Variable valve lift valve mechanism

Abstract

The invention relates to a variable valve lift valve mechanism which comprises a cam assembly arranged on a cam shaft, and the cam assembly comprises a main cam and an auxiliary cam; the rocker arm assembly is arranged on the rocker arm shaft and comprises a main rocker arm linked with the main cam and an auxiliary rocker arm linked with the auxiliary cam; the maximum lift of a main valve lift line type generated by matching of the main cam and the main rocker arm is different from the maximum lift of an auxiliary valve lift line type generated by matching of the auxiliary cam and the auxiliary rocker arm. The valve assembly is connected with the auxiliary rocker arm; the invention discloses a plunger locking assembly. According to the variable valve lift valve mechanism, through collaborative optimization design of the two linear types, a complete buffer section can be provided in the first state of the main valve lift linear type and the second state of the auxiliary valve lift linear type, and it is guaranteed that the complete buffer effect is achieved in the valve opening and closing processes; therefore, the common impact problem in a traditional variable valve mechanism is effectively avoided, and the valve movement is more stable.

Description

Technical Field

[0001] The present invention relates to the technical field of engine valve lift, in particular to a variable valve lift valve timing mechanism. Background Art

[0002] Variable valve lift technology dynamically adjusts the height of the engine's valve opening, ensuring optimal air intake at varying engine speeds. Its core principle involves varying the transmission ratio between the camshaft and valves, or switching between cams with different profiles. This allows for a smaller lift at low speeds to improve fuel economy, while a larger lift at high speeds enhances power output. This technology significantly improves the engine's adaptability to operating conditions, achieving a balance between fuel efficiency and performance.

[0003] In the related art, Chinese patent CN113931712A discloses a rocker arm assembly with variable valve lift, which makes full use of the space at the rocker arm by setting the structure for adjusting the valve lift on the rocker arm, avoiding being restricted by different types of valve bridge assemblies. Moreover, since the transmission method is a "lever" transmission, the cam structure will be fed back to the lift of the valve bridge assembly in a certain proportion after moving a certain distance, and then the position change of the driving member will be fed back to the change of the lift of the valve bridge assembly in a corresponding proportion, so that the valve bridge assembly can achieve a larger lift change in a limited space. Compared with the corresponding relationship between the spatial position adjustment of the adjusting structure and the change of the valve bridge lift height in the variable height valve bridge structure, it has stronger adaptability, saves more space, and responds more quickly during operation, which is conducive to driving and adjusting the lift of the engine valve bridge assembly according to user needs.

[0004] By comparing the above-mentioned existing technologies, the inventors believe that the above-mentioned technical solution mainly realizes the change of valve lift through the gap between the bottom of the piston and the bottom surface of the piston hole. However, since it adopts a single cam design, its cam profile is fixed and can only change the size of the valve lift. Therefore, when the gap distance between the bottom of the piston and the bottom surface of the piston hole is greater than the height of the buffer section of the cam profile, there is a lack of effective buffering at the moment of valve opening and closing, which will generate a large impact force, seriously affecting the reliability and service life of the valve mechanism. Summary of the Invention

[0005] The purpose of the present invention is to provide a variable valve lift valve timing mechanism to solve the problems existing in the prior art.

[0006] In a first aspect, an embodiment of the present application provides a variable valve lift valve timing mechanism, comprising: A cam assembly is provided on the camshaft, wherein the cam assembly includes a main cam and an auxiliary cam; A rocker arm assembly is provided on the rocker arm shaft, the rocker arm assembly comprising a main rocker arm linked to the main cam and a secondary rocker arm linked to the secondary cam; The maximum lift of the main valve lift profile generated by the cooperation of the main cam and the main rocker arm is different from the maximum lift of the auxiliary valve lift profile generated by the cooperation of the auxiliary cam and the auxiliary rocker arm; Valve assembly, connected to auxiliary rocker arm; The plunger locking assembly is provided on the main rocker arm and is used to switch the driving of the valve assembly by the main cam or the auxiliary cam; The variable valve lift valve mechanism includes a first state and a second state; When in the first state, the plunger locking assembly locks the primary rocker arm and the secondary rocker arm, and the primary cam drives the secondary rocker arm through the primary rocker arm, so that the valve assembly moves according to the main valve lift line; When in the second state, the plunger locking assembly releases the lock between the primary rocker arm and the secondary rocker arm, the primary rocker arm and the secondary rocker arm are separated, the main cam idles, and the secondary cam directly drives the valve assembly through the secondary rocker arm, so that the valve assembly moves according to the secondary valve lift line.

