Internal combustion engine piston and internal combustion engine using same

Abstract

A double-piston internal combustion engine, comprising a main piston (304) connected to crankshafts and an auxiliary piston (305) driven by cams (803). A piston cap (201) and a piston core (202) of the auxiliary piston (305) form a one-way valve (104), which allows air intake from left to right, and when the main piston (304) moves to a position near the right dead center, an exhaust sliding valve (601) is pushed open, and exhaust gas is discharged from an exhaust port. In the final phase of exhaust, the auxiliary piston (305) moves rightwards and is engaged with the main piston (304), and the waste gas is completely discharged, so that an exhaust stroke is completed; and fresh air is suctioned into an air inlet chamber behind the auxiliary piston (305). Then, the two pistons move leftwards, the speed of the auxiliary piston (305) is faster, and a space is formed between the auxiliary piston (305) and the main piston (304), so that a combustion chamber is formed; the fresh air passes through the one-way valve (104) on the auxiliary piston (305) and enters the combustion chamber, so that an air intake stroke is completed. The auxiliary piston (305) stops moving when reaching the left dead center thereof; in this case, the main piston (304) moves approximately to the middle, and then continues to move leftwards to the bottom, so that a compression stroke is realized. Then, gas is combusted, and the main piston (304) is pushed to the right, so that a power stroke is completed. The combusted gas continues to move to the exhaust port, so that an exhaust stroke is started.

Description

Internal combustion engine piston and internal combustion engine using the piston Technical Field

[0001] The invention belongs to the field of internal combustion engines. Background Art

[0002] Conventional internal combustion engines come in two types: four-stroke and two-stroke. Four-stroke internal combustion engines offer high ventilation quality and complete combustion, but completing the four-stroke combustion cycle requires two crankshaft rotations and two piston reciprocating cycles, resulting in low efficiency and power density. Two-stroke internal combustion engines only require one crankshaft rotation and one piston reciprocating cycle to complete the combustion cycle, offering high efficiency and power density. However, the low ventilation quality and incomplete combustion lead to high fuel consumption, oil burning, and environmental pollution. Two-stroke internal combustion engines later introduced technologies such as opposed-piston DC scavenging, but these still haven't completely overcome the drawbacks of poor ventilation quality, and are therefore not widely used. SUMMARY OF THE INVENTION

[0003] The present invention provides a 2x2 stroke internal combustion engine, which uses two pistons, each of which reciprocates once during one crankshaft rotation cycle to complete four strokes of intake, compression, power generation and exhaust, so as to achieve the effects of high efficiency, high power density, sufficient ventilation and complete combustion. Technical issues

[0004] The problem with traditional four-stroke internal combustion engines is that the four-stroke combustion cycle requires two crankshaft rotations and two piston reciprocating cycles, resulting in low efficiency and low power density. The problem with traditional two-stroke engines is that they have low ventilation quality and incomplete combustion. Technical Solutions

[0005] The object of the present invention is to provide an internal combustion engine with high ventilation quality and capable of completing a four-stroke cycle during one crankshaft rotation or one piston reciprocation, thereby achieving high efficiency, high power density, sufficient ventilation, and complete combustion.

[0006] The purpose of the present invention is achieved through a piston with a one-way valve. The cylinder head of the existing four-stroke internal combustion engine is split into two parts: a fixed intake cover and a movable intake piston, and the exhaust port is moved to the vicinity of the bottom dead center of the original piston. In this way, there are two opposing pistons in the cylinder. The original piston is called the power piston or main piston, and the newly added piston is called the ventilation piston or auxiliary piston. When the work is completed and the main piston is near the bottom dead center, the exhaust is immediately exhausted. At the same time, the ventilation piston moves downward to force the exhaust and also inhales new air from the back. The ventilation piston then quickly returns to the top, and the new air passes through the one-way valve into the combustion chamber, completing the intake. This process is equivalent to the forced direct current scavenging performed by the ventilation piston in a two-stroke internal combustion engine, and thus has the advantages of both two- and four-stroke internal combustion engines. The key point is that the ventilation piston has the ability to allow gas to pass in one direction.

[0007] In order to distinguish it from the existing four-stroke internal combustion engine and because of the convention of opposed piston internal combustion engines, the cylinder of the internal combustion engine of the present invention is placed horizontally, with the gas exchange piston on the left and the power piston on the right. This is only for the convenience of description and has no technical significance.

[0008] The basic technical solution provided by the present invention is a piston with a one-way valve, comprising a piston body (101) and a piston rod (103), wherein the side of the piston body facing the combustion chamber is the piston top surface, and the side opposite to the piston top surface is the piston back surface, and the feature is that the piston body comprises a piston valve - a non-diaphragm one-way valve (104) that allows gas to flow from the piston back side to the piston top side but not the other way around.

[0009] A one-way valve, also known as a check valve or non-return valve, is the most fundamental directional control element in the field of fluid control. However, perhaps because it is so basic and simple, its precise structural definition is difficult to find. Generally speaking, a one-way valve consists of a valve body, a monotonically variable flow channel within the body cavity, and an object that blocks the flow channel, referred to as a blocking member. Since it is a monotonically variable flow channel, it must be large at one end and small at the other. The end with the larger channel size is called the large end or large section, and the end with the smaller channel size is called the small end or small section. The blocking member is sized between the large and small ends of the flow channel; it can enter the large end of the flow channel but cannot pass through the small end. Therefore, when fluid flows from the large end to the small end, the fluid's viscosity drives the blocking member toward the small end. Ultimately, due to its large size, the blocking member becomes stuck in the flow channel, blocking the flow and closing the valve. Conversely, when the fluid flows from the small end to the large end, the plug moves away from the small end, creating a gap between the plug and the flow channel. The fluid can flow through the gap, thus opening the valve. To ensure reliable closure at low flow rates, a small force is usually added to push the plug toward the small end. Spring force is the most common, but gravity can also be used.

[0010] The shape of the flow channel can be gradual or sudden. The shape of the plug can be roughly divided into plug type and cover type.

[0011] As the name implies, a gradual flow channel is one in which the diameter (or cross-sectional dimensions) of the flow channel changes continuously. The most typical example is a tapered flow channel. The gradual flow channel is equipped with a plug-type plug, commonly known as a valve core. Because the plug is stuck in the flow channel and becomes a plug when the valve is closed, it is called a plug-type plug. The plug of this structure is mostly a sphere or a cone (or a spherical table or a frustum), forming a cone-ball fit or a cone-cone fit. The cone-ball fit is easy to process and has a wide range of applications, but the contact between the cone and the ball is line, and the load-bearing capacity is relatively low. The cone-cone fit is a surface contact, with a high load-bearing capacity, but also requires high processing precision, and is often used in heavy-load situations.

[0012] A sudden flow channel is one in which the diameter (or cross-sectional dimension) of the channel changes abruptly, resulting in a plane (or single-curved surface) at the point of the change; this serves as the working surface. The most typical structure of a sudden flow channel is a large and a small cylindrical channel. The dividing interface is usually a plane (if the small channel section is radially distributed along the circumference, the dividing interface can be a cylindrical surface, and so on). This type of flow channel is generally equipped with a cover-plate plug, commonly known as a valve plate, because the working surface of the plug is also a plane (or a similarly shaped single-curved surface). Because the flow channel is a hole and the plug is a plate, this combination is called a hole-plate combination. When fluid flows from the large section to the small section, the working surface of the plug abuts against the working surface of the flow channel, forming a cover plate, completely covering the small section of the channel and preventing fluid from passing through, thereby closing the valve. Hence the name cover-plate plug. Conversely, when fluid flows from the small section to the large section, it pushes the working surface of the plug away, creating a gap with the working surface of the flow channel. The fluid flows through the gap, opening the valve.

[0013] One type of cover-type plug is made of a thin elastic material, utilizing the material's deformation to both act as an auxiliary spring and achieve opening and closing. This is called a diaphragm check valve. Due to its simplicity and low cost, it is widely used, but its load capacity is relatively low. Conversely, using a thicker material for the valve plate allows for surface contact with the flow channel, resulting in a higher load capacity.

[0014] Of course, in theory, it is also possible to use a sudden change flow channel with a plug-type plug, but this is just a deformation of the gradual change flow channel with a plug-type plug, and the effect is worse, so almost no one uses it this way.

[0015] The piston of the present invention can be used with any valve except a diaphragm-type one-way valve, and all valves belong to non-diaphragm-type one-way valves.

[0016] Furthermore, the piston with a one-way valve adopts an air cap structure:

[0017] The so-called air cap structure is a one-way valve in which the plugging body is fixedly connected to the piston rod, becoming the anchor end, while the valve body becomes the floating end. For one-way valves, the fixed end should be called the fixed end, but because the piston as a whole is movable, it is called the anchor end instead. This is in contrast to the usual structure, where the valve body is the anchor end and the plugging body is the floating end. The plugging body (floating end) of the usual structure is similar to an existing valve, so it is called a valve structure. The valve body (floating end) of the new structure is shaped like a cap, so it is called an air cap structure. Specifically, the piston body includes a piston cap (201), a piston core (202), a conical spring (204), and a retaining ring (205).

[0018] The piston cap is a hollow cylindrical body, and the shape and diameter of its outer cylindrical surface are the same as those of the piston matched with the cylinder of the same diameter in the prior art. It slides in an airtight manner with the inner wall of the cylinder and plays the role of an ordinary piston. The piston cap is also a valve body, and the inner left section contains a cylindrical hole for accommodating the piston core, and the inner right section is the monotonic variable diameter flow channel hole of the one-way valve. A retaining ring groove is provided in the cylindrical hole of the left section at a certain distance from the left end face.

[0019] The left portion of the piston core comprises a circular tube, the inner hole (215) of which is used to connect the piston rod (203), and the right portion comprises a plug. The outer diameter of the circular tube is smaller than the outer diameter of the left end of the plug, forming a pre-compression step (213) for spring installation.

