CN210087426U

CN210087426U - Valve lift device with valve lift and valve opening time simultaneously variable

Info

Publication number: CN210087426U
Application number: CN201920996293.1U
Authority: CN
Inventors: 曾明杰; 罗小龙
Original assignee: GAC Mitsubishi Motors Co Ltd
Current assignee: GAC Mitsubishi Motors Co Ltd
Priority date: 2019-06-28
Filing date: 2019-06-28
Publication date: 2020-02-18
Anticipated expiration: 2029-06-28

Abstract

The utility model discloses a valve lift and valve opening time changeable valve lift device simultaneously, including drive cam, swing arm and valve subassembly, swing arm one end is articulated, and valve assembly is used to one end in addition, drive cam rotates the assembly and acts on the both ends intermediate position of swing arm at a fixed position, exerts pressure to the swing arm, and leverage control valve through the swing arm opens, the swing arm articulates on the slider, the slider direction sets up to be connected with a pushing mechanism, pushing mechanism drive slider and swing arm are together slided to make the articulated fulcrum of swing arm, swing arm and drive cam's action position and swing arm and valve assembly's action position take place continuous variation. The utility model discloses an adjustment swing arm and drive cam's relative position realizes that both are continuously variable in valve lift and valve opening time angle, has improved the intake and exhaust efficiency of engine, has promoted economics, dynamic property and the emission performance of engine.

Description

Valve lift device with valve lift and valve opening time simultaneously variable

Technical Field

The utility model relates to an engine valve actuating mechanism, concretely relates to valve lift and valve opening time changeable valve lift device simultaneously.

Background

For most engines, the lift of the intake valve and the exhaust valve is fixed and invariable, namely, the cam profile of the camshaft is only one. This makes it impossible for the lift to give a good response of the engine in both the high speed region and the low speed region. The valve lift-cam profile design of the traditional engine is a balanced selection of the engine under all working conditions, and as a result, the engine cannot obtain the optimal high-speed efficiency and the optimal low-speed torque, so that the air intake loss occurs and the fuel consumption is excessive.

The adoption of the Variable Valve Lift (VVL) ensures that the engine can obtain the valve lift meeting the requirements in a high-speed area and a low-speed area, thereby improving the high-speed power and the low-speed torque of the engine. The existing realization of the variable valve lift comprises two structural forms, one is to adopt a plurality of cams to control an air inlet rocker arm and switch to cams with different heights to realize different opening control of the valve, the valve lift change can only be controlled by the number of the cams, generally two groups of cams or three groups of cams, and the continuous stepless change of the valve lift cannot be realized; the other mode is that the hydraulic unit directly drives the valve to open and close, and the mode can realize stepless continuous change of the valve lift, but the arrangement of the hydraulic unit makes the structure of the engine mechanism more complex, needs to carry out larger structural modification on the existing engine valve structure, and has reliable mechanical structure without cam and rocker arm control in work.

SUMMERY OF THE UTILITY MODEL

The utility model provides a technical problem be: aiming at the existing variable valve lift technology, a valve lift device with the valve lift and the valve opening time variable simultaneously is provided.

The utility model discloses a following technical scheme realizes:

a valve lift device with simultaneously variable valve lift and valve opening time comprises a driving cam 10, a swing arm 20 and a valve assembly 30, wherein one end of the swing arm 30 is hinged, the other end of the swing arm is acted on the valve assembly 30, the driving cam 10 is rotatably assembled at a fixed position and acts on the middle positions of two ends of the swing arm 20, pressure is applied to the swing arm 20, the valve is controlled to be opened through the lever action of the swing arm 20, the swing arm 20 is hinged on a sliding block 40, the sliding block 40 is arranged in a guiding mode and is connected with a pushing mechanism 50, and the pushing mechanism 50 drives the sliding block 40 and the swing arm 20 to slide together, so that the hinged fulcrum of the swing arm 20, the action positions of the swing arm 20 and the driving cam 10 and the action positions of the swing arm.

Further, the sliding block 40 is guided and assembled in the fixed sliding groove 80.

Further, the end of the swing arm 20 is hinged to the slider 40 through a rotating shaft 60, and a first spring 70 is disposed at the hinged position of the slider 40 and the swing arm 20 to make the swing arm 20 always act on the valve assembly 30.

