Electronic fuel injection diesel engine

Abstract

An electronic fuel injection diesel engine that performs precise electronic fuel injection control is provided. A fuel injector (7) is configured to have a large-diameter main body portion (7c), a small-diameter nozzle portion (7d), and a pressing surface (7e) formed at a step portion of the main body portion (7c) and the nozzle portion (7d). The nozzle portion (7d) of the fuel injector (7) is inserted through a sleeve (10) and into a through-hole (1a). The fuel injector (7) is pressed by a pressing force (11) toward a swirl chamber (2). The pressing force (11) applied to the fuel injector (7) is received by a pressure receiving surface (10b) of the sleeve (10) via a gasket (12) from the pressing surface (7e) of the fuel injector (7).

Description

Technical Field

[0001] This invention relates to an electronic fuel injection diesel engine, and more specifically, to an electronic fuel injection diesel engine capable of precise electronic fuel injection control. Background Technology

[0002] Conventionally, as an electronic fuel injection diesel engine, there is a diesel engine that has a swirl chamber combustion chamber, a through hole in the cylinder head facing the swirl chamber, and an electronic fuel injection fuel injector inserted into the through hole (for example, see Patent Document 1).

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2020-67065 (see reference) Figure 1 ) Summary of the Invention

[0006] The problem that the invention aims to solve

[0007] Problem: Inability to perform precise electronic fuel injection control.

[0008] In the engine of Patent Document 1, when the main body of the fuel injector is located inside the cylinder head, the electronic components inside the main body of the fuel injector overheat due to the heat of the cylinder head, making it impossible to perform precise electronic fuel injection control.

[0009] The objective of this invention is to provide an electronic fuel injection diesel engine capable of precise electronic fuel injection control.

[0010] Technical means to solve the problem

[0011] The main structure of the invention described in this application is as follows.

[0012] like Figure 1 As illustrated in (A), an electronic fuel injection diesel engine includes a cylinder (3), a cylinder head (1), a swirl chamber (2) within the cylinder head (1), a main combustion chamber (4) within the cylinder (3), a communication port (5) connecting the main combustion chamber (4) and the swirl chamber (2), a through hole (1a) within the cylinder head (1) facing the swirl chamber (2), and an electronic fuel injection fuel injector (7) inserted into the through hole (1a), characterized in that,

[0013] like Figure 1As illustrated in (A), the electronic fuel injection diesel engine includes a sleeve (10) protruding from the through hole (1a) outward from the cylinder head (1) and a pressure-receiving surface (10b) provided at the protruding end (10a) of the sleeve (10).

[0014] The fuel injector (7) has a large-diameter main body (7c), a small-diameter nozzle (7d), and a pressing surface (7e) formed by the stepped portions of the main body (7c) and the nozzle (7d).

[0015] The nozzle portion (7d) of the fuel injector (7) is inserted through the sleeve (10) into the insertion hole (1a). The fuel injector (7) is pressed towards 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 (7e) of the fuel injector (7) via the washer (12) and the pressure-receiving surface (10b) of the sleeve (10).

[0016] Invention Effects

[0017] The invention described in this application has the following effects.

[0018] Effect: Enables precise electronic fuel injection control.

[0019] like Figure 1 As illustrated in (A), in this engine, the main body (7c) of the fuel injector (7) is moved away from the cylinder head (1) by the sleeve (10). Therefore, the electronic components in the main body (7c) of the fuel injector (7) are not easily overheated by the heat of the cylinder head (1), and precise electronic fuel injection control can be performed. Attached Figure Description

[0020] Figure 1 This is a diagram showing basic examples of the engine components used in a diesel engine according to an embodiment of the present invention. Figure 1 (A) is a longitudinal sectional view of the vortex chamber and its surrounding parts. Figure 1 (B) is Figure 1 Enlarged view of (A) in direction B. Figure 1 (C) is Figure 1 (A) is a magnified view of the C direction. Figure 1 (D) is Figure 1 (A) is a magnified view of the D direction.

[0021] Figure 2 It is about Figure 1 A diagram of the sleeve used in the engine. Figure 2 (A) shows the basic example. Figure 2 (B) shows a variation of example 1.

[0022] Figure 3 It's about in Figure 1 A diagram showing the sealing structure of the pressure-bearing surface of the sleeve used in an engine. Figure 3 (A) shows the basic example. Figure 3 (B) shows a variation 2-1. Figure 3 (C) shows a variation 2-2. Figure 3 (D) shows variations 2-3.

[0023] Figure 4 It is about Figure 1 A diagram showing the structure of the pressure-bearing surface of the sleeve used in the engine. Figure 4 (A) shows the basic example. Figure 4 (B) shows a variation 3-1. Figure 4 (C) shows variation 3-2.

[0024] Figure 5 It is about Figure 1 A diagram showing the sealing structure of the pressure-bearing surface of the sleeve used in an engine. Figure 5 (A) shows a variation 4-1. Figure 5 (B) shows a variation 4-2. Figure 5 (C) shows variation 4-3. Figure 5 (D) shows variation 4-4.

[0025] Figure 6 It is about Figure 1 A diagram showing the sealing structure on the inner circumference side of the sleeve used in an engine. Figure 6 (A) shows the basic example. Figure 6 (B) shows a variation of example 5-1. Figure 6 (C) shows a variation 5-2. Figure 6 (D) shows variation 5-3, Figure 6 (E) shows variation 5-4, Figure 6 (F) shows variation 5-5.

[0026] Figure 7 It is about Figure 1 A diagram showing the sealing structure on the inner circumference side of the sleeve used in an engine. Figure 7 (A) shows variations 5-6. Figure 7 (B) shows variations 5-7.

[0027] Figure 8 It is about Figure 1 A diagram of the sealing structure on the outer periphery of the sleeve used in an engine. Figure 8 (A) shows the basic example. Figure 8 (B) shows a variation of example 6-1. Figure 8(C) shows a variation of example 6-2. Figure 8 (D) shows variation 6-3.

[0028] Figure 9 It is about Figure 1 A diagram showing the waterproof and dustproof structure around the gasket used in an engine. Figure 9 (A) shows the basic example. Figure 9 (B) shows a variation 7-1. Figure 9 (C) shows a variation 7-2.

[0029] Figure 10 It is about Figure 1 The diagram shows basic examples, modified examples, and combined examples of various engine components used in engines. Figure 10 (A) shows the basic example. Figure 10 (B) shows variation 8.

[0030] Figure 11 It is used to explain about Figure 1 A diagram showing a basic example of the fuel injection orifice of a fuel injector used in an engine. Figure 11 (A) is Figure 1 (B) Sectional view along line XIA-XIA. Figure 11 (B) is Figure 1 The equivalent diagram of (B), Figure 11 (C) is Figure 1 The equivalent diagram of (C).

