A pre-chamber device and an engine for increasing the oxygen content of the air-fuel mixture

Abstract

The present invention belongs to the technical field of automotive engines, and particularly relates to a pre-chamber device and an engine for increasing the oxygen content of the air-fuel mixture, including a cylinder head, an exhaust valve, an exhaust valve guide, and a pre-chamber body. A pre-chamber mounting hole for mounting the pre-chamber body is provided on the cylinder head. A connection channel is provided between the exhaust valve guide and the stem of the exhaust valve. A cylinder head scavenging channel is also provided on the cylinder head. A pre-chamber scavenging channel communicating the inlet of the cylinder head scavenging channel with the inner cavity of the pre-chamber is provided on the pre-chamber body. The connection channel communicates the outlet of the cylinder head scavenging channel and the exhaust passage when the exhaust valve is opened. The pre-chamber device for increasing the oxygen content of the air-fuel mixture in this application increases the oxygen content of the air-fuel mixture in the inner cavity of the pre-chamber, can effectively improve the ignition stability and ignition performance of the pre-chamber, and effectively improves the thermal efficiency of the engine. At the same time, the structure of the present invention is simple, small in size, convenient to operate, and does not require additional components.

Description

Technical Field

[0001] The present invention belongs to the technical field of automotive engines, and particularly relates to a pre-chamber device and an engine for increasing the oxygen content of the air-fuel mixture. Background Art

[0002] With the increasingly stringent fuel consumption regulations, improving the thermal efficiency of the engine has become the main research direction. Accelerating the combustion speed, increasing the isochoric degree, reducing heat dissipation loss, and suppressing knocking are effective means to improve the thermal efficiency of the engine. Pre-chamber jet ignition can increase the combustion speed, suppress knocking, and expand the lean burn limit, and has certain potential in improving the thermal efficiency of gasoline engines. Pre-chamber jet ignition first ignites the air-fuel mixture in the pre-chamber cavity, and the high-temperature and high-pressure air-fuel mixture sprays into the main combustion chamber through small holes, forming a high-speed jet flame, which greatly increases the ignition area and improves the combustion speed. On the other hand, the unburned intermediate products in the pre-chamber can also accelerate the combustion process.

[0003] During the exhaust stroke of the engine, the exhaust gas after combustion in the main combustion chamber is discharged through the exhaust passage, but due to the influence of the pre-chamber structure, only part of the exhaust gas after combustion in the pre-chamber is discharged. During the intake stroke of the engine, fresh air or a mixture of gases enters the main combustion chamber through the intake passage, and at the same time, part of the exhaust gas remaining in the pre-chamber also enters the main combustion chamber. During the compression stroke of the engine, part of the fresh air-fuel mixture in the main combustion chamber will be pressed into the pre-chamber. Near the top dead center of compression, the residual gas coefficient in the pre-chamber is mainly affected by the amount of exhaust gas remaining in the pre-chamber after the intake stroke and the amount of fresh air-fuel mixture entering the pre-chamber during the compression stroke.

[0004] Due to the small diameter of the spray holes between the pre-chamber and the main combustion chamber, the residual exhaust gas after ignition in the pre-chamber cannot be completely discharged into the main combustion chamber during the exhaust stroke and the intake stroke of the next combustion, resulting in a large residual gas coefficient in the pre-chamber. At part load of the engine, the large residual gas coefficient leads to unstable ignition and combustion in the pre-chamber, and even misfire, resulting in poor combustion stability in the main combustion chamber. Summary of the Invention

[0005] The technical problem to be solved by the present invention is: aiming at the problem in the prior art that the residual gas coefficient in the pre-chamber is large, resulting in unstable ignition and combustion in the pre-chamber, and then poor combustion stability in the main combustion chamber, a pre-chamber device and an engine for increasing the oxygen content of the air-fuel mixture are provided.

