KR100574773B1 - A timing control device of a intake and exhaust valves in Variable Valve Timing engine - Google Patents

Abstract

The present invention relates to an intake and exhaust valve timing adjusting device capable of varying the opening and closing time of the intake and exhaust valves by forcibly moving the auto tensioner and the idler gear in a DOHC (Double Over Head Cam) automobile engine. To this end, a rack is connected between the auto tensioner and the idler gear disposed at the lower side of the intake camshaft gear and the exhaust camshaft gear, a linear motion bearing disposed at the bottom of the rack to guide the rack, and a linear motion bearing. Therefore, the connecting means connected to the rack so that the auto-tensioner and the idler gear can be moved horizontally together, the camshaft sensor which is installed in close proximity to the intake camshaft gear to detect the rotation of the intake camshaft gear, and the detection signal that is electrically connected to the camshaft sensor. Is transmitted, and comprises an ECU (60) for controlling the operation of the actuator based on the detection signal. It is characterized by.

DOHC, VVT, Intake, Exhaust, Camshaft, Timing Belt, Actuator, Rack, Pinion, Tensioner

Description

A timing control device of a intake and exhaust valves in Variable Valve Timing engine}

1 is a conceptual diagram illustrating an installation state of an intake and exhaust valve timing adjusting device according to a first embodiment of the present invention;

2 is a conceptual view showing the operation of the intake and exhaust valve timing adjusting device at a low speed according to FIG. 1;

Figure 3 is a block diagram showing whether the operation of the intake and exhaust valve timing adjusting device,

4 is a conceptual diagram illustrating an installation state of an intake and exhaust valve timing adjusting device according to a second embodiment of the present invention;

5 is a conceptual diagram illustrating an operation of an intake and exhaust valve timing adjusting device at a low speed according to FIG. 4.

<Description of the code | symbol about the principal part of drawing>

10: rack, 11: linear moving rod,

20: linear motion bearing, 30: pinion gear,

40: actuator, 50: camshaft sensor,

60: ECU, 100: regulator,

200: timing belt, 300: intake camshaft gear,

400: exhaust camshaft gear, 500: auto tensioner

600: idler gear, 700: water pump,

800: crankshaft gear.

The present invention relates to an intake and exhaust valve timing adjusting device capable of varying the valve opening and closing time of the intake and exhaust valves by forcibly moving the auto tensioner and the idler gear in a DOHC (Double Over Head Cam) vehicle engine.

Most of the current engines have high intake and exhaust valve timings set at high rotation and high power, but the maximum power is high, but the filling efficiency is lowered in the low and medium speed range, which is the most frequently used by the driver, and the engine performance is maximized. There is a disadvantage that is difficult to exert.

The valve timing, especially the variable intake valve timing, is a factor that greatly affects the filling efficiency. If the intake valve is opened early, the valve overlap period becomes longer, and the intake and exhaust inertia flows can be sufficiently used at high speed, resulting in increased volume efficiency. In this case, the volume of gas decreases due to the increase of residual gas, and the emission of HC tends to increase. Therefore, to increase the efficiency of the engine, it is necessary to change the valve opening and closing time at high speed and low speed, respectively.

In addition, the implementation method of the variable valve timing includes an intake camshaft phase shift method for controlling the intake valve opening timing, an exhaust camshaft phase shift method for controlling the exhaust valve opening timing, and an intake and exhaust camshaft for converting both intake and exhaust valves. The phase change method can be largely classified into three types and can be selected.

An engine engine capable of adjusting the intake valve and the exhaust valve timing according to the rotation speed of the engine as described above is a VVT (Variable Valve Timing) engine. Such a VVT engine is an engine which changes the valve opening / closing timing of an intake valve and an exhaust valve according to low speed and high speed. However, unlike the conventional engine, such a VVT engine is different from the shape of the cylinder head or the shape of the camshaft and is produced by a specialized manufacturing production line, and thus cannot be applied to the existing production facility line. Therefore, the present invention aims to develop an add-on type valve timing control device which can be easily applied to the production production line of an existing DOHC engine as well as the VVT effect of a new engine in a new way. have.

