Variable valve timing system of motorcycle engine

Abstract

The utility model provides a variable valve timing system of a motorcycle engine, and belongs to the technical field of motorcycles. The problem of how to ensure the compact structure of the engine while ensuring normal oil supply and lubrication is solved. According to the variable valve timing system of the motorcycle engine, the motorcycle engine comprises a cylinder head which is provided with an oil supply channel and internally and rotatably connected with a cam shaft, a cavity is formed in the cam shaft, and a plurality of oil outlet holes are formed in the outer wall of the cam shaft in the axial direction; the variable valve timing system comprises a rotor fixed to one end of the cam shaft through a bolt and a shell arranged outside the rotor in a sleeving mode, the bolt is in a rod shape and divides an inner cavity of the cam shaft into an oil conveying cavity and a lubricating cavity in the axial direction, and the oil conveying cavity is communicated with an oil supply channel and an inner cavity of the shell. A flow dividing channel for communicating the oil conveying cavity with the lubricating cavity is formed in the bolt, and the lubricating cavity communicates with the oil outlet holes. The variable valve timing system of the motorcycle engine can ensure that the structure of the engine is compact while normal oil supply and lubrication are ensured.

Description

Technical Field

[0001] The utility model belongs to the technical field of motorcycles and relates to a variable valve timing system of a motorcycle engine. Background Art

[0002] The variable valve timing system is currently a very widely used system in motorcycle engines. Its purpose is to increase the power of the engine. It controls the oil in the engine case to be pumped into the housing of the variable valve timing system through the solenoid valve, thereby pushing the rotor in the housing to drive the camshaft to rotate in the opposite direction to a certain extent, thereby adjusting the intake (exhaust) volume, the opening and closing timing of the valve, and the angle.

[0003] In the prior art, a camshaft is rotatably connected in the cylinder head of a motorcycle engine, and a sprocket is rotatably connected on the camshaft. The variable valve timing system includes a cylindrical outer shell and a rotor that can rotate in the outer shell. The outer shell is fixed to the sprocket by bolts, and the rotor is fixedly connected to the camshaft. At the same time, the sprocket is transmission-connected to the crankshaft in the engine through a chain. As a further specific scheme, an oil passage connected to the housing is axially opened in the camshaft, and an electromagnetic valve for controlling the oil is installed outside the cylinder head of the engine. When working, the crankshaft drives the sprocket to rotate through the chain, and the sprocket drives the outer shell to rotate synchronously. At this time, the outer shell can push the rotor after rotating a certain amplitude, so that the rotor drives the camshaft to rotate synchronously. In this process, the electromagnetic valve controls the oil to enter the oil passage opened on the camshaft, and enters the outer shell of the variable valve timing system through the oil passage, so as to push the rotor in the reverse direction, so that the rotor pushes the camshaft in the reverse direction, thereby achieving the effect of intermittently controlling the valve.

[0004] In addition to the above structure, in order to avoid excessive wear of the camshaft, it is generally necessary to open another lubricating oil channel along the axial direction inside the camshaft, and open multiple lubricating oil holes connected to the lubricating oil channel outside the camshaft. At the same time, a control valve (also a solenoid valve) is installed outside the cylinder head. During the rotation of the camshaft, the oil in the box is pumped into the lubricating oil channel through the control valve, and the oil is thrown out of the lubricating oil hole under the action of the centrifugal force of the rotation of the camshaft, so as to achieve the effect of lubricating the outer wall of the camshaft.

[0005] Although the above structure can ensure the control of the variable valve timing system and the lubrication of the camshaft, it will inevitably make the structure of the engine too complicated, resulting in poor structural compactness of the engine. Summary of the invention

[0006] The purpose of the utility model is to solve the above problems in the prior art and to provide a variable valve timing system for a motorcycle engine. The technical problem to be solved by the utility model is to ensure that the engine structure is compact while ensuring normal oil supply and lubrication.