Further, the swing arms 20 corresponding to the synchronously acting valve assemblies 30 are assembled on the same slide block 40 through the same rotating shaft 60.

In the continuously variable valve lift apparatus of the present invention, it is preferable that the pushing mechanism 50 is a cam mechanism including a control cam 51 for driving the slider 40 to move in the slide groove 80 and a second spring 53 for making the slider 40 contact the control cam 51 all the time.

Furthermore, one end of the second spring 53 is connected to the slider 40, and the other end is connected to the sliding slot 80 through the fixed shaft 52, the control cam 51 pushes the slider 40 to elastically deform the second spring 53, and the elastic force generated by the second spring 53 controls the slider 40 to be in pressing contact with the control cam 51.

The present invention is preferably applied to a continuously variable valve lift apparatus, wherein the pushing mechanism 50 is a screw mechanism, a rack-and-pinion mechanism, a slider-crank mechanism, an electric push rod, or a hydraulic push rod.

Further, the action side surfaces of the swing arm 20 and the drive cam 10 are arranged obliquely with respect to the sliding direction of the swing arm 20.

The utility model realizes the high sensitivity and large-scale adjustment of the valve lift by changing the position change of the lever structure formed among the driving cam, the swing arm and the valve component, and the driving cam acts on the swing arm to lead the swing arm to do rotary swing with a hinged fulcrum, and the tail end of the swing arm is contacted with the valve tappet and is pressed down, thereby driving the valve to open; the swing arm is hinged with the sliding block through the rotating shaft, the sliding block is pushed through the pushing mechanism, so that the sliding block moves back and forth in the sliding groove, the swing arm is caused to move integrally, the action positions of the hinged fulcrum of the swing arm, the swing arm and the driving cam and the action positions of the swing arm and the valve assembly are changed, and the valve lift is continuously variable.

The utility model discloses in still set up swing arm and drive cam's effect side for the direction slip direction of swing arm and slider itself to the inclined plane, make drive cam's advance angle of repose working face also can change along with the direction slip of swing arm and slider for the clearance between the swing arm like this, the change in this clearance leads to the effect angle of drive cam promotion swing arm to change, valve opening time angle synchronous continuous variation when finally realizing the valve lift change. Even the relative position of the swing arm and the driving cam is adjusted until the clearance between the swing arm and the driving cam exceeds the lift of the driving cam, the cylinder closing control of the engine corresponding to the valve can be realized.

To sum up, the utility model discloses a continuous variable valve lift device is adjustment swing arm on rocking arm formula valve mechanical structure's basis is sliding structure, the valve lift and the valve opening time angle of adaptation engine different operating modes are continuously variable simultaneously, make the engine provide best valve lift and valve opening time angle in full rotational speed scope, whole still with rocking arm air door's mechanical structure, need not change the valve structure of current engine by a wide margin, moreover, the mechanical structure cost is lower, the operation is reliable, the same pivot assembly of synchronous motion's valve accessible is on same slider, greatly improve assembly efficiency and maintenance convenience, can realize the valve independent control of each jar between the valve of different actions, the efficiency of advancing and exhausting of engine is improved, the economics of engine has been promoted, dynamic property and emission performance.

The present invention will be further described with reference to the accompanying drawings and the following detailed description.

Drawings

Fig. 1 is a schematic diagram of a valve lift apparatus in an embodiment.

Fig. 2 is a schematic diagram showing a valve lift increasing state of the valve lift apparatus in the embodiment.

Fig. 3 is a lever diagram of the valve lift apparatus in the embodiment.

Fig. 4 is a schematic view of a slider structure in the embodiment.

Fig. 5 is an assembly diagram of the swing arm and the slider in the embodiment.

Fig. 6 is an assembly diagram of the entire valve lift apparatus in the embodiment.

Reference numbers in the figures: 10-driving cam, 20-swing arm, 30-valve assembly, 31-valve tappet, 32-valve, 40-sliding block, 50-pushing mechanism, 51-control cam, 52-fixed shaft, 53-second spring, 60-rotating shaft, 70-first spring and 80-sliding chute.