[0007] Through the above settings, the engine can provide a complete buffer section under different operating modes, ensuring the buffering effect of the valve opening and closing process, and effectively avoiding impact problems.

[0008] In combination with the first aspect, in one embodiment, the main cam and the auxiliary cam are detachably mounted on the camshaft.

[0009] The above arrangement facilitates subsequent replacement or maintenance of the main cam or auxiliary cam.

[0010] In combination with the first aspect, in one embodiment, the plunger locking assembly includes a plunger member and a piston member, the plunger member can be engaged with or disengaged from the piston member, and the end of the piston member abuts against the auxiliary rocker arm.

[0011] In combination with the first aspect, in one embodiment, the piston member includes a piston chamber opened inside the main rocker arm, the piston chamber is connected to the oil injection channel of the main rocker arm, a piston is provided in the piston chamber, and a piston spring is provided at one end of the piston close to the inside of the piston chamber, and the end of the piston away from the piston spring extends to the outside of the piston chamber and abuts against the secondary rocker arm.

[0012] In combination with the first aspect, in one embodiment, the plunger member includes a plunger cavity opened on the main rocker arm, the plunger cavity is vertically arranged and connected to the piston cavity, a plunger is also provided in the plunger cavity, a plug cover is provided at the end of the plunger cavity, a plunger spring is provided between the plunger and the plug cover, and a locking port adapted for the plunger is also provided on the piston.

[0013] Through the above settings, it is convenient to switch the engine mode under different working conditions.

[0014] In combination with the first aspect, in one embodiment, a limit member is further provided on the auxiliary rocker arm, and the limit member is a first adjusting bolt. A mounting block is integrally provided on the auxiliary rocker arm, and the limit member is threadedly mounted on the mounting block. The end of the piston member abuts against the end of the limit member on the auxiliary rocker arm.

[0015] The above arrangement is used to install a limit piece, and the clearance between the main rocker arm and the valve can be adjusted conveniently through the set limit piece.

[0016] In combination with the first aspect, in one embodiment, a gap adjustment assembly is further provided on the mounting block, and the gap adjustment assembly includes a second adjustment bolt threaded on the mounting block, and an elephant foot is provided at the end of the second adjustment bolt.

[0017] The above arrangement is used to install the second adjusting bolt, which facilitates adjustment of the clearance between the auxiliary rocker arm and the valve, thereby reducing noise and impact caused by improper valve clearance.

[0018] In combination with the first aspect, in one embodiment, the valve assembly includes a valve bridge and a valve guide rod arranged on the bottom surface of the valve bridge, the valve bridge is located at the bottom of the elephant foot, and the valve is arranged at the bottom of the valve guide rod.

[0019] The above arrangement is used to connect the valve.

[0020] In combination with the first aspect, in one embodiment, an anti-fly-off component is further provided on the rocker arm shaft.

[0021] In combination with the first aspect, in one embodiment, the anti-fly-off assembly includes a bracket arranged on the rocker arm shaft, a return spring is provided on the bracket, and the other end of the return spring is connected to the main rocker arm.

[0022] Through the above arrangement, the return spring can overcome the inertia force of the main rocker arm under different working conditions, preventing the main rocker arm from flying off and causing collision between the main rocker arm and the main cam.

[0023] Compared with the prior art, the present invention provides a variable valve lift valve timing mechanism with the following beneficial effects: 1. This variable valve lift valve timing mechanism uses the main cam and primary rocker arm to produce the main valve lift profile, and the secondary cam and secondary rocker arm to produce the secondary valve lift profile. With the coordinated optimization design of the two profiles, a complete buffer section can be provided in the first state of the main valve lift profile and the second state of the secondary valve lift profile, ensuring a complete buffer effect during the valve opening and closing processes. This effectively avoids the impact problem common in traditional variable valve mechanisms, makes valve movement smoother, significantly reduces noise and improves mechanism reliability.

