Variable valve timing and valve lift device and engine

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By designing variable gas distribution phase and valve lift devices in gasoline engines, the problem of fixed and immutable valve lift of traditional engines is solved, and the optimal valve lift and phase in high-speed and low-speed periods are achieved, which improves engine efficiency and power output, and reduce wear and extend service life.

CN222457540UActive Publication Date: 2025-02-11LONCIN MOTOR CO LTD +2

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Patent Information

Application Number: CN202421117655.2
Authority / Receiving Office: CN · China
Patent Type: Utility models(China)
Current Assignee / Owner
Filing Date: 2024-05-21
Publication Date: 2025-02-11
Estimated Expiration: 2034-05-21

AI Technical Summary

Technical Problem

The valve lift of traditional gasoline engines is fixed and immutable, resulting in the inability to get the best response when driving at high speed and low speed, which in turn affects the efficiency and power output of the engine. At the same time, the uneven moment of inertia of the low-speed intake rocker arm leads to valves and adjustment bolts. wear.

Method used

Design a variable air distribution phase and valve lift device, by setting a low-speed and high-speed intake cam on the camshaft, and setting a corresponding low-speed intake rocker and high-speed intake arm on the rocker shaft, use lift The adjustment components and limit preload force achieve variability in valve lift, ensuring that the valve lift and phase can be obtained at both high and low speed periods, while balancing the moment of inertia of the low-speed intake rocker arm.

Benefits of technology

It realizes that the engine can meet the valve lift and phase in both the high-speed and low-speed zones, improves the high-speed power and low-speed torque of the engine, reduces fuel consumption and improves emissions, and reduces wear of valves and adjustment bolts, extends service life.

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Patent Text Reader

Abstract

The utility model discloses a variable valve timing and valve lift device and an engine, and the variable valve timing and valve lift device comprises a cam shaft, a rocker arm shaft and a lift adjusting assembly, a low-speed air inlet rocker arm and a high-speed air inlet arm which are matched with the low-speed air inlet cam and the high-speed air inlet cam respectively are arranged on the rocker arm shaft; the lift adjusting assembly comprises a first connecting base fixed to a low-speed air inlet rocker arm and a second connecting base fixed to a high-speed air inlet rocker arm. The first connecting base and the second connecting base are arranged over a rocker arm shaft or on the side, close to a cam shaft, of the upper portion of the rocker arm shaft, and the first connecting base and the second connecting base can be operated to be synchronously connected or disconnected. According to the low-speed air inlet rocker arm, an engine can obtain valve lift and phase meeting requirements at a high speed and a low speed, high-speed power and low-speed torque of the engine are improved, balanced distribution of rotational inertia of the low-speed air inlet rocker arm is guaranteed, abrasion to an air inlet valve when the low-speed air inlet rocker arm swings is reduced, and the service life is prolonged.

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Description

Technical Field

[0001] The utility model relates to the technical field of engines, in particular to a variable valve timing and valve lift device and an engine. Background Art

[0002] The valve lift of a traditional gasoline engine is fixed and cannot be changed, that is, there is only one cam profile of the camshaft. The cam profile design is a balanced choice for the engine under all working conditions. This results in the fixed and unchangeable lift not being able to make the engine respond well at both high and low speeds. As a result, the engine can neither obtain the best high-speed efficiency nor the best low-speed torque. Therefore, through the engine technology of variable valve lift, the engine can adjust the valve stroke size according to different working conditions. This technology can provide sufficient power and reduce fuel consumption by reducing the valve stroke at low speeds, and can further improve the engine's intake efficiency and thus enhance power output by increasing the valve stroke at medium and high speeds.

[0003] In the prior art, a high-speed intake cam and a low-speed intake cam are arranged on the camshaft, and a high-speed intake arm and a low-speed intake rocker arm are arranged on the rocker arm shaft accordingly. The connection and disconnection of the high-speed intake arm and the low-speed intake rocker arm are controlled by a switching pin, so that the best high-speed power and the best low-speed torque can be obtained at high speed and low speed respectively. A connecting seat for the switching pin to extend into is arranged on the high-speed intake arm and the low-speed intake rocker arm. The connecting seat is generally arranged on the side close to the valve, which will cause uneven weight distribution on the rocker arm and unbalanced moment of inertia of the rocker arm. During the closing process of the intake valve, the connection seat is arranged close to the valve group, which will cause the weight of the connection seat to be loaded on the intake valve. At this time, the intake valve needs a greater force to push the rocker arm to close the intake valve, which makes the adjusting bolt and the valve end face more easily worn.

