Motorcycle single-cylinder engine and motorcycle

Abstract

The invention belongs to the technical field of motorcycle engines, and particularly discloses a motorcycle single-cylinder engine and a motorcycle. The single-cylinder engine of the motorcycle comprises a shell assembly, the cylinder assembly is arranged on the shell assembly, the crankshaft is arranged in the shell assembly, a first balancing weight is arranged on the crankshaft, a driving gear is arranged on the crankshaft, a driven gear is arranged in the shell assembly, a second balancing weight is integrally arranged on the driven gear, and a first timing chain wheel used for driving a cam shaft to rotate is arranged on the balance shaft; the clutch assembly is arranged in the shell assembly and located on one side of the air cylinder assembly. The driven gear is arranged on the balance shaft and can be driven by the driving gear to rotate, and the second balancing weight and the driven gear are integrally arranged, so that the structure on the whole balance shaft is more compact, the overall size and weight of the engine are reduced, the lightweight performance of the engine is improved, and the service life of the engine is prolonged. And meanwhile, the assembly difficulty can be effectively reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of motorcycle engines, in particular to a motorcycle single-cylinder engine and a motorcycle. Background Art

[0002] The engine is an important part of a motorcycle. Its main function is to convert the chemical energy of the fuel into mechanical energy to drive the motorcycle. The engine generates heat energy by burning fuel such as gasoline or diesel, which is then converted into mechanical energy to drive the rear wheel of the motorcycle to rotate, allowing the motorcycle to move forward.

[0003] The interior of a motorcycle engine realizes a cyclic process of fuel intake, combustion, and emission through structures such as a crankshaft assembly and a cylinder assembly. In the prior art, spare parts such as a balance shaft for shock absorption and a water pump for heat dissipation are provided inside the engine, but they are all separately arranged inside the engine casing, with low integration performance, resulting in a corresponding increase in the size of the engine. The weight of the engine will be correspondingly heavier due to the assembly and coordination of various parts, which cannot meet the requirements of lightweight and miniaturized engines of racing or imitation racing motorcycles. Summary of the invention

[0004] In view of the above-mentioned shortcomings of the prior art, the object of the present invention is to provide a motorcycle single-cylinder engine and a motorcycle, which are used to solve the problem of low integration performance of internal components of motorcycle engines in the prior art, resulting in large size and heavy weight of the engine.

[0005] To achieve the above-mentioned and other related purposes, the present invention provides a motorcycle single-cylinder engine, comprising:

[0006] Shell assembly;

[0007] A cylinder assembly, wherein the cylinder assembly is arranged on the housing assembly, the cylinder assembly comprises a cylinder and a camshaft, and the camshaft is provided with an intake cam and an exhaust cam;

[0008] A crankshaft is arranged in the housing assembly, a first counterweight is arranged on the crankshaft, a driving gear is arranged on the crankshaft, a timing connecting member is arranged in the housing assembly, the timing connecting member includes a balancing shaft and a driven gear arranged on the balancing shaft, a second counterweight is integrally arranged on the driven gear, and a first timing sprocket for driving the camshaft to rotate is arranged on the balancing shaft;

[0009] The clutch assembly is arranged in the housing assembly and is located on one side of the cylinder assembly.

[0010] Optionally, a water pump impeller is provided on the balance shaft, and the water pump impeller is arranged at an end of the driven gear away from the timing sprocket, and the second counterweight block is arranged on a side of the driven gear close to the water pump impeller, and the second counterweight block includes a first boss and a second boss, the first boss is integrally arranged on the first gear, the first boss extends circumferentially on the first gear with the axis of the first gear as the center, and the second boss extends vertically on the first boss along the first gear toward the water pump impeller, and the width of the second boss is smaller than the width of the first boss.

[0011] Optionally, the angle between the symmetry plane of the first counterweight block and the symmetry plane of the second counterweight block is ±2°.

[0012] Optionally, the camshaft is provided with a flange, the flange is provided with a swing block, the camshaft is provided with a valve core shaft passing through the flange, the flange is provided with a limit assembly, the limit assembly includes a limit block and a limit bearing, the limit block is arranged on the flange, the limit block is provided with a slot, the limit bearing is arranged in the slot, and the valve core shaft passes through the limit bearing.