[0024] 2. The variable valve lift valve timing mechanism achieves dynamic optimization of the engine valve lift by dynamically switching between the main valve lift line and the secondary valve lift line. By switching to the second state, the valve can move according to the secondary valve lift line. This line can be designed to match low intake demand conditions, significantly reducing intake pumping losses under low-speed conditions and reducing fuel consumption. By switching to the first state, the valve can move according to the main valve lift line. This line can be designed to match high intake demand conditions, improving intake efficiency at high speeds and enhancing engine power output.

[0025] 3. The variable valve lift valve mechanism can precisely adjust the valve clearance of the main and auxiliary rocker arm mechanisms by setting a limiter and a second adjustment bolt, ensuring that the valves can be accurately opened and closed in different working modes, reducing noise and impact caused by improper valve clearance. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0027] Figure 1 It is an overall schematic diagram of the present invention; Figure 2 This is a side sectional view of the main rocker arm of the present invention; Figure 3 This is a schematic diagram from another perspective of the main cam, auxiliary cam, main rocker arm, auxiliary rocker arm and anti-fly-off assembly of the present invention.

[0028] In the figure: 1. Rocker arm shaft; 2. Camshaft; 3. Main cam; 4. Auxiliary cam; 5. Limiter; 6. Auxiliary rocker arm; 7. Second adjusting bolt; 8. Elephant foot; 9. Valve bridge; 10. Valve guide rod; 11. Main rocker arm; 12. Bracket; 13. Return spring; 14. Piston spring; 15. Piston; 16. Plunger spring; 17. Plunger. DETAILED DESCRIPTION

[0029] In order to enable those skilled in the art to better understand the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0030] Example 1: In this embodiment, the maximum lift of the main valve lift profile is designed to be greater than the maximum lift of the auxiliary valve lift profile. It should be noted that, depending on actual working conditions, the auxiliary lift can also be designed to be greater than the main lift. The relationship between the two does not affect the core concept of the present invention of achieving dual buffer sections through independent cam profiles. At this time, the engine is in the first state. Figure 1 ; A variable valve lift valve mechanism, comprising: A cam assembly is provided on the camshaft 2, the cam assembly comprising a main cam 3 and an auxiliary cam 4, the main cam 3 and the auxiliary cam 4 are connected in series and are detachably mounted on the camshaft 2; In addition, the main cam 3 and the auxiliary cam 4 are detachably mounted on the camshaft 2 by bolts, making it convenient for subsequent staff to maintain or replace them.

[0031] A rocker arm assembly is provided on the rocker arm shaft 1, and the rocker arm assembly includes a main rocker arm 11 linked to the main cam 3 and an auxiliary rocker arm 6 linked to the auxiliary cam 4; Among them, the main rocker arm 11 and the auxiliary rocker arm 6 are connected in series and rotatably mounted on the rocker arm shaft 1; Specifically, the main cam 3 contacts the roller end of the main rocker arm 11, and the auxiliary cam 4 contacts the roller end of the auxiliary rocker arm 6. Under the rotation of the main cam 3 and the auxiliary cam 4, the main rocker arm 11 and the auxiliary rocker arm 6 can be deflected synchronously, thereby realizing the subsequent opening and closing process of the valve.

[0032] In addition, the maximum lift of the main valve lift line generated by the cooperation between the main cam 3 and the main rocker arm 11 is greater than the maximum lift of the auxiliary valve lift line generated by the cooperation between the auxiliary cam 4 and the auxiliary rocker arm 6; The main valve lift profile is generated by the cooperation of the main cam 3 and the main rocker arm 11, and the auxiliary valve lift profile is generated by the cooperation of the auxiliary cam 4 and the auxiliary rocker arm 6. With the help of the coordinated optimization design of the two profiles, a complete buffer section can be provided in the first state of the main valve lift profile and the second state of the auxiliary valve lift profile, ensuring that the valve opening and closing processes have a complete buffer effect, thereby effectively avoiding the impact problem common in traditional variable valve mechanisms, making the valve movement smoother, significantly reducing noise and improving the reliability of the mechanism.

