Opposed piston internal combustion engine

Abstract

The invention relates to an opposed piston internal combustion engine. In the prior art, an opposed piston crank mechanism is provided, combustion gas pressure is converted into kinetic energy of two pistons, so that heat efficiency is effectively improved, but a fixed air cylinder cover cannot be formed, and the opposed piston crank mechanism cannot adapt to a traditional internal combustion engine structure. With the complexity of the internal combustion engine disclosed in the prior art, high component precision and size management are required, but not practical. Besides, in order to reduce fuel consumption, low-rotating-speed operation is effective, but in a traditional piston crank mechanism, vibration can be generated at the low rotating speed, and a balance mechanism needs to be added to cope with the vibration. In the opposed piston mechanism of the present invention, an intake compression cylinder (1) and an expansion exhaust cylinder (2) are provided, respectively, and a rotary perforated cylindrical valve (3) and an ignition combustion chamber (4) are provided between the intake compression cylinder (1) and the expansion exhaust cylinder (2). The valve mechanism is disposed on the cylinder side surface side, and operates an intake valve (33) and an exhaust valve (34) on the cylinder side surface via a movable fulcrum rocker arm (8) by means of a disc cam (7) rotationally interlocked with a crank. The opening / closing amount of the intake valve (33) and the exhaust valve (34) is also realized by the movable structure of the rocker arm according to the operation state of the internal combustion engine. The piston pin (18) and the piston pin (30) can absorb the deviation of the internal combustion engine generated when the two connecting rods are connected by one piston, so that the two connecting rods can be easily connected by one piston. In addition, the connecting rods can also be arranged oppositely like the piston, thereby counteracting unbalanced inertia and reducing vibration at low rotation speed.

Description

Technical Field

[0001] The present invention relates to an internal combustion engine using an opposed piston crank mechanism. Background Art

[0002] The opposed piston crank mechanism can convert the pressure of the combustion gas into kinetic energy using the opposed pistons. In a conventional thermal engine, the energy that escapes to the cylinder head and its components in the form of heat is recovered as kinetic energy, thereby improving thermal efficiency. However, in the opposed piston crank mechanism, the part equivalent to the cylinder head of a conventional internal combustion engine becomes the piston on the opposing side, so it is impossible to form a widely used overhead valve mechanism. In order to construct an opposed piston mechanism, it is necessary to significantly change the configuration and structure of the intake valve, exhaust valve, spark plug and fuel injector of the cylinder head in a conventional internal combustion engine.

[0003] In order to reduce fuel consumption, running the internal combustion engine at a low speed is effective because it reduces the number of combustions per unit time. However, when running at a low speed, the vibration caused by the unbalanced inertial force of the piston and connecting rod can cause discomfort during the operation of the internal combustion engine and damage to the internal combustion engine. In response to this unbalanced inertial force, people have proposed a method to offset the inertial force couple generated when the reciprocating motion is converted into rotational motion by increasing the relative pistons, cranks and connecting rods and arranging them symmetrically. However, this will increase the number of components, parts are needed to ensure symmetry, the dimensional accuracy requirements between the parts are also high, and the mechanism is also complicated.

[0004] Prior art literature

[0005] Patent Literature

[0006] Japanese Patent Publication (B2) Hei 2-25062 Summary of the invention

[0007] Problems to be solved by the invention

[0008] In conventional mechanisms, since each process of intake, compression, combustion, expansion, and exhaust is performed in the same cylinder, the valve train, spark plug, fuel injector, and other components required for each process are concentrated on the cylinder head. For opposed piston mechanisms without a cylinder head, the efficient arrangement of these devices becomes very important.

[0009] In a mechanism that symmetrically arranges the connecting rod and crank and further opposes them to achieve inertial balance, the connection position between the piston and the connecting rod may be offset due to dimensional deviations of the components of the internal combustion engine, dimensional deviations between components, gear clearance, etc. This offset may hinder the smooth movement of the piston.

