Three-valve cylinder head of motorcycle engine

Abstract

The utility model discloses a three-valve cylinder head of a motorcycle engine, which comprises a cylinder head body, two inlet valve mounting channels, an exhaust valve mounting channel and a spark plug assembling channel are arranged in a combustion chamber of the cylinder head body, and the inlet valve mounting channels and the exhaust valve mounting channel are distributed in a triangular shape; a cavity of the combustion chamber is an arc-shaped surface, the top of the combustion chamber is heart-shaped, and the volume of the combustion chamber is 12.2-12.7 ml; the two inlet valve mounting channels are distributed in bilateral symmetry about the center line of the combustion chamber and are Y-shaped, and the end parts of the inlet valve mounting channels are inclined towards one side of the cylinder head body; the center of the exhaust valve installation channel deviates from the center of the combustion chamber by 3-6 mm, the end of the exhaust valve installation channel inclines towards the opposite side of the intake valve installation channel, the spark plug assembly channel is close to one side of the exhaust valve installation channel, the end of the spark plug assembly channel inclines towards one side of the cylinder head body, and the end, located in the combustion chamber, of the spark plug assembly channel is close to the center of the combustion chamber. The distance from the center line of the combustion chamber is 12-16mm.

Description

Technical Field

[0001] The utility model relates to a field, in particular to a three-valve cylinder head of a motorcycle engine. Background Art

[0002] The engine valve mechanism is one of the basic mechanisms of the engine, which mainly includes the valve group (valves, rocker arms and valve springs, etc.) and the valve drive group (camshaft, timing gear, camshaft signal plate, tappets and push rods, etc.). The engine valve mechanism opens and closes the intake and exhaust valves of each cylinder in a timely manner according to the working cycle and ignition sequence requirements in each cylinder of the engine, so that fresh combustible mixture or air can enter the cylinder in time, and exhaust gas can be discharged from the cylinder in time. During the compression and power strokes, the valves are closed to ensure the sealing of the combustion chamber.

[0003] At present, the valve train of motorcycle engines mainly has two valves or four valves. The charging efficiency of the two-valve engine is not high. Although the four-valve engine has good charging efficiency, its cost is relatively high. Based on this, the three-valve structure engine is widely used. The cylinder head of the engine with this structure has two intake valve installation channels and one exhaust valve installation channel. The intake valve installation channels and the exhaust valve installation channels are distributed in a triangular shape, and the center of the exhaust channel overlaps with the center of the combustion chamber. The spark plug installation channel is located between the intake valve installation channels (such as Figure 1 As shown). After the spark plug is installed, one of the intake valves is farther away from the spark plug, so it is easy to fail during ignition. It is difficult to ignite at one time under extreme conditions (poor oil-gas mixing). At the same time, the combustion efficiency in the existing combustion chamber is not high. Summary of the invention

[0004] In view of the above-mentioned deficiencies in the prior art, the purpose of the utility model is to provide a three-valve cylinder head for a motorcycle engine, so as to solve the problem that the spark plug hole in the three-valve cylinder head of the existing motorcycle engine is far away from the center and ignition cannot be achieved in one go under extreme conditions.

[0005] In order to solve the above technical problems, the utility model adopts the following technical solutions:

[0006] A three-valve cylinder head for a motorcycle engine comprises a cylinder head body, wherein two intake valve mounting channels, an exhaust valve mounting channel and a spark plug mounting channel are arranged in a combustion chamber of the cylinder head body, and the intake valve mounting channels and the exhaust valve mounting channels are arranged in a triangular shape; the chamber of the combustion chamber is an arc-shaped surface, the top is heart-shaped, and the volume of the combustion chamber is 12.2-12.7ml; the two intake valve mounting channels are arranged symmetrically about the center line of the combustion chamber, in a Y shape, and the ends are inclined toward one side of the cylinder head body; the center of the exhaust valve mounting channel deviates from the center of the combustion chamber by 3-6mm, and the end is inclined toward the opposite side of the intake valve mounting channel, the spark plug mounting channel is adjacent to one side of the exhaust valve mounting channel, and the end is inclined toward one side of the cylinder head body, and the spark plug mounting channel is located at one end of the combustion chamber, close to the center of the combustion chamber, and 12-16mm away from the center line of the combustion chamber. In this way, after the exhaust valve mounting channel is eccentrically set, the spark plug mounting channel can be closer to the center of the combustion chamber (i.e., the center of the cylinder head body), so that the spark plug is adjacent to the center of the combustion chamber after installation, which is more convenient for ignition and combustion, and improves the combustion rate of the gas. After the intake valve mounting channel, the exhaust valve mounting channel and the spark plug mounting channel are tilted, the layout between the intake duct, the exhaust duct and the spark plug in the combustion chamber is more compact, ensuring that the valve seat ring and the spark plug hole do not interfere directly. At the same time, there is sufficient wall thickness between the spark plug mounting channel and the exhaust valve mounting channel, which is not easy to deform after long-term use. The two intake valve mounting channels are Y-shaped and the exhaust valve mounting channel is eccentrically set, which is conducive to improving the intake and exhaust efficiency and improving the engine performance. The combustion chamber is set in a heart-shaped structure, which is conducive to improving the combustion efficiency of the mixture.

[0007] Further, the spacing between the centers of the two intake valve installation passages is 25-27 mm. In this way, the intake valve installation passage center distance is suitable, which is conducive to adopting an intake valve seat ring with a larger thickness to ensure the valve seat ring strength.

[0008] Furthermore, a valve drive assembly chamber is provided in the cylinder head body and on the opposite side of the combustion chamber, and the valve drive assembly chamber includes a sprocket assembly chamber and a cam rocker arm installation chamber that are interconnected. A camshaft hole and two rocker arm shaft holes are provided on both sides of the cam rocker arm installation chamber, wherein two rocker arm shaft holes overlapping in the center form an intake valve rocker arm shaft assembly position, and the other two rocker arm shaft holes form an exhaust valve rocker arm shaft assembly position; each rocker arm shaft hole protrudes 1-2mm toward one side of the cam rocker arm installation chamber. In this way, the rocker arm shaft hole in the cylinder head body protrudes inward, and the protrusion length is small, which can ensure the stability of the intake valve rocker arm shaft and the exhaust valve rocker arm shaft after installation, ensure that the rocker arm shaft will not be cantilevered after installation, and will not generate large noise due to poor cantilever support, and prevent the occurrence of cantilever structure and noise.

[0009] Furthermore, an air duct is provided between the valve train assembly chamber and the combustion chamber, and a reinforcing rib is provided in the air duct. Thus, after the reinforcing rib is provided in the air duct, the air duct is close to the camshaft hole, which is helpful to resist the deformation of the camshaft hole in the valve train assembly chamber, thereby achieving the purpose of reducing noise.

[0010] Furthermore, the intake valve mounting channel and the exhaust valve mounting channel are both equipped with a seat ring at one end close to the combustion chamber, and the seat ring of the intake valve mounting channel and the seat ring of the exhaust valve mounting channel have an angle of 135-137 degrees. This angle can ensure that the combustion chamber volume is designed to be 12.2-12.7ml, and at the same time can ensure that the intake and exhaust valves are arranged more compactly, and the intake and exhaust valves will not interfere with each other during movement. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a schematic diagram of the three-valve valve mechanism of a motorcycle engine in the prior art;

[0012] Figure 2 Schematic diagram of a three-valve cylinder head of a motorcycle engine in the embodiment Figure 1 ;

[0013] Figure 3 Schematic diagram of a three-valve cylinder head of a motorcycle engine in the embodiment Figure 2 ;

[0014] Figure 4 Schematic diagram of a three-valve cylinder head of a motorcycle engine in the embodiment Figure 3 ;

[0015] Figure 5 for Figure 3 Schematic diagram of the cross-sectional structure of the middle BB;

