Precombustion chamber assembly and precombustion chamber cooling system

Abstract

The present invention belongs to the technical field of engines and discloses a precombustion chamber assembly and a precombustion chamber cooling system. The precombustion chamber assembly includes a cooling water jacket and a precombustion chamber. The cooling water jacket is arranged under the cylinder head, and the cooling water jacket is not connected to the cylinder head water jacket, so as to ensure that the cooling water jacket is connected at the cooling ring groove of the precombustion chamber. The cooling water jacket is provided with a mounting hole, and the precombustion chamber is installed in the mounting hole. A cooling ring groove is provided on the outer peripheral surface of the precombustion chamber, and the cooling ring groove is connected to the cooling channel. The coolant enters the cooling channel from the cylinder head, flows around the precombustion chamber and then flows out from the intake side, so as to realize cooling of the upper part of the exhaust duct and the precombustion chamber. The cooling water jacket does not need to increase additional external space, but instead forms a cooling space for the precombustion chamber through the coordinated design and installation of the precombustion chamber and the cylinder head. The cooling water jacket is particularly suitable for small gasoline engines with limited layout space. At the same time, it will not increase the manufacturing cost of the cylinder head, and can ensure that the precombustion chamber has a simple structure and reliable operation.

Description

Technical Field

[0001] The present invention relates to the technical field of engines, and in particular to a pre-combustion chamber assembly and a pre-combustion chamber cooling system. Background Art

[0002] The entire combustion area is divided into a main combustion chamber and a pre-chamber. When the engine is running, fuel is first injected into the pre-chamber, where it is ignited by a spark plug inside the pre-chamber. This rapidly increases the pressure in the pre-chamber, forcing the high-temperature fuel gas into the main combustion chamber through a channel in the form of a flame jet. Within the main combustion chamber, multiple flames are generated, igniting the lean mixture within. This method allows the flame to penetrate deeper into the main combustion chamber, contacting more of the unburned mixture, increasing ignition energy, and enhancing airflow disturbance within the combustion chamber. Compared to traditional spark plug ignition, the pre-chamber significantly increases combustion velocity, advances the center of gravity of combustion, achieves lean burn, and improves engine thermal efficiency.

[0003] Internal combustion engines with pre-combustion chambers have not yet been widely used in commercial production in the automotive industry. There are two main reasons for this: First, many pre-combustion chambers do not have special cooling measures. Long-term operation of the pre-combustion chamber at high temperatures will cause many problems. For example, excessively high temperatures will greatly shorten the service life of the spark plugs in the pre-combustion chamber, and may also cause the nozzles of the pre-combustion chamber to melt or be damaged due to overheating. It may also cause pre-ignition due to the formation of hot spots due to local excessive temperatures. Second, some pre-combustion chambers are equipped with special cooling passages, but this leads to a complex structure of the pre-combustion chamber, increased costs, and larger sizes, making it impossible to arrange and apply it on small gasoline engines. In addition, the structure is complex, the sealing requirements are high, and reliability is also a problem.

[0004] Therefore, a pre-combustion chamber assembly and a pre-combustion chamber cooling system are urgently needed to solve the above problems. Summary of the Invention

[0005] The purpose of the present invention is to provide a pre-combustion chamber assembly and a pre-combustion chamber cooling system, which does not require additional external space, does not increase the manufacturing cost of the cylinder head, and does not affect the manufacturing process. This structure can ensure that the pre-combustion chamber structure is simple and the operation is reliable.

[0006] In order to solve the above problems existing in the prior art, the present invention adopts the following technical solutions:

[0007] A pre-combustion chamber assembly is mounted on the cylinder head, and the pre-combustion chamber assembly includes:

[0008] a cooling water jacket, the cooling water jacket being disposed below the cylinder head, the cooling water jacket having a cooling channel for circulating coolant, and the cooling water jacket being provided with a mounting hole;

[0009] A pre-combustion chamber is installed in the installation hole, and a cooling ring groove is opened on the outer peripheral surface of the pre-combustion chamber, and the cooling ring groove is connected to the cooling channel.

[0010] Preferably, the pre-combustion chamber includes a pre-combustion chamber body and a sealing protrusion, the pre-combustion chamber body is installed in the mounting hole, the sealing protrusion is protruded from the outer peripheral surface of the pre-combustion chamber body, and along the outer peripheral direction of the pre-combustion chamber body, the sealing protrusion is sealed and connected to the inner wall of the mounting hole.

[0011] Preferably, the pre-combustion chamber further includes a gasket, which is sleeved on the pre-combustion chamber body and clamped between the cylinder head and the sealing protrusion.

