Engine directed scavenging intake valve

Abstract

The utility model provides a kind of engine guiding scavenging intake valve, solve the problem that traditional overhead valve type engine intake valve is difficult to efficiently clean exhaust gas under two-stroke working mode to extend into engine combustion chamber, technical scheme is: the engine guiding scavenging intake valve body includes intake valve stem with intake valve head, technical key point is: intake valve stem has the gas guide pipe that is equipped with bracket and moves with intake valve stem, gas guide pipe is close to intake valve head, gas guide plate for guiding scavenging is set between gas guide pipe and intake valve head, gas guide outlet is set between gas guide pipe and gas guide plate.It can be applicable to two-stroke working engine, improve combustion efficiency and emission performance by air intake guiding scavenging, greatly improve the scavenging efficiency, and then improve engine working efficiency.

Description

Technical Field

[0001] This utility model relates to the field of internal combustion engine technology, and in particular to an engine-guided scavenging intake valve, which is suitable for the valve train mechanism of an overhead valve type two-stroke engine. Background Technology

[0002] Internal combustion engines have a history of over 150 years since their practical application. Based on their working cycle, they are mainly divided into two-stroke engines and four-stroke engines. Traditional two-stroke engines use side-mounted valves for intake and exhaust, with one revolution of the crankshaft completing one power stroke. The piston completes the four processes of intake, compression, power, and exhaust through two strokes. The exhaust gas is pushed out by a fresh air-fuel mixture. Due to limitations in its structure, valve train, and scavenging process, there is a lot of residual exhaust gas, and unburned oil is discharged with the exhaust, resulting in low combustion efficiency, poor emissions, severe exhaust pollution, and high fuel consumption. The intake valve is a crucial component of the engine's valve train. Four-stroke engines typically use an overhead valve train, including a valve assembly and valve train located in the cylinder block and cylinder head. The valve assembly includes intake and exhaust valves. The intake valve mainly consists of the valve stem and valve head, while the valve train mainly includes a cam mechanism and valve springs for driving the valve extension and retraction. A four-stroke engine operates by rotating the crankshaft twice to complete one power stroke. The piston completes the four processes of intake, compression, power, and exhaust through four strokes. While it addresses exhaust emissions through separate lubrication, its operating method has significant drawbacks. The crankshaft needs to rotate twice to complete one power stroke, and the valve train must coordinate with the crankshaft to complete all four processes. This results in substantial stroke losses and unnecessary mechanical wear, consuming additional energy and time, leading to fuel waste and mechanical damage. Furthermore, the long power stroke cycle results in a large engine size and increased manufacturing costs. Therefore, there is an urgent need to develop new engine structures and valve designs to solve these technical problems.

[0003] Patent document CN107420195B discloses a two-stroke engine based on a four-stroke engine structure. Its improved valve train structure features a longitudinally positioned intake manifold and a streamlined intake valve head. The valve seat ring within the intake manifold has a narrow throat, and the intake valve head seals the area below the valve seat ring. During operation, the transmission ratio between the crankshaft and the intake / exhaust camshafts is 1:1. Each reciprocating motion of the piston within the cylinder drives the crankshaft-connecting rod mechanism to rotate one revolution, which in turn drives the intake and exhaust valves to open once each via the camshaft transmission mechanism, forming a two-stroke working cycle. When the intake valve opens, the exhaust valve also opens. Fresh gas enters the cylinder combustion chamber through the gap between the narrow throat of the intake manifold and the intake valve head. The streamlined surface of the intake valve head guides the airflow to complete the scavenging process, increasing the effect of expelling exhaust gases after combustion in the cylinder. The intake valve remains within the intake manifold at all times. Compared to traditional disc-shaped valve heads, it enhances the airflow guidance effect. However, its intake valve head is still located at the intake manifold opening. Moreover, due to the narrow throat of the intake manifold, it greatly hinders the entry of fresh gas, reduces gas flow, and severely limits the guiding gas function. In particular, it cannot extend into the piston cylinder and deeper areas to guide gas and scavenge exhaust gases. Therefore, this intake valve cannot efficiently scavenge exhaust gases simultaneously during the intake process after extending into the engine combustion chamber, and cannot further improve combustion efficiency and emission performance. Utility Model Content

[0004] The purpose of this invention is to provide an engine-guided scavenging intake valve, which solves the problem that traditional overhead valves in engines are difficult to efficiently scavenge exhaust gases when they extend into the engine combustion chamber during a two-stroke operation. By guiding the intake air scavenging, it discharges exhaust gases, improving combustion efficiency and emission performance.