[0006] To solve the above technical problem, an embodiment of the present invention provides a pre-chamber device for increasing the oxygen content of the air-fuel mixture, including a cylinder head, an exhaust valve, an exhaust valve guide, and a pre-chamber body. A pre-chamber installation hole for installing the pre-chamber body is provided on the cylinder head. A pre-chamber cavity is formed inside the pre-chamber body, and a pre-chamber injection hole for communicating the pre-chamber cavity with the main combustion chamber of the engine is provided at the bottom of the pre-chamber body;

[0007] An exhaust passage and an exhaust valve guide installation hole are provided on the cylinder head. The outer end of the exhaust passage is communicated with an exhaust pipe, the inner end of the exhaust passage is communicated with the main combustion chamber of the engine, the exhaust valve guide is installed in the exhaust valve guide installation hole, and the exhaust valve is slidably inserted into the exhaust valve guide; a connecting passage is provided between the exhaust valve guide and the rod body of the exhaust valve, and a cylinder head scavenging passage is further provided on the cylinder head; a prechamber scavenging passage communicating the inlet of the cylinder head scavenging passage with the inner cavity of the prechamber is provided on the prechamber body;

[0008] When the exhaust valve is opened, the connecting passage communicates the outlet of the cylinder head scavenging passage and the exhaust passage.

[0009] Optionally, when the exhaust valve is closed, the connecting passage is blocked from the outlet of the cylinder head scavenging passage and the exhaust passage.

[0010] Optionally, an exhaust ring groove and a gas guiding ring groove are provided on the exhaust valve guide. The exhaust ring groove is located below the gas guiding ring groove. The gas guiding ring groove is communicated with the outlet of the cylinder head scavenging passage, the exhaust ring groove is communicated with the exhaust passage, an exhaust valve stem ring groove is provided on the outer periphery of the rod body of the exhaust valve, the length of the exhaust valve stem ring groove is greater than the distance between the exhaust ring groove and the gas guiding ring groove, and the gas guiding ring groove, the exhaust valve stem ring groove and the exhaust ring groove form the connecting passage;

[0011] When the exhaust valve is opened, the valve stem ring groove on the exhaust valve communicates the gas guiding ring groove and the exhaust ring groove.

[0012] Optionally, when the exhaust valve is closed, the exhaust ring groove and the gas guiding ring groove are blocked by the rod body of the exhaust valve.

[0013] Optionally, a prechamber installation hole ring groove is provided around the prechamber body on the cylinder head. The prechamber installation hole ring groove is communicated with the inlet of the cylinder head scavenging passage. A plurality of prechamber scavenging passages are provided around the prechamber body. The outlets of the plurality of prechamber scavenging passages are communicated with the prechamber installation hole ring groove, and the inlets of the plurality of prechamber scavenging passages are communicated with the inner cavity of the prechamber.

[0014] Optionally, a plurality of prechamber injection holes are provided around the bottom of the prechamber body.

[0015] Optionally, the prechamber device for increasing the oxygen content of the air-fuel mixture further includes an intake valve and an intake valve guide. An intake passage and an intake valve guide installation hole are further provided on the cylinder head. The inner end of the intake passage is communicated with the main combustion chamber of the engine, the outer end of the intake passage is communicated with an intake pipe, the intake valve guide is installed in the intake valve guide installation hole, and the intake valve is slidably inserted into the intake valve guide.

[0016] Optionally, the pre-combustion chamber mounting hole is located between the intake valve and the exhaust valve and directly above the main combustion chamber of the engine;

[0017] The upper end of the pre-combustion chamber body is provided with a pre-combustion chamber injector and a pre-combustion chamber spark plug.

[0018] Optionally, the pre-combustion chamber mounting hole is a stepped circular hole, the pre-combustion chamber body is a stepped circular tube, the outer peripheral surface of the stepped circular tube matches the shape of the stepped circular hole, and the pre-combustion chamber body is press-fitted into the pre-combustion chamber mounting hole.