Detailed Description

Examples

Referring to fig. 1 and 2, the valve lift apparatus in which the valve lift and the valve open time are simultaneously variable is an embodiment of the present invention, and specifically includes a driving cam 10, a swing arm 20, a valve assembly 30, a slider 40, a pushing mechanism 50, a rotating shaft 60, a first spring 70, and a sliding groove 80. The valve assembly 30 includes a valve lifter 31 and a valve 32, which are respectively installed at an intake port and an exhaust port of each cylinder of the engine, and are normally closed, and open the valves by pressing down the valve assembly 30. The valve assembly 30 in this embodiment adopts a rocker arm type valve mechanical structure to control opening, wherein one end of the swing arm 20 is hinged to serve as a lever fulcrum, the swing arm 20 has a rotational degree of freedom swinging by taking the hinge point as a center, the other end of the swing arm 20 directly acts on the top of the valve tappet 31 of the valve assembly 30, the driving cam 10 acts on the upper portion of the middle position of the two ends of the swing arm 20, the driving cam 10 pushes the swing arm 20 to swing downwards intermittently, the valve tappet 31 is pressed downwards through the lever action of the swing arm 20, and then the valve 32 below is pushed to move downwards, so that opening of the valve is realized, the swing angle of the swing arm 20 controls the opening lift of the valve 32, namely the opening degree of air intake of the.

The rocker arm type valve mechanical structure is a conventional valve control structure, and in the embodiment, the rocker arm 20 is movably arranged, and the lever action of the rocker arm and the driving cam on the valve assembly is changed by moving the position of the rocker arm 20, so that the continuous variable lift control of the valve is realized.

Specifically, the swing arm 20 in this embodiment is hinged to the slider 40, the slider 40 is guided and assembled in the fixed sliding slot 80, so that the swing arm 20 has a linear degree of freedom to slide integrally along the slider 40 while swinging relative to the slider 40, the slider 40 is connected with the pushing mechanism 50, and the driving force for the slider 40 and the swing arm 20 to linearly slide back and forth along the sliding slot 80 is realized through the pushing mechanism 50. The other end of the swing arm 20 is in contact connection with the top surface of the valve tappet 31, the installation position of the driving cam 10 is fixed relative to the swing arm 20, and the swing arm 20 continuously moves, so that the hinge point of the swing arm 20, the action positions of the swing arm 20 and the driving cam 10 and the action positions of the swing arm 20 and the valve assembly 30 are continuously changed, and the valve lift is controlled to be continuously variable.

The end of the swing arm 20 is hinged with the slider 40 through the rotating shaft 60, a first spring 70 which always acts on the swing arm 20 on the valve assembly 30 is arranged at the hinged positions of the slider 40 and the swing arm 20, the first spring 70 can adopt a torsion spring structure which is sleeved on the rotating shaft 60 and respectively connected with the swing arm 20 and the slider 40, the end of the swing arm 20 is always contacted on the valve tappet 31 through the rotating torque of the torsion spring, but the acting force applied by the torsion spring should be smaller than the spring reset acting force for opening the valve, namely, the valve can not be directly opened by the acting force applied to the swing arm 20 by the first spring 70.

The slide block 40 is guided and slidably assembled in a fixedly arranged slide groove 80, the slide groove 80 limits the moving direction of the slide block 40, the pushing mechanism 50 pushes the slide block 40 and the swing arm 20 to move along the slide groove 80 from the other end of the slide groove 80, the pushing mechanism 50 in the embodiment is a cam mechanism and comprises a second spring 53 which drives the slide block 40 to push the control cam 51 and the drive slide block 40 to be always contacted with the control cam 51 in the slide groove 80, wherein the end surface of the slide block 40 is acted with the cam surface of the control cam 51 to push the slide block 40 to move towards the direction close to the drive cam in the slide groove 80 through the cam action, one end of the second spring 53 is hung on a rotating shaft 60 hinged with the slide block 40 and the swing arm 20 and moves together with the slide block 40, the other end is hung on a fixed shaft 52 fixedly connected with the slide groove 80 and is fixed relative to the other end, and the second spring 53, the elastic force generated by the second spring 53 controls the slide block 40 to be in pressing contact with the control cam 51 when the control cam rotates to the near-repose angle, and drives the slide block 40 to move in a return stroke. The power of the drive cam 10 and the control cam 51 can be controlled by separate power units and can be synchronously connected with the output shaft of the engine.

The pushing mechanism 50 drives the slider 40 to linearly reciprocate, and in practical application, the pushing mechanism can also be implemented by a screw rod mechanism, a rack and pinion mechanism, a slider-crank mechanism, an electric push rod or a hydraulic push rod, and other linear reciprocating mechanisms, which are not described in detail herein.

