JP7295361B2 - fuel injection system - Google Patents

Description

The present invention relates to a fuel injection system for injecting fuel into combustion chambers of an engine.

Patent Literature 1 discloses an internal combustion engine with a common rail. The common rail disclosed in Patent Document 1 is fixed to the lower portion of the head cover via two mounting portions integrally formed with the cylindrical body of the common rail, and supplies high-pressure fuel to the injectors. The injector disclosed in Patent Literature 1 is attached to a cylinder head and injects high-pressure fuel supplied from a common rail into the cylinder. In the internal combustion engine described in Patent Document 1, the common rail and the injector are connected to each other by a fuel pipe.

However, if the common rail and the injector are connected to each other by a fuel pipe, there is a problem that pressure loss of fuel occurs in the fuel pipe. Moreover, when the fuel pipe is arranged, there is a problem that the number of parts increases. Further, as described above, the common rail described in Patent Document 1 has two mounting portions that are integrally formed with the cylindrical body of the common rail, and is fixed to the lower portion of the head cover via the two mounting portions. . Therefore, there is a problem that the structure of the common rail becomes complicated and large. On the other hand, if the common rail does not have a mounting portion, a member such as a bracket is required to fix the common rail, resulting in an increase in the number of parts. Also, a member such as a bracket may be required for fixing the injector.

On the other hand, there are fuel injection systems in which injectors are directly connected to a common rail without intervening a fuel pipe. As a result, the number of fuel pipes can be reduced, the occurrence of fuel pressure loss can be suppressed, and the number of parts can be reduced. However, in a fuel injection system in which the injector is directly connected to the common rail without a fuel pipe, depending on the fixing structure of the common rail and injector, the strength of the fuel injection system may be reduced and vibration and noise may be amplified. .

Japanese Patent No. 6468687

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and provides a fuel injection system capable of suppressing the occurrence of fuel pressure loss, reducing the number of parts, and reducing vibration and noise. for the purpose.

The above-mentioned problem is a fuel injection system for injecting fuel into a combustion chamber of an engine. a fuel pressure accumulator for accumulating pressure; and an injector directly connected to the fuel pressure accumulator and mounted on the cylinder head for injecting the fuel supplied from the fuel pressure accumulator into the combustion chamber, wherein the fuel The pressure accumulator is fixed to the bracket using a first fastening member, the bracket is fixed to the cylinder head using a second fastening member, the first fixing portion meshing with the first fastening member; 2. It is formed in a ladder-like or grid-like shape, having a second fixing part having a hole through which a fastening member passes, and a reinforcing part for connecting and reinforcing the first fixing part and the second fixing part which are adjacent to each other. It is solved by the fuel injection system according to the present invention characterized by:

According to the fuel injection system of the present invention, the fuel pressure accumulator that accumulates fuel supplied from the fuel pump is supported and fixed to the bracket that is fixed to the cylinder head of the engine. An injector for injecting fuel supplied from the fuel pressure accumulator into the combustion chamber of the engine is directly connected to the fuel pressure accumulator and mounted on the cylinder head. In this way, since the injector is directly connected to the fuel pressure accumulator, the occurrence of fuel pressure loss can be suppressed, and the number of parts such as fuel pipes and injector fixing brackets can be reduced.

Here, the fuel pressure accumulator is fixed to the bracket using the first fastening member. The bracket is fixed to the cylinder head using a second fastening member. The bracket that supports the fuel accumulator to which the injector is directly connected includes a first fixing portion that engages with the first fastening member, a second fixing portion that has a hole through which the second fastening member passes, and a second fixing portion that is adjacent to each other. It has a reinforcing portion that connects and reinforces the first fixing portion and the second fixing portion, and is formed in a ladder shape or a lattice shape. As a result, the fuel injection system according to the present invention can reinforce the fixing structure of the fuel pressure accumulator and the injector using the ladder-like or grid-like bracket. The ladder-like or lattice-like bracket increases the strength of the fixing structure of the fuel pressure accumulator and the injector, so that vibrations occurring in the fuel injection system can be reduced. Moreover, since the vibration generated in the fuel injection system can be reduced, the noise generated in the fuel injection system can be reduced. As a result, the fuel injection system according to the present invention can suppress the occurrence of fuel pressure loss, reduce the number of parts, and reduce vibration and noise.

In the fuel injection system according to the present invention, preferably, the reinforcing portion is a first reinforcing portion, and the bracket includes a second reinforcing portion that connects and reinforces the adjacent first fixing portions, and a second reinforcing portion that connects and reinforces the adjacent first fixing portions. and a third reinforcing portion that connects and reinforces the matching second fixing portions.

According to the fuel injection system of the present invention, the bracket includes the first reinforcing portion that connects and reinforces the first fixing portion and the second fixing portion that are adjacent to each other, and the first reinforcing portion that connects and reinforces the first fixing portions that are adjacent to each other. and a third reinforcing portion that connects and reinforces the second fixing portions adjacent to each other, and is formed in a ladder shape or a lattice shape. Therefore, the strength of the fixing structure for the fuel pressure accumulator and the injector is further improved. Therefore, the vibration generated in the fuel injection system can be further reduced. Moreover, since the vibration generated in the fuel injection system can be further reduced, the noise generated in the fuel injection system can be further reduced. As a result, the fuel injection system according to the present invention can suppress the occurrence of fuel pressure loss, reduce the number of parts, and further reduce vibration and noise.

In the fuel injection system according to the present invention, preferably, the first fastening member is engaged with the first fixing portion through a hole formed in the fuel pressure accumulator from above, and the second fastening member is preferably engaged with the first fixing portion from above. It is characterized by meshing with the cylinder head through the hole formed in the second fixing part.

According to the fuel injection system of the present invention, the first fastening member meshes with the first fixing portion of the bracket from above through the hole formed in the fuel pressure accumulator. The second fastening member is engaged with the cylinder head from above through a hole formed in the second fixing portion of the bracket. Therefore, when performing the work of assembling and fixing the bracket to the cylinder head, the operator engages the second fastening member from above with the cylinder head through the hole formed in the second fixing portion of the bracket, and attaches the bracket to the cylinder head. It can be easily fastened. Further, when the worker assembles and fixes the fuel pressure accumulator to which the injector is directly connected to the bracket, the operator inserts the first fastening member from above through the hole formed in the fuel pressure accumulator. It is possible to easily fasten the fuel pressure accumulator to which the injector is directly connected. As a result, the fuel injection system according to the present invention can facilitate assembly and improve workability.

In the fuel injection system according to the present invention, preferably, a fastening surface of the fuel pressure accumulator that contacts and is fastened to the bracket is a positioning surface of the fuel pressure accumulator that contacts the injector and determines the position of the injector. It is characterized by having the same surface.

