KR20200040401A - Continuously variable valve lift system - Google Patents

Abstract

The present invention relates to a variable valve lift device that changes the valve lift according to the movement of the operation pin provided inside the intake / exhaust valve. In the present invention, it is formed through the valve head of the intake valve or exhaust valve so that the combustion chamber and the port can communicate. A gas passage formed so as to be; An operation pin provided to be movable in the intake valve or the exhaust valve and opening or blocking the gas passage according to the movement operation; And an actuating force providing means for providing actuating force for moving the actuating pin.

Description

Variable valve lift device {CONTINUOUSLY VARIABLE VALVE LIFT SYSTEM}

The present invention relates to a variable valve lift device that changes the valve lift according to the movement of the operation pin provided inside the intake / exhaust valve.

Continuously variable valve lift (CVVL) is a technology that maximizes the fuel efficiency and performance of the engine by controlling the valve lift opened at a constant height according to the engine rotation speed.

For example, in the high-speed section, the valve lift is increased to increase the intake air amount, and in the low-speed section, the valve lift is reduced to maintain the intake air amount appropriately, thereby improving engine performance and fuel efficiency, and realizing a smooth acceleration feeling.

However, since there is a limit to optimize the operation efficiency only by controlling the increase or decrease of the valve lift, a method for further optimizing the operation efficiency in the entire operation area is required based on an improvement in the degree of freedom of valve control.

The above descriptions as background arts are only for improving understanding of the background of the present invention, and should not be taken as an admission that they correspond to the prior arts already known to those skilled in the art.

KR 10-1865738 B

The present invention is to provide a variable valve lift device that changes the valve lift according to the movement of the operating pin provided inside the intake and exhaust valves, to solve the problems as described above.

The configuration of the present invention for achieving the above object is formed through the valve head of the intake valve or the exhaust valve gas passage formed so that the combustion chamber and the port can communicate; An operation pin provided to be movable in the intake valve or the exhaust valve and opening or blocking the gas passage according to the movement operation; And an actuation force providing means for providing an actuation force for moving the actuation pin.

An operation hole is hollowly formed along the longitudinal direction of the intake valve or exhaust valve so that the lower end of the operation hole connects with the bottom surface of the valve head; The gas passage is formed between the lower end of the operation hole and the upper surface of the valve head; The operation pin is provided in the operation hole to be linearly movable; One end of the working pin is provided to block between the lower end of the working hole and the gas passage, but according to the linear movement of the working pin, one end of the working pin is spaced from the bottom surface of the valve head so that the lower end of the working hole and the gas passage are opened. Can be configured.

A blocking portion having a shape corresponding to the inner diameter of the working hole is formed at one end of the working pin; The outer diameter of the working pin formed on the upper end of the blocking portion may be smaller than the inner diameter of the working hole.

The operating force providing means includes: an oil passage providing oil pressure in a moving direction of the operating pin; An opening / closing valve provided to enable opening / closing operation on the oil passage; It may include; a controller for controlling the opening and closing operation of the on-off valve based on the phase angle of the crank.

The operating force providing means includes: a valve bridge connected to an upper end of the intake valve or exhaust valve; The oil passage is formed inside the valve bridge, an oil inlet is formed at one end, an oil outlet is formed at the other end, and a middle end is connected to the upper end of the operation hole to provide oil pressure to the operation pin provided inside the operation hole. ; A first opening / closing valve installed on the oil inlet side to be opened and closed; A second opening / closing valve installed on the side of the oil outlet and operated to open and close; And a controller for controlling the opening and closing operation of the first and second opening and closing valves based on the phase angle of the crank.

It may further include; a return spring that provides an elastic restoring force to the operating pin moved by the oil pressure.

A fixed support portion is formed in a shape surrounding the operation pin at an inner middle of the operation hole; A moving support portion is formed on the upper outer surface of the working pin; A return spring may be provided between the movable support part and the fixed support part.

The controller controls to open the first opening / closing valve and closing the second opening / closing valve to supply oil into the operation hole when the operation pin needs to be moved to open the gas passage; When the operation pin needs to be moved to close the gas passage, the first opening / closing valve may be closed, and the second opening / closing valve may be opened to control the oil inside the oil passage to be discharged to the oil outlet.