[0016] Figure 6 for Figure 4 Schematic diagram of the cross-sectional structure of the CC;

[0017] Figure 7 for Figure 3 Schematic diagram of the cross-sectional structure of DD. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical scheme and advantages of the embodiment of the utility model clearer, the technical scheme in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is a part of the embodiment of the utility model, not all of the embodiments. The components of the embodiment of the utility model generally described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiment of the utility model provided in the drawings is not intended to limit the scope of the utility model claimed for protection, but merely represents the selected embodiment of the utility model. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without making creative work belong to the scope of protection of the utility model.

[0019] It should be noted that similar numbers and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings. In the description of the utility model, it should be noted that the orientation or position relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. is based on the orientation or position relationship shown in the drawings, or the orientation or position relationship in which the invention product is usually placed when used, which is only for the convenience of describing the utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the utility model. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance. In addition, the terms "horizontal", "vertical", etc. do not mean that the components are absolutely horizontal or suspended, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted. In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0020] like Figure 2-Figure 7As shown, the three-valve cylinder head of a motorcycle engine provided in this embodiment comprises a cylinder head body 1, in which two intake valve mounting channels 3, an exhaust valve mounting channel 4 and a spark plug mounting channel 5 are arranged in a combustion chamber 2 of the cylinder head body 1, and the intake valve mounting channels 3 and the exhaust valve mounting channels 4 are distributed in a triangular shape; the chamber of the combustion chamber 2 is an arc-shaped surface, the top is heart-shaped, and the volume of the combustion chamber 2 is 12.2-12.7ml; the two intake valve mounting channels 3 are symmetrically distributed about the center line of the combustion chamber 2, in a Y shape, and the ends are inclined toward one side of the cylinder head body 1; the center of the exhaust valve mounting channel 4 deviates from the center of the combustion chamber 2 by 4mm, and the end is inclined toward the opposite side of the intake valve mounting channel 3, the spark plug mounting channel 5 is adjacent to one side of the exhaust valve mounting channel 4, and the end is inclined toward one side of the cylinder head body 1, and the spark plug mounting channel 5 is located at one end of the combustion chamber 2, close to the center of the combustion chamber 2, and 14mm away from the center line of the combustion chamber 2. In this way, after the exhaust valve mounting channel 4 is eccentrically set, the spark plug mounting channel 5 can be closer to the center of the combustion chamber 2 (i.e., the center of the cylinder head body 1), so that the spark plug is adjacent to the center of the combustion chamber 2 after installation, which is more convenient for ignition and combustion, and improves the combustion rate of the gas. After the intake valve mounting channel 3, the exhaust valve mounting channel 4 and the spark plug mounting channel 5 are tilted, the layout between the intake duct, the exhaust duct and the spark plug in the combustion chamber 2 is more compact, ensuring that the valve seat ring and the spark plug hole do not interfere directly. At the same time, there is enough wall thickness between the spark plug mounting channel 5 and the exhaust valve mounting channel 4, which is not easy to deform after long-term use. The two intake valve mounting channels 3 are Y-shaped and the exhaust valve mounting channel 4 is eccentrically set, which is conducive to improving the intake and exhaust efficiency and improving the engine performance. The combustion chamber 2 is set in a heart-shaped structure, which is conducive to improving the combustion efficiency of the mixture.

[0021] Further, the spacing between the centers of the two intake valve installation passages 3 is 26 mm. In this way, the center distance of the intake valve installation passage 3 is suitable, which is conducive to adopting an intake valve seat ring with a larger thickness to ensure the strength of the valve seat ring.