[0013] Optionally, the cylinder assembly includes a cylinder body, a cylinder head and a cylinder head arranged in sequence from bottom to top, and along the extension direction of the cylinder body toward the cylinder head, the cylinder is inclined toward the direction close to the clutch, and an air intake port is provided on the side of the cylinder head away from the clutch, and an exhaust port is provided on the cylinder head opposite to the air intake port.

[0014] Optionally, an intake valve and an exhaust valve are provided in the cylinder head, and a rocker arm assembly is also provided in the cylinder head, the rocker arm assembly includes an intake rocker arm and an exhaust rocker arm, the intake rocker arm includes a first roller and an intake rocker arm body, the intake rocker arm body is rotatably connected to the cylinder head, the first roller is rotatably connected to the intake rocker arm body, the first roller corresponds to and abuts against the intake cam, and is located above the intake cam, and the intake rocker arm body has an intake push portion that is symmetrically arranged and corresponds to the intake valve.

[0015] Optionally, the exhaust rocker arm includes a second roller and an exhaust rocker arm body, the exhaust rocker arm body is rotatably connected to the cylinder head, the second roller is rotatably connected to the exhaust rocker arm body, the second roller corresponds to and abuts against the exhaust cam, and is located above the exhaust cam, the second roller is offset relative to the center of the exhaust rocker arm body and close to the flange, and the exhaust rocker arm body has a pair of exhaust push portions corresponding to the exhaust valve.

[0016] Optionally, the clutch assembly includes an end cover and a push rod, a sealing block is provided between the end cover and the push rod, a hydraulic groove is provided between the sealing block and the end cover, an oil delivery channel connected to the hydraulic groove is provided on the end cover, and a return spring is provided between the end cover and the inner bottom of the hydraulic groove.

[0017] Optionally, a second timing sprocket is provided on the camshaft, and a chain is wound between the first timing sprocket and the second timing sprocket.

[0018] The present invention also provides a motorcycle, which comprises the above-mentioned motorcycle single-cylinder engine.

[0019] As described above, the single-cylinder motorcycle engine and the motorcycle proposed by the present invention have the following beneficial effects:

[0020] (1) Compared with the prior art, the present invention can rotate under the drive of the driving gear by means of the driven gear arranged on the balance shaft, and the second counterweight block and the driven gear are arranged in an integrated manner, so that the structure of the entire balance shaft is more compact, the length of the balance shaft is shorter, and the weight is lighter. At the same time, integrating the first timing sprocket into the balance shaft can also save the internal space of the engine, so that the overall size and weight of the engine are reduced, thereby improving the lightweight performance of the engine.

[0021] (2) Compared with the prior art, the present invention integrates the first timing sprocket and the second counterweight into the balance shaft, making it more convenient to assemble the engine. There is no need to consider the assembly of various spare parts. After the balance shaft is assembled into the housing assembly, each spare part can achieve the corresponding function, thereby reducing the difficulty of engine assembly and the manual load. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 Shown is a schematic diagram of the overall structure of an embodiment of the present invention;

[0023] Figure 2 Shown is a schematic diagram of the internal structure of an embodiment of the present invention;

[0024] Figure 3 It is a schematic diagram showing the matching structure of a crankshaft and a balance shaft in one embodiment of the present invention;

[0025] Figure 4 Display as Figure 3 Schematic diagram of the back structure;

[0026] Figure 5 Shown is a schematic structural diagram of a timing connection member in one embodiment of the present invention;

[0027] Figure 6 Display as Figure 4 A in the enlarged view;

[0028] Figure 7 Display as Figure 2 Side view of

[0029] Figure 8 Shown is a schematic structural diagram of a camshaft and a limiter assembly in one embodiment of the present invention;

[0030] Fig. 9 Display as Figure 7 A cross-sectional view of

[0031] Fig.10 Shown is a schematic structural diagram of a camshaft in one embodiment of the present invention;

[0032] Fig.11 Shown is a schematic diagram of the internal structure of a cylinder in one embodiment of the present invention;

[0033] Fig.12 Shown is a schematic structural diagram of a second timing sprocket in one embodiment of the present invention;

[0034] Fig.13 Shown is a top view of the internal structure of a cylinder in one embodiment of the present invention;

[0035] Fig.14 Shown is a cross-sectional view of a cylinder in one embodiment of the present invention;

[0036] Fig.15 Shown is a schematic structural diagram of a clutch in one embodiment of the present invention;

[0037] Fig.16 Shown is a cross-sectional view of a clutch according to an embodiment of the present invention.