[0020] The piston core is coaxially installed in the cylindrical cavity of the piston cap, and the piston core plug cooperates with the piston cap flow channel to form a one-way valve; the retaining ring (205) is installed in the retaining ring groove of the piston cap, and the conical spring (204) is installed between the retaining ring and the preload step (213) to provide preload pressure.

[0021] The flow channel of the piston cap can be of gradual type, and can be matched with a frustum-type or spherical table-type plug to form a cone-cone or cone-sphere fit.

[0022] The flow channel of the piston cap can be of a sudden change type, and can be matched with a cover plate type plug to form an orifice plate combination.

[0023] The advantage of this cap-type structure is that the friction between the piston cap (202) and the cylinder body can be used as the power for opening and closing the piston valve.

[0024] Furthermore, the monotonically variable flow channel of the piston cap is of a sudden change type and is equipped with a cover plate type plug to form an orifice plate combination. The top of the piston cap (231) includes a circular piston cap top (251) made of ceramic material, and the top of the piston core (232) includes a disc-shaped piston core top (252) made of ceramic material. The ceramic can be industrial ceramic, especially silicon nitride and silicon carbide. Since ceramics are difficult to process, after adopting the orifice-plate combination structure, the piston cap top and the piston core top are both simple in shape, and their working surfaces are both flat or outer cylindrical surfaces, which are easy to process.

[0025] Furthermore, the piston core has a mounting hole (221) on the top surface thereof for mounting an ignition device, and the piston rod has a connecting wire channel (222) for laying a connecting wire of the ignition device. In this way, the ignition device can be mounted in the mounting hole (221).

[0026] The basic technical solution of the internal combustion engine provided by the present invention is a 2x2-stroke internal combustion engine. Its structure includes a cylinder body (301), an intake cover (302), a main piston (304) and its driving mechanism, and an auxiliary piston (305) and its driving mechanism. The auxiliary piston is the piston described in each of the above technical solutions, and the one-way valve on the piston is called a piston valve. The main piston is the same as the piston of an existing four-stroke internal combustion engine. The cylinder body (301) is a circular tube, placed horizontally, and has an exhaust port (312) on the right side of the cylinder. The intake cover (302) is a circular disk with a hole in the center, and has multiple air passages (325) parallel to the center hole; the intake cover is installed on the left end face of the cylinder body and is fixedly connected to the cylinder body.

[0027] The auxiliary piston and the main piston are placed opposite each other in the cylinder, and both are in sealing and sliding cooperation with the cylinder wall. The auxiliary piston is located on the left side of the cylinder, with the piston top facing right, and the auxiliary piston rod passes through the center hole of the air intake cover to the left. The main piston is located on the right side of the cylinder, with the piston top facing left, facing the top surface of the auxiliary piston. The space enclosed by the top surfaces of the two pistons and the cylinder wall is the combustion chamber (321), and the surface of the two pistons forming the combustion chamber is the combustion surface. The space enclosed by the air intake cover, the cylinder wall, and the left side of the auxiliary piston is the air intake chamber (322).

[0028] Both pistons can move left and right within a certain range within the cylinder: the auxiliary piston's leftmost limit is called the auxiliary piston's left dead center, and its rightmost limit is called the auxiliary piston's right dead center. The main piston's leftmost limit is called the main piston's left dead center, and its rightmost limit is called the main piston's right dead center. These limits, as well as other positions described below, refer to the combustion surface.

[0029] The exhaust port is a slot or ring in the cylinder wall at the right end. Its width is called the exhaust port width. The left end of the exhaust port serves as the exhaust and intake points: the exhaust point occurs when the piston passes from left to right, and the intake point occurs when the piston passes from right to left. The right dead center of the primary piston is to the right of the exhaust point. The area between these two points is called the exhaust interval, and its width is the exhaust width. The exhaust width is less than or equal to the exhaust port width, meaning that the right end of the exhaust port is to the right of or coincides with the right dead center of the primary piston. The right dead center of the auxiliary piston is within the exhaust interval.

[0030] When the auxiliary piston is at its left dead center, its left side contacts the right side of the intake cap, transferring the gas pressure on the auxiliary piston to the intake cap. The main piston's left dead center is a certain distance to the right of the auxiliary piston's left dead center. This distance represents the minimum compression distance, resulting in the maximum compression ratio.

[0031] The primary and secondary piston drive mechanisms constrain the positional relationship between the two pistons, driving them in a predetermined pattern to achieve the four strokes of the internal combustion engine: 1. Intake Stroke: Initially, both pistons are at the intake point, and the combustion chamber volume is zero. Both pistons move leftward, with the secondary piston's velocity exceeding that of the primary piston, increasing the distance between them and the combustion chamber volume. During this process, the piston valve opens, allowing gas to flow from the intake chamber into the combustion chamber. When the secondary piston reaches its left dead center, it stops moving, the piston valve closes, and the intake stroke ends. The primary piston is now at the compression point. 2. Compression Stroke: During this process, the secondary piston remains stationary at the left dead center, while the primary piston moves from the compression point to its left dead center. At the appropriate time, the gas is ignited or compression-ignited. 3. Power Stroke: During this process, the secondary piston remains stationary at the left dead center, while the primary piston moves rightward from its left dead center to the exhaust point, performing work. 4. Exhaust Stroke: During this process, the primary piston moves rightward from the exhaust point to its right dead center for the first half of its stroke and leftward from its right dead center back to the intake point for the second half of its stroke. The auxiliary piston first stops at the left dead center, waiting for the combustion chamber pressure to drop to a predetermined value. It then moves from the left dead center to the exhaust point to expel the exhaust gases. Two scenarios can then occur: First, the auxiliary piston continues to move right, joining the main piston before finally moving leftward with the main piston to the intake point. This often occurs at low speeds. Second, the auxiliary piston fails to cross the exhaust point, and the main piston returns to the intake point. This often occurs at high speeds. When the two pistons meet at the intake point, the exhaust stroke ends, and the cycle repeats. Thus, the internal combustion engine uses two pistons, each performing two strokes, to complete the existing four-stroke cycle, hence the name of a 2×2-stroke cycle internal combustion engine.

[0032] A further technical solution of the present invention is to adopt back pressure air intake technology to improve the air intake effect.

[0033] The measures are as follows: first, the air intake cover and the cylinder body are sealed, and the auxiliary piston rod and the air intake cover are slidably sealed; secondly, a one-way valve, namely, an air intake valve (401), is installed on the air intake passage of the air intake cover to only allow gas to flow from the air intake passage to the air intake chamber, thereby increasing the air pressure in the air intake chamber during the suction stroke, that is, realizing back pressure intake.

[0034] Backpressure refers to the air pressure behind the auxiliary piston. During the intake stroke, the intake chamber volume decreases. With the intake valve closed, the pressure in the intake chamber naturally rises, creating a higher backpressure. This helps gas flow through the piston valve and into the combustion chamber, hence the name backpressure intake.

[0035] A further technical solution of the present invention is to adjust the volume of the intake chamber to adjust the compression ratio.

[0036] This solution also includes a volume adjustment chamber (402) connected to the air inlet chamber. By changing the volume of the volume adjustment chamber, the total volume of the volume adjustment chamber and the air inlet chamber can be adjusted. By changing the volume of the volume adjustment piston, the pressure at the compression starting point can be changed, thereby adjusting the compression ratio. The volume adjustment chamber can be implemented by a cylinder, called a volume adjustment cylinder. The volume can be changed by changing the position of its piston.

[0037] The invention also includes a return air duct (412) which connects the regulating chamber (or intake chamber) and the intake duct. The opening of the duct is adjustable and closable. When the return air duct is closed, the total volume of the regulating chamber and the intake chamber is determined by the size of the regulating chamber (because the volume of the intake chamber is constant). When the return air duct is fully opened, it is equivalent to the volume of the regulating chamber being infinite, and the compression ratio is adjusted to the minimum value. When it is partially opened, the gas can flow back but will be blocked, which is equivalent to the volume of the regulating chamber being adjusted between its maximum value and infinity.

[0038] In the back-pressure intake technology, if a conventional one-way valve is used as the intake valve, pressure loss will occur. A further technical solution of the present invention is to provide a sliding valve type one-way valve that can use friction to reduce the intake pressure loss.

[0039] This slide valve type one-way valve includes a sleeve (421), a valve plate (422), a conical spring (423), a sealing ring (424), etc. The sleeve is mounted on the auxiliary piston rod and can slide on the rod. The sealing ring provides a seal between the sleeve and the auxiliary piston rod, and also increases the friction between the two. The valve plate is fixed to the right end of the sleeve, and closes the flow channel when it moves to the left. The conical spring provides a leftward elastic force as a pre-tightening force for closing the valve. When the auxiliary piston rod moves to the right, the friction force of the auxiliary piston rod on the sleeve can offset the spring elastic force, thereby reducing the intake pressure loss.

[0040] To accommodate the sliding valve, the original center hole and the intake hole (325) on the intake cover are merged into a large intake hole (432). This increases the intake area, but also brings a problem: the support point of the auxiliary piston core is gone. This can be solved by increasing the thickness and strength of the valve plate, but it will make the valve bulky and difficult to open and close. Therefore:

[0041] Another technical solution provided by the present invention is to add a mixing cover to the left side of the intake cover and a sliding valve retainer on the mixing cover. The retainer supports the sliding valve, which in turn supports the auxiliary piston. This solves the auxiliary piston support problem. Furthermore, the sliding valve retainer is designed to be adjustable, allowing for adjustment of pressure and clearance.

[0042] Another technical solution provided by the present invention is to install an exhaust check valve at the exhaust port that only allows gas to flow outward to prevent exhaust gas from flowing back. The simplest method is to use a diaphragm check valve.

