JP2022104099A - Diesel engine and its manufacturing method - Google Patents

Abstract

To provide a diesel engine for actualizing precise fuel injection, and its manufacturing method.SOLUTION: A fuel injector 7 includes a large-diameter body part 7c, a small-diameter nozzle part 7d, and a thrust surface 7e formed on a step area between the body part 7c and the nozzle part 7d, the nozzle part 7d of the fuel injector 7 being inserted through from the inside of a sleeve 10 to the inside of an insertion hole 1a so that the fuel injector 7 is thrust to a swirl chamber 2 side with thrust force 11 and the thrust force 11 on the fuel injector 7 is received from the thrust surface 7e of the fuel injector 7 via a washer 12 by a pressure receiving surface 10b of the sleeve 10. An elastic ring gasket 22 which is pressed against an outer peripheral face 10kb of a gasket fitting boss 10k with the elastic restoration of a snap ring 21 and the elastic ring gasket 22 is held between the washer 12 and a gasket installation surface 10h with the thrust force 11 on the fuel injector 7.SELECTED DRAWING: Figure 1

Description

The present invention relates to a diesel engine, and more particularly to a diesel engine capable of performing precise fuel injection and a method for manufacturing the same.

Conventionally, as a diesel engine, there is an engine provided with a vortex chamber type combustion chamber, an insertion hole in a cylinder head facing the vortex chamber, and a fuel injector inserted through the insertion hole (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2020-67065 (see FIG. 1)

<< Problem >> It may not be possible to perform precise fuel injection.
In the engine of Patent Document 1, when the main body of the fuel injector is arranged in the cylinder head, the main body of the fuel injector may be overheated by the heat of the cylinder head, and precise fuel injection may not be possible.

An object of the present invention is to provide a diesel engine capable of performing precise fuel injection and a method for manufacturing the same.

(Invention according to claim 1)
The structure of the invention according to claim 1 is as follows.
As illustrated in FIG. 1 (A), the cylinder (3), the cylinder head (1), the vortex chamber (2) in the cylinder head (1), and the main combustion chamber (4) in the cylinder (3). , A communication port (5) for communicating the main combustion chamber (4) and the vortex chamber (2), an insertion hole (1a) in the cylinder head (1) facing the vortex chamber (2), and an insertion hole (1a). In a diesel engine equipped with a fuel injector (7) inserted into
As illustrated in FIG. 1A, a sleeve (10) protruding from the insertion hole (1a) to the outside of the cylinder head (1) and a pressure receiving surface (10a) provided on the protruding end portion (10a) of the sleeve (10). With 10b)
The fuel injector (7) has a pressing surface (7e) formed on a step portion of a main body portion (7c) having a large diameter, a nozzle portion (7d) having a small diameter, and a main body portion (7c) and a nozzle portion (7d). Equipped with
The nozzle portion (7d) of the fuel injector (7) is inserted from the sleeve (10) through the insertion hole (1a), and the fuel injector (7) is pressed toward the vortex chamber (2) by the pressing force (11). The pressing force (11) applied to the fuel injector (7) is received by the pressing surface (10b) of the sleeve (10) from the pressing surface (7e) of the fuel injector (7) via the seat (12). Being done
As illustrated in FIG. 1A, the sleeve (10) has a gasket mounting surface (10h) and a gasket fitting boss (10k) protruding from the gasket mounting surface (10h) toward the seat (12). The protruding end surface (10ka) of the gasket fitting boss (10k) is the pressure receiving surface (10b) of the sleeve (10), and the elastic ring gasket (22) externally fitted to the gasket fitting boss (10k). A snap ring (21) fitted to the elastic ring gasket (22) is provided, and the elastic restoring force of the snap ring (21) and the elastic ring gasket (22) is applied to the outer peripheral surface (10 kb) of the gasket fitting boss (10 k). The pressure-welded elastic ring gasket (22) is sandwiched between the seat (12) and the gasket installation surface (10h) by the pressing force (11) applied to the fuel injector (7). diesel engine.
(Invention according to claim 6)
The structure of the invention according to claim 6 is as follows.
The method for manufacturing a diesel engine according to claim 4.
As illustrated in FIG. 4A, the elastic ring gasket (22) and the snap ring (21) are externally fitted in the middle of the outer peripheral surface (10 g) of the sleeve (10) before being attached to the cylinder head (1). A step of temporarily fixing a gasket or the like that is temporarily fixed by its elastic restoring force, a sleeve attaching step of attaching the sleeve (10) to the cylinder head (1) as illustrated in FIG. 4 (B), and FIG. 4 (C). The injector insertion step of inserting the fuel injector (7) into the sleeve (10) and the elastic ring gasket (22) temporarily fixed to the sleeve (10) as illustrated in FIG. 4 (D). Is pushed by the snap ring (21), and the elastic ring gasket (22) is slid along the outer peripheral surface (10 g) of the sleeve (10) to move the gasket to the outer peripheral side of the gasket fitting boss (10 k). As illustrated in FIG. 4E, the elastic ring gasket (22) is fitted with a gasket fitting boss (22) by the elastic restoring force of the elastic ring gasket (22) and the snap ring (21) that shrink inward in the radial direction. The seat (12) is a step of mounting a gasket or the like to be mounted on the outer peripheral surface (10 kb) of 10 k) in a pressure-welded state, and a pressing force (11) applied to the fuel injector (7) as illustrated in FIG. 4 (F). It is characterized by having a sealing process in which an elastic ring gasket (22) is sandwiched between the gasket mounting surface (10h) and the seat metal (12) and the gasket mounting surface (10h) are sealed. How to make a diesel engine.

The invention according to claim 1 has the following effects.
<< Effect 1 >> Precise fuel injection can be performed.
As illustrated in FIG. 1A, in this engine, the sleeve (10) keeps the main body portion (7c) of the fuel injector (7) away from the cylinder head (1), so that the heat of the cylinder head (1) is increased. The main body (7c) of the fuel injector (7) is less likely to overheat, and precise fuel injection can be performed.
<< Effect 2 >> The sealability between the washer (12) and the gasket installation surface (10h) is high.
As illustrated in FIG. 1A, the elastic ring gasket (22) is pressed against the outer peripheral surface (10 kb) of the gasket fitting boss (10 k) by the elastic restoring force of the snap ring (21) and the elastic ring gasket (22). ) Is sandwiched between the washer (12) and the gasket installation surface (10h) by the pressing force (11) applied to the fuel injector (7), so that the washer (12) and the gasket installation surface (10h) Highly sealed between.

The invention according to claim 6 has the following effects in addition to the effects 1 and 2 of the invention according to claim 1.
<< Effect 3 >> It is possible to prevent the engine manufacturing work from being interrupted due to the elastic ring gasket (22) falling off.
During the assembly process of the fuel injectors (7) exemplified in FIGS. 4 (A) to 4 (F), the elastic ring gasket (22) does not fall off, so that the engine manufacturing work is interrupted due to the fall off of the elastic ring gasket (22). Can be prevented.