[0031] Figure 12 It is about Figure 1 Figure 9 shows a modified example of the fuel injection orifice of a fuel injector used in an engine. Figure 12 (A) is Figure 11 The equivalent diagram of (A), Figure 12 (B) is Figure 11 The equivalent diagram of (B), Figure 12 (C) is Figure 11 The equivalent diagram of (C).

[0032] Figure 13 This is the first comparative example regarding the fuel injection orifice of a fuel injector. Figure 11 (A) Equivalent diagram.

[0033] Figure 14 This is a second comparative example concerning the fuel injection orifice of a fuel injector. Figure 11 (A) Equivalent diagram.

[0034] Figure 15 This is a diagram of the third comparative example of a fuel injector's fuel injection orifice. Figure 15 (A) is Figure 11The equivalent diagram of (A), Figure 15 (B) is Figure 11 (B) equivalent diagram, Figure 15 (C) is Figure 11 (C) equivalent diagram. Detailed Implementation

[0035] Figures 1-12 This is a diagram illustrating a diesel engine according to an embodiment of the present invention. Figure 1 This is a basic example of the various parts of the engine used in the implementation method. Figures 2-12 These are basic and modified examples of sleeves, sealing structures, etc. used in the implementation methods.

[0036] in addition, Figures 13-15 This is a diagram of a comparative example of a fuel injection orifice.

[0037] exist Figure 1 In the embodiment of the present invention shown, a vertical inline multi-cylinder electronic fuel injection diesel engine is used.

[0038] like Figure 1 As shown in (A), the engine includes: a cylinder (3), a cylinder head (1) assembled on the upper part of the cylinder (3), and a piston (14) embedded in the cylinder (3).

[0039] like Figure 1 As shown in (A), the engine includes: a swirl chamber (2) in the cylinder head (1), a main combustion chamber (4) in the cylinder (3), a communication port (5) that connects the main combustion chamber (4) and the swirl chamber (2), a through hole (1a) in the cylinder head (1) facing the swirl chamber (2), and an electronic fuel injection type fuel injector (7) inserted into the through hole (1a).

[0040] This engine is a four-stroke engine. In this engine, compressed air is forced from the main combustion chamber (4) into the vortex chamber (2) through the connecting port (5) near the top dead center of the compression stroke. Fuel is injected from the fuel injector (7) into the swirling flow (2a) of the compressed air generated in the vortex chamber (2). Figure 11 The fuel (13) shown in (A) is injected, and the combustion gases produced during combustion in the vortex chamber (2) are generated from... Figure 1 The connecting port (5) shown in (A) sprays into the main combustion chamber (4), and the unburned fuel contained in the combustion gas mixes with the air in the main combustion chamber (4) and burns.

[0041] The electronic fuel injection type fuel injector (7) is electronically controlled by the engine ECU to inject a specified amount of fuel (13) at a specified time.

[0042] ECU is short for Electronic Control Unit.

[0043] like Figure 1 As shown in (A), a piston ring (14a) is embedded outside the piston (14), with the cylinder central axis (3a) side as the front side and the cylinder peripheral wall (3b) side as the rear side. The upper surface of the piston (14) has a gas guide groove (14b) that gradually becomes shallower as it approaches the front side.

[0044] The vortex chamber (2) is spherical and is formed inside the cylinder head (1). Figure 1 The reference numeral (2b) in (A) is the center of the vortex chamber (2).

[0045] The connecting port (5) is formed in the interface (15) embedded in the cylinder head (1), extending obliquely upwards and backwards from the main combustion chamber (4) toward the vortex chamber (2). The opening (5d) of the connecting port (5) on the main combustion chamber (4) side is positioned directly above the rear end (14c) of the gas guide groove (14b).

[0046] The main combustion chamber (4) is formed within the cylinder (3) by the space between the cylinder head (1) and the piston (14).

[0047] A cover gasket (16) is clamped between the cylinder (3), the cylinder head (1), and the interface (15).

[0048] like Figure 1 As shown in (A), the engine has a sleeve (10) protruding from the through hole (1a) outward to the cylinder head (1) and a pressure surface (10b) provided at the protruding end (10a) of the sleeve (10).

[0049] like Figure 1 As shown in (A), the fuel injector (7) has a large-diameter main body (7c), a small-diameter nozzle (7d), and a pressing surface (7e) formed on the stepped portions of the main body (7c) and the nozzle (7d).

[0050] In this engine, the nozzle part (7d) of the fuel injector (7) is inserted through the sleeve (10) into the insertion hole (1a). The fuel injector (7) is pressed towards 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 (7e) of the fuel injector (7) via the washer (12) and the pressure surface (10b) of the sleeve (10).

[0051] like Figure 1 As shown in (A), in this engine, the main body (7c) of the fuel injector (7) is moved away from the cylinder head (1) by the sleeve (10). Therefore, the electronic components in the main body (7c) of the fuel injector (7) are not easily overheated by the heat of the cylinder head (1), and precise electronic fuel injection control can be performed.

[0052] It should be noted that in this engine, the pressing force (11) applied to the fuel injector (7) is generated by the elastic restoring force of the compressed spring plate (not shown) of the fuel injector (7).

[0053] like Figure 1 As shown in (A), a gas seal (7f) is embedded outside the nozzle part (7d). The gas seal (7f) seals the inner circumferential surface of the insertion hole (1a) and the outer circumferential surface of the nozzle part (7d) so that the combustion gas generated in the vortex chamber (2) will not leak to the outside through the insertion hole (1a).

[0054] like Figure 1 As shown in (A), in this engine, a valve body (7da) is housed in the nozzle portion (7d) of the fuel injector (7), and the electronic components of the valve drive device (7ca) of the valve body (7da) are housed in the main body portion (7c) of the fuel injector (7).

[0055] Therefore, in this engine, the electronic components of the valve drive device (7ca) in the main body (7c) are not easily overheated by the heat of the cylinder head (1), and precise electronic fuel injection control can be performed.

[0056] The electronic components of the valve drive unit (7ca) include electromagnetic coils of electronic solenoids, piezoelectric elements, etc.

[0057] like Figure 1 As shown in (A), the engine has an engine cooling air passage (1b), and the outer peripheral surface (7cb) of the main body (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).

[0058] In this engine, the heat of the main body (7c) and sleeve (10) of the fuel injector (7) is dissipated to the cooling air through the engine cooling air passage (1b). The main body (7c) of the fuel injector (7) is not easily overheated by the heat of the cylinder head (1), and precise electronic fuel injection control can be performed.

[0059] In the engine cooling air path (1b), engine cooling air generated by the engine cooling fan (not shown) passes through during engine operation.