[0043] The diaphragm-type one-way valve has the lowest cost, but has exhaust resistance. Another technical solution provided by the present invention is to install an exhaust slide valve at the exhaust port: the exhaust slide valve includes a slide valve body (601) and a slide valve spring (602); the slide valve body is a section of circular tube, and the inner side of the right end has an inward protrusion (603); the outer side of the slide valve body is in sliding and sealing cooperation with the inner side of the right end of the cylinder shell, and can slide therein; the left side is in contact with the cylinder sleeve (502) and is pressed by the spring (602) on the right side to form an airtight state; the inner diameter of the slide valve body is the same as the inner diameter of the cylinder sleeve, and the length from the left end face to the protrusion (603) is the same as the length of the main piston (304). When the main piston moves to the right to the exhaust point, it can be completely embedded in the slide valve body, and the left end of the main piston is flush with the left end of the slide valve body, and the right end just contacts the protrusion (603); when the main piston continues to move to the right, it drives the slide valve body to move to the right together, thereby opening the exhaust port.

[0044] A further technical solution of the present invention is that the auxiliary piston adopts single-acting drive.

[0045] A single-acting drive consists of a pair of force constraints and a pair of position constraints. The force constraint consists of a unidirectional force-applying component and a force-receiving component, while the position constraint consists of a unidirectional stopper and a stopper. The force of the unidirectional force-applying component is limited, making it flexible; the unidirectional stopper and the stopper are unilateral position constraints, making them rigid. Both the force-receiving component and the stopper are located on the target object. The force applied by the unidirectional force-applying component acts on the force-receiving component, causing the target object to move in the direction of the force until the stopper hits the unidirectional stopper, stopping it. Therefore, the unidirectional stopper limits the target object's range of motion and serves as one endpoint of its motion. For the following, let's assume it is the right endpoint, so the force is also to the right. The unidirectional stopper is also movable. When the stopper moves leftward, if the stopper is restrained by the stopper, the target object will move leftward with it. When the stopper moves rightward, whether the target object follows it depends on the other forces acting on the target object. In this case, the stopper and the constraint object may not follow, and in this case, the stopper and the limiter may separate.

[0046] In the present invention, the target body is the auxiliary piston rod, the force-bearing component and the restricted component are both connected to the auxiliary piston rod, the one-way force-applying component is often a spring, and the one-way limiting component may be a slider on the screw rod, or it may be a cam or a follower on the cam mechanism.

[0047] Single-acting drive can avoid the disastrous consequences of a head-on collision when the two pistons accidentally collide.

[0048] For driving the main and auxiliary pistons, the present invention provides two technical solutions: electric drive and mechanical drive.

[0049] The electric drive technology provided by the present invention is as follows: the main piston drive device includes a linear motor (700), and the main piston is directly connected to the linear motor mover (702) to form a free piston linear motor. The auxiliary piston drive device, due to its smaller power, can use a linear motor or a screw linear motor, the latter being more cost-effective. Of course, the controllers of both need to be carefully designed to ensure the coordination of the two pistons' movements, and the two pistons' movements are also designed according to a predetermined curve. In addition, the auxiliary piston needs to adopt a single-acting drive to prevent catastrophic consequences in the event of an unexpected control error.

[0050] The mechanical drive technology provided by the present invention is as follows: the main piston drive device includes a crankshaft connecting rod mechanism composed of a crankshaft (801), a connecting rod (802), etc., which is the same as the piston structure of an existing internal combustion engine. The auxiliary piston drive device includes a force-sealed cam mechanism composed of a cam (803), a tappet (811), a cross bar (812), a tappet spring (813), a roller (814), a tappet bracket (815), etc.; the auxiliary piston rod (305) is connected to the cross bar, which is connected to the tappet, and a roller is provided at the right end of the tappet; the tappet is inserted into a hole in the tappet bracket and can slide in the hole. Due to the connection, the auxiliary piston rod, cross bar, tappet, and roller slide synchronously left and right; the tappet The spring is passed through the outside of the tappet, with the left end against the tappet bracket and the right end against the right end of the tappet, generating pre-tightening pressure to press the roller against the cam; the cam rotates synchronously with the crankshaft; the cam is designed according to a predetermined curve and can control the auxiliary piston limiter to move according to the predetermined curve; the auxiliary piston limiter is the dynamic intersection of the cam and the horizontal plane of the roller; the cam mechanism also constitutes a single-acting mechanism: the tappet spring is a one-way force-applying component, the tappet is a force-bearing component, the roller is a restricted component, and the cam is a one-way limiting component. Beneficial effects

[0051] The beneficial effects of the present invention are as follows: by using the ventilation piston, a 2x2 stroke cycle mode is constructed, which improves the ventilation quality of the internal combustion engine and also increases the specific power. By using the air cap structure, the friction force is converted into the power for switching the piston valve, thereby improving the switching reliability of the ventilation piston valve. By using the back pressure intake technology, the intake volume is increased; by changing the volume of the adjustable cylinder, the compression ratio can be conveniently adjusted. By using the intake slide valve, the intake resistance is reduced and the charging volume is increased. By using the exhaust one-way valve or slide valve, the exhaust gas backflow is prevented. In short, the performance of the internal combustion engine is improved by a series of technical measures. Through reasonable settings, the present invention is an excellent technical solution. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] The following is a brief description of the accompanying drawings. Each figure is a schematic diagram illustrating the technical solution provided by the present invention, and is not an actual engineering drawing. To highlight the inventive concept, certain components and details have been hidden or simplified, and the components in the figures are not necessarily drawn to scale.

[0053] Figure 1. Schematic diagram of a valve-type check valve piston. Figure 2. Schematic diagram of an air cap piston and a cone-cone check valve piston. Figure 3. Schematic diagram of an air cap piston and a hole-plate check valve piston. Figure 4. Schematic diagram of a ceramic-top air cap piston. Figure 5. Schematic diagram of an air cap piston with an ignition device. Figure 6. Schematic diagram of the structure of a mechanical two-piston internal combustion engine. Figure 7. Schematic diagram of the structure and four strokes of a two-piston four-stroke internal combustion engine. Figure 8. Schematic diagram of the back-pressure intake and variable volume intake chamber of a diaphragm-type check valve. Figure 9. Schematic diagram of the back-pressure intake and variable volume intake chamber of a friction-assisted check valve. Figure 10. Schematic diagram of an exhaust check valve. Figure 11. Schematic diagram of the exhaust slide valve and its operating principle. Figure 12. Schematic diagram of the electric drive, with the main drive being a linear motor and the ventilation drive being a lead screw motor. Figure 13. Schematic diagram of the mechanical drive, with the main drive being the crankshaft connecting rod and the ventilation drive being the cam lifter. Figure 14. Schematic diagram of the cam curve.

[0054] In the figure: 101: piston body, 102: piston top, 103: piston rod, 104: valve type one-way valve, 111: tapered hole flow channel, 112: tapered surface plug, 201: tapered hole type piston cap, 202: frustum type piston core, 203: piston rod, 204: piston spring, 205: retaining ring, 211: piston cap conical surface, 212: piston core conical surface, 213: piston core step, 215: piston rod hole, 221: ignition device mounting hole, 222: ignition device connecting line channel, 231: sudden flow channel piston cap, 232: cover plate type piston core, 241: sudden small flow channel, 242: Mutation-type large flow channel, 243: Mutation-type flow channel working surface, 244: Cover-type piston working surface, 251: Ceramic top of piston cap, 252: Ceramic top of piston core, 301: Cylinder block, 302: Intake cover, 303: Mixing cover, 304: Power piston, 305: Gas exchange piston, 311: Total intake port, 312: Exhaust port, 313: Total exhaust port, 321: Combustion chamber, 322: Intake chamber, 323: Mixing chamber, 324: Exhaust chamber, 325: Intake duct, Lsuc: Nominal cylinder length, Lcmp: Compression length, Lmin: Minimum combustion chamber length , Lov: overcharge length, 401: intake valve, 402: volume control cylinder, 403: volume control cylinder piston, 411: volume control air duct, 412: return air duct, 421: intake valve sleeve, 422: intake valve plate, 423: intake valve conical spring, 424: intake valve sealing ring, 425: intake valve seat, 426: seat locking nut, 427: disc spring, 431: intake valve sleeve step, 432: large intake hole, 501: cylinder shell, 502: cylinder liner, 503: exhaust check valve, 511: cylinder liner exhaust groove, 601: exhaust slide valve, 602: exhaust Sliding valve spring, 603: Main cylinder cam, 700: Linear motor main drive, 701: Linear motor stator, 702: Linear motor mover, 703: Main piston spring, 710: Screw motor ventilation drive, 711: Screw auxiliary drive spring, 712: Screw, 713: Screw slider, 714: Motor, 715: Guide rod, 716: Auxiliary drive bracket, 331: Auxiliary piston rod limiting boss, 332: Guide hole, 801: Crankshaft, 802: Connecting rod, 803: Cam, 811: Tappet, 812: Crossbar, 813: Tappet spring, 814: Roller, 815: Tappet bracket Best Mode for Carrying Out the Invention

[0055] The best embodiment of the present invention is Example 12. Modes for Carrying Out the Invention

[0056] The specific content of the technical solution provided by the present invention is described below with reference to the accompanying drawings and specific embodiments.

[0057] This application describes multiple embodiments, which are illustrative rather than restrictive. To make the objectives, technical solutions, and advantages of the present invention more clearly understood, the embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be noted that, unless there is a conflict, the embodiments and features of the embodiments in this application may be combined with each other in any manner.

[0058] FIG1 is the first embodiment provided by the present invention, which is a technical solution of a piston with a one-way valve.

[0059] As shown in the figure, four tapered holes (111) are provided on the top surface (102) of the piston (101). Four one-way valve plugs (104) are inserted into the holes, and their tapered surfaces (112) cooperate with the tapered holes (111), forming a cone-cone flow channel plug. Its structure is similar to the structure of the intake valve and exhaust valve on the cylinder head of an internal combustion engine in the prior art, except that the cylinder head usually has two intake valves and two exhaust valves, while the piston is all intake valves. Therefore, this structure is also called a valve-type one-way valve. In this way, when the air pressure on the left side of the piston is higher than that on the right side, the one-way valve opens, as shown in the left figure in Figure 1, and gas can flow from the side of the piston rod (103) (i.e., the left side) to the side of the piston top (102) (i.e., the right side); but conversely, when the air pressure on the right side of the piston is higher than that on the left side, the two tapered surfaces fit together, and the one-way valve closes, as shown in the right figure in Figure 1, and gas cannot flow from the left side to the right side.

