Variable valve lift apparatus and vehicle

Abstract

The invention belongs to the technical field of vehicles, and discloses a variable valve lift device and a vehicle, the variable valve lift device comprises a rocker arm shaft, an electromagnetic valve, a cam, a fixed rocker arm and a switching rocker arm, the electromagnetic valve is arranged on a support of the rocker arm shaft, the electromagnetic valve is provided with an oil supply way communicated with an engine main oil way, the responsiveness and reliability of a system are improved, and the reliability of the system is improved. The cam is arranged on the rocker arm shaft, the fixed rocker arm is arranged on the rocker arm shaft and can make contact with the cam, the fixed rocker arm is provided with a driving part, the shell is provided with a switching oil way, the switching oil way is communicated with the oil supply way, and the valve is arranged in the shell and divides the shell into a force transmission cavity and a pressure relief cavity. The plunger is arranged in the force transmission cavity in a sliding mode and can make contact with the driving part, the two ends of the first elastic piece are connected to the plunger and the valve respectively, the push rod is arranged in the pressure relief cavity in a sliding mode and can open or close the valve, the two ends of the second elastic piece are connected to the push rod and the bottom wall of the pressure relief cavity respectively, lock pin mechanical force transmission is replaced with hydraulic force transmission, and switching noise is eliminated.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicles, and in particular to a variable valve lift device and a vehicle. Background Art

[0002] In heavy-duty commercial engines, variable valve technology is being introduced to reduce fuel consumption. This technology utilizes a switching control device within the rocker arm to adjust valve lift based on performance requirements. Two-stage valve lift switching is the most commonly used design.

[0003] Existing variable valve lift rocker arm assemblies switch between two valve lift settings by changing the position of a locking pin between rollers, resulting in compact components. However, load transmission via a mechanical locking pin inevitably produces unusual noise during the switching process, and switching failures can occur, leading to reliability issues with the valvetrain system.

[0004] Therefore, there is an urgent need for a variable valve lift device and a vehicle to solve the above problems. Summary of the Invention

[0005] The object of the present invention is to provide a variable valve lift device that uses hydraulic force transmission instead of lock pin mechanical force transmission, eliminates switching noise, and can improve system responsiveness and reliability.

[0006] In order to solve the above problems existing in the prior art, the present invention adopts the following technical solutions:

[0007] Variable valve lift device, including:

[0008] rocker arm shaft;

[0009] A solenoid valve, the solenoid valve being arranged on a support of the rocker arm shaft and having an oil supply passage connected to a main oil passage of the engine;

[0010] a cam, the cam being arranged on the rocker arm shaft;

[0011] a fixed rocker arm, the fixed rocker arm being arranged on the rocker arm shaft and capable of contacting the cam, the fixed rocker arm being provided with a driving portion;

[0012] A switching rocker arm, the switching rocker arm includes a housing, a valve, a first elastic member, a second elastic member, a plunger and a push rod, the housing is arranged on the rocker arm shaft, the housing is provided with a switching oil circuit, the switching oil circuit is connected to the oil supply circuit, the valve is arranged in the housing and divides the housing into a force transmission chamber and a pressure relief chamber, the plunger is slidably arranged in the force transmission chamber and can contact the driving part, the two ends of the first elastic member are respectively connected to the plunger and the valve, the push rod is slidably arranged in the pressure relief chamber and can open or close the valve, and the two ends of the second elastic member are respectively connected to the push rod and the bottom wall of the pressure relief chamber.

[0013] Preferably, the plunger is provided with a first groove, one end of the first elastic member is arranged in the first groove, the valve is provided with a first protrusion, and the other end of the first elastic member is sleeved on the first protrusion.

[0014] Preferably, the push rod is provided with a second groove, one end of the second elastic member is arranged in the second groove, the bottom wall of the pressure relief chamber is provided with a second protrusion, and the other end of the second elastic member is sleeved on the second protrusion.

[0015] Preferably, the first elastic member and the second elastic member are both configured as return springs.

[0016] Preferably, the rocker arm shaft is provided with a first oil circuit, the support is provided with a second oil circuit, one end of the first oil circuit is connected to the switching oil circuit, the other end of the first oil circuit is connected to one end of the second oil circuit, and the other end of the second oil circuit is connected to the oil supply circuit.

[0017] Preferably, the cam is configured as a dual-lift cam, and the dual-lift cam is in contact with the fixed rocker arm and the switching rocker arm.