[0010] Means of solving problems

[0011] The intake air compression cylinder 1 and the expansion and exhaust cylinder 2 are arranged in parallel. In addition, a rotating perforated cylindrical valve 3 and an ignition combustion chamber 4 for introducing and sealing compressed air are arranged between the intake air compression cylinder 1 and the expansion and exhaust cylinder 2. The intake air compression cylinder 1 and the ignition combustion chamber 4 have an introduction hole 27. When the rotating perforated cylindrical valve 3 is opened, the high-pressure air compressed in the intake air compression cylinder 1 is introduced into the ignition combustion chamber 4 through the introduction hole 27 and the rotating perforated cylindrical valve 3. The rotating perforated cylindrical valve 3 achieves airtightness by seamless and annular seals 5 and 6 that seal the outer periphery of the introduction hole, and annular seals 20 and 21 that are arranged in a concave shape on the cylindrical side surface of the rotating perforated cylindrical valve 3. The seals 5 and 6 are in close contact with the cylindrical side from the back under the action of the leaf spring 22 and the lubricating oil pressure. The rotary perforated cylindrical valve 3 has an annular groove 23 for fixing the annular seal 20 and the annular seal 21 in order to ensure airtightness and lubrication and cooling. The groove has a lubricating oil supply hole 24 inside, and lubricating oil is supplied to the annular seal 20 and the annular seal 21. The ignition combustion chamber 4 is provided with a fuel injection device 25 and a spark plug 26. There is a combustion gas ejection hole 44 for introducing the combustion gas generated in the combustion chamber of the ignition combustion chamber 4 into the expansion and exhaust cylinder 2. When necessary, in order to achieve multi-stage fuel injection, a multi-stage fuel injection device 28 can be provided on the expansion and exhaust cylinder 2. The combustion performed by this mechanism occurs once relative to one crank rotation, which helps to ensure output.

[0012] For the valve mechanism for intake and exhaust, a disc cam 7 having a concave-convex shape on the disc surface of a cylinder rotating synchronously with the crank is provided. The concave-convex amount has a concave-convex shape not only in the circumferential direction but also in the diameter direction. The rocker arm 8 has a contact roller 9 at the contact point with the disc cam 7, and swings according to the concave-convex shape of the disc cam 7 according to the lever principle. The rocker arm bracket 11 that fixes the rocker arm 8 includes a rocker arm pin 12 that acts as a fulcrum when the rocker arm swings, and has a gear shape that meshes with the input gear 13 that operates for adjusting intake and exhaust, and the rocker arm bracket 11 moves linearly on the guide rail 29. Through the action of the input gear 13, the contact point between the disc cam 7 and the contact roller 9 moves, and since the concave-convex amount of the disc cam in the diameter direction also changes, the swing amount of the rocker arm also changes accordingly. At the same time, since the distance between the valve contact point and the fulcrum also changes, it also has the effect of changing the valve movement amount. By operating the input gear 13, the opening and closing amount of the valve can be changed.

[0013] The piston pin is divided into two parts, the piston pin 18 and the piston pin 30, and is arranged at both ends of the pin center axis. In addition, there are two circular holes that engage with the connecting rod connecting pin 17 and the connecting rod connecting pin 32, and are connected to the two symmetrically arranged connecting rods 16 and the connecting rod 31. The connecting rod is also connected to the symmetrically arranged cranks 19 and 35. The outer circumference of the piston pin 18 and the piston pin 30 is circular and can rotate relative to the piston. In the process of transmitting power to the output shaft respectively, the two connected connecting rods have different parts in the related parts. Therefore, due to the dimensional deviation of each component and the dimensional deviation of the internal gear of the internal combustion engine, the position of the connecting rod connecting pin 17 and the connecting pin 32 will be offset. However, this offset can be absorbed by the rotation of the piston pin 18 and the piston pin 30, thereby minimizing the impact of the above-mentioned deviation.

[0014] Effects of the Invention

[0015] The rotating holed cylindrical valve 3 introduces and cuts off the compressed air by rotating, so the separation of the intake and compression cylinder 1 and the expansion and exhaust cylinder 2 can be achieved with a simple structure and a small power loss. Each cylinder can be set to the optimal volume according to the required internal combustion engine output, and the volume of the intake side and the exhaust side can be set without using a complicated mechanism or control, thereby improving the combustion efficiency. In addition, the number of combustions per crank rotation is one, so the output is improved, and the output pulsation during low-speed operation is also reduced.

[0016] The ignition combustion chamber 4 can be spherical in shape, and combustion becomes an ideal flame propagation. Reducing unburned fuel contributes to high output and exhaust gas purification. The combustion chamber is a small and simple structure, and the material of this part can be easily replaced with heat-resistant and pressure-resistant materials, corrosion-resistant materials, and high-insulation materials when necessary, so it can easily cope with high-temperature, high-pressure combustion and various fuels.