[0060] In this structure, the flow channel (111) and the piston rod (103) are fixedly connected and are in an active position; the blocking body and its conical surface (112) are relatively movable and are in a passive position.

[0061] Of course, the above description refers to the piston being located in the cylinder block. In order to highlight the key points, the cylinder block is hidden in the figure, and the same applies below.

[0062] FIG2 is a second embodiment of the present invention, which is a better technical solution for a piston with a one-way valve. It is also an embodiment of a one-way valve piston with an air cap and a cone-cone combination. In this structure, the blocking body (202) and its cone surface (212) are fixedly connected to the piston rod (103) and are in the active position; the outer shell and flow channel (211) are relatively movable and are in the passive position. This structure is called an air cap one-way valve due to the shape of the outer shell. As shown in the figure, the entire piston includes a piston cap (201), a piston core (202), a piston rod (203), a piston spring (204), and a retaining ring (205).

[0063] The piston cap (201) is a hollow rotating body with a horizontal line in the left-right direction as its axis. Its outer contour is cylindrical, and the shape and diameter of its outer cylindrical surface are the same as those of the piston matched with the same diameter cylinder in the prior art. The diameter is slightly smaller than the diameter of the cylinder, and it fits in an airtight sliding manner with the inner wall of the cylinder, and can slide airtightly in the cylinder, acting as an ordinary piston. Therefore, a piston ring groove is also drawn on the outer side for installing the piston ring. The piston ring groove will be hidden in the subsequent embodiments. The piston cap is also the valve body of the one-way valve, and its inner side is divided into two sections on the left and right. The right section is a truncated cone hole (211) serving as an air passage, with a tapered mouth facing left. The inner left section is a cylindrical hole with a diameter not less than the diameter of the large end of the left end of the truncated cone hole. A retaining ring groove is provided in the cylindrical hole at a certain distance from the left end. The right annular surface is part of the piston top surface and also part of the combustion chamber.

[0064] The piston core is also a rotating body with the horizontal line in the left and right directions as the axis, and is divided into two sections: the right section includes a frustum, with the conical surface (212) facing rightward, and the right cone small end table is also part of the piston top surface. The left section is a cylinder, whose diameter is smaller than the bottom diameter of the left end of the frustum, forming a step (213) with the frustum part, which serves as a spring fulcrum. The left end of the piston core also has a coaxial countersunk hole (215) for connecting the piston rod;

[0065] The piston cap is sleeved on the right outer side of the piston core, and the piston rod is inserted into the left inner center of the piston core. The piston core conical surface (212) and the piston cap conical hole (211) cooperate to form a one-way valve. The piston cap conical hole (211) is a gradual flow channel, and the piston core conical surface (212) is a blocking body, forming a cone-cone fit. Of course, the conical surface of the piston core can also be replaced with a spherical table surface to form a cone-ball fit. The piston cap can move axially relative to the piston core so that the conical surfaces of the two are in a separated or fitted state. When separated, gas can pass through, and when fitted, gas cannot pass through. The left picture of Figure 2 shows the situation when the core cap is separated and the valve is open; the right picture shows the situation when the core cap is fitted and the valve is closed.

[0066] The retaining ring (205) is installed in the retaining ring groove of the piston cap, and the piston spring (204) is installed between the retaining ring and the step (213) to provide pressure to keep the core cap in contact during static state. This spring is also optional. When the spring is not selected, the retaining ring can also prevent the piston cap from falling out of the piston core.

[0067] The air cap check valve cleverly utilizes the friction between the piston and cylinder wall to help open and close the check valve: When the piston moves to the right, the friction force of the cylinder wall on the piston cap is directed to the left. This, combined with the air pressure and inertia forces, allows the piston cap to press leftward against the piston core, thereby closing the check valve. Conversely, when the piston moves to the left, the friction force of the cylinder wall on the piston cap is directed to the right. This, combined with the air pressure and inertia forces, also allows the piston cap to move leftward away from the piston core, thereby opening the check valve. Therefore, the air cap check valve is a better technical solution.

[0068] FIG3 shows the third embodiment of the present invention, which is also a technical solution for an air cap-type one-way valve. Unlike the second embodiment, the one-way valve uses a sudden change airway with a cover-type blocking body. As shown in the figure, the entire piston includes a piston cap (231), a piston core (232), a piston rod (203), a piston spring (204), and a retaining ring (205).

[0069] Comparing Figure 2, it can be seen that this example is very similar to the second embodiment, differing in the one-way valve structure. This example utilizes a hole-plate structure. In this example, the piston cap (231) includes a small flow channel (214) and a large flow channel (242). The interface (243) between the small and large flow channels is a working surface. The bottom surface (244) of the piston core (232) is also a working surface. When the two working surfaces are in contact, the one-way valve is closed, as shown in the left figure; when the two working surfaces are separated, the one-way valve is open, as shown in the right figure.

[0070] The rest of the structure and working principle of this example are the same as those of the second embodiment, please refer to them and will not be repeated here.

[0071] FIG4 is the fourth embodiment provided by the present invention, which shows a further technical solution: an improvement based on the third embodiment by adding a ceramic top. As shown in the figure, the top of the piston cap (231) includes a ring-shaped ceramic top (251), and the top of the piston core (232) includes a disc-shaped ceramic top (252). The ceramic material can be industrial ceramics such as silicon nitride and silicon carbide, which have excellent properties such as wear resistance and heat insulation, but are difficult to process. According to the solution of this embodiment, the ceramic part is in the shape of a ring and a disc, which is simple in shape and easy to process. In particular, the valve working surfaces of both are flat, which is convenient for grinding; the outer cylindrical surface of the ring is also convenient for grinding.

[0072] The rest of the structure and working principle of this example are the same as those of the third embodiment, please refer to them and will not be repeated here.

[0073] FIG5 is the fifth embodiment provided by the present invention, which shows a further technical solution: an improvement based on the second embodiment by adding an ignition device. As shown in the figure, a mounting hole (221) for mounting the ignition device is provided on the top surface side of the piston core, in which the ignition device is placed. Of course, after the ignition device is installed, this hole should be completely sealed and able to withstand the corresponding pressure. The piston rod is a hollow structure and is provided with a connecting wire channel (222) for laying the connecting wire of the ignition device. The connecting wire for connecting the ignition device is laid in the channel. The ignition device can be an electrically driven igniter such as a spark plug, a voltage igniter, a microwave igniter, etc., and its connecting wire is a wire. The ignition device can be a laser igniter, and its connecting wire is an optical fiber.

[0074] The rest of the structure and working principle of this example are the same as those of the second embodiment, please refer to them and will not be repeated here.

[0075] FIG6 and FIG7 are the sixth embodiment provided by the present invention, which is a basic technical solution of a dual-piston internal combustion engine using the aforementioned one-way valve piston structure.

[0076] As shown in the figure, two pistons are placed opposite each other in the cylinder body (301): the left piston (305) is any one of the pistons with a one-way valve in the aforementioned embodiments, referred to as the ventilation piston in the present invention, also known as the auxiliary piston; the right piston (304) is a piston in the prior art, referred to as the power piston in the present invention, also known as the main piston. An intake cover (302) is provided at the left end of the cylinder body to bear the pressure exerted on the auxiliary piston. The space enclosed by the top surfaces of the two pistons and the cylinder wall is the combustion chamber (321), and the top surfaces of the two pistons are the combustion surface; the space enclosed by the intake cover, the cylinder wall, and the left side of the auxiliary piston is the intake chamber (322). Obviously, both pistons can move left and right within a certain range in the cylinder. The leftmost position that the auxiliary piston can reach is called the auxiliary piston left stop point, and the rightmost position is called the auxiliary piston right stop point; the leftmost position that the main piston can reach is called the main piston left stop point, and the rightmost position is called the main piston right stop point. Each of the above-mentioned stop points and other positions below refer to the combustion surface position.

[0077] Unlike the prior art, the exhaust port (312) of the present invention is a slot or annular band on the cylinder wall at the right end of the cylinder. The right end of the exhaust port coincides with the right dead center of the main piston or is to the right of the right dead center; the left end of the exhaust port is to the left of the right dead center of the main piston. The distance between the left end of the exhaust port and the right dead center of the main piston is a predetermined value, called the exhaust width, which is also an important design parameter. The left end of the exhaust port is the exhaust point and the intake point: the exhaust point when the piston passes from left to right, and the intake point when the piston passes from right to left. When the main piston is to the left of the exhaust point, the exhaust port is naturally closed, and the gas in the combustion chamber cannot be discharged from the exhaust port. When the main piston is to the right of the exhaust point, the exhaust port is naturally open, and the gas in the combustion chamber can enter the exhaust chamber (324) through the exhaust port (312) and then be discharged through the main exhaust port (313).

[0078] In the prior art, the cylinder head is opposite the power piston. In the present invention, the cylinder head is essentially split into two parts: the intake cover (302) and the gas exchange piston (305). The gas exchange piston is movable, which adds a new feature to the internal combustion engine: by having the power piston and the gas exchange piston each operate two strokes, the four strokes of intake, compression, power, and exhaust are achieved. This is as follows:

[0079] 1. Intake Stroke: Initially, both pistons are at the intake point, and the combustion chamber volume is zero, as shown in Figure 7-3A. Then, both pistons move to the left, with the auxiliary piston's speed exceeding that of the main piston. The distance between the two pistons increases, and the combustion chamber volume increases, as shown in Figure 7-3B. During this process, the one-way valve on the auxiliary piston opens, allowing gas to flow from the intake chamber (322) into the combustion chamber (321). Finally, the auxiliary piston reaches its left dead center and stops moving. The one-way valve closes, and the intake stroke ends, as shown in Figure 7-3C. The position of the main piston at this point is called the compression point, and the length of the combustion chamber is called the compression length Lcmp.