It is a figure regarding the basic example of the engine part used for the diesel engine which concerns on embodiment of this invention, FIG. 1A is a vertical sectional view of a vortex chamber and its peripheral part, FIG. FIG. 1 (C) is an enlarged view of a direction arrow, FIG. 1 (C) is an enlarged view of a direction of arrow C in FIG. 1 (A), and FIG. 1 (D) is an enlarged view of an enlarged view of a direction D in FIG. 1 (A). In the figure regarding the sleeve used for the engine of FIG. 1, FIG. 2A shows a basic example, and FIG. 2B shows a modified example 1. 3A and 3B are explanatory views regarding the assembly of the fuel injector of the engine of FIG. 1, FIG. 3A is an assembly structure of the fuel injector, FIG. 3B is a plan view of an elastic ring gasket used for assembly, and FIG. 3B is a plan view. Is a plan view of the snap ring used for assembly. 4A and 4B are views for explaining the assembly process of the fuel injector in the engine manufacturing method of FIG. 1, FIG. 4A is a temporary fixing process for an elastic ring gasket and the like, and FIG. 4B is a sleeve mounting process. 4 (C) is the process of inserting the fuel injector, FIG. 4 (D) is the process of moving the elastic ring gasket or the like, FIG. 4 (E) is the process of mounting the elastic ring gasket or the like, and FIG. 4 (F) is the washer (12). Seal between the gasket installation surface (10h). The sealing process of is shown.

5 (A) is a basic example, FIG. 5 (B) is a modified example 2-1 and FIG. 5 (C) is a modified example 2-2. , FIG. 5 (D) shows the modified example 2-3. 6 (A) shows a modified example 3 and FIG. 6 (B) shows a modified example 4 in a diagram relating to a sealing structure on the inner peripheral side of the sleeve used in the engine of FIG. In the figure regarding the sealing structure on the inner peripheral side of the sleeve used in the engine of FIG. 1, FIG. 7A shows the modified example 5-1 and FIG. 7B shows the modified example 5-2. 8 (A) is a basic example, FIG. 8 (B) is a modified example 6-1 and FIG. 8 (C) is a modified example 6-2, which is a diagram relating to a sealing structure of the outer circumference of the sleeve used in the engine of FIG. 8 (D) shows the modification 6-3. 9 (A) shows a basic example, and FIG. 9 (B) shows a modified example 7 in a diagram relating to a waterproof and dustproof structure around a washer used in the engine of FIG. 10 (A) shows a basic example, and FIG. 10 (B) shows a modified example 8 in a diagram relating to a basic example of each part of the engine used in the engine of FIG. 1 and a combination example of a modified example.

11A is a sectional view taken along line XIA-XIA of FIG. 1B, and FIG. 11B is FIG. 1B, which is a diagram illustrating a basic example of a fuel injection hole of the fuel injector used in the engine of FIG. ) Corresponding diagram, FIG. 11 (C) is a corresponding diagram of FIG. 1 (C). FIG. 12 (A) is a diagram corresponding to FIG. 11 (A), FIG. 12 (B) is a diagram corresponding to FIG. 11 (B), and FIG. (C) is a diagram corresponding to FIG. 11 (C). 11 is a diagram corresponding to FIG. 11A relating to a first comparative example of a fuel injection hole of a fuel injector. FIG. 11 (A) is a diagram corresponding to FIG. 11 (A) regarding a second comparative example of a fuel injection hole of a fuel injector. FIG. 15 (A) is a diagram corresponding to FIG. 11 (A), FIG. 15 (B) is a diagram corresponding to FIG. 11 (B), and FIG. 15 (C) is a diagram relating to a third comparative example of a fuel injection hole of a fuel injector. It is a figure corresponding to 11 (C).

1 to 12 are diagrams for explaining a diesel engine according to an embodiment of the present invention, FIG. 1 is a basic example of each engine part used in the engine of the embodiment, and FIGS. 2 to 12 are sleeves, a sealing structure, etc. used in the embodiment. It is a basic example and a modification example about.
Further, FIGS. 13 to 15 are diagrams of comparative examples regarding the fuel injection holes.

In the embodiment of the present invention shown in FIG. 1, a vertical in-line multi-cylinder electronic fuel injection diesel engine is used.
As shown in FIG. 1 (A), this engine includes a cylinder (3), a cylinder head (1) assembled on the upper part of the cylinder (3), and a piston (14) fitted in the cylinder (3). It is equipped with.

As shown in FIG. 1 (A), this engine has a vortex chamber (2) in a cylinder head (1), a main combustion chamber (4) in a cylinder (3), a main combustion chamber (4) and a vortex. An electronic fuel injection type fuel inserted into the communication port (5) for communicating the chamber (2), the insertion hole (1a) in the cylinder head (1) toward the vortex chamber (2), and the insertion hole (1a). It is equipped with an injector (7).

This engine is a 4-cycle engine. In this engine, compressed air is pushed from the main combustion chamber (4) to the vortex chamber (2) through the communication port (5) near the top dead point of the compression stroke, and the vortex chamber is used. The injected fuel (13) shown in FIG. 11 (A) is injected from the fuel injector (7) into the swirling flow (2a) of the compressed air generated in (2), and the combustion gas generated by combustion in the vortex chamber (2). Is ejected from the communication port (5) shown in FIG. 1 (A) into the main combustion chamber (4), and the unburned fuel contained in the combustion gas is mixed with the air in the main combustion chamber (4) and burned.

As shown in FIG. 1A, a piston ring (14a) is externally fitted to the piston (14), and the piston (14) has the cylinder center axis (3a) side as the front side and the cylinder peripheral wall (3b) side as the rear side. ) Is provided with a gas guide groove (14b) that gradually becomes shallower as it approaches the front side.
The vortex chamber (2) is spherical and is formed in the cylinder head (1). The reference numeral (2b) in FIG. 1 (A) is the center of the vortex chamber (2).
The communication port (5) is formed in a base (15) fitted in the cylinder head (1), and is directed from the main combustion chamber (4) diagonally upward to the vortex chamber (2). The opening (5d) on the main combustion chamber (4) side of the communication port (5) is arranged directly above the rear end portion (14c) of the gas guide groove (14b).
The main combustion chamber (4) is formed in a space sandwiched between the cylinder head (1) and the piston (14) from above and below in the cylinder (3).
A head gasket (16) is sandwiched between the cylinder (3), the cylinder head (1) and the base (15).