[0004] Therefore, it is urgent to develop a variable valve timing and valve lift device that can ensure that the engine can obtain the required valve lift and phase in both high-speed and low-speed zones, while avoiding the wear of the valve and adjusting bolt due to uneven distribution of rotational inertia of the low-speed intake rocker arm. Utility Model Content

[0005] In view of this, the purpose of the utility model is to provide a variable valve timing and valve lift device and an engine, which can ensure that the engine can obtain the valve lift and phase that meet the requirements in both high-speed and low-speed areas, improve the engine's high-speed power and low-speed torque, effectively reduce fuel consumption and improve emissions, and ensure that the rotational inertia of the high-speed intake arm and the low-speed intake rocker arm is evenly distributed, reduce the wear of the high-speed intake arm and the low-speed intake rocker arm on the valve, and extend the service life.

[0006] The utility model provides a variable valve timing and valve lift device, including a camshaft, a rocker shaft and a lift adjustment component, the camshaft is provided with a low-speed intake cam and a high-speed intake cam, the rocker shaft is provided with a low-speed intake rocker arm and a high-speed intake arm respectively matched with the low-speed intake cam and the high-speed intake cam; the lift adjustment component includes a first connecting seat fixed to the low-speed intake rocker arm and a second connecting seat fixed to the high-speed intake arm, the first connecting seat and the second connecting seat are arranged directly above the rocker shaft or on the upper side close to the camshaft, and the first connecting seat and the second connecting seat can be operated to be connected synchronously or disconnected.

[0007] Furthermore, the lift adjustment assembly also includes an adjustment pin shaft, and the first connecting seat and the second connecting seat are respectively provided with pin holes. The adjustment pin shaft can be operated to simultaneously penetrate the pin holes of the first connecting seat and the second connecting seat to form the synchronous connection, or can be operated to pull out at least one pin hole to form the disconnection.

[0008] Furthermore, the high-speed intake arm is applied with a limiting preload force that always keeps in contact with the high-speed intake cam.

[0009] Furthermore, the limiting preload force is applied by a torsion spring arranged on the rocker arm shaft.

[0010] Furthermore, the adjusting pin is provided with a disconnecting preload, and the preload has a tendency to drive the adjusting pin to disconnect the first connecting seat and the second connecting seat. The lift adjustment assembly also includes a pushing pin, and the pushing pin can be operated to push the adjusting pin to overcome the disconnecting preload so that the first connecting seat and the second connecting seat are connected synchronously.

[0011] Furthermore, the disconnection preload force is applied by a spring arranged in the pin hole of the first connecting seat.

[0012] Furthermore, the adjusting pin is arranged in the pin hole of the first connecting seat, and a spring for applying a disconnection preload force is arranged in the pin hole of the first connecting seat, one end of the spring presses on the adjusting pin, and the other end presses on the inner wall of the pin hole.

[0013] Furthermore, the end of the push pin is provided with an end head, and the end head of the push pin can cover the moving trajectory of the adjustment pin shaft as the low-speed intake rocker arm and the high-speed intake arm swing, and the adjustment pin shaft deviates from the axis center of the push pin end head and is connected to the push pin end head.

[0014] Furthermore, an exhaust cam is also provided on the camshaft, and a decompression member and a centrifugal member for driving the decompression member are provided next to the exhaust cam. When the engine is started, the decompression member acts on the exhaust rocker arm to open the exhaust valve. After the engine is started, under the action of the centrifugal member, the decompression member is separated from the exhaust rocker arm.

[0015] The utility model also provides an engine, on which the variable valve timing and valve lift device mentioned above is installed.

[0016] The beneficial effects of the utility model: the variable valve timing and valve lift device of the utility model can ensure that the engine can obtain the valve lift and phase that meet the requirements in both the high-speed zone and the low-speed zone, improve the high-speed power and low-speed torque of the engine, effectively reduce fuel consumption and improve emissions. At the same time, the first connecting seat and the second connecting seat are arranged directly above the rocker arm shaft or on the side above the camshaft, which can evenly distribute the rotational inertia on the low-speed intake rocker arm, reduce the wear of the low-speed intake rocker arm on the intake valve when it swings, and extend the service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The utility model is further described below in conjunction with the accompanying drawings and embodiments:

[0018] Figure 1 It is a structural schematic diagram of the utility model;

[0019] Figure 2 It is a front view of the utility model;

[0020] Figure 3 It is a cross-sectional view of a low-speed intake rocker arm and a high-speed intake arm;

[0021] Figure 4 The diagram is a swing diagram of the low-speed intake rocker arm;

[0022] Figure 5 It is a top view of the utility model;

[0023] Figure 6 It is a side view of the utility model;

[0024] Figure 7 Schematic diagram of the camshaft structure.