The drive cam 10 provides a downward force of the swing arm 20 against the valve lifter 31. The driving cam 10 is rotatably assembled at a fixed position above the swing arm 20, the cam surface of the driving cam acts on the middle position of two ends of the swing arm 20, the driving cam 10 only has a rotational degree of freedom, the position is fixed relative to the swing arm 20, the swing arm 20 is pushed downwards by the cam surface through the rotation of the driving cam 10, the swing arm 20 is pushed to swing downwards, and finally the valve assembly 30 is pushed downwards to open the valve. The valve assembly 30 is closed after the pressing force of the swing arm 20 and the driving cam 10 is lost, and the valve assembly and the engine cylinder body are provided with a return spring.

The driving cam 10 acts on the middle position of the swing arm 20 to make the swing arm 20 perform a lever motion with the hinge point as a fulcrum, and the other end of the swing arm 20 is connected with the valve tappet 31, so that the valve 72 is driven to open and close. The principle of the embodiment for realizing the continuous variable valve lift is that the sliding block 40 and the swing arm 20 are driven by the pushing mechanism 50 to integrally move back and forth so as to adjust the hinge fulcrum of the swing arm 20, the action positions of the swing arm 20 and the driving cam 10 and the action positions of the swing arm 20 and the valve assembly 30, and through the change of the three positions, the force arm of the whole lever action is changed, so that the continuous change of the valve opening lift is realized.

In order to control the valve lift change and adjust the valve opening time corresponding to the changed valve lift, the driving cam 10 is located above the swing arm 20, in the embodiment, the acting side surfaces of the swing arm 20 and the driving cam 10 are arranged obliquely relative to the sliding direction of the swing arm 20 and the slider 40, so that when the swing arm 20 moves integrally, the clearance between the cam surface of the driving cam 10 and the acting side surface of the swing arm 20 changes, the change of the clearance is directly converted into the change of the acting time of the driving cam 10 on the swing arm 20, and the swing arm 20 controls the valve opening time angle and the valve closing time angle at the same time through the change of the clearance, the clearance between the swing arm 20 and the driving cam 10 during the moving process is continuously changed, so the valve opening time angle α also changes continuously, specifically, for the convenience of the description of the valve opening time control of the embodiment, the "valve opening time angle" referred to herein refers to the sum of the pushing angle, the remote resting angle and the return angle of the driving cam 10 contacting the swing arm 20, as α in fig. 1, and the "valve closing time" referred to the driving cam 10 "is the remaining angle after the driving cam 10 is rotated by subtracting the driving cam angle α, and the driving cam is not pushed by the driving cam 20.

In the embodiment, the change of the relative position between the swing arm 20 and the driving cam 10 is realized while the swing arm 20 is adjusted to move, and the continuous change of the valve lift and the valve opening time angle α is realized, in fig. 1, the valve is in a normal state, at the moment, the engine normally works, the valve opening does not need to be increased to increase the air intake amount, and the valve opening does not need to be reduced to reduce the air intake amount, at the moment, a certain gap delta is kept between the swing arm 20 and the near repose angle of the cam surface of the driving cam 10, the gap delta is smaller than the lift of the driving cam 10, and the swing arm 20 inclines for a certain angle to be in contact with the valve tappet 31, when the driving cam 10 continuously rotates through a push angle, a far repose angle and a return stroke to the swing arm 20, the gap delta between the swing arm 20 and the repose angle of the driving cam 10 is pushed to open the valve assembly, so that the normal air intake and exhaust of the engine cylinder is realized, as shown in fig. 2 and 3, in the process that the pushing mechanism 50 pushes the slider 40 and the swing arm 20 to move towards the driving cam side direction of the driving cam, the driving cam 20, the gap delta between the swing arm 20 and the valve lifter arm 20 are continuously changes according to the high load arm, the change of the continuous change of the valve opening time angle α, so that the valve opening arm α is also the load arm α, the load arm is beneficial to the change of the continuous change.

The valve lift and the valve opening time angle α can be continuously reduced by moving the swing arm 20 in the reverse direction, the valve lift and the valve opening time angle can be set to be zero, namely, the technology of closing the cylinder of the engine corresponding to the valve is adopted, at the moment, no matter which angular position the driving cam 10 rotates to, the cam surface of the driving cam 10 cannot be in contact with the swing arm 20, the valve opening time angle α is 0, the corresponding valve closing time angle is 360 degrees, and in the state, the driving cam cannot enable the valve to be opened, so that the cylinder closing of the engine cylinder is realized.