[0038] Description of reference numerals:

[0039] Housing assembly 1, cylinder block 2, cylinder head 3, cylinder head 4, air inlet 5, exhaust port 6, crankshaft 7, crank arm 8, first counterweight 9, connecting rod 10, driving gear 11, balance shaft 12, driven gear 13, sleeve 14, first timing sprocket 15, chain 1501, second counterweight 16, first boss 1601, second boss 1602, water pump impeller 17, camshaft 18, limit groove 1801, mounting groove 1802, second timing sprocket 1803, valve core shaft 19, lever 1901, flange 20, exhaust cam 21, intake cam 22, swing block 23, fixing groove 2301, limit bearing 24, limit block 25, intake rocker arm body 26, first roller 27, exhaust rocker arm body 28, second roller 29, intake valve 30, exhaust valve 31, fixing spring 32, piston 33, combustion chamber 34, end cover 35, oil delivery channel 36, sealing block 37, hydraulic groove 3701, return spring 38, sealing ring 39, push rod 40. DETAILED DESCRIPTION

[0040] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0041] It should be noted that the diagram provided in the present embodiment only illustrates the basic concept of the present invention in a schematic manner, so the diagram only shows the components related to the present invention rather than drawing according to the number, shape and size of the components during actual implementation. The type, quantity and ratio of each component during actual implementation can be a random change, and the component layout type may also be more complicated. The structure, ratio, size, etc. illustrated in the drawings of the present specification are only used to match the content disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions that the present invention can implement, so they have no technical substantive significance. Any modification of the structure, change of the proportional relationship or adjustment of the size should still fall within the scope of the technical content disclosed by the present invention without affecting the effect that the present invention can produce and the purpose that can be achieved. At the same time, the terms such as "upper", "lower", "left", "right", "middle" and "one" quoted in this specification are only for the convenience of narration, and are not used to limit the scope of the present invention. The change or adjustment of its relative relationship should also be regarded as the scope of the present invention without substantially changing the technical content.

[0042] like Figure 1-Figure 16 As shown, the present invention provides a motorcycle single-cylinder engine and a motorcycle.

[0043] In an exemplary embodiment, a motorcycle single cylinder engine comprises:

[0044] Shell assembly 1;

[0045] The cylinder assembly is arranged on the housing assembly 1, and the cylinder assembly includes a cylinder and a camshaft 18, and the camshaft 18 is provided with an intake cam 22 and an exhaust cam 21;

[0046] A crankshaft 7 is arranged in the housing assembly 1, a first counterweight 9 is arranged on the crankshaft 7, a driving gear 11 is arranged on the crankshaft 7, a timing connecting member is arranged in the housing assembly 1, the timing connecting member includes a balancing shaft 12 and a driven gear 13 arranged on the balancing shaft 12, a second counterweight 16 is integrally arranged on the driven gear 13, and a first timing sprocket 15 for driving a camshaft 18 to rotate is arranged on the balancing shaft 12;

[0047] The clutch assembly is arranged in the housing assembly 1 and is located on one side of the cylinder assembly.

[0048] In this embodiment, the driven gear 13 provided on the balance shaft 12 can rotate driven by the driving gear 11, and the second counterweight 16 and the driven gear 13 are integrally provided, so that the structure of the entire balance shaft 12 is more compact, the balance shaft 12 is shorter and lighter, and at the same time, integrating the first timing sprocket 15 into the balance shaft 12 can also save the internal space of the engine, so the overall size and weight of the engine are reduced, thereby improving the lightweight performance of the engine.

[0049] At the same time, in this embodiment, by integrating the first timing sprocket 15 and the second counterweight 16 into the balance shaft 12, it is more convenient to assemble the engine without having to consider the assembly of various spare parts. After the balance shaft 12 is assembled into the housing assembly 1, each spare part can achieve the corresponding function, thereby reducing the difficulty of assembling the engine and the manual load.