[0060] exist Figure 1 In engine (A), using Figure 2 The basic example of the sleeve (10) shown in (A) is made of a component different from that of the cylinder head (1) and is installed on the cylinder head (1).

[0061] Therefore, in this engine, the heat transfer from the cylinder head (1) to the sleeve (10) is blocked at the mounting position of the sleeve (10), and the electronic components in the main body (7c) of the fuel injector (7) are not easily overheated by the heat of the cylinder head (1), enabling precise electronic fuel injection control.

[0062] Furthermore, if the sleeve (10) of this basic example is used, then it is similar to the one described later. Figure 2 Compared to the case where the sleeve (10) of the modified example 1 shown in (B) is an integral sleeve (10) with the cylinder head (1), the shape of the cylinder head (1) becomes simpler and the manufacturing of the cylinder head (1) becomes easier.

[0063] exist Figure 1 In the engine of (A), the cylinder head (1) has an insertion hole (1c) provided in the outer opening of the insertion hole (1a), and the base end (10c) of the sleeve (10) is embedded in the insertion hole (1c).

[0064] The base end (10c) of the sleeve (10) is fixed to the insertion hole (1c) by pressing.

[0065] The base end (10c) of the sleeve (10) can be fixed to the embedded hole (1c) by any of the following methods: pressing, bonding, welding, pressing and bonding, pressing and welding. Bonding is done using an adhesive.

[0066] In this engine, the cylinder head (1) can be made of cast iron, and the sleeve (10) can be made of steel. The cylinder head (1) can be an aluminum die casting, and the sleeve (10) can also be made of other metals such as aluminum. The sleeve (10) can also be made of heat-resistant resin. The materials of the cylinder head (1) and the sleeve (10) can be the same or different.

[0067] like Figure 2 As shown in variant example 1 (B), the sleeve (10) can also be an integrally molded part relative to the cylinder head (1).

[0068] When using Figure 2 In the case of sleeve (10) of the modified example 1 shown in (B), Figure 2 Compared to the case of the sleeve (10) of the basic example shown in (A), which is a separate component of the cylinder head (1), the sleeve (10) has the advantage of being able to reduce the number of components.

[0069] Figure 2 As long as there is no particular contradiction with the other structures and functions of variation example 2 of (B), then... Figure 2 The basic example of (A) is the same. Figure 2 In (B), regarding... Figure 2 (A) Same feature label and Figure 2 (A) has the same reference numerals.

[0070] exist Figure 1 In the engine shown in (A), the sealing structure of the pressure-bearing surface (10b) of the sleeve (10) uses Figure 3 The basic example shown in (A) is as follows.

[0071] like Figure 3 As shown in (A), in this basic example, the pressing surface (12a) of the washer (12) and the pressure-receiving surface (10b) of the sleeve (10) are sealed only by crimping based on the pressing force (11).

[0072] The sealing structure of the pressure-bearing surface (10b) of the sleeve (10) is as follows Figure 3 As shown in variant example 2-1 of (B), the pressing surface (12a) of the washer (12) and the pressure-receiving surface (10b) of the sleeve (10) can also be sealed with adhesive (17).

[0073] When using this modified example 2-1, the seal based on the press is strengthened by the adhesive (17), thus improving the sealing performance.

[0074] In this situation, water and dust are less likely to enter the sleeve (10) from between the pressing surface (12a) of the gasket (12) and the pressure-bearing surface (10b) of the sleeve (10). Water and dust entering the sleeve (10) can then enter the fuel injector (7), causing it to malfunction. In addition, water that enters the sleeve (10) before the engine's sintering coating is vaporized by the heat during sintering, causing the coating to expand from the inside and resulting in peeling.

[0075] The sealing structure of the pressure-bearing surface (10b) of the sleeve (10) is as follows Figure 3 As shown in variant example 2-2 of (C), the pressing surface (12a) of the washer (12) and the pressure-receiving surface (10b) of the sleeve (10) can also be sealed with grease (18).

[0076] According to this modified example 2-2, the seal based on crimping is reinforced by grease (18), which improves the sealing performance.

[0077] The sealing structure of the pressure-bearing surface (10b) of the sleeve (10) is as follows Figure 3 As shown in variants 2-3 of (D), the pressing surface (12a) of the gasket (12) and the pressure-bearing surface (10b) of the sleeve (10) can also be sealed by a sheet gasket (19).

[0078] When using the modified example 2-3, the seal based on the press is reinforced by the sheet gasket (19), which improves the sealing performance.

[0079] Sheet gaskets (19) can be made of materials such as metal, resin, and rubber.

[0080] exist Figure 1 In the engine of (A), the pressing surface (12a) of the washer (12) and the pressure-receiving surface (10b) of the sleeve (10) are used Figure 4 The basic example shown in (A) is as follows.

[0081] exist Figure 4 In the basic example shown in (A), the pressure surface (10b) of the sleeve (10) and the pressing surface (12a) of the washer (12) are both composed of only flat surfaces.

[0082] The pressing surface (12a) of the washer (12) and the pressure-bearing surface (10b) of the sleeve (10) are as follows: Figure 4 As shown in variations 3-1 and 3-2 of (B) and (C), concentric circular or vortex-shaped grooves (20) extending circumferentially are formed on one or both of the pressure surface (10b) of the sleeve (10) and the pressing surface (12a) of the washer (12).

[0083] exist Figure 4 In the modified example 3-1 shown in (B), concentric circular grooves (20) are formed. Figure 4 In the modified example 3-2 shown in (C), a vortex-shaped groove (20) is formed.

[0084] When using the modified example 3-1 and modified example 3-2, the pressing area of ​​the pressing surface (12a) of the gasket (12) and the pressing surface (10b) of the sleeve (10) is reduced in the groove (20), which increases the contact pressure and improves the sealing performance.

[0085] In addition, even if water or dust enters the groove (20), it is not easy for them to enter the sleeve (10) because they move circumferentially along the groove (20).

[0086] The sealing structure of the pressure-bearing surface (10b) of the sleeve (10) is as follows Figure 5 As shown in variations 4-1 to 4-3 of (A) to (C), an annular gasket (22) is used, which is embedded in an annular groove (21) provided in the pressure surface (10b) of the sleeve (10).

[0087] Ring gasket (22) in Figure 5 In variation example 4-1 shown in (A), an O-ring (22a) is used. Figure 5 In variation example 4-2 shown in (B), an X-ring (22b) with an X-shaped cross-section is used. Figure 5 In variation 4-3 shown in (C), a triangular ring (22c) with a triangular cross section is used.

[0088] When using the annular gasket (22) of variations 4-1 to 4-3, the sealing between the pressing surface (12a) of the gasket (12) and the pressure-bearing surface (10b) of the sleeve (10) can be reliably achieved by means of the elastic restoring force of the annular gasket (22) which is not prone to misalignment in the annular groove (21).

