Efficient energy-saving four-stroke engine

Abstract

The invention relates to the field of fuel engines, in particular to an efficient energy-saving four-stroke engine. The piston guide rail is built in the cylinder body, positive pressure originally acting on the cylinder wall is transferred to the piston guide rail, the positive pressure of the piston on the cylinder wall is made to return to zero, friction between the piston and the cylinder is sharply reduced accordingly, the piston is easily driven by the connecting rod, and therefore the efficient and energy-saving effect of the piston system is achieved. An existing cam is transformed into the two-way cam, so that a valve spring can be thrown away, the positive pressure of the ball on the two-way cam is zeroed, the linkage piece drives the valve vertically, the positive pressure of the tappet on the wall of the guide pipe is zeroed, and the efficient energy-saving effect of the valve mechanism is achieved. The method is efficient and energy-saving, and energy can be saved by more than 30%; the structure is simple, manufacturing is easy, cost is low, and risks are avoided; independent innovation is achieved, and development of energy-saving automobiles is promoted.

Description

Technical Field

[0001] The present invention relates to a fuel engine for automobiles, in particular to a high-efficiency and energy-saving four-stroke engine. Background Art

[0002] In recent years, our country has been encouraging the development of new energy electric vehicles, even planning to completely phase out the sale of gasoline-powered vehicles by 2035. However, just when we thought gasoline-powered vehicles were about to be phased out, at the recent annual meeting of the Society of Automotive Engineers of China, the Deputy Director of the First Department of Equipment Industry of the Ministry of Industry and Information Technology stated that while vigorously developing new energy vehicles, we must also simultaneously advance the development of internal combustion engine technology, stimulating the joint development of traditional energy vehicle and internal combustion engine manufacturers. In other words, our country will be tackling a two-pronged approach: developing new energy while also ensuring the innovation and development of internal combustion engine technology. It seems the spring of gasoline-powered vehicles is finally coming back!

[0003] The key to the development of internal combustion engine technology lies in high efficiency and energy conservation, achieving at least 40% savings, while also being easy to manufacture and affordable. Only by achieving both energy efficiency and affordability can an engine be unrivaled globally. The current challenge is achieving high efficiency and energy conservation. We are currently misunderstanding the technology. Only by overcoming this misunderstanding can the internal combustion engine develop.

[0004] The energy-saving effect of an internal combustion engine depends primarily on mechanical efficiency. Improving mechanical efficiency involves increasing thermal efficiency and reducing internal friction. The increased thermal efficiency and reduced internal friction are used to produce external work, significantly improving mechanical efficiency. Current engine manufacturers primarily prioritize improving thermal efficiency, completely ignoring the contribution of reducing internal friction to energy savings. This is a significant misunderstanding, causing China's fuel-powered engines to consistently lag behind global standards.

[0005] A fuel engine absorbs heat, most of which is dissipated, with only a small portion used to produce work. This is a universal principle of heat engines. The percentage of work produced is called thermal efficiency. According to thermodynamic theory, a four-stroke engine should have a thermal efficiency of 55%. However, due to irreversible factors such as ① the non-quasi-static behavior of the gas, ② friction between moving parts, ③ turbulent gas flow, ④ incomplete gas combustion, and ⑤ heat conduction, the actual thermal efficiency is only 40%, a loss of 15 percentage points. To improve thermal efficiency, the natural answer is to address the causes of this loss. Current engine manufacturers have consistently chosen the fourth approach, which is to improve thermal efficiency through full combustion of the fuel. The ultimate goal of full combustion is complete combustion, which is a limiting value and impossible to achieve. With technological advancements, full combustion is approaching this limit, and this path is no longer profitable. Even recovering a single percentage point of loss is difficult.