According to the fuel injection system of the present invention, the fastening surface of the fuel pressure accumulator that contacts and is fastened to the bracket is the same surface as the positioning surface of the fuel pressure accumulator that contacts the injector and determines the position of the injector. As a result, the fuel injection system according to the present invention can be easily assembled and improved in workability, and the fuel pressure accumulator directly connected to the injector can be stably fixed to the bracket. be able to.

In the fuel injection system according to the present invention, preferably, at least one of the fuel pressure accumulator and the bracket has a guide member that guides the injector to a mounting position on the cylinder head.

According to the fuel injection system of the present invention, at least one of the fuel pressure accumulator and the bracket has a guide member that guides the injector to the mounting position of the cylinder head. Therefore, when the fuel pressure accumulator is assembled and fixed to the bracket, even if the position of the injector with respect to the cylinder head is not determined, the fuel pressure accumulator guides the injector to the mounting position on the cylinder head by the guide member. It is attached and fixed to the bracket while As a result, the fuel injection system according to the present invention, when the fuel pressure accumulator is assembled and fixed to the bracket, and when the injector is mounted on the cylinder head, the injector connected to the fuel pressure accumulator is subjected to bending load and the like. It is possible to suppress the addition and suppress the distortion of the injector.

In addition, since the fuel pressure accumulator is assembled and fixed to the bracket while guiding the injector to the mounting position of the cylinder head by the guide member, no special jig or special tool is required. As a result, the fuel injection system according to the present invention can suppress an increase in the number of processes in the process of assembling the fuel pressure accumulator to the bracket and the process of assembling the injector to the cylinder head. Moreover, the fuel injection system according to the present invention can eliminate the need for special jigs and special tools for after-sales maintenance in the market.

In the fuel injection system according to the present invention, preferably, the guide member includes a protrusion provided on one of the fuel pressure accumulator and the bracket, and a protrusion provided on the other of the fuel pressure accumulator and the bracket. and a concave portion into which the convex portion is fitted.

According to the fuel injection system of the present invention, the guide member can more reliably guide the injector to the mounting position of the cylinder head by fitting the convex portion into the concave portion. That is, the guide member is used as an insertion guide when the fuel pressure accumulator is attached to the bracket and when the injector is attached to the cylinder head. Therefore, when the fuel pressure accumulator is assembled and fixed to the bracket, even if the position of the injector with respect to the cylinder head is not determined, the fuel pressure accumulator allows the injector to be securely positioned on the cylinder head by the guide member. can guide you to As a result, the fuel injection system according to the present invention, when the fuel pressure accumulator is assembled and fixed to the bracket, and when the injector is mounted on the cylinder head, the injector connected to the fuel pressure accumulator is subjected to bending load and the like. It is possible to further suppress the application of the force, thereby further suppressing the distortion of the injector.

In the fuel injection system according to the present invention, preferably, the injector is attached to the cylinder head by being inserted into an insertion hole formed in the cylinder head, and the direction in which the projection fits into the recess is It is characterized by being parallel to the direction in which the injector is inserted into the insertion hole.

According to the fuel injection system of the present invention, the direction in which the projection fits into the recess is parallel to the direction in which the injector is inserted into the insertion hole. Therefore, the direction in which the fuel pressure accumulator is assembled and fixed to the bracket is parallel to the direction in which the injector is inserted into the insertion hole. Therefore, the fuel accumulator is assembled and fixed to the bracket while guiding the injector to the mounting position of the cylinder head by the guide member while proceeding in parallel with the direction in which the injector is inserted into the insertion hole. As a result, the fuel injection system according to the present invention, when the fuel pressure accumulator is assembled and fixed to the bracket, and when the injector is mounted on the cylinder head, the injector connected to the fuel pressure accumulator is subjected to bending load and the like. It is possible to further suppress the application of the force, thereby further suppressing the distortion of the injector.

In the fuel injection system according to the present invention, preferably, the cylinder head has a sleeve that is press-fitted into the insertion hole and determines an insertion position of the injector with respect to the insertion hole.

According to the fuel injection system of the present invention, the sleeve that determines the insertion position of the injector with respect to the insertion hole into which the injector is inserted is press-fitted into the insertion hole into which the injector is inserted. Therefore, the sleeve can determine the position of the injector more accurately and can prevent the sleeve itself from rotating in the insertion hole. As a result, the fuel injection system according to the present invention can improve the durability and reliability of the injector.

In the fuel injection system according to the present invention, preferably, the guide member has a plurality of projections and a plurality of recesses into which the plurality of projections are fitted.

According to the fuel injection system of the present invention, the guide member has a plurality of protrusions and a plurality of recesses. Each of the plurality of protrusions fits into each of the plurality of recesses. Therefore, the guide member is used as an insertion guide at a plurality of positions when the fuel pressure accumulator is assembled to the bracket and when the injector is attached to the cylinder head. Therefore, the fuel pressure accumulator is assembled and fixed to the bracket while guiding the injector to the mounting position of the cylinder head at a plurality of positions by the guide member. As a result, the fuel injection system according to the present invention can further suppress the bending load and the like from being applied to the injector connected to the fuel pressure accumulator without using a special jig or a special tool, and the injector will not be distorted. What happens can be further suppressed.

In the fuel injection system according to the present invention, preferably, when the injector is attached to the cylinder head, the projection begins to fit into the recess before the position of the injector with respect to the cylinder head is determined. and

According to the fuel injection system according to the present invention, when the injector is mounted on the cylinder head, the guide member can start guiding the injector to the mounted position on the cylinder head before the position of the injector with respect to the cylinder head is determined. As a result, the fuel injection system according to the present invention, when the fuel pressure accumulator is assembled and fixed to the bracket, and when the injector is mounted on the cylinder head, the injector connected to the fuel pressure accumulator is subjected to bending load and the like. It is possible to further suppress the application of the force, thereby further suppressing the distortion of the injector.

According to the present invention, it is possible to provide a fuel injection system capable of suppressing pressure loss of fuel, reducing the number of parts, and reducing vibration and noise.

1 is a perspective view showing an engine equipped with a fuel injection system according to the invention; FIG. 1 is an exploded view showing an engine equipped with a fuel injection system according to this embodiment; FIG. 1 is an enlarged perspective view of a fuel injection system according to an embodiment; FIG. 4 is a plan view of the fuel injection system according to the present embodiment when viewed in the direction of arrow A11 shown in FIG. 3; FIG. It is a top view showing the bracket of this embodiment. 1 is a perspective view of a fuel injection system according to an embodiment when viewed obliquely from above; FIG. It is a top view showing the arrangement relationship between the bracket of this embodiment, and a cylinder head. It is a top view showing the cylinder head of this embodiment. FIG. 2 is a perspective view of the fuel pressure accumulator of the present embodiment when viewed obliquely from below;

Preferred embodiments of the invention are described in detail below with reference to the drawings.
Since the embodiments described below are preferred specific examples of the present invention, various technically preferable limitations are applied. Unless otherwise stated, the invention is not limited to these modes. Further, in each drawing, the same constituent elements are denoted by the same reference numerals, and detailed description thereof will be omitted as appropriate.