Accordingly, the present invention has been made in view of the above-mentioned conventional problems, and a first object of the present invention is to induce an intake and idle force by forcibly moving an auto tensioner and an idler gear in an automobile engine having a double over head cam (DOHC) structure. It is to provide an intake and exhaust valve timing adjusting device capable of varying the valve opening and closing timing of the exhaust valve.

The second object of the present invention is to adjust the timing of opening and closing the valves of the intake and exhaust valves by changing the initial rotation angles of the intake and exhaust camshaft gears which are interlocked with the rotation of the timing belt which moves together with the auto tensioner and idler gear. It is to provide an intake and exhaust valve timing adjuster that can be variable.

In addition, it is a third object of the present invention to provide an intake and exhaust valve timing adjusting device that can be easily applied to a production line of an existing DOHC engine.

These objects of the present invention, in the DOHC timing belt drive structure,

A rack connected between the auto tensioner and the idler gear so that the auto tensioner and the idler gear can be connected to each other, and the linear motion disposed at the bottom of the rack to guide the rack. Bearings, connecting means connected to the rack so that the auto-tensioner and idler gears can be moved horizontally along the linear motion bearings, a camshaft sensor installed close to the intake camshaft gear to detect rotation of the intake camshaft gear, and a camshaft sensor It is achieved by the intake and exhaust valve timing adjustment device, characterized in that it comprises an ECU that is electrically connected to the sensing signal is transmitted, the ECU to control the operation of the actuator based on the sensing signal.

In the above, the connecting means is preferably a pinion gear connected to the actuator and engaged with the upper part of the rack.

In the above, the connecting means is preferably a linear moving rod connected to the lower part of the rack, and a pinion gear connected to the actuator and disposed at the lower part of the rack and connected to the linear moving rod.

The camshaft sensor is preferably installed in close proximity to the exhaust camshaft gear to detect the rotation of the exhaust camshaft gear.

Other objects, specific advantages and novel features of the present invention will become more apparent from the following detailed description and preferred embodiments in conjunction with the accompanying drawings.

Hereinafter, the intake and exhaust valve timing adjusting apparatus according to the present invention will be described in detail together with the accompanying drawings.

1 is a conceptual diagram showing an installation state of the intake and exhaust valve timing adjusting apparatus according to the first embodiment of the present invention. As shown in FIG. 1, the present invention provides an automatic opening and closing of the intake and exhaust valves by forcibly moving the auto tensioner 500 and the idler gear 600 in an automobile engine having a double over head cam (DOHC) structure. It relates to an intake and exhaust valve timing adjusting device (100) that can be variable.

That is, the present invention is a device that can improve the efficiency of the engine by minimizing the valve overlap at low rotation and low power because the intake and exhaust valve timing of the existing DOHC engine is set around high rotation, high output.

The timing belt 200 is connected to the intake camshaft gear 300 and the exhaust camshaft gear 400. In addition, the crankshaft gear 800 for receiving the driving force, the auto tensioner 500 for adjusting the tension of the timing belt 200, the idler gear 600 for guiding the timing belt 200, water pump 700 and the like are connected and configured.

The adjusting device 100 according to the present invention includes a rack 10 connected between the timing belt 200 and the auto tensioner 500 and the idler gear 600 connected to each of the gears 300, 400, 500, 600, 700, and 800. In order to guide the rack 10, the linear motion bearing 20 disposed below and fixed to the bottom of the rack 10, and the auto tensioner 500 and the idler gear 600 along the linear motion bearing 20 accompany it. It comprises a connecting means provided in the rack 10 and an actuator 40 connected to the connecting means to be horizontally moved.

In addition, a camshaft sensor 50 is proximately installed on any one of the camshaft gears 300 and 400 selected to detect rotation (or rotational speed, rotational speed) of the intake camshaft gear 300 or the exhaust camshaft gear 400. The camshaft sensor 50 has a structure in which an ECU 60 for controlling the operation of the actuator 40 is electrically connected.