[0006] Because achieving high energy savings through improved thermal efficiency is difficult, the alternative is to reduce internal friction. Internal engine friction includes the energy consumed by driving the pistons and valves. The operation of the pistons and valves inevitably involves friction, and frictional energy consumption accounts for a significant proportion of total internal friction. The greater the friction ratio, the greater the potential for energy savings through friction reduction. Friction reduction methods include lubrication and eliminating positive pressure. Lubrication technology is highly mature, and saving energy through lubrication is no longer feasible. Therefore, energy savings require eliminating positive pressure. Eliminating positive pressure requires appropriate modifications to the engine structure, creating an entirely new product. This requires significant investment and extensive testing, including engine bench testing, various component tests, vehicle-to-vehicle matching tests, life testing, and subsequent user evaluation of the new vehicle and engine. Finding a company willing to undertake such a project is difficult. Consequently, no engine manufacturer has yet taken this approach, resulting in China's energy-saving fuel vehicles ranking only in the third tier globally. Summary of the Invention

[0007] The purpose of this invention is to overcome the current situation where it is difficult to achieve high efficiency and energy saving by improving thermal efficiency or through lubrication, and to invent a high efficiency and energy saving four-stroke engine that saves energy by eliminating positive pressure. This road is difficult, but we must take it, otherwise our cars can only keep up.

[0008] To eliminate positive pressure, you need to understand its source. The positive pressure in the piston system comes from the diagonal force exerted by the connecting rod on the piston. The axial component of this force drives the piston up and down, while the radial component presses against the cylinder wall through the piston, creating positive pressure from the piston on the cylinder. The positive pressure in the valve system (i.e., the valve train) comes first from the valve springs. The tappets are pressed upward against the cams by the valve springs, creating positive pressure from the tappets on the cams. Secondly, when the cams rotate, the waist of the tappets presses against the walls of the valve guides, creating positive pressure from the tappets on the valve guides.

[0009] Elimination of positive pressure is achieved as follows.

[0010] The positive pressure of the piston on the cylinder is achieved by setting a piston guide rail at the bottom of the cylinder. The guide rail is provided with a long hole along the center axis of the cylinder. Then the skirt of the piston is cut off, retaining its head and top, so that the piston is disc-shaped. A piston rod is fixed to the bottom surface of the disc-shaped piston, and a pin seat is fixed to the bottom end of the piston rod. The connecting rod and the pin seat are hinged through a pin. The two ends of the pin are set in the long hole of the piston guide rail, and the other end of the connecting rod is connected to the crank arm. The crank arm drives the piston to run along the axial long hole on the guide rail through the pin. Since the piston can only run in the axial direction, the positive pressure of the piston on the cylinder is zero (excluding the radial tension of the piston ring).

[0011] In order to eliminate the positive pressure of the tappet on the cam, the valve spring must be thrown away. Without the valve spring, the valve cannot be lifted, so the cam must be modified into a two-way cam that can press the valve down and lift the valve up. The two-way cam is made by processing annular guide rails along the cam profile on both sides of the original cam. The annular guide rails drive the valve up and down through a linkage. There is a horizontal tube on each side of the linkage, and a ball and a short column are arranged in the tube. The horizontal tube spans both sides of the cam, and the front hemisphere of the ball falls on the annular guide rail. A nut is provided outside the tube to lock the ball and the short column in the tube, so that the linkage is suspended under the two-way cam. The bottom surface of the linkage is provided with a hanging hole connected to the tappet; the top of the tappet An upper locking ring, a sealing spring and a lower locking ring are provided, and the valve is suspended on the bottom surface of the linkage part in the order of the upper locking ring, the sealing spring, the hanging hole and the lower locking ring; there is also a valve guide rail, which surrounds the outside of the valve guide tube and is fixed on the cylinder head. Axial straight slots are opened on both sides of the valve guide rail, and a chord section is processed on the side of the linkage part cross tube. The linkage part is placed in the valve guide rail, the cross tube falls into the straight slot, and the chord section is attached to the edge of the straight slot. When the bidirectional cam rotates, the annular guide rail drives the valve through the linkage part, the chord section prevents the linkage part from rotating, and the straight slot allows the linkage part to move up and down only, so that the linkage part can only drive the valve straight up and down, ensuring that the positive pressure of the valve tappet on the valve guide tube returns to zero.