As shown in FIG. 1 (A), this engine is provided on a sleeve (10) protruding from the insertion hole (1a) to the outside of the cylinder head (1) and a protruding end portion (10a) of the sleeve (10). It has a pressure receiving surface (10b).
As shown in FIG. 1A, the fuel injector (7) has a step between a large diameter main body portion (7c), a small diameter nozzle portion (7d), and a main body portion (7c) and a nozzle portion (7d). It is provided with a pressing surface (7e) formed in the portion.
In this engine, the nozzle portion (7d) of the fuel injector (7) is inserted from the sleeve (10) through the insertion hole (1a), and the fuel injector (7) is pressed by the pressing force (11) to form a vortex chamber (2). ) Side, and the pressing force (11) applied to the fuel injector (7) is received by the pressing surface (10b) of the sleeve (10) from the pressing surface (7e) of the fuel injector (7) via the seat (12). It is configured to be.

As shown in FIG. 1A, in this engine, the sleeve (10) keeps the main body portion (7c) of the fuel injector (7) away from the cylinder head (1), so that the heat of the cylinder head (1) causes it to move. The main body (7c) of the fuel injector (7) is less likely to overheat, and precise fuel injection can be performed.
In this engine, the pressing force (11) applied to the fuel injector (7) is generated by the fuel injector (7) receiving the elastic restoring force of the compressed spring plate shown in FIG. 3 (A).

As shown in FIG. 1A, the sleeve (10) includes a gasket mounting surface (10h) and a gasket fitting boss (10k) projecting from the gasket mounting surface (10h) toward the seat (12). The protruding end surface (10ka) of the gasket fitting boss (10k) is the pressure receiving surface (10b) of the sleeve (10), and the elastic ring gasket (22) externally fitted to the gasket fitting boss (10k) is elastic. A snap ring (21) fitted to the ring gasket (22) is provided, and the elastic restoring force of the snap ring (21) and the elastic ring gasket (22) is pressed against the outer peripheral surface (10 kb) of the gasket fitting boss (10 k). The elastic ring gasket (22) is sandwiched between the seat (12) and the gasket installation surface (10h) by the pressing force (11) applied to the fuel injector (7).

As shown in FIG. 1 (A), the elastic ring gasket (22) is pressed against the outer peripheral surface (10 kb) of the gasket fitting boss (10 k) by the elastic restoring force of the snap ring (21) and the elastic ring gasket (22). However, because it is sandwiched between the washer (12) and the gasket installation surface (10h) by the pressing force (11) applied to the fuel injector (7), it is between the washer (12) and the gasket installation surface (10h). Highly sealed.

In some cases, the snap ring (21) is not left in the engine, which is the final product, and the elasticity of the elastic ring gasket (22) is pressed against the outer peripheral surface (10 kb) of the gasket fitting boss (10 k) by the elastic restoring force. The ring gasket (22) may be sandwiched between the washer (12) and the gasket installation surface (10h) by the pressing force (11) applied to the fuel injector (7).

As shown in FIG. 1A, a gas seal (7f) is externally fitted to the nozzle portion (7d), and the gas seal (7f) allows the inner peripheral surface of the insertion hole (1a) and the nozzle portion (7d) to be connected. The space between the outer peripheral surface and the outer peripheral surface is sealed so that the combustion gas generated in the vortex chamber (2) does not leak to the outside through the insertion hole (1a).

The fuel injector (7) is an electronic fuel injection type.
The electronic fuel injection type fuel injector (7) is electronically controlled by the engine ECU, and a predetermined amount of injection fuel (13) is injected at a predetermined timing.
ECU is an abbreviation for electronic control unit.
In this engine, the electronic components in the main body (7c) of the fuel injector (7) are less likely to overheat, and precise electronic fuel injection control can be performed.

As shown in FIG. 1A, in this engine, the valve body (7da) is housed in the nozzle portion (7d) of the fuel injector (7), and the valve body is contained in the main body portion (7c) of the fuel injector (7). The electronic component of the valve operating device (7ca) of (7da) is housed.
Therefore, in this engine, the electronic parts of the valve drive (7ca) in the main body (7c) are less likely to be overheated by the heat of the cylinder head (1), and precise electronic fuel injection control can be performed.
Electronic components of the valve drive (7ca) include an electromagnetic coil of an electronic solenoid, a piezo element, and the like.

As shown in FIG. 1 (A), this engine includes an engine cooling air passage (1b), and in the engine cooling air passage (1b), an outer peripheral surface (7cb) of a main body portion (7c) of a fuel injector (7). ) And the outer peripheral surface (10 g) of the sleeve (10) are exposed.
In this engine, the heat of the main body (7c) and the sleeve (10) of the fuel injector (7) is radiated to the cooling air passing through the engine cooling air passage (1b), and the heat of the cylinder head (1) is used to dissipate the heat of the fuel injector (1). The main body (7c) of 7) is unlikely to overheat, and precise electronic fuel injection control can be performed.
The engine cooling air generated by the engine cooling fan (not shown) passes through the engine cooling air passage (1b) during engine operation.

In the engine of FIG. 1 (A), the basic example of the sleeve (10) shown in FIG. 2 (A) is used, and the sleeve (10) of this basic example is composed of a separate part from the cylinder head (1). It is attached to the cylinder head (1).
Therefore, in this engine, heat transfer from the cylinder head (1) to the sleeve (10) is obstructed at the attachment point of the sleeve (10), and the heat of the cylinder head (1) causes the main body of the fuel injector (7). The electronic parts in (7c) are less likely to be overheated, and precise electronic fuel injection control can be performed.
Further, when the sleeve (10) of this basic example is used, the sleeve (10) of the modification 1 shown in FIG. 2 (B) described later, that is, the sleeve (10) integrated with the cylinder head (1) is used. Compared with this, the shape of the cylinder head (1) is simplified, and the cylinder head (1) can be easily manufactured.

In the engine of FIG. 1A, the cylinder head (1) has a fitting hole (1c) provided in the outer opening of the insertion hole (1a), and the fitting hole (1c) has a base end of a sleeve (10). The portion (10c) is internally fitted.
The base end portion (10c) of the sleeve (10) is fixed to the fitting hole (1c) by press fitting.
The base end portion (10c) of the sleeve (10) may be fixed to the fitting hole (1c) by any means of press-fitting, bonding, welding, press-fitting and bonding, or press-fitting and welding. Adhesive is used for adhesion.
In this engine, cast iron can be used as the material of the cylinder head (1), and steel can be used as the material of the sleeve (10). The cylinder head (1) may be die-cast aluminum, and aluminum or other metal may be used as the material of the sleeve (10). A heat resistant resin may be used for the sleeve (10). The material of the cylinder head (1) and the material of the sleeve (10) may be the same or different.

