Fuel delivery structure for cylinder injection engine

Abstract

To approximately suppress occurrence of abnormal sound and noise resulting from fuel pressure pulsation in a fuel delivery pipe without causing cost increase.SOLUTION: A fuel delivery structure for a cylinder injection engine 1 includes a cylinder head 2, a cylinder head cover 3, an injector 4 for injecting fuel into a combustion chamber of the cylinder head 2, and a fuel delivery pipe 5 for forcibly feeding and supplying the fuel to the injector 4, where the fuel is injected directly into the combustion chamber to cause combustion with spark ignition. On a wave belly part AN of the fuel delivery pipe 5, whose amplitude or displacement is relatively greater or maximum when the fuel delivery pipe 5 is vibrated with the injection of fuel by the injector 4, an accessory part AP of the cylinder injection engine 1 such as a pressure sensor 6 or a union bolt 9 is mounted.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a spark ignition engine mounted on a vehicle, and more particularly to a fuel delivery structure for a direct injection engine that injects fuel directly into a combustion chamber. [Background technology]

[0002] Patent Document 1 describes an invention related to a fuel delivery structure (fuel delivery pipe) for an engine. The fuel delivery pipe described in Patent Document 1 includes a fuel delivery pipe main body to which multiple injectors are attached, and a hollow damper member having a sealed space that is provided inside the fuel delivery pipe main body. The fuel delivery pipe is configured such that the damper member deforms to absorb fuel pressure pulsation when fuel supplied into the fuel delivery pipe main body is distributed and supplied to each injector. Furthermore, the fuel delivery pipe described in Patent Document 1 has a mass body (damper mass) attached to the wall of the damper member, which is the part that absorbs fuel pressure pulsation. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2010-180727 A Summary of the Invention [Problem to be solved by the invention]

[0004] The fuel delivery structure described in the above Patent Document 1 is used in a cylinder injection engine (so-called direct injection engine) that directly injects fuel from an injector into a combustion chamber. The fuel delivery pipe of the fuel delivery structure distributes and supplies high-pressure fuel pumped from a fuel pump to a plurality of injectors. The fuel delivery pipe is attached and fixed to a cylinder head cover of the direct injection engine. In a direct injection engine, fuel injection by the injector is performed intermittently, and pulsation (fuel pressure pulsation) may occur in the pressure of the fuel flowing in the fuel delivery pipe. When such fuel pressure pulsation occurs, there is a concern that vibration caused by it is transmitted to the cylinder head cover, causing resonance or resonation in the cylinder head cover, or that abnormal sounds or noises are emitted from the cylinder head cover. Therefore, in the fuel delivery pipe described in Patent Document 1, a mass body that functions as a damper mass is added to the hollow damper member as described above. Therefore, according to the engine fuel delivery structure described in Patent Document 1, the damper member to which a mass has been added can function as a mass damper, effectively absorbing or damping the fuel pressure pulsation in the fuel delivery pipe.

[0005] However, in the fuel delivery pipe described in the above Patent Document 1, the mass body is added to the damper member, which increases the number of processing steps and the material cost, and this causes an increase in the cost of the direct injection engine. The above-mentioned problem of abnormal sounds and noise emission from the cylinder head cover can be addressed by, for example, adding reinforcing ribs to the cylinder head cover or increasing the plate thickness of the cylinder head cover to increase the strength and rigidity of the cylinder head cover. Alternatively, it is also possible to provide a cover or soundproofing material to block the emission of noise and vibration. However, adding ribs or increasing the plate thickness goes against the demand for weight reduction. In either case, this ultimately causes an increase in the cost of the direct injection engine.