[0012] Preferably, the pre-combustion chamber also includes a sealing ring, and the outer peripheral surface of the pre-combustion chamber body is also provided with a mounting groove, the mounting groove is located above the cooling ring groove, the sealing ring is arranged in the mounting groove, and the outer ring of the sealing ring abuts against the through hole of the cylinder head.

[0013] Preferably, the cooling water jacket comprises a water inlet and a water outlet, a plurality of the water outlets are provided, and both ends of the cooling channel are respectively connected to the water inlet and the plurality of the water outlets.

[0014] Preferably, the pre-combustion chamber assembly further includes a pressing sleeve, the cylinder head is provided with a connecting hole, the pressing sleeve is arranged in the connecting hole, and the pressing sleeve is pressed tightly against the pre-combustion chamber body.

[0015] Preferably, the outer peripheral surface of the pressing sleeve is provided with an external thread, the hole wall of the connecting hole is provided with an internal thread, and the pressing sleeve is threadedly connected to the connecting hole.

[0016] Preferably, the diameter of the connecting hole is not larger than the diameter of the mounting hole, and the width of the press-fitting surface between the pressing sleeve and the pre-combustion chamber body is larger than 1.5 mm.

[0017] To achieve the above-mentioned purpose, the present invention also provides a pre-combustion chamber cooling system, including a thermostat, a water temperature sensor and the above-mentioned pre-combustion chamber assembly, wherein the water temperature sensor is connected to the cooling water jacket signal, and the cooling water jacket is connected to the thermostat signal.

[0018] Preferably, the pre-combustion chamber cooling system further comprises a water pump, which is connected to the cooling water jacket and is signal-connected to the thermostat and the water temperature sensor.

[0019] The beneficial effects of the present invention are:

[0020] The precombustion chamber assembly provided by the present invention features a cooling water jacket integrated beneath the cylinder head. This cooling water jacket is independent of the cylinder head water jacket, ensuring connectivity with the cooling water jacket at the precombustion chamber's cooling annular groove. The cooling water jacket includes a cooling channel for circulating coolant. A cooling annular groove is defined on the outer circumference of the precombustion chamber, connecting the cooling channel. An annular cooling water cavity is formed around the precombustion chamber. Coolant enters the cooling channel from the cylinder head, circulates around the precombustion chamber, and exits from the intake side, cooling the upper exhaust duct and the precombustion chamber. This cooling water jacket eliminates the need for additional external space. Instead, the precombustion chamber and cylinder head are designed and installed together to create a cooling space for the precombustion chamber. This makes it particularly suitable for small gasoline engines with limited space. Furthermore, the cylinder head does not increase manufacturing costs, as the cylinder head is already a casting, requiring the main water jacket for the engine's main combustion chamber to be cast internally. Adding a cooling water jacket does not affect the manufacturing process. This design ensures a simple and reliable precombustion chamber.

[0021] The pre-combustion chamber cooling system provided by the present invention includes a thermostat, a water temperature sensor, and a water pump. The water temperature sensor is connected to the cooling water jacket signal, and the cooling water jacket is connected to the thermostat signal. The water pump is connected to the cooling water jacket and is connected to the thermostat and the water temperature sensor signal. The water pump is fixed to the engine. Based on the temperature model of the engine load and speed, the water temperature sensor detects the temperature of the cylinder head. When the temperature of the cylinder head is too high, the outlet flow of the water pump is adjusted in real time to increase the flow and flow rate of the coolant, thereby adjusting the cooling temperature of the cooling water jacket, achieving precise control of the pre-combustion chamber temperature, and thus achieving control of the combustion boundary conditions, achieving combustion under the most ideal conditions, and improving combustion efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 is a cross-sectional view of a pre-combustion chamber according to an embodiment of the present invention;

[0023] Figure 2 Schematic diagram of the structure of the cooling water jacket in an embodiment of the present invention;

[0024] Figure 3 A cross-sectional view of a cylinder head and a cooling water jacket in an embodiment of the present invention;

[0025] Figure 4 A top view of a press sleeve in an embodiment of the present invention;

[0026] Figure 5 Schematic diagram of the pre-combustion chamber cooling system in an embodiment of the present invention.