[0005] The technical solution adopted by this utility model is as follows: the engine guide scavenging intake valve includes an intake valve body disposed in the intake channel of the engine top valve distribution mechanism. The intake valve body includes an intake valve stem with an intake valve head. The key technical point is that the intake valve stem has an air guide pipe that moves with the intake valve stem through a bracket. The air guide pipe is close to the intake valve head. An air guide plate for guiding scavenging is disposed between the air guide pipe and the intake valve head. An air guide outlet is disposed between the air guide pipe and the air guide plate.

[0006] The support for the air duct is a connecting rod or connecting rib plate installed between the inner wall of the air duct and the intake valve stem.

[0007] The air guide plate is an elliptical thin plate that is obliquely fixed to the intake valve stem. The sloping surface of the elliptical thin plate and the front end of the air guide pipe form an air outlet.

[0008] The air guide plate is a sloping front end plate of the air guide pipe, and an air guide outlet is provided on the side wall of the air guide pipe near the valve head of the front end plate.

[0009] The air guide plate is a flared thin plate fixed to the intake valve stem, and the outer slope of the flared thin plate forms an air outlet with the front end of the air guide pipe.

[0010] The air guide plate is a conical air guide plate that is integrally fixed to the back of the valve head. The sloping surface of the conical air guide plate and the front end of the air guide pipe form an air guide outlet.

[0011] The advantages and beneficial effects of this utility model are: because the engine guide scavenging intake valve adopts an air guide pipe that moves with the intake valve stem in the intake valve stem fixing assembly, the air guide pipe is close to the intake valve head. Therefore, when used in the valve train of an engine with overhead valves, the increased length of the intake cam lobe can be used to push the intake valve head into the engine combustion chamber. The intake cam's operation controls the intake valve guide pipe's extension into the combustion chamber's guide area, allowing fresh air entering the cylinder to be directed into this area. Furthermore, a guide plate is placed between the guide pipe and the intake valve head for scavenging, with a guide outlet between them. This guide plate directs fresh air to scavenge exhaust gases, achieving deep scavenging of the combusted exhaust gases within the cylinder, opening the exhaust valve and thoroughly removing exhaust gases. This avoids the problem of traditional intake valves only scavenging exhaust gases at the valve opening, resulting in low scavenging efficiency. Therefore, it is particularly suitable for two-stroke engines, forming an independent lubrication system and completing one power stroke per crankshaft rotation. By guiding the intake air for scavenging, combustion efficiency and emission performance are improved, significantly increasing scavenging efficiency and thus engine efficiency. Attached Figure Description

[0012] The present invention will be further described below with reference to the accompanying drawings.

[0013] Figure 1 This is a schematic diagram of an embodiment of the present invention installed in an overhead valve engine;

[0014] Figure 2 This is a schematic diagram of the first intake valve structure according to an embodiment of the present utility model;

[0015] Figure 3 This is a schematic diagram of a second intake valve structure according to an embodiment of the present invention;

[0016] Figure 4 This is a schematic diagram of a third intake valve structure according to an embodiment of the present invention;

[0017] Figure 5 This is a schematic diagram of the fourth intake valve structure according to an embodiment of the present utility model;

[0018] Figure 6 This is a structural schematic diagram of the second working state of an embodiment of this utility model;

[0019] Figure 7 This is a structural schematic diagram of the third working state of an embodiment of this utility model;

[0020] Figure 8 This is a structural schematic diagram of the fourth working state of an embodiment of this utility model;

[0021] Figure 9 This is a structural schematic diagram of the fifth working state of an embodiment of this utility model;

[0022] Figure 10 This is a schematic diagram of the gas distribution phase of this utility model.