[0007] The purpose of the utility model can be achieved through the following technical solutions: a variable valve timing system of a motorcycle engine, the motorcycle engine includes a cylinder head with an oil supply channel and a camshaft rotatably connected thereto, the camshaft has a cavity inside and a plurality of oil outlet holes are axially opened on the outer wall, the variable valve timing system includes a rotor fixed to one end of the camshaft by bolts and a shell sleeved outside the rotor, characterized in that the bolt is rod-shaped and divides the cavity in the camshaft axially into an oil delivery cavity and a lubrication cavity, the oil delivery cavity is respectively communicated with the oil supply channel and the cavity in the shell, a shunt channel is opened in the bolt to connect the oil delivery cavity with the lubrication cavity, and the lubrication cavity is communicated with each of the oil outlet holes.

[0008] Compared with the prior art, the variable valve timing system of the motorcycle engine has the following advantages: when the engine is working, the engine oil in the casing is pumped into the oil supply channel and supplied to the cavity in the camshaft through the oil supply channel. In this process, due to the presence of the bolts, the cavity in the camshaft is axially divided into an oil delivery chamber and a lubrication chamber. At the same time, the pumped oil first enters the oil delivery chamber. At this time, the oil first flows into the cavity of the outer shell in the variable valve timing system due to the pressure, so that the outer shell is filled with the oil. After entering the cavity, the oil can push the rotor to drive the camshaft to rotate in the opposite direction by a certain amplitude, thereby realizing the early or delayed opening and closing of the engine valve (it can be an intake valve or an exhaust valve). At the same time, during this process, while ensuring the stable supply of engine oil to the outer shell, the subsequent The oil pressure can input the engine oil into the lubrication chamber of the camshaft through the bypass channel opened on the bolt. At this time, along with the rotation of the camshaft, the engine oil in the lubrication chamber is thrown out from the oil outlet hole under the influence of centrifugal force and adheres to the outer wall of the camshaft. The outer wall of the camshaft is lubricated under the rotation of the camshaft. Through the above structure, the oil circuit for controlling the variable valve timing system and the oil circuit for lubricating the camshaft are connected. After the engine oil is pumped out of the oil supply channel from the housing, the two oil circuits can be supplied with oil in both directions at the same time, which satisfies both the control of the valve and the lubrication of the camshaft. At the same time, there is no need to control the two oil circuits separately through a more complex control system, so as to achieve a compact structure of the engine while ensuring the satisfaction of oil supply and lubrication.

[0009] In the variable valve timing system of the above-mentioned motorcycle engine, a connecting portion is provided on the inner wall of the camshaft along the circumferential direction, the bolt is threadedly connected to the connecting portion, an oil delivery chamber located on one side of the connecting portion is formed between the outer side wall of the bolt and the inner wall of the cavity of the camshaft, a lubrication chamber connected to each of the oil outlet holes is formed in the camshaft on the other side of the connecting portion, and a plurality of oil inlet holes that can connect the oil delivery chamber with the oil supply channel are opened on the outer side wall of the camshaft along the circumferential direction. Specifically, the bolt is connected with the connecting part in the camshaft to press the rotor in the variable valve timing system against one end of the camshaft, and the outer wall of the bolt cooperates with the inner wall of the camshaft cavity to form an oil delivery chamber on one side of the connecting part, and the camshaft is located on the other side of the connecting part as a lubrication chamber. Regarding oil inlet, it is specifically carried out by opening a plurality of circumferentially opened oil inlet holes on the outer wall of the camshaft, and these oil inlet holes are connected with the oil delivery chamber. When the camshaft rotates, these oil inlet holes can be intermittently connected with the lubricating oil channel in turn, so as to achieve the purpose of continuously supplying oil to the oil delivery chamber.

[0010] In the variable valve timing system of the motorcycle engine, the outer wall of the camshaft has a connecting groove that is inwardly recessed along the circumferential direction, and a plurality of the oil inlet holes are provided on the bottom wall of the connecting groove. The existence of the connecting groove can provide a certain buffer for the oil pumped out from the oil supply channel to avoid the oil entering the oil delivery chamber from oscillating. At the same time, the existence of the connecting groove can also increase the contact area between the oil supply channel and each oil inlet hole, thereby achieving the purpose of supplying oil to the oil delivery chamber through multiple oil inlet holes.