[0027] Reference numerals:

[0028] 100, cylinder head; 101, connection hole; 102, cylinder head water jacket;

[0029] 1. Cooling water jacket; 11. Cooling channel; 12. Mounting hole; 13. Water inlet; 14. Water outlet;

[0030] 2. Precombustion chamber; 21. Cooling ring groove; 22. Precombustion chamber body; 23. Sealing protrusion; 24. Gasket; 25. Sealing ring; 26. Mounting groove; 27. Nozzle hole; 28. Combustion space;

[0031] 3. Press sleeve. DETAILED DESCRIPTION

[0032] The present invention will be further described in detail below with reference to the accompanying drawings and examples. It will 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 structures.

[0033] In the description of the present invention, unless otherwise expressly specified or limited, the terms "connected," "connected," and "fixed" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and 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 the present invention in specific circumstances.

[0034] 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. Furthermore, 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.

[0035] In the description of this embodiment, terms such as "upper," "lower," "left," and "right" are used to refer to positions or locations based on those shown in the accompanying drawings. These terms are intended solely to facilitate description and simplify operation, and are not intended to indicate or imply that the devices or components referred to must have, 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.

[0036] Many pre-combustion chambers do not have special cooling measures, and long-term operation of the pre-combustion chamber at high temperatures will cause many problems. For example, if the temperature is too high, the service life of the spark plug in the pre-combustion chamber will be greatly shortened, and the nozzle of the pre-combustion chamber will melt or be damaged due to overheating. It may also cause pre-ignition due to the formation of hot spots due to local excessive temperature. In addition, some pre-combustion chambers are provided with special cooling passages, but this leads to a complex structure of the pre-combustion chamber, increased costs, and larger sizes, which cannot be arranged and applied on small gasoline engines. Moreover, the structure is complex, the sealing requirements are high, and reliability is also a problem. In this regard, the present embodiment provides a pre-combustion chamber assembly, which does not require additional external space, does not increase the manufacturing cost of the cylinder head, and does not affect the manufacturing process. This structure can ensure that the pre-combustion chamber structure is simple and the operation is reliable.

[0037] like Figure 1-Figure 5 As shown, in this embodiment, the pre-combustion chamber assembly is installed on the cylinder head 100, and the pre-combustion chamber assembly includes a cooling water jacket 1 and a pre-combustion chamber 2. The cooling water jacket 1 is arranged below the cylinder head 100, and has a cooling channel 11 for circulating coolant. The cooling water jacket 1 is provided with a mounting hole 12, and the pre-combustion chamber 2 is mounted in the mounting hole 12. The outer peripheral surface of the pre-combustion chamber 2 is provided with a cooling ring groove 21, and the cooling ring groove 21 is connected to the cooling channel 11. Specifically, the pre-combustion chamber 2 adopts a stepped structure, and from bottom to top are the flame nozzle 27, the combustion space 28, the oil-gas mixture inlet, the spark plug threaded hole and the cooling ring groove 21. The pre-combustion chamber 2 is designed in coordination with the cylinder head 100. According to calculation and analysis, the cooling ring groove 21 is located 1 / 4 to 1 / 2 of the spark plug installation position. A cooling water jacket 1 is integrated below the cylinder head 100. This cooling water jacket 1 is not connected to the cylinder head water jacket 102, ensuring that the cooling water jacket 1 is connected to the cooling ring groove 21 of the precombustion chamber 2. The cooling water jacket 1 is connected to the cooling ring groove 21, forming an annular cooling water cavity around the precombustion chamber 2. Coolant enters the cooling channel 11 from the cylinder head 100, circling the precombustion chamber 2 before flowing out from the intake side, cooling the upper exhaust duct and the precombustion chamber 2. This cooling water jacket 1 does not require additional external space. Instead, it forms the cooling space for the precombustion chamber 2 through the coordinated design and installation of the precombustion chamber 2 and the cylinder head 100. It is particularly suitable for small gasoline engines with limited layout space. At the same time, the cylinder head 100 will not bring about an increase in manufacturing costs, because the cylinder head 100 is originally a casting, and the main water jacket of the main combustion chamber of the engine needs to be cast inside. The design of adding a layer of cooling water jacket 1 does not affect the manufacturing process. For the pre-combustion chamber 2, this structure can ensure that the pre-combustion chamber 2 has a simple structure and reliable operation.

[0038] Further, continue to refer to Figure 1-Figure 5The pre-combustion chamber 2 includes a pre-combustion chamber body 22 and a sealing protrusion 23. The pre-combustion chamber body 22 is mounted in the mounting hole 12. The sealing protrusion 23 is protruding from the outer circumference of the pre-combustion chamber body 22. Along the outer circumference of the pre-combustion chamber body 22, the sealing protrusion 23 is sealed to the inner wall of the mounting hole 12. Specifically, a sealing protrusion 23 is provided below the cooling ring groove 21 for sealing with the cylinder head 100, preventing the coolant in the cooling ring groove 21 from leaking downward along the outer circumferential wall of the pre-combustion chamber 2, and achieving good sealing performance.

