Fuel injection device, engine and vehicle

Abstract

The utility model belongs to the technical field of vehicles, and discloses a fuel injection device, an engine and a vehicle, one of one end, close to an injection end, of a heat conduction lining and a fuel injector is provided with a sealing convex part, the other one is provided with a sealing groove, and the sealing convex part and the sealing groove are hermetically connected in an interference fit mode. High-temperature mixed gas in a combustion chamber can be prevented from entering a gap between the end, away from the injection end, of the heat conduction lining and the fuel injector through a gap between the sealing convex part and the sealing groove, the area, in direct contact with the high-temperature mixed gas in the combustion chamber, of the heat conduction lining and the fuel injector is reduced, and the temperature of the heat conduction lining and the temperature of the fuel injector are reduced; in addition, the contact area between the heat conduction lining and the fuel injector can be increased through surface contact sealing fit of the sealing convex part and the sealing groove, the fuel injector can transfer heat of the fuel injector to the cylinder cover through the heat conduction lining in time, the carbon deposition amount of the injection end is reduced, and an injection hole of the injection end is prevented from being blocked by carbon deposition.

Description

Technical Field

[0001] The utility model relates to the technical field of vehicles, and in particular to a fuel injection device, an engine and a vehicle. Background Art

[0002] The fuel injection device is an important component of the engine and plays a vital role in the normal operation of the engine.

[0003] The cylinder head is provided with a mounting hole connected to the combustion chamber, and the fuel injection device is installed in the mounting hole. A bushing is provided between the fuel injection device and the inner wall of the mounting hole. The bushing is used to block the high-temperature mixture in the combustion chamber from entering the gap between the fuel injection device and the inner wall of the mounting hole; and the heat of the fuel injection device, especially the nozzle part, can be transferred to the bushing, and then transferred to the cylinder head by the bushing, thereby cooling the fuel injection device.

[0004] For diesel-gas dual-fuel engines, the lag time of fuel combustion in the combustion chamber is prolonged. When the engine is running at high load and high speed, the exhaust temperature increases sharply. The effect of cooling the fuel injection device using the above method is limited. After the engine has been running for a period of time, carbon deposits are likely to form at the spray holes of the fuel injection device, and the spray holes of the fuel injection device are gradually blocked, resulting in a decrease in the power and torque of the engine. Utility Model Content

[0005] The purpose of the utility model is to provide a fuel injection device, an engine and a vehicle, which can effectively reduce the rate of carbon deposition at the injection end, avoid the injection hole at the injection end from being blocked, and ensure the power and economy of the engine.

[0006] To achieve this purpose, the present invention adopts the following technical solutions:

[0007] A fuel injection device, comprising a fuel injector and a heat-conducting sleeve sleeved outside the fuel injector;

[0008] The heat-conducting bushing is provided with a sealing protrusion at one end close to the injection end of the fuel injector and one of the fuel injectors, and the other end is provided with a sealing groove. The sealing protrusion is arranged in the sealing groove and is surface-contacted and sealed with the sealing groove in an interference fit manner. The sealing protrusion is an annular protrusion extending circumferentially along the heat-conducting bushing.

[0009] As an implementation scheme of the above-mentioned fuel injection device, in a direction from one end of the heat-conducting bushing close to the injection end to the other end, the inner diameter of the sealing protrusion first increases and then decreases.

[0010] As an implementation plan for the above-mentioned fuel injection device, a first limiting surface is provided on the inner wall of an end of the heat-conducting bushing away from the injection end, and a second limiting surface facing the first limiting surface is provided on the outer wall of the fuel injector. The first limiting surface is closer to the injection end than the second limiting surface along the axial direction of the heat-conducting bushing, and a sealing gasket is sandwiched between the first limiting surface and the second limiting surface.

[0011] As an implementation scheme of the above fuel injection device, the first limiting surface and the second limiting surface are both annular surfaces extending along the circumference of the heat-conducting bushing, and the sealing gasket is an annular flat plate structure extending along the circumference of the heat-conducting bushing;

[0012] And / or, the sealing protrusion is an annular protrusion extending along the circumference of the heat-conducting bushing, and the sealing groove is an annular groove extending along the circumference of the heat-conducting bushing.

