KR101646469B1 - Rotation control apparatus of cvvt - Google Patents

Abstract

A rotation control apparatus of a CVVT is disclosed. The rotation control apparatus of a CVVT comprises a stopper formed to enable one side of an advancement compensation means to be locked to prevent the advancement compensation means from being pressed after the advancement compensation means reaches a set position, wherein the advancement compensation means is installed toward a rotor to enable a rotational force to be continuously applied in the direction of advancing the rotor between the rotor and a stator to enable a lock pin to be locked itself.

Description

[0001] ROTATION CONTROL APPARATUS OF CVVT [0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an advance angle compensation device of an intermediate phase variable valve timing device (CVVT), and more particularly, So that the so-called self-lock operation, which is located at an intermediate position in the chamber, is smoothly implemented.

CVVT is generally applied to vehicles for the purpose of reducing exhaust gas, improving fuel economy and improving output.

In order to facilitate understanding of the present invention, the structure of a conventional CVVT will be described with reference to FIG.

As shown in the figure, the CVVT includes a cam position sensor 11 for detecting the rotation angle of the camshaft and a crank position sensor 12 for detecting the rotation angle of the crankshaft. In addition, the timing belt 14 driven by the crankshaft drives the variable valve timing unit 15, and the variable valve timing unit 15 generally uses a bevel gear.

On the other hand, the ECU 13 receives a signal detected by the cam position sensor 11 and the crank position sensor 12, adjusts the valve timing of the cam according to the crank position, The control signal is transmitted to the oil control valve 16 through which the engine oil is supplied from the engine oil pump 16 to cause the rotation of the cam.

When the oil control valve 16 causes the rotation of the cam in accordance with the control signal of the ECU 13, the cam position sensor 11 detects the position of the camshaft and feeds back to the ECU 13, Calculates a cam rotation amount using the feedback camshaft position information and transmits a signal for controlling the position of the camshaft to the oil control valve 16 based on the calculated amount of cam rotation. This control logic is used to perform unrestricted variable control on the valve timing.

On the other hand, the control logic of the oil control valve 16 according to the crank position and the cam position is mapped to the ECU 13 to smoothly perform the above-described feedback control function. Therefore, when the mapped cam position (target value) and the cam position detected by the cam position sensor 11 are different from each other, the ECU 13 controls the oil control valve 16 to increase or decrease the rotation of the camshaft .

2 is a graph showing the valve opening timing according to the crank angle. The ECU 13 adjusts the valve opening timing in the exhaust stroke and the intake stroke according to the crank angle, and normally, the valve timing of the intake stroke is advanced or retarded.

On the other hand, the CVVT system improves the fuel efficiency by reducing the pumping loss by increasing the valve overlap between intake and exhaust valves, and by optimizing the valve overlap, the effect of re-combustion of unburned gas by internal exhaust gas recirculation (EGR) The effect of reducing the exhaust gas is realized.

As shown in FIG. 3, in recent years, development of a mid-phase CVVT system which recognizes limitations on the responsiveness and limitation of the operating range of the conventional CVVT system has been recognized and developed. In the case of this intermediate phase CVVT, Is controlled at an intermediate position other than the position of the maximum intake angle (intake) and the angle of maximum angle (exhaust), so that the responsiveness is quick and the use area of the cam can be widened, thereby improving fuel economy and reducing exhaust gas.

On the other hand, the lockpin of the intermediate phase CVVT is locked to the lock pinhole located between the advance chamber and the crank chamber in the process of reducing the RPM of the engine, thereby preparing for engine startup at a later time. At this time, the condition that the lock pin is automatically locked to the lock pin hole in the process of reducing the RPM of the engine is called the 'self lock' state.

The self-lock is a function that enables the CVVT to return to the mechanically correct position without any adjustment to maintain the operating safety of the engine at the driving state of the vehicle idle or at the start of the vehicle other than the working area of the CVVT.

However, when the valve timing is not returned to the intermediate phase but comes to the most retarded position, the pressure in the surge tank is raised to the atmospheric pressure level without generating a vacuum in the surge tank when driving the idler of the vehicle. The problem of falling occurs.

Further, when the valve timing does not return to the intermediate phase but comes to the highest angular position, excessive valve timing overlap occurs between the intake valve and the exhaust valve, resulting in a problem that the operation stability of the engine is deteriorated, In some cases, the start-off problem may occur.

In other words, when the rotor 100 and the lock pin are at the most angular position or the most retarded position because the so-called self-lock function of the lock pin is not automatically performed in the intermediate phase CVVT, the breakdown problem and the negative pressure are not properly formed, .

Accordingly, it is necessary to provide a CVVT rotation control device that can adjust the position of the intermediate phase again after the phase change of the lead angle or the crest angle so that the lock pin can be accurately mounted on the lock pin hole, thereby preventing the self lock failure.