[0039] Further, continue to refer to Figure 1-Figure 5 The pre-combustion chamber 2 further includes a gasket 24, which is sleeved on the pre-combustion chamber body 22 and sandwiched between the cylinder head 100 and the sealing protrusion 23. Specifically, the gasket 24 is made of metal material. The cooling water jacket 1 is connected to the cooling ring groove 21, forming an annular cooling water cavity around the pre-combustion chamber body 22. The lower part of the cooling water cavity is sealed by the metal gasket 24. Since there is a clearance fit between the lower part of the pre-combustion chamber 2 and the cylinder head 100, the gasket 24 not only seals the coolant, but also seals the gas in the combustion space 28 to prevent it from entering the cooling water jacket 1 of the pre-combustion chamber 2. At the same time, the gas temperature is extremely high, and rubber cannot be used for sealing.

[0040] Further, continue to refer to Figure 1-Figure 5 The pre-combustion chamber 2 also includes a sealing ring 25. A mounting groove 26 is defined on the outer circumference of the pre-combustion chamber body 22. The mounting groove 26 is located above the cooling ring groove 21. The sealing ring 25 is positioned within the mounting groove 26, with the outer ring of the sealing ring 25 abutting against the through-hole of the cylinder head 100. Specifically, the mounting groove 26 is defined above the pre-combustion chamber body 22 for mounting the sealing ring 25. The mounting groove 26, when assembled with the cylinder head 100, seals the coolant.

[0041] Further, continue to refer to Figure 1-Figure 5 The cooling water jacket 1 includes a water inlet 13 and a water outlet 14. A plurality of water outlets 14 are provided, and both ends of the cooling channel 11 are connected to the water inlet 13 and the plurality of water outlets 14, respectively. Specifically, the coolant enters through the water inlet 13, circulates around the pre-combustion chamber 2, passes through the cooling channel 11, and flows out of the water outlet 14, thereby cooling the pre-combustion chamber 2.

[0042] Further, continue to refer to Figure 1-Figure 5The pre-combustion chamber assembly also includes a press sleeve 3. The cylinder head 100 is provided with a connecting hole 101. The press sleeve 3 is provided in the connecting hole 101 and is pressed against the pre-combustion chamber body 22. Specifically, the outer peripheral surface of the press sleeve 3 is provided with an external thread, and the hole wall of the connecting hole 101 is provided with an internal thread. The press sleeve 3 is threadedly connected to the connecting hole 101. Since the lower end face of the pre-combustion chamber body 22 and the cylinder head 100 are sealed with a metal gasket 24, sufficient pressing force must be provided. The pressing force is provided by the press sleeve 3. The press sleeve 3 is tightened in the connecting hole 101 in the cylinder head 100 and cooperates with the upper end face of the pre-combustion chamber body 22 to press the pre-combustion chamber 2. Preferably, the inner diameter of the press sleeve 3 is larger than the outer diameter of the spark plug installation position to facilitate the installation and removal of the spark plug.

[0043] Further, continue to refer to Figure 1-Figure 5 , the aperture of the connecting hole 101 is not larger than the aperture of the mounting hole 12, and the width of the press-fit surface between the press sleeve 3 and the pre-combustion chamber body 22 is greater than 1.5 mm. Specifically, when designing the external thread diameter of the press sleeve 3, the structure of the cylinder head 100 should be combined to ensure the feasibility of machining the cylinder head 100. Because the upper part of the mounting groove 26 of the sealing ring 25 of the pre-combustion chamber 2 needs to be machined into the threaded hole of the press sleeve 3, when designing the outer diameter of the press sleeve 3, it is necessary to ensure that the diameter of the mounting groove 26 of the sealing ring 25 is not larger than the diameter of the threaded hole of the press sleeve 3. A chamfer is designed on the lower end face of the press sleeve 3 to provide a guide for the installation of the press sleeve 3. When designing the size of the chamfer, it is necessary to ensure that the width of the press-fit surface between the pre-combustion chamber 2 and the press sleeve 3 is greater than 1.5 mm. Specific installation of the press sleeve 3: the upper part is designed with an internal flower structure, which is tightened with special tools and does not require additional space.

