A motorcycle engine

Abstract

The present invention provides a motorcycle engine, belonging to the technical field of motorcycles. It solves the problem that it is difficult for existing motorcycle engines to take into account both the stability of a water pump and the convenience of adjusting the valve clearance. The motorcycle engine includes a cylinder head, which has an upper joint surface for cooperating with a cylinder cover and a lower joint surface for cooperating with a cylinder body. A camshaft and a valve are installed in the cylinder head. The joint surface is inclined relative to the lower joint surface along the length direction of the camshaft. The higher edge of the upper joint surface is higher than the camshaft. The cylinder head is provided with a mounting hole coaxially arranged with the camshaft on the side wall where the higher edge of the upper joint surface is located. The lower edge of the upper joint surface is lower than the top surface of the valve stem when the valve is in a closed state. The motorcycle engine takes into account both the stability of a water pump and the convenience of adjusting the valve clearance.

Description

Technical Field

[0001] The invention belongs to the technical field of motorcycles and relates to a motorcycle engine. Background Art

[0002] The motorcycle engine includes a cylinder head, a cylinder cover fixed on the top of the cylinder head, and a cylinder body fixed on the bottom of the cylinder head. A combustion chamber is provided in the cylinder body, and a piston is provided in the combustion chamber. The piston drives the crankshaft in the crankcase below to operate through a connecting rod, and an intake channel and an exhaust channel connected to the top of the combustion chamber are provided in the cylinder head. Both the intake channel and the exhaust channel are provided with valves. A camshaft and a rocker arm shaft are also provided in the cylinder head. A rocker arm is provided on the rocker arm shaft. One end of the rocker arm abuts against the cam on the camshaft, and the other end abuts against the top of the valve. The camshaft rotates to drive the rocker arm to swing, thereby driving the valve to move to achieve the intake and exhaust of the combustion chamber. For engines that require water cooling, a water pump needs to be installed on the side of the cylinder head. The pump shaft of the water pump needs to be coaxially arranged with the camshaft, and then the pump shaft is driven to rotate by the camshaft.

[0003] For example, the water pump mounting structure of an internal combustion engine disclosed in patent document (200910262442.2) has semicircular notched surfaces on both the cylinder head and the cylinder head cover. When the cylinder head cover fixing cover is arranged on the cylinder head, the two semicircular notched surfaces are connected to form a mounting hole. The pump shaft of the water pump passes through the mounting hole. At the same time, a sealing assembly needs to be arranged between the pump shaft and the mounting hole for sealing. However, since the sealing assembly is arranged at the joint position of the cylinder head and the cylinder head cover, the deterioration of the fit between the cylinder head cover and the cylinder head during long-term use will affect the roundness of the mounting hole. In addition, the disassembly and assembly of the cylinder head cover during the later maintenance will also affect the sealing of the pump shaft and the mounting hole by the sealing assembly.

[0004] In response to the above problems, the patent document (201520866534.2) discloses a water-cooling circulation system for an engine, in which the edges of the cylinder head are relatively high, the camshaft is completely sunken to the middle of the cylinder head, and a complete mounting hole can be opened on the higher side wall of the cylinder head. The mounting hole is concentric with the camshaft, and the water pump is installed on the side of the cylinder head, and the pump shaft of the water pump passes through the mounting hole to connect with the camshaft. The complete mounting hole on the cylinder head makes the pump shaft more stable, but there is also the problem of increased difficulty in repairing the internal components of the cylinder head, such as valve clearance adjustment. The valve clearance is set to ensure the normal operation of the engine valve mechanism. Since the valve mechanism is in a high-speed state when working, The temperature is high, so if the valve stem stretches after being heated, it will automatically push open the valve, causing the valve and valve seat to not close tightly, causing air leakage. To avoid this phenomenon, a certain gap is left between the top of the intake and exhaust valve stem and the rocker arm when designing the valve mechanism. This gap is the valve clearance. The valve clearance needs to be adjusted during the engine assembly process. When adjusting, it is necessary to first insert a flat measuring ruler into the valve clearance for measurement. In order to install the water pump more stably in the above-mentioned engine, the cylinder head height is higher and the camshaft is at the lower layer, resulting in a lower valve clearance position. When measuring, the measuring ruler needs to be inserted into the cylinder head, which is difficult to operate and causes the valve clearance adjustment to be inconvenient. Summary of the invention

[0005] The purpose of the present invention is to solve the above problems in the existing technology and propose a motorcycle engine to solve the problem that the existing motorcycle engine is difficult to balance the stability of the water pump and the convenience of valve clearance adjustment.