FIG. 1 is a perspective view showing an engine equipped with a fuel injection system according to the invention.
FIG. 2 is an exploded view showing an engine equipped with a fuel injection system according to this embodiment.
1 and 2, for convenience of explanation, parts provided below the cylinder head of the engine (for example, a cylinder block, a crankcase, etc.) are omitted. Further, in FIG. 2, the fuel pipe 61 is omitted for convenience of explanation.

The engine 2 shown in FIGS. 1 and 2 is, for example, an industrial diesel engine and is mounted on industrial machines such as construction machines, agricultural machines, and lawn mowers. The engine 2 is an in-line multi-cylinder engine, and in the example shown in FIGS. 1 and 2 is an in-line three-cylinder engine. The engine 2 is, for example, an auxiliary chamber type (IDI: Indirect Injection) diesel engine. However, the engine 2 according to this embodiment is not limited to an in-line three-cylinder engine. Also, the engine 2 according to the present embodiment is not limited to a pre-chamber type diesel engine.

The engine 2 includes a cylinder head 21 , a head cover 22 , an intake manifold 23 and a fuel injection system 3 . The fuel injection system 3 is provided above the cylinder head 21 . In the specification of the present application, the vertical direction corresponds to the vertical direction of an industrial machine such as a construction machine, an agricultural machine, or a lawnmower in which the engine 2 is mounted.

A fuel injection system 3 according to this embodiment includes a bracket 5 , a fuel pressure accumulator 6 , an injector 7 , and a harness 8 .

Bracket 5 is fixed to the upper portion of cylinder head 21 using a plurality of second fastening members 59 . In the fuel injection system 3 according to this embodiment, the bracket 5 is fixed to the cylinder head 21 using three second fastening members 59 . Specifically, the second fastening member 59 passes through a hole 521 (see FIG. 5) formed in the second fixing portion 52 (see FIG. 5) of the bracket 5 from above to below, and extends through the upper portion of the cylinder head 21. engages with a female thread 213 formed in the . Thereby, the bracket 5 is fastened to the cylinder head 21 using the plurality of second fastening members 59 . Details of the bracket 5 will be described later.

The fuel pressure accumulator 6 is a so-called common rail fuel injection device, and accumulates the pressure of fuel, which is pressurized by a fuel pump (not shown) and supplied through a fuel pipe 61, on a common rail. The fuel pressure accumulator 6 is fixed to the bracket 5 using a plurality of first fastening members 62 . In the fuel injection system 3 according to this embodiment, the fuel pressure accumulator 6 is fixed to the bracket 5 using three first fastening members 62 . Specifically, the first fastening member 62 passes through a hole 63 (see FIG. 9) provided in the fuel pressure accumulator 6 from above to below, and extends through a female screw formed in the first fixing portion 51 of the bracket 5. It meshes with 511. As a result, the fuel pressure accumulator 6 is fastened to the bracket 5 using the plurality of first fastening members 62 . In the bracket 5 shown in FIG. 2 , recesses 513 are formed in the upper portions of the female threads 511 in the two first fixing portions 51 at both ends of the three first fixing portions 51 . Details of the recess 513 will be described later.

The injector 7 is directly connected to the fuel pressure accumulator 6 as shown in FIG. As mentioned above, the engine 2 represented in FIGS. 1 and 2 is an in-line three-cylinder engine. Therefore, in the fuel injection system 3 according to this embodiment, the three injectors 7 are directly connected to the fuel pressure accumulator 6 and arranged side by side along the arrangement direction A1. Also, the injector 7 is mounted on the cylinder head 21 . Specifically, as shown in FIG. 2 , the lower portion of the injector 7 is inserted into the insertion hole 212 formed in the cylinder head 21 . In the engine 2 shown in FIG. 2, the sleeve 211 is press-fitted into the insertion hole 212 and fixed to the cylinder head 21 . Therefore, in the engine 2 shown in FIG. 2 , the hole provided in the sleeve 211 forms part of the insertion hole 212 . The sleeve 211 determines the insertion position of the injector 7 with respect to the insertion hole 212 . Note that the sleeve 211 may not necessarily be provided.

The harness 8 is connected to the injector 7 at a connection portion 81 called a coupler or the like, and supplies power to the injector 7 . For example, the injector 7 is electric power controlled by an electronic control unit (ECU) based on a detection signal regarding the engine speed and a detection signal regarding the accelerator opening, and supplied via the harness 8. , the needle valve is opened to inject the fuel supplied from the fuel pressure accumulator 6 into the combustion chamber 215 of the engine 2 (see FIGS. 7 and 8). For example, the combustion chamber 215 shown in FIGS. 7 and 8 is an auxiliary chamber provided in the cylinder head 21 (that is, an auxiliary combustion chamber). However, the combustion chamber into which the injector 7 of this embodiment injects fuel is not limited to the pre-chamber. Thus, the harness 8 is a harness for driving the injector 7, that is, a harness for driving the injector.

The harness 8 is held by a holding member 82 and fixed to the bracket 5 via the holding member 82 . Specifically, as shown in FIGS. 1 and 2 , the holding member 82 holds the harness 8 , and the protrusion 821 of the holding member 82 fits into the hole 531 formed in the third fixing portion 53 of the bracket 5 . It is attached to the bracket 5 by being inserted. Thereby, the harness 8 is fixed to the bracket 5 via the holding member 82 . As the holding member 82 , for example, a binding band attached to the outer circumference of the harness 8 to hold the harness 8 may be used. However, the harness 8 is not limited to the binding band.

FIG. 3 is an enlarged perspective view of the fuel injection system according to this embodiment.
FIG. 4 is a plan view when the fuel injection system according to this embodiment is viewed in the direction of arrow A11 shown in FIG.
FIG. 5 is a plan view showing the bracket of this embodiment.

First, with reference to FIG. 5, the details of the bracket of this embodiment will be described.
As shown in FIG. 5, the bracket 5 of this embodiment is formed in a ladder shape or lattice shape. Specifically, the bracket 5 includes a first fixing portion 51, a second fixing portion 52, a third fixing portion 53, a first reinforcing portion 541, a second reinforcing portion 542, and a third reinforcing portion 543. , have

The first fixing portion 51 has a female thread 511 that meshes with the male thread of the first fastening member 62 . As shown in FIG. 5 , the bracket 5 of this embodiment has three first fixing portions 51 . The three first fixing portions 51 are arranged side by side along the arrangement direction A1 of the three injectors 7 . As shown in FIG. 5 , recesses 513 are formed in the upper portions of female threads 511 in two of the three first fixing portions 51 at both ends. The recessed portion 513 forms part of the “guide member” of the present invention and has an inner peripheral surface parallel to the inserting direction of the injector 7 and the traveling direction of the first fastening member 62 . In other words, the axis of the recess 513 is parallel to the inserting direction of the injector 7 and the traveling direction of the first fastening member 62 .