[0050] It is worth mentioning that a shaft sleeve 14 is provided on the balancing shaft 12, and the shaft sleeve 14 is connected to the balancing shaft 12, and the driven gear 13 and the first timing sprocket 15 are both arranged on the shaft sleeve 14, wherein the driven gear 13 and the first timing sprocket 15 can be separately connected to the shaft sleeve 14 or integrally formed on the shaft sleeve 14. In this embodiment, the first timing sprocket 15 and the driven gear 13 are integrally arranged on the shaft sleeve 14. When fixing, it is only necessary to connect the shaft sleeve 14 to the balancing shaft 12, and then the first timing sprocket 15 and the driven sprocket can be installed. This assembly method can improve the assembly efficiency of each component, and the overall performance of the balancing shaft 12 can also be improved.

[0051] In an exemplary embodiment, a water pump impeller 17 is provided on the balance shaft 12, which is arranged at the end of the balance shaft 12 on the side of the driven gear 13 away from the first timing sprocket 15. The water pump impeller 17 is arranged at the end of the driven gear 13 away from the timing sprocket. The second counterweight 16 is arranged on the side of the driven gear 13 close to the water pump impeller 17. The second counterweight 16 includes a first boss 1601 and a second boss 1602. The first boss 1601 is integrally arranged on the first gear. The first boss 1601 extends circumferentially on the first gear with the axis of the first gear as the center. The second boss 1602 extends vertically on the first boss 1601 along the direction of the first gear toward the water pump impeller 17, and the width of the second boss 1602 is smaller than the width of the first boss 1601.

[0052] In this embodiment, the second counterweight 16 is mainly used to ensure the smooth operation of the engine. Specifically, in this embodiment, the second counterweight 16 is integrated into the right side wall of the driven gear 13 so that the second counterweight 16 can be installed synchronously when the driven gear 13 is installed.

[0053] Exemplarily, in this embodiment, the second counterweight 16 includes two parts, the first part is circumferentially extended and arranged on the first gear, and the overall shape is annular, and the second boss 1602 is a boss formed by the outer edge part of the first boss 1601 extending toward the axial direction of the first gear along the direction of the water pump impeller 17, wherein the width of the second boss 1602 is smaller than the width of the first boss 1601 so that the second boss 1602 can be away from the shaft sleeve 14 to facilitate the installation of the water pump impeller 17.

[0054] It is worth noting that if the width of the first boss 1601 is insufficient, a portion of the second boss 1602 can extend to the surface of the driven gear 13, but during the design, it must not affect the matching relationship between the power gear meshing therewith to ensure that the balance shaft 12 can rotate normally. At the same time, the inner edge of the first boss 1601 can also be integrally set on the bushing 14, which can improve the overall performance of the connector.

[0055] It should also be noted that the size of the annular second counterweight 16 is adaptively set according to the specific model of the engine, and the size of the second counterweight 16 (ie, the angle of circumferential extension) can be adjusted according to the size and performance requirements of the engine.

[0056] It should also be noted that in this embodiment, when located at the top dead center, there is a certain angle between the first counterweight 9 and the second counterweight 16, which is defined as the target angle, and the range of the target angle is ±2°. In the process of the driving gear 11 driving the driven gear 13 to rotate, the first counterweight 9 reduces the vibration and noise of the crankshaft 7 assembly. Since the second counterweight 16 rotates synchronously with the crankshaft 7, the corresponding relationship between it and the first counterweight 9 can further offset the inertia of the crankshaft 7, and the shock absorption effect of the entire engine assembly is better, and the noise generated during driving is smaller.

[0057] Exemplarily, in this embodiment, the target angle is 1°.

[0058] Exemplarily, in this embodiment, the target angle is -1°.

[0059] In an exemplary embodiment, a flange 20 is provided on the camshaft 18, a swing block 23 is provided on the flange 20, a valve core shaft 19 passing through the flange 20 is provided on the camshaft 18, a limit assembly is provided on the flange 20, the limit assembly includes a limit block 25 and a limit bearing 24, the limit block 25 is arranged on the flange 20, a groove is provided on the limit block 25, the limit bearing 24 is arranged in the groove, and the valve core shaft 19 passes through the limit bearing 24.