[0023] The numbers in the diagram are explained as follows: 1. Cylinder head, 2. Intake manifold, 3. Intake valve, 4. Engine combustion chamber, 5. Piston, 6. Crankshaft, 7. Crankcase, 8. Intake valve cam, 81. Protrusion, 9. Intake valve spring, 10. Intake valve mounting hole, 11. Exhaust valve cam, 12. Exhaust valve, 13. Exhaust port, 14. Fuel injector, 15. Air guide area, 16. Valve guide, 17. Intake bend, 18. Fresh air, 22. Exhaust gas, 31. Intake valve stem, 32. Air guide pipe, 33. Intake valve head, 34. Air guide outlet, 35. Bracket, 36. Elliptical thin plate, 37. Sloping front end plate, 38. Trumpet-shaped thin plate, 39. Conical air guide plate. Detailed Implementation

[0024] according to Figure 1-10 This utility model will be described in detail, and its implementation will be illustrated by examples. Figure 1 and Figure 2 As shown, an engine-guided scavenging intake valve is applied to the valve train of an overhead valve engine. Figure 2 The diagram shows an embodiment of the intake valve used in this invention. The intake valve body includes an intake valve stem with an intake valve head. An air guide pipe 32 is fixedly connected to the front of the intake valve stem 31 via a bracket 35, ensuring a stable connection between the air guide pipe and the valve stem. The bracket can be a connecting rod or a connecting rib. The connecting rib can be a longitudinally thin sheet to reduce air resistance. The bracket can be positioned near both ends or the middle of the air guide pipe for easy and stable connection to the valve stem. The air guide pipe 32 and the bracket 35 can be welded to the intake valve stem 31 or integrally connected and fixed. A certain distance is left between the front end of the air guide pipe and the intake valve head, and an air guide plate for guiding scavenging air is provided between the front end of the air guide pipe 32 and the intake valve head 33. The air guide plate between the front end of the air guide pipe 32 and the intake valve head 33 is an elliptical thin plate 36 that is obliquely fixed to the intake valve stem. The elliptical thin plate and the front end of the air guide pipe form an air guide outlet 34. The structure is simple and easy to guide gas for scavenging and blowing off exhaust gas.

[0025] Figure 3The diagram shows a second embodiment of the intake valve used in this invention, an improvement upon the first embodiment. A guide pipe 32 is fixed to the front of the intake valve stem 31 via a bracket 35, ensuring a stable connection between the guide pipe and the valve stem. The guide plate is a sloping front end plate 37 of the guide pipe. A guide outlet 34 is provided on the side wall of the guide pipe near the valve head. This outlet is integrally constructed with the guide pipe, facilitating assembly and manufacturing. Its simple structure allows for easy gas guidance, scavenging, and exhaust gas removal. In both embodiments one and two, the intake valve allows the guide plate to face the inner wall of the engine combustion chamber, away from the exhaust valve. This allows most of the gas entering the combustion chamber to be sprayed towards the inner wall and the top of the piston. The rebounding gas from the inner wall and the top of the piston effectively scavenges the combusted exhaust gas, improving exhaust gas removal efficiency. To prevent the intake valve's air guide tube from changing the direction of airflow due to rotation, the intake valve guide rod can be made into an elliptical shape, or a locating pin to prevent rotation can be made on the valve guide rod and the valve's air guide tube, or rotation can be prevented by limiting the intake guide rod hole in the cylinder head.

[0026] like Figure 4 The diagram shows a third type of intake valve according to an embodiment of this utility model. It is an improvement upon the first type of intake valve. An air guide pipe 32 is fixed to the front of the intake valve stem 31 via a bracket 35, ensuring a stable connection between the air guide pipe and the valve stem. The air guide plate is a flared thin plate 38 fixed to the intake valve stem. The outer slope of the flared thin plate and the front end of the air guide pipe form an air outlet 34, facilitating the guidance of gas to the surrounding areas within the engine combustion chamber. This design is simple and easy to use for scavenging.

[0027] like Figure 5 As shown, this is the fourth type of intake valve according to the present invention. It is an improvement on the first type of intake valve. An air guide pipe 32 is fixed to the front of the intake valve stem 31 by a bracket 35, so that the air guide pipe is stably connected to the valve stem.

[0028] The air guide plate is a conical air guide plate 39 that is fixed to the back of the valve head in one piece. The slope of the conical air guide plate and the front end of the air guide pipe form an air guide port. It is easy to guide gas to all sides in the engine combustion chamber. The structure is simple and easy to guide gas for scavenging.