[0012] Eliminating positive pressure has a significant energy-saving effect. By eliminating positive pressure in the piston system, an estimated 3% energy savings are achieved, while eliminating positive pressure in the valve system is estimated to save 1.5% energy, for a total of 4.5% energy savings. This 4.5% energy is fully utilized to produce external work, increasing mechanical efficiency from 15% to 19.5% and reducing internal friction from 25% to 20.5%. Furthermore, by reducing friction, thermal efficiency is estimated to increase by 1.5%, from 40% to 41.5%. This 1.5% increase is used to produce external work, further increasing mechanical efficiency to 21%. The increase in mechanical efficiency from 15% to 21% translates to a 40% energy savings. The actual results are expected to be even better than anticipated.

[0013] The present invention is not only highly efficient and energy-efficient, but also exceptionally simple. As previously mentioned, the present invention builds upon existing engines by adding three guide rails: an annular guide rail on the side of the cam, a valve guide rail around the valve guide, and a piston guide rail at the bottom of the cylinder. However, this also eliminates the valve spring and cuts off the piston skirt. Valve springs and piston skirts are a significant burden on engines. Valve springs are energy-intensive components, requiring work to compress the cam and also to push against them during return. They are also very rigid, with an elastic modulus of approximately 20 N / mm. Upon installation, they are already compressed by 15 mm. During operation, they further compress from 15 mm to 25 mm. This means that the cam requires a force of 300 N to 500 N. This significant force significantly complicates the manufacture of the camshaft. The piston skirt is a massive cylinder, so when the piston is driven, it must be driven along with the skirt, significantly increasing the load on the crankshaft. Furthermore, preventing the tail end of the skirt from scraping against the cylinder naturally increases the difficulty of manufacturing and installation. The guide rails, on the other hand, are much simpler. The annular guide rail is simply a circular groove following the cam profile, making it easy to machine. The valve guide and piston guide rails are simply two components with axial channels for the force-applying components to operate—also simple. Replacing two heavy components with three simple guide rails is a technological innovation, resulting in a simple structure, ease of manufacture, and low cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is the structural diagram of the present invention

[0015] Figure 2 Side view of the piston guide

[0016] Figure 3 Bidirectional cam side view

[0017] Figure 4 Bottom view of linkage

[0018] Figure 5 Side view of the valve guide

[0019] Figure 6 Design drawing of bidirectional cam ring guide

[0020] In the picture: 1 cylinder block 2 cylinder heads 3 cylinders

[0021] 4 crankshafts 5 crank arms 6 connecting rods

[0022] 7 Piston 8 Camshaft 9 Valve guide

[0023] 10 valve lifter 11 piston guide 12 long hole

[0024] 13 piston rod 14 pin seat 15 pin

[0025] 16 bidirectional cam 17 annular guide 18 ball

[0026] 19 linkage 20 cross tube 21 short column

[0027] 22 Nut 23 Locking ring 24 Sealing spring

[0028] 25 lower lock ring 26 valve guide 27 straight notch

[0029] 28 chordal section 29 starting gear 30 crankshaft gear

[0030] 31 timing gear 32 chain 33 mounting hole

[0031] 34 piston rings DETAILED DESCRIPTION

[0032] The object of the present invention is to be achieved in the following manner:

[0033] Figure 1 The two valves are in the closed state, such as Figure 1 As shown, the high-efficiency and energy-saving four-stroke engine includes a cylinder block 1 and a cylinder head 2, which are connected as a whole; a cylinder 3 and a crankshaft 4 are provided in the cylinder block 1, a crank arm 5 is provided on the crankshaft 4, a connecting rod 6 is provided on the crank arm 5, and a piston 7 is provided in the cylinder 3; a camshaft 8 and a valve guide 9 are provided on the cylinder head 2, and a valve lifter 10 is provided in the valve guide 9; a starting gear 29 and a crankshaft gear 30 are provided at both ends of the crankshaft 4, respectively, and a timing gear 31 is provided at one end of the camshaft 8, which is connected to the timing gear 31 via a chain 32, and the gear ratio of the crankshaft gear 30 to the timing gear 31 is 1:2;