As in the modified example 1 shown in FIG. 2B, the sleeve (10) may be an integrally molded product with the cylinder head (1).
When the sleeve (10) of the modified example 1 shown in FIG. 2 (B) is used, the sleeve (10) of the basic example shown in FIG. 2 (A), that is, the sleeve (10) of a separate part from the cylinder head (1). There is an advantage that the number of parts can be reduced as compared with the case of using.
Other configurations and functions of the modification 2 of FIG. 2B are the same as those of the basic example of FIG. 2A unless there is a particular contradiction. In FIG. 2B, the same elements as those in FIG. 2A are designated by the same reference numerals as those in FIG. 2A.

Next, the assembly structure of the fuel injector (7) of this engine will be described.
As shown in FIG. 3A, the engine comprises a bracket (29) erected on the cylinder head (1) and a delivery pipe (30) attached to the bracket (29). The base end portion of the fuel injector (7) is connected to (30), and the leaf spring (31) is sandwiched between the delivery pipe (30) and the fuel injector (7), and the elastic restoring force of the leaf spring (31). A pressing force (11) is applied to the fuel injector (7).

As shown in FIGS. 3B and 3C, the elastic ring gasket (22) is an O-ring (22a), and the snap ring (21) is a C-shaped retaining ring (21a).

Next, a method of assembling the fuel injector (7) to the cylinder head (1), which constitutes a part of the manufacturing method of this engine, will be described.
This assembly method is performed according to the order of FIGS. 4A to 4F.
As shown in FIG. 4A, this assembly method includes an elastic ring gasket (22) and a snap ring (21) in the middle of the outer peripheral surface (10 g) of the sleeve (10) before being attached to the cylinder head (1). A step of temporarily fixing a gasket or the like that is externally fitted and temporarily fixed by its elastic restoring force, a process of attaching a sleeve to attach a sleeve (10) to a cylinder head (1) as shown in FIG. 4 (B), and FIG. 4 As shown in (C), an injector insertion step of inserting the fuel injector (7) into the sleeve (10), and as shown in FIG. 4 (D), an elastic ring gasket (22) temporarily fixed to the sleeve (10). ) With the snap ring (21) and slide the elastic ring gasket (22) along the outer peripheral surface (10 g) of the sleeve (10) to move the gasket or the like to the outer peripheral side of the gasket fitting boss (10 k). As shown in the process and FIG. 4 (E), the elastic ring gasket (22) is fitted with a gasket fitting boss (22) by the elastic restoring force of the elastic ring gasket (22) and the snap ring (21) that shrink inward in the radial direction. As shown in FIG. 4 (F), the pressing force (11) applied to the fuel injector (7) is used to attach the gasket or the like to the outer peripheral surface (10 kb) of the 10 k) in a pressure-welded state. A sealing step is provided in which an elastic ring gasket (22) is sandwiched between the gasket mounting surfaces (10h) to seal between the seat (12) and the gasket mounting surface (10h).

During the assembly process of the fuel injectors (7) exemplified in FIGS. 4 (A) to 4 (F), the elastic ring gasket (22) does not fall off, so that the engine manufacturing work is interrupted due to the fall off of the elastic ring gasket (22). Can be prevented.

In order not to leave the snap ring (21) in the engine which is the final product, the snap ring is between the mounting process of the gasket or the like shown in FIG. 4 (E) and the sealing process shown in FIG. 4 (F). Remove (21).

The inner peripheral side of the engine sleeve (10) of FIG. 1 (A) has no gasket and no sealing function as in the basic example of FIG. 5 (A), but the inner peripheral side of the sleeve (10) has a sealing function. 5 (B) to (D), as shown in the modified examples 2-1 to 2-3, 3 shown in FIGS. A sealing structure by a ring gasket (24) fitted in the provided ring groove (23) may be used.
The ring gasket (24) is an O-ring (24a) in the modified example 2-1 shown in FIG. 5 (B), and an X-ring (24b) having an X-shaped cross section in the modified example 2-2 shown in FIG. 5 (C). ), A triangular ring (24c) having a triangular cross section is used in the modified example 2-3 shown in FIG. 5 (D), and a seal lip ring (24d) is used in the modified example 3 shown in FIG. 6 (A). .. The seal lip ring (24d) is provided with a seal lip (24da) on the inner circumference.
The seal lip ring (24d) is press-fitted into the ring groove (23). The ring gasket (24) is pressure-welded to the outer peripheral surface (7de) of the nozzle portion (7d) of the fuel injector (7).

When the ring gaskets (22) of the modified examples 2-1 to 2-3,3 are used, the elastic restoring force of the ring gasket (22), which is difficult to shift in the ring groove (21), causes the inside of the sleeve (10). The sealing between the peripheral surface (10d) and the outer peripheral surface (7de) of the nozzle portion (7d) of the fuel injector (7) can be reliably performed.

The sealing structure on the inner peripheral side of the sleeve (10) is a ring gasket (24) fixed by baking to the inner peripheral surface (10d) of the sleeve (10) as in the modified example 4 shown in FIG. 6 (B). It may be the one used.
In the modified example 4 shown in FIG. 6B, a triangular ring (24c) having a triangular cross section is used.
A plurality of the triangular rings (24c) are arranged in the axial length direction of the inner peripheral surface (10d) of the sleeve (10).
The triangular ring (24c) is in pressure contact with the outer peripheral surface (7de) of the nozzle portion (7d) of the fuel injector (7).

When the ring gasket (24) of this modification 4 is used, the inner peripheral surface (10d) of the sleeve (10) and the nozzle portion of the fuel injector (7) are provided by the elastic restoring force of the ring gasket (22) that does not shift in position due to baking. It is possible to reliably perform sealing with the outer peripheral surface (7de) of (7d).

The sealing structure on the inner peripheral side of the sleeve (10) has the inner peripheral surface (10d) of the sleeve (10) and the nozzle portion (7) of the fuel injector (7) as shown in the modified example 5-61 shown in FIG. 7 (A). An embedded seal (25) embedded between the outer peripheral surface (7de) of 7d) may be used.
The embedded seal (25) is in close contact with the inner peripheral surface (10d) of the sleeve (10) and the outer peripheral surface (7de) of the nozzle portion (7d) of the fuel injector (7).
A resin such as rubber or acrylic can be used as the material of the embedded seal (25).

When the embedded seal (25) of this modification 5-1 is used, the inner peripheral surface (10d) of the sleeve (10) and the nozzle portion (7d) of the fuel injector (7) are used in the embedded seal (25) that does not shift in position due to embedding. ) Can be reliably sealed with the outer peripheral surface (7de).

The sealing structure on the inner peripheral side of the sleeve (10) has the inner peripheral surface (10d) of the sleeve (10) and the nozzle portion (7) of the fuel injector (7) as shown in the modified example 5-72 shown in FIG. 7 (B). A filling sealant (26) filled between the outer peripheral surface (7de) of 7d) may be used.
The filling sealant (26) fills the gap between the inner peripheral surface (10d) of the sleeve (10) and the outer peripheral surface (7de) of the nozzle portion (7d) of the fuel injector (7).
Grease or resin can be used as the material of the filling sealant (26).
The peripheral wall of the sleeve (10) is provided with an injection hole (10e) for injecting the filling sealant (26).
The injection hole (10e) is closed with a plug (10f) after injecting the filling sealant (26).