[0006] This invention was devised with an eye toward the technical challenges described above, and aims to provide a fuel delivery structure for a direct injection engine that can appropriately suppress the generation of abnormal sounds and noise caused by fuel pressure pulsation in the fuel delivery pipe without incurring increased costs. [Means for solving the problem]

[0007] In order to achieve the above-mentioned object, the present invention provides a fuel delivery structure for a direct injection engine comprising a cylinder head, a cylinder head cover attached to the cylinder head and covering an upper surface of the cylinder head, an injector that injects fuel into a combustion chamber of the cylinder head, and a fuel delivery pipe that pressure-feeds and supplies the fuel to the injector, the fuel being directly injected into the combustion chamber and burned by spark ignition, the fuel delivery structure comprising an accessory part that is involved in the structure or operation of the direct injection engine, the fuel delivery pipe having a wave midpoint where the amplitude or displacement when vibrating in conjunction with the injection of the fuel by the injector is maximized or where the amplitude or displacement is relatively large, and the accessory part is attached to the wave midpoint.

[0008] The fuel delivery pipe in the present invention may be arranged so as to be connected to the injector directly above the injector (substantially directly above in the vertical direction) and may be fixed to the cylinder head cover.

[0009] The injector in the present invention may be arranged directly above the cylinder head cover and the combustion chamber (substantially directly above in the vertical direction).

[0010] The accessory in the present invention may be a pressure sensor that detects the pressure of the fuel in the fuel delivery pipe.

[0011] The accessory in the present invention may be a joint member that connects the fuel delivery pipe and a fuel hose that supplies the fuel to the fuel delivery pipe.

[0012] The accessory in the present invention may be an electric wire connected to an electrical component of the direct injection engine. Effect of the Invention

[0013] The engine targeted by this invention is, for example, a spark ignition engine such as a gasoline engine, and is also a direct injection engine (so-called direct injection engine) that directly injects fuel into a combustion chamber using an injector. A fuel delivery structure for supplying high-pressure fuel to the injector includes a fuel delivery pipe that pressure-transmits fuel between a fuel pump and the injector. When the injector intermittently injects fuel, the fuel delivery pipe vibrates due to pulsation of fuel pressure (fuel pressure pulsation) in the fuel delivery pipe. When the fuel delivery pipe vibrates, the vibration is transmitted to the cylinder head cover, which may cause resonance or vibration in the cylinder head cover, or may cause abnormal noise or noise to be emitted from the cylinder head cover. Therefore, in the fuel delivery structure for a direct injection engine of this invention, a predetermined accessory of the direct injection engine is attached to the midpoint of the fuel delivery pipe. The wave bottom of the fuel delivery pipe is a portion that becomes an antinode of the vibration mode when the fuel delivery pipe vibrates as described above, that is, a portion where the amplitude or displacement of the vibration becomes relatively large or is maximum. The accessories of the direct injection engine are existing parts or members that are necessary for constituting the direct injection engine, and necessarily have a predetermined mass. Therefore, in the fuel delivery structure of the direct injection engine of the present invention, the accessories attached to the wave bottom as described above can be made to function as a damper mass. In other words, the fuel delivery pipe with the mass of the accessories added to the wave bottom can be made to function as a mass damper. Therefore, the vibration of the fuel delivery pipe can be easily and effectively absorbed or damped by using existing accessories without using special parts or members, vibration damping mechanisms, etc.

[0014] The fuel delivery structure of the direct injection engine of the present invention is applied to a direct injection engine in which the fuel delivery pipe is disposed directly above the injector, i.e., almost directly above the injector in the vertical direction. Alternatively, the fuel delivery structure of the direct injection engine of the present invention is applied to a direct injection engine in which the fuel delivery pipe is disposed directly above the cylinder head cover and the combustion chamber of the cylinder head, i.e., a so-called center injection type direct injection engine. In a direct injection engine of such a configuration, the fuel delivery pipe is connected to the injector in the space between the fuel delivery pipe and the injector, and the diameter of the fuel delivery pipe is large to pump high-pressure fuel, so the distance between the fuel delivery pipe and the cylinder head cover is long. In other words, the height of the boss member at the portion where the fuel delivery pipe is fixed to the cylinder head cover is large. Therefore, the fuel delivery pipe is more likely to vibrate. In contrast to a direct injection engine of such a configuration, in the fuel delivery structure of the direct injection engine of the present invention, as described above, existing accessories can be attached to the wave midpoint of the fuel delivery pipe, thereby easily and effectively absorbing or damping vibrations of the fuel delivery pipe.

