm to 5 mm). ) is reinforced so as to extend in the longitudinal direction and fixed to the main pipe, the fixing strength of the socket unit to the main pipe can be increased. When the axial reaction force generated when spraying is applied, the block-shaped portion extending into the block shape is difficult to deform. stress will occur.

In contrast, in the high-pressure fuel delivery pipe assembly 10 for a direct injection engine of this embodiment, the socket unit 20 is fixed to the peripheral surface of the main pipe 11 at the position where the injection valve socket 21 and the mounting boss 22 are arranged. and a protruding plate portion 24 that protrudes outward in the longitudinal direction of the main pipe 11 from the end portion of the fixing surface portion 23 in the longitudinal direction of the main pipe 11 and is fixed to the outer peripheral surface of the main pipe. In addition, the projecting plate portion 24 of this embodiment has a thickness of 1.5 mm. As a result, the fixing strength of the socket unit 20 to the main pipe 11 can be increased, and even if an axial reaction force generated when fuel is injected from the fuel injection valve I is applied to the injection valve socket 21, the socket unit 20 protrudes. Since the plate portion 24 can receive deformation to some extent, a large stress is less likely to occur in the portion of the main pipe 11 to which the projecting plate portion 24 is fixed.

In the high-pressure fuel delivery pipe assembly 10 for a direct injection engine, the protruding plate portion 24 is formed with a curved surface portion 24a that rises gradually toward the fixing surface portion 23 at the end portion between the fixing surface portion 23 and the fixing surface portion 23 . When an axial reaction force is applied to the injection valve socket 21 when fuel is injected from the fuel injection valve I, a large stress is likely to occur between the fixing surface portion 23 and the projecting plate portion 24. Since the portion 24 has a curved surface portion 24a which rises gradually as it approaches the fixing surface portion 23 at the end portion between the fixing surface portion 23, the stress generated between the fixing surface portion 23 and the projecting plate portion 24 is reduced. be able to.

(Second embodiment)
In the high-pressure fuel delivery pipe assembly 10 for the direct injection engine of the first embodiment, the fixing surface portion 23 for fixing the socket unit 20 to the peripheral surface of the main pipe 11 is integrated with the injection valve socket 21 and the mounting boss 22. formed. On the other hand, as shown in FIGS. 6 to 10, in the high-pressure fuel delivery pipe assembly 10 for a direct injection engine of the second embodiment, a fixing surface portion for fixing the socket unit 20 to the peripheral surface of the main pipe 11 is provided. Reference numeral 23 designates the injection valve socket 21 and the mounting boss 22 as separate bodies, and includes a reinforcing plate 25 integrally forming the fixing surface portion 23 and the projecting plate portion 24. The injection valve socket 21 and the mounting boss 22 are reinforced. It is fixed to the peripheral surface of the main pipe 11 via the plate 25 . The protruding plate portion 24 is formed by press working to be thinner than the fixing surface portion 23 to which the injection valve socket 21 and the mounting boss 22 are fixed. A curved surface portion 24a that gradually rises as it approaches the fixing surface portion 23 is formed.

In the high-pressure fuel delivery pipe assembly 10 for a direct injection engine of the second embodiment as well, the same effects as those of the first embodiment can be obtained, and the projecting plate portion 24 serves as a reinforcing plate 25 and extends in the longitudinal direction of the fixing surface portion 23 . is formed integrally with the end of the socket unit 20, it is possible to reduce the time and effort of the processing work for protruding and providing the protruding plate portion 24 on the socket unit 20. As shown in FIG.

In the left end and right end socket units 20 of the high-pressure fuel delivery pipe assembly 10 for a direct injection engine of the first and second embodiments, the protruding plate portion 24 is attached to one end portion of the main pipe 11 of the fixing surface portion 23 in the longitudinal direction. However, it is not limited to this, and the projecting plate portions 24 may be provided at both ends of the fixing surface portion 23 of the main pipe 11 in the longitudinal direction. Similarly, in the socket units 20 other than the left end and the right end, the projecting plate portions 24 are provided at both ends of the fixing surface portion 23 in the longitudinal direction of the main pipe 11. Although reduced, the protruding plate portion 24 may be provided only at one end portion of the fixing surface portion 23 of the main pipe 11 in the longitudinal direction.

The high-pressure fuel delivery pipe assembly 10 for a direct injection engine of the first and second embodiments has four injection valve sockets 21 and four mounting bosses 22 corresponding to an in-line four-cylinder direct injection engine. However, it is not limited to this, and two high-pressure fuel delivery pipe assemblies 10 for a direct injection engine of each embodiment may be used for a V-type 8-cylinder direct injection engine. . The high-pressure fuel delivery pipe assembly 10 for a direct injection engine of the first and second embodiments is provided with three or more injection valve sockets 21 and three or more mounting bosses 22, and has three or more cylinders in-line or It may be used for a V-type direct injection engine.

DESCRIPTION OF SYMBOLS 10... High pressure fuel delivery pipe assembly for direct injection engines 11... Main pipe 11a... Fuel passage 20... Socket unit 21... Injection valve socket 21a... Injection valve insertion hole 22... Mounting boss 23... Fixing surface part 24... projecting plate portion, 24a... curved surface portion, 25... reinforcing plate, I... fuel injection valve.

Claims (3)

a main pipe formed therein with a fuel passage to which fuel pressurized from a high-pressure fuel pump is supplied;
a plurality of injection valve sockets having injection valve insertion holes into which fuel injection valves are liquid-tightly inserted, and arranged at positions spaced apart by a predetermined interval along the longitudinal direction of the main pipe;
A plurality of mounting bosses provided at positions adjacent to the main pipes of the plurality of injection valve sockets in the longitudinal direction and having bolt insertion holes for inserting mounting bolts for mounting the main pipes to the engine. A high pressure fuel delivery pipe assembly for a direct injection engine comprising:
the injection valve socket is formed integrally with the adjacent mounting boss as a socket unit;
The socket unit has at least one of a fixing surface portion fixed to the peripheral surface of the main pipe at a position where the injection valve socket and the mounting boss are arranged, and an end portion of the fixing surface portion in the longitudinal direction of the main pipe. A high-pressure fuel delivery pipe assembly for a direct-injection engine, comprising: a protruding plate portion that protrudes outward in the longitudinal direction in a plate shape and is fixed to the outer peripheral surface of the main pipe. A high pressure fuel delivery pipe assembly for a direct injection engine according to claim 1,
A high-pressure fuel delivery pipe assembly for a direct-injection engine, wherein the protruding plate portion has a curved surface portion that rises gradually as it approaches the fixing surface portion at an end portion between the fixing surface portion and the fixing surface portion. The high-pressure fuel delivery pipe assembly for a direct injection engine according to claim 1 or 2,
The socket unit has a reinforcing plate integrally formed with the fixing surface portion and the projecting plate portion, and the injection valve socket and the mounting boss are fixed to the main pipe via the reinforcing plate. High pressure fuel delivery pipe assembly for direct injection engines.

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