When the filling sealant (26) of this modification 5-2 is used, the inner peripheral surface (10d) of the sleeve (10) and the nozzle portion (7d) of the fuel injector (7) are filled with the filling sealant (26). The seal between the outer peripheral surface (7 de) and the outer peripheral surface (7 de) can be reliably performed.

The outer peripheral side of the sleeve (10) of FIG. 1A has no sealing means and has no sealing function as in the basic example of FIG. 8A, but has a sealing function on the outer peripheral side of the sleeve (10). As shown in the modified examples 6-1 to 6-3 shown in FIGS. 8 (B) to 6-3, the outer peripheral surface (10 g) of the sleeve (10) and the outer peripheral surface (12b) of the washer (12) are covered. A sealed structure with a band (27) wound in the circumferential direction may be used.
In the modified example 6-1 shown in FIG. 8 (B), the rubber band (27a) is attached to the band material (27), and in the modified example 6-2 shown in FIG. 8 (C), the rubber seal (27b) is attached to the band material (27). ), In the modified example 6-3 shown in FIG. 8 (D), the adhesive tape (27c) is used for the band material (27), respectively.

By using the strips (27) of the modified examples 6-1 to 6-3, the gap between the outer peripheral surface (10 g) of the sleeve (10) and the outer peripheral surface (12b) of the washer (12) is surely sealed. , The seal between the pressing surface (12a) of the washer (12) and the pressure receiving surface (10b) of the sleeve (10) can be strengthened.

In the engine of FIG. 1A, the outer peripheral side of the washer (12) has no waterproof / dustproof means and no waterproof / dustproof function as in the basic example of FIG. 9A, but the outer peripheral side of the washer (12). In order to provide the waterproof and dustproof function to the engine, a waterproof and dustproof structure may be used in which the washer (12) is covered with a cover (28) from the outer circumference as shown in the modified example 7 shown in FIG. 9B.
In the modified example 7 shown in FIG. 9B, the mounting cover (28b) attached to the fuel injector (7) is used as the cover (28).
The mounting cover (28b) is locked to the main body portion (7c) of the fuel injector (7).

When the mounting cover (28b) of the modification 7 shown in FIG. 9B is used, the outer peripheral surface (7ccb) of the main body portion (7c) of the fuel injector (7) and the outer peripheral surface (12b) of the washer (12) can be used. The boundary, the boundary between the outer peripheral surface (12b) of the washer (12) and the pressure receiving surface (10b) of the sleeve (10) is covered from the outer periphery by the mounting cover (28b), and moisture and dust into the sleeve (10) are collected. Entry is prevented.

The basic examples and modified examples shown in FIGS. 2 to 9 can be freely combined with each other.
FIG. 10A is a basic example relating to a combination of the basic examples shown in FIGS. 2 to 9. FIG. 10B is a modification 8 relating to a combination of the rubber band (27a) of the modification 6-1 of FIG. 8B and the mounting cover (28b) of the modification 7 of FIG. 9B. In the modified example 8, the sealing structure on the inner peripheral side of the sleeve of FIGS. 5 (B) to (D), FIGS. 6 (A) (B), and 7 (A) (B), and the washer of FIG. 9 (C) are shown. A waterproof and dustproof structure on the outer peripheral side may be combined.

Next, the tip arrangement of the fuel injector (7) will be described.
As shown in FIG. 1 (B), the fuel injector (7) is provided with a fuel injection hole (9) on the tip surface (7db) of the nozzle portion (7d) facing the vortex chamber (2).
As shown in FIG. 1 (A), in this engine, a part of the tip surface (7db) of the nozzle portion (7d) protrudes into the vortex chamber (2).
In this engine, the entire tip surface (7db) of the nozzle portion (7d) may protrude into the vortex chamber (2).

In this engine, as shown in FIG. 1 (A), a part or all of the tip surface (7db) of the nozzle portion (7d) of the fuel injector (7) protrudes into the vortex chamber (2). The combustion flame near the outlet of the fuel injection hole (9) shown in 11 (A) and 12 (A) is easily blown off by the swirling flow (2a) shown in FIG. 1 (A), and the heat of the combustion flame causes the fuel injector ( The electronic parts of the valve drive (7ca) in the main body (7c) of 7) are less likely to be overheated, and precise electronic fuel injection control can be performed.

Next, the fuel injection hole (9) of the fuel injector (7) will be described.
FIG. 11 relates to a basic example of the fuel injection hole (9), and FIG. 12 relates to a modified example 9.
As shown in FIGS. 11 (A) and 12 (A), the fuel injection hole (9) has a tapered shape with a bulging tip.

In this engine, as shown in FIGS. 11 (A) and 11 (A), the fuel injection hole (9) has a tapered shape, so that even if soot is accumulated at the outlet of the fuel injection hole (9), Fuel injection is not easily disturbed, and precise fuel injection control can be performed regardless of the accumulation of soot at the outlet of the fuel injection hole (9) of the fuel injector (7).

Further, in this engine, as shown in FIG. 1A, a part or all of the tip surface (7db) of the nozzle portion (7d) of the fuel injector (7) protrudes into the vortex chamber (2). , The combustion gas near the outlet of the fuel injection hole (9) shown in FIGS. 11 (A) and 12 (A) is easily blown off by the swirling flow (2a) shown in FIG. 1 (A), and the soot in the combustion gas is generated. It is difficult to grow at the outlet of the fuel injection hole (9).

As shown in FIGS. 1A and 1B, a flat vortex guide surface (7dc) around the fuel injection hole (9) is provided on the tip surface (7db) of the nozzle portion (7d) of the fuel injector (7). It is equipped with.
As shown in FIG. 1 (A), the entire vortex flow guide surface (7 dc) protrudes into the vortex chamber (2).
In this engine, a part of the vortex flow guide surface (7dc) may protrude into the vortex chamber (2).

As shown in FIG. 1A, in this engine, since at least a part of the vortex flow guide surface (7dc) protrudes into the vortex chamber (2), the swirling flow (2) swirls in the vortex chamber (2). 2a) is guided by the vortex guide surface (7dc), the swirling flow (2a) swirls smoothly in the vortex chamber (2), the mixture of the compressed air and the injected fuel (13) becomes good, and the vortex chamber (2) ) Is less likely to generate soot.
The fuel injection hole (9) is formed on a spheroidal cutting edge surface (7dd) in the center of the tip surface (7db) of the nozzle portion (7d).