Note that the concave portions 513 are not limited to being formed in the two first fixing portions 51 at both ends of the three first fixing portions 51, and are formed corresponding to the convex portions 64 (see FIG. 3). It is good if it is. For example, the recessed portion 513 may be formed above the female thread 511 in all three first fixing portions 51 . Moreover, it is desirable that the concave portion 513 is formed in at least two of the three first fixing portions 51 in order to further improve the guiding accuracy and the positioning accuracy in the horizontal direction. For example, the concave portion 513 may be formed above the female thread 511 in the center first fixing portion 51 and the first fixing portion 51 at either end of the three first fixing portions 51 . Further, the recess 513 may be formed corresponding to the projection 64, may not necessarily be formed above the female thread 511, and may not be formed coaxially with the axis of the female thread 511. good.

The second fixing portion 52 has a hole 521 through which a male screw of the second fastening member 59 can pass. As shown in FIG. 5 , the bracket 5 of this embodiment has three second fixing portions 52 . The three second fixing portions 52 are arranged side by side along the arranging direction A1 of the three injectors 7, and extend from the three first fixing portions 51 in a direction intersecting the arranging direction A1 of the three injectors 7. placed apart.

The third fixing portion 53 has a hole 531 into which the protrusion 821 of the holding member 82 can be inserted. As shown in FIG. 5 , the bracket 5 of this embodiment has three third fixing portions 53 . The three third fixing portions 53 are arranged side by side along the arrangement direction A1 of the three injectors 7, and extend from the three first fixing portions 51 in a direction intersecting the arrangement direction A1 of the three injectors 7. placed apart. Also, the third fixing portion 53 is provided in the vicinity of the second fixing portion 52 .

The first reinforcing portion 541 connects the first fixing portion 51 and the second fixing portion 52 adjacent to each other and reinforces the bracket 5 . The second reinforcing portion 542 connects the first fixing portions 51 adjacent to each other and reinforces the bracket 5 . The third reinforcing portion 543 connects the second fixing portions 52 adjacent to each other and reinforces the bracket 5 .
The bracket 5 of this embodiment has the structure described above and is formed in a ladder shape or a grid shape.

Next, assembly of the bracket 5 and the fuel pressure accumulator 6 will be described with reference to FIGS. 3 and 4. FIG.
1 and 2, the injector 7 of this embodiment is directly connected to the fuel pressure accumulator 6. As shown in FIG. As shown in FIGS. 3 and 4, when the fuel pressure accumulator 6 is fastened to the bracket 5 using the first fastening member 62, the injector 7 is attached to, for example, an O-ring (not shown). It is held in advance in the insertion hole 66 (see FIG. 9) of the fuel pressure accumulator 6 by means such as .

As shown in FIG. 4, a biasing member 72 such as a leaf spring is attached to the injector 7 . When the injector 7 is attached to the cylinder head 21 (see FIGS. 1 and 2), the biasing member 72 applies biasing force to the fuel pressure accumulator 6 and the cylinder head 21 . As shown in FIG. 4 , in a state before the injector 7 is attached to the cylinder head 21 and the injector 7 is held in the insertion hole 66 of the fuel pressure accumulator 6, the injector 7 is attached to the fuel pressure accumulator It is in a state of floating slightly from 6. That is, the position of the injector 7 with respect to the fuel pressure accumulator 6 is not fixed. Also, the position of the injector 7 with respect to the cylinder head 21 is not determined. After that, when the fuel pressure accumulator 6 is fastened to the bracket 5 using the first fastening member 62 , the injector 7 is engaged with the fuel pressure accumulator 6 while the biasing member 72 applies a biasing force to the fuel pressure accumulator 6 and the cylinder head 21 . and the cylinder head 21. At this time, the position of the injector 7 relative to the fuel pressure accumulator 6 and the cylinder head 21 is determined.

Here, when the fuel pressure accumulator 6 is fastened to the bracket 5 using the first fastening member 62 in a state where the injector 7 is held by the fuel pressure accumulator 6 and the position of the injector 7 is not determined. For example, a bending load may be applied to the injector 7 directly connected to the fuel pressure accumulator 6 . If a bending load or the like is applied to the injector 7, the injector 7 may be distorted. If the injector 7 is distorted, the position of the injector 7 may deviate from the designed position, which may affect the fuel injection amount. The fuel injection amount of the injector 7 affects the performance of the engine 2 and exhaust gas performance. Therefore, it is desirable that the injector 7 be assembled while maintaining the designed posture.

In contrast, in the fuel injection system 3 according to the present embodiment, the fuel pressure accumulator 6 has a convex portion 64 as shown in FIGS. 3 and 4 . The convex portion 64 constitutes a part of the "guide member" of the present invention, like the concave portion 513 described above. That is, the “guide member” of the present invention has the convex portion 64 and the concave portion 513 . The protrusion 64 is formed corresponding to the recess 513 and fits into the recess 513 . In other words, the concave portion 513 is formed corresponding to the convex portion 64 and is fitted to the convex portion 64 .

The convex portion 64 may be provided on the fuel pressure accumulator 6 or may be provided on the bracket 5 . That is, the convex portion 64 is provided on either one of the fuel pressure accumulator 6 and the bracket 5 . Recess 513 may be provided in fuel pressure accumulator 6 or may be provided in bracket 5 . In other words, recess 513 is provided in the other of fuel pressure accumulator 6 and bracket 5 . In the example shown in FIGS. 3 and 4 , the convex portion 64 is provided in the fuel pressure accumulator 6 and the concave portion 513 is provided in the bracket 5 .

For example, the protrusion 64 is a pipe pin that fits into the recess 513 . In the example shown in FIGS. 3 and 4, the pipe pin as the convex portion 64 is formed in a hollow rod shape having an inner diameter through which the male screw of the first fastening member 62, for example, can pass. The outer peripheral surface of one end of the projection 64 is press-fitted into the hole 63 (see FIG. 9) of the fuel pressure accumulator 6 and fixed, and the outer peripheral surface of the other end of the projection 64 fits into the recess 513 formed in the bracket 5 . fits. In addition, as described above, the bracket 5 may have the convex portion 64 . In this case, the outer peripheral surface of one end of the projection 64 is press-fitted into the recess 513 of the bracket 5 and fixed, and the outer peripheral surface of the other end of the projection 64 is the hole 63 of the fuel pressure accumulator 6 (that is, the recess). fit in. In the following description, the case where the fuel pressure accumulator 6 has the convex portion 64 and the bracket 5 has the concave portion 513 will be taken as an example.