[0006] The object of the present invention can be achieved through the following technical solutions: a motorcycle engine, including a cylinder head, the cylinder head having an upper joint surface for cooperating with a cylinder cover and a lower joint surface for cooperating with a cylinder body, a camshaft and a valve installed in the cylinder head, characterized in that the joint surface is inclined relative to the lower joint surface along the length direction of the camshaft, the higher edge of the upper joint surface is higher than the camshaft, and the cylinder head is provided with a mounting hole coaxially arranged with the camshaft on the side wall where the higher edge of the upper joint surface is located, and the lower edge of the upper joint surface is lower than the top surface of the valve stem when the valve is in a closed state.

[0007] The cylinder head is matched with the upper joint surface of the cylinder head and is fixed on the cylinder head, the cylinder body is matched with the lower joint surface of the cylinder head and is fixedly connected to the cylinder head, and the cylinder body is roughly horizontally arranged, so that the lower joint surface is roughly horizontal, and therefore the upper joint surface is in an inclined state, and the inclined upper joint surface makes one side of the cylinder head higher and the other side relatively lower, so that the side wall on the higher side of the cylinder head has enough space for installing the water pump, and a complete mounting hole is opened for the pump shaft to pass through, and at the same time, the water pump shaft and the camshaft can be concentrically arranged, so that the camshaft drives the water pump to operate, and by opening a complete mounting hole on the side wall of the cylinder head, the water pump is installed on the cylinder head, and the pump shaft and the complete mounting hole are The complete mounting holes are matched to ensure the installation stability and sealing at the mounting holes, and then ensure the stability of the water pump, and the lower edge of the upper mating surface is lower than the top surface of the valve stem. Therefore, when the valve clearance needs to be adjusted, the staff can insert the measuring ruler horizontally from the outside to the inside of the lower side of the cylinder body into the valve clearance above the valve to measure the valve clearance width and adjust the valve clearance according to the measurement results, making the valve clearance adjustment more convenient. That is, the present application installs the water pump through the higher side of the cylinder head, and adjusts the valve clearance through the lower side of the cylinder head through the inclined setting of the upper mating surface, thereby taking into account both the stability of the water pump and the convenience of valve clearance adjustment.

[0008] In the above-mentioned motorcycle engine, there are two valves and they are respectively located on both sides of the camshaft, and the upper ends of the two valve stems are respectively close to the two inclined edges of the upper joint surface, and the position of the inclined edges of the upper joint surface relative to the adjacent valve stems is lower than the top surface of the adjacent valve stems. The position of the valve corresponds to the position of the combustion chamber in the cylinder body, so it is roughly in the middle position between the high side and the low side of the cylinder head, but the inclined setting of the valve makes the valve stem closer to the inclined edge of the upper joint surface. For this reason, the position of the inclined edge of the upper joint surface relative to the adjacent valve stem is lower than the top surface of the adjacent valve stem. When adjusting the valve clearance, the measuring ruler can be directly inserted from the inclined edge of the upper joint surface, reducing the insertion length, so that the insertion end of the measuring ruler is easier to control, further improving the convenience of valve clearance adjustment.

[0009] In the above-mentioned motorcycle engine, a rocker arm is also installed on the cylinder head, one end of the rocker arm can be against the cam of the camshaft, and the other end is screwed with an adjusting bolt, the lower end of the adjusting bolt is opposite to the top of the valve stem, when the valve is in a closed state and the rocker arm is against the cam of the camshaft, a valve clearance is formed between the lower end surface of the adjusting bolt and the top surface of the valve stem, the width of the valve clearance gradually increases from one end to the other end, and the end with a larger valve clearance width faces the inclined edge of the upper joint surface adjacent to the valve. One end of the valve clearance is larger and the other end is smaller, and the end with a larger valve clearance width faces the inclined edge of the upper joint surface, so that the measuring ruler can be inserted into the end with a larger valve clearance width from above the inclined edge, which is easier to insert, further improving the convenience of valve clearance adjustment.