[0022] Furthermore, a valve drive assembly chamber is provided in the cylinder head body 1 on the opposite side of the combustion chamber 2, and the valve drive assembly chamber includes a sprocket assembly chamber 7 and a cam rocker arm installation chamber 6 that are interconnected. A camshaft hole 8 and two rocker arm shaft holes 9 are provided on both sides of the cam rocker arm installation chamber 6, wherein two rocker arm shaft holes 9 with overlapping centers form an intake valve rocker arm shaft assembly position, and the other two rocker arm shaft holes 9 form an exhaust valve rocker arm shaft assembly position; each rocker arm shaft hole 9 protrudes 1.5 mm toward one side of the cam rocker arm installation chamber 6. In this way, the rocker arm shaft hole 9 in the cylinder head body 1 protrudes inward, and the protrusion length is small, which can ensure the stability of the intake valve rocker arm shaft and the exhaust valve rocker arm shaft after installation, ensure that the rocker arm shaft will not be cantilevered after installation, and will not generate large noise due to poor cantilever support, and prevent the occurrence of cantilever structure to generate noise.

[0023] Furthermore, an air duct is provided between the valve train assembly chamber and the combustion chamber 2, and a reinforcing rib 10 is provided in the air duct (the reinforcing rib is located below the camshaft hole). Thus, after the reinforcing rib 10 is provided in the air duct, the air duct is close to the camshaft hole 8, which is helpful to resist the deformation of the camshaft hole 8 in the valve train assembly chamber, so as to achieve the purpose of reducing noise.

[0024] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the utility model rather than to limit the technical solution. Ordinary technicians in this field should understand that those modifications or equivalent replacements of the technical solution of the utility model without departing from the purpose and scope of the technical solution of the utility model should be included in the scope of the claims of the utility model.

Claims

1. A three-valve cylinder head for a motorcycle engine, comprising a cylinder head body, wherein two intake valve mounting channels, one exhaust valve mounting channel and one spark plug mounting channel are arranged in a combustion chamber of the cylinder head body, wherein the intake valve mounting channels and the exhaust valve mounting channels are distributed in a triangular shape; characterized in that: The chamber of the combustion chamber is an arc-shaped surface with a heart-shaped top, and the volume of the combustion chamber is 12.2-12.7ml; the two intake valve mounting channels are symmetrically distributed about the center line of the combustion chamber, in a Y shape, and the ends are inclined toward one side of the cylinder head body; the center of the exhaust valve mounting channel deviates from the center of the combustion chamber by 3-6mm, and the end is inclined toward the opposite side of the intake valve mounting channel. The spark plug mounting channel is adjacent to one side of the exhaust valve mounting channel, and the end is inclined toward the side of the cylinder head body. The spark plug mounting channel is located at one end of the combustion chamber, close to the center of the combustion chamber, and 12-16mm away from the center line of the combustion chamber.

2. The three-valve cylinder head of a motorcycle engine according to claim 1, characterized in that: The distance between the centers of the two intake valve mounting channels is 25-27 mm.

3. The three-valve cylinder head of a motorcycle engine according to claim 1 or 2, characterized in that: A valve transmission group assembly chamber is also provided in the cylinder head body, on the opposite side of the combustion chamber, and the valve transmission group assembly chamber includes a sprocket assembly chamber and a cam rocker arm installation chamber which are interconnected. A camshaft hole and two rocker arm shaft holes are provided on the left and right sides of the cam rocker arm installation chamber, wherein two center-overlapping rocker arm shaft holes form an intake valve rocker arm shaft assembly position, and the other two rocker arm shaft holes form an exhaust valve rocker arm shaft assembly position; each rocker arm shaft hole protrudes 1-2 mm toward one side of the cam rocker arm installation chamber.

4. The three-valve cylinder head of a motorcycle engine according to claim 3, characterized in that: An air duct is also arranged between the valve transmission assembly chamber and the combustion chamber, and a reinforcing rib is arranged in the air duct.

5. The three-valve cylinder head of a motorcycle engine according to claim 1, 2 or 4, characterized in that: The intake valve mounting channel and the exhaust valve mounting channel are both equipped with a seat ring at one end close to the combustion chamber, and there is an angle of 135-137° between the seat ring of the intake valve mounting channel and the seat ring of the exhaust valve mounting channel.

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