[0034] The cylinder body 1 is provided with a piston guide rail 11, the bottom end of the piston guide rail 11 is fixed to the base of the cylinder body 1, the top end of the piston guide rail 11 is fixed to the bottom of the cylinder 3, and the center of the piston guide rail 11 is provided with a long hole 12 along the central axis of the cylinder (see Figure 2 ); the piston 7 has a disc-shaped head and top portion after the skirt portion is cut off, and a piston ring 34 is provided around the head portion. A piston rod 13 is fixedly connected to the bottom surface of the piston 7. The bottom end of the piston rod 13 is fixedly connected to a pin seat 14 with a П-shaped cross section. The top end of the connecting rod 6 is disposed in the inner cavity of the pin seat 14. The pin 15 passes through the axial holes on the pin seat 14 and the connecting rod 6, hingedly connecting the pin seat 14 and the connecting rod 6. The two ends of the pin 15 are disposed in the elongated hole 12 of the piston guide rail 11. The other end of the connecting rod 6 is hingedly connected to the crank arm 5.

[0035] The camshaft 8 is provided with a bidirectional cam 16, and the two sides of the bidirectional cam 16 are respectively processed with a ring guide 17 along the cam profile (see Figure 3), an annular guide rail 17 is used for the ball 18 to run therein, the width of the annular guide rail 17 is equal to the diameter of the ball 18, and its depth is equal to the radius of the ball 18; a linkage member 19 with a U-shaped cross section is provided on each side of which a cross tube 20 is provided. The two cross tubes sandwich the annular guide rail 17 in the middle, and the cross tubes 20 are provided with balls 18 and short columns 21. The outer ends of the cross tubes 20 are provided with nuts 22. The nuts 22 lock the balls 18 and short columns 21 in the tubes. The front hemisphere of the ball 18 falls into the annular guide rail 17, so that the linkage member 19 is suspended below the bidirectional cam 16. The bottom surface of the linkage member 19 is provided with a hanging hole 33 for connecting to the valve tappet 10 (see Figure 4 ); The top of the valve lifter 10 is provided with an upper locking ring 23, a sealing spring 24 and a lower locking ring 25. The lower locking ring 25 is located below the hanging hole 33, and the upper locking ring 23 and the sealing spring 24 are located above the hanging hole 33. The upper and lower locking rings sandwich the sealing spring 24 and the linkage member 19, so that the valve lifter 10 is suspended below the linkage member 19; a valve guide 26 with a U-shaped cross section, the bottom surface of which passes through the valve guide 9 and is then fixed to the cylinder head 2, and straight notches 27 are opened on both sides (see Figure 5 ), the side of the transverse tube 20 is processed with a vertical tangent section 28 (see Figure 5 ), the linkage member 19 is arranged in the valve guide rail 26, the cross tube 20 falls into the straight slot 27, and the chord section 28 is attached to the edge of the straight slot 27.

[0036] The cross tube 20 may also be provided with only a short column 21 , and a nut 22 is provided at the outer end of the cross tube 20 , which locks the short column 21 in the tube, and the front end of the short column 21 falls into the annular guide rail 17 , so that the linkage member 19 is suspended below the bidirectional cam 16 .

[0037] The working process of the engine is as follows:

[0038] The crankshaft drives the connecting rod through the crank arm, and the connecting rod applies an oblique force to the piston guide rail through the pin. This force is decomposed into axial and radial components on the piston guide rail. The axial component drives the piston to vibrate up and down through the piston rod, while the radial component transfers the positive pressure originally acting on the cylinder wall to the piston guide rail, reducing the positive pressure of the piston on the cylinder wall to zero (excluding the radial tension of the piston ring). The friction between the piston and the cylinder is sharply reduced, thereby achieving a high efficiency and energy saving effect. The radial force pressing on the piston guide rail will also generate friction. Because the contact surface between the pin and the piston guide rail is only one point, like a ball bearing, the friction between the pin and the sliding rail is extremely small, allowing the crankshaft to work easily and reducing internal friction.