[0033] It should be noted here that the main valve lift profile is jointly determined by the outer contour of the main cam 3 and the rocker arm ratio of the main rocker arm 11, and the auxiliary valve lift profile is jointly determined by the outer contour of the auxiliary cam 4 and the rocker arm ratio of the auxiliary rocker arm 6. Therefore, the outer contours of the main cam 3 and the auxiliary cam 4 of this application can be designed independently, and the two can have the same or different base circle radii, and can also have the same or different top contour line heights. The present invention does not impose any restrictions on the specific contour shapes, base circle sizes and relative heights of the two. The final technical effect of this embodiment is only that the maximum lift of the main valve lift profile generated by the cooperation of the main cam 3 and the main rocker arm 11 is greater than the maximum lift of the auxiliary valve lift profile generated by the cooperation of the auxiliary cam 4 and the auxiliary rocker arm 6.

[0034] In addition, because the outer contours of the main cam 3 and the auxiliary cam 4 of the present application can be designed independently, the present application can adjust the valve opening / closing time by adjusting the phase difference between the cams, thereby achieving timing optimization.

[0035] The valve assembly is connected to the auxiliary rocker arm 6 and is used to open and close the valve.

[0036] The plunger locking assembly is provided on the primary rocker arm 11. The plunger locking assembly includes a plunger member and a piston member. The plunger locking assembly realizes reliable switching of the working modes of the primary cam 3 and the secondary cam 4 through hydraulic control. The end of the piston member abuts against the secondary rocker arm 6. Specifically, if Figure 2 As shown, a limit member 5 is also provided on the auxiliary rocker arm 6, and the limit member 5 is a first adjusting bolt. A mounting block is integrally provided on the auxiliary rocker arm 6, and the limit member 5 is threadedly mounted on the mounting block. The end of the piston member abuts against the end of the limit member 5 on the auxiliary rocker arm 6. The limit member 5 is the power transmission point between the auxiliary rocker arm 6 and the main rocker arm 11.

[0037] See also Figure 2 ,In this embodiment, the plunger locking assembly includes a plunger member and a piston member; Among them, the piston component includes a piston cavity opened inside the main rocker arm 11, a piston 15 is provided in the piston cavity, a piston spring 14 is provided at one end of the piston 15 close to the inside of the piston cavity, and the end of the piston 15 away from the piston spring 14 extends to the outside of the piston cavity and abuts against the end of the limit member 5.

[0038] The piston 15 is slidably connected to the inner wall of the piston cavity, and the piston spring 14 is used to adjust the position of the piston 15. The piston spring 14 is fixed between the piston 15 and the inner wall of the piston cavity; It should be noted that the piston chamber is connected to the oil injection channel of the main rocker arm 11, and the oil injection channel of the main rocker arm 11 is connected to the external solenoid valve through the inclined oil hole of the rocker arm shaft 1. The movement adjustment of the piston 15 can be achieved by controlling the entry of oil through the solenoid valve.

[0039] The plunger component includes a plunger cavity opened on the main rocker arm 11. The plunger cavity and the piston cavity are vertically arranged and connected. A plunger 17 is also provided in the plunger cavity. A plug cover is provided at the end of the plunger cavity. A plunger spring 16 is provided between the plunger 17 and the plug cover. A locking port adapted to the plunger 17 is also provided on the piston 15.

[0040] Among them, the plunger 17 is mainly used to limit the position of the piston 15. The plunger 17 is slidably connected to the inner wall of the plunger cavity. The plunger spring 16 is used to adjust the position of the plunger 17. The plunger spring 16 is fixed between the plunger 17 and the plug cover.