Here, the rack 10 is connected between the auto-tensioner 500 and the idler gear 600, the horizontal movement by the connecting means to rotate the timing belt 200, according to the intake and exhaust cam shaft gear (300,400) It is provided to change the initial rotation angle. That is, as the timing belt 200 is forcibly rotated, the intake and exhaust camshaft gears 300 and 400 are rotated by a predetermined angle, thereby providing a structure capable of simultaneously varying the valve opening / closing timing of the intake and exhaust valves.

The connecting means is a pinion gear 30 which is connected to the actuator 40 and meshes with and engaged with the upper portion of the rack 10. When the pinion gear 30 is rotated (counterclockwise) by the actuator 40, the rack 10 is slid from the top of the linear motion bearing 20 to the right to thereby move the auto tensioner 500. And idler gear 600 also has a structure that is interlocked with each other to move to the right.

Therefore, when the pinion gear 30 is rotated by the operation of the actuator 40, the rack 10 may be slid in the linear motion bearing 20 to be moved to the right side. However, the increased length of the section timing belt 200 between the intake camshaft gear 300 and the exhaust camshaft gear 400 is reduced to the length of the section timing belt 200 between the intake camshaft gear 300 and the water pump 600. same.

2 is a conceptual diagram showing the operation of the intake and exhaust valve timing adjusting device at a low speed according to FIG. 1, and FIG. 3 is a block diagram showing the operation of the intake and exhaust valve timing adjusting device. As shown in Figures 2 and 3, the camshaft sensor 50 of the present invention is to rotate the intake camshaft gear 300 or the exhaust camshaft gear 400 to minimize the inefficient valve overlap of the engine at low speeds. It works by sensing.

The actuator 40 connected to the pinion gear 30 is for providing a driving force. In this case, the movement of the rack 10 depends on the rotational speed RPM of the intake camshaft gear 300 or the exhaust camshaft gear 400. Since it is determined, the camshaft sensor 50 is provided at any one selected to detect the rotational speed RPM of the intake camshaft gear 300 or the exhaust camshaft gear 400.

The camshaft sensor 50 is electrically connected to the ECU 60 for regulating the operation of the actuator 40. Accordingly, the detection signal of the camshaft sensor 50 is transmitted to the ECU 60, and the ECU 60 adjusts the operation of the actuator 40 based on the detection signal, and as a result, the movement of the rack 10 is performed by the intake camshaft. It is based on the rotation speed of the gear 300 or the exhaust camshaft gear 400.

The operation of the present invention according to this structure is as follows. First, the camshaft sensor 50 detects the rotation of the intake camshaft gear 300 or the exhaust camshaft gear 400. The detection signal of the camshaft sensor 50 is provided to the ECU 60, and the ECU 60 calculates the rotation speed or the rotational speed of the intake camshaft gear 300 or the exhaust camshaft gear 400 based on the detection signal. do. Therefore, it may be determined whether high speed driving or low speed driving is required. According to the requirement of the traveling speed, the ECU 60 adjusts the operation of the actuator 40.

If the low-speed driving, the actuator 40 is operated so that the initial rotation angle of the intake camshaft gear 300 and the exhaust camshaft gear 400 can be converted. At this time, the actuator 40 is attached to the pinion gear 30 can be rotated together and can be operated using the oil pressure and solenoid valve and the cylinder of the motor and the reducer or power steering oil pump. Then, the rack 10 is moved to the right in accordance with the rotation (counterclockwise) of the pinion gear 30 to push the auto-tensioner 500 and the idler gear 600 at the same time.

Then, the timing belt 200 is also rotated counterclockwise by the right moving length of the rack 10 (= by the increased length of the shift), and thus the intake camshaft gear 300 and the exhaust camshaft gear 400 are respectively circumferential. It rotates a predetermined angle in the counterclockwise direction (rotation direction of the timing belt) to two points, namely, arcs of the intake and exhaust camshaft gears 400.

Accordingly, the intake and exhaust camshaft gears 300 and 400 simultaneously change the position of the initial rotation angle, thereby reducing the overlap of the intake and exhaust valves, thereby reducing the rotational speed, thereby increasing fuel efficiency and idle stability (reducing vibration) at low speeds. You can.