As shown in FIGS. 1B, 11B, and 12B, this engine is provided with a plurality of fuel injection holes (9) for each fuel injector (7).
Therefore, the injection fuel (13) shown in 11 (B) and 12 (B) is widely dispersed in the vortex chamber (2), and the mixture of the compressed air and the injection fuel (13) becomes good, and the vortex chamber (2) ) Is less likely to generate soot.

As shown in FIGS. 1B, 11B, and 12B, six fuel injection holes (9) are provided for each fuel injector (7).
In this engine, it is desirable to provide 2 to 6 fuel injection holes (9) for each fuel injector (7).

In the basic example of the fuel injection hole (9) shown in FIGS. 1B, 11A, and 11B, the inlet opening (9a) 6 of the fuel injection hole (9) of one fuel injector (7) The total opening area of each piece is A square mm, the exhaust volume for one cylinder is C cubic mm, and the value of A / C obtained by dividing the former value A by the latter value C is 0.75 × ^10-6 . I did it. Specifically, the total opening area A of the six inlet openings (9a) of the fuel injection hole (9) was set to 0.224 mm2, and the displacement C for one cylinder was set to 299000 cubic mm. The same applies to the modified example 9 of the fuel injection hole (9) shown in FIG.
In this engine, it is desirable that the A / C value is 0.5 × 10 ^-6 to 1.0 × 10 ^-6 .

If the A / C value is less than 0.5 × ^10-6 , the total opening area A of the inlet opening (9a) of the fuel injection hole (9) may be insufficient and the required output may not be obtained. .. When the value of A / C exceeds 1.0 × ^10-6 , the total opening area A of the inlet opening (9a) of the fuel injection hole (9) becomes excessive, the fuel injection speed is slow, and the vortex chamber ( The oil droplets of the injected fuel (13) do not become fine in 2), the mixture of the compressed air and the injected fuel becomes poor, and soot is likely to be generated in the vortex chamber (2).
On the other hand, when the A / C value is 0.5 × 10 ^-6 to 1.0 × 10 ^-6 , the required output can be obtained and soot is less likely to be generated in the vortex chamber (2). ..

In the basic example of the fuel injection hole (9) shown in FIG. 11A, the total opening area of the six outlet openings (9b) of the fuel injection hole (9) of one fuel injector (7) is B square mm. 1. The total opening area of 6 inlet openings (9a) of the fuel injection holes (9) of one fuel injector (7) is A square mm, and the former value B is divided by the latter value A. The value is set to 1.26 (Note) reference. Specifically, as described above, the total opening area A of the six inlet openings (9a) of the fuel injection hole (9) is 0.224 mm2, and the six outlet openings (9b) of the fuel injection hole (9) are six. The total opening area B of the above was 0.282 mm2. In the modified example 9 of the fuel injection hole (9) shown in FIG. 12 (A), the value of B / A is slightly larger than 1.26.
In this engine, it is desirable that the B / A value is 1.08 to 1.44.

When the value of B / A is less than 1.08, the total opening area B of the outlet opening (9b) is too small with respect to the total opening area A of the inlet opening (9a) of the fuel injection hole (9), and the fuel A small amount of soot deposited at the outlet of the injection hole (9) may interfere with fuel injection and reduce the accuracy of fuel injection control.
When the B / A value exceeds 1.44, the total opening area B of the outlet opening (9b) is too large for the total opening area A of the inlet opening (9a) of the fuel injection hole (9), and the fuel The growth rate of soot deposits is high at the outlet of the injection hole (9), and a large amount of soot deposits may interfere with fuel injection, resulting in a decrease in the accuracy of fuel injection control.
On the other hand, when the B / A value is 1.08 to 1.44, the fuel injection is not hindered by a small amount of soot deposits, and the soot deposits at the outlet of the fuel injection hole (9). The growth rate of the object is slow, and the accuracy of fuel injection control does not easily decrease.

The reason why the growth rate of soot deposits increases at the exit of the fuel injection hole (9) when the B / A value exceeds 1.44, whereas the growth rate slows down at 1.44 or less. , Is estimated as follows. That is, in the former, the gap (9h) formed around the injected fuel (13) at the outlet of the fuel injection hole (9) becomes excessive, and a large amount of combustion gas containing soot flows into this gap (9h). While the soot deposit grows rapidly, in the latter, the gap (9h) formed around the injected fuel (1) at the outlet of the fuel injection hole (9) becomes an appropriate size, and the soot deposits. It is presumed that the growth rate of the object and the removal rate of the soot deposit by the injection fuel (13) antagonize each other, and the soot deposit grown at the outlet of the fuel injection hole (9) is immediately removed by the injection fuel. ..

As shown in FIG. 2C, in this engine, a plurality of vortex chamber side extension lines (7b) of the injector central axis (7a) pass through the communication port (5) and as shown in FIG. 11B. The (6) fuel injection holes (9) are arranged around the injector center axis (7a), and as shown in FIG. 11 (C), the plurality (6) fuel injection holes (9) of the plurality (6) fuel injection holes (9). The total number (6) of the vortex chamber side extension lines (9d) of the injection hole central axis (9c) passes through the communication port (5).
In this engine, only a part of the total number (6) of the extension lines (9d) on the vortex chamber side may pass through the communication port (5).
In this engine, a large amount of injection fuel (13) is injected into the main combustion chamber (4) through the communication port (5), so that excessive combustion in the vortex chamber (2) is prevented and the vortex chamber (2) is prevented. ) Is less likely to generate soot.
A plurality (6) fuel injection holes (9) are arranged around the central axis (7a) of the injector at regular intervals in the circumferential direction of the tip protruding surface (8a) of the injector tip surface (8). Has been done.

In the fuel injection hole (9) of the modification 9 shown in FIG. 12, as shown in FIG. 12 (C), the vortex chamber side extension line (7b) of the injector central axis (7a) passes through the communication port (5). , As shown in FIG. 12B, a plurality (6) fuel injection holes (9) of each fuel injector (7) are arranged around the central axis (7a) of each injector, and are arranged around the central axis (7a) of each injector. As shown in), a part (5) of the vortex chamber side extension lines (9d) of the injection hole center axis (9c) of the plurality (6) fuel injection holes (9) of each fuel injector (7). ) Abuts on the peripheral edge (5b) of the vortex chamber side opening (5a) of the communication port (5). The remaining number (1) penetrates the communication port (5).
In this engine, the entire number (6) may abut on the peripheral edge (5b) of the vortex chamber side opening (5a) of the communication port (5).
In this engine, a large amount of injection fuel (13) is injected into the main combustion chamber (4) through the communication port (5), so that excessive combustion in the vortex chamber (2) is prevented and the vortex chamber (2) is prevented. ) Is less likely to generate soot.