Note that the convex portion 64 is not limited to being a pipe pin. The convex portion 64 may have a shape that fits in the concave portion 513, and may be a solid rod-like member. For example, protrusion 64 may be a sleeve or a collar. The vertical cross-sectional shape of the convex portion 64 is not particularly limited.

As shown in FIG. 3, in the fuel injection system 3 according to this embodiment, a plurality of projections 64 are provided. Specifically, as shown in FIG. 3 , two protrusions 64 are fixed to two holes 63 at both ends of the three holes 63 of the fuel pressure accumulator 6 . Each of the two protrusions 64 fits into each of the two recesses 513 formed in the bracket 5 .

It should be noted that, similarly to the case described above regarding the recessed portion 513 , the projecting portion 64 is not limited to being fixed to the two holes 63 at both ends of the three holes 63 of the fuel pressure accumulator 6 . It is sufficient if they are provided correspondingly. For example, the protrusions 64 may be fixed to all three holes 63 of the fuel pressure accumulator 6 . Moreover, it is desirable that the convex portion 64 is fixed to at least two of the three holes 63 of the fuel pressure accumulator 6 in order to further improve the guiding accuracy and positioning accuracy in the horizontal direction. For example, the convex portion 64 may be fixed to the central hole 63 and the holes 63 at either end of the three holes 63 of the fuel pressure accumulator 6 .

As shown in FIG. 4 , the convex portion 64 is fixed to the hole 63 of the fuel pressure accumulator 6 while protruding from the fastening surface 631 (see FIG. 9 ) of the fuel pressure accumulator 6 . Here, when the injector 7 is inserted into the insertion hole 212 of the cylinder head 21 and attached to the cylinder head 21, the projection 64 is fitted into the recess 513 of the bracket 5 before the position of the injector 7 with respect to the cylinder head 21 is determined. start to get stuck. In the fuel injection system 3 according to this embodiment, the injector 7 is inserted into the insertion hole 212 of the cylinder head 21 , and the positioning surface 71 of the injector 7 contacts the positioning surface 214 of the cylinder head 21 . The position of 7 is determined.

Specifically, as shown in FIG. 4, when the injector 7 is inserted into the insertion hole 212 of the cylinder head 21, the tip 641 of the protrusion 64 and the fastening surface 512 of the bracket 5 (that is, the recess 513 of the bracket 5 ) is shorter than the distance D2 between the positioning surface 71 of the injector 7 and the positioning surface 214 of the cylinder head 21 (that is, the entrance surface of the insertion hole 212 of the cylinder head 21). Therefore, when the injector 7 is inserted into the insertion hole 212 of the cylinder head 21 , the projection 64 fits into the recess 513 of the bracket 5 before the positioning surface 71 of the injector 7 contacts the positioning surface 214 of the cylinder head 21 . start. Thereby, the projection 64 and the recess 513 can start guiding the injector 7 to the mounting position of the cylinder head 21 before the position of the injector 7 with respect to the cylinder head 21 is determined.

Further, as described above, the recessed portion 513 has an inner peripheral surface parallel to the inserting direction of the injector 7 into the inserting hole 212 of the cylinder head 21 . In other words, the axis of the recess 513 is parallel to the direction in which the injector 7 is inserted into the insertion hole 212 of the cylinder head 21 . Therefore, the direction in which the projection 64 fits into the recess 513 is parallel to the direction in which the injector 7 is inserted into the insertion hole 212 of the cylinder head 21 . Therefore, the direction in which the fuel pressure accumulator 6 is assembled and fixed to the bracket 5 is parallel to the direction in which the injector 7 is inserted into the insertion hole 212 of the cylinder head 21 .

As a result, the fuel pressure accumulator 6 guides the injector 7 to the mounting position of the cylinder head 21 by means of the protrusion 64 and the recess 513 , and advances parallel to the inserting direction of the injector 7 into the insertion hole 212 of the cylinder head 21 . assembled and fixed to the In this manner, the guide member having the convex portion 64 and the concave portion 513 can more reliably guide the injector 7 to the mounting position of the cylinder head 21 by fitting the convex portion 64 into the concave portion 513 . That is, when the fuel pressure accumulator 6 is attached to the bracket 5 and the injector 7 is attached to the cylinder head 21, the guide member having the convex portion 64 and the concave portion 513 is used as an insertion guide.

As described above, according to the fuel injection system 3 according to the present embodiment, the fuel pressure accumulator 6 that accumulates fuel supplied from the fuel pump is supported by the bracket 5 fixed to the cylinder head 21 of the engine 2. It is fixed as soon as An injector 7 for injecting fuel supplied from the fuel pressure accumulator 6 into a combustion chamber 215 (see FIGS. 7 and 8) of the engine 2 is directly connected to the fuel pressure accumulator 6 and mounted on the cylinder head 21. be done. Here, at least one of the fuel pressure accumulator 6 and the bracket 5 (in this embodiment, both the fuel pressure accumulator 6 and the bracket 5) is a guide member (the projection 64 and It has a recess 513). Therefore, when the fuel pressure accumulator 6 is assembled and fixed to the bracket 5 , even if the position of the injector 7 with respect to the cylinder head 21 is not determined, the fuel pressure accumulator 6 can be The injector 7 is assembled and fixed to the bracket 5 while guiding the injector 7 to the mounting position of the cylinder head 21 . Thus, the fuel injection system 3 according to the present embodiment is connected to the fuel pressure accumulator 6 when the fuel pressure accumulator 6 is assembled and fixed to the bracket 5 and when the injector 7 is attached to the cylinder head 21. Therefore, it is possible to suppress the bending load or the like from being applied to the injector 7 , thereby suppressing the distortion of the injector 7 .

Further, since the fuel pressure accumulator 6 is assembled and fixed to the bracket 5 while guiding the injector 7 to the mounting position of the cylinder head 21 by the projection 64 and the recess 513, no special jig or special tool is required. As a result, the fuel injection system 3 according to the present embodiment can suppress an increase in the number of processes in the process of assembling the fuel pressure accumulator 6 to the bracket 5 and the process of assembling the injector 7 to the cylinder head 21 . Moreover, the fuel injection system 3 according to the present embodiment can eliminate the need for special jigs and special tools for after-sales maintenance in the market.