[0089] The ring gasket (22) is made of rubber.

[0090] like Figure 5 As shown in variant 4-4 of (D), the sealing structure of the pressure surface (10b) of the sleeve (10) can also use the elastic end (10ab).

[0091] In variation 4-4, the sleeve (10) has a main body (10ca) on the base end (10c) side and an elastic end (10ab) that forms part of the protruding end (10a), so that the elastic end (10ab) is tightly fitted with the main body (10ca). The elastic end (10ab) is formed of a material with an elastic coefficient smaller than that of the main body (10ca) and the washer (12) (i.e., easy to elastically deform), and the pressure surface (10b) of the sleeve (10) is formed on the elastic end (10ab).

[0092] When the elastic end (10ab) of the modified example 4-4 is used, the elastic restoring force of the elastic end (10ab) which is tightly fitted and supported on the main body (10ca) can reliably seal the pressure surface (12a) of the gasket (12) and the pressure surface (10b) of the sleeve (10).

[0093] In this case, since the elastic end (10ab) functions as a gasket, there is no need for a dedicated gasket for the pressure surface (10b) of the sealing sleeve (10).

[0094] It should be noted that, as Figure 3 (B) Figure 3 As in variations of (C) 2-1 and 2-2, the pressing surface (12a) of the washer (12) and the pressure-bearing surface (10b) of the sleeve (10) can also be sealed with adhesive (17) or grease (18).

[0095] When the main body (10ca) and the washer (12) are made of steel, the elastic end (10ab) can be made of materials such as copper, aluminum, rubber, or resin, which have a lower elastic modulus than steel.

[0096] In variation 4-4, the elastic end (10ab) and the main body (10ca) are tightly fitted together with a nested locking structure.

[0097] That is, the main body (10ca) of the sleeve (10) has an L-shaped fitting groove (10cb) on the periphery of the opening on the elastic end (10ab) side. The elastic end (10ab) has a cylindrical part (10ac) that fits tightly with the fitting groove (10cb) and a flange part (10ad) that extends radially from the cylindrical part (10ac) along the opening end face (10cc) of the main body (10ca) on the elastic end (10ab) side. The opening end face (10ae) of the flange part (10ad) is the pressure surface (10b) of the sleeve (10).

[0098] Figure 1 The inner circumferential side of the sleeve (10) of the engine (A) is as follows Figure 6 As in the basic example (A), there is no gasket and no sealing function, but in order to make the inner circumferential side of the sleeve (10) have a sealing function, it can also be like... Figure 6 As shown in variations 5-1 to 5-4 of (B) to (E), a sealing structure using an annular gasket (24) embedded in an annular groove (23) recessed in the inner circumferential surface (10d) of the sleeve (10) is used.

[0099] Ring gasket (24) in Figure 6 In variation 5-1 shown in (B), an O-ring (24a) is used. Figure 6 In the modified example 5-2 shown in (C), an X-ring (24b) with an X-shaped cross-section is used. Figure 6 In variation 5-3 shown in (D), a triangular ring (24c) with a triangular cross-section is used. Figure 6 In variation 5-4 shown in (E), a sealing lip ring (24d) is used. The sealing lip ring (24d) has a sealing lip (24da) on its inner circumference.

[0100] The sealing lip ring (24d) is pressed into the ring groove (23). The ring gasket (24) is pressed against the outer peripheral surface (7de) of the nozzle portion (7d) of the fuel injector (7).

[0101] When using the annular gasket (22) of the modified examples 5-1 to 5-4, the elastic restoring force of the annular gasket (22) which is not prone to misalignment in the annular groove (21) can reliably seal the inner circumferential surface (10d) of the sleeve (10) and the outer circumferential surface (7de) of the nozzle portion (7d) of the fuel injector (7).

[0102] The sealing structure on the inner circumference of the sleeve (10) is as follows Figure 6 As shown in variant example 5-5 of (F), an annular gasket (24) can be used, which is fixed to the inner circumferential surface (10d) of the sleeve (10) by sintering.

[0103] exist Figure 6In variation 5-5 shown in (F), a triangular ring (24c) with a triangular cross section is used.

[0104] The triangular ring (24c) has multiple rings arranged along the axial length of the inner circumferential surface (10d) of the sleeve (10).

[0105] The triangular ring (24c) is pressed against the outer peripheral surface (7de) of the nozzle portion (7d) of the fuel injector (7).

[0106] When the ring gasket (24) of the modified example 5-5 is used, under the action of the elastic restoring force of the ring gasket (22) which is misaligned due to sintering, a reliable seal can be made between the inner circumferential surface (10d) of the sleeve (10) and the outer circumferential surface (7de) of the nozzle portion (7d) of the fuel injector (7).

[0107] The sealing structure on the inner circumference of the sleeve (10) is as follows Figure 7 As shown in variations 5-6 of (A), an embedded seal (25) can also be used between the inner circumferential surface (10d) of the sleeve (10) and the outer circumferential surface (7de) of the nozzle portion (7d) of the fuel injector (7).

[0108] The embedded seal (25) is in close contact with the inner circumferential surface (10d) of the sleeve (10) and the outer circumferential surface (7de) of the nozzle portion (7d) of the fuel injector (7).

[0109] The material for embedding the seal (25) can be a resin such as rubber or acrylic.

[0110] When the embedded seal (25) of the modified example 5-6 is used, the embedded seal (25) which is not misaligned due to being embedded can reliably seal the inner circumferential surface (10d) of the sleeve (10) and the outer circumferential surface (7de) of the nozzle portion (7d) of the fuel injector (7).

[0111] The sealing structure on the inner circumference of the sleeve (10) is as follows Figure 7 As shown in (B) in variations 5-7, a filling sealant (26) can be used between the inner circumferential surface (10d) of the sleeve (10) and the outer circumferential surface (7de) of the nozzle portion (7d) of the fuel injector (7).

[0112] The filling sealant (26) fills the gap between the inner circumferential surface (10d) of the sleeve (10) and the outer circumferential surface (7de) of the nozzle portion (7d) of the fuel injector (7).

[0113] The material for the filling sealant (26) can be grease or resin.

[0114] The peripheral wall of the sleeve (10) has an injection hole (10e) for injecting a filling sealant (26).

[0115] The injection hole (10e) is plugged by the plug (10f) after the filling sealant (26) is injected.

[0116] When the filler sealant (26) of the modified examples 5-7 is used, the filler sealant (26) after being filled can reliably seal the inner circumferential surface (10d) of the sleeve (10) and the outer circumferential surface (7de) of the nozzle portion (7d) of the fuel injector (7).