[0019] In the pre-combustion chamber device for increasing the oxygen content of the air-fuel mixture according to an embodiment of the present invention, a connection channel is provided between the exhaust valve guide and the rod body of the exhaust valve, and a cylinder head scavenging channel is further provided on the cylinder head; a pre-combustion chamber scavenging channel communicating the inlet of the cylinder head scavenging channel with the inner cavity of the pre-combustion chamber is provided on the pre-combustion chamber body; the connection channel communicates the outlet of the cylinder head scavenging channel and the exhaust passage when the exhaust valve is opened. The pre-combustion chamber device for increasing the oxygen content of the air-fuel mixture of the present application increases the oxygen content of the air-fuel mixture in the inner cavity of the pre-combustion chamber, can effectively improve the ignition stability and ignition performance of the pre-combustion chamber, and effectively improves the thermal efficiency of the engine. At the same time, the structure of the present invention is simple, small in size, convenient to operate, and does not require additional components.

[0020] On the other hand, an embodiment of the present invention further provides an engine, which includes a cylinder block, a piston, an injector, and the above-mentioned pre-combustion chamber device for increasing the oxygen content of the air-fuel mixture. The cylinder head is fixed on the cylinder block. A cylinder is provided on the cylinder block, the piston is slidably disposed in the cylinder, a main combustion chamber is formed between the top surface of the piston and the bottom of the pre-combustion chamber body, and the injector is installed on the cylinder head for injecting fuel into the main combustion chamber or the intake passage on the cylinder head. Description of the Drawings

[0021] Figure 1 is a schematic diagram of a pre-combustion chamber device for increasing the oxygen content of the air-fuel mixture provided by an embodiment of the present invention;

[0022] Figure 2 is another schematic diagram of a pre-combustion chamber device for increasing the oxygen content of the air-fuel mixture provided by an embodiment of the present invention.

[0023] The reference numerals in the specification are as follows:

[0024] 1. Cylinder block; 2. Piston; 3. Cylinder head; 4. Intake valve; 5. Exhaust valve; 6. Pre-combustion chamber body;

[0025] 7. Fuel injector; 8. Main combustion chamber; 30. Intake passage; 31. Exhaust passage; 32. Cylinder head scavenging passage; 33. Pre-chamber mounting hole; 34. Pre-chamber mounting hole annular groove; 40. Intake valve guide; 50. Exhaust valve guide; 51. Valve stem annular groove; 52. Exhaust annular groove; 53. Gas guiding annular groove; 60. Pre-chamber inner cavity; 61. Pre-chamber fuel injector; 62. Pre-chamber spark plug; 63. Pre-chamber injection hole; 64. Pre-chamber scavenging passage. Detailed implementation manners

[0026] In order to make the technical problems, technical solutions and beneficial effects solved by the present invention clearer and more understandable, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0027] As Figure 1-2 shown, the pre-chamber device for improving the oxygen content of the air-fuel mixture provided by the embodiment of the present invention includes a cylinder head 3, an exhaust valve 5, an exhaust valve guide 50 and a pre-chamber body 6. A pre-chamber mounting hole 33 for mounting the pre-chamber body 6 is provided on the cylinder head 3. A pre-chamber inner cavity 60 is formed inside the pre-chamber body 6. A pre-chamber injection hole 63 communicating the pre-chamber inner cavity 60 with the main combustion chamber 8 of the engine is provided at the bottom of the pre-chamber body 6.

[0028] An exhaust passage 31 and an exhaust valve guide 50 mounting hole are provided on the cylinder head 3. The outer end of the exhaust passage 31 is communicated with an exhaust pipe (not shown in the figure), and the inner end of the exhaust passage 31 is communicated with the main combustion chamber 8 of the engine. The exhaust valve guide 50 is installed in the exhaust valve guide 50 mounting hole, and the exhaust valve 5 is slidably inserted into the exhaust valve guide 50. A connection passage is provided between the exhaust valve guide 50 and the rod body of the exhaust valve 5. A cylinder head scavenging passage 32 is also provided on the cylinder head 3. A pre-chamber scavenging passage 64 communicating the inlet of the cylinder head scavenging passage 32 with the pre-chamber inner cavity 60 is provided on the pre-chamber body 6.

[0029] The connection passage communicates the outlet of the cylinder head scavenging passage 32 and the exhaust passage 31 when the exhaust valve 5 is opened.