[0060] Exemplarily, a limiting groove 1801 is provided on the outer peripheral surface of the camshaft 18 along its axial direction, and the limiting groove 1801 extends from the end of the camshaft 18 toward the exhaust cam 21. The limiting groove 1801 is mainly used for assembling the camshaft 18. At the same time, a mounting groove 1802 is also provided on the camshaft 18, and the mounting groove 1802 continues to extend along the end of the limiting groove 1801 toward the exhaust cam 21 until it connects with the avoidance groove. The mounting groove 1802 is used to install the valve core shaft 19, wherein the valve core shaft 19 can rotate in the mounting groove 1802. The camshaft 18 is rotatably connected with the valve core shaft 19, and the valve core shaft 19 passes through the flange 20 and the end of the valve core shaft 19 enters the exhaust cam 21. The exhaust cam 21 is correspondingly provided with an avoidance groove for accommodating the valve core shaft 19 to enter.

[0061] In this embodiment, the limit bearing 24 is provided to limit the axial and radial directions of the valve core shaft 19. Since the valve core shaft 19 needs to rotate to realize the corresponding function, due to assembly, long-term wear and other reasons, a certain moving space is provided corresponding to each moving direction of the valve core shaft 19. The valve core shaft 19 is prone to excessive rotation or incomplete rotation during operation, which can easily cause the valve to open prematurely during normal operation of the engine. The limit bearing 24 can limit the axial and radial directions of the valve core to ensure the stability of the valve core shaft 19.

[0062] For example, in an exemplary embodiment, the limiting block 25 is provided with a first protrusion and a second protrusion, the first protrusion and the second protrusion form a limited space, the free end of the swing block 23 can rotate around the rotation center of the swing block 23 in the limited space, the swing block 23 is provided with a fixing groove 2301, and the first protrusion is arranged through the fixing groove 2301. At the same time, the valve core shaft 19 is provided with a lever 1901, the lever 1901 penetrates the transition portion and enters the fixing groove 2301, and the lever 1901 can swing in the overlapping area of ​​the fixing groove 2301 and the limiting space under the drive of the swing block 23.

[0063] It is worth noting that in this embodiment, by setting a limit space, the free end of the swing block 23 is limited to swing only between the overlapping area of ​​the limit space and the fixed groove 2301, so that the swing block 23 can be limited, thereby limiting the rotation angle of the lever 1901 to limit the rotation angle of the valve core shaft 19.

[0064] It should also be noted that a step is formed at the junction of the limit groove 1801 and the installation groove 1802. The formed step has two functions. The first is to be used for the installation of the bearing. The inner end face of the bearing rests on the step to facilitate the positioning of the bearing. The second is to be used for the installation of the camshaft 18. When the camshaft 18 passes through the flange 20, the limit groove 1801 can avoid the limit bearing 24, so that the camshaft 18 can smoothly pass through the flange 20 and be fixed to the flange 20.

[0065] In an exemplary embodiment, the cylinder assembly includes a cylinder block 2, a cylinder head 3 and a cylinder head 4 which are arranged in sequence from bottom to top. A piston 33 is arranged in the cylinder block 2. The piston 33 can be driven by a crankshaft 7 to make reciprocating up and down motions in the cylinder block 2 along its own axial direction, wherein the top of the piston 33, the inner wall of the cylinder block 2 and the bottom of the cylinder head 3 together form a combustion chamber 34. Along the extension direction of the cylinder block 2 to the cylinder head 4, the cylinder is inclined toward the direction close to the clutch, and the overall inclination direction of the cylinder is from the lower right to the upper left. An air inlet 5 is arranged on the side of the cylinder head 3 away from the clutch, and an exhaust port 6 arranged opposite to the air inlet 5 is arranged on the cylinder head 3.

[0066] In this embodiment, by changing the overall inclination direction of the cylinder, the inclination direction of the cylinder is changed from forward inclination to backward inclination, so that the overall center of gravity of the engine is moved backward, thereby optimizing the overall center of gravity position of the motorcycle. The motorcycle is more flexible when driving at low speeds and turning, because the axle load of the rear wheel is larger, which helps the control of the motorcycle. At the same time, it can reduce the burden on the front wheel and reduce the wear of the front wheel.