[0041] The plunger locking assembly is hydraulically controlled to switch between different working states. Specifically: In the first state, the control solenoid valve is not energized. At this time, there is no oil pressure in the oil injection channel of the main rocker arm 11. The plunger 17 extends into the locking port of the piston 15 under the action of the plunger spring 16 to achieve connection with the piston 15. At this time, when the main cam 3 drives the main rocker arm 11 to move, the main rocker arm 11 will drive the plunger 17, the plunger 17 drives the piston 15, the piston 15 drives the limiter 5, the limiter 5 drives the auxiliary rocker arm 6, and the auxiliary rocker arm 6 finally drives the valve to work. At this time, the auxiliary cam 4 does not work. The valve works completely according to the main valve lift line of the main cam 3. Under this working condition, the large lift provided by the main valve lift line of the main cam 3 can increase the intake volume by increasing the valve opening amplitude and thus improve the power output of the engine.

[0042] See also Figure 1 and Figure 3 In this embodiment, a gap adjustment assembly is further provided on the mounting block. The gap adjustment assembly includes a second adjustment bolt 7 threaded on the mounting block. The end of the second adjustment bolt 7 is provided with an elephant foot 8.

[0043] Among them, the mounting block is mainly used to install the limiter 5 and the gap adjustment component; Specifically, a nut is provided on the mounting block, and the limiter 5 and the second adjusting bolt 7 are both installed on the mounting block through connecting threads with the nut. By rotating the limiter 5, the distance between its end and the piston 15 can be adjusted, thereby realizing the adjustment of the valve clearance of the main rocker arm 11 and reducing the noise and impact caused by improper valve clearance; and by rotating the second adjusting bolt 7, the distance between its end and the valve assembly can be adjusted, thereby realizing the adjustment of the valve clearance of the auxiliary rocker arm 6 and reducing the noise and impact caused by improper valve clearance.

[0044] like Figure 1 As shown, in this embodiment, the valve assembly includes a valve bridge 9 and a valve guide rod 10 arranged on the bottom surface of the valve bridge 9. The valve bridge 9 is located at the bottom of the elephant foot 8, and the valve is arranged at the bottom of the valve guide rod 10.

[0045] Specifically, by rotating the second adjusting bolt 7, the distance between the elephant foot 8 and the valve bridge 9 can be adjusted, thereby adjusting the gap between the auxiliary rocker arm 6 and the valve, ensuring that the valve can be accurately opened and closed in different working modes, reducing the noise and impact caused by improper valve clearance, extending the service life of the valve mechanism, and improving the performance of the engine under various working conditions.

[0046] In addition, the contact surface between the valve bridge 9 and the valve guide rod 10 is provided with a wear-resistant coating, which is a silicon nitride coating with a thickness of 50-80 μm.

[0047] The silicon nitride coating can reduce the friction coefficient between the valve guide rod 10 and the valve bridge 9, thereby significantly reducing the friction resistance between the valve guide rod 10 and the valve bridge 9, thereby reducing mechanical wear and energy loss and improving the stability of valve opening.

[0048] See also Figure 1 and Figure 3 In this embodiment, an anti-fly-off assembly is also provided on the rocker arm shaft 1, and the anti-fly-off assembly includes a bracket 12 arranged on the rocker arm shaft 1, and a return spring 13 is provided on the bracket 12, and the other end of the return spring 13 is connected to the main rocker arm 11.

[0049] Among them, the material of the return spring 13 in the anti-fly-off assembly is preferably Inconel 718 high-temperature alloy, which can maintain a stable elastic modulus at 400°C, ensuring the reliability of the mechanism under extreme working conditions.

[0050] Specifically, under conditions of high engine speed or rapid deceleration, the main cam 3 and the main rocker arm 11 may be temporarily separated due to inertia or vibration. However, the anti-fly-off component is set up, and the preload force of the return spring 13 is used to always press the main rocker arm 11 toward the main cam 3 to ensure that the two are in close contact, avoiding impact or failure caused by separation, thereby maintaining the dynamic fit between the main rocker arm 11 and the main cam 3, and ensuring precise control of the valve lift. At the same time, the anti-fly-off component can also prevent the main rocker arm 11 from inertial displacement after the hydraulic lock is released, ensuring a smooth transition of the driving stage of the auxiliary cam 4.