[0011] In the variable valve timing system of the motorcycle engine, the cylinder head is provided with a mounting groove, the outlet end of the oil supply channel penetrates the groove wall of the mounting groove, and the camshaft is rotatably connected in the mounting groove so that the outlet end of the oil supply channel is connected to the connecting groove. In this way, the camshaft is radially limited by the mounting groove to ensure its stable assembly, and the pumped gasoline can directly flow out through the outlet end of the oil supply channel penetrating the groove wall of the mounting groove, and is successively input into the oil delivery cavity through the connecting groove and the oil inlet hole during the continuous rotation of the camshaft.

[0012] In the variable valve timing system of the motorcycle engine, the diverter channel includes a radial section opened along the radial direction of the bolt and an axial section opened along the axial direction of the bolt, the radial section is connected to the oil delivery chamber, and the axial section is connected to the lubrication chamber. When the oil is supplied, the oil diverted from the oil delivery chamber can first enter the radial section, then enter the axial section, and finally output to the lubrication chamber. In this process, the oil can impact the inner wall of the axial section when it transitions from the radial section to the axial section, thereby reducing the flow rate of the oil, ensuring that the oil supply in the oil delivery chamber is sufficient, and avoiding excessive oil delivery to the lubrication chamber. At the same time, the oil can also fully unload the kinetic energy previously possessed by the oil during the transition from the radial section to the axial section. After being guided by the inner wall of the axial section, it cooperates with the rotation of the camshaft to ensure that the oil remains in the maximum centrifugal state after entering the lubrication chamber, thereby ensuring that the oil can be quickly output through the oil outlet hole to lubricate the outer wall of the camshaft.

[0013] In the variable valve timing system of the motorcycle engine, the angle formed by the radial section and the axial section is less than or equal to ninety degrees, so as to maximize the effect of the impact action, ensure the oil supply in the lubricating cavity is stable, and ensure that the oil input into the lubricating cavity from the axial section maintains the maximum centrifugal force.

[0014] In the variable valve timing system of the motorcycle engine, the axial section is eccentrically arranged relative to the center line of the bolt. With this arrangement, when the bolt rotates along the camshaft, the motion track formed by the axial section in the annular direction is annular, thereby achieving the effect of increasing the centrifugal force of the engine oil.

[0015] In the variable valve timing system of the motorcycle engine, the camshaft is connected with a plugging cover for sealing the lubricating cavity, thereby preventing the oil input into the lubricating cavity from leaking.

[0016] In the above-mentioned variable valve timing system of the motorcycle engine, there are two camshafts, and the two camshafts are respectively the intake valve control camshaft and the exhaust valve control camshaft, the oil inlet hole of each camshaft is connected to the oil supply channel, and each camshaft is connected to the rotor and the shell sleeved outside the rotor by bolts. As a further solution, the present application can install an additional camshaft on the basis of the original control of the intake valve or the exhaust valve alone, and the two camshafts have the same structure, and the rotor and the shell sleeved outside the rotor are also installed at the end of the camshaft by bolts, and the two camshafts are driven by the chain and the crankshaft, so as to achieve the purpose of controlling the intake valve and the exhaust valve respectively, while taking into account the lubrication of the two camshafts.

[0017] In the variable valve timing system of the motorcycle engine, the outer wall of the cylinder head is also connected with a number of electromagnetic driving parts corresponding to the outer shell, and each electromagnetic driving part corresponds to the position of each outer shell. On the basis of the above scheme, the rotors and the outer shell installed corresponding to the two camshafts are controlled respectively by two electromagnetic driving parts, so as to achieve the purpose of more diversified control methods. The engine can control the intake valve and the exhaust valve through two electromagnetic driving parts in conjunction with two variable valve timing systems according to actual conditions.