[0010] In the above motorcycle engine, the height of the higher edge of the upper joint surface is greater than the height of the cam lobe tip on the camshaft when it faces upward, so that the higher side of the cylinder head has enough height for opening the mounting hole, and the camshaft can pass through the mounting hole when it is installed, which is convenient for the installation of the camshaft.

[0011] In the above motorcycle engine, the cylinder head has a chain cavity, the higher edge of the upper joint surface is located on the side of the cylinder head where the chain cavity is located, and a sprocket is fixed to the camshaft, the sprocket is located in the chain cavity, and the higher edge of the upper joint surface is lower than the top of the sprocket, so that the top of the sprocket is higher than the higher side of the cylinder head, which is convenient for the installation of the chain.

[0012] In the above motorcycle engine, the angle between the upper joint surface and the lower joint surface is an acute angle. Although the upper joint surface is inclined, the inclination is not large, so that the upper joint surface plays a certain supporting role on the cylinder head and ensures the stability of the overall structure.

[0013] In the above motorcycle engine, the cylinder head is also provided with two rocker shaft holes, each of which is fixed with a rocker shaft, and the two rocker shafts are arranged parallel to the camshaft, and the two rockers are rotatably sleeved on the two rocker shafts, and the lower edge of the upper joint surface is lower than the two rocker shaft holes. During installation, the rocker shaft can be inserted into the rocker shaft hole from the lower side of the cylinder head, which is convenient for assembly.

[0014] In the above motorcycle engine, the cylinder head has a plurality of fixing parts on the side wall where the higher edge of the upper joint surface is located, and the water pump is fixedly mounted on the plurality of fixing parts, so that the water pump remains stable.

[0015] Compared with the prior art, this motorcycle engine has the following advantages:

[0016] 1. Since the side wall on the higher side of the cylinder head has enough space to open a complete mounting hole for the pump shaft to pass through, and the mounting hole can be concentrically arranged with the camshaft, it is convenient for the camshaft to drive the water pump to operate. By opening a complete mounting hole on the side wall of the cylinder head, the water pump is installed on the cylinder head, and the pump shaft cooperates with the complete mounting hole to ensure the installation stability and sealing at the mounting hole, thereby ensuring the stability of the water pump.

[0017] 2. Since the lower edge of the upper joint surface is lower than the top surface of the valve stem, when the valve clearance needs to be adjusted, the staff can insert the measuring ruler horizontally from the outside to the inside of the lower side of the cylinder body into the valve clearance above the valve to measure the valve clearance width and adjust the valve clearance according to the measurement results, making the valve clearance adjustment more convenient.

[0018] 3. Since the position of the inclined edge of the upper joint surface relative to the adjacent valve stem is lower than the top surface of the adjacent valve stem, the measuring ruler can be directly inserted from the inclined edge of the upper joint surface when adjusting the valve clearance, reducing the insertion length, thereby making the insertion end of the measuring ruler easier to control, further improving the convenience of valve clearance adjustment. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the partial three-dimensional structure of a motorcycle engine.

[0020] Figure 2 This is a top view of the partial structure of a motorcycle engine.

[0021] Figure 3 It is a rear view of the partial structure of a motorcycle engine.

[0022] Figure 4 yes Figure 1 A magnified view of the structure at center.

[0023] Figure 5 yes Figure 2 Structural cross-section view at BB in the middle.

[0024] Figure 6 yes Figure 5 Enlarged view of the structure at C in the middle.

[0025] In the figure, 1. cylinder head; 11. upper joint surface; 12. lower joint surface; 13. chain chamber; 14. camshaft hole; 15. rocker arm shaft hole; 16. intake passage; 17. exhaust passage; 18. mounting hole; 19. fixing part; 2. camshaft; 21. cam; 22. sprocket; 3. valve; 4. rocker arm shaft; 5. water pump; 6. rocker arm; 61. adjusting bolt; 62. roller; 7. valve clearance. DETAILED DESCRIPTION

[0026] The following are specific embodiments of the present invention and the accompanying drawings to further describe the technical solution of the present invention, but the present invention is not limited to these embodiments.