[0051] By designing the bracket 12 in conjunction with the return spring 13 , the anti-fly-off function can be achieved by relying solely on mechanical elasticity without the need for a complex control system. This is low-cost and adaptable to high-temperature and high-vibration environments of the engine.

[0052] Example 2: The difference from the first embodiment is that the engine is in the second state at this time; Specifically: Under this working condition, when the control solenoid valve is energized, the engine oil enters the locking port on the piston 15 through the inclined oil hole and the oil injection channel of the rocker arm shaft 1 in turn. Under the action of the engine oil pressure, the plunger 17 overcomes the force of the plunger spring 16 to break away from the locking port of the piston 15 and retract into the plunger cavity. At this time, when the main cam 3 drives the main rocker arm 11 to move, the main rocker arm 11 will drive the plunger 17 to move, but at this time the plunger 17 will no longer drive the piston 15 to move. At this time, although the piston 15 will move with the main rocker arm 11, its During the process, it will be limited by the limit member 5. Under the action of the limit member 5, the piston 15 will retract into the piston chamber. At the same time, the secondary cam 4 drives the secondary rocker arm 6 to move, and then drives the second adjusting bolt 7, elephant foot 8, valve bridge 9 and valve guide rod 10 and valve to work at the same time, thereby realizing the opening and closing of the valve. At this time, the main cam 3 does not work, and the valve works completely according to the secondary valve lift line of the secondary cam 4. Under this working condition, by reducing the opening amplitude of the valve, the intake volume can be reduced, thereby reducing the loss of pumping air and improving fuel economy.

[0053] Example 3: The difference from the first and second embodiments is that the engine is adjusted from the first state to the second state; Specifically, when the control solenoid valve is energized, the engine oil enters the locking port on the piston 15 through the inclined oil hole and the oil injection channel of the rocker arm shaft 1 in turn. Under the action of the engine oil pressure, the plunger 17 overcomes the force of the plunger spring 16 to break away from the locking port of the piston 15 and retract into the plunger cavity. At this time, when the main cam 3 drives the main rocker arm 11 to move, the main rocker arm 11 will drive the plunger 17 to move, but at this time the plunger 17 will no longer drive the piston 15 to move. Although the piston 15 will move with the main rocker arm 11 at this time, it will be limited by the limiter 5 during the movement. Under the action of the limiter 5, the piston 15 will retract into the piston cavity. At the same time, the secondary cam 4 drives the secondary rocker arm 6 to move. Then the second adjusting bolt 7, elephant foot 8, valve bridge 9, valve guide rod 10 and valve are driven in sequence to work simultaneously, thereby realizing the opening and closing of the valve. At this time, the main cam 3 does not work, and the valve works completely according to the auxiliary valve lift line of the auxiliary cam 4. When the control valve is powered off, the oil in the rocker arm shaft 1 is depressurized and quickly released through the solenoid valve, and the plunger 17 will extend into the locking port of the piston 15 under the action of the plunger spring 16 to realize the connection with the piston 15. At this time, when the main cam 3 drives the main rocker arm 11 to move, the valve works completely according to the main valve lift line of the main cam 3, thereby realizing the switching of the engine working state. Conversely, the same applies to the switching of the engine working condition from the second state to the first state.

[0054] The electrical components mentioned in this article are all electrically connected to the main controller and the power supply. The main controller can be a conventional known device that controls a computer, etc., and the existing public power connection technology is not described in detail in this article.

[0055] In the description of this application, it should be noted that the terms "upper" and "lower" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply 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 on this application. Unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" 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 an indirect connection through an intermediate medium, or it can be internal communication between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0056] It should be noted that, in this application, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprising a ..." does not exclude the presence of other identical elements in the process, method, article or device comprising the element.

[0057] The foregoing is merely a list of specific embodiments of the present application, intended to enable those skilled in the art to understand or implement the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application is not limited to the embodiments shown herein, but is intended to conform to the broadest scope consistent with the principles and novel features of the present application.