[0029] Installation and usage methods and working process, such as Figure 1 and Figures 5 to 9As shown, the engine's guided scavenging intake valve is installed in the engine's valve train. The engine includes an engine block assembly, a crankshaft connecting rod mechanism, a valve train, a fuel supply system, and a lubrication system. The engine block assembly includes a cylinder block 4, a cylinder head 1, and a crankcase 7. The valve train uses overhead valves. An intake valve 3, driven by an intake valve cam 8 and an intake valve spring 9, is located on the cylinder head 1. The intake valve stem 31 of the intake valve 3 is located within the intake valve mounting hole 10, and the rear part of the intake valve stem 31 is located within the valve guide 16 above the intake valve mounting hole. The intake valve head 33 is used to close and open the intake passage at the front end of the intake valve stem 31. The crankshaft 6 of the crankshaft connecting rod mechanism drives the camshaft to rotate synchronously with the crankshaft via a timing gear, chain, or timing belt, operating in a two-stroke mode. The power stroke, exhaust, intake, and compression processes of the two-stroke diesel engine with the intake valve in Embodiment 3 are shown sequentially, along with the operating states at each stage. This utility model engine is a two-stroke engine, and its valve train operates differently from that of traditional engines. In a traditional four-stroke engine, the intake and exhaust valves open and close only once every two crankshaft revolutions, while in this engine, the intake and exhaust valves each open and close once per crankshaft revolution.

[0030] The work process includes the following steps: Figure 1 In the initial working state, that is, at the beginning of the power stroke, both intake valve 3 and exhaust valve 12 are closed, piston 5 is close to the top dead center position, and the protrusions of intake valve cam 8 and exhaust valve cam 10 rotate away from the valve springs. Then, the crankshaft drives the camshaft to rotate counterclockwise synchronously through the timing gear, chain, or timing belt. During the cycle, this process is also the power stroke, pushing the piston down from the top dead center, and intake valve cam 8, exhaust valve cam 11, and crankshaft 6 rotate counterclockwise. At this time, intake valve head 33 closes the intake manifold outlet, and air duct 32 closes the intake bend.

[0031] like Figure 6 As shown, the exhaust valve cam 11 is set to push the exhaust valve spring to open the exhaust valve 12 before the piston 5 moves to the bottom dead center, releasing the pressure in the engine combustion chamber. At this time, the intake valve remains closed, and the air guide pipe 32 still closes the intake bend; this allows the exhaust gas 22 after combustion to be discharged from the exhaust port 13.

[0032] like Figure 7 As shown, during the process of the intake valve moving towards the engine combustion chamber, the piston 5 continues to move to the point before the bottom dead center. The intake valve cam 8 rotates to the open intake valve state. At this time, the intake valve head 33 disengages from the intake bend outlet. The intake valve has just opened, and the air guide pipe 32 still passes through the closed intake bend. The intake passage 2 is not connected to avoid wasting compressed intake air volume.

[0033] like Figure 8As shown, the process of intake and exhaust occurs simultaneously. The piston 5 continues to move to the bottom dead center and then gradually moves upward after passing the bottom dead center. During this process, the intake valve cam 8 pushes the intake valve head 33 into the engine combustion chamber. The air guide pipe 32 gradually passes through the intake bend, making the intake bend fully open and connecting the intake passage. The intake valve reaches its maximum opening depth, allowing the intake duct to extend into the engine combustion chamber. The fresh air 18 entering the engine combustion chamber can be guided and blown into the air guide area 15 through the air guide pipe, achieving the purpose of sweeping exhaust gas deep into the engine combustion chamber. The pressurized fresh air is sent to the bottom of the engine combustion chamber, and the burned exhaust gas is discharged outside the engine combustion chamber. After reaching the maximum depth, it retracts upward, so that the movement of the intake valve head does not interfere with or collide with the movement of the piston.

[0034] like Figure 9 As shown, this illustrates the compression process of the engine piston. After scavenging, the exhaust valve 12 closes prematurely, the intake valve 3's guide pipe gradually retracts, and the guide pipe 32 moves through and closes the intake bend inlet, thus closing the intake valve. Alternatively, the exhaust and intake valves can be closed simultaneously. This position coincides with the end of the piston's fresh air exchange, the closing position of both the intake and exhaust valves, and the beginning of the compression stroke. The piston 7 then continues to move upwards to continue the air compression process. The piston continues to move upwards until it reaches top dead center, completing the compression stroke.