[0018] Preferably, when the push rod is separated from the valve, the valve is in a closed state so that the force transmission chamber forms a high-pressure oil chamber, and when the push rod is in contact with the valve, the valve is in an open state so that the oil in the force transmission chamber enters the pressure relief chamber.

[0019] Preferably, the housing includes a shell and a plug, the shell is arranged on the rocker arm shaft, a through hole is opened at the bottom of the shell, and the plug is detachably connected to the through hole.

[0020] Preferably, the switching oil circuit is located in the pressure relief chamber.

[0021] To achieve the above-mentioned object, the present invention further provides a vehicle, comprising an engine and the above-mentioned variable valve lift device, wherein the variable valve lift device is arranged in the engine.

[0022] The beneficial effects of the present invention are:

[0023] The variable valve lift device provided by the present invention comprises a solenoid valve mounted on a support of a rocker shaft. The solenoid valve includes an oil supply circuit connected to the engine's main oil circuit, thereby improving system responsiveness and reliability. A cam is mounted on the rocker shaft, and a fixed rocker arm is mounted on the rocker shaft and capable of contacting the cam. The fixed rocker arm includes a drive unit for interactively transmitting force with the switching rocker arm to achieve force transmission with the switching rocker arm. A housing is mounted on the rocker shaft and includes a switching oil circuit connected to the oil supply circuit. A valve is disposed within the housing, dividing the housing into a force transmission chamber and a pressure relief chamber. A plunger is slidably mounted in the force transmission chamber and capable of contacting the drive unit. Two ends of a first elastic member are respectively connected to the plunger and the valve. A push rod is slidably mounted in the pressure relief chamber and capable of opening or closing the valve. Two ends of a second elastic member are respectively connected to the push rod and the bottom wall of the pressure relief chamber. When the solenoid valve is energized, engine oil enters the switching oil circuit through the oil supply circuit, increasing the oil pressure in the pressure relief chamber and causing the push rod to slide relative to the housing and separate from the valve. At the same time, the oil enters the force transmission chamber through the valve to generate driving force. When the valve closes, the force transmission chamber forms a sealed high-pressure oil chamber, pushing the fixed rocker arm's drive unit to achieve the second valve lift. Under the action of the first elastic member, the plunger and the drive unit are in close contact, preventing impact and abnormal noise. When the solenoid valve is de-energized, the oil in the switching oil circuit loses pressure. The push rod, under the action of the second elastic member, contacts the valve, opening the valve and releasing the oil in the force transmission chamber. The pressure inside the force transmission chamber drops rapidly, eliminating the driving force on the fixed rocker arm and restoring the valve lift to its previous state. The hydraulic force transmission replaces the mechanical force transmission of the locking pin, eliminating the switching noise.

[0024] The vehicle provided by the present invention includes an engine and a variable valve lift device, which is mounted on the engine. A solenoid valve is mounted on a rocker arm shaft support. Switching between two lift modes is achieved by turning the solenoid valve on and off. The rocker arm shaft support is connected to the engine's main oil circuit and directly supplies oil to the solenoid valve's oil supply circuit, thereby improving the engine's responsiveness and reliability. The variable valve lift device uses hydraulic force transmission instead of mechanical force transmission via a lock pin, eliminating switching noise. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 A schematic structural diagram of a variable valve lift device provided in an embodiment of the present invention;

[0026] Figure 2 A schematic structural diagram of a fixed rocker arm provided in an embodiment of the present invention;

[0027] Figure 3 A partial cross-sectional view of a switching rocker arm provided in an embodiment of the present invention;

[0028] Figure 4Schematic diagram of the oil circuit of the solenoid valve and rocker shaft support provided in an embodiment of the present invention.

[0029] Reference numerals:

[0030] 1. Rocker arm shaft; 2. Solenoid valve; 3. Support; 4. Oil supply circuit; 5. Cam; 6. Fixed rocker arm; 7. Drive unit; 8. Switching rocker arm; 9. Housing; 10. Valve; 11. First elastic member; 12. Second elastic member; 13. Plunger; 14. Push rod; 15. Switching oil circuit; 16. First protrusion; 17. Second protrusion; 18. First oil circuit; 19. Second oil circuit; 20. Plug. DETAILED DESCRIPTION

[0031] The present invention will be further described in detail below with reference to the accompanying drawings and examples. It will be understood that the specific embodiments described herein are intended only to illustrate the present invention and are not intended to limit the present invention. It should also be noted that, for ease of description, the accompanying drawings only illustrate portions relevant to the present invention, not all structures.