Claims

1. A variable valve lift valve mechanism, characterized in that: include: A cam assembly arranged on a camshaft (2), the cam assembly comprising a main cam (3) and an auxiliary cam (4); A rocker arm assembly is arranged on the rocker arm shaft (1), the rocker arm assembly comprising a main rocker arm (11) linked to the main cam (3) and an auxiliary rocker arm (6) linked to the auxiliary cam (4); The maximum lift of the main valve lift line generated by the cooperation of the main cam (3) and the main rocker arm (11) is different from the maximum lift of the auxiliary valve lift line generated by the cooperation of the auxiliary cam (4) and the auxiliary rocker arm (6); A valve assembly connected to the auxiliary rocker arm (6); A plunger locking assembly is provided on the main rocker arm (11) and is used to switch the driving of the valve assembly by the main cam (3) or the auxiliary cam (4); The variable valve lift valve mechanism includes a first state and a second state; When in the first state, the plunger locking assembly locks the main rocker arm (11) with the auxiliary rocker arm (6), and the main cam (3) drives the auxiliary rocker arm (6) through the main rocker arm (11), so that the valve assembly moves according to the main valve lift line; When in the second state, the plunger locking assembly releases the locking of the main rocker arm (11) and the auxiliary rocker arm (6), the main rocker arm (11) and the auxiliary rocker arm (6) are separated, the main cam (3) idles, and the auxiliary cam (4) directly drives the valve assembly through the auxiliary rocker arm (6), so that the valve assembly moves according to the auxiliary valve lift line.

2. The variable valve lift valve timing mechanism according to claim 1, characterized in that: The main cam (3) and the auxiliary cam (4) are detachably mounted on the camshaft (2).

3. The variable valve lift valve timing mechanism according to claim 1, characterized in that: The plunger locking assembly includes a plunger member and a piston member. The plunger member can be inserted into or disengaged from the piston member. The end of the piston member abuts against the auxiliary rocker arm.

4. The variable valve lift valve timing mechanism according to claim 3, characterized in that: The piston member includes a piston chamber opened inside the main rocker arm (11), the piston chamber being connected to the oil injection channel of the main rocker arm (11), a piston (15) being provided in the piston chamber, a piston spring (14) being provided at one end of the piston (15) close to the inside of the piston chamber, and an end of the piston (15) away from the piston spring (14) extending to the outside of the piston chamber and abutting against the auxiliary rocker arm (6).

5. The variable valve lift valve timing mechanism according to claim 4, characterized in that: The plunger member comprises a plunger cavity provided on the main rocker arm (11), the plunger cavity being arranged vertically and communicating with the piston cavity, a plunger (17) being provided in the plunger cavity, a plug cover being provided at the end of the plunger cavity, a plunger spring (16) being provided between the plunger (17) and the plug cover, and a locking opening adapted to the plunger (17) being provided on the piston (15).

6. The variable valve lift valve timing mechanism according to claim 4, characterized in that: The auxiliary rocker arm (6) is further provided with a limiting member (5), the limiting member (5) being a first adjusting bolt. A mounting block is integrally provided on the auxiliary rocker arm (6), the limiting member (5) being threadedly mounted on the mounting block, and the end of the piston (15) away from the piston spring (14) abuts against the end of the limiting member (5) of the auxiliary rocker arm (6).

7. The variable valve lift valve timing mechanism according to claim 6, characterized in that: The mounting block is also provided with a gap adjustment assembly, which comprises a second adjustment bolt (7) threaded on the mounting block, and an elephant foot (8) is provided at the end of the second adjustment bolt (7).

8. The variable valve lift valve timing mechanism according to claim 7, characterized in that: The valve assembly comprises a valve bridge (9) and a valve guide rod (10) arranged on the bottom surface of the valve bridge (9); the valve bridge (9) is located at the bottom of the elephant foot (8); and the valve is arranged at the bottom of the valve guide rod (10).

9. The variable valve lift valve timing mechanism according to claim 1, characterized in that: The rocker arm shaft (1) is also provided with an anti-fly-off component.

10. The variable valve lift valve timing mechanism according to claim 9, characterized in that: The anti-fly-off assembly comprises a bracket (12) arranged on the rocker arm shaft (1), a return spring (13) is provided on the bracket (12), and the other end of the return spring (13) is connected to the main rocker arm (11).

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