[0015] In the fuel delivery structure for a direct injection engine of the present invention, for example, a pressure sensor (fuel pressure sensor) that detects the pressure of the fuel, or a joint member (union bolt, etc.) that connects the fuel delivery pipe and the fuel hose, or an electric wire (wire harness, etc.) that connects to electrical components are used as accessories for the direct injection engine as described above. Therefore, by utilizing these existing parts and members, it is possible to easily absorb or dampen the vibration of the fuel delivery pipe without increasing costs.

[0016] Therefore, according to the fuel delivery structure for a direct injection engine of the present invention, it is possible to appropriately suppress the generation of abnormal sounds and noises caused by fuel pressure pulsation in the fuel delivery pipe without incurring an increase in costs. [Brief description of the drawings]

[0017] [Figure 1] FIG. 1 is a diagram for explaining a fuel delivery structure of a direct injection engine of the present invention, and is a perspective view showing a cylinder head and a cylinder head cover of the direct injection engine to which the fuel delivery structure of the present invention is applied. [Diagram 2] FIG. 2 is a diagram for explaining the fuel delivery structure of the direct injection engine of the present invention, and is a perspective view showing the basic structure of an injector. [Diagram 3] FIG. 3 is a diagram for explaining the fuel delivery structure of the direct injection engine of the present invention, and is a perspective view showing the basic structure of a fuel delivery pipe. [Figure 4] FIG. 4 is a diagram for explaining the fuel delivery structure of the direct injection engine of the present invention, and is a perspective view showing the state in which the fuel delivery pipe is arranged in the cylinder head cover and a wire harness (accessory part) used in the direct injection engine. [Diagram 5] FIG. 5 is a diagram for explaining the fuel delivery structure of the direct injection engine of the present invention, and is a top view showing a state in which a fuel pressure sensor (accessory part) is attached to the rear end (wave bottom portion) of the fuel delivery pipe. [Figure 6] FIG. 6 is a diagram showing an example of an accessory of a cylinder injection engine to be attached to a bottom portion of a fuel delivery pipe, and is a perspective view showing the shape of a union bolt (accessory) that connects the fuel delivery pipe and the fuel hose. [Figure 7] FIG. 7 is a diagram showing an example of an accessory of a cylinder injection engine that is attached to the bottom of a fuel delivery pipe, and is a schematic diagram showing an image of the fuel delivery pipe and the fuel hose being connected with a union bolt (accessory). [Figure 8] FIG. 8 is a diagram for explaining the action and effect of the fuel delivery structure of the cylinder injection engine of the present invention, and is a diagram showing the result of frequency analysis of a state in which a union bolt (accessory part) is attached to the wave bottom of the fuel delivery pipe. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described with reference to the accompanying drawings. Note that the following embodiment is merely an example of a specific embodiment of the present invention, and is not intended to limit the present invention.

[0019] The direct injection engine in the embodiment of the present invention is typically a spark ignition engine using gasoline or other fuel such as LP gas, alcohol, or hydrogen, and in particular is a direct injection (direct injection) engine that directly injects fuel into the combustion chamber. Furthermore, the direct injection engine targeted in the embodiment of the present invention is a so-called center injection direct injection engine in which an injector that injects fuel is disposed almost directly above the combustion chamber, as will be described later. And, as shown in FIG. 1, the direct injection engine (hereinafter, engine) 1 in the embodiment of the present invention is provided with a cylinder head cover 3 that covers the upper surface of a cylinder head 2.