[0035] like Figure 1 As shown, after completing the compression stroke, the engine reaches its initial working position. Then, the air-fuel mixture is ignited, pushing the piston to perform work. The piston is near top dead center, and the fuel injector 14 operates, injecting atomized diesel fuel into the combustion chamber. Alternatively, gasoline or other combustible gases can be injected into the engine cylinder after the intake and exhaust valves are closed. Adding a spark plug transforms it into a gasoline engine. Alternatively, the engine can burn natural gas or liquefied petroleum gas (LPG). After completing one working cycle, the engine enters the next power stroke.

[0036] Figure 10 The diagram shows the valve timing of this invention. The crankshaft, intake camshaft, and exhaust camshaft rotate counter-clockwise along the coordinate axis. 'a' represents the angular range of the exhaust camshaft from opening to closing, 'b' represents the angular range of the intake camshaft from opening to closing, 'c' represents the angular range of the piston crankshaft's power stroke, and 'd' represents the angular range of the piston crankshaft's compression stroke. The intake valve can open at a position of 28 to 35 degrees before the piston reaches bottom dead center, and the exhaust valve can open at a position of 30 to 60 degrees before the intake valve opens. The intake and exhaust valves can close simultaneously or with a delay. The angle range of the protrusions on the intake and exhaust valve cams can be adjusted, reducing the engine's intake and exhaust strokes.

[0037] This invention, applied to engines, connects the intake manifold when the air guide pipe enters the engine combustion chamber at a set position, avoiding wasted compressed air intake. Compressed air is then ejected from the air guide outlet extending into the combustion chamber for efficient scavenging, and the exhaust gas is pushed out by the combustion chamber. This ensures the engine crankshaft performs work once per revolution. Therefore, manufacturing costs are reduced, engine power is increased, and the engine achieves power output comparable to large-displacement, multi-cylinder engines with a smaller displacement and number of cylinders. It also reduces fuel consumption and maintenance costs. The engine size and weight are reduced, lowering production and maintenance costs, while also reducing the size of the engine support frame. Because independent intake and exhaust strokes are eliminated, fuel efficiency is improved. Engine stroke losses are significantly reduced, minimizing fuel consumption and mechanical wear caused by intake and compression strokes, resulting in higher thermal efficiency and greater energy savings and environmental friendliness. This invention is particularly suitable for automotive engines with long pistons.

[0038] In summary, the purpose of this utility model has been achieved.

Claims

1. An engine guided scavenge intake valve comprising an intake valve body disposed in an engine overhead valve train intake port, the intake valve body comprising an intake valve stem with an intake valve head, characterized by: The intake valve stem has an air guide tube that moves with the intake valve stem via a bracket. The air guide tube is close to the intake valve head. An air guide plate for guiding scavenging air is provided between the air guide tube and the intake valve head. An air guide outlet is provided between the air guide tube and the air guide plate.

2. The engine guided scavenging intake valve of claim 1, wherein: The support for the air duct is a connecting rod or connecting rib plate installed between the inner wall of the air duct and the intake valve stem.

3. The engine guided scavenging intake valve according to claim 1 or 2, characterized in that: The air guide plate is an elliptical thin plate that is obliquely fixed to the intake valve stem. The sloping surface of the elliptical thin plate and the front end of the air guide pipe form an air outlet.

4. The engine guided scavenging intake valve according to claim 1 or 2, characterized in that: The air guide plate is a sloping front end plate of the air guide pipe, and an air guide outlet is provided on the side wall of the air guide pipe near the valve head of the front end plate.

5. The engine guided scavenging intake valve according to claim 1 or 2, characterized in that: The air guide plate is a flared thin plate fixed to the intake valve stem, and the outer slope of the flared thin plate forms an air outlet with the front end of the air guide pipe.

6. The engine guided scavenging intake valve according to claim 1 or 2, characterized in that: The air guide plate is a conical air guide plate that is integrally fixed to the back of the valve head. The sloping surface of the conical air guide plate and the front end of the air guide pipe form an air guide outlet.

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