[0030] In one embodiment, the connection passage is blocked from the outlet of the cylinder head scavenging passage 32 and the exhaust passage 31 when the exhaust valve 5 is closed.

[0031] In one embodiment, an exhaust ring groove 52 and an air guiding ring groove 53 are provided on the exhaust valve guide 50. The exhaust ring groove 52 is located below the air guiding ring groove 53. The air guiding ring groove 53 is communicated with the outlet of the cylinder head scavenging passage 32, and the exhaust ring groove 52 is communicated with the exhaust passage 31. An exhaust valve stem ring groove 51 is provided on the outer periphery of the stem of the exhaust valve 5. The length of the exhaust valve stem ring groove 51 is greater than the distance between the exhaust ring groove 52 and the air guiding ring groove 53. The air guiding ring groove 53, the exhaust valve stem ring groove 51 and the exhaust ring groove 52 form the connection passage.

[0032] When the exhaust valve 5 is opened, the valve stem ring groove 51 on the exhaust valve 5 communicates the air guiding ring groove 53 and the exhaust ring groove 52. In one embodiment, when the exhaust valve 5 is closed, the exhaust ring groove 52 and the air guiding ring groove 53 are blocked by the stem of the exhaust valve 5.

[0033] In one embodiment, a prechamber mounting hole ring groove 34 is provided on the cylinder head 3 around the prechamber body 6. The prechamber mounting hole ring groove 34 is communicated with the inlet of the cylinder head scavenging passage 32. A plurality of prechamber scavenging passages 64 are provided around the prechamber body 6. The outlets of the plurality of prechamber scavenging passages 64 are communicated with the prechamber mounting hole ring groove 34, and the inlets of the plurality of prechamber scavenging passages 64 are communicated with the prechamber inner cavity 60.

[0034] In one embodiment, a plurality of prechamber injection holes 63 are provided around the bottom of the prechamber body 6.

[0035] In one embodiment, the prechamber device for increasing the oxygen content of the air-fuel mixture further includes an intake valve 4 and an intake valve guide 40. An intake passage 30 and an intake valve guide 40 mounting hole are further provided on the cylinder head 3. The inner end of the intake passage 30 is communicated with the main combustion chamber 8 of the engine, and the outer end of the intake passage 30 is communicated with an intake pipe (not shown in the figure). The intake valve guide 40 is installed in the intake valve guide 40 mounting hole, and the intake valve 4 is slidably inserted into the intake valve guide 40.

[0036] In one embodiment, the prechamber mounting hole 33 is located between the intake valve 4 and the exhaust valve 5 and directly above the main combustion chamber 8 of the engine.

[0037] The upper end of the prechamber body 6 is provided with a prechamber injector 61 injector 7 and a prechamber spark plug 62.

[0038] In one embodiment, the prechamber mounting hole 33 is a stepped round hole, and the prechamber body 6 is a stepped round tube. The outer peripheral surface of the stepped round tube matches the shape of the stepped round hole, and the prechamber body 6 is press-fitted into the prechamber mounting hole 33.

[0039] The working principle of the embodiment of the present invention is as follows: During the intake stroke, the intake valve 4 opens, the exhaust valve 5 closes, the piston 2 moves downward, and air enters the main combustion chamber 8 from the intake passage 30 through the intake valve 4. The fuel injector 7 can inject fuel into the intake passage 30 or the main combustion chamber 8. Part of the exhaust gas remaining in the pre-combustion chamber cavity 60 in the previous cycle may flow out through the pre-combustion chamber injection holes into the main combustion chamber 8 under the action of the pressure difference.

[0040] During the compression stroke, both the intake valve 4 and the exhaust valve 5 are closed, the piston 2 moves upward, and the mixture in the cylinder is compressed. The oil-gas mixture in the main combustion chamber 8 is pressed into the pre-combustion chamber cavity 60. The pre-combustion chamber injector 61 on the pre-combustion chamber body 6 injects a small amount of fuel into the pre-combustion chamber cavity 60 to form an ignitable mixture in the pre-combustion chamber cavity 60.