[0080] 2. Compression Stroke: Immediately following the previous stroke, the auxiliary piston remains stationary at its left dead center. The main piston continues to move leftward from the compression point, compressing the mixture until it reaches its left dead center, as shown in Figure 7-3D. At this point, the combustion chamber length is at its minimum, referred to as the minimum combustion chamber length, Lmin. Naturally, the combustion chamber volume is also at its minimum. The gases are ignited or compression-ignited at the appropriate time, either at the end of the compression stroke or at the beginning of the power stroke. This is similar to the ignition angle used in conventional technology.

[0081] 3. Power Stroke: Immediately following the previous stroke, the auxiliary piston remains stationary at its left dead center, while the main piston moves rightward from its left dead center to the exhaust point, performing external work. When the auxiliary piston is at its left dead center and the main piston is at the exhaust point, the distance between the two piston combustion surfaces is called the nominal cylinder length, Lsuc, or nominal cylinder length for short.

[0082] 4. Exhaust stroke: Following the previous stroke, the main piston continues to move rightward from its exhaust point until it reaches its right dead center, as shown in Figure 7-3E. It then reverses direction and moves from its right dead center to the intake point. During this period, the exhaust port opens, and the exhaust gas after combustion enters the exhaust chamber (324) through the exhaust port (312) and is then discharged through the main exhaust port (313). The auxiliary piston initially remains stationary at the left dead center. As the exhaust process progresses, the air pressure drops, and the auxiliary piston begins to move rightward until it fits with the main piston. This process actually forces the exhaust gas with reduced pressure out of the combustion chamber, and the volume of the combustion chamber eventually returns to zero, resulting in very thorough ventilation, which is better than the ventilation of existing four-stroke internal combustion engines. At the same time, the volume of the intake chamber continues to increase, sucking fresh gas from the intake duct into the intake chamber. The auxiliary piston then moves synchronously with the main piston until it moves in the opposite direction back to the intake point. This completes the cycle and begins a new round of intake.

[0083] During the exhaust stroke, the auxiliary piston and the main piston typically meet to the right of the exhaust point. The distance from this point to the exhaust point is called the overinflation length, Lov, as shown in Figure 7-3F. Because the intake chamber length is at its maximum at this point, (Lsuc + Lov), its role will be fully demonstrated in the "backpressure inflation and volume adjustment" technique demonstrated in the next embodiment. However, this also depends on the operating speed: at low speeds, the auxiliary piston has ample time to expel exhaust gases and can reach the right side of the exhaust point, resulting in Lov being greater than zero. As speed increases, the exhaust time shortens, and the main piston may have returned just as the auxiliary piston reaches the exhaust point, with Lov approaching zero. At higher speeds, the exhaust time becomes even shorter, and the main piston may have returned before the auxiliary piston reaches the exhaust point, resulting in Lov being less than zero. Clearly, a Lov slightly greater than zero is the design goal.

[0084] The main piston performs only two strokes, one left and one right, achieving the same efficiency as a two-stroke engine. Regarding ventilation, the auxiliary piston performs two strokes, one left and one right, achieving complete exhaust and fresh air intake. This effectively creates forced scavenging by the auxiliary piston. Because each piston performs two strokes, it is called a 2x2-stroke internal combustion engine.

[0085] FIG8 is a seventh embodiment provided by the present invention, showing the technical solution of back pressure inflation and variable compression ratio.

[0086] As shown in Figure 8A, the technical solution for back-pressure inflation is: a one-way valve, namely, an intake valve (401), is installed on the right side of the intake duct (325) on the intake cover (302), so that gas can only flow from the intake duct to the intake chamber. At the same time, an airtight seal is implemented between the intake cover and the cylinder body, and a sliding airtight seal is implemented between the intake cover and the auxiliary piston rod. In this way, during the power stroke and the early stage of the exhaust stroke, the intake valve (401) opens, and gas enters the intake chamber from the intake duct; at the end of the exhaust stroke, after the auxiliary piston reaches its right dead center, the intake valve (401) closes, and gas cannot flow back. As the auxiliary piston moves to the left, the volume of the intake chamber decreases, and the air pressure rises, which is higher than the air pressure during intake. This is the back pressure. The "back" here refers to the back of the piston valve, that is, the pressure on the back of the piston valve increases. Back pressure helps gas pass through the piston valve and flow from the intake chamber to the combustion chamber, increasing the amount of air in the combustion chamber and improving the inflation effect.

[0087] Another measure is to add a volume-adjusting cylinder (402). The right part of the volume-adjusting cylinder is called the volume-adjusting chamber (413), which is connected to the intake chamber through the volume-adjusting air channel (411). The volume-adjusting cylinder has a volume-adjusting piston (403). By changing the position of the volume-adjusting piston, the volume of the volume-adjusting chamber can be changed, thereby adjusting the total volume of the volume-adjusting chamber and the intake chamber (hereinafter referred to as the total volume of the intake chamber).

[0088] To the left of the intake cap is the mixing cap (303), and the space enclosed by the mixing cap and the intake cap is the mixing chamber (323). As the name suggests, the mixing chamber is where the fuel and air mix. However, there are many ways to add fuel, and the addition location naturally varies, so the term "mixing chamber" only applies to certain methods. In this example, the mixing chamber is connected to the intake duct and has the same pressure, so it is considered the intake duct.

[0089] In addition, it also includes a return air duct (412) connecting the mixing chamber and the regulating chamber (or intake chamber). This duct can be closed, opened, or partially opened. When the return air duct is closed, the total volume of the intake chamber is determined by the size of the regulating chamber (because the volume of the intake chamber is constant). When the return air duct is fully opened, the regulating chamber is connected to the intake duct, which is equivalent to the volume of the regulating chamber becoming infinite. When the return air duct is partially opened, the gas can flow back but will be blocked, which is equivalent to the regulating chamber being adjusted between its maximum value and infinity.

[0090] By changing the total volume of the intake chamber and combining it with back pressure technology, the compression ratio can be changed. The principle is as follows:

[0091] Assume the piston area is S, the total intake chamber volume is Vin when the auxiliary piston is at the left dead center, and define the equivalent intake chamber length Lin = Vin / S. When the auxiliary piston is at the right dead center, the total intake chamber volume becomes: (Lin + Lsuc + Lov) S.

[0092] The compression process is actually divided into three sections. The first section is from the auxiliary piston to the right dead center to the intake point. In this section, the main piston presses the auxiliary piston, the volume of the combustion chamber is zero, and compression is performed on the gas in the intake chamber and the regulating chamber together. In the second section, the auxiliary piston reaches its left dead center from the intake point (at the same time, the main piston reaches the compression point from the intake point). In this section, the piston valve is open, and the combustion chamber, intake chamber, and regulating chamber are also connected. Compression is also performed on the gas in the combustion chamber, intake chamber, and regulating chamber together. These two sections can be combined for calculation. Assume that the initial intake pressure is P0, and assume that the intake valve is closed immediately when the auxiliary piston reaches the left dead center. At this time, the air pressure is P1. The compression process is regarded as adiabatic compression, and the adiabatic index is k.

[0093] P1 / P0 = [(Lin+Lsuc+Lov) / (Lin+Lcmp)]^k

[0094] This P1 is obviously greater than P0, and will exert a rightward thrust on the auxiliary piston during the exhaust stroke to help exhaust.

[0095] The third section is from the compression point to the left dead center of the main piston. The piston valve is closed during this section, and compression is only performed on the gas in the combustion chamber. Assuming the gas pressure is P2, we have:

[0096] P2 / P1 = [Lcmp / Lmin]^k

[0097] The final equivalent compression ratio is:

[0098] ε = (P2 / P0)^(1 / k) = [ (Lin+Lsuc+Lov) Lcmp ] / [(Lin+Lcmp) Lmin ]

[0099] Therefore, changing the position of the displacement piston can change Vin, thereby changing Lin and ultimately changing the compression ratio ε.

[0100] Consider the extreme case: when Lin=0, there is ε max =(Lsuc+Lov) / Lmin, this is the maximum compression ratio, which can be considered to be set above 20. When Lin=∞, there is ε min = Lcmp / Lmin, which is the minimum compression ratio and can be considered to be set at around 10. The minimum compression ratio is also the compression ratio when there is no back pressure, which can be achieved by connecting the volume control chamber and the gas mixing chamber. As shown in Figure 8C, the volume control piston is placed at the far left end, and the volume control chamber and the gas mixing chamber are connected through the return channel (412), which can achieve Lin = ∞. Lin = 0 may not be possible, but it can be minimized.

[0101] This provides a convenient method for changing the compression ratio. For example, by using a screw motor with a brake to drive the volume adjustment piston, and using a multi-turn code disk for position detection, the position of the volume adjustment piston can be easily changed, as shown in Figure 8. The screw motor and the multi-turn code disk are not shown in the figure. As can be seen from the figure, when the volume adjustment piston (403) is on the right side of the reflux hole (412), the reflux channel is closed, as shown in the upper sub-figure (8A). At this time, changing the position of the volume adjustment piston can change the volume of the volume adjustment chamber, thereby changing the compression ratio. When the volume adjustment piston is on the left side of the reflux hole, the reflux channel is completely open, as shown in the lower sub-figure (8C). At this time, the gas can flow back to the intake end from the intake chamber through the volume adjustment air channel (411) and the reflux air channel (412), which is equivalent to the volume of the volume adjustment chamber being infinite. When the volume control piston is within the reflux hole position range, the reflux channel is partially blocked and partially open, equivalent to a regulating valve. Gas can flow back but is obstructed, which affects the air pressure P1 when the piston valve is closed, equivalent to adjusting the volume of the volume control chamber between its maximum value and infinity. Therefore, by changing the position of the volume control piston, the compression ratio can be easily changed.