The present invention through the above-described problem solving means, the exhaust valve in accordance with the movement of the operating pin is formed in a state in which the combustion chamber communicates with the exhaust port in the closed state, thereby exhausting the exhaust gas in the exhaust port through the communicating gas passage to the combustion chamber. It is possible to perform intake and exhaust operations, such as inflow or discharge of compressed gas to the exhaust port in the combustion chamber, thereby optimizing driving efficiency in the entire driving area of the vehicle.

1 is a view showing the configuration of a variable valve lift device according to the present invention.
Figure 2 is a view showing a state in which the operating pin is moved by the oil pressure in Figure 1;
Figure 3 is a view showing the state before and after the movement of the operation pin according to the present invention.
4 is a valve lift diagram to which the present invention is applied.

If described in detail by the accompanying drawings, preferred embodiments of the present invention.

The variable valve lift device of the present invention is configured to include a gas passage 13 formed in the valve head 11, an operating pin 20, and an operating force providing means.

1 and 2, looking at the present invention in detail, the gas passage 13 is formed through the valve head 11 of the intake valve 10a or the valve head 11 of the exhaust valve 10b, The gas passage 13 is formed to enable communication between the combustion chamber and the port. Preferably, it may be applied to the exhaust valve (10b).

Subsequently, the operation pin 20 is provided to be movable in the intake valve 10a or the exhaust valve 10b, and to open or block the gas passage 13 according to the movement operation of the operation pin 20. do.

The actuation force providing means may provide an actuation force for moving the actuation pin 20.

That is, for example, when the operation pin 20 provided in the exhaust valve 10b is moved by the operation force providing means in a state where the exhaust valve 10b is closed, the gas passage 13 blocked by the operation pin 20 ) Is opened to form a state in which the combustion chamber communicates with the exhaust port.

Therefore, during the intake / exhaust administration process of the engine, intake and exhaust operations such as introducing exhaust gas in the exhaust port into the combustion chamber through the gas passage 13 or sending compressed gas into the exhaust port in the combustion chamber are possible, and thus the entire driving area of the vehicle. In this way, the driving efficiency can be optimized.

In addition, with reference to Figure 3 to look at in more detail with respect to the configuration of opening the gas passage 13 by the operation of the operation pin 20, the entire longitudinal direction of the intake valve (10a) or exhaust valve (10b) According to the operation hole 12 is formed hollow so that the lower end of the operation hole 12 is formed to be connected to the bottom surface of the valve head 11, the gas passage 13 is the lower end of the operation hole 12 and the It is formed in a shape penetrating between the upper surfaces of the valve head (11).

In addition, the operation pin 20 is provided in the operation hole 12 so as to be linearly movable.

In particular, one end of the operation pin 20 is provided to block between the lower end of the operation hole 12 and the gas passage 13, but one end of the operation pin 20 according to the linear movement of the operation pin 20 When spaced from the bottom surface of the valve head 11, it is configured to open between the lower end of the operation hole 12 and the gas passage 13.

To this end, a blocking portion 21 having a shape corresponding to the inner diameter of the operating hole 12 is formed at a lower end of the operating pin 20, so that the outer surface of the blocking portion 21 blocks the gas passage 13 Is done.

In addition, when the outer diameter of the working pin 20 formed on the upper end of the blocking portion 21 is formed smaller than the inner diameter of the working hole 12, the blocking portion 21 protrudes toward the lower end of the valve head 11 and is spaced apart. As a gap is formed between the upper end of the blocking part 21 and the lower end of the operation hole 12, the gas passage 13 is opened, and thus the gas in the combustion chamber and the port can flow through the gas passage 13.

On the other hand, the operating force providing means of the present invention to provide an operating force to the operating pin 20 by the oil pressure, it may be configured to include an oil flow path 41, the on-off valve and the controller 80.

For example, an oil passage 41 is formed to provide oil pressure in a moving direction of the operation pin 20, and an opening / closing valve is provided on the oil passage 41 to enable opening and closing operation.

Then, the controller 80 may be provided to control the opening and closing operation of the on-off valve based on the phase angle of the crank. The phase angle of the crank can be measured through a crankshaft position sensor and a camshaft position sensor.

Referring to Figure 1, the configuration of the preferred embodiment of the operating force providing means in detail, the intake valve 10a or the valve bridge 40 is connected to the top of the exhaust valve 10b, the valve bridge 40 ) Inside the oil passage 41 may be formed.

For example, an oil inlet 42 is formed at one end of the oil passage 41 to allow oil to flow in, and an oil outlet 43 is formed at the other end to allow oil to be discharged, and interruption of the oil passage 41 is It is connected to the upper end of the operation hole 12 may be configured to provide an oil pressure to the operation pin 20 provided inside the operation hole 12.