As shown in FIG. 12C, in the fuel injection hole (9) of the modified example 9, when viewed in a direction parallel to the vortex chamber side extension line (7b) of the injector central axis (7a), before and after being orthogonal to each other. Assuming a vortex chamber side opening (5a) with each dimension in the direction and the lateral direction enlarged by 1.5 times and a similar imaginary line (5c) with a similar shape, this similar imaginary line (5c) and the vortex chamber The peripheral surface of the vortex chamber side between the side opening (5a) and the peripheral surface of the vortex chamber side opening (5a) to which the vortex chamber side extension line (9d) of the injection hole center axis (9c) of the fuel injection hole (9) abuts. It is said to be (5b).
In the modified example 9 of the fuel injection hole (9) shown in FIG. 12, the same elements as the basic example of the fuel injection hole (9) shown in FIG. 11 are designated by the same reference numerals as those in FIG. Unless otherwise specified, the elements of the modified example of the fuel injection hole (9) shown in FIG. 12 have the same structure and function as the elements of the basic example of the fuel injection hole (9) shown in FIG.

When the state of soot generation in the vortex chamber (2) was investigated, the total number of the vortex chamber side extension lines (9d) of the injection hole center axis (9c) of the plurality (6) fuel injection holes (9) ( FIG. 12 shows a basic example of FIG. 11 in which 6) pass through the communication port (5), and FIG. In the modified example 9, the vortex chamber (2) has a total number (6) as compared with the third comparative example of FIG. The amount of soot generated was small.
In the third comparative example shown in FIG. 15, the same elements as the basic example shown in FIG. 11 and the modified example shown in FIG. 12 are designated by adding 100 to the reference numerals of FIGS. 11 and 12. The same applies to the first comparative example shown in FIG. 13 and the second comparative example shown in FIG.

As shown in FIG. 11A, in the basic example of the fuel injection hole (9), the expansion of each injection hole center axis (9c) (or its vortex chamber side extension line (9d)) with respect to the injector center axis (7a). The opening angle (α) is 4 °.
As shown in FIG. 12A, in the modified example 9 of the fuel injection hole (9), the injection hole center axis (9c) (or its vortex chamber side extension line (9d)) with respect to the injector center axis (7a). The expansion angle (α) is 7 °.
In this engine, it is desirable that the expansion angle (α) of each injection hole center axis (9c) (or its vortex chamber side extension line (9d)) with respect to the injector center axis (7a) is 4 ° to 7 °. ..

When the expansion angle (α) is less than 4 °, some of the plurality of injected fuels (13) are likely to overlap each other, and soot is likely to be generated in the vortex chamber (2).
When the expansion angle (α) exceeds 7 °, most of the injected fuel (13) collides with the inner surface of the vortex chamber (2) without passing through the communication port (5), and enters the vortex chamber (2). Soot is likely to be generated due to excessive combustion in.
On the other hand, when the expansion angle (α) is 4 ° to 7 °, soot is unlikely to be generated in the vortex chamber (2).

When the state of soot generation in the vortex chamber (2) was investigated, in the basic example (FIG. 11) in which the expansion angle (α) was 4 ° and the modified example 9 (FIG. 12) in which the expansion angle (α) was 7 °, the soot was 0 °. Compared with 1 comparative example (FIG. 13), 1 ° second comparative example (FIG. 14), and 10 ° third comparative example (FIG. 15), soot was generated less in the vortex chamber (2).

In the fuel injection hole (9) of the basic example shown in FIG. 11A, the taper angle (β) of each fuel injection hole (9) is set to 12 °.
In the modified example 9 of the fuel injection hole (9) shown in FIG. 12A, the taper angle (β) of each fuel injection hole (9) is set to 18 °.
In this engine, the taper angle (β) is preferably 12 ° to 18 °.

When the taper angle (β) is less than 12 °, the outlet opening (9b) is too small for the inlet opening (9a) of the fuel injection hole (9), and a small amount deposited at the outlet of the fuel injection hole (9). The soot may interfere with fuel injection and reduce the accuracy of fuel injection control.
When the taper angle (β) exceeds 18 °, the outlet opening (9b) is too large for the inlet opening (9a) of the fuel injection hole (9), and soot is deposited at the outlet of the fuel injection hole (9). The growth rate of objects is high, and a large amount of soot deposits interfere with fuel injection, which may reduce the accuracy of fuel injection control.
On the other hand, when the taper angle (β) is 12 ° to 18 °, a small amount of soot deposits do not interfere with fuel injection, and soot deposits grow at the outlet of the fuel injection hole (9). The speed is slow and the accuracy of fuel injection control does not easily decrease.

When the growth rate of soot deposits at the outlet of the fuel injection hole (9) was investigated, in the basic example (FIG. 11) with a taper angle (β) of 12 ° and the modified example 9 (FIG. 12) with a taper angle (β) of 18 °, Compared to the 0 ° first comparative example (FIG. 13), the 6 ° second comparative example (FIG. 14), and the 24 ° third comparative example (FIG. 15), the soot at the outlet of the fuel injection hole (9) The growth rate of the sediment was slow.

As in the third comparative example of FIG. 15, when the taper angle (β) exceeds 18 °, the growth rate of soot deposits increases at the outlet of the fuel injection hole (109), whereas the growth rate of soot deposits increases in FIG. When the taper angle (β) is 18 ° or less as in the basic example and the modified example 9 in FIG. 12, the reason why the growth rate slows down is presumed as follows. That is, in the former, a relatively large gap (109h) is formed around the injected fuel (113) at the outlet of the fuel injection hole (109), and a large amount of combustion gas containing soot flows into this large gap (109h). While the soot deposit grows rapidly, in the latter, the gap (9h) around the injected fuel (13) becomes an appropriate size at the outlet of the fuel injection hole (9), and the soot deposit grows. It is presumed that the speed and the removal rate of the soot deposit by the injection fuel (13) antagonize each other, and the soot deposit grown at the outlet of the fuel injection hole (9) is immediately removed by the injection fuel.

As shown in FIG. 11A, in the basic example of the fuel injection hole (9), the angle between the injector center axis (7a) and the inner peripheral surface (9g) of each injection hole along the injector center axis (7a). (γ) is 1 °.
As shown in FIG. 12A, in the modified example 9 of the fuel injection hole (9), the injector central axis (7a) is sandwiched between the inner peripheral surface (9g) of each injection hole along the injector center axis (7a). The angle (γ) is set to 3 °.
In this engine, the narrowing angle (γ) is preferably 1 ° to 3 °.

When the sandwiching angle (γ) is less than 1 °, some of the plurality of injected fuels (13) are likely to overlap each other, and soot is likely to be generated in the vortex chamber (2). When the expansion angle (α) exceeds 3 °, most of the injected fuel (13) collides with the inner surface of the vortex chamber (2) without passing through the communication port (5), and enters the vortex chamber (2). Soot is likely to be generated due to excessive combustion in.
On the other hand, when the sandwiching angle (γ) is 1 ° to 3 °, soot is unlikely to be generated in the vortex chamber (2).