[0102] By changing the compression ratio and then changing the gas concentration, for example, lean gas with a high compression ratio, etc., a variety of working conditions such as different power and high efficiency can be achieved.

[0103] The intake valve (401) shown in FIG8 (8B) is a diaphragm-type one-way valve, which is the lowest cost option. However, in order to overcome the elastic force of the diaphragm, the air pressure entering the intake chamber is slightly lost, which has a certain impact at high speeds.

[0104] Figure 9 shows the eighth embodiment of the present invention, an improvement on the intake valve of the previous example. The friction of the auxiliary piston rod assists in opening and closing the intake valve, reducing intake pressure loss. Furthermore, a stop is added to the mixing cover to absorb the pressure from the auxiliary piston core.

[0105] As shown in Figure 9, the intake valve is a one-way valve with a sudden change in flow path and a valve plate structure. In this example, the center hole on the original intake cover (302) and multiple intake holes (325) are combined to form a large intake hole (432). This hole is the small flow path of the one-way valve. The intake chamber itself is the large flow path, and the right end surface of the intake cover is the working surface of the one-way valve. The valve plate assembly consists of an intake valve sleeve (421), an intake valve plate (422), an intake valve conical spring (423), and an intake valve sealing ring (424). The intake valve sleeve is a circular tube with a boss (431) on the left end. It is mounted on the auxiliary piston rod (305) and can slide left and right along the auxiliary piston rod. There is a groove in the intake valve sleeve hole, in which the intake valve sealing ring (424) is installed. It not only performs a sealing function but also increases the friction between the sleeve and the auxiliary piston rod. The intake valve plate (422) is an elastic disc with a hole in the center, mounted on the right end of the intake valve sleeve. The conical spring (423) is sleeved on the outside of the intake valve sleeve, with the left end abutting against the left end boss (431) of the intake valve sleeve and the right end abutting against the intake cover (302), exerting a leftward elastic force on the intake valve sleeve. In a static state, the intake valve plate (422) is pressed leftward against the right end surface of the intake cover, forming a closed valve state. When the auxiliary piston moves to the right, the auxiliary piston rod exerts a rightward friction force on the intake valve sleeve, driving the intake valve sleeve to move a certain distance to the right. At the same time, the compression spring increases the leftward elastic force, achieving equilibrium at the new position. At the same time, the rightward movement of the sleeve also causes the intake valve plate (422) to leave the right end surface of the intake cover (302), thereby opening the valve. Conversely, when the auxiliary piston moves to the left, the friction force and the elastic force are superimposed, causing the valve to close quickly. 9A in the upper part of FIG9 shows the valve-opening state, and 9B is a partial enlarged view.

[0106] An intake valve retaining seat (425), a retaining seat locking nut (426), and a disc spring (427) are also provided on the left end of the mixing cover. The intake valve retaining seat is a round tube with an outwardly protruding step on the right end and an external thread on the left end. It is inserted into the auxiliary piston rod and is inserted into the hole of the mixing cover from the inside. The disc spring is inserted into the retaining seat, with the left end close to the mixing cover and the right end close to the retaining seat step. The retaining seat locking nut fixes the intake valve retaining seat from the outside and generates a certain preload pressure on the disc spring. During the compression stroke and the power stroke, the auxiliary piston core presses (322) on the intake valve sliding sleeve (421), and the intake valve sliding sleeve presses on the intake valve retaining seat (425). Finally, the disc spring (427) transmits the pressure to the mixing cover. The locking nut and disc spring provide a degree of freedom to adjust the pressure and clearance. Figure 9C at the bottom shows this compression state.

[0107] The present invention changes the exhaust port to the right end, which brings a new problem: when the main piston is located to the left of the exhaust port, the exhaust gas in the exhaust chamber (324) may leak to the right side, which may be the crankcase or the linear motor box, which is undesirable. To solve this problem, the present invention provides two technical solutions: installing a one-way valve and a slide valve at the exhaust port.

[0108] FIG10 is a ninth embodiment provided by the present invention, showing a technical solution of adding an exhaust check valve to the exhaust port.

[0109] As shown in the figure, the cylinder sleeve (502) is installed in the cylinder shell (501), and the main piston (304) can slide in the cylinder sleeve. The cylinder sleeve (502) has a slot (511), and the outer side of the slot (511) is covered with a diaphragm (503) of a diaphragm-type one-way valve. The diaphragm has a pattern processed on it to serve as a valve plate. The valve plate is slightly larger than the slot (511) and can cover the slot. The two are aligned to form a one-way valve. When the pressure difference between the inside and outside of the valve plate exceeds a predetermined value, the diaphragm bends outward, the valve plate opens, and the gas is discharged from the exhaust port (312) through the slot (511). When the pressure difference between the inside and outside of the valve plate is less than the predetermined value, the valve plate is elastically pressed against the cylinder sleeve and the slot (511), closing the exhaust port (312) to prevent exhaust gas from flowing back.

[0110] In order to clearly show the cylinder liner slot (511) and the diaphragm (503), FIG5 cuts through the cylinder shell (501) and the cylinder liner (502), while hiding other irrelevant parts. The cylinder liner was not mentioned in the previous embodiments because the cylinder liner had no technical significance in those solutions and was therefore considered to be included in the cylinder block (301), that is, the cylinder block (301) = cylinder shell (501) + cylinder liner (502).

[0111] FIG11 is a tenth embodiment provided by the present invention, showing a technical solution of adding a slide valve to the exhaust port.

[0112] As shown in the figure, an exhaust slide valve (601) is installed at the exhaust port, with an exhaust slide valve spring (602) on its right side. The exhaust slide valve is generally tubular in shape, with steps on the right side. The inner diameter and length of the circular tube are equal to those of the main piston, allowing the main piston to slide completely into the slide valve, as shown in Figure 11B. The outer diameter of the circular tube is an airtight fit with the cylinder shell, allowing it to slide left and right within the cylinder shell without leakage. The spring (602) exerts a certain leftward thrust on the exhaust slide valve (601).

[0113] During the non-exhaust stroke, the spring presses the slide valve against the cylinder block (or cylinder liner), closing the exhaust port and preventing exhaust gas from flowing back, as shown in Figure 11A. During the exhaust stroke, the main piston (304) enters the slide valve and pushes the slide valve to the right, compressing the spring, opening the exhaust port (312) and allowing the exhaust gas in the combustion chamber to be discharged from the exhaust port (312), as shown in Figure 11B. At the end of the exhaust stroke, the main piston moves left to the suction point and its left side, and the spring (602) pushes the slide valve (601) to the left again, closing the exhaust port.

[0114] FIG12 is an eleventh embodiment provided by the present invention, showing a technical solution of motor-driven main and auxiliary pistons.

[0115] In this embodiment, the main piston is connected to the linear motor system (700) to form a free piston power generation system. The auxiliary piston is connected to the screw motor linear drive system (710) to form a screw drive system.

[0116] The linear motor system (700) consists of a stator (701), a mover (702), and a control driver (not shown). A spring (703) is provided on the right side of the mover. The linear motor provides power to drive the main piston during the intake, compression, and exhaust strokes. The main piston provides power to the linear motor during the power stroke, thus completing the internal combustion engine cycle.

[0117] The screw motor linear drive system (710) consists of a single-acting spring (711), a screw (712), a screw slider (713), a motor (714) and its controller, a guide rod (715), a bracket (716), etc. A coaxial guide hole (332) is provided at the center of the left end of the auxiliary piston rod (305), and a boss (331) for limiting the position is provided at the left end of the auxiliary piston rod. The left end of the guide rod is connected to the bracket, and the right end is inserted into the guide hole (332) of the auxiliary piston rod, forming a slide rail for the auxiliary piston rod. The single-acting spring (711) is sleeved in the guide rod, with the left end pressing the bracket (716) and the right end pressing the auxiliary piston rod, always applying rightward pressure to the auxiliary piston. The screw rod is installed parallel to the auxiliary piston rod and the guide rod, and is connected to the motor (714) and driven by the motor. A screw slider (713) is provided on the screw rod, which is driven by the screw rod and can slide left and right. The screw slider (713) is located on the right side of the auxiliary piston rod limiting boss (331) and can be in contact with or separated from the limiting boss. When in contact, it can force the entire auxiliary piston to move to the left.

[0118] The single-acting spring (711), auxiliary piston rod, limiting boss (331) and screw slider (713) are respectively the limited force-applying object, the force-receiving object, the position-limiting body and the position-limiting body, while the auxiliary piston rod is the target body. Together, they constitute the single-acting drive of the auxiliary piston. This single-acting drive, because it has only limited elastic force and is flexible, can prevent serious damage caused by the two pistons meeting in abnormal situations.

[0119] The first ten embodiments of the present invention each illustrate a specific aspect of the technical solution. For example, Examples 1, 2, 3, 4, and 5 relate to the auxiliary piston, Example 6 relates to a dual piston, Examples 7 and 8 relate to the intake portion, and Examples 9 and 10 relate to the exhaust portion. These technical solutions can be combined with one another. This embodiment incorporates the solutions of Examples 2, 6, 7, and 10, which can be clearly seen in Figure 12 and will not be repeated here.

[0120] FIG13 is the twelfth embodiment of the present invention, illustrating a technical solution for mechanically driving the primary and secondary pistons. In this embodiment, the primary piston is connected to a connecting rod (802), which in turn is connected to a crankshaft (801), forming a crankshaft-connecting rod drive system. This is similar to the prior art and will not be described in detail. The remaining components also adopt the solutions of Examples 4, 6, 8, and 10, and can be seen in the previous figures, particularly FIG6.