[0117] Figure 1 The outer periphery of the sleeve (10) of (A) is as follows Figure 8 As with the basic example (A), there is no sealing mechanism or sealing function, but in order to give the outer periphery of the sleeve (10) a sealing function, it can also be like Figure 8 As shown in variations 6-1 to 6-3 of (B) to (D), a sealing structure using a strip (27) wound in the circumferential direction covering the outer peripheral surface (10g) of the sleeve (10) and the outer peripheral surface (12b) of the gasket (12).

[0118] exist Figure 8 In the modified example 6-1 shown in (B), the strip (27) uses a rubber strip (27a), in Figure 8 In variant example 6-2 shown in (C), the strip (27) uses a rubber seal (27b), in Figure 8 In the modified example 6-3 shown in (D), the strip (27) uses adhesive tape (27c).

[0119] When the strip (27) of the modified examples 6-1 to 6-3 is used, the gap between the outer peripheral surface (10g) of the sleeve (10) and the outer peripheral surface (12b) of the gasket (12) can be reliably sealed, and the seal between the pressing surface (12a) of the gasket (12) and the pressure-bearing surface (10b) of the sleeve (10) is strengthened.

[0120] exist Figure 1 In engine (A), the outer periphery of gasket (12) is as follows: Figure 9 As with the basic example (A), there is no waterproof and dustproof mechanism, and no waterproof and dustproof function. However, in order to make the outer periphery of the unit gasket (12) waterproof and dustproof, it is also possible to... Figure 9 As shown in variations 7-1 and 7-2 of (B) and (C), a waterproof and dustproof structure is used, in which a cover (28) covers the gasket (12) from the outer periphery.

[0121] exist Figure 9In the modified example 7-1 shown in (B), as a cover (28), a sleeve extension cover (28a) extending from the protruding end (10a) of the sleeve (10) to the protruding side is used. The sleeve extension cover (28a) covers the gasket (12) from the outer peripheral side. The main body (7c) of the fuel injector (7) is embedded in the extended end (28aa) of the sleeve extension cover (28a).

[0122] The inner circumferential surface (28ad) of the extended end (28aa) of the sleeve extension cover (28a) and the outer circumferential surface (7cb) of the main body (7c) of the fuel injector (7) are sealed by an annular gasket (28ac).

[0123] exist Figure 9 In the modified example 7-2 shown in (C), a mounting cover (28b) installed on the fuel injector (7) is used as a cover (28).

[0124] The mounting cover (28b) is locked by the main body (7c) of the fuel injector (7).

[0125] When using Figure 9 When the sleeve extension cover (28a) and mounting cover (28b) of the modified examples 7-1 and 7-2 shown in (B) and (C) are used to cover the boundary between the outer peripheral surface (7cb) of the main body part (7c) of the fuel injector (7) and the outer peripheral surface (12b) of the gasket (12), and the boundary between the outer peripheral surface (12b) of the gasket (12) and the pressure surface (10b) of the sleeve (10) from the outer periphery, moisture and dust are prevented from entering the sleeve (10).

[0126] Figures 2-9 The basic and modified examples shown can be freely combined with each other.

[0127] Figure 10 (A) is about... Figures 2-9 The basic examples shown are combined with each other to form a new basic example. Figure 10 (B) is about... Figure 5 The elastic end (10ab) of the modified example 4-4 of (D) and Figure 9 Modification 8 is a modified version of the sleeve extension cover (28a) of Modification 7-1 of (B). In Modification 8, it is also possible to... Figure 3 The sealing structure of the pressure-bearing surface of the sleeves (B) to (D) Figure 4 The pressure-bearing surfaces and other structures of the sleeves in (B) and (C) Figure 5 The sealing structure of the pressure-bearing surface of the sleeves (A) to (C) Figure 6 (B)~(F) Figure 7 The sealing structure on the inner circumference of the sleeves in (A) and (B) Figure 9The waterproof and dustproof structure on the outer periphery of the gasket (C) is combined.

[0128] Next, the front-end configuration of the fuel injector (7) will be described.

[0129] like Figure 1 As shown in (B), the fuel injector (7) has a fuel injection hole (9) on the front end face (7db) of the nozzle portion (7d) facing the vortex chamber (2).

[0130] like Figure 1 As shown in (A), in this engine, a portion of the front end face (7db) of the nozzle portion (7d) protrudes into the vortex chamber (2).

[0131] In this engine, the entire front end face (7db) of the nozzle section (7d) can also protrude into the vortex chamber (2).

[0132] In this engine, such as Figure 1 As shown in (A), part or all of the front end face (7db) of the nozzle portion (7d) of the fuel injector (7) protrudes into the vortex chamber (2), therefore, Figure 11 (A) Figure 12 The combustion flame near the outlet of the fuel injection hole (9) shown in (A) is easily affected. Figure 1 The swirling flow (2a) shown in (A) blows away the electronic components of the valve drive device (7ca) in the main body (7c) of the fuel injector (7) so that it is not easily overheated by the heat of the combustion flame and can perform precise electronic fuel injection control.

[0133] Next, the fuel injection port (9) of the fuel injector (7) will be described.

[0134] Figure 11 Regarding the basic example of fuel injection hole (9), Figure 12 Regarding variation example 9.

[0135] like Figure 11 As shown in (A) of 12 and (A) of 12, the fuel injection hole (9) is formed into a cone shape with an extended front end.

[0136] In this engine, such as Figure 11 (A) Figure 12 As shown in (A), since the fuel injection hole (9) is a cone shape with an extended front end, fuel injection is not easily hindered even if coal is piled up at the outlet of the fuel injection hole (9). Precise fuel injection control can be performed regardless of the amount of coal piled up at the outlet of the fuel injection hole (9) of the fuel injector (7).

[0137] In addition, in this engine, such as Figure 1As shown in (A), since part or all of the front end face (7db) of the nozzle portion (7d) of the fuel injector (7) protrudes into the vortex chamber (2), therefore, Figure 11 (A) Figure 12 The combustion gases near the outlet of the fuel injection hole (9) shown in (A) are easily... Figure 1 As shown in (A), the swirling flow (2a) is blown away, and the coal in the combustion gas does not easily grow at the outlet of the fuel injection hole (9).

[0138] like Figure 1 As shown in (A) and (B), on the front end face (7db) of the nozzle portion (7d) of the fuel injector (7), there is a flat vortex guide surface (7dc) around the fuel injection hole (9).

[0139] like Figure 1 As shown in (A), the entire vortex guide surface (7dc) protrudes into the vortex chamber (2).

[0140] In this engine, a portion of the vortex guide surface (7dc) may also protrude into the vortex chamber (2).