[0013] As an implementation plan of the above-mentioned fuel injection device, the heat-conducting bushing includes a first bushing section located between the first limiting surface and the sealing protrusion, and the fuel injector includes a first injection section located between the first limiting surface and the sealing protrusion; the first bushing section is clearance-fitted with the first injection section.

[0014] As an implementation scheme of the above fuel injection device, the difference between the inner diameter of the first bushing segment and the outer diameter of the first injection segment is L, and 0.15 mm ≤ L / 2 ≤ 0.3 mm.

[0015] As a possible implementation of the above fuel injection device, the fuel injector has two injection channels, one of which is used to inject fuel, and the other of which is used to inject a fuel different from the fuel.

[0016] In order to achieve the above-mentioned purpose, the present invention also provides an engine, including a cylinder head, a cylinder body connected to the cylinder head, a piston axially movably mounted on the cylinder body, and a fuel injection device as described in any of the above schemes, a combustion chamber is surrounded by the cylinder head, the piston and the cylinder body, an injection mounting hole connected to the combustion chamber is provided on the cylinder head, and the heat-conducting bushing is installed in the injection mounting hole.

[0017] As a possible implementation scheme of the above engine, at least one of the combustion chambers is equipped with at least two of the fuel injection devices.

[0018] In order to achieve the above-mentioned object, the present invention also provides a vehicle, comprising the above-mentioned engine.

[0019] The beneficial effects of the present invention are as follows: a sealing protrusion is provided on one of the ends of the heat-conducting bushing close to the injection end and the fuel injector, and a sealing groove is provided on the other end. By arranging the sealing protrusion in the sealing groove and sealingly connecting it with the sealing groove in an interference fit manner, the high-temperature mixture in the combustion chamber can be prevented from entering the gap between the end of the heat-conducting bushing away from the injection end and the fuel injector through the gap between the sealing protrusion and the sealing groove, thereby reducing the area of ​​direct contact between the heat-conducting bushing and the fuel injector with the high-temperature mixture in the combustion chamber, and reducing the temperature of the heat-conducting bushing and the fuel injector. Moreover, the end of the fuel injector provided with the injection end is directly in contact with the high-temperature mixture, and the temperature of the heat-conducting bushing and the fuel injector is relatively high. The heat on the fuel injector can be transferred to the cylinder head through the heat-conducting bushing to realize the heat dissipation of the fuel injector. The sealing fit of the sealing protrusion and the sealing groove in surface contact can increase the contact area between the heat-conducting bushing and the fuel injector, which is beneficial for the fuel injector to transfer its own heat to the cylinder head through the heat-conducting bushing in time, thereby reducing the amount of carbon deposits at the injection end and preventing the injection hole at the injection end from being blocked by carbon deposits. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a cross-sectional view of the fuel injection device provided by an embodiment of the present utility model when installed on a cylinder head.

[0021] In the picture:

[0022] 1. Thermally conductive bushing; 11. Sealing convex portion; 2. Fuel injector; 3. Sealing gasket;

[0023] 20. Cylinder head. DETAILED DESCRIPTION

[0024] The present invention will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are intended only to illustrate the present invention and are not intended to limit the present invention. It should also be noted that, for ease of description, the accompanying drawings only illustrate portions relevant to the present invention, not all of its components.

[0025] In the description of this utility model, unless otherwise specified or limited, the terms "connected," "connect," and "fixed" should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this utility model based on the specific circumstances.

[0026] In the present invention, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Moreover, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0027] In the description of this embodiment, the terms "upper," "lower," "right," and other orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely for ease of description and simplified operation. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on the present invention. Furthermore, the terms "first" and "second" are used solely for descriptive purposes and have no special meaning.