[0020] The cylinder head cover 3 is made of metal, such as an aluminum alloy or a magnesium alloy, and has higher strength and rigidity than existing "resin cylinder head covers." For example, in the example shown in Fig. 1, an aluminum alloy cylinder head cover 3 produced by aluminum die casting is used. As shown in Fig. 1, the cylinder head cover 3 is formed with an injector mounting hole 3a for mounting an injector 4, which will be described later, and a boss 3b for a fastening bolt for fixing a fuel delivery pipe 5, which will be described later.

[0021] The injector mounting holes 3a are through-holes formed at predetermined positions on the cylinder head cover 3 corresponding to the positions of the injectors 4 installed directly above the combustion chambers (not shown) formed in the cylinder head 2. In the example shown in Fig. 1, the cylinder head cover 3 is provided with the injector mounting holes 3a at four positions corresponding to the four injectors 4, respectively.

[0022] The fastening bolt boss 3b is a boss-shaped portion for attaching the fuel delivery pipe 5 to the cylinder head cover 3 by fastening a bolt. A screw hole (not shown) for screwing in a fastening bolt (not shown) is formed in the fastening bolt boss 3b.

[0023] In addition, the cylinder head cover 3 is formed with an ignition plug arrangement hole 3c for fixing an ignition plug (not shown), and bolt holes 3d for attaching the cylinder head cover 3 to the cylinder head 2 by bolting.

[0024] In a direct injection engine such as the engine 1 according to the embodiment of the present invention, the cylinder head cover 3 is required to have higher strength and rigidity than a conventional port injection engine in order to cope with, for example, the increased fuel injection pressure. In addition, by adopting the above-mentioned center injection system, the space available for arranging the injector 4 on the cylinder head cover 3 is reduced, which results in a reduced strength margin for the cylinder head cover 3. For this reason, the engine 1 according to the embodiment of the present invention adopts a metal cylinder head cover 3 with high strength and rigidity. This makes it possible to appropriately ensure the strength and rigidity of the cylinder head cover 3 in order to cope with the increased fuel injection pressure and the special structure of the center injection system.

[0025] The fuel delivery structure of the direct injection engine in the embodiment of the present invention includes an injector 4 and a fuel delivery pipe 5, as shown in FIGS.

[0026] The injector 4 is a component that injects fuel into the combustion chamber of the cylinder head 2. As described above, the engine 1 in the embodiment of the present invention is a direct injection engine of the center injection type. Therefore, the injector 4 is disposed directly above the cylinder head cover 3 and the combustion chamber in the cylinder head 2 (almost directly above in the vertical direction).

[0027] As shown in Fig. 2, the injector 4 basically has the same configuration as a conventional "center injection type injector." That is, the injector 4 has a body portion (nozzle holder) 4a that is substantially straight, and an injector mounting portion 5b of a fuel delivery pipe 5 (described later) is connected to an upper end portion 4b of the body portion 4a, through which high-pressure fuel is supplied from the fuel delivery pipe 5. The injector 4 has a valve mechanism (not shown) formed inside the body portion 4a, including a solenoid (not shown) and a plunger (not shown). An injection nozzle portion 4c that injects fuel directly into the combustion chamber of the cylinder head 2 is formed at the tip (lower end) of the body portion 4a.

[0028] In the example shown in Fig. 2, the injector 4 includes a nozzle holder clamp 4d. The nozzle holder clamp 4d clamps and connects the upper end 4b of the injector 4 to the injector mounting portion 5b of the fuel delivery pipe 5. The nozzle holder clamp 4d is configured to press the injector 4 toward the cylinder head 2 by the elastic force of a spring (not shown). For this reason, for example, when the engine 1 is started, when the fuel injection pressure is relatively low, the movement of the injector 4 due to the combustion pressure can be suppressed, and the airtightness between the injector 4 and the cylinder head 2 can be improved. In addition, the vibration and noise caused by the movement of the injector 4 can be reduced.