When the state of soot generation in the vortex chamber (2) was investigated, in the basic example (FIG. 11) in which the sandwiching angle (γ) was 1 ° and the modified example 9 (FIG. 12) in which the sandwiching angle (γ) was 3 °, the first one was 0 °. The amount of soot generated in the vortex chamber (2) was smaller than that of the comparative example (FIG. 13) and the comparative example of 4 ° (not shown).

As shown in FIG. 11A, in the basic example of the fuel injection hole (9), the inlet opening edge (9e) of the fuel injection hole (9) has a sharp pin angle (9f) that is not chamfered. ing.
Also in the modification 9 of the fuel injection hole (9) shown in FIG. 12A, the inlet opening edge (9e) of the fuel injection hole (9) has a sharp pin angle (9f) that is not chamfered. ..

In this engine, the inlet opening edge (9e) of the fuel injection hole (9) is left with a sharp pin angle (9f) that is not chamfered, so that chamfering is not required, and the fuel injector (7) is manufactured. Will be easier.
Further, in this engine, since the fuel injector (7) injects fuel into the vortex chamber (2), the fuel injection pressure can be lower than that of the direct injection type, and the pin angle (9f) due to the fuel injection pressure can be increased. Wear is unlikely to occur, and the resulting deterioration in fuel injection accuracy is unlikely to occur.

The pin angle (9f) is a sharp opening edge having an R of 0.1 mm or less.

(1) ... Cylinder head, (1a) ... Insertion hole, (1b) ... Engine cooling air passage, (2) ... Vortex chamber, (3) ... Cylinder, (4) ... Main combustion chamber, (5) ... Communication port , (6) ... Insertion hole, (7) ... Fuel injector, (7c) ... Main body, (7ca) ... Valve drive, (7cc) ... Outer surface, (7d) ... Nozzle, (7da) ... Valve Body, (7db) ... tip surface, (7dc) ... vortex guide surface, (10) ... sleeve, (10a) ... protruding end, (10b) ... pressure receiving surface, (10h) ... gasket installation surface, (10k) ... Gasket fitting boss, (10ka) ... protruding end surface, (10kb) ... outer peripheral surface, (11) ... pressing force, (12) ... washer, (12a) ... pressing surface, (21) ... snap ring, (21a) ... C-shaped retaining ring, (22) ... elastic ring gasket, (22a) ... O-ring.

Claims (6)

Cylinder (3), cylinder head (1), vortex chamber (2) in cylinder head (1), main combustion chamber (4) in cylinder (3), main combustion chamber (4) and vortex chamber It is provided with a communication port (5) for communicating (2), an insertion hole (1a) in the cylinder head (1) toward the vortex chamber (2), and a fuel injector (7) inserted through the insertion hole (1a). In the diesel engine
A sleeve (10) protruding from the insertion hole (1a) to the outside of the cylinder head (1) and a pressure receiving surface (10b) provided at the protruding end portion (10a) of the sleeve (10) are provided.
The fuel injector (7) has a pressing surface (7e) formed on a step portion of a main body portion (7c) having a large diameter, a nozzle portion (7d) having a small diameter, and a main body portion (7c) and a nozzle portion (7d). Equipped with
The nozzle portion (7d) of the fuel injector (7) is inserted from the sleeve (10) through the insertion hole (1a), and the fuel injector (7) is pressed toward the vortex chamber (2) by the pressing force (11). The pressing force (11) applied to the fuel injector (7) is received by the pressing surface (10b) of the sleeve (10) from the pressing surface (7e) of the fuel injector (7) via the seat (12). Being done
The sleeve (10) includes a gasket mounting surface (10h) and a gasket fitting boss (10k) protruding from the gasket mounting surface (10h) toward the seat (12), and the gasket fitting boss (10k) protrudes. The end surface (10ka) was used as the pressure receiving surface (10b) of the sleeve (10), and was externally fitted to the elastic ring gasket (22) fitted to the gasket fitting boss (10k) and the elastic ring gasket (22). The elastic ring gasket (22) provided with the snap ring (21) is pressed against the outer peripheral surface (10 kb) of the gasket fitting boss (10 k) by the elastic restoring force of the snap ring (21) and the elastic ring gasket (22). A diesel engine characterized in that it is sandwiched between a seat (12) and a gasket installation surface (10h) by a pressing force (11) applied to a fuel injector (7). In the diesel engine according to claim 1,
A diesel engine characterized in that the elastic ring gasket (22) is an O-ring (22a) and the snap ring (21) is a C-shaped retaining ring (21a). In the electronic fuel injection diesel engine according to claim 1 or 2.
The engine cooling air passage (1b) is provided, and the outer peripheral surface (7cc) of the main body portion (7c) of the fuel injector (7) and the outer peripheral surface (10g) of the sleeve (10) are exposed in the engine cooling air passage (1b). It is an electronic fuel injection type diesel engine characterized by being. In the electronic fuel injection type diesel engine according to any one of claims 1 to 3.
The sleeve (10) is an electronic fuel injection type diesel engine characterized in that it is composed of a separate part from the cylinder head (1) and is attached to the cylinder head (1). In the electronic fuel injection type diesel engine according to any one of claims 1 to 4.
A fuel injection hole (9) is provided on the tip surface (7db) of the nozzle portion (7d) facing the vortex chamber (2).
An electronic fuel injection diesel engine characterized in that a part or all of the tip surface (7db) of the nozzle portion (7d) protrudes into the vortex chamber (2). The method for manufacturing a diesel engine according to claim 4.
A gasket or the like in which an elastic ring gasket (22) and a snap ring (21) are externally fitted in the middle of the outer peripheral surface (10 g) of the sleeve (10) before being attached to the cylinder head (1) and temporarily fixed by the elastic restoring force. Temporary fixing step, sleeve attaching step to attach the sleeve (10) to the cylinder head (1), injector insertion step to insert the fuel injector (7) into the sleeve (10), and temporary fixing to the sleeve (10). Push the elastic ring gasket (22) with the snap ring (21) and move the elastic ring gasket (22) to the outer peripheral side of the gasket fitting boss (10k) while sliding it along the outer peripheral surface (10 g) of the sleeve (10). The outer peripheral surface of the gasket fitting boss (10k) is fitted with the elastic ring gasket (22) by the moving process of the gasket etc. to be moved and the elastic restoring force of the elastic ring gasket (22) and the snap ring (21) that shrink inward in the radial direction. An elastic ring gasket (22) is placed between the seat (12) and the gasket installation surface (10h) in the process of mounting a gasket or the like to be mounted on (10 kb) in a pressure-welded state and the pressing force (11) applied to the fuel injector (7). A method for manufacturing a diesel engine, which comprises a sealing step of sandwiching and sealing between a seat (12) and a gasket mounting surface (10h).

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