[0028] like Figure 1 As shown, an embodiment of the present invention provides a fuel injection device and an engine. The engine includes a cylinder head 20, a cylinder block connected to the cylinder head 20, a piston axially movably mounted to the cylinder block, and a fuel injection device. A combustion chamber is defined between the cylinder head 20, the piston, and the cylinder block. The cylinder head 20 is provided with an injection mounting hole communicating with the combustion chamber. The fuel injection device is disposed in the injection mounting hole and is configured to inject fuel into the combustion chamber. It should be noted that the number of combustion chambers, i.e., the number of cylinders in the engine, is determined by the engine type and is not specifically defined herein.

[0029] The following uses a fuel injection device capable of injecting two fuels as an example. This fuel injection device has two injection channels, each with an injection hole formed at one end. For ease of description, the two injection channels are referred to as the first injection channel and the second injection channel, respectively. The injection hole of the first injection channel is referred to as the first injection hole, and the injection hole of the second injection channel is referred to as the second injection hole. The first injection channel injects a first fuel, such as diesel or gasoline, into the combustion chamber through the first injection hole. The second injection channel injects a second fuel, different from the first fuel, such as natural gas or methanol, into the combustion chamber through the second injection hole. The first fuel is primarily used to ignite the second fuel.

[0030] It should be noted that the fuel injection device may also be a single fuel injector, that is, having only one injection channel, such as a fuel injector.

[0031] like Figure 1As shown, the fuel injection device includes a fuel injector 2 and a heat-conducting sleeve 1 mounted on the outside of the fuel injector 2. Specifically, the heat-conducting sleeve 1 is located between the inner circumferential wall of the injection mounting hole and the outer wall of the fuel injector 2. The injection end of the fuel injector 2 passes through the heat-conducting sleeve 1 and extends into the combustion chamber to prevent the heat-conducting sleeve 1 from affecting the fuel in the injection channel from being sprayed into the combustion chamber through the injection hole.

[0032] The end of the thermally conductive bushing 1 closest to the injection end of the fuel injection device and one of the fuel injectors 2 are provided with a sealing protrusion 11, and the other end is provided with a sealing groove. The sealing protrusion 11 is disposed within the sealing groove and is in surface contact and sealed connection with the sealing groove through an interference fit. It should be noted that the injection end of the injection device refers to the end of the injection device where the injection hole is located.

[0033] The fuel injection device provided by the embodiment of the present utility model is provided with a sealing convex portion 11 on one end of the heat-conducting bushing 1 close to the injection end and the fuel injector 2, and a sealing groove on the other end. The sealing convex portion 11 is arranged in the sealing groove and is in surface contact and sealed connection with the sealing groove in the form of an interference fit. It can prevent the high-temperature mixed gas in the combustion chamber from entering the gap between the end of the heat-conducting bushing 1 away from the injection hole and the fuel injector 2 through the gap between the sealing convex portion 11 and the sealing groove, thereby reducing the direct contact between the heat-conducting bushing 1 and the fuel injector 2 and the high-temperature mixed gas in the combustion chamber. The area of ​​the gas can be increased, thereby reducing the temperature of the heat-conducting bushing 1 and the fuel injector 2; the injection end of the fuel injector 2 is in direct contact with the high-temperature mixture and has a high temperature. The heat on the fuel injector 2 can be transferred to the cylinder head 20 through the heat-conducting bushing 1 to achieve heat dissipation of the fuel injector 2, and the sealing protrusion 11 and the sealing groove are in contact and sealed, which can increase the contact area between the heat-conducting bushing 1 and the fuel injector 2, which is beneficial for the fuel injector 2 to transfer its own heat to the cylinder head 20 through the heat-conducting bushing 1 in time, thereby reducing the amount of carbon deposits on the injection end and avoiding the injection end being blocked by carbon deposits.

[0034] Furthermore, the sealing protrusion 11 is a small, invisible convex point provided on the inner wall of the heat-conducting bushing 1, and the sealing groove is provided on the outer peripheral wall of the fuel injector 2. This facilitates the disassembly of the fuel injection device and avoids damage to the fuel injection device during the disassembly process.

[0035] In other embodiments, the sealing protrusion 11 may be provided on the outer peripheral wall of the fuel injector 2 , and the sealing groove may be provided on the inner peripheral wall of the heat-conducting bushing 1 .