If driving at high speed, the ECU 60 operates the actuator 40 in reverse so that the initial rotation angle of the exhaust camshaft gear 400 can be returned to its original state. As the pinion gear 30 is rotated (clockwise), the rack 10 is moved to the left so that the intake and exhaust camshaft gears 300 and 400 are returned to their initial rotation angles.

4 is a conceptual diagram showing an installation state of the intake and exhaust valve timing adjusting apparatus according to the second embodiment of the present invention, Figure 5 is a conceptual diagram showing the operation of the intake and exhaust valve timing adjusting apparatus at a low speed according to FIG. to be. As shown in Figures 4 and 5, the connecting means is a linear movement rod 11 connected to the lower portion of the rack 10, the actuator 40 is connected to the lower portion of the rack 10 and the linear movement rod It consists of the pinion gear 30 linked with 11.

This structure is the pinion gear 30 is arranged at a predetermined interval with respect to the linear movement rod 11, the linear movement rod 11 is a structure that is slidingly coupled to the upper portion of the linear motion bearing (20). In this case, the pinion gear 30 and the linear movement rod 11 are linked to each other so that the linear movement rod 11 can be moved according to the rotation of the pinion gear 30. Therefore, when the pinion gear 30 rotates (clockwise) by the actuator 40, the linear movement rod 11 moves to the right by the linear motion bearing 20. Therefore, it is possible to express the same operating effect as in the first embodiment mentioned above. In the low speed and high speed operation, the actuator 40 may be controlled. That is, the home position of the actuator 40 can also be reversed. And this control is made continuously.

As described above, according to the exhaust valve timing adjusting device 100, the overlapping phenomenon of the valve may be minimized by varying initial rotation angles of the intake and exhaust valves at low rotation and low output, but according to the structure of the engine By varying the initial rotation angle of the exhaust valve can be configured so that a lot of overlap occurs.

As described above, the intake and exhaust valve timing adjusting device according to the present invention is applicable to a new engine, can be easily applied to the production line of the existing DOHC engine, and the effect of the significant performance improvement and fuel economy of the existing engine applied There is a feature that can bring.

In addition, due to the increase in the amount of residual gas at low speed in the existing engine, the volume efficiency is reduced and HC emissions are prevented from increasing, thereby contributing to environmental pollution.

Although the present invention has been described in connection with the above-mentioned preferred embodiments, it is possible to make various modifications or variations without departing from the spirit and scope of the invention. Accordingly, the appended claims will cover such modifications and variations as fall within the spirit of the invention.

Claims (4)

In the DOHC timing belt drive structure, Between the auto tensioner 500 and the idler gear 600 such that the auto tensioner 500 and the idler gear 600 disposed below the intake camshaft gear 300 and the exhaust camshaft gear 400 can be interconnected. A rack 10 connected to the rack; A linear motion bearing 20 disposed below and fixed to the rack 10 to guide the rack 10; Connecting means provided in the rack 10 such that the auto-tensioner 500 and the idler gear 600 are horizontally moved along the linear motion bearing 20; A camshaft sensor 50 installed close to the intake camshaft gear 300 to detect rotation of the intake camshaft gear 300; And And an ECU 60 electrically connected to the camshaft sensor 50 to transmit a detection signal, and controlling an operation of the actuator 40 on the basis of the detection signal. Timing adjuster. The method of claim 1, The connecting means is connected to the actuator (40), the intake and exhaust valve timing adjustment device, characterized in that the pinion gear (30) engaged with the upper portion of the rack (10). The method of claim 1, The connecting means is a linear movement rod 11 is connected to the lower portion of the rack 10, the actuator 40 is connected to the lower portion of the rack 10 and the linear movement rod 11 is connected to the link Intake and exhaust valve timing adjustment device, characterized in that the pinion gear (30). The method of claim 1, The camshaft sensor 50 is installed in close proximity to the exhaust camshaft gear 400 to detect the rotation of the exhaust camshaft gear 400, intake and exhaust valve timing adjustment device.

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