[0018] Compared with the prior art, the variable valve timing system of the motorcycle engine has the following advantages:

[0019] 1. The cavity in the camshaft is divided into an oil delivery cavity and a lubrication cavity by bolts. The oil is first input into the oil delivery cavity through the oil inlet hole by the oil supply channel, and the oil is pressed into the housing under the action of subsequent oil pressure, so as to push the rotor and drive the camshaft to rotate in the opposite direction to achieve valve control. At the same time, part of the oil is diverted and input into the lubrication cavity through the diversion channel in the bolts, and is thrown out from the oil outlet holes as the camshaft rotates, so as to lubricate the outer wall of the camshaft, realize two-way oil supply, and reduce redundant control systems, so as to achieve the purpose of compact engine structure.

[0020] 2. By setting the connecting groove, the lubricating oil output from the oil supply channel can be depressurized and buffered, and at the same time, the contact amount with each oil inlet hole is increased to ensure sufficient supply of engine oil.

[0021] 3. By setting the radial section and the axial section, combined with the eccentric setting of the axial section relative to the center line of the bolt, it is ensured that a large centrifugal force can be maintained when the engine oil is input into the lubrication chamber. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a structural schematic diagram of the variable valve timing system of the motorcycle engine.

[0023] Figure 2 It is a cross-sectional view of the variable valve timing system of the motorcycle engine.

[0024] Figure 3 yes Figure 2 A partial enlarged view of point A in the middle.

[0025] Figure 4 It is a cross-sectional view of the variable valve timing system of the motorcycle engine from another perspective.

[0026] Figure 5 yes Figure 4 A partial enlarged view of point B in the middle.

[0027] Figure 6 It is a schematic diagram of the structure in which the bolts and the housing are assembled together.

[0028] Figure 7 It is a structural diagram of the cylinder body.

[0029] Figure 8 It is a schematic diagram of the camshaft structure and a partial enlarged diagram.

[0030] In the figure, 1, cylinder head; 11, oil supply channel; 12, camshaft; 121, oil delivery chamber; 122, lubrication chamber; 123, oil outlet hole; 124, connecting part; 125, oil inlet hole; 126, connecting groove; 127, plugging cover; 13, housing; 14, rotor; 15, mounting groove; 2, electromagnetic drive member; 3, bolt; 31, diverter channel; 311, radial section; 312, axial section. DETAILED DESCRIPTION

[0031] 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.

[0032] like Figure 1 , Figure 2 as well as Figure 4 As shown, in the variable valve timing system of the motorcycle engine, the motorcycle engine includes a cylinder head 1, an oil supply channel 11 connected to the oil pan is opened in the cylinder head 1, and two camshafts 12 arranged in parallel are rotatably connected to the top of the cylinder head 1, one of the camshafts 12 is an intake valve control camshaft for controlling the opening and closing of the engine intake valve, and the other is an exhaust valve control camshaft for controlling the opening and closing of the engine exhaust valve. The two camshafts 12 have cavities inside and are penetrated at both ends. One end of each camshaft 12 is connected to a variable valve timing system, and the variable valve timing system specifically includes a cylindrical shell 13, a rotor 14 that can rotate in the shell 13, and a sprocket is integrally formed on the outer wall of the shell 13 along the circumferential direction. The two shells 13 connect the sprocket to the crankshaft through a chain, thereby driving the variable valve timing system to rotate through the crankshaft.

[0033] Combination Figure 3 and Figure 5 The camshaft 12 has a connecting portion 124 that protrudes inward and is annular along the circumferential direction. The variable valve timing system also includes a rod-shaped bolt 3, which can be a screw as an alternative. It is connected to the connecting portion 124 by screwing, so that the cavity in the camshaft 12 is axially divided into an oil delivery cavity 121 located on one side of the connecting portion 124 and a lubrication cavity 122 located on the other side of the connecting portion 124. At the same time, the bolt 3 presses the rotor 14 in the variable valve timing system to one end of the camshaft 12, so as to ensure the connection reliability of the variable valve timing system.