[0036] Furthermore, the inner diameter of the sealing protrusion 11 increases and then decreases from one end of the thermally conductive bushing 1 closest to the injection end to the other end. For example, the thermally conductive bushing 1 is an arc-shaped protrusion. This arrangement ensures an interference fit between the sealing protrusion 11 and the sealing groove, while ensuring easy disassembly of the fuel injector 2 and reducing the possibility of damage to the fuel injector 2 during disassembly.

[0037] Furthermore, a first limiting surface is provided on the inner wall of the end of the thermal bushing 1 away from the injection end, and a second limiting surface is provided on the outer wall of the fuel injector 2, facing the first limiting surface. The first limiting surface is closer to the injection hole than the second limiting surface along the axial direction of the thermal bushing 1. A sealing gasket 3 is sandwiched between the first and second limiting surfaces. This achieves a sealed connection between the end of the thermal bushing 1 away from the injection end and the fuel injector 2, preventing condensed water in the cylinder head 20 from entering the combustion chamber through the gap between the thermal bushing 1 and the fuel injector 2. It also reduces the probability of damage to the sealing gasket 3 during disassembly of the fuel injector 2, thereby extending its service life.

[0038] Specifically, the inner hole of the thermally conductive bushing 1 is a stepped hole, which includes a first hole and a second hole. The aperture of the first hole is larger than the aperture of the second hole. The first hole and the second hole are connected to form a first limiting surface. The first limiting surface and the second limiting surface are both annular surfaces extending along the circumference of the thermally conductive bushing 1. The sealing gasket 3 is an annular flat plate structure extending along the circumference of the thermally conductive bushing 1.

[0039] Exemplarily, the sealing gasket 3 is a copper structure. Such a configuration is conducive to the heat-conducting bushing 1 transferring its own heat to the cylinder head 20 through the sealing gasket 3 .

[0040] Furthermore, the thermally conductive bushing 1 includes a first bushing segment positioned between the first limiting surface and the sealing protrusion 11, and the fuel injector 2 includes a first injection segment positioned between the first limiting surface and the sealing protrusion 11. The first bushing segment and the first injection segment are loosely fitted. This arrangement facilitates assembly and disassembly of the fuel injector 2 and prevents scratches on the fuel injector 2 during assembly and disassembly.

[0041] Furthermore, the difference between the inner diameter of the first bushing section and the outer diameter of the first injection section is L, and 0.15 mm ≤ L / 2 ≤ 0.3 mm. L is minimized as much as possible while ensuring ease of assembly and disassembly of the fuel injector 2, and avoiding increased manufacturing costs of the fuel injection device due to excessive machining accuracy of the inner bore wall of the thermal bushing 1 and the outer wall of the fuel injector 2.

[0042] It should be noted that L can be any value between 0.15mm and 0.3mm, such as 0.15mm, 0.16mm, 0.17mm, 0.18mm, 0.19mm, 0.20mm, 0.11mm, 0.22mm, 0.11mm, 0.24mm, 0.25mm, 0.26mm, 0.27mm, 0.28mm, 0.29mm, and 0.30mm.

[0043] Furthermore, the sealing protrusion 11 is spaced apart from the end surface of the heat-conducting bushing 1 near the injection end. It should be noted that the spacing between the sealing protrusion 11 and the end surface of the heat-conducting bushing 1 near the injection end is caused by processing. On the basis of meeting processing requirements, the sealing protrusion 11 should be as close as possible to the end surface of the heat-conducting bushing 1 near the injection end to reduce the area of ​​direct contact between the heat-conducting bushing 1 and the high-temperature mixture in the combustion chamber, thereby reducing the temperature of the heat-conducting bushing 1.

[0044] Furthermore, the thermally conductive bushing 1 further comprises a second bushing segment located at an end of the sealing protrusion 11 away from the first limiting surface, and the fuel injector 2 comprises a second injection segment spaced apart from the second bushing segment. This arrangement facilitates assembly and disassembly of the fuel injector 2 and prevents scratches on the fuel injector 2 during assembly and disassembly.