[0121] In this embodiment, the auxiliary piston is driven by a cam mechanism composed of a cam (803), a tappet (811), etc. This cam mechanism includes a cam (803), a tappet (811), a crossbar (812), a tappet spring (813), a roller (814), and a tappet bracket (815). The cam is fixed to the crankshaft and rotates synchronously with the crankshaft. The roller (814) is installed at the right end of the tappet and forms a transmission pair with the cam. The tappet is inserted into the tappet bracket (815) and can slide left and right in the bracket. The crossbar is fixedly connected to the left end of the tappet and is also fixedly connected to the auxiliary piston rod (305), so that the auxiliary piston rod and the tappet can translate synchronously. The tappet spring (813) is inserted into the tappet and is located between the bracket and the right end of the tappet, always applying a rightward elastic force to the right end of the tappet. Therefore, the tappet, crossbar, and auxiliary piston all tend to move to the right, and the roller (814) also tends to press against the cam. The tappet, roller, and cam form a force-locked cam mechanism. When the crankshaft rotates, the cam rotates synchronously, pushing the tappet and auxiliary piston to move according to the cam profile, thereby achieving coordinated movement with the main piston according to a predetermined pattern.

[0122] This force-locked cam mechanism is also a single-acting drive. It's easy to see that the rightward force acting on the auxiliary piston comes entirely from the spring. When the combustion chamber gas pressure exceeds the spring force, the auxiliary piston stops at its left dead center, and the roller and cam separate. If the two pistons unexpectedly collide, the auxiliary piston retreats to the left, avoiding a further accident. Similarly, the tappet spring, tappet tip, roller, and cam are respectively the limited force-applying element, the force-receiving element, the position-limiting element, and the position-limiting element, collectively constraining the auxiliary piston's single-acting drive.

[0123] Figure 14 shows a diagram of the kinematic relationship between the primary piston, secondary piston, and stopper. The stopper represents the virtual position where the cam limits the roller's capacity. It is the intersection of the line connecting the cam and roller's axes and the cam's working surface. This diagram also serves as the basis for cam curve design.

[0124] This example uses two sets of cam mechanisms for symmetrical driving, but this is not necessary. Using a single set of drive mechanisms is also feasible, but it is necessary to consider the influence of lateral forces and moments and add stabilizing measures such as the guide rod (715) and guide hole (332) in the previous example.

[0125] In this example, the crankshaft can be connected to a motor for starting and generating electricity, or to a code disk for crankshaft angle detection. These are all existing mature technologies and are not shown in the figure.

[0126] The above embodiments are all single-cylinder engines, but a multi-cylinder engine can be formed by combining multiple single-cylinder engines. According to the existing technology, a single-row in-line type (L-type), a double-row V-type, a horizontally opposed type (H-type), a multi-row W-type, etc. can be formed.

[0127] In the description of the present invention, it should be noted that the terms "upper," "lower," "left," "right," "horizontal," "vertical," "one side," "the other side," "one end," "the other end," "side," "opposite," "four corners," "periphery," "nearby," and the like, indicating positions or location relationships, are based on the positions or location relationships shown in the accompanying drawings and are intended only to facilitate the description of the present invention and simplify the description. They do not indicate or imply that the structures referred to have a specific orientation, are constructed or operated in a specific orientation, and therefore should not be construed as limiting the present invention. In the description of the embodiments of the present invention, unless otherwise expressly specified or limited, the terms "connect," "directly connect," "indirectly connect," "fixedly connect," "install," "assemble," and "divided into sections" should be understood in a broad sense. For example, "connect" can mean a fixed connection, a detachable connection, an integral connection, or an airtight or sliding connection. The terms "install," "connect," and "fixedly connect" can mean a direct connection, an indirect connection through an intermediate medium, or internal communication between two components. "Divided into sections" refers to the appearance of a regular geometric shape such as a "cylinder" or "truncated cone," rather than actual physical division into sections. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to the specific context.

[0128] Although the embodiments of the present invention are described above, the contents described are merely embodiments for facilitating understanding of the present invention and are not intended to limit the present invention. Any person skilled in the art to which the present invention belongs may make any modifications, changes, and substitutions in the form and details of the implementation without departing from the spirit of the present invention, and the resulting modifications shall fall within the scope of protection of the present invention. Industrial Applicability

[0129] The various parts and the complete machine of the present invention can be realized by the existing internal combustion engine industry, and thus have industrial applicability.

Claims

1. A piston in an internal combustion engine cylinder, comprising a piston body (101) and a piston rod (103), wherein the side of the piston body facing the combustion chamber is the piston top surface (102), and the side opposite to the piston top surface is the piston back surface, characterized in that: The piston body includes a piston valve - a non-diaphragm one-way valve that allows gas to flow from the back side of the piston to the top side of the piston but not the other way around; the one-way valve uses the piston body as the valve body, and the valve body includes a monotonic variable diameter flow channel; the one-way valve also includes an object that blocks the flow channel, referred to as a plug; the size of the plug is between the size of the large and small ends of the flow channel, so it can enter the large end of the flow channel but cannot pass through the small end; when the fluid flows from the large head end to the small head end, the plug moves with the fluid to the small head end, and eventually gets stuck in the flow channel due to its large size, blocking the flow channel and closing the valve; conversely, when the fluid flows from the small head end to the large head end, the plug moves away from the small head end, and a gap appears between the plug and the flow channel, so that the fluid can flow through the gap and open the valve; the plug can be a plug type such as a sphere, a spherical table, a cone, a frustum, or a cover plate type, but it cannot be a diaphragm type.

2. The piston according to claim 1, characterized in that: The piston is a gas cap type one-way valve piston, specifically: the piston body comprises a piston cap (201), a piston core (202), a conical spring (204), and a retaining ring (205); the piston cap is a hollow cylindrical body, the shape and diameter of its outer cylindrical surface are the same as those of the piston matched with the same diameter cylinder in the prior art, and it is in airtight sliding cooperation with the inner wall of the cylinder, playing the role of an ordinary piston; the piston cap is also a valve body, the inner left section comprises a cylindrical hole for accommodating the piston core, and the inner right section is a monotonically variable diameter flow channel hole; a retaining ring groove is provided in the cylindrical hole of the left section at a certain distance from the left end face; the left part of the piston core comprises a section of round tube, Its inner hole (215) is used to connect the piston rod (203), and the right part includes a plug; the outer diameter of the round tube is smaller than the outer diameter of the left end of the plug, forming a pre-load step (213) for spring installation; the piston core is coaxially installed in the cylindrical cavity of the piston cap, and the piston core plug cooperates with the piston cap flow channel to form a one-way valve; the retaining ring (205) is installed in the retaining ring groove of the piston cap, and the conical spring (204) is installed between the retaining ring and the pre-load step (213) to provide pre-tightening pressure; the flow channel of the piston cap can be a gradual type, equipped with a frustum or spherical table type plug; the flow channel of the piston cap can be a sudden change type, equipped with a cover plate type plug.

3. The piston according to claim 2, characterized in that: The monotonically variable flow channel of the piston cap is a mutation type and is equipped with a cover plate type plug; the top of the piston cap includes a circular piston cap top (251) made of ceramic material, and the top of the piston core includes a disc-shaped piston core top (252) made of ceramic material.

4. An internal combustion engine comprising a cylinder block, a piston and a drive mechanism thereof, characterized in that: It also includes an air intake cover (302), an auxiliary piston (305) and a driving mechanism thereof; the piston is renamed as the main piston (304); the auxiliary piston is any of the pistons described in claim 1, 2 or 3; the right side of the cylinder body (301) includes an exhaust port (312); the air intake cover (302) includes a centrally-hole disc, with a plurality of air intake passages (325) parallel to the central hole, and its right end face is fixedly connected to the left end face of the cylinder body; the auxiliary piston and the main piston are placed in the cylinder opposite to each other, and both are in sealing and sliding cooperation with the cylinder wall; the auxiliary piston is located on the left side of the cylinder, with the piston top facing right; the main piston is located on the right side of the cylinder, with the piston top facing left; the top surfaces of the two pistons are opposite to each other, and the space enclosed by the top surfaces of the two pistons and the cylinder wall is The space between the two pistons is the combustion chamber (321), and the top surfaces of the two pistons are the combustion surfaces; the space surrounded by the intake cover, the cylinder wall, and the back of the auxiliary piston is the intake chamber (322); both pistons can move left and right within a certain range in the cylinder: the leftmost position that the auxiliary piston can reach is called the auxiliary piston left stop point, and the rightmost position is called the auxiliary piston right stop point; the leftmost position that the main piston can reach is called the main piston left stop point, and the rightmost position is called the main piston right stop point; the various stop points and other positions hereinafter refer to the combustion surface positions; the left end of the exhaust port is the exhaust point and the intake point; the right stop point of the main piston is on the right side of the exhaust point, and the interval formed between these two points is called the exhaust interval, and the width of the interval is called the exhaust width, which is less than or equal to the exhaust port width; The right dead center of the auxiliary piston is located in the exhaust interval; When the auxiliary piston is at its left dead center, the left side of the auxiliary piston just contacts the right side of the intake cover, and the pressure of the gas on the auxiliary piston can be transmitted to the intake cover; the left dead center of the main piston is located at a certain distance to the right of the left dead center of the auxiliary piston, and this distance is called the minimum compression distance; the main and auxiliary piston driving mechanisms constrain the position and movement relationship of the two pistons, and drive the two pistons to move in a predetermined manner to achieve the four strokes of the internal combustion engine:

1. Intake stroke: Initially, the two pistons are both at the intake point, and the volume of the combustion chamber is zero; then the two pistons move to the left, the speed of the auxiliary piston is greater than that of the main piston, the distance between the two pistons increases, and the volume of the combustion chamber increases; during this process, the piston valve opens, and the gas flows from the intake chamber into the combustion chamber; When the auxiliary piston reaches its left dead center, it stops moving, the piston valve closes, and the suction stroke ends; at this time, the position of the main piston is the compression point; 2. Compression stroke: the auxiliary piston stops at the left stop point and does not move, while the main piston moves from the compression point to its left stop point; the gas is ignited or compression-ignited at the appropriate time; 3. Power stroke: the auxiliary piston still stops at its left stop point and does not move, while the main piston moves rightward from its left stop point to the exhaust point and performs work externally; 4. Exhaust stroke: the main piston moves rightward from the exhaust point to its right stop point in the first half of the stroke, and moves leftward from its right stop point back to the intake point in the second half of the stroke; the auxiliary piston first stops at the left stop point and does not move, waiting for the air pressure in the combustion chamber to drop to a predetermined value, and then moves rightward to the exhaust point to discharge the exhaust gas; when the two pistons meet at the intake point, the exhaust stroke ends; and the cycle continues.