[0141] like Figure 1 As shown in (A), in this engine, since at least a part of the vortex guide surface (7dc) protrudes into the vortex chamber (2), the swirling flow (2a) circulating in the vortex chamber (2) is guided by the vortex guide surface (7dc), the swirling flow (2a) circulates smoothly in the vortex chamber (2), the mixing of compressed air and injected fuel (13) becomes good, and it is difficult to produce coal in the vortex chamber (2).

[0142] The fuel injection hole (9) is formed on the protruding spherical front end face (7dd) located at the center of the front end face (7db) of the nozzle portion (7d).

[0143] like Figure 1 (B) Figure 11 (B) Figure 12 As shown in (B), in this engine, each fuel injector (7) has multiple fuel injection holes (9).

[0144] therefore, Figure 11 (B) Figure 12 As shown in (B), the injected fuel (13) is widely dispersed in the vortex chamber (2), and the mixing of compressed air and injected fuel (13) becomes good, making it difficult to produce coal in the vortex chamber (2).

[0145] like Figure 1 (B) Figure 11 (B) Figure 12As shown in (B), there are six fuel injection holes (9) for each fuel injector (7).

[0146] In this engine, fuel injection holes (9) are preferably provided in 2 to 6 for one fuel injector (7).

[0147] exist Figure 1 (B) Figure 11 (A) Figure 11 In the basic example of the fuel injection orifice (9) shown in (B), the total opening area of ​​the six inlet openings (9a) of the fuel injection orifice (9) of a fuel injector (7) is set as A square mm, and the exhaust volume of 1 cylinder is set as C cubic mm. The value of A / C obtained by dividing the former value A by the latter value C is 0.75 × 10 -6 Specifically, the total opening area A of the six inlet openings (9a) of the fuel injection port (9) is set to 0.224 square mm, and the displacement C of one cylinder is set to 299,000 cubic mm. Figure 12 The same applies to the modified example 9 of the fuel injection hole (9) shown.

[0148] In this engine, the A / C value is preferably 0.5 × 10⁻⁶. -6 ~1.0×10 -6 .

[0149] When the value of A / C is less than 0.5 × 10 -6 In this case, the total opening area A of the inlet opening (9a) of the fuel injection orifice (9) is insufficient, and the necessary output cannot be obtained. When the value of A / C is greater than 1.0 × 10 -6 In this case, the total opening area A of the inlet opening (9a) of the fuel injection hole (9) becomes too large, the fuel injection speed slows down, the oil droplets of the fuel (13) injected in the vortex chamber (2) are not refined, the mixing of compressed air and injected fuel becomes poor, and coal is easily generated in the vortex chamber (2).

[0150] In contrast, the value of A / C is 0.5 × 10 -6 ~1.0×10 -6 Under these conditions, the required output is obtained, and coal is not easily generated in the vortex chamber (2).

[0151] exist Figure 11In the basic example of the fuel injection orifice (9) shown in (A), the total opening area of ​​the six outlet openings (9b) of the fuel injection orifice (9) of a fuel injector (7) is set to B square mm, and the total opening area of ​​the six inlet openings (9a) of the fuel injection orifice (9) of a fuel injector (7) is set to A square mm. The value of B is divided by the value of A to obtain the value of B / A, which is 1.26. Specifically, the total opening area A of the six inlet openings (9a) of the fuel injection orifice (9) is set to 0.224 square mm as described above, and the total opening area B of the six outlet openings (9b) of the fuel injection orifice (9) is set to 0.282 square mm. Figure 12 In the modified example 9 of the fuel injection hole (9) shown in (A), the value of B / A is slightly larger than 1.26.

[0152] In this engine, the B / A value is preferably 1.08 to 1.44.

[0153] When the B / A value is less than 1.08, the total opening area B of the outlet opening (9b) is too small relative to the total opening area A of the inlet opening (9a) of the fuel injection hole (9). Fuel injection is hindered by a small amount of coal accumulated at the outlet of the fuel injection hole (9), and the accuracy of fuel injection control may be reduced.

[0154] When the value of B / A is greater than 1.44, the total opening area B of the outlet opening (9b) is too large relative to the total opening area A of the inlet opening (9a) of the fuel injection hole (9). The growth rate of coal deposits at the outlet of the fuel injection hole (9) increases, and fuel injection is hindered by a large amount of coal deposits. The accuracy of fuel injection control may be reduced.

[0155] In contrast, when the B / A value is 1.08 to 1.44, the growth rate of coal deposits at the outlet of the fuel injection hole (9) slows down, and the accuracy of fuel injection control is difficult to reduce, provided that fuel injection is not hindered by a small amount of coal deposits.

[0156] When the B / A value is greater than 1.44, the growth rate of coal deposits at the outlet of the fuel injection hole (9) is faster, while below 1.44, the growth rate is slower. The reason for this is presumably as follows: In the former case, the gap (9h) formed around the injected fuel (13) at the outlet of the fuel injection hole (9) becomes too large, and a large amount of combustion gas containing coal flows into this gap (9h), causing the coal deposits to grow rapidly. In contrast, in the latter case, the gap (9h) formed around the injected fuel (13) at the outlet of the fuel injection hole (9) becomes an appropriate size, and the growth rate of the coal deposits and the removal rate of the coal deposits caused by the injected fuel (13) are inversely related. It is presumed that the coal deposits growing at the outlet of the fuel injection hole (9) are immediately removed by the injected fuel.

[0157] like Figure 12 As shown in (C), in this engine, the vortex chamber side extension (7b) of the injector central axis (7a) passes through the connecting port (5), as... Figure 11 As shown in (B), multiple (six) fuel injection holes (9) are arranged around the central axis (7a) of the injector, as... Figure 11 As shown in (C), the total number of (six) extension lines (9d) of the vortex chamber side of the central axis (9c) of the injection holes (9) of the multiple (six) fuel injection holes (9) passes through the connecting port (5).

[0158] In this engine, only a portion of the total number (six) of the vortex chamber side extension lines (9d) can pass through the connecting port (5).

[0159] In this engine, since a large amount of fuel (13) is injected into the main combustion chamber (4) through the connecting port (5), excessive combustion in the vortex chamber (2) can be prevented, and coal is not easily generated in the vortex chamber (2).

[0160] Multiple (six) fuel injection holes (9) are arranged at regular intervals around the central axis (7a) of the injector and on the foremost protruding surface (8a) of the front end face (8) of the injector.

[0161] exist Figure 12 In the fuel injection hole (9) of the modified example 9 shown, as Figure 12 As shown in (C), the extension line (7b) of the vortex chamber side of the ejector's central axis (7a) passes through the connecting port (5), as... Figure 12 As shown in (B), the multiple (six) fuel injection holes (9) of each fuel injector (7) are arranged around the central axis (7a) of each injector, as shown in (B). Figure 12As shown in (C), a portion (five) of the extension lines (9d) on the vortex chamber side of the central axis (9c) of the injection holes (9) of each fuel injector (7) abut against the periphery (5b) of the vortex chamber side opening (5a) of the connecting port (5). The remaining portion (one) passes through the connecting port (5).