[0067] For example, the cylinder in this embodiment changes the direction of air intake and exhaust, changing the original rear air intake to the front air intake. The front air intake can make the air intake system more direct and efficient, because the air intake port 5 is located at the front end of the motorcycle, and can directly inhale fresh air from the front, while helping to improve the air intake efficiency, especially when driving at high speeds, the vehicle's forward momentum can be used to increase the air intake volume. Changing the original front exhaust to the rear exhaust helps reduce the impact of the exhaust system on the distribution of the vehicle's center of gravity, because the exhaust system is usually heavy, placing it at the rear of the vehicle helps balance the weight distribution of the vehicle and improve handling stability. At the same time, the rear exhaust can reduce the heat radiation of the exhaust pipe to passengers and drivers, and improve the driving experience.

[0068] It is worth noting that, in this embodiment, the cylinder head 3 and the cylinder cover 4 can be integrated or separated.

[0069] It should also be noted that since the clutch is arranged on the left side of the cylinder and the clutch is connected to the gearbox, which is the weight concentrated part of the engine, therefore, tilting the cylinder towards the direction close to the clutch can help adjust the center of gravity of the entire engine to the rear, which correspondingly improves the performance of the motorcycle.

[0070] It should also be noted that a connecting rod 10 is provided at the bottom of the piston 33, and the connecting rod 10 is eccentrically hinged on the crank arm 8 on the crankshaft 7. When the crankshaft 7 rotates, the crank arm 8 is driven to rotate, and the end of the connecting rod 10 is synchronously driven to follow the crank arm 8 to make a circular motion around the axis of the crankshaft 7. Due to the limitation of the cylinder body 2, the piston 33 is driven by the connecting rod 10 to make a reciprocating motion along the circumference of the cylinder body 2.

[0071] In an exemplary embodiment, an intake valve 30 and an exhaust valve 31 are provided in the cylinder head 3. A rocker arm assembly is also provided in the cylinder head 3. The rocker arm assembly includes an intake rocker arm and an exhaust rocker arm. The intake rocker arm includes a first roller 27 and an intake rocker arm body 26. The intake rocker arm body 26 is rotatably connected to the cylinder head 3. The first roller 27 is rotatably connected to the intake rocker arm body 26. The first roller 27 corresponds to and abuts against the intake cam 22 and is located above the intake cam 22. The intake rocker arm body 26 has an intake push portion that is symmetrically arranged and corresponds to the intake valve 30.

[0072] In this embodiment, the engine is a single-cylinder structure, in which the number of intake valves 30 and exhaust valves 31 are both two. By setting a pair of intake valves 30 and a pair of exhaust valves 31, the intake and exhaust volumes of the entire engine are increased, more fuel can enter the combustion chamber 34 for combustion, and the space in the cylinder body 2 can be simultaneously enlarged to increase the displacement of the motorcycle engine. Then, through the valve core shaft 19 set on the camshaft 18, even if the displacement is increased due to the aforementioned changes, the exhaust valve 31 can be opened in advance through the valve core shaft 19 to reduce the starting pressure in the combustion chamber 34 and increase the displacement of the motorcycle single-cylinder engine to 450cc. At present, motorcycle engines with a displacement of 450cc generally require a two-cylinder structure to be realized, and the single-cylinder structure in this embodiment achieves lightweight and small size at the same displacement, reflecting the performance advantages of the engine in this embodiment.

[0073] Specifically: In this embodiment, through the intake rocker arm body 26, when the convex portion of the intake cam 22 contacts the first roller 27 to lift the first roller 27, since the first roller 27 and the intake pushing portion are located at both ends of the intake rocker arm body 26, the intake pushing portion will be pressed downward (refer to the seesaw principle), driving the intake valve 30 to move downward, so that fuel and air can smoothly enter the combustion chamber 34.