[0027] like Figure 1 , Figure 2 , Figure 3As shown, a motorcycle engine comprises a cylinder head 1, the top surface of the cylinder head 1 is an upper joint surface 11, which is used to cooperate with the cylinder head and fixedly connected, the bottom surface of the cylinder head 1 is a lower joint surface 12, which is used to cooperate with the cylinder body and fixedly connected, a camshaft hole 14 and two rocker shaft holes 15 are opened in the cylinder head 1, the two rocker shaft holes 15 are respectively located on both sides of the camshaft hole 14 and are arranged in parallel, a camshaft 2 is passed through the camshaft hole 14, and a rocker shaft 4 is passed through the rocker shaft hole 15, along the length direction of the camshaft 2, the upper joint surface 11 is inclined relative to the lower joint surface 12, and the angle between the upper joint surface 11 and the lower joint surface 12 is an acute angle, so that The upper joint surface 11 has a higher edge, a lower edge and two inclined edges. The side wall of the cylinder head 1 with the higher edge has a mounting hole 18, and the mounting hole 18 is coaxially arranged with the camshaft hole 14. The side wall of the cylinder head 1 also has a plurality of fixing parts 19 arranged around the mounting hole 18 for installing the water pump 5, that is, the water pump 5 is fixed to the plurality of fixing parts 19 by bolts, and the pump shaft of the water pump 5 can pass through the mounting hole 18 and be fixedly connected to the camshaft 2. The higher edge of the upper joint surface 11 is higher than the camshaft 2, and the height of the higher edge of the upper joint surface 11 is greater than the height of the cam 21 on the camshaft 2 when the peach tip part faces upward. Figure 4 , Figure 5 , Figure 6 As shown, an intake channel 16 and an exhaust channel 17 are respectively provided on both sides where the two inclined edges of the upper joint surface 11 are located. Two valves 3 are also installed on the cylinder head 1. The two valves 3 control the opening and closing of the intake channel 16 and the exhaust channel 17 by sliding up and down. Rocker arms 6 are rotatably sleeved on the two rocker arm shafts 4. One end of the rocker arm 6 is connected to a roller 62, which can abut against the cam 21 of the camshaft 2, and the other end is screwed with an adjusting bolt 61. The lower end face of the adjusting bolt 61 is an arc surface and is opposite to the top end of the valve 3 rod. When the valve 3 is in a closed state and the rocker arm 6 abuts against the cam 21 of the camshaft 2, a valve clearance 7 is formed between the lower end face of the adjusting bolt 61 and the top surface of the valve 3 rod. The lower edge of the upper joint surface 11 is lower than the top surface of the valve 3 rod when the valve 3 is in a closed state, and the lower edge of the upper joint surface 11 is lower than the two rocker arm shaft holes 15.

[0028] The two valves 3 are respectively located on both sides of the camshaft 2, and the upper ends of the two valve 3 rods are respectively close to the two inclined edges of the upper joint surface 11, and the position of the inclined edges of the upper joint surface 11 relative to the adjacent valve 3 rods is lower than the top surface of the adjacent valve 3 rods. The upper ends of the two adjusting bolts 61 and the upper ends of the two valve 3 rods are inclined outward, and the inclination of the adjusting bolts 61 is smaller than the inclination of the valve 3 rods, so that the width of the valve clearance 7 gradually increases from one end to the other end, and the end with the larger width of the valve clearance 7 faces the inclined edge of the upper joint surface 11 adjacent to the valve 3. The cylinder head 1 has a chain cavity 13, and the higher edge of the upper joint surface 11 is located on the side of the chain cavity 13 on the cylinder head 1. A sprocket 22 is also fixed on the camshaft 2, and the sprocket 22 is located in the chain cavity 13, and the higher edge of the upper joint surface 11 is lower than the top of the sprocket 22.