[0162] In this engine, the total number of tubes (six) can also contact the periphery (5b) of the vortex chamber side opening (5a) of the connecting port (5).

[0163] In this engine, since a large amount of fuel (13) is injected into the main combustion chamber (4) through the connecting port (5), excessive combustion in the vortex chamber (2) can be prevented, and coal is not easily generated in the vortex chamber (2).

[0164] like Figure 12 As shown in (C), in the fuel injection hole (9) of modified example 9, assuming that when viewed from a direction parallel to the vortex chamber side extension line (7b) of the injector central axis (7a), each of the mutually orthogonal front-back direction and lateral dimension is magnified by 1.5 times, a similar shape imaginary line (5c) similar to the vortex chamber side opening (5a) is obtained. The inner peripheral surface of the vortex chamber between this similar shape imaginary line (5c) and the vortex chamber side opening (5a) is the periphery (5b) of the vortex chamber side opening (5a) that is contacted by the vortex chamber side extension line (9d) of the injection hole central axis (9c) of the fuel injection hole (9).

[0165] In such Figure 12 In the modified example 9 of the fuel injection orifice (9) shown, for the fuel injection orifice (9) Figure 11 The fuel injection hole (9) shown is labeled with the same basic element as the example shown. Figure 11 Same reference numerals as shown in the attached figures. Figure 12 Unless otherwise specified, the modified example of the fuel injection orifice (9) shown has the same features as... Figure 11 The fuel injection hole (9) shown is a basic example with the same structure and function.

[0166] The coal generation status in the vortex chamber (2) was investigated. The total number of lines (six) extending from the central axis (9c) of the injection holes (9) on the vortex chamber side (9d) through the connecting port (5) was [not specified]. Figure 11 In the basic example, a portion of the five roots are in contact with the periphery (5b) of the vortex chamber side opening (5a) of the connecting port (5). Figure 12 In variation example 9, compared to the total number of roots (six) contacting the outer side of the periphery (105b) of the vortex chamber side opening (105a), Figure 15 In the third comparative example of (C), the amount of coal produced in the vortex chamber (2) was small.

[0167] exist Figure 15 In the third comparative example shown, for the comparison with Figure 11 The basic example shown Figure 12 The variant examples shown are the same feature annotation pairs Figure 11 , 12 The figure label is added after 100. For Figure 13 The first comparative example shown Figure 14 The second comparative example shown is also labeled in the same way.

[0168] like Figure 11 As shown in (A), in the basic example of the fuel injection hole (9), the opening angle (α) of the central axis (9c) of each injection hole (or its vortex chamber side extension (9d)) relative to the central axis (7a) of the injector is set to 4°.

[0169] like Figure 12 As shown in (A), in the modified example 9 of the fuel injection orifice (9), the opening angle (α) of the central axis (9c) of each injection orifice (or its vortex chamber side extension line (9d)) relative to the central axis (7a) of the injector is set to 7°.

[0170] In this engine, the opening angle (α) of the central axis (9c) of each injection hole (or its vortex chamber side extension (9d)) relative to the central axis (7a) of the injector is preferably set to 4° to 7°.

[0171] When the opening angle (α) is less than 4°, a portion of the multiple injected fuels (13) can easily overlap each other, and coal becomes easier to generate in the vortex chamber (2).

[0172] When the opening angle (α) is greater than 7°, a large amount of injected fuel (13) does not pass through the connecting port (5) and collides with the inner surface of the vortex chamber (2), and coal is easily generated due to the excessive combustion in the vortex chamber (2).

[0173] In contrast, when the opening angle (α) is 4° to 7°, coal is not easily generated in the vortex chamber (2).

[0174] The coal formation in the vortex chamber (2) was investigated, in a basic case where the opening angle (α) was 4°. Figure 11 ) or 7° of the deformation example 9 ( Figure 12 In the first comparative example (0°), Figure 13 ), 1° second comparative example ( Figure 14 The third comparative example at 10° Figure 15 Compared to the previous method, less coal is produced in the vortex chamber (2).

[0175] exist Figure 11In the basic example shown in (A), the cone angle (β) of each fuel injection hole (9) is set to 12°.

[0176] exist Figure 12 In the modified example 9 of the fuel injection hole (9) shown in (A), the cone angle (β) of each fuel injection hole (9) is set to 18°.

[0177] In this engine, the cone angle (β) is preferably set to 12° to 18°.

[0178] When the cone angle (β) is less than 12°, the outlet opening (9b) is too small relative to the inlet opening (9a) of the fuel injection hole (9), and the fuel injection is hindered by a small amount of coal accumulated at the outlet of the fuel injection hole (9), which may reduce the accuracy of fuel injection control.

[0179] When the cone angle (β) is greater than 18°, the outlet opening (9b) is too large relative to the inlet opening (9a) of the fuel injection hole (9). The growth rate of coal deposits at the outlet of the fuel injection hole (9) increases, and fuel injection is hindered by a large amount of coal deposits. The accuracy of fuel injection control may be reduced.

[0180] In contrast, when the cone angle (β) is 12° to 18°, the growth rate of coal deposits at the outlet of the fuel injection hole (9) slows down, and the accuracy of fuel injection control is not easily reduced, provided that fuel injection is not hindered by a small amount of coal deposits.

[0181] The growth rate of coal deposits at the outlet of the fuel injection hole (9) was investigated in a basic example with a cone angle (β) of 12°. Figure 11 ), 18° of the deformation example 9 ( Figure 12 In the first comparative example (0°), Figure 13 ), 6° second comparative example ( Figure 14 The third comparative example at 24° Figure 15 Compared to the fuel injection hole (9), the growth rate of coal deposits at the outlet is slower.

[0182] like Figure 15 As in the third comparative example, when the cone angle (β) is greater than 18°, the growth rate of coal deposits at the outlet of the fuel injection hole (109) is faster; conversely, as... Figure 11 Basic examples Figure 12As in Variation 9, the reason for the slower growth rate when the cone angle (β) is 18° or less is presumed to be as follows. That is, in the former, a relatively large gap (109h) is formed around the fuel (113) injected at the outlet of the fuel injection hole (109), and a large amount of combustion gas containing coal flows into this large gap (109h), and the coal deposit grows rapidly. In contrast, in the latter, the gap (9h) around the fuel (13) injected at the outlet of the fuel injection hole (9) becomes an appropriate size, and the growth rate of the coal deposit and the removal rate of the coal deposit based on the injected fuel (13) are inversely related. It is presumed that the coal deposit growing at the outlet of the fuel injection hole (9) is immediately removed by the injected fuel.