[0074] For example, Figure 10-12As shown, the exhaust rocker arm includes a second roller 29 and an exhaust rocker arm body 28. The exhaust rocker arm body 28 is rotatably connected to the cylinder head 3. The second roller 29 is rotatably connected to the exhaust rocker arm body 28. The second roller 29 corresponds to and abuts against the exhaust cam 21 and is located above the exhaust cam 21. The second roller 29 is offset relative to the center of the exhaust rocker arm body 28 and close to the flange 20. The exhaust rocker arm body 28 has a pair of exhaust push portions corresponding to the exhaust valve 31. The working principle of the exhaust rocker arm in this embodiment is the same as that of the above-mentioned intake rocker arm, except that the second roller 29 is offset and the exhaust push portion is no longer symmetrically arranged, and one exhaust push portion extends from the other in an inclined state. This structural form can shorten the distance between the first roller 27 and the second roller 29, thereby shortening the distance between the intake cam 22 and the exhaust cam 21, and ultimately shortening the overall length of the camshaft 18, reducing the required size of the cylinder head 3, reducing the overall size of the engine, and improving the lightweight performance of the engine and the motorcycle.

[0075] It is worth noting that, in this embodiment, a fixing spring 32 is provided between the intake valve 30 , the exhaust valve 31 and the cylinder head 3 , and the fixing spring 32 is used to reset the intake valve 30 and the exhaust valve 31 so as to facilitate the normal operation of the combustion chamber 34 .

[0076] It should also be noted that the camshaft 18 is provided with a second timing sprocket 1803, and a chain 1501 is wound between the first timing sprocket 15 and the second timing sprocket 1803. When the balance shaft 12 rotates, the first timing sprocket 15 rotates synchronously, and the rotational power is transmitted to the second timing sprocket 1803 through the action of the chain 1501, so as to drive the camshaft 18 to rotate.

[0077] In an exemplary embodiment, the clutch assembly includes an end cover 35 and a push rod 40, a sealing block 37 is provided between the end cover 35 and the push rod 40, a hydraulic groove 3701 is provided between the sealing block 37 and the end cover 35, an oil delivery channel 36 connected to the hydraulic groove 3701 is provided on the end cover 35, and a return spring 38 is provided between the end cover 35 and the inner bottom of the hydraulic groove 3701.

[0078] In this embodiment, the sealing block 37 provided between the end cover 35 and the push rod 40, and the hydraulic groove 3701 formed between the sealing block 37 and the end cover 35 can replace the hydraulic cylinder in the clutch in the prior art, and the hydraulic cylinder separately provided in the clutch can be integrated into the end cover 35 through the sealing block 37. When the oil delivery channel 36 is connected to the hydraulic oil from the outside, the hydraulic oil enters the sealing groove, exerts pressure on the sealing block 37, and pushes the push rod 40 to move. The push rod 40 drives the clutch action mechanism in the clutch to act, so that the friction plate and the clutch plate are combined, generating greater friction, and realizing power transmission. When the hydraulic oil is discharged, under the action of the reset spring 38, the sealing block 37 is reset, and the push rod 40 is reset synchronously. The push rod 40 no longer acts on the clutch action mechanism, so the clutch plate and the friction plate are separated, and the function of the clutch is realized through the above structure.

[0079] Illustratively, in this embodiment, the push rod 40 is disposed on the input shaft, and the input shaft is connected to the gearbox, wherein the push rod 40 can move within a certain range at the end of the input shaft along the axial direction of the input shaft.

[0080] Exemplarily, in this embodiment, a plurality of sealing rings 39 are provided between the sealing block 37 and the end cover 35 to prevent leakage of hydraulic oil.

[0081] It is worth mentioning that in the present embodiment, the oil cylinder originally arranged in the housing assembly 1 can be used through the oil delivery channel 36 and the sealing block 37, so that the internal space of the engine assembly can be used more efficiently. At the same time, the size of the housing assembly 1 becomes smaller, the number of parts inside the housing assembly 1 becomes fewer, the weight becomes lighter, and the wiring inside the housing assembly 1 is simpler, thereby improving the lightweight performance of the engine assembly.

[0082] The present invention also provides a motorcycle, which comprises the above-mentioned single-cylinder engine.

[0083] To sum up, the present invention can rotate under the drive of the driving gear 11 through the driven gear 13 set on the balance shaft 12, and the second counterweight block 16 is integrally arranged with the driven gear 13, so that the structure of the entire balance shaft 12 is more compact, the balance shaft 12 is shorter and lighter, and at the same time, integrating the first timing sprocket 15 into the balance shaft 12 can also save the internal space of the engine. Therefore, the overall size and weight of the engine are reduced, the lightweight performance of the engine is improved, and the assembly difficulty can be effectively reduced.