[0032] In the description of the present invention, unless otherwise expressly specified or limited, the terms "connected," "connected," and "fixed" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention in specific circumstances.

[0033] In the present invention, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Furthermore, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0034] In the description of this embodiment, terms such as "upper," "lower," "left," and "right" are used to refer to positions or locations based on those shown in the accompanying drawings. These terms are intended solely to facilitate description and simplify operation, and are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on the present invention. Furthermore, the terms "first" and "second" are used solely for descriptive purposes and have no special meaning.

[0035] like Figure 1-Figure 4 As shown, in this embodiment, the variable valve lift device includes a rocker shaft 1, a solenoid valve 2, a cam 5, a fixed rocker arm 6, and a switching rocker arm 8. The solenoid valve 2 is mounted on a support 3 of the rocker shaft 1 and defines an oil supply line 4 connected to the engine's main oil circuit. The cam 5 is mounted on the rocker shaft 1, and the fixed rocker arm 6 is mounted on the rocker shaft 1 and capable of contacting the cam 5. The fixed rocker arm 6 is provided with a drive unit 7. The switching rocker arm 8 includes a housing 9, a valve 10, a first elastic member 11, a second elastic member 12, a plunger 13, and a push rod 14. The first elastic member 11 and the second elastic member 12 are both configured as return springs. The housing 9 is arranged on the rocker shaft 1, and the housing 9 is provided with a switching oil circuit 15, which is connected to the oil supply circuit 4. The valve 10 is arranged in the housing 9 and divides the housing 9 into a force transmission chamber and a pressure relief chamber. The plunger 13 is slidably arranged in the force transmission chamber and can contact the driving part 7. The two ends of the first elastic member 11 are respectively connected to the plunger 13 and the valve 10. The push rod 14 is slidably arranged in the pressure relief chamber and can open or close the valve 10. The two ends of the second elastic member 12 are respectively connected to the push rod 14 and the bottom wall of the pressure relief chamber.

[0036] The solenoid valve 2 is mounted on the support 3 of the rocker arm shaft 1. This support 3 is connected to the engine's main oil circuit and directly supplies oil to the oil supply line 4 of the solenoid valve 2, thereby improving system responsiveness and reliability. The cam 5 is configured as a dual-lift cam 5, which contacts both the fixed rocker arm 6 and the switching rocker arm 8 to achieve two valve lifts. The fixed rocker arm 6 is equipped with a drive unit 7, which is used to transmit force to and from the switching rocker arm 8. The switching rocker arm 8 is internally designed with a high-pressure oil force transmission module and a pressure release module. The high-pressure oil force transmission module includes a plunger 13, a valve 10, and a first elastic member 11. One end of the plunger 13 slides within the housing, while the other end extends relative to the housing and can contact the drive unit 7. The first elastic member 11 is elastically disposed between the valve 10 and the plunger 13. When valve 10 is closed, the force transmission chamber forms a closed, high-pressure oil chamber. The plunger 13 pushes the drive unit 7 of the fixed rocker arm 6 to transmit force. Under the action of the first elastic element, the plunger 13 and the drive unit 7 are in close contact, preventing any impact or noise. The cam 5 contacts the fixed rocker arm 6, achieving the two-lift switching function. The pressure release module includes a push rod 14 and a second elastic element 12. A switching oil circuit 15 is located within the pressure relief chamber. The push rod 14 slides within the pressure relief chamber, and the second elastic element 12 is elastically disposed between the push rod 14 and the bottom wall of the pressure relief chamber. When oil is flowing through the switching oil circuit 15, the push rod 14 returns to its original position and separates from the valve 10. The second elastic element 12 is compressed, closing the valve 10 and achieving the two-lift switching function. When oil is not flowing through the switching oil circuit 15, the push rod 14, under the action of the second elastic element 12, contacts the valve 10, opening it and releasing the oil, restoring the valve lift to its previous state. Optionally, the switching rocker arm 8 can also be integrated into the fixed rocker arm 6, and the function can be realized by changing the switching position to a roller. In addition, a return spring can be designed outside the switching rocker arm 8 so that the two rocker arms remain in the required position by default.