5. The internal combustion engine according to claim 4, characterized in that: The air intake cover is sealed and connected to the cylinder body, and the auxiliary piston rod and the air intake cover are slidably and sealedly connected; the air intake cover includes a one-way valve, namely, an air intake valve, at the air intake passage (325), which only allows gas to flow from the air intake passage to the air intake chamber and cannot flow in the opposite direction, thereby increasing the air pressure in the air intake chamber during the intake stroke and realizing back pressure intake.

6. The internal combustion engine according to claim 5, characterized in that: It also includes a volume regulating chamber (402) connected to the air inlet chamber and capable of changing its volume, and the compression ratio can be changed by changing the volume of the volume regulating chamber; it also includes a return air passage (412) connecting the air inlet passage and the volume regulating chamber or the air inlet chamber, and the opening of the return air passage can be adjusted or closed; when it is fully opened, it is equivalent to the volume of the volume regulating chamber being infinite, so as to achieve the minimum compression ratio; when it is partially opened, it is equivalent to the volume regulating chamber being adjusted between its maximum value and infinity.

7. The internal combustion engine according to claim 6, characterized in that: The air intake valve comprises an air intake valve sleeve (421), an air intake valve plate (422), an air intake valve conical spring (423), and an air intake valve sealing ring (424); the air intake valve sleeve is a round tube with a boss (431) at the left end, which is sleeved on the auxiliary piston rod (305) and can slide left and right along the auxiliary piston rod; there is a groove in the air intake valve sleeve hole, in which the air intake valve sealing ring (424) is installed, and the sealing ring not only provides sealing between the sleeve and the auxiliary piston rod, but also increases the friction between the two; the air intake valve plate (422) is an elastic disc with a hole in the center, which is fixedly connected to the right end of the air intake valve sleeve; the air intake cover (302) comprises an air intake hole (432) in the center, which is the small flow channel of the one-way valve, the air intake chamber itself is the large flow channel, and the right end face of the air intake cover is the working face of the one-way valve. The conical spring (423) is sleeved on the outside of the intake valve sleeve, with the left end abutting against the left end boss (431) of the intake valve sleeve and the right end abutting against the intake cover (302), giving the intake valve sleeve a leftward elastic force, and pressing the intake valve plate (422) to the left against the right end surface of the intake cover in a static state, thereby forming a valve-closed state; when the auxiliary piston moves to the right, the auxiliary piston rod applies a rightward friction force to the intake valve sleeve, driving the intake valve sleeve to move a certain distance to the right, while compressing the spring (423) to increase the leftward elastic force, so that the sleeve reaches balance in the new position; at the same time, the rightward movement of the sleeve also causes the intake valve plate (422) to leave the right end surface of the intake cover (302) to open the valve; conversely, when the auxiliary piston moves to the left, the leftward friction force and the elastic force are superimposed, so that the intake valve is quickly closed.

8. The internal combustion engine according to claim 7, characterized in that: The internal combustion engine comprises a mixing cover (303), which is in the shape of a cylinder with a hole at the bottom center, installed on the left side of the intake cover (302), with the barrel mouth facing rightward, sealed and connected with the intake cover, and forming a mixing chamber (323); the mixing cover comprises an intake valve seat (425), a seat locking nut (426), and a disc spring (427); the intake valve seat is a round tube with an outwardly protruding step at the right end and an external thread at the left end, which is inserted into the auxiliary piston rod and inserted into the hole of the mixing cover from the inside; the mixing cover and the intake valve seat, and the seat and the auxiliary piston rod are connected. The piston rods are both sealed with sliding air; the disc spring is inserted into the seat, with the left end pressed against the mixing cover and the right end pressed against the step of the seat; the seat locking nut is threadedly connected to the intake valve seat from the outside, and causes the disc spring to generate a certain pre-tightening pressure; during the compression stroke and the power stroke, the auxiliary piston core presses on the intake valve sleeve (421), and the intake valve sleeve presses on the intake valve seat (425), and finally the disc spring (427) transmits the pressure to the mixing cover; the locking nut and the disc spring provide a degree of freedom to adjust the pressure and clearance.

9. The internal combustion engine according to claim 6, characterized in that: It also includes an exhaust check valve, which is installed at the exhaust port to only allow the gas in the cylinder to flow outward.

10. The internal combustion engine according to claim 6, characterized in that: The invention also comprises an exhaust sliding valve; the exhaust sliding valve comprises a sliding valve body (601) and a sliding valve spring (602); the sliding valve body is a section of a circular tube, and the inner side of the right end has an inward protrusion (603); the outer side of the sliding valve body is slidably sealed with the inner side of the right end of the cylinder body; the left side of the sliding valve body is detachably sealed with the right side of the cylinder sleeve (502), and gas can pass through when the two sides are separated, but gas cannot pass through when they are close together; the sliding valve spring (602) presses the sliding valve body (601) to the left; the inner diameter of the sliding valve body is the same as the inner diameter of the cylinder, and the length from the left end face of the sliding valve body to the protrusion (603) is the same as the length of the main piston (304); when the main piston moves to the right to the exhaust point, it can be completely embedded in the sliding valve body, that is, when the right end just contacts the protrusion (603), the left end face of the main piston is just flush with the left end face of the sliding valve body; when the main piston continues to move to the right, it drives the sliding valve body to move to the right together, thereby opening the exhaust port.

11. An internal combustion engine according to any one of claims 4 to 10, characterized in that: The auxiliary piston drive mechanism includes a single-acting drive mechanism; the so-called single-acting drive mechanism is composed of a pair of force constraint mechanisms and a pair of position constraint mechanisms; the force constraint mechanism includes a unidirectional force-applying component and a force-bearing component, and the position constraint mechanism includes a unidirectional limiting component and a limiting component; the force of the unidirectional force-applying component is limited, and therefore it is also flexible; the unidirectional limiting component and the limiting component are unilateral position constraints, and therefore they are also rigid; the force-bearing component and the limiting component are both located on the target body, and the force applied by the unidirectional force-applying component acts on the force-bearing component, causing the target body to move along the force direction until The restricted component stops when it hits the one-way limiting component; therefore, the one-way limiting component limits the range of movement of the target body and is a movement endpoint of the target body; it may be assumed that the movement endpoint is the right endpoint, and therefore the force is also to the right; the one-way limiting component is also movable, and when the limiting component moves to the left, if the restricted component is limited by the limiting component, the target body will move to the left with the limiting component; when the limiting component moves to the right, whether the target body follows the movement depends on the other forces acting on the target body. It may not follow, and at this time the limiting component and the restricted component may be separated.

12. The internal combustion engine according to claim 11, characterized in that: The main piston drive device comprises a linear motor (700), and the main piston is directly connected to the linear motor mover (702) to form a free piston linear motor; the auxiliary piston drive device comprises a screw motor drive system (710), which comprises an auxiliary piston spring (711), a screw (712), a screw slider (713), a motor (714), a guide rod (715), and a bracket (716); the auxiliary piston rod (305) also comprises a flange (331) and a guide hole (332); the left end of the guide rod is connected to the bracket, and the right end is inserted into the guide hole (332) of the auxiliary piston rod to form a guide rail of the auxiliary piston rod; the auxiliary piston spring (711) is sleeved in the guide rod, the left end presses the bracket (716), and the right end presses the auxiliary piston rod, so as to always apply rightward pressure to the auxiliary piston; the screw rod is installed parallel to the auxiliary piston rod and the guide rod The auxiliary piston rod is next to the auxiliary piston rod and is connected to the motor (714) and driven by the motor; a screw slider (713) is provided on the screw rod and can slide left and right under the drive of the screw rod; the screw slider (713) is located on the right side of the auxiliary piston rod flange (331) and can contact or separate from the flange. When in contact, it can force the flange and the entire auxiliary piston to move to the left; the auxiliary piston spring, the auxiliary piston rod, the screw slider and the auxiliary piston rod flange constitute a single-acting drive mechanism: the auxiliary piston spring is a unidirectional force-applying component, and the auxiliary piston rod is a force-bearing component, and the two constitute a force constraint mechanism; the screw slider is a unidirectional limiting component, and the auxiliary piston rod flange is a limited component, and the two constitute a position constraint mechanism; the auxiliary piston rod is a target body; and a controller is also included, which runs according to a predetermined program to control the linear motor (700) and the screw motor (714) to make the main piston and the screw slider move according to a predetermined curve.

13. The internal combustion engine according to claim 11, characterized in that: The main piston driving device comprises a crankshaft connecting rod mechanism composed of a crankshaft (801), a connecting rod (802), etc.; the auxiliary piston driving device comprises a force-sealed cam mechanism composed of a cam (803), a push rod (811), a push rod spring (813), a roller (814), a push rod bracket (815), etc., wherein the push rod is connected to the auxiliary piston rod; the cam rotates synchronously with the crankshaft; the cam is designed according to a predetermined curve and can control the auxiliary piston limiter to move according to the predetermined curve; the auxiliary piston limiter is the dynamic intersection line of the cam and the horizontal plane of the roller; the force-sealed cam mechanism also constitutes a single-acting mechanism: the push rod spring is a one-way force-applying component, the push rod is a force-bearing component, the roller is a restricted component, the cam is a one-way limiting component, and the push rod and the auxiliary piston rod are target bodies.

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