For reference, the valve bridge 40 serves to open and close driving by pressing the intake valve 10a / exhaust valve 10b, and a screw 50 may be provided at the top of the valve bridge 40, The screw 50 and the cam 70 are disposed at both ends of the rocker arm 60, so that the screw 50 is seesawed around the middle of the rocker arm 60 according to the rotation of the cam 70 Thus, the valve bridge 40 is moved together with the screw 50 to open and close the intake / exhaust valve.

At this time, oil for lubrication may be provided in a portion where the lower end of the screw 50 and the valve bridge 40 are in contact, and the oil provided to the lower end of the screw 50 is provided to the oil inlet 42. It can be configured to flow.

In addition, a first opening / closing valve 44 capable of opening / closing operation is installed at the oil inlet 42 side, so as to select whether or not oil is introduced into the oil inlet 42, and opening / closing operation is possible at the oil outlet 43 side. A second opening / closing valve 45 is installed to select whether to discharge the oil discharged to the oil discharge port 43.

Then, the opening and closing operation of the first and second opening and closing valves can be controlled by the controller 80 based on the phase angle of the crank.

That is, when oil flows into the operation hole 12 through the oil passage 41, the operation force to move the operation pin 20 is increased by being able to move the operation pin 20 downward by the oil pressure. You can provide.

Meanwhile, the present invention may further include a return spring 30 that provides elastic restoring force to the working pin 20 moved by the oil pressure.

Looking specifically at the structure in which the return spring 30 is installed through FIG. 3, a fixed support portion 14 is formed in a shape surrounding the operation pin 20 at an internal stop of the operation hole 12, and the operation is performed. The moving support 22 is formed on the upper outer surface of the pin 20.

In addition, between the bottom surface of the movable support portion 22 and the top surface of the fixed support portion 14, both ends of the return spring 30 may be supported to be stretchable.

In addition, the controller 80 of the present invention, when the movement of the operation pin 20 is required to open the gas passage 13, the first opening and closing valve 44 is opened, and the second opening and closing valve 45 ) Can be controlled to supply oil to the inside of the operation hole 12.

That is, when the first opening / closing valve 44 is opened and the second opening / closing valve 45 is closed, the oil flowing into the oil inlet 42 flows along the oil passage 41 to operate the hole 12. The working pin 20 may be moved downward while compressing the return spring 30 by the pressure of the oil flowing into the working hole 12 and flowing into the working hole 12.

On the other hand, when the movement of the operation pin 20 is required to close the gas passage 13, the first opening / closing valve 44 is closed, and the second opening / closing valve 45 is opened to open the oil passage 41. It can be controlled to discharge the oil inside the oil outlet (43).

That is, when the first opening / closing valve 44 is closed, and when the second opening / closing valve 45 is opened, oil in the oil passage 41 is prevented from flowing into the oil inlet 42 and the oil in the oil passage 41 is discharged from the oil outlet ( 43). Accordingly, the oil pressure in the operation hole 12 is reduced, so that the return spring 30 is extended by the elastic restoring force of the return spring 30, so that the operation pin 20 can be restored and moved upward.

On the other hand, by explaining the operation of varying the valve lift on the basis of the structure provided with the operation pin 20 in the exhaust valve 10b by FIGS. 2 and 3, when the piston descends during the intake stroke, the intake valve When the piston reaches a specific phase angle in the state in which 10a is opened and the exhaust valve 10b is closed, the first opening / closing valve 44 is opened and the second opening / closing valve 45 is closed.

Then, the oil flowing through the oil inlet 42 is supplied into the operation hole 12 along the oil passage 41 to form a hydraulic pressure, and the operation provided in the exhaust valve 10b by the generated hydraulic pressure By pushing the pin 20, the working pin 20 is moved downward.

Accordingly, a gap is generated between the operation pin 20 and the bottom surface of the valve head 11, and as the gas passage 13 is opened, the exhaust valve 10b is slightly opened as shown in the valve lift diagram of FIG. 4. It is secured, and the exhaust gas in the exhaust port flows into the combustion chamber through the open gas passage 13, so that the exhaust gas can be heated.