[0025] Numbers in the figure: 1. camshaft; 2. rocker arm shaft; 3. low-speed intake cam; 4. high-speed intake cam; 5. low-speed intake rocker arm; 6. high-speed intake arm; 7. first connecting seat; 8. second connecting seat; 9. intake valve; 10. adjusting bolt; 11. adjusting pin shaft; 12. pin hole; 13. solenoid valve; 14. torsion spring; 15. mounting seat; 16. cylindrical pin; 17. push pin; 18. spring; 19. compression end face; 20. end; 21. exhaust cam; 22. exhaust rocker arm; 23. exhaust valve; 24; timing driven wheel. DETAILED DESCRIPTION

[0026] Figure 11 is a schematic diagram of the structure of the utility model. As shown in the figure, the utility model provides a variable valve timing and valve lift device, including a camshaft 1, a rocker shaft 2 and a lift adjustment component. The camshaft 1 is provided with a low-speed intake cam 3 and a high-speed intake cam 4. The rocker shaft 2 is provided with a low-speed intake rocker arm 5 and a high-speed intake arm 6 respectively matched with the low-speed intake cam 3 and the high-speed intake cam 4; the lift adjustment component includes a first connecting seat 7 fixed to the low-speed intake rocker arm 5 and a second connecting seat 8 fixed to the high-speed intake arm 6. The first connecting seat 7 and the second connecting seat 8 are arranged directly above the rocker shaft 2 or on the side close to the camshaft 1 above, and the first connecting seat 7 and the second connecting seat 8 can be connected synchronously or disconnected by operation; because the profile of the high-speed intake cam includes a low The low-speed intake cam has a profile line, and the cam lobe angle and the cam maximum lift are different, so as to realize variable valve timing and valve lift; during the operation of the engine, the low-speed intake rocker arm 5 and the high-speed intake arm 6 will rotate around the rocker arm shaft, and the first connecting seat 7 and the second connecting seat 8 are arranged just above the rocker arm shaft 2 or above and close to the camshaft 1, so as to balance the rotational inertia of the low-speed intake rocker arm 5 and the high-speed intake arm 6. During the closing process of the intake valve 9, the weight load of the first connecting seat 7 and the second connecting seat 8 on the intake valve 9 is reduced, and the force required for the intake valve 9 to push the low-speed intake rocker arm 5 is reduced, so as to more effectively close the intake valve 9, and avoid the first connecting seat 7 and the second connecting seat 8 being too close to the intake valve 9, thereby increasing the load of the intake valve 9 and causing wear of the adjusting bolt 10 and the intake valve 9.

[0027] In this embodiment, the lift adjustment component also includes an adjusting pin 11, and the first connecting seat 7 and the second connecting seat 8 are respectively provided with pin holes 12. The adjusting pin 11 can be operated to simultaneously penetrate the pin holes 12 of the first connecting seat 7 and the second connecting seat 8 to form the connection synchronization, or can be operated to pull out at least one pin hole 12 to form the disconnection; the adjusting pin 11 can be operated to simultaneously penetrate the pin holes of the first connecting seat 7 and the second connecting seat 8 so that the first connecting seat 7 and the second connecting seat 8 form the connection synchronization, and the adjusting pin 11 can be operated to pull out the pin holes 12 of the first connecting seat 7 and / or the second connecting seat 8 to form the disconnection; the adjusting pin 11 is driven by a solenoid valve 13, and the adjusting pin 11 can also be operated by electric drive, hydraulic drive, pneumatic drive or spring drive, etc., which will not be repeated here.