[0029] The fuel delivery pipe 5 pressure-feeds high-pressure fuel discharged from a fuel pump (not shown) to the injectors 4. In the example shown in Fig. 3, an injector 4 is installed in each of four injector mounting holes 3a formed in the cylinder head cover 3, and the fuel delivery pipe 5 distributes and supplies fuel to the four injectors 4.

[0030] 3, the fuel delivery pipe 5 basically has the same structure as a conventional "fuel delivery pipe for a direct injection engine." That is, it has a main pipe section 5a having a straight pipe shape with a predetermined length according to the number of injectors 4 that supply fuel, and an injector attachment section 5b.

[0031] The main pipe section 5a is a tubular member that is connected to the fuel pump and extends in the direction of the main flow of the fuel discharged from the fuel pump. Therefore, the length direction of the main pipe section 5a corresponds to the flow direction or supply direction of the main flow of the fuel in the fuel delivery pipe 5.

[0032] The injector attachment portion 5b is a boss-shaped portion branched off from the main pipe portion 5a, and is used to connect and attach the injector 4. As described above, the upper end portion 4b of the injector 4 is attached to the injector attachment portion 5b using the nozzle holder clamp 4d.

[0033] In the example shown in FIG. 3, the fuel pressure sensor 6 is attached to a portion AN1 near the center in the longitudinal direction of the main pipe portion 5a of the fuel delivery pipe 5. In the example shown in FIG. 5, which will be described later, the fuel pressure sensor 6 is attached to a portion AN2 near the end (the right end in FIG. 5) in the longitudinal direction of the main pipe portion 5a of the fuel delivery pipe 5. The fuel pressure sensor 6 is a pressure sensor that detects the pressure of the high-pressure fuel injected from the injector 4, and is an accessory AP of the entire engine 1 including the fuel delivery structure. The accessory AP is an existing part or member that is necessary to configure the engine 1. As will be described later, in the fuel delivery structure of the direct injection engine in the embodiment of the present invention, the accessory AP such as the fuel pressure sensor 6 is attached to the above-mentioned portions AN1 and AN2, i.e., the wave midpoints AN1 and AN2 of the fuel delivery pipe 5, and functions as a "damper mass."

[0034] Furthermore, in this embodiment of the present invention, the fuel delivery pipe 5 is disposed so as to be connected to the upper end 4b of the injector 4 directly above (directly above in the vertical direction) the injector 4. In this state, the fuel delivery pipe 5 is fixed to the metallic cylinder head cover 3.

[0035] In order to fix the fuel delivery pipe 5 to the cylinder head cover 3 as described above, a fastening bolt boss 5c is formed in the fuel delivery pipe 5. The fastening bolt boss 5c is a boss-shaped portion for attaching the fuel delivery pipe 5 to the cylinder head cover 3 by fastening with a bolt. As shown in Figures 3 and 4, the fastening bolt boss 5c is formed with a bolt hole (through hole) 5d for inserting the fastening bolt 7.

[0036] Furthermore, in the fuel delivery structure for a direct injection engine in the embodiment of the present invention, a predetermined accessory part AP of the engine 1 is attached to the wave bottom portion AN of the fuel delivery pipe 5.

[0037] The wave midpoint AN is a portion that becomes an antinode of the vibration mode when the fuel delivery pipe 5 vibrates due to the fuel pressure pulsation as described above, that is, a portion where the amplitude or displacement of the vibration becomes relatively large, or a portion where the amplitude or displacement of the vibration becomes maximum. In the example shown in FIG. 3 described above, the fuel pressure sensor 6 is attached as the accessory AP to a portion AN1 near the center in the longitudinal direction of the main pipe portion 5a of the fuel delivery pipe 5. That is, in the example shown in FIG. 3, the portion AN1 is the wave midpoint AN1 of the fuel delivery pipe 5. Also, in the example shown in FIG. 5, the fuel pressure sensor 6 is attached as the accessory AP to a portion AN2 near the tip (the end portion on the right side in FIG. 5) in the longitudinal direction of the main pipe portion 5a of the fuel delivery pipe 5. That is, in the example shown in FIG. 5, the portion AN2 is the wave midpoint AN2 of the fuel delivery pipe 5.