[0044] The present invention also provides a pre-combustion chamber cooling system, including a thermostat, a water temperature sensor and the above-mentioned pre-combustion chamber assembly, wherein the water temperature sensor is connected to the cooling water jacket 1 by signal, and the cooling water jacket 1 is connected to the thermostat by signal. Specifically, the pre-combustion chamber cooling system also includes a water pump, which is connected to the cooling water jacket 1 and is connected to the thermostat and the water temperature sensor by signal. The water pump is fixed on the engine, and the water temperature sensor detects the temperature of the cylinder head 100 based on the temperature model of the engine load and speed. When the temperature of the cylinder head 100 is too high, the outlet flow of the water pump is adjusted in real time to increase the flow and flow rate of the coolant, thereby adjusting the cooling temperature of the cooling water jacket 1 and achieving precise control of the temperature of the pre-combustion chamber 2, thereby achieving control of the combustion boundary conditions, achieving combustion under the most ideal conditions, and improving combustion efficiency.

[0045] Obviously, the above embodiments of the present invention are merely examples for the purpose of clearly illustrating the present invention and are not intended to limit the embodiments of the present invention. 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 pre-combustion chamber assembly, mounted on a cylinder head (100), characterized in that: The pre-combustion chamber assembly comprises: A cooling water jacket (1), the cooling water jacket (1) being arranged below the cylinder head (100), the cooling water jacket (1) having a cooling channel (11) for circulating a coolant, and the cooling water jacket (1) being provided with a mounting hole (12); A precombustion chamber (2), the precombustion chamber (2) being mounted on the mounting hole (12), a cooling ring groove (21) being provided on the outer peripheral surface of the precombustion chamber (2), the cooling ring groove (21) being connected to the cooling channel (11), forming an annular cooling water cavity around the precombustion chamber (2), the coolant entering the cooling channel (11) from the cylinder head 100, flowing out from the intake side after circulating around the precombustion chamber (2), thereby cooling the upper part of the exhaust duct and the precombustion chamber (2); The pre-combustion chamber (2) comprises a pre-combustion chamber body (22) and a sealing protrusion (23); the pre-combustion chamber body (22) is mounted on the mounting hole (12); the sealing protrusion (23) is convexly arranged on the outer peripheral surface of the pre-combustion chamber body (22); along the outer peripheral direction of the pre-combustion chamber body (22), the sealing protrusion (23) is sealed and connected to the inner wall of the mounting hole (12); The pre-combustion chamber (2) further comprises a gasket (24), wherein the gasket (24) is sleeved on the pre-combustion chamber body (22), and the gasket (24) is sandwiched between the cylinder head (100) and the sealing protrusion (23); The cooling water jacket (1) comprises a water inlet (13) and a water outlet (14), a plurality of the water outlets (14) are provided, and both ends of the cooling channel (11) are respectively connected to the water inlet (13) and the plurality of the water outlets (14).

2. The pre-combustion chamber assembly according to claim 1, characterized in that: The pre-combustion chamber (2) further includes a sealing ring (25), and the outer peripheral surface of the pre-combustion chamber body (22) is further provided with a mounting groove (26), wherein the mounting groove (26) is located above the cooling ring groove (21), and the sealing ring (25) is arranged in the mounting groove (26), and the outer ring of the sealing ring (25) abuts against the through hole of the cylinder head (100).

3. The pre-combustion chamber assembly according to claim 1, characterized in that: The pre-combustion chamber assembly further comprises a pressing sleeve (3), the cylinder head (100) is provided with a connecting hole (101), the pressing sleeve (3) is arranged in the connecting hole (101), and the pressing sleeve (3) is pressed tightly against the pre-combustion chamber body (22).

4. The pre-combustion chamber assembly according to claim 3, characterized in that: The outer peripheral surface of the pressing sleeve (3) is provided with an external thread, the hole wall of the connecting hole (101) is provided with an internal thread, and the pressing sleeve (3) is threadedly connected to the connecting hole (101).

5. The pre-combustion chamber assembly according to claim 3, characterized in that: The diameter of the connecting hole (101) is not larger than the diameter of the mounting hole (12), and the width of the press-fitting surface between the pressing sleeve (3) and the pre-combustion chamber body (22) is larger than 1.5 mm.

6. Pre-combustion chamber cooling system, characterized in that, The pre-combustion chamber assembly comprises a thermostat, a water temperature sensor and any one of claims 1 to 5, wherein the water temperature sensor is connected to the cooling water jacket (1) by signal, and the cooling water jacket (1) is connected to the thermostat by signal.

7. The pre-combustion chamber cooling system according to claim 6, characterized in that: The pre-combustion chamber cooling system further comprises a water pump, the water pump being connected to the cooling water jacket (1), and the water pump being connected to the thermostat and the water temperature sensor signal.

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