[0028] In the present embodiment, a limiting preload force is applied to the high-speed intake arm 6 so as to always keep in contact with the high-speed intake cam 4; the limiting preload force can be applied to the high-speed intake arm 6 by setting a torsion spring 14 on the rocker shaft 2, or can be set on other parts of the engine or on the chassis to apply the limiting preload force to the high-speed intake arm 6. For example, a compression spring is set directly above the high-speed intake arm 6 or in other directions, one end of the compression spring is pressed against the inner wall of the chassis, and the other end acts on the high-speed intake arm 6, which can apply a limiting preload force to the high-speed intake arm 6 so as to always keep in contact with the high-speed intake cam.

[0029] In this embodiment, the limiting preload force is applied by a torsion spring 14 arranged on the rocker arm shaft 2; compared with other methods of applying a limiting preload force to the high-speed intake arm 6, the limiting effect of setting a torsion spring 14 on the rocker arm shaft 2 is better and easier to assemble, and occupies less space inside the engine. Therefore, it is preferred to set a torsion spring on the rocker arm shaft 2 to apply a limiting preload force to the high-speed intake arm 6.

[0030] In this embodiment, Figure 1 As shown, the torsion spring 14 is placed next to the high-speed air intake arm 6 through a mounting seat 15. The high-speed air intake arm 6 is provided with a cylindrical pin 16 on the side close to the torsion spring 14. When the high-speed air intake arm 6 rotates around the rocker arm shaft 2, one end of the torsion spring 14 can abut against the cylindrical pin 16 to limit the high-speed air intake arm 6, and the other end of the torsion spring 14 abuts against the mounting seat 15.

[0031] In this embodiment, Figure 1As shown, the side of the high-speed intake arm 6 close to the intake valve 9 cannot directly act on the intake valve 9. The low-speed intake rocker arm 5 and the high-speed intake arm 6 must be connected and synchronized through the lift adjustment component before the high-speed intake arm 6 can transmit the lift of the high-speed intake cam 4 to the intake valve 9. When the engine is running at a low speed, the high-speed intake arm 6 idles around the rocker arm shaft 2. If the high-speed intake arm 6 is not limited, when the high-speed intake arm 6 is lifted to the maximum lift by the high-speed intake cam 4, the high-speed intake arm 6 will return to the lowest lift under the action of inertia and will not be lifted by the high-speed intake cam 4. In the process of returning to the lowest lift, the high-speed intake arm 6 will cause a large impact on the high-speed intake cam 4 and the camshaft 1, and the engine The safe use of the engine will be affected, and the service life of the camshaft 1 and the high-speed intake cam 4 will be reduced; applying a limit preload force to the high-speed intake arm 6 to keep it in contact with the high-speed intake cam 4 at all times can prevent the high-speed intake arm 6 from separating from the high-speed intake cam 4 and causing impact on the high-speed intake cam 4 and the camshaft 1 under the action of inertia; in the process of the high-speed intake arm 6 and the low-speed intake rocker arm 5 rotating around the rocker arm shaft 2, the limit preload force can also ensure that the pin holes 12 on the first connecting seat 7 and the second connecting seat 8 always remain opposite (facing when the cam base circle, i.e., the cam lift is zero). When the engine needs to switch to low speed or high speed, it can ensure that the first connecting seat 7 and the second connecting seat 8 can be operated to be connected synchronously or disconnected.

[0032] In this embodiment, the adjusting pin 11 is provided with a disconnection preload, and the preload has a tendency to drive the adjusting pin 11 to disconnect the first connecting seat 7 and the second connecting seat 8. The lift adjustment assembly also includes a pushing pin 17, and the pushing pin 17 can be operated to push the adjusting pin 11 to overcome the disconnection preload so that the first connecting seat 7 and the second connecting seat 8 are connected synchronously; the disconnection preload is applied by a spring 18 arranged in the pin hole of the first connecting seat 8; when the engine is running at high speed, the adjusting pin 11 can be operated and extended into the pin hole 12 of the first connecting seat 7 and the second connecting seat 8 at the same time to complete the connection synchronization of the high-speed intake arm 6 and the low-speed intake rocker arm 5. When the engine switches from high speed back to low speed, the adjusting pin 11 is no longer operated and is reset under the action of the disconnection preload.