In addition, when the piston rises during the compression stroke during braking (in the case of a fuel cut), when both the intake valve 10a and the exhaust valve 10b are closed, when the piston reaches a certain phase angle, the operating pin ( By supplying oil to 20), the operation pin 20 provided in the exhaust valve 10b is moved downward, thereby ensuring the effect that the exhaust valve 10b is slightly opened while the gas passage 13 is opened.

Accordingly, the compressed gas in the combustion chamber is discharged through the opened gas passage 13 to the exhaust port, so that the engine deceleration force can be increased.

On the other hand, referring to FIG. 1, in the case of an operation situation in which the lowering operation of the operation pin 20 is no longer required, the first opening / closing valve 44 is closed and the second opening / closing valve 45 is opened. do.

Then, the oil does not flow through the oil inlet 42, and the oil filled in the oil passage 41 and the operation hole 12 is discharged through the oil outlet 43, and the elasticity of the return spring 30 The operating pin 20 is moved upward by the restoring force.

Thus, the blocking portion 21 of the lower end of the operating pin 20 is blocked between the gas passage 13 and the operation hole 12, thereby blocking the gas passage 13, thereby enabling general valve lift operation. There will be.

On the other hand, the present invention has been described in detail only with respect to the specific examples described above, but it is apparent to those skilled in the art that various modifications and variations are possible within the technical scope of the present invention, and it is natural that such modifications and modifications belong to the appended claims. .

10a: intake valve
10b: exhaust valve
11: Valve head
12: Working hole
13: gas passage
14: fixed support
20: working pin
21: block
22: moving support
30: return spring
40: valve bridge
41: oil passage
42: oil inlet
43: oil outlet
44: first opening and closing valve
45: second opening and closing valve
50: screw
60: rocker arm
70: cam
80: controller

Claims (8)

A gas passage formed through the valve head of the intake valve or exhaust valve so that the combustion chamber communicates with the port;
An operation pin provided to be movable in the intake valve or the exhaust valve and opening or blocking the gas passage according to the movement operation; And
Variable valve lift device comprising a; operating force providing means for providing an operating force for moving the operating pin. The method according to claim 1,
An operation hole is hollowly formed along the longitudinal direction of the intake valve or exhaust valve so that the lower end of the operation hole connects with the bottom surface of the valve head;
The gas passage is formed between the lower end of the operation hole and the upper surface of the valve head;
The operation pin is provided in the operation hole to be linearly movable;
One end of the working pin is provided to block between the lower end of the working hole and the gas passage, but according to the linear movement of the working pin, one end of the working pin is spaced apart from the bottom surface of the valve head so that the lower end of the working hole and the gas passage are opened. Variable valve lift device, characterized in that configured. The method according to claim 2,
A blocking portion having a shape corresponding to the inner diameter of the working hole is formed at one end of the working pin;
Variable valve lift device characterized in that the outer diameter of the working pin formed on the upper end of the blocking portion is formed smaller than the inner diameter of the working hole. The method according to claim 1,
The operating force providing means,
An oil passage providing oil pressure in a moving direction of the working pin;
An opening / closing valve provided to enable opening / closing operation on the oil passage;
And a controller for controlling opening / closing operation of the opening / closing valve based on the phase angle of the crank. The method according to claim 2,
The operating force providing means,
A valve bridge connected to an upper end of the intake valve or exhaust valve;
The oil passage is formed inside the valve bridge, an oil inlet is formed at one end, an oil outlet is formed at the other end, and a middle end is connected to the upper end of the operation hole to provide oil pressure to the operation pin provided inside the operation hole. ;
A first opening / closing valve installed on the oil inlet side to be opened and closed;
A second opening / closing valve installed on the side of the oil outlet and operated to open and close; And
And a controller configured to control opening and closing operations of the first and second opening and closing valves based on the phase angle of the crank. The method according to claim 5,
And a return spring that provides an elastic restoring force to the operating pin moved by the oil pressure. The method according to claim 6,
A fixed support portion is formed in a shape surrounding the operation pin at an inner middle of the operation hole;
A moving support portion is formed on the upper outer surface of the working pin;
Variable valve lift device, characterized in that a return spring is provided between the movable support and the fixed support. The method according to claim 6,
The controller,
When it is necessary to move the working pin to open the gas passage, the first opening / closing valve is opened and the second opening / closing valve is closed to control oil to be supplied into the operation hole;
A variable valve characterized in that when the movement of the operation pin is required to close the gas passage, the first opening / closing valve is closed and the second opening / closing valve is opened to control the oil inside the oil passage to be discharged to the oil outlet. Lift device.

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