The present embodiment can be respectively installed on the intake valve and the exhaust valve of the cylinder, for the valve assembly with synchronous action, the valve assembly is assembled on the same slide block 40 through the same rotating shaft 60, the structure of the slide block 40 is as shown in fig. 4, the installation position corresponding to a plurality of swing arms 20 is arranged on one side of the slide block 40, all the swing arms 20 are hinged on the slide block 40 through the same rotating shaft 60, as shown in fig. 5, the first spring 70 is correspondingly assembled between the rotating shaft 60 and each swing arm 20, two sets of second springs 53 are hung at the two ends of the rotating shaft 60 and connected with the fixed chute, the slide block 40 and the other side of the slide block are contacted with the control cam of the pushing mechanism 50, as shown in fig. 6, the control cam of the pushing mechanism 50 pushes the slide block 40 to drive all the. The rotating shaft 60 is in a single form, and each part is assembled, so that the parts can be conveniently installed in the sliding groove 80 in an assembly form, and the assembling efficiency is extremely high.

In practical application, independent pushing mechanisms such as a hydraulic push rod or an electric push rod can be adopted to independently control the motion of the sliding block corresponding to the valve swing arm of each cylinder

The above are only preferred embodiments of the present invention, and all changes and modifications made according to the scope of the present invention shall fall within the scope of the claims of the present invention.

Claims

1. A valve lift device with simultaneously variable valve lift and valve opening time comprises a driving cam (10), a swing arm (20) and a valve assembly (30), wherein one end of the swing arm (30) is hinged, the other end of the swing arm is used for the valve assembly (30), the driving cam (10) is rotatably assembled at a fixed position and acts on the middle positions of two ends of the swing arm (20), pressure is applied to the swing arm (20), and the valve is controlled to be opened through the lever action of the swing arm (20), and the device is characterized in that:

the swing arm (20) is hinged to the sliding block (40), the sliding block (40) is arranged in a guiding mode and connected with a pushing mechanism (50), and the pushing mechanism (50) drives the sliding block (40) and the swing arm (20) to slide together, so that a hinged fulcrum of the swing arm (20), the action positions of the swing arm (20) and the driving cam (10) and the action positions of the swing arm (20) and the valve assembly (30) are continuously changed.

2. Valve lift device with simultaneous variable valve lift and valve opening time according to claim 1, the slide (40) being guided in a fixed slide groove (80).

3. A valve lift apparatus with simultaneously variable valve lift and valve open time according to claim 2, wherein the end of the swing arm (20) is hinged with the slider (40) through a rotating shaft (60), and the hinged position of the slider (40) and the swing arm (20) is provided with a first spring (70) which always acts the swing arm (20) on the valve assembly (30).

4. A valve lift apparatus with simultaneous variable valve lift and valve open time according to claim 3, wherein the swing arms (20) corresponding to the synchronously acting valve assemblies (30) are mounted on the same slide block (40) through the same rotating shaft (60).

5. A valve lift apparatus with simultaneous variable valve lift and valve open time according to any one of claims 1 to 4, the urging mechanism (50) being a cam mechanism including a control cam (51) for driving the slider (40) to move within the slide groove (80) and a second spring (53) for always bringing the slider (40) into contact with the control cam (51).

6. The valve lift apparatus with the simultaneous variable valve lift and valve open time according to claim 5, wherein one end of the second spring (53) is connected to the slider (40), the other end of the second spring is connected to the sliding groove (80) through the fixed shaft (52), the control cam (51) pushes the slider (40) to elastically deform the second spring (53), and the elastic force generated by the second spring (53) controls the slider (40) to be in pressing contact with the control cam (51).

7. A valve lift apparatus with simultaneous variable valve lift and valve open time according to any one of claims 1 to 4, wherein the pushing mechanism (50) employs a screw mechanism, a rack and pinion mechanism, a slider-crank mechanism, an electric push rod, or a hydraulic push rod.

8. A valve lift apparatus with simultaneous variable valve lift and valve open time according to claim 1, said swing arm (20) and the active side of the drive cam (10) being arranged obliquely with respect to the sliding direction of the swing arm (20).