[0033] In this embodiment, the adjusting pin 11 is arranged in the pin hole 12 of the first connecting seat 7, and a spring 18 for applying a disconnection preload force is provided in the pin hole 12 of the first connecting seat 7, one end of the spring 18 presses on the adjusting pin 11, and the other end presses on the inner wall of the pin hole 12; the size of the pin hole 12 is determined according to the adjusting pin 11, and the extending section of the adjusting pin 11 extending into the pin hole 12 is preferably cylindrical, which can reduce the jamming of the low-speed intake rocker arm 5 and the high-speed intake arm 6 during connection and disconnection, and can also reduce the wear between the adjusting pin 11 and the pin hole 12, thereby extending the service life; the spring 18 is sleeved on a cylindrical section of the adjusting pin 11, and a compression end face 19 is provided on the adjusting pin 11, and one end of the spring 18 presses on the compression end face 19 on the adjusting pin 11.

[0034] In this embodiment, an end 20 is provided at the end of the push pin 17, and the end 20 of the push pin can cover the moving trajectory of the adjusting pin shaft 11 as the low-speed intake rocker arm 5 and the high-speed intake arm 6 swing. The adjusting pin shaft 11 deviates from the axis of the push pin end 20 and is connected to the push pin end 20; in the limited assembly space of the engine, the push pin 17 and the adjusting pin shaft 11 are used instead of a single pin shaft. The overall weight of the push pin 17 and the adjusting pin 11 shaft is lower than that of a single pin shaft, which can achieve the effect of lightweight design and reduce the overall weight of the engine. The adjusting pin shaft 11 deviates from the axis of the push pin end 20 and is connected to the push pin end 20, which can avoid the adjusting pin shaft 11 and the push pin 17 from interfering with other parts during use.

[0035] In this embodiment, Figure 7 As shown, the camshaft 1 is also provided with an exhaust cam 21, and a decompression member 25 and a centrifugal member 26 for driving the decompression member 25 are provided next to the exhaust cam 21. When the engine is started, the decompression member acts on the exhaust rocker arm 22 matched with the exhaust cam 21 to open the exhaust valve 23. After the engine is started, under the action of the centrifugal member 26, the decompression member 25 is separated from the exhaust rocker arm 22; the decompression mechanism composed of the decompression member 25 and the centrifugal member 26 can make the engine easier to start, and can also prevent the crankshaft from reversing and causing impact on the check valve during engine shutdown.

[0036] In this embodiment, the connection and disconnection of the low-speed intake rocker arm 5 and the high-speed intake arm 6 are controlled by the lift adjustment component, so that variable valve timing and valve lift can be achieved. However, due to the increase in the number of cams on the camshaft 1, the space on the camshaft 1 is very limited. Figure 7As shown, a decompression mechanism composed of a decompression member 25 and a centrifugal member 26 is arranged between the exhaust cam 21 and the timing driven wheel 24. A decompression mechanism can also be arranged between the variable intake cam (referring to the low-speed intake cam 3 and the high-speed intake cam 4) and the exhaust cam 21. However, under the premise of realizing variable valve timing phase and valve lift, the space for the decompression mechanism on the camshaft 1 is limited. The space between the variable intake cam and the exhaust cam 21 is generally a fixed design size, and the space is very limited. Compared with the decompression mechanism between the intake cam and the exhaust cam 21, the decompression mechanism between the exhaust cam 21 and the timing driven wheel 24 is more reasonably used in space. Both arrangements can ensure that the decompression mechanism can be located between the timing driven wheel 24 and the intake cam 21, which can reduce the overall weight of the camshaft and narrow the chain cavity width on the timing driven wheel 24, thereby controlling the overall external dimensions of the engine. After the bearing is pressed, the decompression mechanism and the camshaft 1 are integrated to facilitate assembly.