[0039] The crankshaft gear drives the bidirectional cam via a chain and timing gear. The bidirectional cam drives the linkage via a ball bearing. The linkage drives the valve downward via the lower locking ring of the tappet, and then upward via the sealing spring and upper locking ring. The valve guide ensures that the linkage drives the valve in a straight line. Because the linkage is suspended on the annular guide only by the ball bearing, the positive pressure of the ball bearing on the bidirectional cam is zero. Since the linkage drives the valve in a straight line, the positive pressure of the tappet on the guide tube wall is also zero, thus achieving efficient energy saving. There is friction between the linkage and the valve guide, but the contact surface is only a short line, so the friction is extremely small, reducing internal friction.

[0040] The theory of the engine places great emphasis on the design of the cam profile. An optimized profile design plays a significant role in improving thermal efficiency. For a bidirectional cam, the profile design is the centerline design of the annular guide rail. If the centerline is well designed, thermal efficiency can be further improved. The centerline is designed based on the valve lift s. The centerline includes the arc-shaped base circle AEB and the convex part CFD (see Figure 6 ), the radius of the base circle is R=3s, the radius of the protrusion is r=2s, the distance between the centers of the two arcs is O1O2=2s, and the two arcs are connected by tangents AC and BD. It can be proved that the base circle is 240° and the protrusion is 120°. When the annular guide rail works on the base circle, the linkage will remain stationary and the valve will remain closed; when the annular guide rail works on the protrusion, the linkage will move up and down in the straight slot of the valve guide rail under the drive of the two-way cam, and the valve will open and close under the drive of the linkage. The straight line tangent to the two arcs allows the ball to pass smoothly through the connection between the two arcs; the arc-shaped protrusion not only allows the ball to run easily in the groove, but also makes the protrusion fat and wide. The fat and wide protrusion allows the valve to open quickly to the second maximum and then to the maximum, so the intake is sufficient and the exhaust is thorough, which improves the thermal efficiency of the engine.

[0041] Ensuring that the cylinder does not leak is an iron rule of the engine, and the design of the sealing spring effectively achieves this iron rule. Since the cylinder will have a local period of negative pressure of 0.1-0.3 atmospheres, it will leak when the pressure is negative. In order to prevent leakage, it is necessary to give the valve an upward thrust. Assuming that the bottom area of ​​the valve cover is 10cm 2This thrust is 3 kg, plus a safety factor, it is 4 kg. This 4 kg thrust is provided by the sealing spring. That is to say, during assembly, the sealing spring has been compressed, so that the upper locking ring is always subjected to an upward thrust of 4 kg. When the cam rotates to the protruding part, the linkage will press the valve downward through the lower locking ring to open it. When it is opened to the maximum, the linkage in turn pushes the valve upward through the sealing spring and the upper locking ring, causing the valve to move upward. When the valve moves upward to the point where it is closed but not yet tightly closed, the valve cover is blocked by the cylinder intake (exhaust) port, and the valve cannot move upward. However, the linkage must continue to move upward. At this time, the sealing spring is compressed, causing a small gap to appear between the lower locking ring and the linkage. When the cam rotates to the base circle, the linkage stops moving upward. As the linkage continues to move upward, it will push the valve upward through the sealing spring and the upper locking ring, causing the valve cover to close tightly on the cylinder intake (exhaust) port with a pressure of 4 kg, ensuring that the cylinder is leak-proof. This force is maintained until the valve opens. Since the sealing spring has the function of telescoping, the bidirectional cam will not be stuck.