[0017] The valve mechanism of the movable fulcrum rocker arm can change the opening and closing timing of the valve and the lift of the valve according to the accelerator operation and the load of the internal combustion engine, so as to reduce fuel consumption and ensure power output when necessary. The simple and compact mechanism makes it easy to configure the valve opening and closing mechanism on the side of the cylinder, which promotes the realization of the opposed piston crank mechanism.

[0018] For an internal combustion engine with one piston and multiple connecting rods, positional deviation may occur at the connecting rod-piston connection point due to factors such as dimensional tolerances of the various components and clearances of internal gears. However, this deviation is absorbed by the rotation of piston pin 18 and piston pin 30 relative to the piston, so that the piston can move smoothly in a straight line relative to the cylinder as in a conventional internal combustion engine without being affected by the above-mentioned deviation. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1It is a schematic diagram of the configuration of the mechanism related to the present invention, in which the central axis of the cylinder is set vertically. It is a state in which the crank angle is at the top dead center of the piston, the hole of the rotating perforated cylindrical valve 3 is aligned with the intake and compression cylinder 1 and the inlet hole 27 of the ignition combustion chamber 4, and the compressed gas is introduced into the ignition combustion chamber 4.

[0020] Figure 2 The rotary hole cylindrical valve 3 is opened Figure 1 In the AA cross-sectional view, the air pressurized by the intake compression cylinder 1 is introduced into the ignition combustion chamber 4, and the black arrows indicate the flow of high-pressure air.

[0021] Figure 3 is Figure 2 In the state of the process progress, in the state of ignition and combustion Figure 1 The AA cross-sectional view in FIG. 1 shows that the rotating perforated cylindrical valve 3 is closed, the fuel injection device 25 and the spark plug 26 are working, and the ignition combustion state is in progress. The black arrow indicates the burning fuel.

[0022] Figure 4 is Figure 3 In the state where the process progresses, the intake, expansion process and multi-stage fuel injection Figure 1 In the AA cross-section diagram, the hollow arrows represent the intake air and the black arrows represent the burning fuel.

[0023] Figure 5 is Figure 4 In the state where the process progresses, the crank angle passes the piston bottom dead center and becomes the compression and exhaust process. Figure 1 The hollow arrow indicates exhaust, and then the return Figure 2 , one rotation of the crank completes one cycle.

[0024] Figure 6 This is a diagram of the structure of the rotating perforated cylindrical valve and the ignition combustion chamber. For ease of understanding, half of the center is omitted.

[0025] Figure 7 This is an exploded view of the rotating perforated cylindrical valve and the ignition combustion chamber, with half of the center omitted for ease of understanding.

[0026] Figure 8 This is a diagram showing the structure of a valve mechanism, in which the disc cam 7 and the gear 38 are integrated.

[0027] Fig. 9 It is an exploded view of the valve mechanism when the cam contact roller 9 is used.

[0028] Fig.10 It is an exploded view of the valve mechanism when the cam contact ball 14 is used.

[0029] Fig.11 It is a valve mechanism diagram when the crank angle at which the valve opening becomes larger and the cam contact roller 9 contacts the maximum bulge of the disc cam 7.

[0030] Fig.12 is relative to Fig.11 In the state, the rocker arm bracket 11 moves through the operation of the input gear 13, so that the cam contact position also moves, and the cam contact roller 9 contacts the disc cam 7 at a place where the cam protrusion of the disc cam 7 is small. Fig.11 Diagram of the valve train when the valve opening and closing amount decreases at the same crank angle.

[0031] Fig.13 This is a diagram showing the structure of the piston pin and surrounding parts.

[0032] Fig.14 This is an exploded view of the piston pin and surrounding components.

[0033] Fig.15 This is a diagram of the embodiment as seen from the exhaust valve side.

[0034] Fig.16 This is a diagram of the embodiment as seen from the intake valve side. DETAILED DESCRIPTION

[0035] The present invention can be implemented as a power using an internal combustion engine (such as a car or a generator). Specific embodiments are as follows.