[0037] The utility model also provides an engine, on which the variable valve timing and valve lift device described above is installed; when the engine speed is at a low speed, the solenoid valve 13 and the lift adjustment component stop working, the high-speed intake arm 6 and the low-speed intake rocker arm 5 are disconnected, the high-speed intake arm 6 idles under the drive of the high-speed intake cam 4, and always keeps in contact with the high-speed intake cam 4 under the action of the torsion spring 14, and the low-speed intake rocker arm 5 is in a working state under the drive of the low-speed intake cam 3 to control the opening and closing of the intake valve 9; when the engine speed increases and reaches a high speed, the solenoid valve 13 pushes the push pin 17 to drive the adjustment pin shaft 11, so that the adjustment pin shaft 11 extends into the pin hole 12 of the second connecting seat 8, and the high-speed intake arm 6 and the low-speed intake rocker arm 5 are in a working state under the drive of the low-speed intake cam 3. The high-speed intake rocker arm 5 is connected synchronously. Since the lift of the high-speed intake cam 4 is greater than that of the low-speed intake cam 3, the high-speed intake cam 4 replaces the low-speed intake cam 3 at this time, and the high-speed intake arm 6 drives the low-speed intake rocker arm 5 to rotate around the rocker arm shaft 2 to control the opening and closing of the intake valve 9; when the engine speed decreases from high speed to low speed, the disconnection preload force applied by the spring 18 in the pin hole 12 of the first connecting seat 7 to the adjusting pin shaft 11 will drive the adjusting pin shaft 11 to retract from the pin hole 12 of the second connecting seat 8 to the pin hole 12 of the first connecting seat 7, the high-speed intake arm 6 and the low-speed intake rocker arm 5 are disconnected, the high-speed intake arm 6 no longer drives the low-speed intake rocker arm 5 to rotate around the rocker arm shaft 2, and the low-speed intake cam 3 drives the low-speed intake rocker arm 5 to control the opening and closing of the intake valve 9.

[0038] 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 it. Although the utility model has been described in detail with reference to the preferred embodiments, ordinary technicians in the field should understand that the technical solution of the utility model can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution of the utility model, which should be included in the scope of the claims of the utility model.

Claims

1. A variable valve timing and valve lift device, characterized in that: It includes a camshaft, a rocker shaft and a lift adjustment component, the camshaft is provided with a low-speed intake cam and a high-speed intake cam, the rocker shaft is provided with a low-speed intake rocker arm and a high-speed intake arm which respectively cooperate with the low-speed intake cam and the high-speed intake cam; the lift adjustment component includes a first connecting seat fixed to the low-speed intake rocker arm and a second connecting seat fixed to the high-speed intake arm, the first connecting seat and the second connecting seat are arranged directly above the rocker shaft or on the upper side close to the camshaft, and the first connecting seat and the second connecting seat can be operated to be connected synchronously or disconnected.

2. The variable valve timing and valve lift device according to claim 1, characterized in that: The lift adjustment assembly also includes an adjustment pin shaft, and the first connecting seat and the second connecting seat are respectively provided with pin holes. The adjustment pin shaft can be operated to simultaneously penetrate the pin holes of the first connecting seat and the second connecting seat to form the connection synchronization, or can be operated to pull out at least one pin hole to form the disconnection.

3. The variable valve timing and valve lift device according to claim 1, characterized in that: The high-speed intake arm is applied with a limiting preload force that always keeps in contact with the high-speed intake cam.

4. The variable valve timing and valve lift device according to claim 3, characterized in that: The limiting preload force is applied by a torsion spring arranged on the rocker arm shaft.

5. The variable valve timing and valve lift device according to claim 2, characterized in that: The adjusting pin is provided with a disconnecting preload, and the preload has a tendency to drive the adjusting pin to disconnect the first connecting seat and the second connecting seat. The lift adjusting assembly also includes a pushing pin, and the pushing pin can be operated to push the adjusting pin to overcome the disconnecting preload so that the first connecting seat and the second connecting seat are connected synchronously.

6. The variable valve timing and valve lift device according to claim 5, characterized in that: The disconnection preload force is applied by a spring arranged in the pin hole of the first connection seat.

7. The variable valve timing and valve lift device according to claim 6, characterized in that: The adjusting pin is arranged in the pin hole of the first connecting seat. A spring for applying a disconnection preload force is arranged in the pin hole of the first connecting seat. One end of the spring presses against the adjusting pin, and the other end presses against the inner wall of the pin hole.

8. The variable valve timing and valve lift device according to claim 5, characterized in that: The end of the push pin is provided with an end head, and the end head of the push pin can cover the moving trajectory of the adjustment pin shaft as the low-speed intake rocker arm and the high-speed intake arm swing. The adjustment pin shaft deviates from the axis center of the push pin end head and is connected to the push pin end head.

9. The variable valve timing and valve lift device according to claim 1, characterized in that: An exhaust cam is also provided on the camshaft, and a decompression member and a centrifugal member for driving the decompression member are provided next to the exhaust cam. When the engine is started, the decompression member acts on the exhaust rocker arm to open the exhaust valve. After the engine is started, the decompression member is separated from the exhaust rocker arm under the action of the centrifugal member.

10. An engine, characterized in that: The engine is equipped with a variable valve timing and valve lift device as described in any one of claims 1 to 8.