[0041] At the end of the compression stroke, when the piston 2 is about to reach the top dead center, the pre-combustion chamber spark plug 62 on the pre-combustion chamber body 6 ignites the oil-gas mixture in the pre-combustion chamber cavity 60. At this time, the exhaust valve 5 is in the closed state, and the exhaust ring groove 52 and the air guide ring groove 53 are blocked by the rod body of the exhaust valve 5. The combustible mixture reacts and releases heat in the pre-combustion chamber cavity 60, the pressure and temperature in the cavity rise, and in addition, the exhaust ring groove 52 and the air guide ring groove 53 are disconnected, and the high-temperature mixture can only be sprayed into the main combustion chamber 8 through the pre-combustion chamber injection holes 63 and ignite the mixture around the main combustion chamber 8.

[0042] During the power stroke, the mixture in the main combustion chamber 8 is ignited by the high-temperature gas ejected from the pre-combustion chamber injection holes 63, burns rapidly, and the pressure and temperature increase rapidly, pushing the piston 2 to move downward.

[0043] During the exhaust stroke, the exhaust valve 5 opens and the piston 2 moves upward. One flow path of the exhaust gas after combustion in the main combustion chamber 8 is from the main combustion chamber 8 through the exhaust valve 5 into the exhaust passage 31. At this time, the exhaust valve 5 is open, and the exhaust ring groove 52 and the air guide ring groove 53 are in communication. Another flow path of the exhaust gas after combustion in the main combustion chamber 8 is through the pre-combustion chamber injection holes 63, the pre-combustion chamber scavenging passage 64, the pre-combustion chamber mounting hole ring groove 34, the cylinder head scavenging passage 32, the air guide ring groove 53, the valve stem ring groove 51 and the exhaust ring groove 52, and finally into the exhaust passage 31. In this way, the exhaust gas with a high oxygen content in the main combustion chamber 8 enters the pre-combustion chamber cavity 60, and the exhaust gas with a very low oxygen content in the original cavity is squeezed out through the holes of the pre-combustion chamber scavenging passage 64 into the exhaust passage 31.

[0044] Then the above steps are repeated.

[0045] The prechamber device for increasing the oxygen content of the air-fuel mixture provided by the embodiment of the present invention is provided with a connection channel between the exhaust valve guide and the rod body of the exhaust valve, and a cylinder head scavenging channel is further provided on the cylinder head; a prechamber scavenging channel communicating the inlet of the cylinder head scavenging channel with the inner cavity of the prechamber is provided on the prechamber body; the connection channel communicates the outlet of the cylinder head scavenging channel and the exhaust passage when the exhaust valve is opened. The prechamber device for increasing the oxygen content of the air-fuel mixture of the present application increases the oxygen content of the air-fuel mixture in the inner cavity of the prechamber, can effectively improve the ignition stability and ignition performance of the prechamber, and effectively improves the thermal efficiency of the engine. At the same time, the structure of the present invention is simple, small in size, convenient to operate, and does not require additional components.

[0046] In addition, an embodiment of the present invention further provides an engine, which includes a cylinder block 11, a piston 2, an injector 7, and the above-mentioned prechamber device for increasing the oxygen content of the air-fuel mixture. The cylinder head is fixed on the cylinder block 1. A cylinder is provided on the cylinder block 1. The piston 2 is slidably arranged in the cylinder. A main combustion chamber 8 is formed between the top surface of the piston 2 and the bottom of the prechamber body 6. The injector 7 is installed on the cylinder head 3 and is used for injecting fuel into the main combustion chamber 8 or the intake passage on the cylinder head 3.