[0037] The operating principle of this variable valve lift device is as follows: when the solenoid valve 2 is de-energized, oil does not enter the switching oil circuit 15. The cam 5 drives the fixed rocker arm 6 to rotate, while the switching rocker arm 8 is in an idle stroke state and does not exert any influence on the fixed rocker arm 6. When the solenoid valve 2 is energized, oil from the engine's main oil circuit enters the switching oil circuit 15 through the oil supply oil circuit 4 of the solenoid valve 2. The oil pressure in the pressure relief chamber increases, pushing the push rod 14 to slide relative to the housing and separate from the valve 10. Simultaneously, the oil enters the force transmission chamber through the valve 10, generating a driving force. When the valve 10 closes, the force transmission chamber becomes a closed high-pressure oil chamber, which pushes the drive unit 7 of the fixed rocker arm 6 to achieve the second valve lift. When solenoid valve 2 is de-energized again, the oil in switching oil circuit 15 loses pressure. Push rod 14, under the action of second elastic member 12, contacts valve 10, opening valve 10 and releasing the oil in the force transmission chamber. This rapidly reduces the pressure inside the force transmission chamber, eliminating the driving force on fixed rocker arm 6 and restoring valve lift to its previous state. Hydraulic force transmission replaces mechanical force transmission via a lock pin, eliminating switching noise.

[0038] Reference Figure 1 The cam 5 is set as a double lift cam 5, and the double lift cam 5 is in contact with the fixed rocker arm 6 and the switching rocker arm 8 to achieve two valve lifts.

[0039] Reference Figure 3 The plunger 13 defines a first groove, into which one end of the first elastic member 11 is disposed. The valve 10 is provided with a first protrusion 16, into which the other end of the first elastic member 11 is sheathed. The push rod 14 defines a second groove, into which one end of the second elastic member 12 is disposed. The bottom wall of the pressure relief chamber is provided with a second protrusion 17, into which the other end of the second elastic member 12 is sheathed. When the solenoid valve 2 is energized, oil from the engine's main oil circuit enters the switching oil circuit 15 through the solenoid valve 2's oil supply passage 4. The oil pressure in the pressure relief chamber increases, pushing the push rod 14 to slide relative to the housing and separate from the valve 10. The second elastic member 12 is compressed within the second groove. Simultaneously, the valve 10 is closed, forming a high-pressure oil chamber in the force transmission chamber, pushing the drive unit 7 of the fixed rocker arm 6 to achieve the second valve lift. The first elastic member 11 props the first groove against the first protrusion 16, and the plunger 13 fits tightly against the drive unit 7, preventing abnormal impact noise. When the solenoid valve 2 is powered off, the oil in the switching oil circuit 15 loses pressure, the second elastic member 12 extends, the push rod 14 contacts the valve 10, and the valve 10 opens, thereby releasing the oil in the force transmission chamber, causing the pressure inside the force transmission chamber to drop rapidly, and no driving force is generated on the fixed rocker arm 6, and the valve lift returns to its previous state.

[0040] Reference Figure 4The rocker arm shaft 1 defines a first oil passage 18, and the support 3 defines a second oil passage 19. One end of the first oil passage 18 communicates with the switching oil passage 15, and the other end of the first oil passage 18 communicates with one end of the second oil passage 19. The other end of the second oil passage 19 communicates with the oil supply passage 4. When the solenoid valve 2 is in operation, the oil in the oil supply passage 4 is drawn into the second oil passage 19 within the support 3 of the rocker arm shaft 1. The oil is then transferred through the first oil passage 18 within the rocker arm shaft 1 to the oil passage within the switching rocker arm 8, achieving a rapid response.

[0041] Continue to refer to Figure 3 The housing 9 includes a shell and a plug 20. The shell is mounted on the rocker shaft 1. A through hole is formed at the bottom of the shell, and the plug 20 is removably connected to the through hole. The outer periphery of the plug 20 is provided with an external thread, and the inner periphery of the through hole is provided with an internal thread. The plug 20 is threadedly connected to the through hole, which facilitates the quick removal of the plug 20 to clean the oil in the pressure relief chamber and replace the second elastic member 12, the push rod 14, and the valve 10.