[0038] An accessory AP of the engine 1 is something that is involved in the structure or operation of the engine 1, or something that constitutes the engine 1, and is an essential part or member for constituting the engine 1. In the example shown in Figs. 3 and 5, a fuel pressure sensor (pressure sensor) 6 is attached to the fuel delivery pipe 5 as the accessory AP. The fuel pressure sensor 6 necessarily has a certain mass. Therefore, by attaching the fuel pressure sensor 6 to the wave bottom portion AN of the fuel delivery pipe 5, when the fuel delivery pipe 5 vibrates, the fuel pressure sensor 6 functions as a damper mass in the vibration system.

[0039] That is, in the fuel delivery structure for a direct injection engine according to the embodiment of the present invention, the fuel delivery pipe 5 in which the mass of the fuel pressure sensor 6 is added to the wave bottom portion AN as described above can function as a mass damper. Therefore, by utilizing an existing accessory AP such as the fuel pressure sensor 6, the vibration of the fuel delivery pipe 5 can be easily and effectively absorbed or damped.

[0040] In the fuel delivery structure for a direct injection engine according to the embodiment of the present invention, in addition to the fuel pressure sensor 6 as described above, a predetermined accessory AP may be attached to the midpoint AN of the fuel delivery pipe 5. For example, a wire harness 8 as shown in FIG. 4 may be attached to the midpoint AN of the fuel delivery pipe 5 to function as a damper mass. The wire harness 8 is an electric wire or a bundle of electric wires that connects to electrical components (not shown) of the engine 1, and is an accessory AP that is necessary for operating the engine 1. Although not shown in FIG. 4, a predetermined bundling portion (not shown) of such a wire harness 8 is attached and fixed to the midpoint AN of the fuel delivery pipe 5 to function as a damper mass in the vibration system of the fuel delivery pipe 5, similar to the case of the fuel pressure sensor 6 described above.

[0041] Also, a union bolt 9 as shown in Fig. 6 may be attached to the midpoint AN of the fuel delivery pipe 5. As shown in the image of Fig. 7, the union bolt 9 is a joint member that connects the fuel delivery pipe 5 to a fuel hose 10 that supplies high-pressure fuel to the fuel delivery pipe 5, and is an accessory AP that is necessary for configuring the engine 1 (particularly, the fuel delivery structure of the engine 1). For example, by attaching and fixing the union bolt 9 adjusted to a required weight to the midpoint AN of the fuel delivery pipe 5, it can function as a damper mass in the vibration system of the fuel delivery pipe 5, similar to the case of the fuel pressure sensor 6 described above.

[0042] Fig. 8 shows the analysis results for explaining the action and effect of the fuel delivery structure of the direct injection engine in the embodiment of the present invention. The example shown in Fig. 8 shows the analysis results of the vibration mode in the direction perpendicular to the surface of the cylinder head cover 3 when the above-mentioned union bolt 9 (i.e., accessory part AP) is attached as a damper mass to the wave bottom part AN (part AN2 in Fig. 5) of the fuel delivery pipe 5. The example shown in Fig. 8 is the analysis result for a V-type engine 1, and the vibration mode of the cylinder head cover 3 on the right bank side to which the union bolt 9 is attached is shown by a solid line, and the vibration mode of the cylinder head cover 3 on the left bank side is shown by a dashed line. For comparison, the union bolt 9 as a damper mass is not attached to the fuel delivery pipe 5 on the left bank side.