[0047] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A prechamber device for increasing the oxygen content in the mixture gas, characterized in that, It includes a cylinder head, an exhaust valve, an exhaust valve guide, and a prechamber body. A prechamber installation hole for installing the prechamber body is provided on the cylinder head. A prechamber inner cavity is formed inside the prechamber body. A prechamber injection hole communicating the prechamber inner cavity with the main combustion chamber of the engine is provided at the bottom of the prechamber body; An exhaust passage and an exhaust valve guide installation hole are provided on the cylinder head. The outer end of the exhaust passage is communicated with an exhaust pipe, the inner end of the exhaust passage is communicated with the main combustion chamber of the engine, the exhaust valve guide is installed in the exhaust valve guide installation hole, and the exhaust valve is slidably inserted into the exhaust valve guide; A connection passage is provided between the exhaust valve guide and the rod body of the exhaust valve. A cylinder head scavenging passage is also provided on the cylinder head; A prechamber scavenging passage communicating the inlet of the cylinder head scavenging passage with the prechamber inner cavity is provided on the prechamber body; When the exhaust valve is opened, the connection passage communicates the outlet of the cylinder head scavenging passage and the exhaust passage. When the exhaust valve is closed, the connection passage is blocked from the outlet of the cylinder head scavenging passage and the exhaust passage; An exhaust ring groove and a gas guiding ring groove are provided on the exhaust valve guide. The exhaust ring groove is located below the gas guiding ring groove. The gas guiding ring groove is communicated with the outlet of the cylinder head scavenging passage. The exhaust ring groove is communicated with the exhaust passage. An exhaust valve rod ring groove is provided on the outer periphery of the rod body of the exhaust valve. The length of the exhaust valve rod ring groove is greater than the distance between the exhaust ring groove and the gas guiding ring groove. The gas guiding ring groove, the exhaust valve rod ring groove, and the exhaust ring groove form the connection passage; When the exhaust valve is opened, the valve rod ring groove on the exhaust valve communicates the gas guiding ring groove and the exhaust ring groove.

2. The pre-chamber device for increasing the oxygen content in the mixture gas according to claim 1, wherein, When the exhaust valve is closed, the exhaust ring groove and the gas guiding ring groove are blocked by the rod body of the exhaust valve.

3. The pre-chamber device for increasing the oxygen content in the mixture gas according to claim 1, characterized in that, A prechamber installation hole ring groove is provided on the cylinder head surrounding the prechamber body. The prechamber installation hole ring groove is communicated with the inlet of the cylinder head scavenging passage. A plurality of prechamber scavenging passages are provided around the prechamber body. The outlets of the plurality of prechamber scavenging passages are communicated with the prechamber installation hole ring groove. The inlets of the plurality of prechamber scavenging passages are communicated with the prechamber inner cavity.

4. The pre-chamber device for increasing the oxygen content of the mixture gas according to claim 1, characterized in that, A plurality of prechamber injection holes are provided around the bottom of the prechamber body.

5. The pre-chamber device for increasing the oxygen content of the mixture gas according to claim 1, characterized in that, The prechamber device for increasing the oxygen content of the air-fuel mixture further includes an intake valve and an intake valve guide. An intake passage and an intake valve guide installation hole are also provided on the cylinder head. The inner end of the intake passage is communicated with the main combustion chamber of the engine. The outer end of the intake passage is communicated with an intake pipe. The intake valve guide is installed in the intake valve guide installation hole. The intake valve is slidably inserted into the intake valve guide.

6. The pre-chamber device for increasing the oxygen content in the mixture gas according to claim 5, characterized in that, The prechamber installation hole is located between the intake valve and the exhaust valve and directly above the main combustion chamber of the engine; A prechamber injector and a prechamber spark plug are provided at the upper end of the prechamber body.

7. The pre-chamber device for increasing the oxygen content of the mixture gas according to claim 1, characterized in that, The prechamber installation hole is a stepped round hole, and the prechamber body is a stepped round tube. The outer peripheral surface of the stepped round tube matches the shape of the stepped round hole. The prechamber body is press-fitted into the prechamber installation hole.

8. An engine, characterized in that, It includes a cylinder block, a piston, an injector, and a prechamber device for increasing the oxygen content in the air-fuel mixture according to any one of claims 1-7. The cylinder head is fixed on the cylinder block. A cylinder is provided on the cylinder block. The piston is slidably arranged in the cylinder. A main combustion chamber is formed between the top surface of the piston and the bottom of the prechamber body. The injector is installed on the cylinder head and is used to inject fuel into the main combustion chamber or the intake passage on the cylinder head.

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