[0042] This embodiment also provides a vehicle comprising an engine and a variable valve lift device, the variable valve lift device being mounted on the engine. A solenoid valve 2 is mounted on a support 3 of a rocker arm shaft 1. Switching between two lift modes is achieved by turning the solenoid valve 2 on and off. The support 3 of the rocker arm shaft 1 is connected to the engine's main oil circuit and directly supplies oil to the oil supply circuit 4 of the solenoid valve 2, thereby improving the engine's responsiveness and reliability. The variable valve lift device uses hydraulic force transmission instead of mechanical force transmission via a locking pin, eliminating switching noise.

[0043] Obviously, the above embodiments of the present invention are merely examples for the purpose of clearly illustrating the present invention and are not intended to limit the embodiments of the present invention. A person skilled in the art would be able to make various obvious changes, readjustments, and substitutions without departing from the scope of protection of the present invention. It is not necessary and impossible to enumerate all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the claims of the present invention.

Claims

1. A variable valve lift device, characterized in that: include: Rocker arm shaft (1); A solenoid valve (2), the solenoid valve (2) being arranged on a support (3) of the rocker arm shaft (1), and the solenoid valve (2) being provided with an oil supply passage (4) connected to a main oil passage of the engine; A cam (5), wherein the cam (5) is arranged on the rocker arm shaft (1); a fixed rocker arm (6), the fixed rocker arm (6) being arranged on the rocker arm shaft (1) and capable of contacting the cam (5), the fixed rocker arm (6) being provided with a driving portion (7); A switching rocker arm (8), the switching rocker arm (8) comprising a housing (9), a valve (10), a first elastic member (11), a second elastic member (12), a plunger (13) and a push rod (14), the housing (9) being arranged on the rocker arm shaft (1), the housing (9) being provided with a switching oil circuit (15), the switching oil circuit (15) being connected to the oil supply circuit (4), the valve (10) being arranged in the housing (9) and dividing the housing (9) into a force transmission chamber and a pressure relief chamber, the plunger (13) being slidably arranged in the force transmission chamber and being capable of contacting the driving part (7), the two ends of the first elastic member (11) being respectively connected to the plunger (13) and the valve (10), the push rod (14) being slidably arranged in the pressure relief chamber and being capable of opening or closing the valve (10), and the two ends of the second elastic member (12) being respectively connected to the push rod (14) and the bottom wall of the pressure relief chamber.

2. The variable valve lift device according to claim 1, characterized in that: The plunger (13) is provided with a first groove, one end of the first elastic member (11) is arranged in the first groove, the valve (10) is provided with a first protrusion (16), and the other end of the first elastic member (11) is sleeved on the first protrusion (16).

3. The variable valve lift device according to claim 1, characterized in that: The push rod (14) is provided with a second groove, one end of the second elastic member (12) is arranged in the second groove, the bottom wall of the pressure relief chamber is provided with a second protrusion (17), and the other end of the second elastic member (12) is sleeved on the second protrusion (17).

4. The variable valve lift device according to claim 1, characterized in that: The first elastic member (11) and the second elastic member (12) are both configured as return springs.

5. The variable valve lift device according to claim 1, characterized in that: The rocker arm shaft (1) is provided with a first oil circuit (18), and the support (3) is provided with a second oil circuit (19). One end of the first oil circuit (18) is connected to the switching oil circuit (15), the other end of the first oil circuit (18) is connected to one end of the second oil circuit (19), and the other end of the second oil circuit (19) is connected to the oil supply circuit (4).

6. The variable valve lift device according to claim 1, characterized in that: The cam (5) is configured as a double-lift cam (5), and the double-lift cam (5) is in contact with the fixed rocker arm (6) and the switching rocker arm (8).

7. The variable valve lift device according to claim 1, characterized in that: When the push rod (14) is separated from the valve (10), the valve (10) is in a closed state so that the force transmission chamber forms a high-pressure oil chamber; when the push rod (14) is in contact with the valve (10), the valve (10) is in an open state so that the oil in the force transmission chamber enters the pressure relief chamber.

8. The variable valve lift device according to claim 1, characterized in that: The housing (9) comprises a shell and a plug (20); the shell is arranged on the rocker shaft (1); a through hole is provided at the bottom of the shell; and the plug (20) is detachably connected to the through hole.

9. The variable valve lift device according to claim 1, characterized in that: The switching oil circuit (15) is located in the pressure relief chamber.

10. A vehicle, characterized in that It comprises an engine and the variable valve lift device according to any one of claims 1 to 9, wherein the variable valve lift device is arranged in the engine.

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