[0029] The specific embodiments described herein are merely examples of the spirit of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in similar ways, but they will not deviate from the spirit of the present invention or exceed the scope defined by the appended claims.

[0030] Although the terms such as cylinder head 1, upper joint surface 11, lower joint surface 12 are used more frequently in this article, the possibility of using other terms is not excluded. These terms are used only to more conveniently describe and explain the essence of the present invention; interpreting them as any additional restrictions is contrary to the spirit of the present invention.

Claims

1. A motorcycle engine, comprising a cylinder head (1), the cylinder head (1) having an upper engaging surface (11) for engaging with a cylinder cover and a lower engaging surface (12) for engaging with a cylinder block, a camshaft (2) and a valve (3) being installed in the cylinder head (1), characterized in that: The coupling surface (11) is arranged obliquely relative to the lower coupling surface (12) along the length direction of the camshaft (2); the higher edge of the upper coupling surface (11) is higher than the camshaft (2); and the cylinder head (1) is provided with a mounting hole (18) coaxially arranged with the camshaft (2) on a side wall where the higher edge of the upper coupling surface (11) is located; the mounting hole (18) is used for the pump shaft of the water pump to pass through, and the camshaft (2) drives the water pump to operate; the lower edge of the upper coupling surface (11) is lower than the top surface of the stem of the valve (3) when the valve (3) is in a closed state; and the cylinder head (1) is provided with a mounting hole (18) coaxially arranged with the camshaft (2) on a side wall where the higher edge of the upper coupling surface (11) is located. A rocker arm (6) is also mounted on the valve body, one end of the rocker arm (6) being capable of abutting against a cam (21) of the camshaft (2), and the other end being threadedly connected with an adjusting bolt (61). When the valve (3) is in a closed state and the rocker arm (6) abuts against the cam (21) of the camshaft (2), a valve clearance (7) is formed between the lower end surface of the adjusting bolt (61) and the top surface of the stem of the valve (3). The width of the valve clearance (7) gradually increases from one end to the other end, and the end with the larger width of the valve clearance (7) faces the inclined edge of the upper joint surface (11) adjacent to the valve (3).

2. The motorcycle engine according to claim 1, characterized in that: There are two valves (3) located respectively on both sides of the camshaft (2), and the upper ends of the stems of the two valves (3) are respectively close to the two inclined edges of the upper joint surface (11), and the position of the inclined edges of the upper joint surface (11) relative to the adjacent valve (3) stems is lower than the top surface of the adjacent valve (3) stems.

3. The motorcycle engine according to claim 2, characterized in that: The lower end of the adjusting bolt (61) is opposite to the top end of the stem of the valve (3).

4. The motorcycle engine according to claim 1, 2 or 3, characterized in that: The height of the higher edge of the upper joint surface (11) is greater than the height of the lobe portion of the cam (21) on the camshaft (2) when it is facing upward.

5. The motorcycle engine according to claim 4, characterized in that: The cylinder head (1) has a chain cavity (13) in it, the higher edge of the upper joint surface (11) is located on the side of the cylinder head (1) where the chain cavity (13) is located, and a sprocket (22) is also fixed to the camshaft (2), the sprocket (22) is located in the chain cavity (13), and the higher edge of the upper joint surface (11) is lower than the top of the sprocket (22).

6. The motorcycle engine according to claim 1, 2 or 3, characterized in that: The angle between the upper joining surface (11) and the lower joining surface (12) is an acute angle.

7. The motorcycle engine according to claim 3, characterized in that: The cylinder head (1) is also provided with two rocker shaft holes (15), and a rocker shaft (4) is fixedly inserted into each of the two rocker shaft holes (15). The two rocker shafts (4) are arranged parallel to the camshaft (2), and the two rocker arms (6) are rotatably sleeved on the two rocker shafts (4), respectively. The lower edge of the upper joint surface (11) is lower than the two rocker shaft holes (15).

8. The motorcycle engine according to claim 1, 2 or 3, characterized in that: The cylinder head (1) has a plurality of fixing parts (19) on a side wall where a higher edge of the upper joint surface (11) is located, and the water pump (5) is fixedly mounted on the plurality of fixing parts (19).

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