[0045] It should be noted that the difference between the inner diameter of the second bushing section and the outer diameter of the second injection section is L.

[0046] Furthermore, at least one combustion chamber is equipped with at least two fuel injection devices. When the engine is running, the at least two fuel injection devices can be controlled to work alternately according to power demand, so as to avoid a single fuel injection device working in a high temperature environment for a long time and extend the service life of the fuel injection device.

[0047] This embodiment further provides a vehicle including the above-mentioned engine. The vehicle has the same technical effects as the above-mentioned fuel injection device, and the details will not be repeated here.

[0048] Obviously, the above-described embodiments of the present invention are merely examples for the purpose of clearly illustrating the present invention and are not intended to limit the manner in which the present invention is to be implemented. A person skilled in the art would be able to make various obvious changes, readjustments, and substitutions without departing from the scope of protection of the present invention. It is not necessary and impossible to enumerate all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the claims of the present invention.

Claims

1. A fuel injection device, characterized in that It comprises a fuel injector (2) and a heat-conducting bushing (1) sleeved outside the fuel injector (2); The heat-conducting bushing (1) is provided with a sealing protrusion (11) at one end close to the injection end of the fuel injector (2) and one of the fuel injectors (2), and the other end is provided with a sealing groove. The sealing protrusion (11) is arranged in the sealing groove and is connected to the sealing groove in a surface contact sealing manner in an interference fit manner. The sealing protrusion (11) is an annular protrusion extending along the circumference of the heat-conducting bushing (1).

2. The fuel injection device according to claim 1, characterized in that In a direction from one end of the heat-conducting bushing (1) close to the injection end to the other end, the inner diameter of the sealing protrusion (11) first increases and then decreases.

3. The fuel injection device according to claim 1, characterized in that A first limiting surface is provided on the inner wall of an end of the heat-conducting bushing (1) away from the injection end, and a second limiting surface facing the first limiting surface is provided on the outer wall of the fuel injector (2). The first limiting surface is closer to the injection end than the second limiting surface along the axial direction of the heat-conducting bushing (1), and a sealing gasket (3) is sandwiched between the first limiting surface and the second limiting surface.

4. The fuel injection device according to claim 3, characterized in that The first limiting surface and the second limiting surface are both annular surfaces extending along the circumference of the heat-conducting bushing (1), and the sealing gasket (3) is an annular flat plate structure extending along the circumference of the heat-conducting bushing (1); And / or, the sealing protrusion (11) is an annular protrusion extending along the circumference of the heat-conducting bushing (1), and the sealing groove is an annular groove extending along the circumference of the heat-conducting bushing (1).

5. The fuel injection device according to claim 3, characterized in that The heat-conducting bushing (1) comprises a first bushing section located between the first limiting surface and the sealing protrusion (11); the fuel injector (2) comprises a first injection section located between the first limiting surface and the sealing protrusion (11); the first bushing section and the first injection section are clearance-matched.

6. The fuel injection device according to claim 5, characterized in that A difference between an inner diameter of the first bushing segment and an outer diameter of the first injection segment is L, and 0.15 mm ≤ L / 2 ≤ 0.3 mm.

7. The fuel injection device according to any one of claims 1 to 6, characterized in that The fuel injector (2) has two injection channels, one of which is used to inject fuel and the other is used to inject fuel different from the fuel.

8. An engine, characterized in that The invention comprises a cylinder head (20), a cylinder body connected to the cylinder head (20), a piston axially movably mounted on the cylinder body, and a fuel injection device as claimed in any one of claims 1 to 7, wherein a combustion chamber is surrounded by the cylinder head (20), the piston and the cylinder body, an injection mounting hole communicating with the combustion chamber is provided on the cylinder head (20), and the heat-conducting bushing (1) is mounted on the injection mounting hole.

9. The engine according to claim 8, characterized in that At least one of the combustion chambers is equipped with at least two of the fuel injection devices.

10. A vehicle, characterized in that Including the engine according to claim 8 or 9.

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