[0034] Combination Figure 7Specifically, two electromagnetic drive members 2 are installed on the outer wall of the cylinder head 1 corresponding to the two camshafts 12, which are specifically electromagnetic valves. The position of each electromagnetic drive member 2 is opposite to each housing 13. Each electromagnetic drive member 2 is used to pump the oil in the oil pan into the oil supply channel 11. The outlet end of the oil supply channel 11 is arranged on the shaft seat for positioning the camshaft 12 in the cylinder head 1. An annular connecting groove 126 is opened on the outer wall of each camshaft 12 along the circumferential direction, and a plurality of oil inlet holes 125 arranged at intervals and connected to the oil delivery cavity 121 are opened on the bottom wall of each connecting groove 126. A mounting groove 15 is opened in the cylinder head corresponding to the two camshafts 12. The camshaft 12 is rotatably connected in the mounting groove 15 and is opened in the cylinder head. The outlet end of the oil supply channel 11 in the camshaft 11 penetrates the groove wall of the installation groove 15. After the camshaft 11 is installed, it can be connected with the connecting groove 126 opened on the outer wall of the camshaft 11. Under the drive of the electromagnetic driving member 2, the engine oil is pumped into the oil supply channel 11, and then input into the oil delivery chamber 121 through the connecting groove 126 and the oil inlet hole 125. At this time, the engine oil is continuously input into the housing 13 of the variable valve timing system from the oil delivery chamber 121, so that the rotor 14 is pushed by the oil pressure of the engine oil, so that the rotor 14 drives the camshaft 12 to rotate slightly in the opposite direction relative to the crankshaft, thereby achieving the control of the engine intake valve and the engine exhaust valve, ensuring that the timing and angle of opening of each valve are accurately controlled.

[0035] Combination Figure 6 and Figure 8A plurality of oil outlet holes 123 connected to the lubrication chamber 122 are axially provided on the outer wall of the camshaft 12, and a plugging cover 127 for sealing the lubrication chamber 122 is installed at the other end of each camshaft 12. A bypass channel 31 for connecting the oil delivery chamber 121 with the lubrication chamber 122 is provided in the bolt 3. The bypass channel 31 specifically includes a radial section 311 radially provided along the bolt 3 and an axial section 312 axially provided along the bolt 3, wherein the angle formed between the radial section 311 and the axial section 312 is less than or equal to ninety degrees. The solution provided in the embodiment of the present application is that the angle between the two is ninety degrees, and the axial section 312 is eccentrically arranged relative to the center line of the bolt 3, that is, when the oil pressure in the oil delivery chamber 121 is sufficient, part of the engine oil is bypassed and input into the lubrication chamber 122 through the bypass channel 31, and as the camshaft 12 The centrifugal force of the rotation is thrown out by each oil outlet hole 123, so that the engine oil can fully lubricate the outer wall of the camshaft 12, thereby achieving the purpose of reducing the wear of the camshaft 12. In addition, in the actual process, after the engine oil enters the bypass channel 31, when it transitions from the radial section 311 to the axial section 312, the engine oil can continuously impact the inner wall of the radial section 311, thereby slowing down the oil flow rate while fully unloading the kinetic energy in the engine oil, and being continuously pushed forward by the subsequent oil pressure. Due to the eccentric setting of the axial section 312, the centrifugal force of the engine oil can be greatly improved, so that the engine oil can enter the lubrication chamber 122 in a relatively high centrifugal state when it is output from the axial section 312, thereby avoiding the high-speed rotation of the camshaft 12 causing the engine oil to oscillate in the lubrication chamber 122, thereby ensuring the smoothness of the engine oil being thrown out from each oil outlet hole 123.

[0036] 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.