Therefore, in order to solve the problem of securing the intermediate phase since the CVVT must overcome the frictional force of the valve system during the advance of the engine during the advance angle operation, it is necessary to separately compensate the rotational force of the advance- The present invention has been made in view of the above problems.

It should be understood that the foregoing description of the background art is merely for the purpose of promoting an understanding of the background of the present invention and is not to be construed as an admission that the prior art is known to those skilled in the art.

KR 10-2004-0100448 A

The present invention has been proposed in order to solve such problems, and it is possible to adjust the position of the lock pin to the lock pin hole by adjusting the position of the intermediate phase again after the phase change of the lead angle or the crank angle, The present invention provides a rotation control device for a CVVT.

In order to achieve the above-mentioned object, the present invention provides a CVVT rotation control device, wherein advance angle compensation means is installed on the rotor side so that a rotational force is constantly applied between the rotor and the stator in a direction to advance the rotor, And a stopper which is formed so that one side of the lead angle compensating means is hooked so that the lead angle compensating means is no longer pressed after reaching the set position.

The lead angle compensating means may be a bias spring.

The lead angle compensation means may be connected to the rotor at one end and to the stator at the other end.

The stopper may be inserted into the rotor where one end of the lead angle compensating means is located.

The rotor may be provided with a pivoting groove for rotating one end of the lead angle compensating means within a predetermined range.

When the rotor is rotated in the advancing direction of the rotor, the advance angle compensating means increases the rotational force of the rotor by the compressive force when the rotor rotates in the advancing direction of the rotor, and when the rotor rotates in the advancing direction, the locking operation of the lock pin is continued through the solenoid valve .

According to the CVVT rotation control apparatus constructed as described above, the load of the lead angle compensating means from the most retarded state to the self lock is made large enough to overcome the cam torque deviation, and when the rotor reaches the self lock position , The stopper does not rotate the lead angle compensating means any more, so that the CVVT is not rotated further in the advancing direction, thereby securing a predetermined accurate intermediate phase, thereby preventing the self-lock failure and ensuring more stable CVVT behavior It will be possible to do.

1 is a general configuration diagram of a CVVT;
2 is a graph showing the valve opening timing between the revolutions of the crankshaft of the CVVT.
3 is a graph showing a valve opening timing according to the rotation angle of the crankshaft of the intermediate phase CVVT.
4 is a view showing a rotation control apparatus of a CVVT according to an embodiment of the present invention.
FIG. 5 is a view showing a lock position in which the lock pin of FIG. 4 is fixed; FIG.
Fig. 6 is a diagram showing the most retarded state of Fig. 4; Fig.

Hereinafter, a CVVT rotation control apparatus according to a preferred embodiment of the present invention will be described with reference to the accompanying drawings.

FIG. 4 is a view showing a rotation control device of a CVVT according to an embodiment of the present invention, FIG. 5 is a view showing a lock position state in which the lock pin 900 of FIG. 4 is fixed, And Fig.

As shown in the figure, the CVVT rotation control apparatus according to the preferred embodiment of the present invention includes a rotor 100 and a stator 300 so that a rotating force is constantly applied to advance the rotor 100 between the rotor 100 and the stator 300 The advance angle compensating means 500 is installed to allow the lock pin 900 to be operated in a self-locking manner, and after one side of the advance angle compensating means 500 is hooked, after the advance angle compensating means 500 reaches the set position And a stopper 700 for preventing further pressurization.

The present invention is characterized in that the advance angle compensation means 500 is installed between the rotor 100 of the CVVT and the stator 300 so that the rotational force is always applied in the direction of advancing the rotor 100, Self-locking operation is implemented.

As shown in FIG. 3, the lead-angle compensating means 500 is in the form of a coil wound with a plurality of windings, and the lead-angle compensating means 500 may in particular be a bias spring. The lead angle compensating means 500 is characterized in that one end is connected to the rotor 100 and the other end is connected to the stator 300 so that an elastic force is applied in an advance angle direction so that the advance angle chamber can be extended at all times. Further, the stopper 700 is inserted into the rotor 100 where one end of the lead angle compensating means 500 is located, and may have a cylindrical shape. The rotor 100 is provided with a rotation groove 110 that allows one end of the advance angle compensating means 500 to rotate within a predetermined range.

The advance angle compensating means 500 is compressed when rotating in the retard direction of the rotor 100 and increases the rotational force of the rotor 100 by the compressive force when the rotor 100 rotates in the advancing direction, The locking operation of the lock pin 900 is continued through the solenoid valve.

In other words, when the rotor 100 rotates in the retard direction, the advance angle compensating means 500 is wound and the elastic force is stored therein. When the rotor 100 rotates in the advancing direction, The rotational force is reinforced. Therefore, there is an advantage that the problem that the rotation in the advancing direction can not be smoothly performed due to the torque of the cam shaft and the frictional force of the valve system can be prevented in advance.