[0183] like Figure 11 As shown in (A), in the basic example of the fuel injection hole (9), the angle (γ) between the injector central axis (7a) and the inner circumferential surface (9g) of each injection hole along the injector central axis (7a) is set to 1°.

[0184] like Figure 12 As shown in (A), in the modified example 9 of the fuel injection hole (9), the angle (γ) between the injector central axis (7a) and the inner circumferential surface (9g) of each injection hole along the injector central axis (7a) is set to 3°.

[0185] In this engine, the angle of attack (γ) is preferably set to 1° to 3°.

[0186] When the angle (γ) is less than 1°, a portion of the multiple injected fuels (13) tends to overlap, and coal is easily generated in the vortex chamber (2). When the opening angle (α) is greater than 3°, a large amount of injected fuel (13) collides with the inner surface of the vortex chamber (2) without passing through the connecting port (5), and coal is easily generated due to excessive combustion in the vortex chamber (2).

[0187] In contrast, when the angle (γ) is 1° to 3°, coal is not easily generated in the vortex chamber (2).

[0188] The coal formation in the vortex chamber (2) was investigated, in a basic case with an angle (γ) of 1°. Figure 11 ), 3° of the deformation example 9 ( Figure 12 In the first comparative example (0°), Figure 13 Compared to the comparative example of 4° (not shown), less coal was produced in the vortex chamber (2).

[0189] like Figure 11 As shown in (A), 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 corner (9f) that has not been chamfered.

[0190] exist Figure 12 In the modified example 9 of the fuel injection hole (9) shown in (A), the inlet opening edge (9e) of the fuel injection hole (9) also has a sharp pin corner (9f) that has not been chamfered.

[0191] In this engine, the inlet opening edge (9e) of the fuel injection hole (9) does not need to be chamfered due to the remaining sharp pin angle (9f) that has not been chamfered, making the manufacture of the fuel injector (7) easier.

[0192] In addition, in this engine, since the fuel injector (7) injects fuel into the vortex chamber (2), the fuel injection pressure is lower than that of a direct injection fuel injector, which is less likely to cause wear of the pin angle (9f) caused by the fuel injection pressure, and less likely to cause a decrease in fuel injection accuracy.

[0193] The aforementioned pin angle (9f) is a sharp-shaped opening edge with a radius of less than 0.1 mm.

[0194] Explanation of reference numerals in the attached figures

[0195] (1): Cylinder head; (1a): Through hole; (1b): Engine cooling air passage; (2): Swirl chamber; (3): Cylinder; (4): Main combustion chamber; (5): Connecting port; (6): Through hole; (7): Fuel injector; (7c): Main body; (7ca): Valve drive device; (7cb): Outer peripheral surface; (7d): Nozzle part; (7da): Valve body; (7db): Front end face; (7dc): Swirl guide surface; (10): Sleeve; (10a): Protruding end; (10b): Pressure surface; (11): Pressing force; (12): Washer; (12a): Pressing surface; (17): Adhesive; (18): Grease; (19): Sheet gasket; (20): Groove.

Claims

1. An electronic fuel injection diesel engine, The device comprises a cylinder (3), a cylinder head (1), a swirl chamber (2) within the cylinder head (1), a main combustion chamber (4) within the cylinder (3), a communication port (5) connecting the main combustion chamber (4) and the swirl chamber (2), a through hole (1a) within the cylinder head (1) facing the swirl chamber (2), and an electronic fuel injection type fuel injector (7) inserted into the through hole (1a), characterized in that, The electronic fuel injection diesel engine has a sleeve (10) protruding from the through hole (1a) outward from the cylinder head (1) and a pressure-receiving surface (10b) provided at the protruding end (10a) of the sleeve (10). The fuel injector (7) has a large-diameter main body (7c), a small-diameter nozzle (7d), and a pressing surface (7e) formed by the stepped portions of the main body (7c) and the nozzle (7d). The nozzle portion (7d) of the fuel injector (7) is inserted through the sleeve (10) into the insertion hole (1a). The fuel injector (7) is pressed towards the vortex chamber (2) by the pressing force (11). The pressing force (11) applied to the fuel injector (7) is received by the pressure-receiving surface (10b) of the sleeve (10) via the washer (12 from the pressing surface (7e) of the fuel injector (7). The nozzle section (7d) has a fuel injection hole (9) on the front end face (7db) facing the vortex chamber (2). Part or all of the front end face (7db) of the nozzle part (7d) protrudes into the vortex chamber (2) beyond the boundary between the through hole (1a) and the vortex chamber (2). The nozzle portion (7d) has a front end face (7db) with a spherical front end face (7dd) at its center. Multiple fuel injection holes (9) are arranged circumferentially along the spherical front end face (7dd) within the vortex chamber (2). The insertion hole (1a) and the nozzle portion (7d) are sealed between the inner peripheral surface of the insertion hole (1a) and the outer peripheral surface of the nozzle portion (7d) by a gas seal (7f) that is completely contained within the insertion hole (1a).

2. The electronic fuel injection diesel engine as described in claim 1, characterized in that, The nozzle section (7d) of the fuel injector (7) houses the valve body (7da), and the main body section (7c) of the fuel injector (7) houses the electronic components of the valve drive device (7ca) of the valve body (7da).

3. The electronic fuel injection diesel engine as described in claim 1 or 2, characterized in that, Equipped with engine cooling air duct (1b), The outer peripheral surface (7cb) of the main body (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).

4. The electronic fuel injection diesel engine as described in claim 1 or 2, characterized in that, The sleeve (10) is made of a different part from the cylinder head (1) and is installed on the cylinder head (1).

5. The electronic fuel injection diesel engine as described in claim 1 or 2, characterized in that, The pressing surface (12a) of the washer (12) and the pressure-receiving surface (10b) of the sleeve (10) are sealed by adhesive (17).

6. The electronic fuel injection diesel engine as described in claim 1 or 2, characterized in that, The pressing surface (12a) of the washer (12) and the pressure-receiving surface (10b) of the sleeve (10) are sealed by grease (18).

7. The electronic fuel injection diesel engine as described in claim 1 or 2, characterized in that, The pressing surface (12a) of the washer (12) and the pressure-receiving surface (10b) of the sleeve (10) are sealed by a sheet gasket (19).

8. The electronic fuel injection diesel engine as described in claim 1 or 2, characterized in that, Concentric circular or vortex-shaped grooves (20) extending circumferentially are formed on one or both of the pressure-bearing surface (10b) of the sleeve (10) and the pressing surface (12a) of the washer (12).

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