[0084] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A motorcycle single-cylinder engine, characterized in that: include: Shell assembly; A cylinder assembly, wherein the cylinder assembly is arranged on the housing assembly, the cylinder assembly comprises a cylinder and a camshaft, and the camshaft is provided with an intake cam and an exhaust cam; A crankshaft is arranged in the housing assembly, a first counterweight is arranged on the crankshaft, a driving gear is arranged on the crankshaft, a timing connecting member is arranged in the housing assembly, the timing connecting member includes a balancing shaft and a driven gear arranged on the balancing shaft, a second counterweight is integrally arranged on the driven gear, and a first timing sprocket for driving the camshaft to rotate is arranged on the balancing shaft; The clutch assembly is arranged in the housing assembly and is located on one side of the cylinder assembly.

2. A motorcycle single-cylinder engine according to claim 1, characterized in that: A water pump impeller is provided on the balancing shaft, and the water pump impeller is arranged at an end of the driven gear away from the timing sprocket. The second counterweight block is arranged on a side of the driven gear close to the water pump impeller. The second counterweight block includes a first boss and a second boss. The first boss is integrally arranged on the first gear, and the first boss extends circumferentially on the first gear with the axis of the first gear as the center. The second boss extends vertically on the first boss along the first gear toward the water pump impeller, and the width of the second boss is smaller than the width of the first boss.

3. A motorcycle single-cylinder engine according to claim 2, characterized in that: The angle between the symmetry plane of the first counterweight block and the symmetry plane of the second counterweight block is ±2°.

4. A motorcycle single-cylinder engine according to claim 1, characterized in that: The camshaft is provided with a flange, the flange is provided with a swing block, the camshaft is provided with a valve core shaft passing through the flange, the flange is provided with a limit assembly, the limit assembly includes a limit block and a limit bearing, the limit block is arranged on the flange, the limit block is provided with a slot, the limit bearing is arranged in the slot, and the valve core shaft passes through the limit bearing.

5. A motorcycle single-cylinder engine according to claim 1, characterized in that: The cylinder assembly includes a cylinder body, a cylinder head and a cylinder cover which are arranged in sequence from bottom to top. Along the extension direction of the cylinder body toward the cylinder head, the cylinder is inclined toward the direction close to the clutch. An air inlet is provided on the side of the cylinder head away from the clutch, and an exhaust port is provided on the cylinder head which is arranged opposite to the air inlet.

6. A motorcycle single-cylinder engine according to claim 4, characterized in that: An intake valve and an exhaust valve are provided in the cylinder head. A rocker arm assembly is also provided in the cylinder head. The rocker arm assembly includes an intake rocker arm and an exhaust rocker arm. The intake rocker arm includes a first roller and an intake rocker arm body. The intake rocker arm body is rotatably connected to the cylinder head. The first roller is rotatably connected to the intake rocker arm body. The first roller corresponds to and abuts against the intake cam and is located above the intake cam. The intake rocker arm body has an intake push portion that is symmetrically arranged and corresponds to the intake valve.

7. A motorcycle single-cylinder engine according to claim 6, characterized in that: The exhaust rocker arm includes a second roller and an exhaust rocker arm body, the exhaust rocker arm body is rotatably connected, the exhaust rocker arm body is rotatably connected to the cylinder head, the second roller is rotatably connected to the exhaust rocker arm body, the second roller corresponds to and abuts against the exhaust cam, and is located above the exhaust cam, the second roller is offset relative to the center of the exhaust rocker arm body and close to the flange, and the exhaust rocker arm body has a pair of exhaust push portions corresponding to the exhaust valve.

8. A motorcycle single-cylinder engine according to claim 1, characterized in that: The clutch assembly includes an end cover and a push rod, a sealing block is provided between the end cover and the push rod, a hydraulic groove is provided between the sealing block and the end cover, an oil delivery channel connected to the hydraulic groove is provided on the end cover, and a return spring is provided between the end cover and the inner bottom of the hydraulic groove.

9. A motorcycle single-cylinder engine according to claim 1, characterized in that: The camshaft is provided with a second timing sprocket, and a chain is wound between the first timing sprocket and the second timing sprocket.

10. A motorcycle, characterized in that: It comprises a single-cylinder motorcycle engine as described in any one of claims 1-9.

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