Further, the guide member having the convex portion 64 and the concave portion 513 can reliably guide the injector 7 to the mounting position of the cylinder head 21 by fitting the convex portion 64 into the concave portion 513 . That is, when the fuel pressure accumulator 6 is attached to the bracket 5 and the injector 7 is attached to the cylinder head 21, the guide member having the convex portion 64 and the concave portion 513 is used as an insertion guide. Therefore, when the fuel pressure accumulator 6 is assembled and fixed to the bracket 5 , even if the position of the injector 7 with respect to the cylinder head 21 is not determined, the fuel pressure accumulator 6 can be The injector 7 can be reliably guided by the mounting position of the cylinder head 21. - 特許庁Thus, the fuel injection system 3 according to the present embodiment is connected to the fuel pressure accumulator 6 when the fuel pressure accumulator 6 is assembled and fixed to the bracket 5 and when the injector 7 is attached to the cylinder head 21. The bending load or the like applied to the injector 7 can be further suppressed, and the distortion of the injector 7 can be further suppressed.

The direction in which the projection 64 fits into the recess 513 is parallel to the direction in which the injector 7 is inserted into the insertion hole 212 of the cylinder head 21 . Therefore, the direction in which the fuel pressure accumulator 6 is assembled and fixed to the bracket 5 is parallel to the direction in which the injector 7 is inserted into the insertion hole 212 of the cylinder head 21 . Therefore, the fuel pressure accumulator 6 guides the injector 7 to the mounting position of the cylinder head 21 by means of the convex portion 64 and the concave portion 513 , and advances in parallel with the inserting direction of the injector 7 into the insertion hole 212 of the cylinder head 21 to reach the bracket 5 . assembled and fixed. Thus, the fuel injection system 3 according to the present embodiment is connected to the fuel pressure accumulator 6 when the fuel pressure accumulator 6 is assembled and fixed to the bracket 5 and when the injector 7 is attached to the cylinder head 21. The bending load or the like applied to the injector 7 can be further suppressed, and the distortion of the injector 7 can be further suppressed.

The guide member also has a plurality of protrusions 64 and a plurality of recesses 513 . Each of the plurality of protrusions 64 fits into each of the plurality of recesses 513 . Therefore, the plurality of protrusions 64 and the plurality of recesses 513 are used as insertion guides at a plurality of positions when the fuel pressure accumulator 6 is assembled to the bracket 5 and when the injector 7 is attached to the cylinder head 21. . Therefore, the fuel accumulator 6 is assembled and fixed to the bracket 5 while guiding the injector 7 to the mounting position of the cylinder head 21 at a plurality of positions by the plurality of projections 64 and the plurality of recesses 513 . As a result, the fuel injection system 3 according to the present embodiment can further suppress bending load or the like from being applied to the injector 7 connected to the fuel pressure accumulator 6 without using a special jig or a special tool. It is possible to further suppress the distortion of the injector 7 .

Further, when the injector 7 is mounted on the cylinder head 21, the projection 64 and the recess 513 can start guiding the injector 7 to the mounting position of the cylinder head 21 before the position of the injector 7 with respect to the cylinder head 21 is determined. . Thus, the fuel injection system 3 according to the present embodiment is connected to the fuel pressure accumulator 6 when the fuel pressure accumulator 6 is assembled and fixed to the bracket 5 and when the injector 7 is attached to the cylinder head 21. The bending load or the like applied to the injector 7 can be further suppressed, and the distortion of the injector 7 can be further suppressed.

Furthermore, since the injector 7 is directly connected to the fuel pressure accumulator 6, the occurrence of fuel pressure loss can be suppressed, and the number of parts such as fuel pipes and injector fixing brackets can be reduced. Here, the bracket 5 that supports the fuel pressure accumulator 6 to which the injector 7 is directly connected has a first fixing portion 51 that meshes with the first fastening member 62 and a second fastening member 521 having a hole 521 through which the second fastening member 59 passes. It has the fixing part 52 and the first reinforcing part 541 that connects and reinforces the first fixing part 51 and the second fixing part 52 adjacent to each other, and is formed in a ladder shape or a lattice shape. As a result, the fuel injection system 3 according to the present embodiment can reinforce the fixing structure of the fuel pressure accumulator 6 and the injector 7 by using the ladder-like or grid-like bracket 5 . The ladder-like or lattice-like bracket 5 improves the strength of the fixing structure of the fuel pressure accumulator 6 and the injector 7, so that vibrations occurring in the fuel injection system 3 can be reduced. Moreover, since the vibration generated in the fuel injection system 3 can be reduced, the noise generated in the fuel injection system 3 can be reduced. As a result, the fuel injection system 3 according to the present embodiment can suppress the occurrence of fuel pressure loss, reduce the number of parts, and reduce vibration and noise.

The bracket 5 also includes a first reinforcing portion 541 that connects and reinforces the first fixing portion 51 and the second fixing portion 52 that are adjacent to each other, and a second reinforcing portion that connects and reinforces the first fixing portions 51 that are adjacent to each other. It has a portion 542 and a third reinforcing portion 543 that connects and reinforces the second fixing portions 52 adjacent to each other, and is formed in a ladder shape or lattice shape. Therefore, the strength of the fixing structure for the fuel pressure accumulator 6 and the injector 7 is further improved. Therefore, the vibration generated in the fuel injection system 3 can be further reduced. In addition, since the vibration generated in the fuel injection system 3 can be further reduced, the noise generated in the fuel injection system 3 can be further reduced. As a result, the fuel injection system 3 according to this embodiment can suppress the occurrence of fuel pressure loss, reduce the number of parts, and further reduce vibration and noise.

Also, the first fastening member 62 meshes with the first fixing portion 51 of the bracket 5 from above through a hole 63 formed in the fuel pressure accumulator 6 . The second fastening member 59 meshes with the cylinder head 21 from above through a hole 521 formed in the second fixing portion 52 of the bracket 5 . Therefore, when the operator performs the work of assembling and fixing the bracket 5 to the cylinder head 21 , the second fastening member 59 is engaged with the cylinder head 21 through the hole 521 from above to easily fasten the bracket 5 to the cylinder head 21 . can be made Further, when the operator assembles and fixes the fuel pressure accumulator 6 to which the injector 7 is directly connected to the bracket 5 , the first fastening member 62 is passed through the hole 63 of the fuel pressure accumulator 6 from above to the bracket 5 . , and the fuel pressure accumulator 6 to which the injector 7 is directly connected can be easily fastened to the bracket 5 . As a result, the fuel injection system 3 according to this embodiment can be easily assembled and improved in workability.

A sleeve 211 for determining the insertion position of the injector 7 with respect to the insertion hole 212 into which the injector 7 is inserted is press-fitted into the insertion hole 212 of the cylinder head 21 . Therefore, the sleeve 211 can position the injector 7 more accurately and prevent the sleeve 211 itself from rotating in the insertion hole 212 . As a result, the fuel injection system 3 according to this embodiment can improve the durability and reliability of the injector 7 .