Of course, during rotation in the advancing direction, the rotor 100 is reinforced by the advance angle compensation means 500 to lock the lock pin 900 toward the lock pin hole 910, And the brake is not operated due to the occurrence of negative pressure.

The elastic force stored by the length and diameter of the lead angle compensating means 500 is preferably selected in consideration of the frictional force of the engine valve system and the pressure of the engine oil.

However, when only the advance angle compensating means 500 is applied, there is no problem in securing the intermediate phase theoretically. However, at the time of mass production of the actual vehicle, the engine deviation, the deviation of each component, the deviation of the cam torque and the advance angle compensating means 500 Thus, it is difficult to secure an accurate intermediate phase, thereby causing defects in self-locking. Therefore, the stopper 700 is applied to one side of the advance angle compensation means 500 to prevent further rotation beyond the intermediate phase. The stopper 700 prevents the advance angle compensating means 500 from being further pressurized by the drive torque of the camshaft after the CVVT secures the correct intermediate phase by the advance angle compensating means 500, Thereby preventing the self-lock failure.

The operation of the CVVT rotation control device of the present invention having the above-described structure will be described with reference to FIGS. 5 to 6. FIG.

5 is a view showing a self-lock state in which the lockpin 900 of FIG. 4 is fixed. The rotor 100 and the lock pin 900 are biased in the advancing direction relative to the intermediate phase and then rotated in the retard direction by the drive torque of the cam shaft. When the rotor 100 rotates and reaches the intermediate phase, A self lock in which the lock pin 900 is locked by the lock pin hole 910 is automatically implemented.

On the other hand, Fig. 6 is a diagram showing the most retarded state in Fig. 4, in which the lock pin 900 of the rotor 100 is biased in the retard direction compared with the intermediate phase in the change from the most retarded state to the self lock position And the self-lock is implemented by rotating in the advancing direction. However, even if the same engine speed and oil pressure are supplied to the advance chamber as in the prior art, the rotational force of the rotor 100 is reinforced by the elastic force stored in advance in the advance angle compensating means 500, The lock pin 900 is locked to the lock pin hole 910 by the operation of the solenoid valve, thereby realizing the self lock. At this time, unlike the prior art, the stopper 700 prevents the advance angle compensating means 500 from being continuously pushed over the intermediate phase, so that it is possible to secure an accurate intermediate phase, and the self lock failure is prevented in advance. That is, when the advance angle compensating means 500 comes to the position where the self lock is realized, the advance angle compensating means 500 is no longer pressed by the stopper 700, so that the force that the cam is rotated by the advance angle compensating means 500 Is destroyed.

That is, the load of the lead angle compensating means 500 from the most retarded state to the self lock is increased to such an extent as to overcome the cam torque deviation, and by stopping the advance angle compensating means 500 by the stopper 700, The CVVT is no longer rotated in the advancing direction, and the accurate intermediate phase can be secured, thereby preventing the self-lock from being defective.

Therefore, according to the CVVT rotation control apparatus as described above, the load of the lead angle compensating means from the most retarded state to the self lock is made large enough to overcome the cam torque deviation, and when the rotor reaches the self lock position by the lead angle compensating means , The stopper does not rotate the lead angle compensating means any longer, so that the CVVT is no longer rotated in the advancing direction, thereby ensuring a predetermined accurate intermediate phase, thereby preventing the self-lock failure and ensuring more stable CVVT behavior It will be possible.

While the present invention has been particularly shown and described with reference to specific embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the following claims It will be apparent to those of ordinary skill in the art.

100: Rotor
110: Rotating groove
300:
500: Advance compensation means
700: Stopper
900: Lactin
910: Rock pinhole

Claims (6)

And an advance angle compensating means is provided on the rotor side so that a rotational force is constantly applied in a direction for advancing the rotor so that the self lock operation of the lock pin is realized, And a stopper for stopping the further pressing after reaching the set position,
The rotor is provided with one end of the lead angle compensating means and a stopper inserted therein, and a pivoting groove formed to define the moving region,
The lead angle compensating means is provided such that one end thereof is inserted into the pivotal groove and the other end thereof is fixed to the stator so that one end thereof pressurizes the rotor in the advancing direction,
The stopper is fixed to the stator and inserted into the rotation groove of the rotor,
Wherein the rotor is provided with a lock pin positioned so that one end of the lead angle compensating means is in close contact with the inner wall of the advancing direction side of the pivotal groove and reaches the stopper so as to face the lock pinhole. The method according to claim 1,
And the lead angle compensating means is a bias spring. delete delete delete The method according to claim 1,
The advance angle compensating means increases the rotational force of the rotor by the compressive force when the rotor is rotated in the advancing direction of the rotor,
And the locking operation of the lock pin is continued through the solenoid valve when the rotor is rotated in the advancing direction.

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