[0043] As shown in FIG. 8, when an excitation force is applied to each of the left and right fuel delivery pipes 5, the left and right cylinder head covers 3 to which the fuel delivery pipes 5 are attached vibrate. The left and right cylinder head covers 3 basically have the same vibration mode, but in the example shown in FIG. 8, differences appear depending on whether or not the union bolt 9 is present. That is, in the cylinder head cover 3 on the right bank side to which the union bolt 9 is attached as a damper mass, the inertance is reduced in the abnormal noise generation range between about 1.3 kHz and about 1.5 kHz. On the other hand, in the cylinder head cover 3 on the left bank side to which the union bolt 9 is not attached as a damper mass, no reduction in inertance is observed in the above abnormal noise generation range. Therefore, it can be seen that the vibration and noise suppression effect can be obtained by attaching an accessory part AP such as the union bolt 9 to the wave midpoint AN of the fuel delivery pipe 5 and making it function as a damper mass.

[0044] As described above, according to the fuel delivery structure for a direct injection engine in an embodiment of the present invention, it is possible to appropriately suppress the generation of abnormal sounds and noises caused by fuel pressure pulsation in the fuel delivery pipe 5 without using any special parts or members, by utilizing existing accessories AP, i.e., without incurring any increase in costs. [Explanation of symbols]

[0045] 1. Direct injection engine (center injection type direct injection engine) 2. Cylinder head 3 Cylinder head cover 3a Injector arrangement hole (formed in the cylinder head cover) 3b Boss for fastening bolt (formed on cylinder head cover) 3c Spark plug hole (formed in the cylinder head cover) 3d Bolt holes (formed in the cylinder head cover) 4 Injectors 4a (Injector) Body (Nozzle Holder) 4b (Top end of injector) 4c (injector) nozzle 4d (Injector) Nozzle Holder Clamp 5 Fuel delivery pipe 5a (Fuel delivery pipe) main section 5b Injector mounting part (of fuel delivery pipe) 5c (Fuel delivery pipe) Boss for fastening bolt 5d (Fuel delivery pipe) bolt hole (through hole) 6 Fuel pressure sensor (pressure sensor: accessory part) 7 Fastening bolts 8 Wire harness (electric wire: accessory part) 9 Union bolt (joint material: accessory part) 10 Fuel Hose AP Accessories AN, AN1, AN2 wave abdomen (where accessories are attached)

Claims

1. A fuel delivery structure for a cylinder injection engine comprising: a cylinder head; a cylinder head cover attached to the cylinder head and covering an upper surface of the cylinder head; an injector for injecting fuel into a combustion chamber of the cylinder head; and a fuel delivery pipe for supplying the fuel to the injector by pressure transfer, the fuel being directly injected into the combustion chamber and burned by spark ignition, The cylinder injection engine includes an accessory that is involved in the structure or operation of the cylinder injection engine, The fuel delivery pipe is The injector has a wave bottom where the amplitude or displacement of the vibration caused by the injection of the fuel is maximized or where the amplitude or displacement is relatively large, The attachment is attached to the wave bottom. A fuel delivery structure for a direct injection engine.

2. 2. A fuel delivery structure for a cylinder injection engine according to claim 1, The fuel delivery pipe is disposed so as to be connected to the injector directly above the injector and is fixed to the cylinder head cover. A fuel delivery structure for a direct injection engine.

3. 3. A fuel delivery structure for a cylinder injection engine according to claim 2, The injector is disposed immediately above the cylinder head cover and the combustion chamber. A fuel delivery structure for a direct injection engine.

4. A fuel delivery structure for a cylinder injection engine according to any one of claims 1 to 3, The accessory is a pressure sensor that detects the pressure of the fuel. A fuel delivery structure for a direct injection engine.

5. A fuel delivery structure for a cylinder injection engine according to any one of claims 1 to 3, The accessory is a joint member that connects the fuel delivery pipe and a fuel hose that supplies the fuel to the fuel delivery pipe. A fuel delivery structure for a direct injection engine.

6. A fuel delivery structure for a cylinder injection engine according to any one of claims 1 to 3, The accessory is an electric wire connected to an electrical component of the direct injection engine. A fuel delivery structure for a direct injection engine.

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