FIG. 6 is a perspective view of the fuel injection system according to the present embodiment when viewed obliquely from above.
As described above with reference to FIGS. 1 and 2 , the harness 8 is connected to the injector 7 at the connecting portion 81 called a coupler or the like and fixed to the bracket 5 via the holding member 82 . As shown in FIG. 6 , the harness 8 is fixed to the third fixing portion 53 of the bracket 5 at a position adjacent to the connecting portion 81 . Specifically, the harness 8 extends along the arrangement direction A1 of the plurality of injectors 7 and is fixed to the third fixing portion 53 of the bracket 5 at a position between the plurality of injectors 7 adjacent to each other. .

Here, if the harness for driving the injector is fixed to the head cover 22 (see FIG. 1), the fuel pipe 61, or the like, vibrations of the cylinder head 21, the fuel pipe 61, etc. may be transmitted to the harness, and the vibration of the harness may be amplified. There is Amplification of the vibration of the harness may reduce the durability of the harness or increase noise. Further, if the harness for driving the injector is fixed to, for example, a stay for fixing the harness, the number of parts increases.

In contrast, according to the fuel injection system 3 according to the present embodiment, the harness 8 (that is, the harness for driving the injector) is connected to the injector 7 and fixed to the bracket 5 . The bracket 5 is fixed to the cylinder head 21 as described above with respect to FIGS. Also, the fuel pressure accumulator 6 is fixed to a bracket 5 fixed to the cylinder head 21 and directly connected to the injector 7 . Therefore, the portion where the harness 8 is connected to the injector 7 and the portion where the harness 8 is fixed to the bracket form the same vibration system via the bracket 5, the fuel pressure accumulator 6, and the injector 7 with each other. Thereby, the fuel injection system 3 according to this embodiment can suppress the vibration of the harness 8 for driving the injector. In addition, since the vibration of the harness 8 is suppressed, the fuel injection system 3 according to the present embodiment suppresses disconnection and deterioration of the connection portion 81 of the harness 8, suppresses deterioration of the durability of the harness 8, and increases noise. can refrain from doing Further, the harness 8 is fixed to the bracket 5 that supports the fuel pressure accumulator 6 rather than a special part for fixing the harness. Therefore, the fuel injection system 3 according to this embodiment can suppress vibration of the harness 8 for driving the injector while suppressing an increase in the number of parts.

Also, the harness 8 is fixed to the bracket 5 at a position adjacent to the connecting portion 81 connected to the injector 7 . Therefore, the portion where the harness 8 is fixed to the bracket 5 can support the harness 8 at a position near the connecting portion 81 between the harness 8 and the injector 7 . As a result, the fuel injection system 3 according to this embodiment can further suppress the vibration of the harness 8 for driving the injector.

The harness 8 extends along the arrangement direction A1 of the plurality of injectors 7 and is fixed to the bracket 5 at positions between the plurality of injectors 7 adjacent to each other. Therefore, the portion where the harness 8 is fixed to the bracket 5 is located near the connecting portion 81 between the harness 8 and the injector 7 in the harness 8 extending along the arrangement direction A1 of the plurality of injectors 7 . can support As a result, the fuel injection system 3 according to this embodiment can further suppress the vibration of the harness 8 for driving the injector.

A holding member 82 for holding the harness 8 is attached to the bracket 5 to fix the harness 8 to the bracket 5 . Therefore, the harness 8 is more reliably fixed to the bracket 5 and fixed to the bracket 5 with a simple structure. As a result, the fuel injection system 3 according to the present embodiment can reliably fix the harness 8 to the bracket 5 by the holding member 82 while suppressing an increase in the number of parts, thereby suppressing vibration of the harness 8 .

FIG. 7 is a top view showing the arrangement relationship between the bracket and the cylinder head of this embodiment.
FIG. 8 is a top view showing the cylinder head of this embodiment.

1 and 2, the bracket 5 is secured to the top of the cylinder head 21 using the second fastening member 59. As shown in FIG. At this time, as shown in FIG. 7 , the bracket 5 is mounted on the upper portion of the cylinder head 21 straddling over the combustion chamber 215 provided in the cylinder head 21 . In the example shown in FIG. 7 , the second fixing portion 52 and the third reinforcing portion 543 of the bracket 5 straddle over the combustion chamber 215 provided in the cylinder head 21 . However, the portion of bracket 5 that straddles combustion chamber 215 is not limited to second fixing portion 52 and third reinforcing portion 543 .

As shown in FIG. 8, the cylinder head 21 has a mounting surface 216. As shown in FIG. The bracket 5 is mounted on the mounting surface 216 of the cylinder head 21 and fixed to the cylinder head 21 . As shown in FIG. 8 , the mounting surface 216 is provided in a region straddling over the combustion chamber 215 provided in the cylinder head 21 . For example, the combustion chamber 215 shown in FIGS. 7 and 8 is an auxiliary chamber (that is, an auxiliary combustion chamber) formed inside the cylinder head 21 .

Here, the injector 7 is mounted on the upper portion of the cylinder head 21 as described above with reference to FIGS. Also, the fuel pressure accumulator 6 and the fuel pipe 61 are provided at a position spaced upward from the cylinder head 21 . Therefore, if bracket 5 is not present, a relatively large amount of space exists above and above cylinder head 21 . As a result, combustion noise generated in the combustion chamber 215 may easily leak above the cylinder head 21 .

On the other hand, according to the fuel injection system 3 according to the present embodiment, the bracket 5 supporting the fuel pressure accumulator 6 is mounted on the upper portion of the cylinder head 21 across the upper side of the combustion chamber 215 of the engine 2. and is fixed to the upper portion of the cylinder head 21 . As described above, the bracket 5 is mounted and fixed on the upper part of the cylinder head 21 while straddling the upper side of the combustion chamber 215 of the engine 2, so that the combustion noise generated in the combustion chamber 215 of the engine 2 is reduced to the cylinder head. Leakage above 21 can be suppressed. Also, the bracket 5 that supports the fuel pressure accumulator 6 functions as a heavy object fixed to the upper portion of the cylinder head 21 and exerts a damping effect at the portion fixed to the cylinder head 21 . Therefore, the bracket 5 has a function of blocking combustion noise generated in the combustion chamber 215 of the engine 2, that is, a sound insulation function. Thereby, the fuel injection system 3 according to this embodiment can reduce combustion noise generated in the combustion chamber 215 of the engine 2 .

In addition, when the combustion chamber 215 is a pre-chamber formed inside the cylinder head 21, the bracket 5 prevents the combustion noise generated in the pre-chamber from leaking above the cylinder head 21 directly above the pre-chamber. be able to. Also, the bracket 5 that supports the fuel pressure accumulator 6 functions as a heavy object fixed to the upper portion of the cylinder head 21 and exerts a damping effect at the portion fixed to the cylinder head 21 . Therefore, the bracket 5 has a function of blocking combustion noise generated in the pre-chamber, that is, a sound insulation function. As a result, when the combustion chamber 215 is a pre-chamber formed inside the cylinder head 21, the fuel injection system 3 according to the present embodiment efficiently reduces the combustion noise generated in the pre-chamber of the pre-chamber engine. can be reduced.