Claims

1. A high-efficiency, energy-saving four-stroke engine comprising a cylinder block and a cylinder head, the cylinder block and the cylinder head being integrally connected; a cylinder and a crankshaft are disposed within the cylinder block, a crank arm is disposed on the crankshaft, a connecting rod is disposed on the crank arm, and a piston is disposed within the cylinder; a camshaft and a valve guide are disposed on the cylinder head, and a valve lifter is disposed within the valve guide; a starter gear and a crankshaft gear are respectively disposed at both ends of the crankshaft, a timing gear is disposed at one end of the camshaft, the crankshaft gear is connected to the timing gear via a chain, and the gear ratio of the crankshaft gear to the timing gear is 1:2; and characterized in that: A piston guide is provided in the cylinder body, and a long hole along the cylinder axis is opened in the center of the piston guide. A piston rod is fixed to the bottom surface of the piston, and a pin seat is fixed to the bottom end of the piston rod. The pin seat and the connecting rod are hinged together. Both ends of the pin are set in the long hole of the piston guide, and the other end of the connecting rod is hinged to the crank arm. A bidirectional cam is provided on the camshaft, a linkage is suspended below the bidirectional cam, a valve tappet is suspended at the bottom of the linkage, a valve guide rail, the bottom surface of which passes through the valve guide and is fixed on the cylinder head, and the linkage is connected to the valve guide rail.

2. The high-efficiency and energy-saving four-stroke engine according to claim 1, characterized in that: The bottom end of the piston guide rail is fixed on the base of the cylinder body, and the top end of the piston guide rail is fixed on the bottom of the cylinder.

3. The high-efficiency and energy-saving four-stroke engine according to claim 1, characterized in that: The cross section of the pin seat is П-shaped, the top end of the connecting rod is arranged in the inner cavity of the pin seat, and the pin passes through the axial holes on the pin seat and the connecting rod, so that the pin seat and the connecting rod are hinged together.

4. The high-efficiency and energy-saving four-stroke engine according to claim 1, characterized in that: The piston is a disc-shaped head and top excluding the skirt, and a piston ring is arranged around the head.

5. The high-efficiency and energy-saving four-stroke engine according to claim 1, characterized in that: The two sides of the bidirectional cam are respectively processed with a circle of annular guide rails along the cam profile, and the annular guide rails are used for the balls to run between them. The width of the annular guide rails is equal to the diameter of the balls, and the depth thereof is equal to the radius of the balls.

6. The high-efficiency and energy-saving four-stroke engine according to claim 1, characterized in that: The cross section of the linkage part is U-shaped, with a horizontal tube on each side. The two horizontal tubes clamp the annular guide rail on the bidirectional cam in the middle. Balls and short columns are arranged in the horizontal tubes. Nuts are provided at the outer ends of the horizontal tubes. The nuts lock the balls and short columns in the tubes. The front hemisphere of the ball falls into the annular guide rail, so that the linkage part is suspended under the bidirectional cam.

7. The high-efficiency and energy-saving four-stroke engine according to claim 1, characterized in that: The top of the valve tappet is provided with an upper locking ring, a sealing spring and a lower locking ring. The lower locking ring is located below the hanging hole, and the upper locking ring and the sealing spring are located above the hanging hole. The upper and lower locking rings clamp the sealing spring and the linkage part in the middle, so that the valve tappet is suspended below the linkage part.

8. The high-efficiency and energy-saving four-stroke engine according to claim 1, characterized in that: The cross section of the valve guide is U-shaped, with straight slots on both sides. The side of the linkage cross tube is processed with a vertical chord section. The linkage is arranged in the U-shaped guide rail, the cross tube falls into the straight slot, and the chord section is attached to the edge of the straight slot.

9. The high-efficiency and energy-saving four-stroke engine according to claim 1, characterized in that: A short column is arranged in the transverse tube, and a nut is arranged at the outer end of the transverse tube. The nut locks the short column in the tube, and the front end of the short column falls into the annular guide rail, so that the linkage part is suspended below the bidirectional cam.

10. The high-efficiency and energy-saving four-stroke engine according to claim 1, characterized in that: The center line of the bidirectional cam annular guide is designed based on the valve lift s. The center line includes an arc-shaped base circle and a protruding part. The radius of the base circle is 3s, the radius of the protruding part is 2s, the centers of the two arcs are 2s apart, and the two arcs are connected by a tangent. The annular line formed by the two arcs and the tangent is the cam profile. The base circle of the cam profile is 240°, and the protruding part is 120°.

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