[0036] Example

[0037] Fig.15 and Fig.16An embodiment is shown in FIG. In order to facilitate understanding of the structure, the crankcase and the cylinder formed by it are omitted. The intake compression cylinder and the expansion exhaust cylinder are arranged horizontally. Two intake pistons 15 are arranged opposite to each other, and two pistons 37 for the expansion exhaust process are also arranged opposite to each other, and each piston is connected to two connecting rods. There are a total of four crankshafts, which are located in symmetrical and opposite positions and are linked by gears 38 and 39. Disc cams 7 and 40 are arranged at the end of the crank, and the valve mechanism is arranged on the side of the cylinder. The input gear 13 is operated by the internal combustion engine operation control device. When the operating environment does not change, it is operated in conjunction with the accelerator operation. The vibration caused by the unbalanced inertia of the piston and connecting rod that causes vibration in the traditional internal combustion engine is offset in this embodiment due to the symmetrical configuration, so no balancer is set. The output shaft can ensure two output shafts 41 and 42, one of which can be connected to the driving shaft load or the like in operation, and the other can be connected to the generator that converts the remaining output into power. In addition, the compressor, generator and other internal combustion engine auxiliary machines that are connected by belts or chains in the traditional mechanism can be directly connected to more cranks than in the traditional mechanism in the present invention, thereby reducing the number of components and the running resistance of the internal combustion engine. Through the present invention, the internal combustion engine can achieve a compact and efficient structure.

[0038] Industrial Applicability

[0039] By efficiently burning expensive and precious carbon-neutral fuel at low speeds, fuel consumption can be reduced. In addition, vibration can be reduced even when running at low speeds, taking into account comfort. Therefore, it is possible to replace conventional internal combustion engines used in automobiles, etc., which need to reduce carbon dioxide emissions to protect the global environment, with this internal combustion engine.

[0040] Explanation of symbols

[0041] 1. Cylinder for suction and compression; 2. Cylinder for expansion and exhaust; 3. Rotary cylindrical valve with holes; 4. Ignition combustion chamber; 5. Seal; 6. Seal; 7. Disc cam; 8. Rocker arm; 9. Cam contact roller; 10. Reciprocating opening and closing valve; 11. Rocker arm bracket; 12. Rocker arm pin; 13. Input gear; 14. Cam contact ball; 15. Piston; 16. Connecting rod; 17. Connecting rod connecting pin; 18. Piston pin; 19. Crank 20. Annular seal; 21. Annular seal; 22. Leaf spring; 23. Annular groove; 24. Lubricating oil supply hole; 25. Fuel injection device; 26. Spark plug; 27. Inlet hole; 28. Multi-stage fuel injection device; 29. ​​Guide rail; 30. Piston pin; 31. Connecting rod; 32. Connecting rod connecting pin; 33. Intake valve; 34. Exhaust valve; 35. Crank; 36. Crank; 37. Piston; 38. Gear; 39. Gear; 40. Disc cam; 41. Output shaft; 42. Output shaft; 43. Crank; 44. Combustion gas ejection hole.

Claims

1. An internal combustion engine, characterized in that: In an opposed piston crank mechanism, a cylinder (1) for air intake and compression and a cylinder (2) for air expansion and exhaust are respectively arranged, and a rotating perforated cylindrical valve (3) and an ignition combustion chamber (4) are provided between them.

2. An internal combustion engine, characterized in that: A seamless annular seal (5) and a seal (6) are provided, and the seal (5) and the seal (6) seal the outer periphery of the air inlet hole of the intake and compression cylinder and the ignition and combustion chamber.

3. A valve mechanism, characterized in that: On the disk surface side of the disk that rotates in conjunction with the crank, there is a disk cam (7) whose cam concave-convex amount changes continuously in the circumferential direction and the radial direction. The rocker arm (8) pushed by the disc cam (7) is provided with a cam contact roller (9) at one end and contacts the disc cam (7), and contacts the reciprocating on-off valve (10) at the other end. The rocker arm bracket (11) fixing the rocker arm can be moved in a straight line by means of a guide rail (29), and the rocker arm bracket (11) can be moved by external input, thereby adjusting the opening and closing amount of the reciprocating opening and closing valve.

4. A valve mechanism, characterized in that: In the above valve mechanism, the cam contact roller (9) is set as a cam contact ball (14).

5. A piston pin, characterized in that: The piston pin has two circular holes and can rotate around the piston pin axis relative to the piston 15, and is divided into two piston pins (18) and a piston pin (30). The two circular holes are used to engage with a connecting pin (17) and a connecting pin (32) respectively. The connecting pin (17) and the connecting pin (32) are connected to a connecting rod (16) and a connecting rod (31) respectively between the two piston pins (18) and the piston pin (30).

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