[0037] Although the present invention uses more terms such as cylinder head 1, oil supply channel 11, camshaft 12, oil delivery chamber 121, lubrication chamber 122, oil outlet 123, connection part 124, oil inlet 125, connection groove 126, plug cover 127, housing 13, rotor 14, mounting groove 15, electromagnetic drive member 2, bolt 3, flow diversion channel 31, radial section 311, axial section 312, etc., it does not exclude the possibility of using other terms. 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 variable valve timing system for a motorcycle engine, the motorcycle engine comprising a cylinder head (1) having an oil supply passage (11) and a camshaft (12) rotatably connected thereto, the camshaft (12) having a cavity therein and a plurality of oil outlet holes (123) axially opened on an outer wall thereof, the variable valve timing system comprising a rotor (14) fixed to one end of the camshaft (12) by bolts (3) and a housing (13) sleeved outside the rotor (14), characterized in that: The bolt (3) is rod-shaped and divides the inner cavity of the camshaft (12) along the axial direction to form an oil delivery cavity (121) and a lubrication cavity (122); the oil delivery cavity (121) is respectively connected to the oil supply passage (11) and the inner cavity of the housing (13); a flow dividing passage (31) is provided in the bolt (3) to connect the oil delivery cavity (121) with the lubrication cavity (122); and the lubrication cavity (122) is connected to each of the oil outlet holes (123).

2. The variable valve timing system of a motorcycle engine according to claim 1, characterized in that: The camshaft (12) has a connecting portion (124) on its inner wall along the circumferential direction, the bolt (3) is threadedly connected to the connecting portion (124), an oil delivery chamber (121) located on one side of the connecting portion (124) is formed between the outer wall of the bolt (3) and the inner wall of the cavity of the camshaft (12), a lubrication chamber (122) connected to each of the oil outlet holes (123) is formed in the camshaft (12) on the other side of the connecting portion (124), and a plurality of oil inlet holes (125) capable of connecting the oil delivery chamber (121) with the oil supply channel (11) are formed on the outer wall of the camshaft (12) along the circumferential direction.

3. The variable valve timing system of a motorcycle engine according to claim 2, characterized in that: The outer wall of the camshaft (12) has a connecting groove (126) which is recessed inwardly along the circumferential direction, and the plurality of oil inlet holes (125) are all arranged on the bottom wall of the connecting groove (126).

4. The variable valve timing system of a motorcycle engine according to claim 3, characterized in that: The cylinder head (1) has a mounting groove (15), the outlet end of the oil supply channel (11) penetrates the groove wall of the mounting groove (15), and the camshaft (12) is rotatably connected in the mounting groove (15) to connect the outlet end of the oil supply channel (11) with the connecting groove (126).

5. The variable valve timing system of a motorcycle engine according to claim 2 or 3, characterized in that: The flow diversion channel (31) comprises a radial section (311) opened along the radial direction of the bolt (3) and an axial section (312) opened along the axial direction of the bolt (3); the radial section (311) is connected to the oil delivery chamber (121), and the axial section (312) is connected to the lubrication chamber (122).

6. The variable valve timing system of a motorcycle engine according to claim 5, characterized in that: An angle formed by the radial section (311) and the axial section (312) is less than or equal to ninety degrees.

7. The variable valve timing system of a motorcycle engine according to claim 5, characterized in that: The axial section (312) is eccentrically arranged relative to the center line of the bolt (3).

8. The variable valve timing system of a motorcycle engine according to claim 4, characterized in that: The camshaft (12) is connected to a plugging cover (127) for sealing the lubrication cavity (122).

9. The variable valve timing system of a motorcycle engine according to claim 2 or 3, characterized in that: There are two camshafts (12), and the two camshafts (12) are respectively an intake valve control camshaft and an exhaust valve control camshaft. The oil inlet hole (125) of each camshaft (12) is connected to the oil supply channel (11), and each camshaft (12) is connected to the rotor (14) and a housing (13) sleeved outside the rotor (14) via bolts (3).

10. The variable valve timing system of a motorcycle engine according to claim 9, characterized in that: The outer wall of the cylinder head (1) is also connected to electromagnetic drive components (2) whose number corresponds to the outer shell (13), and the positions of the electromagnetic drive components (2) and the outer shells (13) correspond one to one.

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