Further, the cylinder head 21 has a mounting surface 216 on which the bracket 5 is mounted. Therefore, the fuel injection system 3 according to the present embodiment prevents the bracket 5 from being distorted when the bracket 5 is assembled and fixed to the cylinder head 21, and stabilizes the bracket 5 with respect to the upper part of the cylinder head 21. can be permanently fixed. In addition, the fuel injection system 3 according to this embodiment can improve the ease of assembly of the bracket 5 to the upper portion of the cylinder head 21 . Furthermore, when the combustion chamber 215 is a pre-chamber formed inside the cylinder head 21, the mounting surface 216 of the cylinder head 21 extends above the pre-chamber provided in the cylinder head 21 of the pre-chamber engine. It is provided in the crossing area. Therefore, the bracket 5 is stably mounted on the mounting surface 216 provided in the region straddling over the upper part of the pre-chamber while straddling the upper part of the pre-chamber, and is stably fixed to the upper part of the cylinder head 21. . As a result, the bracket 5 can suppress transmission of vibrations caused by combustion in the pre-chamber upward to the cylinder head 21 . As a result, when the combustion chamber 215 is a pre-chamber formed inside the cylinder head 21, the fuel injection system 3 according to the present embodiment reduces combustion noise generated in the pre-chamber and vibration caused by combustion in the pre-chamber. can be reduced.

FIG. 9 is a perspective view of the fuel pressure accumulator of the present embodiment when viewed obliquely from below.
For convenience of explanation, FIG. 9 omits the convex portion 64 press-fitted and fixed in the hole 63 .

3 and 4, the projection 64 (not shown in FIG. 9) is press-fitted into the hole 63 of the fuel pressure accumulator 6 and fixed. A fastening surface 631 is provided around the hole 63 . The fastening surface 631 is a surface that contacts the fastening surface 512 (see FIG. 4) of the bracket 5 when the fuel pressure accumulator 6 is fastened to the bracket 5 using the first fastening member 62 .

The injector 7 (not shown in FIG. 9) is inserted into the insertion hole 66 of the fuel pressure accumulator 6 and directly connected to the fuel pressure accumulator 6 . The end of the injector 7 is liquid-tightly inserted and held in the insertion hole 66 by an O-ring attached to the injector 7, for example. As a result, the injector 7 injects the fuel supplied through the insertion hole 66 of the fuel pressure accumulator 6 into the combustion chamber 215 . A positioning surface 661 is provided around the insertion hole 66 . The positioning surface 661 is a surface that contacts the biasing member 72 attached to the injector 7 and determines the position of the injector 7 .

As shown in FIG. 9 , the fastening surface 631 formed around the hole 63 is flush with the positioning surface 661 formed around the insertion hole 66 . As a result, the fuel injection system 3 according to the present embodiment can be easily assembled and improved in workability. It can be stably fixed.

The embodiments of the present invention have been described above. However, the present invention is not limited to the above embodiments, and various modifications can be made without departing from the scope of the claims. Some of the configurations of the above embodiments may be omitted, or may be arbitrarily combined in a manner different from the above.

2: Engine 3: Fuel Injection System 5: Bracket 6: Fuel Accumulator 7: Injector 8: Harness 21: Cylinder Head 22: Head Cover 23: Intake Manifold 51: First Fixing Part 52 : Second fixing part 53: Third fixing part 59: Second fastening member 61: Fuel pipe 62: First fastening member 63: Hole 64: Convex part 66: Insertion hole 71: Positioning surface , 72: biasing member, 81: connecting portion, 82: holding member, 211: sleeve, 212: insertion hole, 213: female screw, 214: positioning surface, 215: combustion chamber, 216: mounting surface, 511: female Screw 512: Fastening surface 513: Recess 521: Hole 531: Hole 541: First reinforcing part 542: Second reinforcing part 543: Third reinforcing part 631: Fastening surface 641: Tip part 661: Positioning surface 821: Projection A1: Arrangement direction D1, D2: Distance

Claims (10)

A fuel injection system for injecting fuel into a combustion chamber of an engine,
a bracket fixed to the cylinder head of the engine;
a fuel pressure accumulator supported and fixed to the bracket for accumulating the fuel supplied from the fuel pump;
an injector directly connected to the fuel pressure accumulator and mounted on the cylinder head for injecting the fuel supplied from the fuel pressure accumulator into the combustion chamber;
with
The fuel pressure accumulator is fixed to the bracket using a first fastening member,
The bracket is fixed to the cylinder head using a second fastening member, and has a first fixing portion that engages with the first fastening member and a second fixing portion that has a hole through which the second fastening member passes, which are adjacent to each other. formed in a ladder-like or grid-like shape and having a reinforcing portion that connects and reinforces the first fixing portion and the second fixing portion ;
The injector is mounted on the cylinder head by being inserted into an insertion hole formed in the cylinder head through a gap in the bracket formed in the ladder shape or the lattice shape. injection system. The reinforcing portion is a first reinforcing portion,
The bracket further includes a second reinforcing portion that connects and reinforces the first fixing portions that are adjacent to each other, and a third reinforcing portion that connects and reinforces the second fixing portions that are adjacent to each other. The fuel injection system according to claim 1, wherein: the first fastening member is engaged with the first fixing portion from above through a hole formed in the fuel pressure accumulator;
3. The fuel injection system according to claim 1, wherein the second fastening member engages with the cylinder head from above through the hole formed in the second fixing portion. A fastening surface of the fuel pressure accumulator that contacts and is fastened to the bracket is flush with a positioning surface of the fuel pressure accumulator that contacts the injector and determines the position of the injector. 4. The fuel injection system according to any one of 1 to 3. The fuel injection system according to any one of claims 1 to 4, wherein at least one of the fuel pressure accumulator and the bracket has a guide member that guides the injector to a mounting position on the cylinder head. . The guide member is
a convex portion provided on one of the fuel pressure accumulator and the bracket;
a concave portion provided in the other of the fuel pressure accumulator and the bracket and into which the convex portion is fitted;
6. The fuel injection system of claim 5, comprising: 7. The fuel injection system according to claim 6, wherein a direction in which the projection fits into the recess is parallel to a direction in which the injector is inserted into the insertion hole. 8. The fuel injection system according to claim 7, wherein the cylinder head has a sleeve that is press-fitted into the insertion hole and determines an insertion position of the injector with respect to the insertion hole. The fuel injection system according to any one of claims 6 to 8, wherein the guide member has a plurality of projections and a plurality of recesses in which the plurality of projections are respectively fitted. system. 10. The method according to any one of claims 6 to 9, wherein when the injector is mounted on the cylinder head, the projection begins to fit into the recess before the position of the injector with respect to the cylinder head is determined. The fuel injection system according to .

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